The Relationship between Plasma Soluble Tnf-like Weak Inducer of Apoptosis Level and Inflammatory Markers in Patients with Type 2 Diabetes Mellitus

Soluble TNF-like weak inducer of apoptosis (sTWEAK) is a member of the TNF super family with many biological activities. There is a limited number of studies on the role of sTWEAK in chronic kidney disease. We aimed in this study to examine the relation of sTWEAK with albuminuria and inflammatory markers in patients with type 2 diabetes mellitus (DM). One hundred and eighteen diabetic patients with varying levels of albuminuria were included. Group 1 comprised patients with albuminuria less than 30 mg/day, while Group 2 and Group 3 were composed of patients with albuminuria between 30–300 mg/day or more than 300 mg/day, respectively. Groups were compared for sTWEAK levels besides demographic, clinical and biochemical data. There was no difference between groups regarding sTWEAK and TNF-α levels. IL-1 levels in Group 1 were higher than in Group 3. hsCRP levels were significantly higher in Group 3 compared to other groups. Use of a renin angiotensin system blocker did not have any effect on sTWEAK, TNF-α and hsCRP levels, while IL-1 level was significantly lower in patients using a renin angiotensin blocker. A statistically significant positive correlation was detected between sTWEAK and IL-1 levels (r=0.245; p=0.008). The groups were found to be similar regarding sTWEAK and TNF-α level. This finding may be interpreted as there being no effect of proteinuria on sTWEAK levels. But the close correlation between proteinuria and IL-1, and between IL-1 and sTWEAK may be a clue for an indirect relationship. Lack of difference between groups regarding sTWEAK levels may be due to involvement of patients with GFR more than 60 ml/minute only.

The Relationship between Soluble Tumor Necrosis Factor-like Weak Inducer of Apoptosis Levels and Cardiac Functions in Peritoneal Dialysis Patients

Tumor necrosis factor (TNF)-like weak inducer of apoptosis (sTWEAK) levels has been reported to be decreased in patients on hemodialysis (HD) and patients with heart failure. We aimed to study the relationship between sTWEAK levels and cardiac functions in peritoneal dialysis (PD) patients. This cross-sectional study was carried out on patients on chronic PD programs for more than three months. Patients aged under 18 or over 80 years, patients with overt cardiac disease, overt hypervolemia, active systemic infection, malignancy, peritonitis within the last month were excluded. The patient group was compared with the control group including healthy adults aged 24–61 years. Fifty-two PD patients were included in the study (mean age: 52.7±15.4 years; female/male ratio: 30/22). The corresponding data of the control group were 41.3±10.7 years and 17/14. There was no statistically significant difference between demographic parameters of the groups except age. The mean sTWEAK level of the patient and the control groups were similar (564±17 pcg/ml vs 535±126 pcg/ml, p=0.419). No correlation was detected between any of the demographic variables and sTWEAK levels. Among the echocardiographic parameters, only ejection fraction was found to be correlated negatively with sTWEAK levels. Patients with ischemic heart disease (IHD) and heart failure had significantly higher sTWEAK levels compared with the patients without these diseases. With linear regression analysis, only age and the presence of heart failure were found to be the independent determinants of sTWEAK levels. Level of sTWEAK is significantly high in PD patients with heart failure and IHD. sTWEAK may be a marker of cardiac functions in PD patients.

Is Pentraxin-3 Stronger Than C-Reactive Protein to Determine Inflammation in Peritoneal Dialysis Patients?

Pentraxin-3 (PTX-3) is the prototype of long pentraxins and is produced by many tissues and organs including vascular endothelial cells in response to pro-inflammatory signals. It is thought to be an independent indicator of disease activity. We analyzed the correlation of PTX-3 with other markers of inflammation in peritoneal dialysis (PD) patients. Non-diabetic patients on chronic PD program who meet the dialysis adequacy criteria and who had no active infectious/inflammatory disease were included. Demographic and clinical parameters were recorded as well as hsCRP, fibrinogen, interleukin-6 (IL-6) and PTX-3 levels; and the correlation between them were studied. Twenty-five patients (mean age: 45.7±12.5 years; female/male ratio: 16/9) were included. Mean PTX-3 level was 2.16±2.76ng/ml. PTX-3 was found to be correlated positively with only IL-6 among inflammatory markers (r=0.827; p<0.001) but not with hsCRP. With linear regression model, IL-6 was the only independent determinant of PTX-3 levels. PTX-3 may be a more valuable marker of inflammation than CRP in patients on PD.

Evaluation of Measurement Uncertainty of Glucose in Clinical Chemistry

The definition of the uncertainty of measurement used in the International Vocabulary of Basic and General Terms in Metrology (VIM) is a parameter associated with the result of a measurement, which characterizes the dispersion of the values that could reasonably be attributed to the measurand. Uncertainty of measurement comprises many components. In addition to every parameter, the measurement uncertainty is that a value should be given by all institutions that have been accredited. This value shows reliability of the measurement. GUM, published by NIST, contains uncertainty directions. Eurachem/CITAC Guide CG4 was also published by Eurachem/CITAC Working Group in the year 2000. Both of them offer a mathematical model, for uncertainty can be calculated. There are two types of uncertainty in measurement. Type A is the evaluation of uncertainty through the statistical analysis and type B is the evaluation of uncertainty through other means, for example, certificate reference material. Eurachem Guide uses four types of distribution functions: (1) rectangular distribution that gives limits without specifying a level of confidence (u(x)=a/ radical3) to a certificate; (2) triangular distribution that values near to the same point (u(x)=a/ radical6); (3) normal distribution in which an uncertainty is given in the form of a standard deviation s, a relative standard deviation s/ radicaln, or a coefficient of variance CV% without specifying the distribution (a = certificate value, u = standard uncertainty); and (4) confidence interval.

Lipid peroxidation and antioxidant defence system in patients with active or inactive Behçet's disease

To evaluate plasma lipid peroxidation and enzymatic and non-enzymatic antioxidant systems in patients with Behçet's disease, plasma malondialdehyde levels and total antioxidant status, erythrocyte superoxide dismutase and whole blood glutathione peroxidase activities were studied in 15 patients with active disease and in 30 with inactive disease, and compared with 20 age-matched healthy control subjects. Plasma malondialdehyde levels were significantly higher in patients with active Behçet's disease than in patients with inactive disease, who had significantly higher levels than control subjects. The plasma total antioxidant status of both groups of patients was significantly lower than that of controls. Furthermore, whole blood glutathione peroxidase activity was significantly lower in patients with active versus inactive Behçet's disease. There were no significant differences in erythrocyte superoxide dismutase levels between the groups. In conclusion, there is an increase in oxidative stress in Behçet's disease. Despite this stress, the antioxidant system is deficient and inadequate, especially in patients who are in an active phase of the disease.

Avidin-biotin ELISA for measurement of prothrombin in human plasma

In this study, IgG was partially purified from rabbit antisera against human normal prothrombin. The presence of antibodies against prothrombin was shown by Ouchterlony's double immunodiffusion method. This IgG was adsorbed to microwells and an enzyme-linked immunosorbent assay (ELISA) method was developed by using biotinylated prothrombin. We used alkaline phosphatase as the labeling enzyme. Plasma prothrombin concentrations in 30 healthy individuals and 15 patients with liver cirrhosis were measured using this ELISA method. Prothrombin levels of the cirrhotic patients (61+/-36 microg/ml) were significantly lower than those of the control values (117+/-43 microg/ml) (P<.001). In addition to the ELISA method in the same samples, we assayed prothrombin levels by nephelometry and prothrombin activities using staphylocoagulase and chromogenic substrate. With nephelometry, in healthy individuals, a mean value of 104+/-17 microg/ml and, in cirrhotic patients, a mean value of 51+/-26 microg/ml of prothrombin levels were detected. The prothrombin activities were 10532+/-2429 and 2433+/-330 U/l, respectively. In both methods, the prothrombin values of cirrhotic patients were also significantly lower than those of the healthy individuals (P<.001). The correlation coefficient between ELISA and nephelometry was r=.90, P<.01, and between ELISA and the amidolytic assay was r=.69, P<.01. Prothrombin times (PT) of cirrhotic patients (18.5+/-2.3 s) were significantly longer and albumin (2.4+/-0.5 g/dl) levels were significantly lower than those of normal values (P<.001). PT were negatively correlated with prothrombin levels assayed by ELISA (r=-.59, P<.01). This enzyme immunoassay technique can be used to measure prothrombin levels in plasma.