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The electron β-irradiation of isotactic polypropylene (iPP) influenced the sample chemical structure because it mostly caused the crosslinking of the polymer chains beside the macromolecule degradation. The irradiation effect led to the corresponding changes in physical properties (crystallinity, crystal size, melting and crystallisation temperatures). The amount of the β-phase in the samples decreased with the increasing β-irradiation dose, changing into the α - and amorphous phase. After the irradiation, the iPP melting and crystallisation temperatures decreased, and the spherulitic structure was partially decomposed. The imbibition of boiling xylene proved that the highest degree of crosslinking took place in the samples irradiated with a dose of 33 kGy, showing the highest crystallinity and melting temperature., IGA/FT/2017/002, Tomas Bata University in Zlin [IGA/FT/2017/002]

This article deals with the lifetime of laminated materials produced by different production technologies (hand lamination technology, vacuum bagging technology and prepreg technology with curing in the oven) during cyclic repeated bending stress. Like tested materials composite systems were chosen composite systems with epoxy matrix and carbon reinforcement (Kordcarbon CC200T, epoxy resin with trade name L285) and second composite epoxy system with glass reinforcement (Quadra-axial glass fabric, named Saertex Q-E-820, epoxy resin Biresin CR 82 and third prepreg systems (unidirectional prepreg, trade name Deltapreg VV430U-DT860W-39% and prepreg system with glass fabric VV320P_DT806R-37%). Fatigue tests were performed by cyclic bending loads during a three-point arrangement on a universal servo-hydraulic testing machine INSTRON 8871. Experimentally the number of cycles fracture of the material was determined at 90 % and 80 % of the maximum breaking load., TBU in Zlin [IGA/FT/2019/001, RVO/FT/2019/003]

Objective Mean platelet volume is arousing increasing interest as a new independent cardiovascular risk factor. Large platelets are likely to be more reactive. If mean platelet volume would drop after LDL-lowering therapy, decreased MPV could be one of the markers of successful therapy. Therefore, we investigated mean platelet volume after extracorporeal LDL-cholesterol elimination. Methods Mean platelet volume was investigated in patients with severe familial hypercholesterolemia long-term treated (3–12 years) by LDL-apheresis (immunoapheresis) or cascade filtration. Plasma was obtained by centrifugation. Adsorbers Lipopak 400 were used for immunoapheresis and filters Evaflux 4A were used for cascade filtration. 95 pair samples were measured (before and after the procedures) in a group of 12 patients – each patient 8 times in 4 years. Results Mean platelet volume before the procedures was 10.891 fl, CI 10.25–11.53. Mean platelet volume after the procedures decreased – 10.478 fl, CI 09.84–11.11. The difference is statistically significant ( p = 0.036). Mean platelet volume did not correlate with age, sex, platelet count, duration of therapy. At the same time, we used rheohemapheresis in the therapy of 40 patients with age-related macular degeneration. But mean platelet volume was not changed. Conclusion Mean platelet volume is easily available and is often disregarded, and sometimes may suggest the need for a careful assessment in patients with familial hypercholesterolemia. Mean platelet volume could be one of the markers of therapeutic efficacy in patients with familial hypercholesterolemia treated by extracorporeal LDL-cholesterol elimination that is simple and inexpensive.

Numerous abnormalities of thyroid hormones in end-stage renal disease (ESRD) have been described. Our aim was to analyze the impact of these abnormalities on survival. In 167 hemodialyzed ESRD patients, TSH and thyroid hormone levels (T4, fT4, T3, fT3, rT3) were determined. The patients were then prospectively followed up for up to 5 years and the possible impact of any observed abnormalities on their mortality was studied. Only 16.8 % patients had all six tests within the reference range. The pattern of nonthyroidal illness syndrome was found in 56.3 %. Low T3 was particularly common (44.3 %), and clearly associated with increased 6- and 12-month mortality and decreased overall survival (log rank test, P=0.007). Independent of T3 levels (Spearman correlation, NS), increased rT3 was more frequently observed (9.9 %) than expected from the literature, and was also related to increased mortality and decreased survival (log rank test, P=0.021). Increased rT3 may be more common in ESRD patients than previously described, and together with decreased T3 it may serve as an indicator of poor prognosis in subsequent months.

Fetuin-A is a calcification inhibitor, negative acute phase response marker and cardiovascular mortality predictor in hemodialysis patients. Low levels of fetuin-A are associated with malnutrition, inflammation, decreased bone mass density, low-turnover bone and use of high calcium concentration dialysate. Hemodialysis procedure (HD) has been shown to decrease fetuin-A levels by 20%, probably due to HD-induced inflammation or acute changes in calcium metabolism. The aim of our study was to investigate effects of HD on serum fetuin-A levels. Forty clinically and hemodynamically stable hemodialysis patients (21 females, 68 (38-85) years) underwent routine bicarbonate hemodialysis or hemodiafiltration with polysulfone dialyzer. On consecutive HD dialysis solution with different calcium concentration with/without citric acid was used to assess influence of calcium shifts and parathyroid activity on fetuin-A changes during HD. All other parameters of HD were kept constant. Serum fetuin-A, calcium, phosphorus, iPTH, CRP and other biochemical parameters were measured before and after each HD. Our data show that predialysis serum fetuin-A levels have positive correlation with iPTH levels (p