Increased plasma cholesterol levels are listed between the major
atherosclerosis risk factors. The final plasma cholesterol levels
result from the interplay between the genetic and environmental
(diet, physical activity) factors. Little is known, how dietary
factors influence epigenetics. We have analyzed, if an overgeneration feeding of rat with cholesterol influences total liverDNA methylation, and if total liver-DNA methylation differ
between the different rat strains (Prague hereditary
hypercholesterolemic rats, Prague hereditary hypertriglyceridemic
rats and Wistar Kyoto rats). The animals were feed with high fat
(additional 5 % over normal capacity) high cholesterol (2 %) diet
for 14 days. DNA methylation in the liver tissue in different
generations was analyzed using the liquid chromatography
coupled with tandem mass spectrometry. We have not observed
any significant changes in total liver-DNA methylation over the
9 generations of animals feed by fat/cholesterol enriched diet.
Additionally, there were no differences in DNA methylation
between different rat strains. In animal model, the dietary
changes (hypercholesterolemic diet) not significantly influence
the total DNA methylation status within the liver.
The study explores a latent structure of perceived impacts on the country. Perceived controllability of the context shapes individual plans and forms resource for dealing with changes. The direct and indirect exposure to global challenges (e.g., terrorist attacks) can change individual views of the controllability of the context and lead to negative psychological consequences. On the basis of the analysis, a set of perceived impacts was included in the investigation – impacts on a person, people of Latvia, its political institutions, and global players and threats – as factors representing different levels of ecological systems. Six hundred forty-seven university students from Riga, Valmiera, and Daugavpils participated in the study. The Future of Country Questionnaire was modified and used for the assessment of perceived impacts on Latvia. Exploratory and confirmatory factor analyses provided evidence for four main factors representing perceived impacts: personal control, political power, globalization, and global threats. The latter factor involved military tension and terrorism. Revealed links between control beliefs confirmed the interconnectedness of sub- and super-ordinated ecological systems. Cooperation with other people can facilitate the sense of controllability of the macro-societal context. and Tato studie zkoumá latentní strukturu vnímaných dopadů na stát. Vnímaná ovladatelnost kontextu dotváří jednotlivé plány a formuje zdroje pro vyrovnávání se se změnami. Přímé a nepřímé vystavení globálním výzvám (např. teroristickým útokům) může změnit individuální pohled na kontrolovatelnost kontextu a vést k negativním psychologickým důsledkům. Na základě této analýzy byla do šetření zahrnuta sada zkoumaných vnímaných dopadů – na danou osobu, obyvatele Lotyšska, politické instituce a globální aktéry a hrozby, coby faktory reprezentující různé úrovně vnějších systémů. Studie se zúčastnilo 647 univerzitních studentů z Rigy, Valmiery a Daugavpils. K hodnocení vnímaných vlivů na Lotyšsko byl použit modifikovaný dotazník Budoucnost země. Exploratorní a konfirmační faktorová analýza podpořila čtyři hlavní faktory reprezentující vnímané dopady: osobní kontrolu, politickou moc, globalizaci a globální hrozby, přičemž poslední faktor zahrnoval vojenské napětí a terorismus. Zjištěné souvislosti přesvědčení o kontrolovatelnosti potvrdily provázanost mezi podřízenými a nadřízenými vnějšími systémy. Spolupráce s ostatními lidmi může posílit pocit vlivu (kontroly).
Through their receptors at each level of hypothalamo-pituitarygonadal axis glucocorticoid excess, either endogenous or administered or stress-induced, could affect steroid production in the testis and thus male fertility. The main ways by which glucocorticoids act are as follows: 1) Affecting gonadoliberin and LH synthesis and release through glucocorticoid receptors in hypothalamic neurons and pituitary gonadotropes. 2) By so far not clearly evidenced reduction of the number of LH receptors on the membrane of Leydig cells. 3) By affecting expression and function of steroidogenic enzymes in the testis. 4) By regulation of in situ access of glucocorticoid to its target cells in the testis. 5) By promotion Leydig cell apoptosis. The review provides a survey of physiological and molecular mechanisms staying behind these effects. It does not deal with the clinical effects of glucocorticoid treatment which would substantially exceed the scope of the pater., Richard Hampl, Luboslav Stárka., and Obsahuje bibliografii
Recently, there has been rapidly growing interest in the effects of the microbiota on host physiology and behaviour. Due to the nutritional value of bacteria, gut microflora may be particularly important in species that present nuptial gifts during courtship. Here, we explore whether the presence or absence of gut microbiota in males and females of the nuptial gift-giving species Drosophila subobscura (Collin, 1936) alters mating behaviour in terms of female preference, male investment, and female fecundity. We found that females that had been fed antibiotics, compared to females with intact gut bacteria, were more willing to mate with a male that had been fed normally. However female fecundity was higher when both males and females lacked gut bacteria compared to both individuals having a full complement of gut bacteria. This implies that the presence of the microbiota acts to reduce female fecundity in this species, and that male gut bacterial content influences female fecundity. Our results provide further evidence to the growing consensus that the microbiota of an individual may have important effects on both reproductive behaviour and physiology, and suggest that it may also contribute to the nutritional value of the nuptial gift in this system., Benjamin S. Walsh, Chloe Heys, Zenobia Lewis., and Obsahuje bibliografii