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  • 1.
    Aardal, Elisabeth
    et al.
    Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Ann-Charlotté, Holm
    Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Cortisol in Saliva: Reference Ranges and Relation to Cortisol in Serum1995In: European Journal of Clinical Chemistry and Clinical Biochemistry, ISSN 0939-4974, Vol. 33, p. 927-932Article in journal (Refereed)
    Abstract [en]

    The aim of this study was to establish morning and evening reference ranges for cortisol in saliva. Another objective was to compare the concentrations of the mainly free cortisol in saliva to those of total cortisol in serum as determined with a commercial radioimmunoassay. The concentrations were determined in matched samples of saliva and serum collected at 8am and 10pm from 197 healthy volunteers. The saliva samples were stable for at least 7 days at room temperature and for 9 months at —20 °C. Reference ranges, the central 95%, were estimated to 3.5—27.0 nmol/1 at 8 am and < 6.0 nmol/1 at 10 pm. The intra-assay coefficient of variation (CV) was below 5% and total CV below 10%. The relation between the cortisol concentrations in serum and saliva was nonlinear with r = 0.86 for serum concentrations < 450 nmol/1 and r = 0.44 for serum concentrations ^ 450 nmol/1. In conclusion, the satisfactory precision of the analysis and the simple non-invasive sampling procedure suggest that saliva may be used for cortisol measurements in situations where blood sampling is difficult to perform.

  • 2.
    Aardal-Eriksson, Elisabeth
    Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Linköping University, Department of Neuroscience and Locomotion, Psychiatry. Linköping University, Faculty of Health Sciences.
    Salivary cortisol and posttraumatic stress reactions: methodological and applied studies before and after trauma2002Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The field of psychotraumatology has its roots in ancient history. During the past decades, the surveillance of the psychobiological background of reactions to and consequences of traumatic stress has made great progress and the complexity of the human stress response system stands out. The hypothalamic-pituitary-adrenocortical axis activity, modulated by various neuroimmunological substances, seems to play a major role in the stress response. However, there are still inconsistencies in explanations of relationships between biological and psychological changes following traumatic stress. Moreover, the matter of predictive factors for the development of posttraumatic morbidity is still in a speculative phase.

    The aims of the present thesis were to further develop a commercial serum cortisol radioimmunoassay (RIA) for determination of cortisol in saliva and to test its reliability, specificity and sensitivity as a biochemical assay. The saliva sampling procedures and sample storage stability were also to be tested. Further issues were to investigate determinations of salivary cortisol and serum prolactin in relation to selfratings of posttraumatic psychological distress and general psychological health. Possible predictive and concurrent validity of salivary cortisol as a biochemical marker for posttraumatic psychological distress were to be tested.

    Cortisol is present in saliva mainly in non-protein form, representing the free, biologically active fraction of the total plasma cortisol concentration. In a first phase of the present thesis, the commercial serum cortisol RIA was modified for determination of cortisol in saliva. The relation between salivary and serum cortisol concentrations was tested. Reference ranges at 8 AM and 10 PM for the salivary cortisol assay were established from 195 healthy subjects. Salivary cortisol concentrations were tested in relation to serum cortisol in estimating adrenocortical function during endocrine dynamic function tests in 37 patients and 13 healthy controls. In testing salivary cortisol as a marker for stress for fieldwork use, a screening study was performed on 66 male rescue workers. Salivary cortisol at 8 AM and 10 PM and serum prolactin were determined and general psychological health and posttraumatic psychological distress were estimated with the self-rating scales General Health Questionnaire, Impact of Event Scale and Posttraumatic Symptom Scale. These scales were used in the second phase of the thesis. Three applied follow-up studies were performed with sampling of salivary cortisol and self-ratings: (a) a study of 31 UN-soldiers five days, two and nine months after a mine accident; (b) a study of 145 UN-soldiers before, at return, and two and six month after a six month mission. (c) a study of 101 UN-soldiers six and twelve months after a six month mission with severe combat exposure.

    The results from the present thesis indicate that the modified method of salivary cortisol determination possesses sufficient precision, accuracy, sample storage stability and procedural advantages for laboratory, clinical and field application. Moreover, it possesses moderate predictive information and moderate to high concurrent validity as a biochemical marker for posttraumatic psychological distress.

    List of papers
    1. Cortisol in Saliva: Reference Ranges and Relation to Cortisol in Serum
    Open this publication in new window or tab >>Cortisol in Saliva: Reference Ranges and Relation to Cortisol in Serum
    1995 (English)In: European Journal of Clinical Chemistry and Clinical Biochemistry, ISSN 0939-4974, Vol. 33, p. 927-932Article in journal (Refereed) Published
    Abstract [en]

    The aim of this study was to establish morning and evening reference ranges for cortisol in saliva. Another objective was to compare the concentrations of the mainly free cortisol in saliva to those of total cortisol in serum as determined with a commercial radioimmunoassay. The concentrations were determined in matched samples of saliva and serum collected at 8am and 10pm from 197 healthy volunteers. The saliva samples were stable for at least 7 days at room temperature and for 9 months at —20 °C. Reference ranges, the central 95%, were estimated to 3.5—27.0 nmol/1 at 8 am and < 6.0 nmol/1 at 10 pm. The intra-assay coefficient of variation (CV) was below 5% and total CV below 10%. The relation between the cortisol concentrations in serum and saliva was nonlinear with r = 0.86 for serum concentrations < 450 nmol/1 and r = 0.44 for serum concentrations ^ 450 nmol/1. In conclusion, the satisfactory precision of the analysis and the simple non-invasive sampling procedure suggest that saliva may be used for cortisol measurements in situations where blood sampling is difficult to perform.

    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-80129 (URN)10.1515/cclm.1995.33.12.927 (DOI)
    Available from: 2012-08-21 Created: 2012-08-21 Last updated: 2012-08-21Bibliographically approved
    2. Salivary cortisol: an alternative to serum cortisol determinations in dynamic function tests
    Open this publication in new window or tab >>Salivary cortisol: an alternative to serum cortisol determinations in dynamic function tests
    1998 (English)In: Clinical Chemistry and Laboratory Medicine, ISSN 1434-6621, E-ISSN 1437-4331, Vol. 36, no 4, p. 215-222Article in journal (Refereed) Published
    Abstract [en]

    Salivary cortisol was measured as an alternative to serum cortisol as a marker for adrenocortical function following insulin tolerance test, corticotropin-releasing-hormone stimulation and adreno-corticotrophic hormone stimulation. During insulin tolerance test and corticotropin-releasing-hormone stimulation adreno-corticotrophic hormone was also measured. The tests were performed on healthy control subjects as well as on patients under investigation for various disturbances in the hypothalamic-pituitary-adrenocortical axis (insulin tolerance test: 3 controls on two occasions and 14 patients; corticotropin-releasing-hormone stimulation: 4 controls and 18 patients; adreno-corticotrophic hormone stimulation: 6 controls and 10 patients). Five patients underwent both insulin tolerance test and corticotropin-releasing-hormone stimulation. Using criteria for adequate cortisol response in serum, the patients were classified as good or poor responders. In 42 of the 45 tests performed the same conclusion as to cortisol status was drawn when based on serum and salivary cortisol responses. In healthy subjects and good responders the mean cortisol relative increase was greater in saliva than in serum in all three tests (p < 0.05). Characteristic of the results for the insulin tolerance test was a significant initial mean decrease (p < 0.05), not found in serum, and the highest observed salivary cortisol value was delayed for at least 30 minutes compared to that in serum. Plasma adreno-corticotrophic hormone correlated significantly with the cortisol concentrations determined 15 minutes later in serum (r = 0.54–0.64) and in saliva (r = 0.76–0.85). The more pronounced cortisol response in saliva than in serum and its closer correlation with adreno-corticotrophic hormone offer advantages over serum cortisol, suggesting salivary cortisol measurement may be used as an alternative parameter in dynamic endocrine tets.

    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-80133 (URN)10.1515/CCLM.1998.037 (DOI)
    Available from: 2012-08-21 Created: 2012-08-21 Last updated: 2017-12-07Bibliographically approved
    3. Salivary cortisol and serum prolactin in relation to stress rating scales in a group of rescue workers
    Open this publication in new window or tab >>Salivary cortisol and serum prolactin in relation to stress rating scales in a group of rescue workers
    1999 (English)In: Biological Psychiatry, ISSN 0006-3223, E-ISSN 1873-2402, Vol. 46, no 6, p. 850-855Article in journal (Refereed) Published
    Abstract [en]

    Background: Rescue service personnel are often exposed to traumatic events as part of their occupation, and higher prevalence rates of psychiatric illness have been found among this group.

    Methods: In 65 rescue workers, salivary cortisol at 8 am and 10 pm and serum prolactin at 8 am were related to the psychiatric self-rating scale General Health Questionnaire (GHQ-28) measuring psychiatric health, and the Impact of Events Scale (IES) and Post Traumatic Symptom Scale (PTSS) measuring posttraumatic symptoms.

    Results: Seventeen percent of the study population scored above the GHQ-28 cut-off limit but none scored beyond the cut-off limit in the IES and PTSS questionnaires. Salivary cortisol concentration at 10 pm correlated with statistical significance to anxiety (p < .005) and depressive symptoms (p < .01) measured with GHQ-28, as well as to posttraumatic symptoms, with avoidance behavior measured with IES (p < .01) and PTSS (p < .005). Two of the rescue workers were followed over time with the same sampling procedure after a major rescue commission.

    Conclusions: The correlation between evening salivary cortisol and anxiety, depressiveness, and posttraumatic avoidance symptoms indicates that these parameters can be used in screening and follow-up after traumatic stress events.

    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-24816 (URN)10.1016/S0006-3223(98)00381-3 (DOI)9214 (Local ID)9214 (Archive number)9214 (OAI)
    Available from: 2009-10-07 Created: 2009-10-07 Last updated: 2017-12-13Bibliographically approved
    4. Salivary cortisol, posttraumatic stress symptoms, and general health in the acute phase and during 9-month follow-up
    Open this publication in new window or tab >>Salivary cortisol, posttraumatic stress symptoms, and general health in the acute phase and during 9-month follow-up
    2001 (English)In: Biological Psychiatry, ISSN 0006-3223, E-ISSN 1873-2402, Vol. 50, no 12, p. 986-993Article in journal (Refereed) Published
    Abstract [en]

    Background: Because traumatic events are unpredictable, there are few studies of psychobiological states immediately following such events. Our study aimed to determine the relation of salivary cortisol to psychologic distress immediately after a traumatic event and then during follow-up.

    Methods: Measurement of morning and evening salivary cortisol and ratings of psychologic distress (using the Impact of Events Scale [IES], the Post Traumatic Symptom Scale, and the General Health Questionnaire) were performed with 31 United Nations soldiers at three time points—5 days and 2 and 9 months—following a mine accident in Lebanon.

    Results: Five days after the accident, 15 subjects reported substantial posttraumatic distress according to the IES, as well as significantly lower morning and higher evening cortisol levels compared with the low-impact group. Within 9 months, the posttraumatic distress of the high-impact group was reduced, accompanied by an increase in morning and a decrease in evening cortisol levels. There were significant relationships between evening cortisol and all rating scales at the first and third time points.

    Conclusions: Subclinical posttraumatic stress following an adverse event can be measured biologically via salivary cortisol levels soon after the event.

    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-24817 (URN)10.1016/S0006-3223(01)01253-7 (DOI)9215 (Local ID)9215 (Archive number)9215 (OAI)
    Available from: 2009-10-07 Created: 2009-10-07 Last updated: 2017-12-13Bibliographically approved
    5. Pre-trauma Salivary Cortisol Levels and General Health Ratings in Relation to Post-trauma Changes in Cortisol and Psychological Distress after UN-service in Bosnia
    Open this publication in new window or tab >>Pre-trauma Salivary Cortisol Levels and General Health Ratings in Relation to Post-trauma Changes in Cortisol and Psychological Distress after UN-service in Bosnia
    (English)Manuscript (preprint) (Other academic)
    Abstract [en]

    Background: The psychobiology of post-traumatic distress is known to some extent, however the pre-trauma psychobiology is not. The aims of the present study were to relate pre- and post-trauma salivary cortisol levels and general health to post-traumatic distress in a Swedish UN-battalion in Bosnia.

    Methods: Salivary 8 AM and I 0 PM cortisol levels and "General Health Questionnaire" ratings were collected from 145 subjects before the six months' mission, at return and two and six months after mission. During follow-up, the ratings were extended by the "Impact of Events Scale" (IES) and "Post Traumatic Symptom Scale".

    Results: Low pre-trauma morning and evening salivary cortisol levels were statistically significantly related to high scores in all rating scales six months after mission and to increasing IES scores during follow-up. Low morning and high evening post-trauma salivary cortisol levels were related to high ratings of psychological distress six months after mission

    Conclusions: Pre-trauma salivary cortisol levels seem to be related to posttrauma psychological distress, however not to the extent that salivary cortisol levels in a simple way could be used for predictive screening.

    Keywords
    Saliva, cortisol, relation to, rating scales, traumatic stress, UN-soldiers
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-80134 (URN)
    Available from: 2012-08-21 Created: 2012-08-21 Last updated: 2012-08-21Bibliographically approved
    6. Twelve Months Follow-up of Salivary Cortisol in Relation to Psychological Distress and General Health in Swedish UN-personnel after Severe Combat Exposure during Six Months Mission in Bosnia
    Open this publication in new window or tab >>Twelve Months Follow-up of Salivary Cortisol in Relation to Psychological Distress and General Health in Swedish UN-personnel after Severe Combat Exposure during Six Months Mission in Bosnia
    (English)Manuscript (preprint) (Other academic)
    Abstract [en]

    Background: Our group has presented evidence of relationships between salivary cortisol levels and psychological distress before, during and after trauma-related stress. The aim of the present study was to confirm the part of evidence of relationships between salivary cortisol and posttraumatic distress and their change over time.

    Methods: Salivary cortisol levels at 8 AM and 10 PM and self-ratings were collected from 106 subjects six and twelve months after a six months UNmission in Bosnia. The rating instruments were the "Impact of Event Scale" (IES), the "Post Traumatic Symptom Scale" and the "General Health Questionnaire".

    Results: Significant statistical interactions were found between changes in mean cortisol levels and IES scores over time. Decreasing evening cortisol levels over time were significantly related to decreasing IES scores and vice versa. Morning cortisol levels showed negative, and evening cortisol positive correlations with all rating scores.

    Conclusions: The evidence from previous studies on trauma related stress, that salivary cortisol is related to the development of posttraumatic stress reactions, the morning cortisol in reverse (negative) direction to that (positive) of evening cortisol, were confirmed.

    Keywords
    Saliva, cortisol, follow-up, relation to, rating scales, traumatic stress, UN-soldiers
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-80136 (URN)
    Available from: 2012-08-21 Created: 2012-08-21 Last updated: 2012-08-21Bibliographically approved
  • 3.
    Aardal-Eriksson, Elisabeth
    et al.
    Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Eriksson, Thomas E.
    Linköping University, Department of Neuroscience and Locomotion, Psychiatry. Linköping University, Faculty of Health Sciences.
    Thorell, Lars-Håkan
    Linköping University, Department of Neuroscience and Locomotion, Psychiatry. Linköping University, Faculty of Health Sciences.
    Pre-trauma Salivary Cortisol Levels and General Health Ratings in Relation to Post-trauma Changes in Cortisol and Psychological Distress after UN-service in BosniaManuscript (preprint) (Other academic)
    Abstract [en]

    Background: The psychobiology of post-traumatic distress is known to some extent, however the pre-trauma psychobiology is not. The aims of the present study were to relate pre- and post-trauma salivary cortisol levels and general health to post-traumatic distress in a Swedish UN-battalion in Bosnia.

    Methods: Salivary 8 AM and I 0 PM cortisol levels and "General Health Questionnaire" ratings were collected from 145 subjects before the six months' mission, at return and two and six months after mission. During follow-up, the ratings were extended by the "Impact of Events Scale" (IES) and "Post Traumatic Symptom Scale".

    Results: Low pre-trauma morning and evening salivary cortisol levels were statistically significantly related to high scores in all rating scales six months after mission and to increasing IES scores during follow-up. Low morning and high evening post-trauma salivary cortisol levels were related to high ratings of psychological distress six months after mission

    Conclusions: Pre-trauma salivary cortisol levels seem to be related to posttrauma psychological distress, however not to the extent that salivary cortisol levels in a simple way could be used for predictive screening.

  • 4.
    Aardal-Eriksson, Elisabeth
    et al.
    Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Eriksson, Thomas E.
    Linköping University, Department of Neuroscience and Locomotion, Psychiatry. Linköping University, Faculty of Health Sciences.
    Thorell, Lars-Håkan
    Linköping University, Department of Neuroscience and Locomotion, Psychiatry. Linköping University, Faculty of Health Sciences.
    Salivary cortisol, posttraumatic stress symptoms, and general health in the acute phase and during 9-month follow-up2001In: Biological Psychiatry, ISSN 0006-3223, E-ISSN 1873-2402, Vol. 50, no 12, p. 986-993Article in journal (Refereed)
    Abstract [en]

    Background: Because traumatic events are unpredictable, there are few studies of psychobiological states immediately following such events. Our study aimed to determine the relation of salivary cortisol to psychologic distress immediately after a traumatic event and then during follow-up.

    Methods: Measurement of morning and evening salivary cortisol and ratings of psychologic distress (using the Impact of Events Scale [IES], the Post Traumatic Symptom Scale, and the General Health Questionnaire) were performed with 31 United Nations soldiers at three time points—5 days and 2 and 9 months—following a mine accident in Lebanon.

    Results: Five days after the accident, 15 subjects reported substantial posttraumatic distress according to the IES, as well as significantly lower morning and higher evening cortisol levels compared with the low-impact group. Within 9 months, the posttraumatic distress of the high-impact group was reduced, accompanied by an increase in morning and a decrease in evening cortisol levels. There were significant relationships between evening cortisol and all rating scales at the first and third time points.

    Conclusions: Subclinical posttraumatic stress following an adverse event can be measured biologically via salivary cortisol levels soon after the event.

  • 5.
    Aardal-Eriksson, Elisabeth
    et al.
    Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Eriksson, Thomas E.
    Linköping University, Department of Neuroscience and Locomotion, Psychiatry. Linköping University, Faculty of Health Sciences.
    Thorell, Lars-Håkan
    Linköping University, Department of Neuroscience and Locomotion, Psychiatry. Linköping University, Faculty of Health Sciences.
    Twelve Months Follow-up of Salivary Cortisol in Relation to Psychological Distress and General Health in Swedish UN-personnel after Severe Combat Exposure during Six Months Mission in BosniaManuscript (preprint) (Other academic)
    Abstract [en]

    Background: Our group has presented evidence of relationships between salivary cortisol levels and psychological distress before, during and after trauma-related stress. The aim of the present study was to confirm the part of evidence of relationships between salivary cortisol and posttraumatic distress and their change over time.

    Methods: Salivary cortisol levels at 8 AM and 10 PM and self-ratings were collected from 106 subjects six and twelve months after a six months UNmission in Bosnia. The rating instruments were the "Impact of Event Scale" (IES), the "Post Traumatic Symptom Scale" and the "General Health Questionnaire".

    Results: Significant statistical interactions were found between changes in mean cortisol levels and IES scores over time. Decreasing evening cortisol levels over time were significantly related to decreasing IES scores and vice versa. Morning cortisol levels showed negative, and evening cortisol positive correlations with all rating scores.

    Conclusions: The evidence from previous studies on trauma related stress, that salivary cortisol is related to the development of posttraumatic stress reactions, the morning cortisol in reverse (negative) direction to that (positive) of evening cortisol, were confirmed.

  • 6.
    Aardal-Eriksson, Elisabeth
    et al.
    Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Eriksson, Thomas
    Linköping University, Department of Neuroscience and Locomotion, Psychiatry. Linköping University, Faculty of Health Sciences.
    Holm, Ann-Charlotte
    Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Lundin, Tom
    Department of Psychiatry, Uppsala Academic Hospital, Uppsala University, Uppsala (TL), Sweden.
    Salivary cortisol and serum prolactin in relation to stress rating scales in a group of rescue workers1999In: Biological Psychiatry, ISSN 0006-3223, E-ISSN 1873-2402, Vol. 46, no 6, p. 850-855Article in journal (Refereed)
    Abstract [en]

    Background: Rescue service personnel are often exposed to traumatic events as part of their occupation, and higher prevalence rates of psychiatric illness have been found among this group.

    Methods: In 65 rescue workers, salivary cortisol at 8 am and 10 pm and serum prolactin at 8 am were related to the psychiatric self-rating scale General Health Questionnaire (GHQ-28) measuring psychiatric health, and the Impact of Events Scale (IES) and Post Traumatic Symptom Scale (PTSS) measuring posttraumatic symptoms.

    Results: Seventeen percent of the study population scored above the GHQ-28 cut-off limit but none scored beyond the cut-off limit in the IES and PTSS questionnaires. Salivary cortisol concentration at 10 pm correlated with statistical significance to anxiety (p < .005) and depressive symptoms (p < .01) measured with GHQ-28, as well as to posttraumatic symptoms, with avoidance behavior measured with IES (p < .01) and PTSS (p < .005). Two of the rescue workers were followed over time with the same sampling procedure after a major rescue commission.

    Conclusions: The correlation between evening salivary cortisol and anxiety, depressiveness, and posttraumatic avoidance symptoms indicates that these parameters can be used in screening and follow-up after traumatic stress events.

  • 7.
    Aardal-Eriksson, Elisabeth
    et al.
    Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Karlberg, Bengt E.
    Linköping University, Department of Medicine and Care, Internal Medicine. Linköping University, Faculty of Health Sciences.
    Holm, Ann-Charlotte
    Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Salivary cortisol: an alternative to serum cortisol determinations in dynamic function tests1998In: Clinical Chemistry and Laboratory Medicine, ISSN 1434-6621, E-ISSN 1437-4331, Vol. 36, no 4, p. 215-222Article in journal (Refereed)
    Abstract [en]

    Salivary cortisol was measured as an alternative to serum cortisol as a marker for adrenocortical function following insulin tolerance test, corticotropin-releasing-hormone stimulation and adreno-corticotrophic hormone stimulation. During insulin tolerance test and corticotropin-releasing-hormone stimulation adreno-corticotrophic hormone was also measured. The tests were performed on healthy control subjects as well as on patients under investigation for various disturbances in the hypothalamic-pituitary-adrenocortical axis (insulin tolerance test: 3 controls on two occasions and 14 patients; corticotropin-releasing-hormone stimulation: 4 controls and 18 patients; adreno-corticotrophic hormone stimulation: 6 controls and 10 patients). Five patients underwent both insulin tolerance test and corticotropin-releasing-hormone stimulation. Using criteria for adequate cortisol response in serum, the patients were classified as good or poor responders. In 42 of the 45 tests performed the same conclusion as to cortisol status was drawn when based on serum and salivary cortisol responses. In healthy subjects and good responders the mean cortisol relative increase was greater in saliva than in serum in all three tests (p < 0.05). Characteristic of the results for the insulin tolerance test was a significant initial mean decrease (p < 0.05), not found in serum, and the highest observed salivary cortisol value was delayed for at least 30 minutes compared to that in serum. Plasma adreno-corticotrophic hormone correlated significantly with the cortisol concentrations determined 15 minutes later in serum (r = 0.54–0.64) and in saliva (r = 0.76–0.85). The more pronounced cortisol response in saliva than in serum and its closer correlation with adreno-corticotrophic hormone offer advantages over serum cortisol, suggesting salivary cortisol measurement may be used as an alternative parameter in dynamic endocrine tets.

  • 8. Alstergren, P
    et al.
    Ernberg, M
    Kopp, S
    Lundeberg, T
    Theodorsson, Elvar
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Östergötlands Läns Landsting, Centre for Laboratory Medicine, Department of Clinical Chemistry.
    TMJ pain in relation to circulating neuropeptide Y, serotonin, and interleukin-1 beta in rheumatoid arthritis.1999In: Journal of Orofacial Pain, ISSN 1064-6655, E-ISSN 1945-3396, Vol. 13, p. 49-55Article in journal (Refereed)
  • 9. Alstergren, P
    et al.
    Kopp, S
    Theodorsson, Elvar
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Östergötlands Läns Landsting, Centre for Laboratory Medicine, Department of Clinical Chemistry.
    Synovial fluid sampling fromthe temporomandibular joint: sample quality criteria and levels of interleukin-1 beta and serotonin.1999In: Acta Odontologica Scandinavica, ISSN 0001-6357, E-ISSN 1502-3850, Vol. 57, p. 16-22Article in journal (Refereed)
  • 10. Andreen Sachs, Magna
    et al.
    Theodorsson, Elvar
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Östergötlands Läns Landsting, Centre for Laboratory Medicine, Department of Clinical Chemistry.
    Övergripande kvalitetsindikatorer framtagna för hälso- och sjukvården2002In: Läkartidningen, ISSN 0023-7205, E-ISSN 1652-7518, Vol. 99, p. 797-803Article in journal (Other academic)
  • 11. Arnelo, Urban
    et al.
    Herrington, Margery
    Theodorsson, Elvar
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Östergötlands Läns Landsting, Centre for Laboratory Medicine, Department of Clinical Chemistry.
    Adrian, Thomas
    Reidelberger, Roger
    Larsson, Jörgen
    Marcusson, Jan
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Neuroscience and Locomotion, Geriatrics. Östergötlands Läns Landsting, MC - Medicincentrum, Geriatrik-LAH.
    Strömmer, Lisa
    Ding, Xianzhong
    Permert, Johan
    Effects of long-term infusion of anorexic concentrations of islet amyloid polypeptide on neurotransmitters and neuropeptides in rat brain.2000In: Brain Research, ISSN 0006-8993, E-ISSN 1872-6240, Vol. 887, p. 391-398Article in journal (Refereed)
  • 12.
    Bendtsen, Preben
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Department of Health and Society, Division of Preventive and Social Medicine and Public Health Science. Östergötlands Läns Landsting, Centre for Public Health Sciences, Centre for Public Health Sciences.
    Hultberg, J
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Department of Health and Society, Division of Preventive and Social Medicine and Public Health Science.
    Carlsson, M
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Department of Health and Society, Division of Preventive and Social Medicine and Public Health Science.
    Jones, A Wayne
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry.
    Monitoring ethanol exposure in a clinical setting by analysis of blood, breath, saliva, and urine.1999In: Alcoholism: Clinical and Experimental Research, ISSN 0145-6008, E-ISSN 1530-0277, Vol. 23, p. 1446-1451Article in journal (Refereed)
  • 13.
    Bengtson, Per
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Larson, Cecilia
    Institute of Laboratory Medicine, Department of Clinical Chemistry and Transfusion Medicine, Sahlgrenska University Hospital, Göteborg, Sweden.
    Lundblad, Arne
    Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Larson, Göran
    Institute of Laboratory Medicine, Department of Clinical Chemistry and Transfusion Medicine, Sahlgrenska University Hospital, Göteborg, Sweden.
    Påhlsson, Peter
    Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Identification of a Missense Mutation (G329A; Arg110→ Gln) in the Human FUT7 Gene2001In: Journal of Biological Chemistry, ISSN 0021-9258, E-ISSN 1083-351X, Vol. 276, no 34, p. 31575-31582Article in journal (Refereed)
    Abstract [en]

    The human FUT7 gene codes for the α1,3-fucosyltransferase VII (Fuc-TVII), which is involved in the biosynthesis of the sialyl Lewis x (SLex) epitope on human leukocytes. The FUT7 gene has so far been considered to be monomorphic. Neutrophils isolated from patients with ulcerative colitis were examined for apparent alterations in protein glycosylation patterns by Western blot analysis using monoclonal antibodies directed against SLex and SLex-related epitopes. One individual showed lower levels of SLex expression and an elevated expression of CD65s compared to controls. The coding regions of the FUT7 gene from this individual were cloned, and a G329A point mutation (Arg110 → Gln) was found in one allele, whereas the other FUT7 allele was wild type. No Fuc-TVII enzyme activity was detected in COS-7 cells transiently transfected with the mutated FUT7 construct. TheFUT7 Arg110 is conserved in all previously cloned vertebrate α1,3-fucosyltransferases. Polymerase chain reaction followed by restriction enzyme cleavage was used to screen 364 unselected Caucasians for the G329A mutation, and a frequency of ≤1% for this mutation was found (3 heterozygotes). Genetic characterization of the family members of one of the additional heterozygotes identified one individual carrying the G329A mutation in both FUT7alleles. Peripheral blood neutrophils of this homozygously mutated individual showed a lowered expression of SLex and an elevated expression of CD65s when analyzed by Western blot and flow cytometry. The homozygous individual was diagnosed with ulcer disease, non-insulin-dependent diabetes, osteoporosis, spondyloarthrosis, and Sjögren's syndrome but had no history of recurrent bacterial infections or leukocytosis.

  • 14.
    Bengtson, Per
    et al.
    Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Lundblad, Arne
    Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Larson, Göran
    Department of Clinical Chemistry and Transfusion Medicine, Institute of Laboratory Medicine, Sahlgrenska University Hospital, Göteborg, Sweden .
    Påhlsson, Peter
    Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Polymorphonuclear Leukocytes from Individuals Carrying the G329A Mutation in the α1,3-Fucosyltransferase VII Gene (FUT7) Roll on E- and P-Selectins2002In: Journal of Immunology, ISSN 0022-1767, E-ISSN 1550-6606, Vol. 169, no 7, p. 3940-3946Article in journal (Refereed)
    Abstract [en]

    We recently identified several individuals carrying a missense mutation (G329A; Arg110-Gln) in the FUT7 gene encoding fucosyltransferase VII. This enzyme is involved in the biosynthesis of the sialyl Lewis x (Lex) epitope on human leukocytes, which has been identified as an important component of leukocyte ligands for E- and P-selectin. No enzyme activity was measurable in expression studies in COS-7 cells using the mutated FUT7 construct. One of the identified individuals carried this mutation homozygously. Flow cytometry analysis of polymorphonuclear leukocytes (PMN) from this individual showed a nearly complete absence of staining with mAbs directed against sialyl Lex and a diminished staining with an E-selectin IgG chimera. However, staining with P-selectin IgG chimera and Abs directed against P-selectin glycoprotein ligand-1 was not affected by the mutation. PMN from the homozygously mutated individual was further analyzed in an in vitro flow chamber assay. The number of rolling PMN and the rolling velocities on both E- and P-selectin were in the range of PMN from nonmutated individuals. FUT4 and FUT7 mRNA was quantified in PMN isolated from individuals carrying the FUT7 mutation. It was found that PMN from both FUT7 homozygously and heterozygously mutated individuals exhibited an elevated expression of FUT4 mRNA compared with PMN from FUT7 nonmutated individuals. The elevated expression of fucosyltransferase IV was reflected as an increased expression of the Lex and CD65s Ags on PMN from these individuals. The significance of the mutation was supported by transfection of BJAB cells.

  • 15.
    Bengtson, Per
    et al.
    Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Zetterberg, Henrik
    Institute of Laboratory Medicine, Department of Clinical Chemistry and Transfursion Medicine, Sahlgrenska University Hospital, Göteborg, Sweden.
    Mellberg, Tomas
    Institute of Laboratory Medicine, Department of Clinical Chemistry and Transfursion Medicine, Sahlgrenska University Hospital, Göteborg, Sweden.
    Påhlsson, Peter
    Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Larson, Göran
    Institute of Laboratory Medicine, Department of Clinical Chemistry and Transfursion Medicine, Sahlgrenska University Hospital, Göteborg, Sweden.
    EBV-transformed B-cells from an individual homozygously mutated (G329A) in FUT7 do not roll on E-selectinManuscript (preprint) (Other academic)
    Abstract [en]

    The α1,3 fucosyltransferase VII (Fuc-TVII) is involved in the biosynthesis of E- and P-selectin ligands such as sialyl Lewis x on human leukocytes. Recently, individuals were characterized carrying a missense mutation (G329A; Arg110-Gln) in the FUT7 gene encoding this enzyme. The mutated FUT7 construct was not able to produce an active Fuc-TVII enzyme in transfection studies and polymorphonuclear granulocytes from an individual carrying the mutation homozygously showed severely reduced expression of sialyl Lewis x. In the present study we have established Epstein-Barr virus transformed B-celllines from this individual (SIGN) and from an individual not carrying the mutation (IWO). The cell lines were confirmed to be of B-cell origin by flow cytometry analysis. IWO cells interacted with E-selectin in an in vitro flow chamber analysis whereas SIGN cell did not. However, when SIGN cell were transfected with wild type FUT7 cDNA interaction with E-selectin could be restored. Cell surface expression of the sLex related epitopes recognized by antibodies CSLEX-1, KM-93 and HECA-452 was elevated on IWO cells compared to SIGN cells, consistent with a role of these antigens in E-selectin recognition. Despite high expression of PSGL-1 neither of the cell lines interacted with P-selectin under flow. These cell lines may be useful in the further characterization ofEselectin ligands and the obtained results encourage further studies on the consequences of the FUT7-G329A mutation in vivo.

  • 16. Bergström, J
    et al.
    Helander, A
    Jones, A Wayne
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry.
    Ethyl glucuronide concentrations in two successive urinary voids from drinking drivers: Relationship to creatinine content and blood and urine ethanol concentrations2003In: Forensic Science International, ISSN 0379-0738, E-ISSN 1872-6283, Vol. 133, no 1-2, p. 86-94Article in journal (Refereed)
    Abstract [en]

    The concentrations of alcohol in blood (BAC) and two successive urine voids (UAC) from 100 drunk drivers were compared with the concentration of ethyl glucuronide (EtG), a minor metabolite of ethanol in urine, and the urinary creatinine content as an indicator of dilution. The subjects consisted of 87 men with mean age 42.2 ▒ 14.2 years (▒standard deviation, S.D.) and 13 women with mean age 42.5 ▒ 14.4 years. Ethanol was measured in blood and urine by headspace gas chromatography (GC) and EtG was determined in urine by liquid chromatography-mass spectrometry (LC-MS). The mean UAC was 2.53 ▒ 1.15g/l for first void compared with 2.35 ▒ 1.17g/l for second void, decreasing by 0.18 ▒ 0.24g/l on average (P < 0.001 in paired t-test). The ratios of UAC/BAC were 1.35 ▒ 0.25 for first void and 1.20 ▒ 0.16 for second void and the difference of 0.15 ▒ 0.27 was statistically significant (P < 0.001). The UAC/BAC ratio was not correlated with creatinine content of the urine specimens, whereas the concentration of urinary EtG was positively correlated with creatinine (r=0.64 for first void and r=0.62 for second void). The UAC was not correlated with urinary EtG directly (r=-0.03 for first void and r=0.08 for second void) but after adjusting for the relative dilution of the specimens (EtG/creatinine ratio) statistically significant positive correlations were obtained (r=0.58 for first void and r=0.57 for second void). The dilution of the urine, as reflected in creatinine content, is important to consider when EtG measurements are interpreted. The excretion of EtG in urine, like glucuronide conjugates of other drugs, is influenced by diuresis. EtG represents a sensitive and specific marker of acute alcohol ingestion with applications in clinical and forensic medicine. ⌐ 2003 Elsevier Science Ireland Ltd. All rights reserved.

  • 17. Besselaar van den, AMHP
    et al.
    Houbouyan-Refeillard, LL
    Aillaud, MF
    Denson, KWE
    Johnston, M
    Kitchen, S
    Lindahl, Tomas
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Östergötlands Läns Landsting, Centre for Laboratory Medicine, Department of Clinical Chemistry.
    Multicenter evaluation of lyophilized and deep-frozen plasmas for assignment of the international normalized ratio.1999In: Thrombosis and Haemostasis, ISSN 0340-6245, E-ISSN 2567-689X, Vol. 82, p. 1451-1455Article in journal (Refereed)
  • 18. Bjellerup, P
    et al.
    Theodorsson, Elvar
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Östergötlands Läns Landsting, Centre for Laboratory Medicine, Department of Clinical Chemistry.
    Jörnvall, H
    Kogner, P
    Limited neuropeptide Y precursor processing in unfavourable metastatic neuroblastoma tumours2000In: British Journal of Cancer, ISSN 0007-0920, E-ISSN 1532-1827, Vol. 83, no 2, p. 171-176Article in journal (Refereed)
    Abstract [en]

    Neuropeptide Y (NPY) is found at high concentrations in neural crest-derived tumours and has been implicated as a regulatory peptide in tumour growth and differentiation. Neuroblastomas, ganglioneuromas and phaeochromocytomas with significant concentrations of NPY-like immunoreactivity were investigated for different molecular forms of NPY and for significance of proNPY processing. Gel-permeation chromatography identified intact NPY (1-36) in all tumours, whereas proNPY (69 amino acids) was detected only in control adrenal tissue and malignant neuroblastomas. Purification of NPY-like immunoreactivity in tumour extracts and structural characterization revealed that both NPY (1-36) and the truncated form NPY (3-36) was present. The degree of processing of proNPY to NPY in tumour tissue was lower in advanced neuroblastomas with regional or metastatic spread (stage 3 and 4) (n = 6), (41%, 12-100%, median, range), compared to the less aggressive stage 1, 2 and 4S tumours (n = 12), (93%, 69-100%), (P = 0.012). ProNPY processing of less than 50% was correlated with poor clinical outcome (P = 0.004). MYCN oncogene amplification was also correlated to a low degree of proNPY processing (P = 0.025). In summary, a low degree of proNPY processing was correlated to clinical advanced stage and poor outcome in neuroblastomas. ProNPY/NPY processing generated molecular forms of NPY with known differences in NPY-receptor selectivity, implicating a potential for in vivo modulation of NPY-like effects in tumour tissue. (C) 2000 Cancer Research Campaign.

  • 19. Boalth, Nicolas
    et al.
    Wandrup, Jesper
    Larsson, Lasse
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Östergötlands Läns Landsting, Centre for Laboratory Medicine, Department of Clinical Chemistry.
    Frischauf, Peter
    Lundsgaard, Finn
    Andersen, Willy
    Jensen, Niels-Henrik
    Singer, Rolf
    Troldborg, Carl
    Lunding, Gitte
    Blood gases and oximetry: calibration-free new dry-chemistry and optical technology for near-patíent testing.2001In: Clinica Chimica Acta, ISSN 0009-8981, E-ISSN 1873-3492, Vol. 307, p. 225-233Article in journal (Refereed)
  • 20. Bracci-Laudiero, Luisa
    et al.
    Aloe, Luigi
    Buanne, Pasquale
    Finn, Anja
    Stenfors, Carina
    Vigneti, Eliana
    Theodorsson, Elvar
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Östergötlands Läns Landsting, Centre for Laboratory Medicine, Department of Clinical Chemistry.
    Lundeberg, Thomas
    NGF modulates CGRP synthesis in human B-lymphocytes: A possible anti-inflammatory action of NGF?2002In: Journal of Neuroimmunology, ISSN 0165-5728, E-ISSN 1872-8421, Vol. 123, no 1-2, p. 58-65Article in journal (Refereed)
    Abstract [en]

    We investigated whether the sensory neuropeptide, calcitonin gene-related peptide (CGRP), could be synthesised by human lymphocytes. Our results indicate that in activated B-cells, there is a strong expression of CGRP gene transcripts, which is almost absent in resting cells. Since B-cells autocrinally produce NGF, the neutralisation of endogenous NGF by anti-NGF antibodies resulted in a marked reduction in CGRP expression in both resting and activated B-cells. Thus, NGF appears to directly affect the synthesis of CGRP in B-cells as in sensory neurons. By regulating CGRP synthesis in lymphocytes and neuronal cells, NGF can influence the intensity and duration of the immune response. ⌐ 2002 Elsevier Science B.V. All rights reserved.

  • 21. Bracci-Laudiero, Luisa
    et al.
    Aloe, Luigi
    Lundeberg, Thomas
    Theodorsson, Elvar
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Östergötlands Läns Landsting, Centre for Laboratory Medicine, Department of Clinical Chemistry.
    Stenfors, Carina
    Altered levels of neuropeptides characterize the brain of lupus prone mice.1999In: Neuroscience Letters, ISSN 0304-3940, E-ISSN 1872-7972, Vol. 273Article in journal (Refereed)
  • 22. Burnett, Robert W
    et al.
    D'Orazio, Paul
    Fogh-Andersen, Niels
    Kuwa, Katsuhiko
    Külpmann, Wolf
    Larsson, Lasse
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Östergötlands Läns Landsting, Centre for Laboratory Medicine, Department of Clinical Chemistry.
    Lewnstam, Andrzej
    Maas, Anton
    Mager, Gerhard
    Spichiger-Keller, Ursula
    IFCC recommendation on reporting results for blood glucose.2001In: Clinica Chimica Acta, ISSN 0009-8981, E-ISSN 1873-3492, Vol. 307, p. 205-209Article in journal (Refereed)
  • 23.
    Carlsson, Margaretha S.
    Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Linköping University, Department of Biomedicine and Surgery, Hematology. Linköping University, Department of Medicine and Care, Nephrology. Linköping University, Faculty of Health Sciences.
    Pharmacokinetics of 2-mercaptopropionylglycine (Tiopronin) in man1993Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    2-Mercaptopropionylglycine (2-MPG, tiopronin) has been used successfully in the treatment of cystinuria despite the lack of knowledge of its pharmacokinetics. Therefore methods based on high-performance liquid chromatography and fluorometric detection were developed for quantitative analysis. The total, non-protein-bound, and free (thiolic) tiopronin were measured in plasma using this method.

    The phannacokinetic disposition of tiopronin in plasma after intravenous administration was best described by a three exponential function. Plasma concentration time-curves of total tiopronin exhibited a rapid distribution phase, a B-phase corresponding to renal excretion, and a long terminal elimination phase. The latter was the result of strong disulphide binding of tiopronin to proteins. The non-protein-bound tiopronin was eliminated faster judging by its early appearance in urine. Mean bioavailability was 63 % in healthy volunteers with great interindividual variability (range 33-91%).

    Multiple dosing studies gave similar pharrnacokinetic parameters as for single dose studies and studies on patients with renal impaitment elucidated the renal clearance of the drug. In vitro studies showed a slow dissolution of the drug dosage form employed. A metabolite, 2-mercaptopropionic acid, was identified and its pharmacokinetics was investigated. The mechanism of action of the drug is discussed based on the results of measuring free tiopronin in plasma.

  • 24. Ceder, G
    et al.
    Jones, A Wayne
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry.
    Concentrations of unconjugated morphine, codeine, and 6-acetyl morphine in urine specimens from suspected drugged drivers.2002In: Journal of Forensic Sciences, ISSN 0022-1198, E-ISSN 1556-4029, Vol. 47, p. 366-368Article in journal (Refereed)
    Abstract [en]

    Concentrations of unconjugated morphine, codeine and 6-acetylmorphine (6-AM), the specific metabolite of heroin, were determined in urine specimens from 339 individuals apprehended for driving under the influence of drugs (DUID) in Sweden. After an initial screening analysis by immunoassay for 5-classes of abused drugs (opiates, cannabinoids, amphetamine analogs, cocaine metabolite and benzodiazepines), all positive specimens were verified by more specific methods. Opiates and other illicit drugs were analyzed by isotope-dilution gas chromatography-mass spectrometry (GC-MS). The limits of quantitation for morphine, codeine and 6-AM in urine were 20 ng/mL Calibration plots included an upper concentration limit of 1000 ng/mL for each opiate. We identified the heroin metabolite 6-AM in 212 urine specimens (62%) at concentrations ranging from 20 ng/mL to > 1000 ng/mL The concentration of 6-AM exceeded 1000 ng/mL in 79 cases (37%) and 31 cases (15%) were between 20 and 99 ng/mL. When 6-AM was present in urine the concentration of morphine was above 1000 ng/mL in 196 cases (92%). The concentrations of codeine in these same urine specimens were more evenly distributed with 35% being above 1000 ng/mL and 21% below 100 ng/mL. These results give a clear picture of the concentrations of unconjugated morphine, codeine and 6-acetylmorphine that can be expected in opiate-positive urine specimens from individuals apprehended for DUID after taking heroin.

  • 25. Ceder, Gunnel
    et al.
    Jones, A Wayne
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry.
    Concentration ratios of morphine to codeine in blood of impaired drivers as evidence of heroin use and not medication with codeine2001In: Clinical Chemistry, ISSN 0009-9147, E-ISSN 1530-8561, Vol. 47, no 11, p. 1980-1984Article in journal (Refereed)
    Abstract [en]

    Background: Both the illicit drug heroin and the prescription drug codeine are metabolized to morphine, which tends to complicate interpretation of opiate-positive samples. We report here the concentrations of morphine and codeine, the morphine/codeine ratios, and 6-acetylmorphine (6-AM) in blood specimens from individuals arrested for driving under the influence of drugs (DUID) in Sweden. The results were compared with positive findings of 6-AM in urine as evidence of heroin intake. Methods: In 339 DUID suspects, both blood and urine specimens were available for toxicologic analysis. In another 882 cases, only blood was available. All specimens were initially analyzed by immunoassay, and the positive results were verified by isotope-dilution gas chromatography-mass spectrometry. In routine casework, the limits of quantification (LOQs) for unconjugated opiates were 5 ng/g for blood and 20 ╡g/L for urine. Results: The median concentration of morphine in blood was 30 ng/g with 2.5 and 97.5 percentiles of 5 and 230 ng/g, respectively (n = 979). This compares with a median codeine concentration of 20 ng/g and 2.5 and 97.5 percentiles of 5 and 592 ng/g, respectively (n = 784). The specific metabolite of heroin, 6-AM, was identified in only 16 of 675 blood specimens (2.3%). This compares with positive findings of 6-AM in 212 of 339 urine samples (62%) from the same population of DUID suspects. When 6-AM was identified in urine, the morphine/codeine ratio in blood was always greater than unity (median, 6.0, range, 1-66). In 18 instances, 6-AM was present in urine, although morphine and codeine were below the LOQ in blood. The morphine/codeine ratio in blood was greater than unity in 85% of DUID cases when urine was not available (n = 506), and the median morphine and codeine concentrations were 70 ng/g and 10 ng/g, respectively. When morphine/codeine ratios in blood were less than unity (n = 76), the median morphine and codeine concentrations were 10 ng/g and 180 ng/g, respectively. Conclusions: Only 2.3% of opiate-positive DUID suspects were verified as heroin users on the basis of positive findings of 6-AM in blood. A much higher proportion (62%) were verified heroin users from 6-AM identified in urine. When urine was not available for analysis, finding a morphine/codeine concentration ratio in blood above unity suggests heroin use and not medication with codeine. This biomarker indicated that 85% of opiate-positive DUID blood samples were from heroin users. ⌐ 2001 American Association for Clinical Chemistry.

  • 26.
    Dahlin, Lars-Göran
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Thoracic Surgery. Östergötlands Läns Landsting, Heart Centre, Department of Thoracic and Vascular Surgery.
    Kågedahl, Bertil
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Östergötlands Läns Landsting, Centre for Laboratory Medicine, Department of Clinical Chemistry.
    Olin, Christian
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Thoracic Surgery. Östergötlands Läns Landsting, Heart Centre, Department of Thoracic and Vascular Surgery.
    Rutberg, Hans
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Anaesthesiology. Östergötlands Läns Landsting, Heart Centre, Department of Thoracic and Vascular Surgery.
    Svedjeholm, Rolf
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Thoracic Surgery. Östergötlands Läns Landsting, Heart Centre, Department of Thoracic and Vascular Surgery.
    An attempt to quantify the plasma levels of troponin-T and CK-MB after coronary surgery caused by release unrelated to permanent myocardial injury.2001In: Abstract 50th Annual meeting of the Scandinavian Association for Thoracic Surgery. June 14-16, 2001, Oslo, Norway,2001, 2001Conference paper (Refereed)
  • 27.
    Dahlin, Lars-Göran
    et al.
    Linköping University, Department of Medicine and Care, Thoracic Surgery. Linköping University, Faculty of Health Sciences.
    Kågedal, Bertil
    Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Nylander, Eva
    Linköping University, Department of Medicine and Care, Clinical Physiology. Linköping University, Faculty of Health Sciences.
    Olin, Christian
    Linköping University, Department of Medicine and Care, Thoracic Surgery. Linköping University, Faculty of Health Sciences.
    Rutberg, Hans
    Linköping University, Department of Medicine and Care, Anaesthesiology. Linköping University, Faculty of Health Sciences.
    Svedjeholm, Rolf
    Linköping University, Department of Medicine and Care, Thoracic Surgery. Linköping University, Faculty of Health Sciences.
    An attempt to quantify the plasma levels of troponin-T and CK-MB after coronary surgery caused by release unrelated to permanent myocardial injuryManuscript (preprint) (Other academic)
    Abstract [en]

    Background: Release of biochemical markers of myocardial injury unrelated to permanent myocardial damage has been claimed to explain a major proportion of elevations seen after cardiac surgery. However, little is known about the magnitude of this unspecific release. The aim of this study was to shed light on this issue by serial measurements in patients without permanent myocardial injury after coronary surgery.

    Methods: The unique release kinetics of troponin-T were employed to identify patients with no or minimal permanent myocardial injury. 302 patients undergoing CABG procedures (employing cardiopuhnonary bypass, crystalloid cardioplegia and retransfusion of shed mediastinal blood) were studied.

    Results: 90 patients were found to have normalized troponin-T levels no later than the fourth postoperative day indicating that early elevation of biochemical markers was explained almost purely by unspecific release. In this subgroup troponin-T (2.03±1.36 µg/L; range 0.35-8.99 µg/L) peaked at the 3 hour recording and CK-MB (28.3±10.7 µg/L; range 11.9-86 µg/L) peaked at the 8 hour recording after unclamping the aorta.

    Conclusions: A substantial early release of CK-MB and troponin-T occurred in patients with no or minimal permanent myocardial injury after CABG. The time frame when unspecific release was most pronounced is frequently studied to evaluate myocardial protective strategies or to compare different treatment modalities. Also, differences in unspecific release of biochemical markers can be expected depending on type of surgical procedure or coronary intervention. Therefore, further efforts to hring clarity about diagnostic pitfalls are warranted to prevent inappropriate comparisons and to improve our assessment of myocardial damage in association with revascularisation procedures.

  • 28.
    Dahlin, Lars-Göran
    et al.
    Linköping University, Department of Medicine and Care, Thoracic Surgery. Linköping University, Faculty of Health Sciences.
    Kågedal, Bertil
    Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Nylander, Eva
    Linköping University, Department of Medicine and Care, Clinical Physiology. Linköping University, Faculty of Health Sciences.
    Olin, Christian
    Linköping University, Department of Medicine and Care, Clinical Physiology. Linköping University, Faculty of Health Sciences.
    Rutberg, Hans
    Linköping University, Department of Medicine and Care, Anaesthesiology. Linköping University, Faculty of Health Sciences.
    Svedjeholm, Rolf
    Linköping University, Department of Medicine and Care, Thoracic Surgery. Linköping University, Faculty of Health Sciences.
    Early Identification of Permanent Myocardial Damage after Coronary Surgery is Aided by Repeated Measurements of CK-MB2002In: Scandinavian Cardiovascular Journal, ISSN 1401-7431, E-ISSN 1651-2006, Vol. 36, no 1, p. 35-40Article in journal (Refereed)
    Abstract [en]

    Objective - ECG diagnosis of myocardial infarction after cardiac surgery is associated with major pitfalls and enzyme diagnosis is interfered by unspecific elevation unrelated to permanent myocardial injury. Sustained release of troponin-T is a marker of permanent myocardial injury if renal function is maintained. However, early identification of perioperative myocardial infarction is desirable and therefore the usefulness of creatine kinase monobasic (CK-MB) kinetics to detect myocardial injury early after coronary surgery was investigated.

    Design - Two hundred and eighty-six patients undergoing coronary surgery were studied with respect to release of enzymes and troponin-T preoperatively and postoperatively 3 and 8 h after unclamping the aorta, and every morning postoperative days 1-4.

    Results - CK-MB peak was found at 3 h ( n = 145), 8 h ( n = 103) and 16-20 h after unclamping ( n = 38). Depending on when the CK-MB peak was recorded different demographic and perioperative characteristics were found. A sustained release of troponin-T was characteristic for the group with the CK-MB peak at 16-20 h after unclamping.

    Conclusion - If CK-MB is measured only once it may be advisable to do it on the first postoperative morning as these measurements provided the best discrimination between patients with and without sustained elevation of troponin-T. However, repeated sampling provides additional information that aids in the early identification of permanent myocardial injury particularly in patients with borderline elevations of CK-MB.

  • 29.
    Dahlin, Lars-Göran
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Thoracic Surgery. Östergötlands Läns Landsting, Heart Centre, Department of Thoracic and Vascular Surgery.
    Kågedal, Bertil
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Östergötlands Läns Landsting, Centre for Laboratory Medicine, Department of Clinical Chemistry.
    Nylander, Eva
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Olin, Christian
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Thoracic Surgery.
    Rutberg, Hans
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Anaesthesiology. Östergötlands Läns Landsting, Heart Centre, Department of Thoracic and Vascular Surgery.
    Svedjeholm, Rolf
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Thoracic Surgery. Östergötlands Läns Landsting, Heart Centre, Department of Thoracic and Vascular Surgery.
    Unspecific elevation of plasma troponin-T and CK-MB after coronary surgery2003In: Scandinavian Cardiovascular Journal, ISSN 1401-7431, E-ISSN 1651-2006, Vol. 37, no 5, p. 283-287Article in journal (Refereed)
    Abstract [en]

    Objective - Biochemical markers of myocardial injury are frequently elevated after cardiac surgery. It is generally accepted that release unrelated to permanent myocardial damage explains a proportion of these elevations. However, little is known about the magnitude and temporal characteristics of this diagnostic noise. One way to address this issue would be to study a group without permanent myocardial injury. Design - The unique release kinetics of troponin-T (permanent myocardial injury causes a sustained release of structurally bound troponin) were used to identify patients with no or minimal permanent myocardial injury. Blood was sampled from patients undergoing coronary artery bypass grafting (CABG) with cardiopulmonary bypass (CPB) before surgery, 3 and 8 h after unclamping the aorta, and each morning until postoperative day 4, for analysis of enzymes and troponin-T. From 302 consecutive patients a subgroup was identified that fulfilled the following criteria: (a) normalized troponin-T levels =postoperative day 4, (b) no ECG changes indicating myocardial injury. Results - Seventy-seven patients fulfilled the criteria above and in this subgroup troponin-T (2.08 ▒ 1.42 ╡g/ 1, range 0.35-8.99 ╡g/l) peaked at the 3 h recording and creatine kinase monobasic (CK-MB) (28.6 ▒ 11.3 ╡g/l, range 11.9-86.0 ╡g/l) peaked at the 8 h recording after unclamping the aorta. Conclusion - Substantial early elevations of plasma CK-MB and troponin-T occurred in patients with no or minimal permanent myocardial injury after CABG. Unspecific release was most pronounced during the timeframe that is usually studied to evaluate myocardial protective strategies or to compare revascularization procedures.

  • 30. Dawidson, I
    et al.
    Angmar-Mansson, B
    Blom, M
    Theodorsson, Elvar
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Östergötlands Läns Landsting, Centre for Laboratory Medicine, Department of Clinical Chemistry.
    Lundeberg, T
    Sensory stimulation (acupuncture) increases the release of calcitonin gene-related peptide in the saliva os xerostomia sufferers.1999In: Neuropeptides, ISSN 0143-4179, E-ISSN 1532-2785, Vol. 33, p. 244-250Article in journal (Refereed)
  • 31.
    Dizdar (Dizdar Segrell), Nil
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Östergötlands Läns Landsting, Centre for Laboratory Medicine, Department of Clinical Chemistry.
    Årstrand, Kerstin
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry.
    Kågedal, Bertil
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Östergötlands Läns Landsting, Centre for Laboratory Medicine, Department of Clinical Chemistry.
    Analysis of L-dopa in human serum2002In: BioTechniques, ISSN 0736-6205, E-ISSN 1940-9818, Vol. 33, no 5, p. 1000-1002Article in journal (Refereed)
  • 32.
    Druid, H
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Molecular and Clinical Medicine, Forensic Medicine.
    Holmgren, P
    Carlsson, B
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Östergötlands Läns Landsting, Centre for Laboratory Medicine, Department of Clinical Chemistry.
    Ahlner, Johan
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Pharmacology.
    Cytochrome P450 2D6 (CYPP2D6) genotyping on postmortem blood as a supplementary tool for interpretation of forensic toxicological results.  1999In: Forensic Science International, ISSN 0379-0738, E-ISSN 1872-6283, Vol. 99, p. 25-34Article in journal (Refereed)
  • 33. Egberg, N
    et al.
    Hillarp, A
    Johnsson, H
    Lindahl, Tomas
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Östergötlands Läns Landsting, Centre for Laboratory Medicine, Department of Clinical Chemistry.
    Stigendal, L
    Protrombinkomplexmätning bör anges som en kvot, inte i procent.1999In: Läkartidningen, ISSN 0023-7205, E-ISSN 1652-7518, Vol. 96, p. 2489-2491Article in journal (Other (popular science, discussion, etc.))
  • 34. Egberg, N
    et al.
    Hillarp, A
    Johnsson, H
    Lindahl, Tomas
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Östergötlands Läns Landsting, Centre for Laboratory Medicine, Department of Clinical Chemistry.
    Stigendal, S
    Nya svarsrutiner för protrombinkomplex.1999In: Vårdfacket, ISSN 0347-0911, Vol. 5, p. 44-46Article in journal (Other (popular science, discussion, etc.))
  • 35. Egberg, N
    et al.
    Hillarp, A
    Johnsson, H
    Lindahl, Tomas
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Östergötlands Läns Landsting, Centre for Laboratory Medicine, Department of Clinical Chemistry.
    Stigendal, S
    Protrombinkomplexmetoden förändras. Svar i % ersätts med INR.1999In: Laboratoriet, ISSN 0345-696X, Vol. 3Article in journal (Other (popular science, discussion, etc.))
  • 36. Eriksson, Mats
    et al.
    Christensen, Kjeld
    Lindahl, Tomas
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Östergötlands Läns Landsting, Centre for Laboratory Medicine, Department of Clinical Chemistry.
    Larsson, Anders
    Pharmaceutical thrombosis prevention in cardiovascular disease2002In: Expert Opinion on Investigational Drugs, ISSN 1354-3784, E-ISSN 1744-7658, Vol. 11, p. 553-563Article in journal (Refereed)
  • 37.
    Evaldsson, Chamilly
    et al.
    Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Rydén, I.
    Division of Clinical Chemistry, Kalmar County Hospital, 391 85 Kalmar, Sweden.
    Uppugunduri, Srinivas
    Linköping University, Department of Biomedicine and Surgery, Division of clinical chemistry. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre for Laboratory Medicine, Department of Clinical Chemistry.
    Anti-inflammatory effects of exogenous uridine in an animal model of lung inflammation.2007In: International Immunopharmacology, ISSN 1567-5769, E-ISSN 1878-1705, Vol. 7, no 8, p. 1025-1032Article in journal (Refereed)
    Abstract [en]

    Nucleosides like adenosine, uridine and their nucleotide derivatives (e.g. ATP and UTP) play important roles in many cellular functions, sometimes by acting as signalling molecules through binding to specific P2 nucleotide receptors. P2 receptors are subdivided into P2X and P2Y subfamilies, the latter of which are G-protein coupled receptors. P2Y receptors and nucleoside transporters have been detected in human and rat lungs, where they mediate effects of interest in airway diseases. The aim of this study was to investigate whether uridine has any anti-inflammatory properties in an asthma-like animal model of lung inflammation.

    The Sephadex-induced lung inflammation model in Sprague-Dawley rats was chosen mainly due to its localised inflammatory response and uridine's limited oral bioavailability. The dextran beads, with or without the addition of uridine, were instilled intratracheally into the lungs, which were excised and examined after 24 h.

    Sephadex alone led to massive oedema and infiltration of macrophages, neutrophils and eosinophils. Microgranulomas with giant cell formations were clearly visible around the partially degraded beads. Uridine reduced both the oedema and the infiltration of leukocytes significantly, measured as lung wet weight and leukocyte counts in bronchoalveolar lavage fluid, respectively. Uridine appeared to affect the tumour necrosis factor (TNF) levels, although this could not be statistically confirmed due to large variations within the Sephadex control group.

    We conclude that uridine has anti-inflammatory effects, and that the exact mechanism(s) of action requires further study.

  • 38.
    Farnebäck, Malin
    Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Quantitative analysis of melanoma transcripts: with emphasis on methodological and biological variation2004Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The introduction of RT-PCR made it possible to detect circulating tumor cells in melanoma patients by analysis of melanoma-associated transcripts, especially tyrosinase. Since the development of the first PCR method for tyrosinase mRNA, several studies have presented varying results. In the present thesis I have developed and used quantitative PCR methods in order to evaluate methodological and biological factors which may explain the disparity in the literature.

    Two methods were developed for tyrosinase, one competitive PCR and one real-time PCR method. With the real-time PCR technique, quantitative methods were also developed for tyrosinase related protein (TRP)-1, TRP-2, MART-1/Melan-A, S-100, GD2 synthase, MAGE-A3 and MAGE-A12. Methodological studies on the RNA extraction showed that the silica based RNA extraction method QIAamp gave considerably higher yields compared with the phenol-chloroform based extraction methods Ultraspec and FastRNA. Further studies showed that yields comparable with the QIAamp method could be obtained with the mRNA extraction method GenoPrep. Optimization of the cDNA synthesis procedure revealed that the reverse transcriptase and factors in the RNA sample inhibited the following PCR. This was avoided by diluting the cDNA sample before PCR.

    The stability of the tumor cell RNA in the samples is of great concern when it comes to transporting samples from distant hospitals to the laboratory. It was found that blood collected in ACD was best, although insufficiently, stabilized when stored at +4 °C compared with room temperature. Similar stability was also obtained for PAXgene tubes stored at room temperature, however the stability of RNA was much improved when the PAXgene tubes were frozen.

    Studies on the biological variation in cultured melanoma cell lines and tissue sections from melanoma metastases showed that the expression of melanoma associated transcripts varied widely. In melanoma cell lines the expression of the transcripts tyrosinase, TRP-1, TRP-2 and MART-1/Melan-A was related to the pigmentation of the cell lines. The pigment-related transcripts and S-100 were expressed at higher levels than GD2 synthase, MAGE-A3 and MAGE-A12 in the melanoma metastases. The expressions of TRP-2 and GD2 synthase appeared to be influenced by therapy. In metastases from patients treated with a combination of cisplatinum, DTIC and interferon-α2b, TRP-2 was expressed at higher levels and GD2 synthase at lower levels compared with untreated patients.

    List of papers
    1. Quantitative analysis of tyrosinase transcripts in blood
    Open this publication in new window or tab >>Quantitative analysis of tyrosinase transcripts in blood
    Show others...
    2000 (English)In: Clinical Chemistry, ISSN 0009-9147, E-ISSN 1530-8561, Vol. 46, no 7, p. 921-927Article in journal (Refereed) Published
    Abstract [en]

    Background: Tyrosinase is an enzyme unique to pigment-forming cells. Methods using this transcript for detection of melanoma cells in blood have given divergent results. Quantitative analytical procedures are therefore needed to study the analytical performance of the methods.

    Methods: Mononucleated cells were isolated by Percoll centrifugation. RNA was isolated by each of three methods: UltraspecTM-II RNA isolation system, FastRNATM GREEN Kit, and QIAamp RNA Blood Mini Kit. cDNA was synthesized using random hexamer primers. A tyrosinase-specific product of 207 bp was amplified by PCR. As an internal standard (and competitor) we used a 207-bp cDNA with a base sequence identical to the tyrosinase target except for a 20-bp probe-binding region. The PCR products were identified by 2,4-dinitrophenol (DNP)-labeled probes specific for tyrosinase (5′DNP-GGGGAGCCTTGGGGTTCTGG-3′) and internal standard (5′DNP-CGGAGCCCCGAAACCACATC-3′) and quantified by ELISA.

    Results: The calibration curves were linear and had a broad dynamic measuring range. A detection limit (2 SD above zero) of 48 transcripts/mL of blood was obtained from a low control. The analytical imprecision was 50% and 48% at concentrations of 1775 and 17 929 transcripts/mL (n = 12 and 14, respectively). With the cell line SK-Mel 28 added to blood and RNA extracted with the Ultraspec, Fast RNA, and QIAamp RNA methods, we found (mean ± SD) 1716 ± 1341, 2670 ± 3174, and 24 320 ± 5332 transcripts/mL of blood. Corresponding values were 527 ± 497, 2497 ± 1033, 14 930 ± 1927 transcripts/mL of blood when the cell line JKM86-4 was added. One high-risk patient was followed by repeated analysis of tyrosinase transcripts in blood. The melanoma marker 5-S-cysteinyldopa in serum and urine was within reference values, but tyrosinase mRNA was slightly increased (120–168 transcripts/mL of blood). The tyrosinase mRNA increased to 1860 transcripts/mL concomitant with the increase in 5-S-cysteinyldopa; later a spleen metastasis was found.

    Conclusions: The results obtained with different RNA extraction methods illustrate the importance of quantitative methods for validation of methods. The use of QIAamp RNA improved the extraction efficiency considerably. Data from a case study suggest the assay is suitable in the follow-up of patients with high risk of developing metastases.

    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-25119 (URN)9552 (Local ID)9552 (Archive number)9552 (OAI)
    Available from: 2009-10-07 Created: 2009-10-07 Last updated: 2017-12-13
    2. Quantitative analysis of tyrosinase and tyrosinase-related protein-2 mRNA from melanoma cells in blood by real-time polymerase chain reaction
    Open this publication in new window or tab >>Quantitative analysis of tyrosinase and tyrosinase-related protein-2 mRNA from melanoma cells in blood by real-time polymerase chain reaction
    Show others...
    2000 (English)In: Melanoma research, ISSN 0960-8931, E-ISSN 1473-5636, Vol. 10, no 3, p. 213-222Article in journal (Refereed) Published
    Abstract [en]

    Several studies have evaluated the use of polymerase chain reaction (PCR) amplification of tyrosinase mRNA to detect melanoma cells in blood. However, contradictory results have been obtained from different groups. We therefore have developed and validated a quantitative PCR method for tyrosinase and tyrosinase-related protein-2 (TRP-2) mRNA. An important methodological finding was that high concentrations of reverse transcriptase or RNA sample inhibited the following PCR. This could be abolished by dilution of the cDNA sample before the PCR. Standard curves with a linear range over at least five logs were obtained with dilutions of melanoma cell cDNA. Controls (RNA and cDNA) consisting of melanoma cells (1000/ml) added to blood were analysed repeatedly over 3 months, resulting in means between 880 and 1074 AU/ml. The RNA controls were stable, whereas the cDNA controls, as well as the calibrators, showed a tendency to change over time. The variation in the RNA controls was 25% for tyrosinase and 22% for TRP-2. Seven stage III-IV melanoma patients were tested for tyrosinase and TRP-2 transcripts in blood drawn from a peripheral vein and from a Port-a-cath. Tyrosinase mRNA was found in three patients (0.8-12.4 AU/ml). For TRP-2, the same amount was found in the patients as in healthy donors. No differences were seen between blood from a peripheral vein and from the Port-a-cath. We here present fast and sensitive methods for the quantification of tyrosinase and TRP-2 mRNA in blood.

    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-25089 (URN)10890374 (PubMedID)9520 (Local ID)9520 (Archive number)9520 (OAI)
    Available from: 2009-10-07 Created: 2009-10-07 Last updated: 2017-12-13
    3. Stability of blood samples for analysis of tumour cell transcripts
    Open this publication in new window or tab >>Stability of blood samples for analysis of tumour cell transcripts
    (English)Manuscript (preprint) (Other academic)
    Abstract [en]

    When mRNA expression from tumor cells is analyzed in blood, one of the greatest problems is to keep the samples stable during transfer to the laboratory. Improved systems for stabilization of transcripts therefore have to be developed.

    Blood was collected in PAXgene™ Blood RNA Tubes and spiked with melanoma and neuroblastoma cells. The stability of tumor transcripts at room temperature was tested after 1, 2, 3, 5, 7, and 9 days. PAXgene tubes were also frozen at -20 °C and -70 °C for 14 days. Total RNA was extracted by PAXgene™ Blood RNA Kit and mRNA was extracted by the GenoPrep Direct mRNA Kit. Tyrosinase, MAGE, tyrosine hydroxylase, and GD2 synthase mRNA was quantified by real-time PCR. The stability of these transcripts was compared with the stability in ACD tubes when RNA extraction was performed with QIAamp RNA Blood Mini Kit.

    The yields of transcripts from the PAXgene tubes using the PAXgene™ Blood RNA Kit varied from 37% to 49% of the yields from ACD tubes. When mRNA was extracted with the GenoPrep Direct mRNA Kit the yields increased to 67-121%. Stability tests showed significant decreases of all the transcripts in the PAXgene tubes after two days at room temperature. After seven days, 10% of the initial transcript concentrations remained, whereas 32% remained in the ACD tubes. However, in the frozen PAXgene tubes the transcript levels were unchanged for 14 days.

    We conclude that the PAXgene tube is suitable when the sample is stored at -20 °C or -70 °C and mRNA is extracted using GenoPrep Direct mRNA Kit.

    Keywords
    RNA stability, real-time PCR, blood sampling, preanalytics, minimal residual disease
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-84993 (URN)
    Available from: 2012-10-30 Created: 2012-10-30 Last updated: 2012-10-30
    4. Quantitative relationships between pigment-related mRNA and biochemical melanoma markers in melanoma cell lines
    Open this publication in new window or tab >>Quantitative relationships between pigment-related mRNA and biochemical melanoma markers in melanoma cell lines
    Show others...
    2002 (English)In: Melanoma research, ISSN 0960-8931, E-ISSN 1473-5636, Vol. 12, no 3, p. 193-200Article in journal (Refereed) Published
    Abstract [en]

    The use of reverse transcription polymerase chain reaction (RT-PCR) analysis of melanoma-specific transcripts for the identification of circulating melanoma cells has shown very variable results in different studies on melanoma patients. We have therefore developed quantitative methods to study both analytical and biological variations as possible causes of this phenomenon. Pigment-related and S-100β transcripts were quantified in 12 different melanoma cell lines and related to the amounts of 5-S-cysteinyldopa, pigment and S-100B protein. A real-time PCR method was used and the results were expressed as absolute number of transcripts per cell. Tyrosinase, tyrosinase-related protein (TRP)-1, TRP-2 and MART-1/Melan-A mRNA varied from undetectable (< 10-4 transcripts/cell) to 103 transcripts/cell, i.e. by a factor > 107 in the different cell lines. S-100β mRNA varied from 2.8 to 165 transcripts/cell, i.e. by a factor of 60. Tyrosinase, TRP-1 and TRP-2 mRNA correlated significantly with the amount of 5-S-cysteinyldopa, an intermediate pigment metabolite (P < 0.001, P < 0.001 and P < 0.01, respectively). The amount of S-100β mRNA correlated significantly with the amount of S-100B protein (P < 0.001). No cross-correlations were seen between the pigment-related and S-100-related analytes. We conclude that one reason behind the negative results of RT-PCR measurement of pigment-related mRNA may be that these transcripts are not always expressed in the particular cells present in the patient's blood. Furthermore, variation in the expression of the order of 107 must have great impact on the diagnostic sensitivity. Measurement of S-100β mRNA would be more sensitive, but the use of this transcript is hampered by its presence in the blood cells. © 2002 Lippincott Williams & Wilkins.

    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-25118 (URN)10.1097/00008390-200206000-00002 (DOI)12140375 (PubMedID)9551 (Local ID)9551 (Archive number)9551 (OAI)
    Available from: 2009-10-07 Created: 2009-10-07 Last updated: 2017-12-13
    5. How useful are housekeeping genes?: variable expression in melanoma metastases
    Open this publication in new window or tab >>How useful are housekeeping genes?: variable expression in melanoma metastases
    Show others...
    2007 (English)In: Clinical Chemistry and Laboratory Medicine, ISSN 1434-6621, E-ISSN 1437-4331, Vol. 45, no 11, p. 1481-1487Article in journal (Refereed) Published
    Abstract [en]

    Background: There is a certain difference in opinion regarding the optimal choice of housekeeping genes used as normalization factors in gene expression analysis. We have therefore examined the suitability of three housekeeping genes, hypoxanthine phosphoribosyl transferase, β-glucuronidase and β2-micro-globulin, for normalization of expression data from melanoma metastases.

    Methods: The expression of the three housekeeping genes was quantified by quantitative reverse transcription PCR in snap-frozen sections from 44 melanoma metastases, of which 19 were from patients treated with cisplatinum, dacarbazine and interferon-α2b.

    Results: The expression of each housekeeping gene varied considerably between the different metastases. Histopathological examination of the tissue sections revealed variation in the amount of tumor cells in the tissue, necrosis, varying degrees of lymphocyte infiltration, and lymph node remnants. Based on this examination, 16 biopsies were omitted from further analysis because they had cracked, contained empty or necrotic areas, or were dominated by lymph node tissue. Even in sections with more than 90% tumor cells, a wide variation in the expression of the three housekeeping genes was found. The amount of lymphatic infiltrate in the tumors can have an effect on the expression of housekeeping genes in the meta-stases, whereas treatment did not seem to influence the expression.

    Conclusions: We conclude that the choice of housekeeping genes can have great impact on the normalization of specific genes in melanoma metastases. Furthermore, in the analysis of mRNA expression in tumor tissue, microscopic examination is of great importance to evaluate the integrity and cellular composition of the biopsy.

    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-39472 (URN)10.1515/CCLM.2007.303 (DOI)48767 (Local ID)48767 (Archive number)48767 (OAI)
    Available from: 2009-10-10 Created: 2009-10-10 Last updated: 2017-12-13
    6. Expression of tumor associated transcripts in malignant melanoma metastases: with methodological aspects
    Open this publication in new window or tab >>Expression of tumor associated transcripts in malignant melanoma metastases: with methodological aspects
    Show others...
    (English)Manuscript (preprint) (Other academic)
    Abstract [en]

    Several antigens expressed in malignant melanoma are involved in the immunological surveillance of the tumor. The mRNAs of these antigens, especially tyrosinase, have also been used in the detection of minimal residual disease in the blood of melanoma patients. We have therefore analyzed the expression of tyrosinase, TRP-1, TRP-2, MART-1/Melan-A, MAGE-A3, MAGE-A12, S-100 and GD2 synthase by real-time PCR in snap frozen sections from 28 regional and systemic metastases. Treatment with cisplatinum, dacarbazine and interferon-α2b was given to 15 patients before surgery. The transcript concentrations varied widely between individual metastases. However, in general the pigment-related transcripts and that of S-100 were found at higher levels than those of MAGE-A3, MAGE-A12 and GD2 synthase. Significant correlations (p<0.001) were found between tyrosinase and MART-1/Melan-A and between MAGE-A3 and MAGE-A12. TRP-2 and GD2 synthase were both influenced by the treatment, TRP-2 expression was increased in the metastases from treated patients, whereas GD2 synthase expression was decreased. Furthermore, a decrease in tyrosinase expression was found in metastases without tumor-infiltrating lymphocytes. ln this work normalization by the section area contra normalization by housekeeping genes was also evaluated and similar results were obtained with both methods.

    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-84994 (URN)
    Available from: 2012-10-30 Created: 2012-10-30 Last updated: 2012-10-30
  • 39.
    Farnebäck, Malin
    et al.
    Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Håkansson, Annika
    Linköping University, Department of Biomedicine and Surgery, Oncology. Linköping University, Faculty of Health Sciences.
    Håkansson, Leif
    Linköping University, Department of Biomedicine and Surgery, Oncology. Linköping University, Faculty of Health Sciences.
    Gustafsson, Bertil
    Östergötlands Läns Landsting, Centre for Laboratory Medicine, Department of Clinical Pathology and Cytology. Linköping University, Faculty of Health Sciences.
    Kågedal, Bertil
    Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Expression of tumor associated transcripts in malignant melanoma metastases: with methodological aspectsManuscript (preprint) (Other academic)
    Abstract [en]

    Several antigens expressed in malignant melanoma are involved in the immunological surveillance of the tumor. The mRNAs of these antigens, especially tyrosinase, have also been used in the detection of minimal residual disease in the blood of melanoma patients. We have therefore analyzed the expression of tyrosinase, TRP-1, TRP-2, MART-1/Melan-A, MAGE-A3, MAGE-A12, S-100 and GD2 synthase by real-time PCR in snap frozen sections from 28 regional and systemic metastases. Treatment with cisplatinum, dacarbazine and interferon-α2b was given to 15 patients before surgery. The transcript concentrations varied widely between individual metastases. However, in general the pigment-related transcripts and that of S-100 were found at higher levels than those of MAGE-A3, MAGE-A12 and GD2 synthase. Significant correlations (p<0.001) were found between tyrosinase and MART-1/Melan-A and between MAGE-A3 and MAGE-A12. TRP-2 and GD2 synthase were both influenced by the treatment, TRP-2 expression was increased in the metastases from treated patients, whereas GD2 synthase expression was decreased. Furthermore, a decrease in tyrosinase expression was found in metastases without tumor-infiltrating lymphocytes. ln this work normalization by the section area contra normalization by housekeeping genes was also evaluated and similar results were obtained with both methods.

  • 40.
    Farnebäck, Malin
    et al.
    Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Kullman, Anita
    Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Kågedal, Bertil
    Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Stability of blood samples for analysis of tumour cell transcriptsManuscript (preprint) (Other academic)
    Abstract [en]

    When mRNA expression from tumor cells is analyzed in blood, one of the greatest problems is to keep the samples stable during transfer to the laboratory. Improved systems for stabilization of transcripts therefore have to be developed.

    Blood was collected in PAXgene™ Blood RNA Tubes and spiked with melanoma and neuroblastoma cells. The stability of tumor transcripts at room temperature was tested after 1, 2, 3, 5, 7, and 9 days. PAXgene tubes were also frozen at -20 °C and -70 °C for 14 days. Total RNA was extracted by PAXgene™ Blood RNA Kit and mRNA was extracted by the GenoPrep Direct mRNA Kit. Tyrosinase, MAGE, tyrosine hydroxylase, and GD2 synthase mRNA was quantified by real-time PCR. The stability of these transcripts was compared with the stability in ACD tubes when RNA extraction was performed with QIAamp RNA Blood Mini Kit.

    The yields of transcripts from the PAXgene tubes using the PAXgene™ Blood RNA Kit varied from 37% to 49% of the yields from ACD tubes. When mRNA was extracted with the GenoPrep Direct mRNA Kit the yields increased to 67-121%. Stability tests showed significant decreases of all the transcripts in the PAXgene tubes after two days at room temperature. After seven days, 10% of the initial transcript concentrations remained, whereas 32% remained in the ACD tubes. However, in the frozen PAXgene tubes the transcript levels were unchanged for 14 days.

    We conclude that the PAXgene tube is suitable when the sample is stored at -20 °C or -70 °C and mRNA is extracted using GenoPrep Direct mRNA Kit.

  • 41. Fogh-Andersen, Niels
    et al.
    D´Orazio, Paul
    Kuwa, Katsuhiko
    Külpmann, Wolf R
    Mager, Gerhard
    Larsson, Lasse
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Östergötlands Läns Landsting, Centre for Laboratory Medicine, Department of Clinical Chemistry.
    Recommendation on reporting results for blood glucose (from an IFCC stage 1 document) IFCC scientific division working group on selective electrodes2002In: The Journal of the International Federation of Clinical Chemistry and Laboratory Medicine, ISSN 1051-2292, Vol. 12Article in journal (Refereed)
  • 42.
    Hansson, Kenny
    Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Real-time analysis of blood coagulation and fibrinolysis: new rheological and optical sensing techniques for diagnosis of haemostatic disorders.2001Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The haemostatic system has a dual paradoxical function in the body. It should arrest bleeding whenever needed, but also keep the blood flowing in the circulatory system without any obstructing blood clots. The system is complex with maoy intertwined processes that interact to produce a fine-tuned regulation of the performance. In case of malfunction in this regulation there may be an excessive coagulation ability, thrombophilia, or bleeding tendency, haemophilia. These are common disorders in the Western societies and may be lethal. The long-term airo of this work is therefore to improve the laboratory diagnosis of haemostatic disorders, for thrombophilia in particular. To achieve this goal a global approach has been chosen, meaning that the environment in which a blood sample is analysed should mimic the physiology of the haemostatic system to better elucidate the overall situation in a particular individual. A first attempt to assess the susceptibility for tissue plasminogen activator induced lysis and coagulum structure in plasma as markers for deep vein thrombosis showed promising results with 47% abnormals among the DVT patients included in the study. To improve this assay new sensing techniques were needed, since one of the most important conditions included in a global assay is analysis of whole blood, i.e. blood with all types of blood cells present. Whole blood is opaque and excludes the traditional optical methods that have been used for coagulation analysis. Several candidate techniques have been identified and surface plasmon resonance (SPR), quartz crystal microbalance-dissipation (QCM-D), and free oscillation rheometry (FOR) have been evaluated for haemostatic studies in this thesis. SPR is an optical surface sensitive technique that has showed promising results for measurements in blood plasma during coagulation and fibrinolysis and for whole blood coagulation. The SPR responses were sensitive to treatments with heparin and oral anticoagulants, which are substances used to treat thrombosis. QCM-D that is sensitive to mass deposition and viscoelastic changes in the sample at the quartz crystal surface has been tested in combination with SPR and provided new information about the viscoelastic properties of the coagulum, although with similar sensing depth as SPR. The idea of combined sensing techniques was reconsidered and resulted in a combination of SPR and FOR for siroultaneous real-time measurements in a blood sample. FOR is bulk sensitive and probes rheological changes in the sample. The combination was applied in studies of plasma and whole blood coagulation as well as plasma fibrinolysis. Coagulation studies including chemical surface modifications by using thiol-based self-assembled monolayers were also attempted. Finally, the FOR/SPR combination was found to be sensitive to inhibition of platelet aggregation and blood cell shape changes iroplying that studies on the cellular component of the blood is possible. In conclusion, the combination of FOR and SPR is a promising sensing system for an improved global assay for haemostatic disorders.

    List of papers
    1. Abnormalities in coagulum lysis and structure are associated with deep venous thrombosis
    Open this publication in new window or tab >>Abnormalities in coagulum lysis and structure are associated with deep venous thrombosis
    (English)Manuscript (preprint) (Other academic)
    Abstract [en]

    The present study aimed to investigate the relationship between deep venous thrombosis (DVT) and fibrinolytic susceptibility of plasma coagulum, including the possible role of this property in laboratory diagnosis. From 276 patients consecutively admitted to hospital for suspected deep venous thrombosis (DVT), 75 patients and 47 controls were selected. With certainty, the patients and controls either had or did not have DVT. Fibrinolytic susceptibility was assayed by reacting plasma with thromboplastin and tissue plasminogen activator and recording a nephelometric signal. Coagulation time (CT), coagulum lysis time (CLT) and maximal increase in coagulum light scatter (CLS) were determined. Increase in D-dimer levels caused by coagulum lysis was also determined. This was viewed as a fibrinogen measure. CL T and CLS were interpreted as measures of fibrinolytic susceptibility and coagulum structure, respectively. CL T and CLS for patients and controls differed, p<0.025 and p<0.001, respectively. Compared to 5% for controls, 24% and 43% of the patients showed CL T and CLS outside the reference range. High fibrinogen levels could not explain the findings, since these were normal in most patients with abnormal CL T and CLS. Abnormal coagulum lysis and abnormal coagulum structure were thus found to be associated with DVT. Possible laboratory diagnostic role of CL T and CLS was investigated with bivariate reference ranges that excluded 5% and 0.3%. These ranges excluded significantly (p<0.0001) more patients, 47% and 27%, respectively. Tests for abnormal fibrinolytic susceptibility and coagulum structure may thus have a role in laboratory diagnosis of thrombotic disorders.

    Keywords
    Clot lysis, fibrin gel network, fibrinolysis, thrombosis
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-81002 (URN)
    Available from: 2012-09-05 Created: 2012-09-05 Last updated: 2012-09-05Bibliographically approved
    2. Blood plasma coagulation studied by surface plasmon resonance
    Open this publication in new window or tab >>Blood plasma coagulation studied by surface plasmon resonance
    Show others...
    2000 (English)In: Journal of Biomedical Optics, ISSN 1083-3668, E-ISSN 1560-2281, Vol. 5, no 1, p. 51-55Article in journal (Refereed) Published
    Abstract [en]

    A surface plasmon resonance (SPR) apparatus was used to investigate blood plasma coagulation in real time as a function of thromboplastin and heparin concentrations. The response curves were analyzed by curve fitting to a sigmoid curve equation, followed by extraction of the time constant. Clotting activation by thromboplastin resulted in increased time constant, as compared to spontaneously clotted plasma, in a dose dependent way. Addition of heparin to the thromboplastin-activated plasma counteracted this effect. Atomic force microscopy (AFM) pictures of sensor surfaces dried after completed clotting, revealed differences in fibrin network structures as a function of thromboplastin concentration, and the fiber thickness increased with decreased thromboplastin concentration. The physical reason for the SPR signal observed is ambiguous and is therefore discussed. However, the results summarized in the plots and the fibrin network properties observed by AFM correlate well with present common methods used to analyze blood coagulation.

    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-25064 (URN)10.1117/1.429968 (DOI)9493 (Local ID)9493 (Archive number)9493 (OAI)
    Available from: 2009-10-07 Created: 2009-10-07 Last updated: 2017-12-13Bibliographically approved
    3. Surface plasmon resonance (SPR) analysis of coagulation in whole blood with application in prothrombin time assay
    Open this publication in new window or tab >>Surface plasmon resonance (SPR) analysis of coagulation in whole blood with application in prothrombin time assay
    Show others...
    1999 (English)In: Biosensors & bioelectronics, ISSN 0956-5663, E-ISSN 1873-4235, Vol. 14, no 8-9, p. 671-682Article in journal (Refereed) Published
    Abstract [en]

    It is previously shown that surface plasmon resonance (SPR) can be used to study blood plasma coagulation. This work explores the use of this technique for the analysis of tissue factor induced coagulation, i.e. prothrombin time (PT) analysis, of whole blood and plasma. The reference method was nephelometry. The prothrombin time analysis by SPR was performed by mixing two volumes of blood/plasma, one volume of thromboplastin, and one volume of CaCl2 solution directly on a sensor surface. The measurements show good agreement between nephelometry and SPR plasma analysis and also between SPR plasma and whole blood analysis. The effect of anticoagulant treatment on the clotting times was significant both quantitatively and qualitatively. The impact on the SPR signal of different physiological events in the coagulation process is discussed, and tentative interpretations of the sensorgram features are given. The major advantage of the SPR method compared to nephelometry is the possibility to perform analysis on whole blood instead of plasma. In conclusion, SPR is a promising method for whole blood coagulation analysis.

    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-25062 (URN)10.1016/S0956-5663(99)00050-0 (DOI)9491 (Local ID)9491 (Archive number)9491 (OAI)
    Available from: 2009-10-07 Created: 2009-10-07 Last updated: 2017-12-13Bibliographically approved
    4. Comparison of surface plasmon resonance and quartz crystal microbalance in the study of whole blood and plasma coagulation
    Open this publication in new window or tab >>Comparison of surface plasmon resonance and quartz crystal microbalance in the study of whole blood and plasma coagulation
    Show others...
    2000 (English)In: Biosensors & bioelectronics, ISSN 0956-5663, E-ISSN 1873-4235, Vol. 15, no 11-12, p. 605-613Article in journal (Refereed) Published
    Abstract [en]

    The coagulation of blood plasma and whole blood was studied with a surface plasmon resonance (SPR) based device and a quartz crystal microbalance instrument with energy dissipation detection (QCM-D). The SPR and QCM-D response signals were similar in shape but differing in time scales, reflecting differences in detection mechanisms. The QCM-D response time was longer than SPR, as a physical coupling of the sample to the substrate is required for molecules to be detected by the QCM-method. Change of sample properties within the evanescent field is sufficient for detection with SPR. Both the SPR signals and the QCM-D frequency and dissipation shifts showed dependency on concentrations of coagulation activator and sensitivity to heparin additions. The ratio of dissipation to frequency shifts, commonly considered to reflect viscoelastic properties of the sample, varied with the concentration of activator in blood plasma but not in whole blood. Additions of heparin to the thromboplastin activated whole blood sample, however, made the ratio variation reoccur. Implications of these observations for the understanding of the blood coagulation processes as well as the potential of the two methods in the clinic and in research are discussed.

    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-25061 (URN)10.1016/S0956-5663(00)00125-1 (DOI)9490 (Local ID)9490 (Archive number)9490 (OAI)
    Available from: 2009-10-07 Created: 2009-10-07 Last updated: 2017-12-13Bibliographically approved
    5. Surface plasmon resonance and free oscillation rheometry in combination: A new approach forstudies on haemostasis and biomaterials
    Open this publication in new window or tab >>Surface plasmon resonance and free oscillation rheometry in combination: A new approach forstudies on haemostasis and biomaterials
    Show others...
    (English)Manuscript (preprint) (Other academic)
    Abstract [en]

    In haemostasis and biomaterial research it is important to be able to study biological processes at surfaces and in the bulk. Surface plasmon resonance (SPR) is sensitive to changes at surface and free oscillation rheometry (FOR) probes the bulk. The present work demonstrates the usefulness of the combination of the techniques for simultaneous real-time measurements on coagulation and fibrinolysis of blood plasma, as well as coagulation of whole blood. SFLLRN stimulated coagulation of native whole blood presented a higher SPR signal with a different appearance than for plasma coagulation, while the FOR signals corresponding to plasma and whole blood coagulation were similar. This result indicated that the SPR technique was more sensitive to cell-surface interactions than to fibrin formation in whole blood, while the FOR technique were equally sensitive to coagulation in whole blood and plasma. Spontaneous coagulation of native whole blood in contact with methyland hydroxyl-terminated self-assembled monolayers on gold and gold surfaces regenerated after coagulation by degradation of adsorbed proteins with trypsin and SOS were also studied. The regenerated gold surfaces displayed the shortest coagulation times, although the contact-activation of blood coagulation was found to be low. The methylated and hydroxylated surfaces were comparable in terms of coagulation activation, while the hydroxylated surfaces presented FOR signals that indicated difficulties for the coagulum to attach to the surface. The combination of SPR and FOR may be suited for studies of cell-surface interactions, and may find applications in studies of blood cell defects in patients and testing of medical substances.

    Keywords
    Surface plasmon resonance, free oscillation rheometry, whole blood coagulation, fibrinolysis
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-81014 (URN)
    Available from: 2012-09-05 Created: 2012-09-05 Last updated: 2012-09-05Bibliographically approved
    6. Comparative studies with surface plasmon resonance and free oscillation rheometry on the inhibition of platelets with cytochalasin E and monoclonal antibodies towards GPIIb/IIIa
    Open this publication in new window or tab >>Comparative studies with surface plasmon resonance and free oscillation rheometry on the inhibition of platelets with cytochalasin E and monoclonal antibodies towards GPIIb/IIIa
    Show others...
    2002 (English)In: Biosensors & bioelectronics, ISSN 0956-5663, E-ISSN 1873-4235, Vol. 17, no 9, p. 761-771Article in journal (Refereed) Published
    Abstract [en]

    In the haemostatic system a multitude of processes are intertwined in fine-tuned interactions that arrest bleeding, keep the circulatory system open, and the blood flowing. The occurrence of both surface and bulk interactions adds an additional dimension of complexity. These insights have led to the belief that global overall procedures can inform on the likely behaviour of the system in health and disease. Two sensing procedures: surface plasmon resonance (SPR), which senses surface interactions, and free oscillation rheometry (FOR), which senses interactions within the bulk, have been combined and evaluated. The contribution of blood cells, mainly platelets, to the SPR and FOR signals was explored by simultaneous SPR and FOR measurement during native whole blood coagulation, accelerated via the platelets through addition of SFLLRN peptide and inhibition of platelet aggregation with abciximab (ReoPro®) and of shape change with cytochalasin E. The SPR technique was found to be sensitive to inhibition of blood cell functions such as adhesion to and spreading on surfaces, as well as platelet aggregation. SPR seemed not to be directly sensitive to fibrin polymerisation in coagulating whole blood. The FOR technique detected the coagulation as a bulk phenomenon, i.e. the gelation of the blood due to fibrin formation was detected. The combination of SPR and FOR may therefore be suitable for studies on blood cell functions during coagulation.

    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-25066 (URN)10.1016/S0956-5663(02)00049-0 (DOI)9495 (Local ID)9495 (Archive number)9495 (OAI)
    Available from: 2009-10-07 Created: 2009-10-07 Last updated: 2017-12-13Bibliographically approved
  • 43.
    Hansson, Kenny M.
    et al.
    Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Lindahl, Tomas L.
    Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Rånby, Mats
    Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Abnormalities in coagulum lysis and structure are associated with deep venous thrombosisManuscript (preprint) (Other academic)
    Abstract [en]

    The present study aimed to investigate the relationship between deep venous thrombosis (DVT) and fibrinolytic susceptibility of plasma coagulum, including the possible role of this property in laboratory diagnosis. From 276 patients consecutively admitted to hospital for suspected deep venous thrombosis (DVT), 75 patients and 47 controls were selected. With certainty, the patients and controls either had or did not have DVT. Fibrinolytic susceptibility was assayed by reacting plasma with thromboplastin and tissue plasminogen activator and recording a nephelometric signal. Coagulation time (CT), coagulum lysis time (CLT) and maximal increase in coagulum light scatter (CLS) were determined. Increase in D-dimer levels caused by coagulum lysis was also determined. This was viewed as a fibrinogen measure. CL T and CLS were interpreted as measures of fibrinolytic susceptibility and coagulum structure, respectively. CL T and CLS for patients and controls differed, p<0.025 and p<0.001, respectively. Compared to 5% for controls, 24% and 43% of the patients showed CL T and CLS outside the reference range. High fibrinogen levels could not explain the findings, since these were normal in most patients with abnormal CL T and CLS. Abnormal coagulum lysis and abnormal coagulum structure were thus found to be associated with DVT. Possible laboratory diagnostic role of CL T and CLS was investigated with bivariate reference ranges that excluded 5% and 0.3%. These ranges excluded significantly (p<0.0001) more patients, 47% and 27%, respectively. Tests for abnormal fibrinolytic susceptibility and coagulum structure may thus have a role in laboratory diagnosis of thrombotic disorders.

  • 44.
    Hansson, Kenny M.
    et al.
    Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Tengvall, Pentti
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, The Institute of Technology.
    Lundström, Ingemar
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, The Institute of Technology.
    Rånby, Mats
    Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Lindahl, Tomas L.
    Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Surface plasmon resonance and free oscillation rheometry in combination: A new approach forstudies on haemostasis and biomaterialsManuscript (preprint) (Other academic)
    Abstract [en]

    In haemostasis and biomaterial research it is important to be able to study biological processes at surfaces and in the bulk. Surface plasmon resonance (SPR) is sensitive to changes at surface and free oscillation rheometry (FOR) probes the bulk. The present work demonstrates the usefulness of the combination of the techniques for simultaneous real-time measurements on coagulation and fibrinolysis of blood plasma, as well as coagulation of whole blood. SFLLRN stimulated coagulation of native whole blood presented a higher SPR signal with a different appearance than for plasma coagulation, while the FOR signals corresponding to plasma and whole blood coagulation were similar. This result indicated that the SPR technique was more sensitive to cell-surface interactions than to fibrin formation in whole blood, while the FOR technique were equally sensitive to coagulation in whole blood and plasma. Spontaneous coagulation of native whole blood in contact with methyland hydroxyl-terminated self-assembled monolayers on gold and gold surfaces regenerated after coagulation by degradation of adsorbed proteins with trypsin and SOS were also studied. The regenerated gold surfaces displayed the shortest coagulation times, although the contact-activation of blood coagulation was found to be low. The methylated and hydroxylated surfaces were comparable in terms of coagulation activation, while the hydroxylated surfaces presented FOR signals that indicated difficulties for the coagulum to attach to the surface. The combination of SPR and FOR may be suited for studies of cell-surface interactions, and may find applications in studies of blood cell defects in patients and testing of medical substances.

  • 45.
    Hansson, Kenny
    et al.
    Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Tengvall, Pentti
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, The Institute of Technology.
    Lundström, Ingemar
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, The Institute of Technology.
    Rånby, Mats
    Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Lindahl, Tomas
    Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Comparative studies with surface plasmon resonance and free oscillation rheometry on the inhibition of platelets with cytochalasin E and monoclonal antibodies towards GPIIb/IIIa2002In: Biosensors & bioelectronics, ISSN 0956-5663, E-ISSN 1873-4235, Vol. 17, no 9, p. 761-771Article in journal (Refereed)
    Abstract [en]

    In the haemostatic system a multitude of processes are intertwined in fine-tuned interactions that arrest bleeding, keep the circulatory system open, and the blood flowing. The occurrence of both surface and bulk interactions adds an additional dimension of complexity. These insights have led to the belief that global overall procedures can inform on the likely behaviour of the system in health and disease. Two sensing procedures: surface plasmon resonance (SPR), which senses surface interactions, and free oscillation rheometry (FOR), which senses interactions within the bulk, have been combined and evaluated. The contribution of blood cells, mainly platelets, to the SPR and FOR signals was explored by simultaneous SPR and FOR measurement during native whole blood coagulation, accelerated via the platelets through addition of SFLLRN peptide and inhibition of platelet aggregation with abciximab (ReoPro®) and of shape change with cytochalasin E. The SPR technique was found to be sensitive to inhibition of blood cell functions such as adhesion to and spreading on surfaces, as well as platelet aggregation. SPR seemed not to be directly sensitive to fibrin polymerisation in coagulating whole blood. The FOR technique detected the coagulation as a bulk phenomenon, i.e. the gelation of the blood due to fibrin formation was detected. The combination of SPR and FOR may therefore be suitable for studies on blood cell functions during coagulation.

  • 46.
    Hansson, Kenny
    et al.
    Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Tengvall, Pentti
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, The Institute of Technology.
    Lundström, Ingemar
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, The Institute of Technology.
    Rånby, Mats
    Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Lindahl, Tomas
    Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Surface plasmon resonance and free oscillation rheometry in combination: a useful approach for studies on haemostasis and interactions between whole blood and artificial surfaces2002In: Biosensors & bioelectronics, ISSN 0956-5663, E-ISSN 1873-4235, Vol. 17, no 9, p. 747-759Article in journal (Refereed)
    Abstract [en]

    In haemostatic and biomaterial research biological processes at surfaces and in the bulk phase of the surface-contacting medium are important. The present work demonstrates the usefulness of the combination of surface plasmon resonance (SPR), sensitive to changes in refractive index at surfaces, and free oscillation rheometry (FOR), sensitive to rheological properties of the bulk, for simultaneous real-time measurements on coagulation and fibrinolysis of blood plasma and coagulation of whole blood. SFLLRN stimulated coagulation of native whole blood presented a higher SPR signal with different appearance than plasma coagulation, while the FOR signals corresponding to plasma and whole blood coagulation were similar. This indicated that the SPR technique was more sensitive to cell-surface interactions than to fibrin formation in whole blood during coagulation, while the FOR technique were equally sensitive to coagulation in whole blood and plasma. Spontaneous coagulation of native whole blood in contact with methyl- and hydroxyl-terminated self-assembled monolayers (SAM) on gold and gold surfaces regenerated after coagulation were also studied. The regenerated gold surfaces displayed the shortest coagulation times, although the contact-activation of blood coagulation for these surfaces was low. The methylated and hydroxylated surfaces were comparable in terms of coagulation activation, while the hydroxylated surfaces presented FOR signals that indicated detaching of the coagulum from the surface. The combination of SPR and FOR is well suited for studies of cell– and protein–surface interactions and simultaneous bulk processes. Possible applications are investigations of blood cell defects in patients and monitoring of native whole blood interactions with artificial surfaces.

  • 47.
    Hansson, Kenny
    et al.
    Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Vikinge, T. P.
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, Faculty of Health Sciences.
    Rånby, M.
    Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Tengvall, Pentti
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, The Institute of Technology.
    Lundström, Ingemar
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, The Institute of Technology.
    Johansen, Knut
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, Faculty of Health Sciences.
    Lindahl, Tomas
    Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Surface plasmon resonance (SPR) analysis of coagulation in whole blood with application in prothrombin time assay1999In: Biosensors & bioelectronics, ISSN 0956-5663, E-ISSN 1873-4235, Vol. 14, no 8-9, p. 671-682Article in journal (Refereed)
    Abstract [en]

    It is previously shown that surface plasmon resonance (SPR) can be used to study blood plasma coagulation. This work explores the use of this technique for the analysis of tissue factor induced coagulation, i.e. prothrombin time (PT) analysis, of whole blood and plasma. The reference method was nephelometry. The prothrombin time analysis by SPR was performed by mixing two volumes of blood/plasma, one volume of thromboplastin, and one volume of CaCl2 solution directly on a sensor surface. The measurements show good agreement between nephelometry and SPR plasma analysis and also between SPR plasma and whole blood analysis. The effect of anticoagulant treatment on the clotting times was significant both quantitatively and qualitatively. The impact on the SPR signal of different physiological events in the coagulation process is discussed, and tentative interpretations of the sensorgram features are given. The major advantage of the SPR method compared to nephelometry is the possibility to perform analysis on whole blood instead of plasma. In conclusion, SPR is a promising method for whole blood coagulation analysis.

  • 48.
    Hedlund, Maria
    et al.
    Department of Laboratory Medicine, Division of Microbiology, Immunology and Glycobiologi, Lund University, Lund, Sweden.
    Bengtson, Per
    Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Påhlsson, Peter
    Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Leffler, Hakon
    Department of Laboratory Medicine, Division of Microbiology, Immunology and Glycobiologi, Lund University, Lund, Sweden.
    Galectin mediated tethering and arrest of neutrophils under shear flow conditionsManuscript (preprint) (Other academic)
    Abstract [en]

    According to the conventional wisdom leukocyte recruitment to an inflammatory site is initiated by selectin mediated capture and rolling along the activated endothelium. The galectins are members of another family oflectins with affinity for ß-galactosides. Expressed on endothelial cells, galectin-1 and galectin-3 have been proposed to mediate cell-cell interactions during inflammation and tumor cell metastasis, and hence act as an alternative to selectins/integrins under certain circumstances. To begin testing this hypothesis, we examined the interaction of neutrophils -with a galectin-1 or galectin-3 coated surface under shear flow conditions. Both galectins were found to trigger neutrophil arrest in a dose and carbohydrate dependent manner at coating concentrations of ≥ 200 nM, and 1 dynes/cm2 wall shear stress. While, galectin-3 mediated neutrophil arrest was immediate, galectin-1 triggered a brief period of tethering before arrest. Rapidly following arrest neutrophils spread onto the galectin-coated surface. Cell spreading was accompanied by a redistribution of actin filaments, from an initial even staining with FITC-phalloidin to a more peripheral distribution in spread cells. These data suggest that galectin-1 and galectin-3 may act as adhesion molecules capturing and arresting neutrophils at sites knovvn to be less dependent on selectins and ß2integrins. They behave in part like selectins in capturing the neutrophils, but also like the integrins in triggering firm adhesion and cell spreading.

  • 49. Helander, A
    et al.
    Jones, A Wayne
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry.
    5-HTOL - ny biokemisk alkoholmarkör med rättsmedicinska tillämpningar2002In: Läkartidningen, ISSN 0023-7205, E-ISSN 1652-7518, Vol. 99, p. 3950-3954Article in journal (Other academic)
  • 50. Hillarp, Andreas
    et al.
    Egberg, Nils
    Fagerberg, Inger
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Östergötlands Läns Landsting, Centre for Laboratory Medicine, Department of Clinical Chemistry.
    Lindahl, Tomas
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Östergötlands Läns Landsting, Centre for Laboratory Medicine, Department of Clinical Chemistry.
    Nordin, Gunnar
    Stigendal, Lennart
    Mer samstämmiga laboratorieresultat efter övergången till INR. Skillnaderna mellan sjukhus- och primärvårdslaboratorier utjämnade.2002In: Läkartidningen, ISSN 0023-7205, E-ISSN 1652-7518, Vol. 99, p. 5068-5074Article in journal (Other academic)
12345 1 - 50 of 211
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