[Leptin and autoimmune diseases]

Introduction: Leptin, an anti-obesity hormone, is also a regulator of the immune response which sends important signals regarding the metabolic status and immune system function. This hormone/cytokine can affect the secretion of acute phase proteins such as Interleukin-1 and TNF- alpha and facilitate communication between nutrition and Th1 immune response so that when the food intake reduces, plasma leptin levels decreases, leading to reduced function of the immune system. Increase in blood leptin levels in obesity makes the obese people more susceptible to cardiovascular diseases, autoimmune diseases and cancer. Previous researches demonstrate the important effects of leptin in metabolism, whereas more recent studies show that this molecule has an important role in many other key functions of body such as haematopoiesis, thermogenesis, reproduction, angiogenesis, homeostasis and immune system. This paper aims to review the most recent findings regarding the role of leptin in the pathology of autoimmune disease, in particular multiple sclerosis, psoriasis, autoimmune thyroid disease, lupus erythematosus, endometriosis and rheumatoid arthritis

[ investigation of molecular epidemiology of Shigella soneii isolated from clinical cases in Tehran using RAPD-PCR method]

Bloody diarrhea [Shigellosis] is caused by different species of Shigella and is often seen in children befor than under 15 years old must be aded. less than 15 years of age. This disease is extremely contagious, epidemic and endemic in communities with low level hygiene and in majority of cases is accompanied with hemolytic uremia syndrome and decreased children's growth. As the rate of infection by Shigella soneii among different ranges of age is considered as an indicator of hygiene level, this study was designed to detect the rate of infection by Shigella soneii among different ranges of ages in Tehran by Random Amplified Polymorphic DNA [RAPD-PCR] between 2002-2006. In this study totally 60 isolates of Shigella soneii taken from 36 [60%] boys and 24 [40%] girls were studied. All isolates were primary confirmed as Shigella species by biochemical [Motility, MR, Citrate, H[2]S, Indole, Lysin decarboxylase, Ornitin decarboxylase, ONPG] and serologic tests; then all isolates were finally confirmed as Shigella soneii by Random Amplified Polymorphic DNA [RAPD-PCR] test. Among all 60 patients, the highest rate of infection with Shigella soneii belonged to 1-2 year-old group [36/7%]. Furthermore, the lowest rate of infection belonged to group with more than 9 years of age [1/6%]. This study showed that RAPD PCR method had a relative good discrimination power, and was a good method for typing of Shigella isolates in molecular epidemiological studies according to its high discrimination power, typing ability, reproducibility, low cost, rapidity and easy of use