The incidence of diabetes mellitus is rising worldwide. The aim of this prospective epidemiological study was to compare the effects of natural and surgical menopause on parameters of glucose metabolism. In a group of 587 repeatedly examined women, with a baseline age of 45-55 years, the following subgroups of women were separated: those after bilateral oophorectomy (BO, n=37) and those in natural menopause (NAT, n=380) including women menopausal already at baseline (POST, n=89). The study parameters including glycemia, insulinemia, HOMA-IR and betacell function using HOMA-β were determined at baseline and 6 years later. Over the study period, there was a marked rise in prediabetic and diabetic values of fasting glycemia; the percentage of women with diabetic values increased in the NAT (from 0.8 % to 3.9 %) and POST (from 2.2 % to 9.0 %) subgroups, with the highest prevalence in the BO subgroup (from 8.1 % to 10.8 %). While, among women with non-diabetic fasting glycemia, an increase in fasting glycemia was observed in all study subgroups, it was more marked in the BO subgroup than in the NAT and POST ones (p=0.02 both). This difference between NAT and BO was also found in the long-term trend of development of glycemia in non-diabetic women (p=0.014). Compared with natural menopause, bilateral oophorectomy may have an adverse effect on glucose metabolism., M. Lejsková, J. Piťha, S. Adámková, O. Auzký, T. Adámek, E. Babková, V. Lánská, Š. Alušík., and Obsahuje bibliografii
Infection with the liver fluke Opisthorchis viverrini (Digenea) (Poirier, 1886) causes bile duct injury and periductal fibrosis by chronic overproduction of inflammatory-mediators and eventually results in cholangiocarcinoma development. While extensive research works have been done on O. viverrini infection-associated changes of bile ducts and periductal fibrosis, little attention was paid on morphological and biochemical changes of the bile canaliculi (BC), the origin of bile flow. We aimed to investigate the morphological and functional alterations of BC in the liver of hamsters infected with O. viverrini at one and three months post-infection. Ultrastructural changes of BC showed dilatation of BC and significant reduction of the density of microvilli as early as at one month post-infection. Immunohistochemistry revealed that CD10, a BC marker, expression was reduced early as one month post-infection. The mRNA expression of the genes encoding molecules related to bile secretion including bile acid uptake transporters (slc10a1 and slco1a1), bile acid dependent (abcb11) and independent (abcc2) bile flow and bile acid biosynthesis (cyp7a1 and cyp27a1) were significantly decreased at one month post-infection in association with the reduction of bile volume. In contrast, the expression of the mRNA of bile acid regulatory genes (fxr and shp-1) was significantly increased. These changes essentially persisted up to three months post-infection. In conclusion, O. viverrini infection induces morphological and functional changes of BC in association with the decrease of bile volume.
The study deals with the role, so-called "white ballots" played in the political development of Czechoslovakia in the years 1945-1948. and Článek zahrnuje poznámkový aparát pod čarou
We investigated the gastric response to an ulcerogenic irritant and the change in gastric functions in an experimental rat model of obstructive jaundice, with or without biliary drainage. After biliary obstruction for 14 days, rats with ligated bile duct (BDL) were randomly divided into three groups: BDL group without biliary drainage, BDL followed by choledochoduodenostomy (CD) or a choledochovesical fistula (CVF). The gastric functions were evaluated 2 weeks after the surgery. Gastric damage, induced by orogastric administration of ethanol, was evaluated 30 min later using a lesion index and microscopic scoring was then performed on fixed stomachs. Basal gastric acid secretion was measured by the pyloric ligation method.The lesion index and maximum lesion depth did not differ in the BDL and sham groups, while they were significantly reduced in the CD group. Gastric acid output and secretory volume were reduced in the BDL group compared to the sham group, while these reductions were abolished in the CD group. Afferent denervation with capsaicin further reduced the ulcer index in the later group. Our data suggest that gastric mucosal susceptibility to injury is dependent on the normal flow of bile into the duodenal lumen, which appears to be a requirement for adaptive gastric cytoprotection., A. Cingi, R. Ahiskali, B. K. Oktar, M. A. Gülpinar, C. Yegen, B.Ç. Yegen., and Obsahuje bibliografii
The complex architecture of the liv er biliary network represents a structural prerequisite for the formation and secretion of bile as well as excretion of toxic substances through bile ducts. Disorders of the biliary tract affect a significant portion of the worldwide population, often leading to cholestatic liver diseases. Cholestatic liver disease is a condition that results from an impairment of bile formation or bile flow to the gallbladder and duodenum. Cholestasis leads to dramatic changes in biliary tree architecture, worsening liver disease and systemic illness. Recent studies show that the preva lence of cholestatic liver diseases is increasing. The availability of well characterized animal models, as well as development of visualization approaches constitutes a critical asset to develop novel pathogenetic concepts and new treatment strategies., L. Sarnova, M. Gregor., and Obsahuje bibliografii
We give one sufficient and two necessary conditions for boundedness between Lebesgue or Lorentz spaces of several classes of bilinear multiplier operators closely connected with the bilinear Hilbert transform.
A mathematical model of the microalgal growth under various light regimes is required for the optimization of design parameters and operating conditions in a photobioreactor. As its modelling framework, bilinear system with single input is chosen in this paper. The earlier theoretical results on bilinear systems are adapted and applied to the special class of the so-called intermittent controls which are characterized by rapid switching of light and dark cycles. Based on such approach, the following important result is obtained in the present paper: as the light/dark cycle frequency is going to infinity, the value of resulting production rate in the microalgal culture goes to a certain limit value, which depends on average irradiance in the culture only. As a case study, the so-called three-state model of photosynthetic factory, being a simple four-parameter model, is analyzed. The present paper shows various numerical simulations for the model parameters previously published and analyzed experimentally in the biotechnological literature. These simulation results are in a very good qualitative compliance with the well-known flashing light experiments, thereby confirming viability of the approach presented here.
Bilirubin is the final product of heme catabolism in the systemic circulation. For decades, increased serum/plasma bilirubin levels were considered an ominous sign of an underlying liver disease. However, data from recent years convincin gly suggest that mildly elevated bilirubin concentrations are as sociated with protection against various oxidative stress-mediated diseases, atherosclerotic conditions being the most clinically relevant. Although scarce data on beneficial effects of bilirubin had been published also in the past, it took until 1994 when the first clinical study demonstrated an increased risk of coronary heart disease in subjects with low serum bilirubin levels, and bilirubin was found to be a risk factor for atherosclerotic diseases independent of standard risk factors. Consistent with t hese results, we proved in our own studies, that subjects with mild elevation of serum levels of unconjugated bilirubin (benign hyperbilirubinemia, Gilbert syndrome) have much lower prevalence/incidence of cor onary heart as well as peripher al vascular disease. We have also demonstrated that this association is even more general, with serum bilirubin being a biomarker of numerous other diseases, often associated with increased risk of atherosclerosis. In addition, very recent data have demonst rated biological pathways modulated by bilirubin, which are responsible for observed strong clinical associations., L. Vítek., and Obsahuje bibliografii
The influence of binaries on the evolution of globular clusters is studied numerically using the Monte Carlo method. It is assumed that initially the stellar systems are composed of single stars only and binaries are born /as a result of three-body encounters/ during the evolution of the clusters. The life of each hard binary in the cluster is studied individually. It is shown that the first binaries appear long before core collapse is completed, and then a population of a few hard binaries remains in the cluster during its whole life. Practically all energetic binary-single star interactions take place in the deep, internal parts of the core, populated mostly by the heaviest stars of the cluster. The binary-single star interactions become a source of energy which stops the collapse of the core and causes expansion and gradual disintegration of the whole cluster during the post-collapse phase.