Tissue-nonspecific alkaline phosphatase (TNALP) is a glycoprotein expressed by osteoblasts that promotes bone mineralization. TNALP catalyzes the hydrolysis of the mineralization inhibitor inorganic pyrophosphate and ATP to provide inorganic phosphate, thus controlling the inorganic pyrophosphate/inorganic phosphate ratio to enable the growth of hydroxyapatite crystals. N-linked glycosylation of TNALP is essential for protein stability and enzymatic activity and is responsible for the presence of different bone isoforms of TNALP associated with functional and clinical differences. The site-specific glycosylation profiles of TNALP are, however, elusive. TNALP has 5 potential N-glycosylation sites located at the asparagine (N) residues 140, 230, 271, 303, and 430. The objective of this study was to reveal the presence and structure of site-specific glycosylation in TNALP expressed in osteoblasts. Calvarial osteoblasts derived from Alpl^+/− expressing SV40 Large T antigen were transfected with soluble epitope-tagged human TNALP. Purified TNALP was analyzed with a lectin microarray, matrix-assisted laser desorption/ionization-time of flight mass spectrometry, and liquid chromatography with tandem mass spectrometry. The results showed that all sites (n = 5) were fully occupied predominantly with complex-type N-glycans. High abundance of galactosylated biantennary N-glycans with various degrees of sialylation was observed on all sites, as well as glycans with no terminal galactose and sialic acid. Furthermore, all sites had core fucosylation except site N271. Modelling of TNALP, with the protein structure prediction software ColabFold, showed possible steric hindrance by the adjacent side chain of W270, which could explain the absence of core fucosylation at N271. These novel findings provide evidence for N-linked glycosylation on all 5 sites of TNALP, as well as core fucosylation on 4 out of 5 sites. We anticipate that this new knowledge can aid in the development of functional and clinical assays specific for the TNALP bone isoforms.

ontext: Anemia and decreasing levels of hemoglobin (Hb) have previously been linked to increased fracture risk, but the added value to FRAX, the most utilized fracture prediction tool worldwide, is unknown.

Objective: To investigate the association between anemia, Hb levels, bone microstructure, and risk of incident fracture and to evaluate whether Hb levels improve fracture risk prediction in addition to FRAX clinical risk factors (CRFs).

Methods: A total of 2778 community-dwelling women, aged 75-80 years, and part of a prospective population-based cohort study in Sweden were included. At baseline, information on anthropometrics, CRFs, and falls was gathered, blood samples were collected, and skeletal characteristics were investigated using dual-energy x-ray absorptiometry and high-resolution peripheral quantitative computed tomography. At the end of follow-up, incident fractures were retrieved from a regional x-ray archive.

Results: The median follow-up time was 6.4 years. Low Hb was associated with worse total hip and femoral neck bone mineral density (BMD), and lower tibia cortical and total volumetric BMD, and anemia was associated with increased risk of major osteoporotic fracture (MOF; hazard ratio 2.04; 95% CI 1.58-2.64). Similar results were obtained for hip fracture and any fracture, also when adjusting for CRFs. The ratio between 10-year fracture probabilities of MOF assessed in models with Hb levels included and not included ranged from 1.2 to 0.7 at the 10th and 90th percentile of Hb, respectively.

Conclusion: Anemia and decreasing levels of Hb are associated with lower cortical BMD and incident fracture in older women. Considering Hb levels may improve the clinical evaluation of patients with osteoporosis and the assessment of fracture risk.

Aim To determine whether adolescents born before 28 gestational weeks have an increased risk for renal impairment. Methods Swedish infants, born before 28 gestational weeks in 2001 and 2002, were identified from a local register. A total of 16 children, 12 females and 4 males, were examined at 16-17 years of age with Cr-51-EDTA clearance. A comparison group (n = 26) was used. Results Most study participants (n = 13) had normal blood pressure; one individual had hypertension stage 1. All study participants had results within the reference interval for ionised calcium, parathyroid hormone, intact fibroblast growth factor-23 and for urinary albumin-to-creatinine ratio. Four out of 16 participants (25%) had a Cr-51-EDTA clearance less than 90 ml/min/1.73 m(2), indicating a reduced kidney function. Measured Cr-51-EDTA clearance values were significantly lower in the study group than in the comparison group (p = 0.0012). Five study participants (31%) were referred for further investigations. Conclusion Swedish children born before 28 gestational weeks have an increased risk of renal impairment later in life, suggesting that the kidney function in these individuals should be assessed, at least once, during adolescence.

The timed up and go (TUG) test measures physical performance and predicts falls in the elderly. In older women, TUG time predicts the risk of major osteoporotic fracture and hip fracture independently of clinical risk factors and bone mineral density, and has a substantial impact on fracture probabilities. Introduction The timed up and go (TUG) test measures physical performance and predicts falls in the elderly. A slow TUG has been associated with an increased fracture risk, but it is unclear whether the association is independent of clinical risk factors and bone mineral density (BMD). The aim of this study was to investigate if TUG time was associated with fracture risk independently of clinical risk factors and BMD and to determine its impact on fracture probabilities in older women. Methods A standardized questionnaire was used to assess information regarding clinical risk factors in the large population-based SUPERB study of 3028 older women (75-80 years). At baseline, the TUG test was performed and BMD measured with DXA. The association between TUG time and the risk of hip fracture and major osteoporotic fracture (MOF) was examined using an extension of Poisson regression. Results Fracture incidence increased steeply with increasing TUG time up to 12 s and subsequently started to level off. A slow TUG time was therefore defined as TUG > 12 s, a cutoff level then used in Cox models to study the association between slow TUG and fracture risk. A slow TUG time was associated with an increased risk of fracture (MOF 2.39 [1.80-3.18] and hip fracture 2.96 [1.62-5.40]). These associations were slightly attenuated but remained significant after adjustment for clinical risk factors and femoral neck BMD. Depending on BMD, the 4-year fracture probability of MOF increased by a factor of 1.5-1.9 in a 75-year-old woman with slow TUG (> 12 s). Conclusion The TUG time predicts the risk of MOF and hip fracture independently of clinical risk factors and BMD and has a substantial impact on fracture probabilities, indicating that inclusion of the TUG test in patient evaluation should be considered in order to improve fracture prediction in older women.

Because prevalent vertebral fracture (VF) is a strong predictor of future fractures, they are important to identify in clinical practice as osteoporosis medications are effective and can be used to reduce fracture risk in postmenopausal women with VF. Lateral spine imaging (LSI) with dual-energy X-ray absorptiometry (DXA) can be used to diagnose VFs accurately but is not widespread in clinical practice. The prognostic value of grade 1 (20% to 25% compression) VFs diagnosed by LSI with DXA has been insufficiently studied. The aim of this study was to determine if grade 1 VF is associated with incident fracture in older women. Sahlgrenska University Hospital Prospective Evaluation of Risk of Bone Fractures (SUPERB) is a population-based study of 3028 older women from Gothenburg, Sweden. Included women were 75 to 80 years of age at baseline, answered questionnaires, and were scanned with DXA (Discovery A, Hologic, Waltham, MA, USA). LSI was used to diagnose VFs, which were classified using the Genant semiquantitative method. Cox regression models were used to estimate the association between VFs at baseline and X-ray-verified incident fractures, with adjustment for confounders. Women with a grade 1 VF (n = 264) or a grade 2-3 VF (n = 349) were compared with women without any fracture (n = 1482). During 3.6 years (median, interquartile range [IQR] 1.5 years) of follow-up, 260 women had any incident fracture and 213 a major osteoporotic fracture (MOF). Women with only grade 1 VF had increased risk of any fracture (hazard ratio [HR] = 1.67; 95% confidence interval [CI] 1.18-2.36) and MOF (HR = 1.86; 95% CI 1.28-2.72). For MOF, this association remained after adjustment for clinical risk factors and femoral neck bone mineral density (BMD). In conclusion, grade 1 VFs were associated with incident MOF, also after adjustment for clinical risk factors and BMD, indicating that all VF identified by DXA should be considered in the evaluation of fracture risk in older women. © 2020 The Authors. Journal of Bone and Mineral Research published by American Society for Bone and Mineral Research..

PURPOSE OF REVIEW: In chronic kidney disease (CKD), disturbance of several metabolic regulatory mechanisms cause premature ageing, accelerated cardiovascular disease (CVD), and mortality. Single-target interventions have repeatedly failed to improve the prognosis for CKD patients. Epigenetic interventions have the potential to modulate several pathogenetic processes simultaneously. Alkaline phosphatase (ALP) is a robust predictor of CVD and all-cause mortality and implicated in pathogenic processes associated with CVD in CKD.

RECENT FINDINGS: In experimental studies, epigenetic modulation of ALP by microRNAs or bromodomain and extraterminal (BET) protein inhibition has shown promising results for the treatment of CVD and other chronic metabolic diseases. The BET inhibitor apabetalone is currently being evaluated for cardiovascular risk reduction in a phase III clinical study in high-risk CVD patients, including patients with CKD (ClinicalTrials.gov Identifier: NCT02586155). Phase II studies demonstrate an ALP-lowering potential of apabetalone, which was associated with improved cardiovascular and renal outcomes.

SUMMARY: ALP is a predictor of CVD and mortality in CKD. Epigenetic modulation of ALP has the potential to affect several pathogenetic processes in CKD and thereby improve cardiovascular outcome.

Hälso- och sjukvårdslagen föranstaltar om en kostnadseffektiv och jämlik diagnostik inom den svenska hälso- och sjukvården. Samtidigt ökar efterfrågan på laboratorietest mer än annan medicinsk aktivitet, och utvecklingen leder även till att utbudet av laboratorietest ökar [1]. Vårdens generella resursbrist har lett till ökad betoning på värdeskapande testanvändning globalt [2] med fokus på såväl underanvändning av test (försenar korrekt diagnos och adekvat behandling) som överanvändning (medför överdiagnostik och resursslöseri) [3].Som en följd av denna utveckling har laboratorieverksamheten inom Region Östergötland initierat strategier med syfte att åstadkomma en mer rationell användning av laboratoriemedicinska analyser. Detta har skett genom en aktivare uppföljning av beställningsmönster åtföljd av information och feedback i relation till observerade beställningsmönster. År 2016 initierades s k KRAMA-strategier (KRAMA = Kompetensgruppen för rationell användning av medicinsk diagnostik i alla delar av vårdkedjan) (Figur 1). En viktig ambition var att överge ett passivt testinförande till förmån för ett mer effektivt införande i kombination med aktiv uppföljning av beställningsmönster.

Systematic reviews and meta-analyses have shown that there is little justification for vitamin D supplements to prevent infections, cancer and cardiovascular disease. Despite the limited evidence of effectiveness, the total number of ordered serum 25-hydroxyvitamin D (25(OH)D) tests has increased considerably in recent years. There seems to be an overuse of this test that does not provide meaningful benefit for patients. A passive introduction of new tests leads generally to a slow initiation of value-based diagnostics, as well as overuse and underuse of diagnostic tests. In this study, in Region Östergötland, we applied a »Choosing wisely« model that reversed a rising trend of 25(OH)D tests and reduced the number of unnecessary tests. The findings point to the need for strategic plans for introducing new analyses and approaches to counteract misuse of laboratory diagnostics. We recommend »Choosing wisely« models for the introduction of new analyses to facilitate appropriate laboratory diagnostics and to counteract long-term overuse.

This prospective study investigated growth and skeletal development for 3years after kidney transplantation in pediatric patients, 3.4-15.0years of age. Growth, BMD, bone resorption markers (CTX and TRACP5b), bone formation markers (PINP, ALP, and osteocalcin), PTH, and vitamin D were assessed at start, 3, 12, and 36months after transplantation. Median GFR was 63 (range 37-96) mL/min/1.73m(2) after 3years. The median height SDS increased from -1.7 to -1.1, and median BMI SDS increased from -0.1 to 0.6 over 3years, which shows that transplantation had a favorable outcome on growth. Fat mass increased after transplantation at all time points, whereas lean mass increased after 1year and 3years. Total BMC increased at all time points. No changes were observed for total BMD. Bone resorption markers decreased initially after 3months and remained stable throughout the study, whereas the bone formation markers decreased initially, but successively increased over the study period. In conclusion, this study demonstrates that height SDS and BMI SDS increased, along with the increased formation markers that reveal a positive bone acquisition after kidney transplantation, which was reflected by the significant increase in total body BMC.

Age- and gender-specific reference intervals are pivotal to ensure appropriate interpretation of plasma alkaline phosphatase activities in the lower range Hypophosphatasia (HPP) is an inborn error of metabolism caused by loss-of-function mutations of the ALPL gene that mainly express alkaline phosphatase (ALP) in bone and liver. The clinical expression of HPP is highly variable and is classified into six different forms mainly affecting bone and tooth mineralization. The prognosis for each of these HPP forms depends upon the severity of the skeletal disease which reflects the age at presentation. The biochemical hallmark of HPP is low plasma ALP activity (hypophosphatasemia); however, HPP is often misdiagnosed because of low awareness and sometimes absence of age- and gender-specific ALP reference intervals. Children and adolescents have higher ALP levels in comparison with adults. Reliable reference intervals are pivotal for any clinical laboratory test. Harmonized age- and gender-specific plasma ALP reference intervals ought to be used to ensure appropriate interpretation of plasma ALP activities in the lower range.

Objective: To describe an intensive nutrition therapy for hospitalized adolescents and young adults with anorexia nervosa (AN) in terms of body weight, body composition, energy balance and food related anxiety. Method: Twenty-six young females, 16-24 years of age, with AN were invited to participate at admission to a specialized eating disorder unit in Goteborg, Sweden. Intensive nutrition therapy comprised 12 weeks on a structured meal plan. Six meals were served daily, in combination with high-energy liquid nutritional supplements from start. Energy and nutrient intakes, energy expenditure, body composition and food related anxiety were measured during the study. A 3-month follow-up of body weight and food related anxiety was conducted. Results: Twenty-one patients participated. The total daily energy intake was, during the first week of treatment, (mean +/- SD) 3264 +/- 196 kcal (74 kcal/kg), and decreased gradually during treatment to 2622 +/- 331 kcal (49 kcal/kg). Total daily energy expenditure was initially 1568 +/- 149 kcal and increased gradually to 2034 +/- 194 kcal. Patients gained on average 9.8 +/- 2.1 kg and body mass index increased from 15.5 +/- 0.9 to 19.0 +/- 0.9 kg/m(2). Body fat increased from 13 +/- 6% to 26 +/- 6%. Fat free mass remained unchanged, but skeletal muscle mass increased from 16.7 +/- 2.0 to 17.6 +/- 2.4 kg, p = 0.009. Patients food related anxiety decreased significantly during treatment and was still unchanged 3 months later. Conclusion: The presented intensive nutrition therapy with initially high energy and nutrient intakes produced substantial weight gain, increased fat and muscle mass and decreased food related anxiety in AN patients, without any clinical side effects. (C) 2016 Elsevier Ltd. All rights reserved.