Effects of lipopolysaccharide on the radiation-induced changes in the blood-brain barrier and the astrocytes

The use of radiation to improve the efficacy of chemotherapy on malignant brain tumors is also known to cause side effects on vascular endothelial cells and astrocytes in normal parts of the brain. We investigated the effects of lipopolysaccharide (LPS) on the functional and structural properties of blood-brain barrier (BBB) and the activity of astrocytes during whole-brain irradiation in rats. The permeability of the BBB to Evans blue (EB) dye significantly increased in the cerebral cortex, diencephalon and cerebellum regions of rats exposed to irradiation (P<0.01). In contrast, the BBB permeability in irradiated rats was significantly reduced by LPS (P<0.05). Tumor necrosis factor-alpha (TNF-alpha) levels were increased following LPS, irradiation and irradiation plus LPS (P<0.05, P<0.01). Irradiated brain vessels showed a considerable loss of staining intensity of tight junction proteins Zonula occludens-1 (ZO-1) and occludin. Staining for Zonula occludens-1 and occludin was intensive in animals treated with LPS and irradiation plus LPS. Glial fibrillary acidic protein (GFAP) immunoreactivity was seen in very few astrocytes of irradiated brains. However, this staining showed an increased positive intensity in the brain sections of LPS-treated as well as of irradiation plus LPS-treated animals. These results indicate that LPS reduces the passage of exogenous vascular tracer EB-binding albumin into the brain, at least partly, by increasing the expression of tight junction proteins and GFAP, following the irradiation. We suggest that irradiation may affect paracellular permeability through disruption of tight junction proteins, Zonula occludens-1 and occludin, and LPS could provide beneficial effects on the BBB integrity and the astrocytes against irradiation damage.     

The regional cerebral blood flow changes in major depressive disorder with and without psychotic features

Depressive patients with psychotic features demonstrate distinct biological abnormalities in the hypothalamic-pituitary-adrenal axis (HPA), dopaminergic activity, electroencephalogram sleep profiles and measures of serotonergic function when compared to nonpsychotic depressive patients. However, very few functional neuroimaging studies were specifically designed for studying the effects of psychotic features on neuroimaging findings in depressed patients. The objective of the present study was to compare brain Single Photon Emission Tomography (SPECT) images in a group of unmedicated depressive patients with and without psychotic features. Twenty-eight patients who fully met DSM-IV criteria for major depressive disorder (MDD, 12 had psychotic features) were included in the study. They were compared with 16 control subjects matched for age, gender and education. Both psychotic and nonpsychotic depressed patients showed significantly lower regional cerebral blood flow (rCBF) values in the left and right superior frontal cortex, and left anterior cingulate cortex compared to those of controls. In comparison with depressive patients without psychotic features (DwoPF), depressive patients with psychotic features (DwPF) showed significantly lower rCBF perfusion ratios in left parietal cortex, left cerebellum but had higher rCBF perfusion ratio in the left inferior frontal cortex and caudate nucleus. The present study showed that DwPF have a different rCBF pattern compared to patients without psychotic features. Abnormalities involving inferior frontal cortex, striatum and cerebellum may play an important role in the generation of psychotic symptoms in depression.     

The role of N-acetylcysteine treatment on anti-oxidative status in patients with type II diabetes mellitus

The development of diabetic complications has usually been attributed to the nonenzymic glycation of tissue proteins. Only recently, however, have researchers examined the possible role on free radicals in the pathogenesis of diabetes. In the present study, glutathione (GSH) and major antioxidant enzyme levels in plasma of patients with type II diabetes mellitus were assessed both before and after 3 months of N-acetylcysteine (NAC) therapy. Thirty-two diabetic patients were examined as well as fifteen healthy controls. Before treatment with NAC, glutathione peroxidase (GPx), catalase (CAT), and (GSH) levels of diabetic patients and control subjects showed no significant differences, whereas glutathione S-transferase (GST) levels were higher in type II diabetic patients. Following 3 months of Following NAC supplementation, GSH, GST, and CAT levels were found to be similar to the levels before treatment. On the other hand, GPx activity was significantly lower compared with the values before treatment. According to this finding, NAC treatment could have a positive effect on GPx values in type II diabetic patients showing abnormally high values.     

The effect of cetirizine on sulfidoleukotriene production by blood leukocytes in children with allergic rhinitis

Twelve children with allergic rhinitis due to monosensitivity to Dermatophagoides pteronyssinus (Dp) took part in a placebo-controlled, double-blind, crossover study to evaluate the effect of cetirizine, a second-generation, nonsedating H₁-blocker-type antihistamine, on sulfidoleukotriene releasability by blood leukocytes and to determine its correlation with clinical findings and nasal challenge scores. Sulfidoleukotriene release by blood leukocytes was determined by the cellular allergen stimulation test (CAST), which measures leukotriene (LT)C₄, LTD₄, and LTE₄, all in one assay. Compared to placebo, cetirizine significantly ( P ≤0.05) decreased daily symptom scores of nasal discharge, nasal itching, and sneezing, as well as the number of sneezings after nasal challenge with the antigen, without alleviating nasal obstruction ( P ≥0.05). It also suppressed both early ( P ≤0.05) and late skin reactions to intradermal tests. Although cetirizine did not influence in vitro sulfidoleukotriene production by blood leukocytes with buffer or anti-IgE ( P ≥0.05), it substantially reduced the release of these mediators upon challenge with Dp antigen. Furthermore, there was a high correlation between the number of sneezes after challenge and the amount of sulfidoleukotriene released in nine patients ( r =0.78; P ≤0.01). It is concluded that the amount of sulfidoleukotrienes produced by blood leukocytes in vitro may reflect the nasal hyperreactivity of the patient, and that cetirizine, which is highly effective in the treatment of allergic rhinitis, owes part of its effect to inhibition of sulfidoleukotriene releasability by blood leukocytes in children.     

Do Ramadan fasting restrictions alter eating behaviours?

During Ramadan month, Muslims should refrain from drinking, eating and smoking from dawn to sunset. Ramadan fasting can be considered as a kind of dietary restriction. Eating restriction is a risk factor for later development of eating disorders. The purpose of this study is to evaluate whether Ramadan fasting changes the eating behaviours of young people, especially girls who are known as the most vulnerable group for eating disorders. Our sample consisted of 79 healthy volunteers from a high school (63 females; mean age = 16.29; 16 males; mean age = 16.31) who fasted during the Ramadan month. No statistically significant differences were found between the scores of EAT (Eating Attitude Test) and BITE (Bulimic Investigatory Test, Edinburgh) which were administered within the weeks before and after Ramadan. According to our results Ramadan fasting restrictions do not seem to change the eating behaviours of young girls and boys. Copyright © 2008 John Wiley & Sons, Ltd and Eating Disorders Association.     

SEN virus prevalence among non-B and non-C hepatitis patients with high liver function tests in the south of Turkey

We investigated the characteristics and detection rates of SEN virus (SENV) infection among 100 Turkish patients who had with high alanine aminotransferase (ALT) and aspartate aminotransferase levels but were negative for HBV DNA and HCV RNA and had no history of transfusion. As a control group, we also analyzed 50 healthy individuals who had normal ALT levels, were negative for HBV DNA and HCV RNA, and had no history of transfusion. The serum samples of patient and controls were analyzed by PCR to detect the presence of SENV DNA and its two genotypes (SENV-H and SENV-D). We detected SENV DNA in 13 of 100 (13%) patients. Five of 13 (38.46%) patients were positive for SENV-D and 8 of 13 (61.53%) patients were positive for SENV-H DNA. We also detected SENV DNA in 5 of 50 (10%) patients in the control group. Two of 5 (40%) patients were positive for SENV-D and 3 of 5 (60%) patients were positive for SENV-H DNA in the control group. SENV was detected at almost the same frequency in the patient and control group. SENV did not seem to contribute to the pathogenesis of liver disease (P > 0.05) in this cohort. Our results also showed that SENV transmission was not only associated with blood transfusion but also with some other possible routes.     

Cardiac T2* MRI assessment in patients with thalassaemia major and its effect on the preference of chelation therapy

The aim of the study is to assess the relationship between T2* magnetic resonance imaging (MRI) values and age, serum ferritin level, left ventricular ejection fraction (LVEF), splenectomy status, and to identify appropriate modifications to chelation therapy based on T2* MRI results of children with thalassaemia major. Sixty-four patients with thalassaemia major (37 girls/27 boys) older than 8 years of age were enrolled in the study. Based on the first T2* MRI, the patients’ myocardial iron depositions were classified into three groups: T2* MRI <10 ms (high risk group), T2* MRI 10–20 ms (medium-risk group) and T2* MRI >20 ms (low-risk group). There was no significant relationship between T2* MRI value and ages, serum ferritin levels and splenectomy status of thalassaemia major patients. The mean LVEFs were 60, 75, and 72.5 % in the high-, medium-, and low-risk groups, respectively (P = 0.006). The mean cardiac iron concentrations calculated from the T2* MRI values were 4.96 ± 1.93, 1.65 ± 0.37, and 0.81 ± 0.27 mg/g in the high-, medium-, and low-risk groups, respectively. Chelation therapies were re-designed in 24 (37.5 %) patients according to cardiac risk as assessed by cardiac T2* MRI. In conclusion, until recently, T2* MRI has been employed to demonstrate cardiac siderosis without a direct relationship with the markers used in follow-up of patients with thalassaemia. However, modifications of chelation therapies could reliably be planned according to severity of iron load displayed by T2* MRI.     

Comparison of the efficacy of combination and monotherapy with caspofungin and liposomal amphotericin B against invasive candidiasis

OBJECTIVE: To investigate if combination therapy with liposomal amphotericin B (LAmB), and caspofungin (CAS) is superior to monotherapies in an experimental model with azole-resistant Candida albicans. METHODS: This study was carried out between October 2006 and August 2007 in Celal Bayar University, Manisa, Turkey. A total of 144 mice were included in the study, and divided into 4 groups as: control (n=36), CAS treatment group n=36, LAmB treatment group (n=36), and combination therapy group (n=36). Treatment efficacy was assessed by determining survival, as well as, the decrease in tissue fungal densities. RESULTS: The fungal densities in tissues were significantly reduced, and the survival rates were prolonged with either CAS only, or LAmB only, or with combination therapy compared to those of controls (p<0.05). There was no significant difference between monotherapy groups. Decrease in tissue fungal densities were significant in CAS and LAmB (1mg/kg) combination group, compared to CAS (1mg/kg) and LAmB (1mg/kg) groups (p=0.004 for CAS, p=0.009 for LAmB). Survival rates were similar in both treatment groups. CONCLUSION: The combination treatment was superior with 1mg/kg of doses of LAmB and CAS in terms of reducing the tissue fungal burden. Although with combination therapy the survival rates prolonged in all subgroups, no significant difference between the combination and monotherapies could be shown. Additional studies with a large number of cases are warranted to investigate the superiority of combination therapy.