Influence of ceria nanoparticles on chemical structure and properties of segmented polyesters.

In this work, we present new nanocomposite materials derived from segmented copolyesters, comprising ethylene terephthalate (PET) segments and dimerized linoleic acid (DLA), and nanometric cerium oxide particles (CeO2). Nanoparticles were incorporated in situ during polycondensation in various concentrations, from 0.1 up to 0.6 wt.%. It was found that preparation of nanocomposites in situ, during polycondensation, had no significant influence on changes in segmental composition as determined from (1)H and (13)C, as well as 2D NMR. Thermal analysis and calculated degree of crystallinity showed that increasing concentration of ceria nanoparticles lead to an increase in mass content of PET crystallites in hard segments. The XRD investigations also showed an increased intensity of characteristic signals with increasing ceria concentration. Simultaneously, the incorporation of CeO2 led to an increase in tensile strength and elongation at break, indicating a reinforcing and plasticizing effect of ceria nanoparticles. However, the modulus at 10% strain decreased with increasing amount of nanoparticles. The in vitro culture of human cardiac progenitor cells (hCPCs) on the new materials indicated a homogenous cell displacement across the samples after 5 days with no signs of cytotoxicity, indicating good biocompatibility in vitro of CeO2-based nanocomposites and a potential for biomedical applications.

[Detection of silent ischemia symptoms in patients with carbohydrate metabolism disorders]. / Badania nad obecnoscia bezbólowej postaci choroby niedokrwiennej serca u chorych z zaburzeniami gospodarki weglowodanowej.

Early detection of silent ischaemia plays an important role in prevention of sudden cardiac death. Glucose metabolism disturbances are important risk factor of ischaemic heart disease. More frequent occurrence of silent ischaemia in patients with diabetes mellitus has been reported in several studies. We studied 24-hour Holter ECG monitoring of 335 patients with stable angina pectoris. Patients were divided in two groups. The first group consisted of 158 patients with glucose metabolism disturbances, the second-controlled group consisted of 177 patients without these disturbances. The aim of this study was to analyse the frequency of occurrence of silent ischaemia according to the grade of glucose metabolism disturbances. We only found that silent ischaemia is more frequent in patients with higher grade glucose metabolism disturbances. Additionally, we found that more frequent occurrence of silent ischaemia may depend on coexisting hypertension and hypertriglyceridemia. The comparison of Holter ECG monitoring and exercise test in detection of silent ischaemia has shown that both methods are useful in the detection of silent ischaemia.

[A test for evaluating specificity and course of tilt table testing based on two groups of healthy volunteers (adolescent athletic swimmers and controls)]. / Próba oceny swoistosci i przebiegu testu pochyleniowego w oparciu o badania dwóch grup zdrowych ochotników (mlodziezy wyczynowo uprawiajacej plywanie i grupy jej rówiesników).

The aim of this study was to estimate the results of tilt table testing in two groups of healthy adolescents--swimmers and control. Cardio-vascular reactions on tilting were determined by the measurements of heart rate (HR), systolic (SBP) and diastolic blood pressure (DBP). The study was carried out in accordance with the Polish Cardiac Society procedure. The positive tilt table testing results were observed in most young swimmers and in about thirty per cent of controls. The differences in the cardiovascular reactions were observed, too. The clinical interpretation and usefulness of these results must be established by future investigations.

[The role of aluminum in the human body]. / Rola aluminium w organizmie czlowieka.

In the work a contents, dispose, metabolism and physiological role of aluminium in human organism is described. That ion share in etiopathogenesis of many diseases and its compounds application as medicines is taken into consideration.