SciCombinator

Discover the most talked about and latest scientific content & concepts.

Journal: Scandinavian journal of clinical and laboratory investigation

28

While von Willebrand factor (vWF) has been reported to be elevated in smokers, there are no reports on the effects of smoking on its cleaving protease ADAMTS-13, particularly in subjects of Arab ethnicity. This study was conducted to determine the effects of smoking on vWF and ADAMTS-13 antigen and activity levels in Arab males. Venous blood samples from 80 smoking (at rest) and 80 non-smoking healthy males were collected after asking subjects to fast and refrain from smoking for 8 hours. Similar sampling was done for 40 smokers (acute smokers), who were asked to smoke one cigarette immediately before blood collection. Plasma was used to measure ADAMTS-13 antigen and activity levels, as well as vWF antigen and collagen binding activity levels using commercial ELISA kits. Compared to non-smokers, ADAMTS-13 and vWF activities were significantly lower in smokers at rest (p < 0.05). Acute smokers had significantly higher levels of vWF activity and ADAMTS-13 antigen and activity levels (p < 0.01), compared to smokers at rest. Our results suggest that high vWF activity is accompanied by an increase in ADAMTS-13 activity as a natural physiological mechanism to degrade the elevated vWF molecules. If not followed by a subsequent smoke, the activities of both proteins subside. It is possible that the repeated increase in vWF and constant degradation by ADAMTS-13 results in lower overall levels of both proteins in smokers (at rest) compared to nonsmokers who do not experience a similar (repeated) injury to the endothelium.

Concepts: Blood, Platelet, Hematology, Von Willebrand factor, Von Willebrand disease, ABO blood group system, Heyde's syndrome, Weibel-Palade body

27

Introduction. Besides hypogammaglobulinemia and recurrent infections, abnormalities of T-cells might contribute to lung damage in common variable immunodeficiency disorders (CVID). Materials and methods. In 16 adult patients, the majority of whom had pulmonary abnormalities, we studied T-cell subsets and markers of inflammation in bronchoalveolar lavage fluid (BALF) and blood and their relations with pulmonary function and high resolution computed tomography (HRCT). Results. We demonstrated that some of the lymphocyte abnormalities previously demonstrated in peripheral blood from CVID patients, such as low CD4/CD8 T-cell ratio, were also present in BALF. Moreover, low BALF CD4/CD8 ratio (≤ 1), found in seven patients, was significantly associated with higher blood CD8(+) cell count and to lower values of the lung function variables; forced expiratory volume (FVC), total lung capacity (TLC), vital capacity (VC) and residual volume (RV) in % of predicted. The expression of the inflammatory markers HLA-DR and CCR5 on T-cells was significantly higher, and the expression of CCR7 significantly lower, in BALF compared to blood, possibly reflecting an inflammatory/cytotoxic T-cell phenotype within pulmonary tissue in CVID. Furthermore, patients with bronchiectasis had higher concentrations of the pro-inflammatory cytokine TNFα in plasma, compared to those without. Conclusion. Our findings suggest that inflammation and T-cell activation may be involved in the immunopathogenesis of pulmonary complications in CVID.

Concepts: Immune system, Pulmonology, Asthma, Lung, Respiratory physiology, Bronchoalveolar lavage, Lung volumes, Spirometer

27

Background. Unbound iron binding capacity (UIBC) in serum, which is s-total iron binding capacity (2 times s- transferrin) minus s-iron, may be a more accurate marker of empty iron stores than serum transferrin saturation. Previously we have shown this for healthy females of childbearing age. Methods. Now we used receiver operating characteristic (ROC) curve analysis to compare the diagnostic accuracy of s-iron, s-transferrin, s-transferrin saturation and s-UIBC in diagnosing empty iron stores in 29,251 female and 19,652 male outpatients. Empty iron stores were defined as s-ferritin less than 10, 15 or 20 μg/L. Results. At all definitions of empty iron stores s-UIBC had a better diagnostic accuracy than the other tests in both male and female outpatients, with an area under the ROC curve of 0.85-0.97. Also in subpopulations with elevated s-CRP or low b-hemoglobin s-UIBC was more accurate than the other tests. All tests performed better in males than in females, and generally they were more accurate in adults than in children. Conclusion. When diagnosing empty iron stores calculation of s-UIBC is a better way to utilize the information in s-iron and s-transferrin than the calculation of s-transferrin saturation.

Concepts: Male, Female, Receiver operating characteristic, Transferrin, Transferrin saturation, Serum iron, Total iron-binding capacity

27

Objectives. The aim of this study was to determine the normal values of serum IGF-1 and IGFBP-3 in Turkish children and adults (1-79 years). Material and methods. The study included 571 healthy children and 625 healthy adults from the West Black Sea region of Turkey. Serum IGF-1 and IGFBP-3 concentrations were determined using a chemiluminescent immunometric assay on an Immulite 1000 analyzer. Results. IGF-1 and IGFBP-3 levels tended to be higher in girls compared to boys among the children. The differences were statistically significant in puberty from age 12-14 years for IGF-1 and prepubertally from age 9-10 years for IGFBP-3. Peaks of serum IGF-1 levels were observed 2 years earlier in girls (14 years) than boys (16 years). The general pattern of IGFBP-3 was similar to IGF-1 during puberty. In adults, IGF-1 and IGFBP-3 levels decreased by age. There was no significant difference in IGF-1 and IGFBP3 values between men and women in any age group. Conclusions. This study established age- and sex-specific reference values for serum IGF-1 and IGFBP-3 in healthy Turkish children and adults.

Concepts: Statistical significance, Insulin-like growth factor 1, Difference, Growth factors, Turkey, Insulin-like growth factor, IGFBP3, Black Sea

26

To evaluate pre-analytical variables of circulating cell-free nucleosomes containing 5-methylcytosine DNA (5mC) or histone modification H3K9Me3 (H3K9Me3).

Concepts: DNA, Histone, Nucleosome, Chromatin

0

To investigate the effect of insulin resistance (IR) on thyroid function, thyroid autoimmunity (AIT) and thyroid volume in type 1 diabetes (T1DM). 100 consecutive patients with T1DM aged 29 (±6) years with diabetes duration 13 (±6) years were included. Exclusion criteria were: history of thyroid disease, current treatment with L-thyroxin or anti-thyroid drugs. Evaluation of thyroid stimulating hormone (TSH), free thyroid hormones and anti-thyroid antibodies was performed. Thyroid volume was measured by ultrasonography. IR was assessed using the estimated glucose disposal rate (eGDR) formula. In the study group 22% of subjects had insulin resistance defined as eGDR lower or equal to 7.5 mg/kg/min. The prevalence of thyroid autoimmunity (positivity for ATPO or ATg or TRAb) in the study group was 37%. There were no significant differences in the concentration of TSH, FT3, FT4, the prevalence of AIT and hypothyroidism between IR and insulin sensitive (IS) group. Mean (±SD) thyroid volume was 15.6 (±6.2) mL in patients with IR and 11.7 (±4.7) mL in IS subjects (p = .002). Thyroid volume correlated inversely with eGDR (r = -0.35, p < .001). In a multivariate linear regression model the association between thyroid volume and eGDR was independent of sex, age, duration of diabetes, daily insulin dose, BMI, cigarette smoking, TSH value and presence of thyroid autoimmunity (beta: -0.29, p = .012). Insulin resisance is associated with larger thyroid volume in patients with type 1 diabetes independently of sex, body mass index, TSH value and presence of autoimmune thyroid disease.

Concepts: Linear regression, Insulin, Diabetes mellitus, Hormone, Hypothyroidism, Hyperthyroidism, Thyroid hormone, Graves' disease

0

Urine erythrocyte (Ery) and leukocyte (Leu) dipstick tests are essential for detecting microhematuria and urinary tract infection. Currently, there is no suggestion for establishing the cut-off limits in an ordinal scale test. This study aimed to establish the cut-off limits for urine Ery and Leu dipstick tests via probit regression. From 1 January 2016 to 30 June 2016, laboratory data were collected from patients at one teaching hospital whose specimen had analytical results from both a urine dipstick test and an automated urine particle analyzer. Probit regression was used to estimate the probability of positive urine dipstick results as a function of log-transformed urine Ery and Leu concentrations. Based on the analysis of 22,122 specimens, the estimated concentration that yields 50% positive results (C50) of the Ery weak+, 1+, 2+, 3+, and 4 + dipstick results were 14.6, 40.4, 51.6, 136.3 and 219.0 × 106/L, respectively. The estimated C50 of the Leu 1+, 2+ and 3 + dipstick results were 22.7, 67.9 and 283.9 × 106/L, respectively. The estimated values were different from arbitrary concentrations provided for each dipstick category by the manufacturer. If a quantitative comparison method/procedure is available, the cut-off limits of an ordinal scale test can be established using probit regression. Each laboratory should investigate the transferability of the arbitrary concentrations provided by the manufacturer, and if necessary, determine its own cut-off limits of urine Ery and Leu dipstick tests.

Concepts: Kidney, Statistics, Blood, Urinary tract infection, Urine, 2016

0

In vitro expanded adipose-derived stromal cells (ASCs) are a useful resource for tissue regeneration. Translation of small-scale autologous cell production into a large-scale, allogeneic production process for clinical applications necessitates well-chosen raw materials and cell culture platform. We compare the use of clinical-grade human platelet lysate (hPL) and fetal bovine serum (FBS) as growth supplements for ASC expansion in the automated, closed hollow fibre quantum cell expansion system (bioreactor). Stromal vascular fractions were isolated from human subcutaneous abdominal fat. In average, 95 × 106 cells were suspended in 10% FBS or 5% hPL medium, and loaded into a bioreactor coated with cryoprecipitate. ASCs (P0) were harvested, and 30 × 106 ASCs were reloaded for continued expansion (P1). Feeding rate and time of harvest was guided by metabolic monitoring. Viability, sterility, purity, differentiation capacity, and genomic stability of ASCs P1 were determined. Cultivation of SVF in hPL medium for in average nine days, yielded 546 × 106 ASCs compared to 111 × 106 ASCs, after 17 days in FBS medium. ASCs P1 yields were in average 605 × 106 ASCs (PD [population doublings]: 4.65) after six days in hPL medium, compared to 119 × 106 ASCs (PD: 2.45) in FBS medium, after 21 days. ASCs fulfilled ISCT criteria and demonstrated genomic stability and sterility. The use of hPL as a growth supplement for ASCs expansion in the quantum cell expansion system provides an efficient expansion process compared to the use of FBS, while maintaining cell quality appropriate for clinical use. The described process is an obvious choice for manufacturing of large-scale allogeneic ASC products.

Concepts: Gene, Human, Chromosome, Cell biology, Biotechnology, Cellular differentiation, Regeneration, Cell culture

0

Dual antiplatelet therapy is recommended in patients undergoing primary percutaneous coronary intervention (p-PCI) for ST-segment elevation myocardial infarction (STEMI). Pre-analytical variables may influence platelet function analysis results. Our aim was to evaluate the on-treatment platelet reactivity in peripheral artery vs coronary blood in patients with STEMI. We enrolled one hundred and nine patients who consecutively underwent p-PCI at Cardiology Unit of Padua University Hospital between June 2014 and June 2015. Before the procedure, all patients received intravenous aspirin 250 mg and either of the thienopyridines; clopidogrel 600 mg, prasugrel 60 mg or ticagrelor 180 mg. ASPI-test and ADP-test using multiple electrode aggregometry (MEA) were performed in samples collected from both a peripheral artery and the culprit coronary artery. ‘Low responders’ were patients with an ASPI-test or ADP-test value greater than or equal to a pre-established normal range. No significant differences were observed in ASPI-test values between peripheral (19 (median) [3-49 (10-90 percentiles)] U) vs coronary (12 [1-40] U, p = .06) blood and in ADP-test (40 [14-82] U vs 33 [7-79] U, p =.68) blood. In peripheral blood, fifteen (14%) patients were ‘low aspirin’ and forty-one (38%) ‘low thienopyridines’ responders. The prevalence of ‘low clopidogrel’ responders was higher (45%) than prasugrel (36%) and ticagrelor (33%). Similar results were observed in coronary blood. In patients undergoing p-PCI for STEMI, MEA platelet function observed in coronary arteries was consistent with peripheral artery blood’s independently of the antiplatelet drug used. The clinical significance of peripheral and coronary on-aspirin/thienopyridines platelet reactivity needs further clarification.

Concepts: Myocardial infarction, Atherosclerosis, Cardiology, Heart, Atheroma, Clopidogrel, Artery, Aspirin

0

Few years ago, it was proposed that everolimus blood levels could be determined with the commercially available sirolimus chemiluminescence magnetic microparticle immunoassay (CMIA). More recently, a highly specific microsphere system (QMS) has been approved by FDA for therapeutic drug monitoring in humans. Aim of the present study was to compare the results of everolimus assay performed with everolimus QMS and with sirolimus CMIA. The two methods were compared with Passing-Bablok regression and Bland-Altman plot analysis. The Passing-Bablok regression analysis showed that although the results obtained with the two techniques were significantly correlated, CMIA-measured differed from QMS-measured everolimus concentrations by both a systematic and a proportional error. Specifically, at blood levels lower than 5 ng/mL CMIA were lower than QMS-measured everolimus concentrations. On the opposite, at everolimus blood concentrations higher than 10 ng/mL CMIA-estimated values became progressively higher than QMS-measured everolimus concentrations. The analysis of the Bland Altman plot showed a less than optimal agreement of the two tests (5.59% of the data point outside the ±1.96 SD interval). Moreover, the relationship between the difference between EveroQMSand EveroCMIAand their average was clearly concentration dependent with positive and negative values at concentration values lower and higher than 5 ng/mL respectively. In conclusion, our finding showed that the values of everolimus concentrations measured with sirolimus CMIA differ from those detected with the FDA-approved everolimus QMS further suggesting that sirolimus CMIA should not be used anymore for everolimus therapeutic drug monitoring.

Concepts: Regression analysis, Linear regression, Comparison, Blood, Concentration, Analytical chemistry, Errors and residuals in statistics, Bland–Altman plot