In mammals, changing day length modulates endocrine rhythms via nocturnal melatonin secretion. Studies of the pituitary pars tuberalis (PT) suggest that melatonin-regulated clock gene expression is critical to this process. Here, we considered whether clock gene rhythms continue in the PT in the absence of melatonin and whether the effects of melatonin on the expression of these genes are tempo...

Abstract Background The human circadian clock is present in cells throughout the body. It consists of CLOCK and BMAL1 that heterodimerize bind to E-box sequences mediate transcription a large number genes, including Periods (PERs) Cryptochromes (CRYs). PERs CRYs constitute part negative feedback loop inhibit CLOCK:BMAL1-mediated transcription. Recently, we have shown patients with active ulcera...

P roper circadian clock function is essential for the coordination of cellular functions within an organism in response to light and dark cycles. Although epidemiological studies have linked altered circadian rhythms to cancer susceptibility (1, 2), the molecular mechanisms tying the circadian clock to cancer are poorly understood. In PNAS, Lee and Sancar (3) demonstrate that loss of the core c...

OBESITY HAS BECOME a serious and growing public health problem (27). Attempts to develop new therapeutic strategies have focused mostly on energy expenditure and caloric intake. Recent studies link energy homeostasis to the circadian clock at the behavioral, physiological, and molecular levels (7, 17, 25). In fact, most aspects of physiology, including sleep-wake cycles, cardiovascular activity...

background: the mammalian ovary is controlled by a number of biological rhythms, which regulate the recruitment and release of mature oocytes. the main objective of this study was to investigate the role of cellular clock proteins during follicle maturation in the mouse estrous ovary. methods: immunohistochemical (ihc) studies were performed on ovaries from 50 estrous staged mice culled at two ...

وراثت مقاومت سفیدبالک گلخانه، Trialeurodes vaporariorum Westwood (Hemiptera: Aleyrodidae)، به دو ترکیب ایمیداکلوپرید و کلرپایریفوس مورد مطالعه قرار گرفت. در این پژوهش، از جمعیت فیلستان ورامین (FL) عنوان والد مقاوم فردیس کرج (FR) حساس استفاده شد. مقدار ترتیب حدودا 62/13 91/14 برابر بود. عدم وجود اختلاف معنی‌دار LC50 روی تلاقی‌های F1 (R♂×S♀) Fʹ1 (R♀×S♂) نشان داد که T. نوع اتوزومی (غیرجنسی) است. ه...