Thrombotic vascular risk factors in inflammatory bowel disease.

Background--Thrombosis may be an important effector mechanism in the pathogenesis of Crohn's disease.Methods-This study therefore investigated the prevalence of independent thrombotic risk factors (factor VII coagulant activity, lipoprotein (a), fibrinogen, plasma triglycerides, and smoking) in patients with Crohn's disease, ulcerative colitis, and normal controls.Results-In Crohn's disease (n=75), the mean plasma VII:C, lipoprotein (a) and fibrinogen concentrations were significantly greater than in the normal population (n=85). In ulcerative colitis (n=35), only the mean factor VII:C concentration was significantly higher than normal. Ninety three per cent of patients with Crohn's disease and 86% of those with ulcerative colitis had at least one risk factor for thrombotic vascular disease, compared with 61% of the normal population (p<0.001).Conclusions-In many young patients with inflammatory bowel disease, plasma concentrations of these prothrombotic factors were in excess of the limits that are regarded as posing an increased risk for the development of occlusive vascular disease

The research on endothelial function in women and men at risk for cardiovascular disease (REWARD) study: methodology

Background Endothelial function has been shown to be a highly sensitive marker for the overall cardiovascular risk of an individual. Furthermore, there is evidence of important sex differences in endothelial function that may underlie the differential presentation of cardiovascular disease (CVD) in women relative to men. As such, measuring endothelial function may have sex-specific prognostic value for the prediction of CVD events, thus improving risk stratification for the overall prediction of CVD in both men and women. The primary objective of this study is to assess the clinical utility of the forearm hyperaemic reactivity (FHR) test (a proxy measure of endothelial function) for the prediction of CVD events in men vs. women using a novel, noninvasive nuclear medicine -based approach. It is hypothesised that: 1) endothelial dysfunction will be a significant predictor of 5-year CVD events independent of baseline stress test results, clinical, demographic, and psychological variables in both men and women; and 2) endothelial dysfunction will be a better predictor of 5-year CVD events in women compared to men. Methods/Design A total of 1972 patients (812 men and 1160 women) undergoing a dipyridamole stress testing were recruited. Medical history, CVD risk factors, health behaviours, psychological status, and gender identity were assessed via structured interview or self-report questionnaires at baseline. In addition, FHR was assessed, as well as levels of sex hormones via blood draw. Patients will be followed for 5 years to assess major CVD events (cardiac mortality, non-fatal MI, revascularization procedures, and cerebrovascular events). Discussion This is the first study to determine the extent and nature of any sex differences in the ability of endothelial function to predict CVD events. We believe the results of this study will provide data that will better inform the choice of diagnostic tests in men and women and bring the quality of risk stratification in women on par with that of men

Electron microscopy of <i>Eimeria acervulina</i> macrogametogony and oocyst wall formation

SummaryMacrogametogony and the formation of the oocyst wall has been examined in Eimeria acervulina. Macrogametes develop within a parasitophorous vacuole. Within the cytoplasm can be observed wall-forming bodies of Type I (WFBI). and Type II (WFBII), a nucleus, mitochondria, canaliculi and polysaccharide granules. WFBII are unusual in possessing a membrane internal to the granular endoplasmic reticulum. Formation of the outer layer of the oocyst wall is preceded by the separation of a veil membrane, and accompanied by morphological changes in the WFBI. WFBI material is deposited between the veil-forming membrane and the two cytoplasmic membranes. A newly formed membrane divides this outer layer during its early development. The inner layer of the oocyst wall is formed from WFBII material which is deposited between the cytoplasmic limiting membranes. The outer layer of the oocyst wall consists of granular and osmiophilic parts, but the inner layer of the wall is homogenous.</jats:p

The ultrastructural development of the oocyst wall of <i>Eimeria maxima</i>

SUMMARYOocyst wall formation in Eimeria maxima was studied during the macrogamete stage in intestinal cells of the chick and in unsporulated oocysts isolated from faeces. The outer of the 2 membranes bounding the mature macrogamete separated from the surface but remained as a veil surrounding the developing oocyst throughout the whole intracellular process. Wall-forming bodies Type I were initially applied to the limiting membrane of the zygote cytoplasm; a layer of material similar to their contents was then formed around the zygote. As this occurred a new double membrane was formed surrounding the oocyst cytoplasm. The outer wall layer was initially homogenous in appearance but later developed into 2 zones, an outer amorphous region and an inner osmiophilic region. The inner layer of the oocyst wall was formed from the contents of the wallforming bodies Type II which dispersed between the outer wall and the limiting membranes of the oocyst cytoplasm. There was evidence of an additional membrane formed external to the outer wall. The outer membranes were not present around the wall of oocysts passed in the faeces of chicks, but the same wall zonation was evident, although the inner osmiophilic zone of the outer wall layer was markedly thinner in comparison with the same zone seen in the tissues.</jats:p