Spontaneous contractions of isolated rat portal vein under temperature perturbations

We studied nonlinear dynamics underlying spontaneous rhythmical contractions of isolated rat portal vein. The signals were acquired at four different temperatures important in isolated blood vessels preparations: 4, 22, 37 and 40°C. To characterize the system’s nonlinearity, we calculated the largest Lyapunov exponent, sample entropy and scaling exponents. Evidence for nonlinearity was provided by analysis of surrogate data generated from the phase-randomized Fourier transform of the original sequences. Positive values of the largest Lyapunov exponent were obtained for the time series recorded under applied conditions, indicating that the system preserves its chaotic deterministic nature even far from the physiological temperature range. Scaling exponents revealed three distinctive regions with different correlation properties. The calculated measures that characterize the time series obtained at 4°C were significantly different from those derived from data obtained at higher temperatures. System’s dynamics becomes more complex or less predictable as temperature approaches physiological value. The computation of the largest Lyapunov exponent, sample entropy and correlation measures gave an insight into the complex dynamics of the isolated blood vessels rhythmicity. We identified different modes of rhythmical contractions of isolated rat portal vein which could improve understanding of possible control mechanisms in vivo.     

Light of the stars: calcium signals light up astrocytes in the presence of autoreactive CD4~+ T cells

正Introduction:Astrocytes play important roles in the central nervous system CNS to support and regulate CNS function.They are abundant type of glia that form a meshwork of intercon nected cells almost completely tiling the CNS.Each astrocyte extends densely ramified processes that establish close contacts and interaction with other astrocytes,     

Heart insufficiency in traumatic arteriovenous fistulas

Objective: To analyse the incidence, clinical presentation, and outcome of heart insufficiency in patients with chronic arteriovenous fistulas (AVF). Methodology: From 1991 to 2000 we treated 49 patients with traumatic AVF. The present study included 19 patients with AVF present for 6 months or longer, as it was presumed that these AVF will have an impact on cardiac overload. There were 16 male and three female patients with a mean age of 36 years (17–59). The time from injury to admission varied from 6 months to 33 years. Cardiological examination checked for dyspnoea and palpitation. ECG, chest X‐ray and ECHO‐cardiography were also performed. All AVF were deleted, magistral vessels reconstructed, non‐magistral obliterated, either surgically or by percutaneous embolization. Results: Mean follow up was 44.2 months (3–93). Serious heart insufficiency was seen in two patients only, with AVF in the subclavial vessels. Both suffered from serious heart disease prior to the therapeutic procedures that resulted in iatrogenic AVF, so it was difficult to connect heart insufficiency to the AVF alone. Despite surgical closure of AVF and intensive medical treatment, signs of heart insufficiency remained in both patients. Signs of cardiac overload were seen in six patients with long‐standing AVF in major vessels. Except for one patient who refused surgical closure of femoral AVF, the remaining five were symptom free for cardiac overload during the follow‐up period. Conclusion: In our series, heart insufficiency was an infrequent complication in long‐standing AVF, even when major vessels were involved.     

The burden of disease and injury in Serbia

BACKGROUND: In the last decade of the 20th century, a considerable effort has been put into the development of summary measures of population health that combine information on mortality and non-fatal health outcomes. We used the DALYs (Disability adjusted life years) method to assess the burden of disease and injury in the population of Serbia. METHODS: Our study, largely based on the methods developed for the Global burden of disease study, was conducted between October 2002 and September 2003. DALYs, stratified by gender and age, were calculated for 18 selected health conditions for the population of Serbia, Serbia and Montenegro for 2000. Years of life lost (YLL) were calculated using country mortality statistics, while years lived with disability (YLD) were calculated using different sources of information. Also, the YLD/YYL ratio and age-adjusted rates of DALYs were calculated. RESULTS: Ischaemic heart disease, cerebrovascular diseases, lung cancer, unipolar depressive disorders, and diabetes mellitus were responsible for almost two-thirds (70%) of the total burden of 18 selected disorders in Serbia 2000. The leading five causes for males were ischaemic heart disease (26.1 DALY per 1000), stroke (17.9), lung cancer (12.7), road traffic accidents (6.5), and self-inflicted injuries (5.5). For females, the leading five causes were stroke (18.1 DALY per 1000), ischaemic heart disease (14.1), depression (8.7), breast cancer (6.1), and diabetes mellitus (5.2). CONCLUSIONS: The final results of the study have shown that the national health priority areas should cover cardiovascular diseases, cancers, and mental health.     

Occurrence of Campylobacter, Salmonella, Yersinia enterocolitica and Listeria monocytogenes in some retail food products in Novi Sad

The official reporting system in the Province of Vojvodina (PV) indicates that cases of human salmonellosis were partly covered by complete epidemiological investigation including laboratory analysis of the suspected food. Intestinal campylobacteriosis and yersiniosis and four cases of septicemias caused by Listeria monocytogenes were not fully epidemiologically investigated. Actual country legislation on food safety does not include provisions for a routine control of the above mentioned pathogens except for Salmonella. In the PV, there are no other sources of data that contribute to risk assessment of the above food-borne diseases. A pilot investigation, performed in Novi Sad, indicated that 8.17% out of the total number of 257 retail food samples (90 of fresh meat and 167 of ready-to-eat food) had been contaminated with one of the tested bacteria Campylobacter or Salmonella or Listeria monocytogenes. Yersinia enterocolitica was not detected in any of the tested samples. Fresh poultry meat and other fresh meats were the dominant sources of the detected pathogens compared to samples of ready-to-eat food (p < 0.05). Campylobacter was detected in 18.8% and 10.0% samples of fresh poultry and other fresh meat respectively, which was not statistically significant (p > 0.05). Salmonella was detected in 3.3% samples of fresh poultry meat. Listeria monocytogenes was detected in 5.0% samples of fresh poultry and in 3.3% samples of other fresh meat, the difference was not statistically significant (p > 0.05). One sample (0.6%) of ready to eat food was contaminated with Campylobacter and one (0.6%) with Salmonella.     

Long term prognosis of symptomatic and asymptomatic cerebral aneurysms

The authors analyze the follow-up series of 58 patients with diagnosed cerebral aneurysms who were either not treated surgically or, in surgically treated cases, in which the aneurysmal neck was not clipped. The patients are divided in three groups: untreated ruptured; ruptured treated by coating, vessel ligation or aneurysmal dome clipping; and asymptomatic cases. During the follow-up period of three to ten years, there were no bleedings from asymptomatic aneurysms and only one rebleeding from symptomatic operated aneurysms. As can be expected in the group of ruptured unoperated aneurysms, the rate of rebleeding was 40.9% with a mortality rate of 31.7%. The natural history of asymptomatic aneurysms is unclear regarding the risk of bleeding, and regardless of the obtained follow-up results in our cases, we think that all diagnosed cerebral aneurysms must be treated surgically. Certainly, individual cases must be evaluated.     

Immunoglobulins from sera of antiphospholipid syndrome patients are internalized in the HTR-8/SVneo cell line and cytotrophoblast in culture

Women with antiphospholipid syndrome (APS) experience pregnancy complications mostly due to impaired trophoblast cell functions. Antiphospholipid antibodies (aPL) affect extravillous trophoblast in vivo and in culture, but the mechanisms are still poorly understood. Previously, syncytiotrophoblast was shown to bind and internalize aPL, which was not replicated for extravillous cytotrophoblast in short term culture. Here, aPL binding and time dependent internalization was demonstrated with exposure to aPL in the extravillous cell line HTR-8/SVneo and isolated first trimester of pregnancy cytotrophoblast (CT) using immunocytochemistry and flow cytometry. Intracellular aPL were detectable from 2?h of culture, reaching 30.7?±?3.1% (p?<?0.001) positive cells in CT and 24.8?±?7% (p?<?0.01) in HTR-8/SVneo cells at 24?h and 33?±?4.2% (p?<?0.01) at 48?h. The data presented show that extravillous trophoblast cells internalize aPL in a time-dependent manner significantly more than control immunoglobulins after 24?h of exposure.     

A novel inflammatory role for platelets in sickle cell disease

The severe pain, ischemia and organ damage that characterizes sickle cell disease (SCD) is caused by vaso-occlusion, which is the blockage of blood vessels by heterotypic aggregates of sickled erythrocytes and other cells. Vaso-occlusion is also a vasculopathy involving endothelial cell dysfunction, leukocyte activation, platelet activation and chronic inflammation resulting in the multiple adhesive interactions between cellular elements. Since platelets mediate inflammation as well as thrombosis via release of pro- and anti-inflammatory molecules, we hypothesized that platelets may play an active inflammatory role in SCD by secreting increased amounts of cytokines. Since platelets have been shown to contain mRNA and actively produce proteins, we also hypothesized that SCD platelets may contain increased cytokine mRNA. In this cross-sectional study, we sought to compare both the quantity of cytokines secreted and the cytokine mRNA content, between SCD and control platelets. We measured the secretion of Th1, Th2, and Th17-related cytokines from platelets in a cohort of SCD patients. We simultaneously measured platelet mRNA levels of those cytokines. Platelets from SCD patients secreted increased quantities of IL-1β, sCD40L, and IL-6 compared to controls. Secretion was increased in patients with alloantibodies. Additionally, mRNA of those cytokines was increased in SCD platelets. Platelets from sickle cell patients secrete increased amounts of inflammatory cytokines, and contain increased cytokine mRNA. These findings suggest a novel immunological role for platelets in SCD vasculopathy, in addition to their thrombotic role, and strengthen the rationale for the use of anti-platelet therapy in SCD.     

Conflict between work and family roles and satisfaction among nurses in different shift systems in Croatia: a questionnaire survey

The objective of this study was to examine the perception of conflict between work and family roles and job, family, and life satisfaction among nurses in Croatia. One hundred and twenty-nine nurses (married mothers) working in hospitals in Zadar, ?ibenik, and Split were divided in four groups according to their worktime schedule. The participants completed a survey, which included a set of sociodemographic-type questions, questions about the level and allocation of family responsibilities between spouses, and scales measuring the perceived negative effects of worktime, psychological demands of the work, work-family conflict, and semantic differential scales for measuring the affective and cognitive-evaluative component of job, family, and life satisfaction. This was the first study in Croatia to deal with work-family conflict among nurses or workers with different shift systems.The results of this study indicate that nurses working morning shifts only experienced less conflict between work and family than other groups of nurses, who worked the morning, afternoon, and the night shift. The cognitive-evaluative component of job satisfaction was the highest among morning shift nurses and the lowest in nurses who worked 12-hour shifts, while the affective component of life satisfaction was the lowest in nurses working irregular and backward rotated shifts. These results confirm that shiftwork makes the work-family role conflict even worse. They also support the view that the type of shift rotation matters.