Arbuscular Mycorrhizal Association Contributes to Cr Accumulation and Tolerance in Plants Growing on Cr Contaminated Soils

Arbuscular mycorrhizal (AM) fungi are well known root symbionts in heavy metal polluted soils. To assess AM fungal association and their contribution to the host plants naturally growing on a highly chromium (Cr) contaminated soil, the present study has been undertaken. The soil of the study site was contaminated with 32,562 ppm Cr coming from tannery industry. The study site was dominated by Cynodon dactylon (L.) Pers., Parthenium hysterophorus L., Croton bonplandianum Baill and Prosopis juliflora (Sw.) DC. High mycorrhizal colonization (31–83%) and low spore population (5–11 spores/g) was recorded. The diversity of AM fungi was very low because of stress caused by Cr. Only seven AM fungal isolates have been recovered. Funneliformis mosseae, Rhizophagus intraradices, Funneliformis geosporus and Glomus sinuosum have been recovered from two hosts, while, Rhizophagus fasciculatus, Glomus aggregatum and Acaulospora scrobiculata from single host only. Cr accumulation in the roots were analyzed through AAS and correlated with various mycorrhization parameters. The results of correlation through PCA showed that, various mycorrhization parameters were under strong influence of Cr accumulation in the roots. Furthermore, all the AM fungi showed certain adaptive features like compact sporocarp, thick spore wall, sloughing outermost wall layer and formation of water stable aggregates. Low species diversity, high mycorrhizal colonization, presence of adaptive features and strong correlation of mycorrhizal parameters with the Cr accumulation in the roots clearly indicated that, these AM fungi have contributed to the Cr accumulation and tolerance to the host plants in Cr sludge deposit.

     

Pigmentary disorders in the Mediterranean area

The Mediterranean area represents the area of land that borders the Mediterranean basin. It is composed of several countries that share many geographic and racial characteristics. Although Mediterraneans seem to share common skin type and are subjected to similar enviromental factors, they still represent a genetic and socioeconomic diversity. True prevalence of pigmentary disorders in this area depends on large epidemiologic studies, including countries that are not available. This article, however, highlights and classifies the most important developmental (heritable-genetic) and acquired pigmentary disorders seen and reported in this important area of the world.     

Diabetes-induced renal vascular dysfunction is normalized by inhibition of epidermal growth factor receptor tyrosine kinase

Contribution of receptor tyrosine kinase activation to development of diabetes-induced renal artery dysfunction is not known. We investigated the ability of a chronic administration of genistein, a broad-spectrum inhibitor of tyrosine kinases (TKs), and AG1478, a specific inhibitor of epidermal growth factor receptor (EGFR) TK activity, to modulate the altered vasoreactivity of isolated renal artery ring segments to common vasoconstrictors in streptozotocin-induced diabetes. In diabetic renal artery, the vasoconstrictor responses induced by norepinephrine, endothelin-1 and angiotensin II were significantly increased. Inhibition of TKs or the EGFR pathway did not affect the agonist-induced vasoconstrictor responses in the non-diabetic control animals. However, inhibition of TKs by genistein or EGFR TK by AG1478 treatment produced a significant normalization of the altered agonist-induced vasoconstrictor responses without affecting blood glucose levels. Treatment with diadzein, an inactive analogue of genistein, did not affect the vasoconstrictor responses in the diabetic animals. Western blotting showed that phosphorylated EGFR protein levels were increased in vehicle-treated diabetic animals. In renal arteries from AG1478-treated diabetic animals, EGFR protein levels were similar to non-diabetic control animals. These data suggest that activation of TK-mediated pathways, including the EGFR TK signalling pathway, are involved in the development of diabetic vascular dysfunction in the renal artery.     

Modulating co-stimulation

The modulation of co-stimulatory pathways represents a novel therapeutic strategy to regulate autoimmune diseases. Auto-reactive CD4+ T cells play a critical role in initiating the immune response leading to inflammation and autoimmune diseases. Blocking co-stimulatory signals prevents T-cell activation, thus diminishing autoimmune responses and possibly preventing the progression of autoimmune disease. Blockade of several co-stimulatory pathways has been investigated in animal models and has led to clinical trials testing specific blocking agents in humans. In this review we will describe the role of co-stimulatory pathways, primarily the CD28-B7 pathway, in autoimmune diseases, and we will present in vivo and in vitro studies supporting the efficacy of co-stimulation blockade in animal models of autoimmune disease. Finally, we will discuss the clinical therapeutic efficacy of blocking monoclonal antibodies in preventing or reducing auto-antigen driven T-cell activation in humans with particular attention to the CD28/B7 pathway. Inhibiting co-stimulatory molecule interactions by using monoclonal antibodies seems to be an original approach to regulate autoimmune diseases in humans.     

Shyness and social phobia in Israeli Jewish vs Arab students

Background

Social anxiety disorder (SAD) has been repeatedly shown to be very prevalent in the Western society with prevalence rates of 10% or above. However, very few studies have been performed in the Middle East and in Arab countries.

Methods

A total of 300 Israeli students participated in our study and were administered the Liebowitz Social Anxiety Scale (LSAS), the Cheek and Buss Shyness Questionnaire (CBSQ), and a sociodemographic questionnaire.

Results

A total of 153 Jewish and 147 Arab students participated in the survey. Social anxiety disorder was found in 12.33% of the sample, according to the LSAS cutoff score of more than 60. The 2 subsamples had similar LSAS and CBSQ scores and similar SAD-positive rates (LSAS >60). Females had higher scores on the LSAS, as were those without a spouse and those who had been in psychological treatment. Based on a regression analysis, the significant predictors of the LSAS score were the CBSQ score and female sex. A very high correlation was found between the LSAS and the CBSQ scores.

Conclusions

Although our sample is not representative of the whole Israeli population, we conclude that SAD and shyness were similarly prevalent in Jewish and Arab students in Israel. Social anxiety disorder scores were higher among females, those without a spouse, and those who received psychological treatment. Further studies on the clinical and cultural characteristics of SAD in Israeli subcultures would add to the growing body of knowledge on SAD in various cultures.     

Risk factors for hepatitis C virus infection in male adults in Rawalpindi-Islamabad, Pakistan

OBJECTIVE: To identify risk factors associated with HCV infection in Islamabad-Rawalpindi. METHODS: Fifty-seven cases and 180 controls were enrolled from various departments of the nine major hospitals of the Rawalpindi-Islamabad during July-September 1998. Cases were enzyme-linked immunosorbent assay (ELISA) positive for antibodies to HCV (anti-HCV), aged 20-70 years, and residents of Islamabad or Rawalpindi division. Controls were anti-HCV ELISA negatives of the same age range and from the same area. A structured questionnaire was used to collect data on demographic variables and potential risk factors, which was analysed by logistic regression to calculate crude and adjusted odds ratios (OR) and corresponding 95% confidence intervals (CI) for risk factors. RESULTS: The final multivariate logistic regression model revealed that after adjusting for age, cases were more likely to have received therapeutic injections in the past 10 years (1-10 vs. 0 therapeutic injections; adjusted OR=2.8, 95% CI: 1.1-7.1; > 10 vs. 0 therapeutic injections; adjusted OR=3.1, 95% CI: 1.2-7.9) and were significantly more likely to have daily face (adjusted OR=5.1, 95% CI: 1.5-17.0) and armpit shaves (adjusted OR=2.9, 95% CI: 1.3-6.5) by a barber. CONCLUSION: HCV control and prevention programs in this region should include safe injection practices and educate men about the risk of HCV infection from contaminated instruments used by barbers.     

Drug-induced cholestasis

Recent progress in understanding the molecular mechanisms of bile formation and cholestasis have led to new insights into the pathogenesis of drug-induced cholestasis. This review summarizes their variable clinical presentations, examines the role of transport proteins in hepatic drug clearance and toxicity, and addresses the increasing importance of genetic determinants, as well as practical aspects of diagnosis and management.