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Salerud, Göran
Alternative names
Publications (10 of 129) Show all publications
Latorre, M., Salerud, G. & Wårdell, K. (2016). Describing Measurement Behaviour of a Surface Ag-AgCl Electrode Using the Paxon Test Platform. In: XIV MEDITERRANEAN CONFERENCE ON MEDICAL AND BIOLOGICAL ENGINEERING AND COMPUTING 2016: . Paper presented at 14th Mediterranean Conference on Medical and Biological Engineering and Computing (MEDICON) (pp. 442-445). SPRINGER, 57.
Open this publication in new window or tab >>Describing Measurement Behaviour of a Surface Ag-AgCl Electrode Using the Paxon Test Platform
2016 (English)In: XIV MEDITERRANEAN CONFERENCE ON MEDICAL AND BIOLOGICAL ENGINEERING AND COMPUTING 2016, SPRINGER , 2016, Vol. 57, 442-445 p.Conference paper, Published paper (Refereed)
Abstract [en]

A better understanding of bioelectrodes can be acquired with extended testing, which will lead to better methodology and data quality. Today electrodes are evaluated for intraelectrode differences and performance with a traditional gain-phase method, while using the physical axon action potential generator (Paxon) test platform offers extended test possibilities. The direct gain-phase measurements are useful to extract the transfer function of the electrode, as well as some other base parameters. The Paxon test platform is a complementary method that tests electrodes under conditions that are more realistic, mimicking real measurement situations in comparison to the gain-phase method. The Paxon also allows tests to be performed beyond what the gain-phase methods can measure, for example electrode rotation, which would uncover variations in the symmetry of the electrode. When tested, the symmetry properties of the electrode, where the electrodes are rotated in steps of 90 degrees, resulted in a peak to peak variation in detected amplitude of 5.3 +/- 8.9 mV. Therefore, the Paxon appears to be a feasible test platform for characterizing electrodes beyond the gain-phase tests in a semiautomatic manner.

Place, publisher, year, edition, pages
SPRINGER, 2016
Series
IFMBE Proceedings, ISSN 1680-0737
Keyword
Electrode testing; Characterization; Coupling Parameters; Stability test; Axon potential
National Category
Medical Equipment Engineering
Identifiers
urn:nbn:se:liu:diva-129510 (URN)10.1007/978-3-319-32703-7_86 (DOI)000376283000086 ()978-3-319-32703-7 (ISBN)978-3-319-32701-3 (ISBN)
Conference
14th Mediterranean Conference on Medical and Biological Engineering and Computing (MEDICON)
Available from: 2016-06-20 Created: 2016-06-20 Last updated: 2017-06-19Bibliographically approved
Fredly, S., Fugelseth, D., Nygaard, C. S., Salerud, G., Stiris, T. & Kvernebo, K. (2016). Noninvasive assessments of oxygen delivery from the microcirculation to skin in hypothermia-treated asphyxiated newborn infants. Pediatric Research, 76(6), 902-906.
Open this publication in new window or tab >>Noninvasive assessments of oxygen delivery from the microcirculation to skin in hypothermia-treated asphyxiated newborn infants
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2016 (English)In: Pediatric Research, ISSN 0031-3998, E-ISSN 1530-0447, Vol. 76, no 6, 902-906 p.Article in journal (Refereed) Published
Abstract [en]

BACKGROUND:

Therapeutic hypothermia (TH) has become standard treatment for severe and moderate hypoxic-ischemic neonatal encephalopathy (HIE). Our group has developed an optically based, noninvasive concept of assessing the capacity for oxygen delivery from the microcirculation to the cells of a tissue under investigation. The hypothesis was that mechanisms of reduced oxygen delivery due to reduced metabolism in cooled asphyxiated neonates could be characterized with this concept.

METHODS:

The skin of 28 asphyxiated newborn infants was studied on days 1 and 3 during TH and on day 4 following rewarming with laser Doppler perfusion measurements (LDPM), computer-assisted video microscopy (CAVM), and diffuse reflectance spectroscopy (DRS). Twenty-five healthy neonates served as a control group.

RESULTS:

The LDPM decreased during cooling (P < 0.01). Functional capillary density was higher both during and following TH compared with control infants (P < 0.01). Capillary flow velocities were reduced during TH (P < 0.05). The heterogeneity of the flow velocities was larger in the HIE infants than in the control infants. Tissue oxygen extraction was higher during TH (P < 0.01).

CONCLUSION:

This study indicates that assessments of skin microvascular density, capillary flow velocity, and oxygen extraction can be used to characterize reduced oxygen delivery to cells during TH

National Category
Physiology
Identifiers
urn:nbn:se:liu:diva-128796 (URN)10.1038/pr.2016.16 (DOI)000377481100013 ()26854800 (PubMedID)
Note

Clinical Investigation

Available from: 2016-05-31 Created: 2016-05-31 Last updated: 2018-01-10
Latorre, M. A., Salerud, E. G. & Wårdell, K. (2015). Characterization of a Surface Ag-AgCl Electrode using the Paxon Test Platform. .
Open this publication in new window or tab >>Characterization of a Surface Ag-AgCl Electrode using the Paxon Test Platform
2015 (English)Manuscript (preprint) (Other academic)
Abstract [en]

Evaluation of an electrode for intraelectrode differences using both a traditional gain-phase method and the Paxon test platform. The direct gain-phase measurements are useful to extract the transfer function of the electrode, as well as some other base parameters. The Paxon test platform is a complementary method that tests electrodes under conditions that are more realistic than the gel-to-gel connection used in the gain-phase method. Testing stability over time e.g. DC signal drift (worst set 6,31 ± 43,00 nV) over a one hour of measurement duration was carried out. The Paxon also lets tests be performed beyond what the gain-phase methods can measure, for example electrode rotation, which would uncover variations in the symmetry of the electrode. When tested, the symmetry properties of the electrode (test set variations, start to end, over rotations 0,90,180 and 270 degrees) resulted in a peak to peak variation in detected amplitude of 5.3 ±8.9 mV. Intraelectrode variations were detected and quantized with the Paxon test platform.

Keyword
Electrode testing, Characterization, Coupling Parameters. Stability test, Axon potential
National Category
Medical Engineering
Identifiers
urn:nbn:se:liu:diva-121087 (URN)
Available from: 2015-09-07 Created: 2015-09-07 Last updated: 2017-02-03Bibliographically approved
Ewerlöf, M., Salerud, E. G., Strömberg, T. & Larsson, M. (2015). Estimating skin blood saturation by selecting a subset of hyperspectral imaging data. In: Daniel L. Farkas; Dan V. Nicolau; Robert C. Leif (Ed.), Imaging, Manipulation, and Analysis of Biomolecules, Cells, and Tissues XIII: . Paper presented at SPIE Photonics West BIOS. SPIE, 9328.
Open this publication in new window or tab >>Estimating skin blood saturation by selecting a subset of hyperspectral imaging data
2015 (English)In: Imaging, Manipulation, and Analysis of Biomolecules, Cells, and Tissues XIII / [ed] Daniel L. Farkas; Dan V. Nicolau; Robert C. Leif, SPIE, 2015, Vol. 9328Conference paper, Published paper (Refereed)
Abstract [en]

Skin blood haemoglobin saturation (𝑠b) can be estimated with hyperspectral imaging using the wavelength (λ) range of 450-700 nm where haemoglobin absorption displays distinct spectral characteristics. Depending on the image size and photon transport algorithm, computations may be demanding. Therefore, this work aims to evaluate subsets with a reduced number of wavelengths for 𝑠b estimation. White Monte Carlo simulations are performed using a two-layered tissue model with discrete values for epidermal thickness (𝑇epi) and the reduced scattering coefficient (μ's ), mimicking an imaging setup. A detected intensity look-up table is calculated for a range of model parameter values relevant to human skin, adding absorption effects in the post-processing. Skin model parameters, including absorbers, are; μ's (λ), 𝑇epi, haemoglobin saturation (𝑠b), tissue fraction blood (𝑐b) and tissue fraction melanin (𝑐mel). The skin model paired with the look-up table allow spectra to be calculated swiftly. Three inverse models with varying number of free parameters are evaluated: A(𝑠b, 𝑐b), B(𝑠b, 𝑐b, 𝑐mel) and C(all parameters free). Fourteen wavelength candidates are selected by analysing the maximal spectral sensitivity to 𝑠b and minimizing the sensitivity to 𝑐b. All possible combinations of these candidates with three, four and 14 wavelengths, as well as the full spectral range, are evaluated for estimating 𝑠b for 1000 randomly generated evaluation spectra. The results show that the simplified models A and B estimated 𝑠b accurately using four wavelengths (mean error 2.2% for model B). If the number of wavelengths increased, the model complexity needed to be increased to avoid poor estimations.

Place, publisher, year, edition, pages
SPIE: , 2015
Series
Proceedings of SPIE, ISSN 0277-786X ; 9328
Keyword
Hyper spectral imaging, Blood, Skin, Tissues, Absorption, Displays, Photon transport, Scattering, Simulations
National Category
Medical Laboratory and Measurements Technologies
Identifiers
urn:nbn:se:liu:diva-116478 (URN)10.1117/12.2075292 (DOI)000354105000013 ()978-1-62841-418-9 (ISBN)
Conference
SPIE Photonics West BIOS
Available from: 2015-03-27 Created: 2015-03-27 Last updated: 2016-08-31Bibliographically approved
Kozak Ljunggren, M., Elizondo, R. A., Edin, J., Olsen, D., Merrett, K., Lee, C.-J., . . . Griffith, M. (2014). Effect of Surgical Technique on Corneal Implant Performance. Translational Vision Science & Technology, 3(2), 1-13.
Open this publication in new window or tab >>Effect of Surgical Technique on Corneal Implant Performance
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2014 (English)In: Translational Vision Science & Technology, ISSN 2164-2591, Vol. 3, no 2, 1-13 p.Article in journal (Refereed) Published
Abstract [en]

Purpose: Our aim was to determine the effect of a surgical technique on biomaterial implant performance, specifically graft retention.

 

Methods: Twelve mini pigs were implanted with cell-free, 1-ethyl-3-(3-dimethyl aminopropyl) carbodiimide (EDC)/N-hydroxysuccinimide (NHS) cross-linked recombinant human collagen type III (RHCIII) hydrogels as substitutes for donor corneal allografts using overlying sutures with or without human amniotic membrane (HAM) versus interrupted sutures with HAM. The effects of the retention method were compared as well as the effects of collagen concentration (13.7% to 15% RHCIII).

Results: All implanted corneas showed initial haze that cleared with time, resulting in corneas with optical clarity matching those of untreated controls. Biochemical analysis showed that by 12 months post operation, the initial RHCIII implants had been completely remodeled, as type I collagen, was the major collagenous protein detected, whereas no RHCIII could be detected. Histological analysis showed all implanted corneas exhibited regeneration of epithelial and stromal layers as well as nerves, along with touch sensitivity and tear production. Most neovascularization was seen in corneas stabilized by interrupted sutures.

Conclusions: This showed that the surgical technique used does have a significant effect on the overall performance of corneal implants, overlying sutures caused less vascularization than interrupted sutures.

Translational Relevance: Understanding the significance of the suturing technique can aid the selection of the most appropriate procedure when implanting artificial corneal substitutes. The same degree of regeneration, despite a higher collagen content indicates that future material development can progress toward stronger, more resistant implants.

Place, publisher, year, edition, pages
Association for Research in Vision and Ophthalmology, 2014
Keyword
biosynthetic cornea; corneal regeneration; biomaterials; recombinant human collagen; corneal transplantation
National Category
Medical and Health Sciences Biomaterials Science Ophthalmology
Identifiers
urn:nbn:se:liu:diva-108585 (URN)10.1167/tvst.3.2.6 (DOI)24749003 (PubMedID)
Available from: 2014-06-30 Created: 2014-06-30 Last updated: 2015-08-10Bibliographically approved
Strömberg, T., Larsson, M., Salerud, G. & Wårdell, K. (2014). Laser Doppler Perfusion Monitoring and Imaging.. In: Biomedical Photonics Handbook: . CRC Press.
Open this publication in new window or tab >>Laser Doppler Perfusion Monitoring and Imaging.
2014 (English)In: Biomedical Photonics Handbook, CRC Press, 2014Chapter in book (Refereed)
Place, publisher, year, edition, pages
CRC Press, 2014
Keyword
Biomedical optics, microcirculation
National Category
Medical Engineering
Identifiers
urn:nbn:se:liu:diva-108586 (URN)0-8493-1116-0 (ISBN)
Available from: 2014-06-30 Created: 2014-06-30 Last updated: 2017-02-03Bibliographically approved
Wester, T., Ahmed Awan, Z., Skylstad Kvernebo, T., Salerud, G. & Kvernebo, K. (2014). Skin microvascular morphology and hemodynamics during treatment with veno-arterial extra-corporeal membrane oxygenation. Clinical hemorheology and microcirculation, 56(2), 119-131.
Open this publication in new window or tab >>Skin microvascular morphology and hemodynamics during treatment with veno-arterial extra-corporeal membrane oxygenation
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2014 (English)In: Clinical hemorheology and microcirculation, ISSN 1386-0291, E-ISSN 1875-8622, Vol. 56, no 2, 119-131 p.Article in journal (Refereed) Published
Abstract [en]

Objectives: To explore the potentials of microcirculatory assessments for predicting outcome of patients treated with extra corporeal membrane oxygenation for cardiogenic shock. Methods: Eight patients with acute cardiogenic shock treated with ECMO and eight healthy controls were examined with skin vital microscopy and laser Doppler perfusion measurements. Results: Three patients died on ECMO (group 1). Five patients were successfully weaned off ECMO (group 2). Four patients were discharged from hospital and one died after successful weaning from bleeding complications. Patients surviving ECMO (group 2) had microcirculatory findings comparable with healthy controls. Patients in group 1 showed major skin microvascular pathology: pericapillary bleedings (n = 1), pericapillary dark haloes (n = 2) and capillary micro thrombi (n = 1). As compared with survivors they had lower functional capillary density (FCD) (n = 3), higher heterogeneity of functional capillary density (n = 3) and significantly reduced capillary mean flow-categorical velocity (n = 2). Laser Doppler measurements in group 1 had non-significant lower laser Doppler flux values as compared with survivors and controls. Conclusion: Skin microvascular pathology as detected with video microscopy (pericapillary bleedings or haloes, micro-thrombi/capillaries with “no flow”, low FCD with high spatial distribution heterogeneity or low mean flow-categorial velocity seems to be associated with poor prognosis.

Place, publisher, year, edition, pages
IOS Press, 2014
Keyword
Capillary flow heterogeneity, capillary pathology, cardiogenic shock, extra-corporeal life support, extra-corporeal membrane oxygenation, microvascular hemodynamics, microvascular monitoring, vital microscopy
National Category
Medical and Health Sciences
Identifiers
urn:nbn:se:liu:diva-93305 (URN)10.3233/CH-131670 (DOI)000333079700004 ()23357861 (PubMedID)
Available from: 2013-05-30 Created: 2013-05-30 Last updated: 2017-12-06
Benosman, M., Bereksi-reguig, F. & Salerud, G. (2013). Analysis of ECG-trunk muscle signal amplitude and heart rate relationship. Journal of Medical Engineering & Technology, 37(7), 449-455.
Open this publication in new window or tab >>Analysis of ECG-trunk muscle signal amplitude and heart rate relationship
2013 (English)In: Journal of Medical Engineering & Technology, ISSN 0309-1902, E-ISSN 1464-522X, Vol. 37, no 7, 449-455 p.Article in journal (Refereed) Published
Abstract [en]

The objective of this paper is to investigate if bioelectrical signals, generated from trunk muscles identified in an electrocardiogram (ECG) signal presented in this paper as ECG-Trunk Muscles Signals amplitude (Ecg-TMSA) are correlated with Heart rate (HR) during different levels of physical activity and also if Ecg-TMSA is not influenced by mental activity. HR and Ecg-TMSA were derived from ECG in 14 subjects when walking and jogging at different treadmill velocities from 4–10 (km h−1). The mean relationship for all 14 subjects was HR = (42.3 ± 0.2) + (45.3 ± 2.8) Ecg-TMSA, r2 = 0.91. The result of one individual data points example for a 21 min experiment was (r2 = 0.93, p < 0.0001, n = 336). The obtained results show a linear relationship between Ecg-TMSA and HR. Moreover, the Ecg-TMSA was not affected by mental activity

Place, publisher, year, edition, pages
Informa Healthcare, 2013
Keyword
ECG noise, heart rate, mental activity, physical activity, trunk muscles bio-signals
National Category
Medical Engineering
Identifiers
urn:nbn:se:liu:diva-108584 (URN)10.3109/03091902.2013.828107 (DOI)
Available from: 2014-06-30 Created: 2014-06-30 Last updated: 2017-12-05Bibliographically approved
Fredly, S., Kvernebo, K. & Salerud, G. (2013). Biophotonic Assessment of Microcirculation in Healthy Newborn Children. In: : . Paper presented at 1st International Conference "Biophotonics - Riga 2013", 26-31 August 2013, Riga, Latvia. .
Open this publication in new window or tab >>Biophotonic Assessment of Microcirculation in Healthy Newborn Children
2013 (English)Conference paper, Oral presentation with published abstract (Other academic)
National Category
Medical Engineering
Identifiers
urn:nbn:se:liu:diva-108587 (URN)
Conference
1st International Conference "Biophotonics - Riga 2013", 26-31 August 2013, Riga, Latvia
Available from: 2014-06-30 Created: 2014-06-30 Last updated: 2014-08-29
Benosman, M., Bereksi-reguig, F. & Salerud, G. (2012). Distingush physical activity from mental stress analyzing ECG signals with overlayed non cardiac muscle activity. In: BIOMEIC'12: . Paper presented at Biomedical Engineering International Conference (BIOMEIC'12), 10-11 October, Tlemcen, Algeria. .
Open this publication in new window or tab >>Distingush physical activity from mental stress analyzing ECG signals with overlayed non cardiac muscle activity
2012 (English)In: BIOMEIC'12, 2012Conference paper, Published paper (Other academic)
Keyword
heart rate, mental stress, physical activity, ECG signal, non-cardiac muscle acitivity
National Category
Medical Engineering
Identifiers
urn:nbn:se:liu:diva-93297 (URN)
Conference
Biomedical Engineering International Conference (BIOMEIC'12), 10-11 October, Tlemcen, Algeria
Available from: 2013-05-30 Created: 2013-05-30 Last updated: 2013-06-10
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