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Kommerell’s diverticulum is a rare saccular aneurysmal dilation of the descending aorta. We report a case of a 3.5-year-old boy with the extremely rare combination of Kommerell’s diverticulum with a right descending aorta and proximal patent ductus arteriosus aneurysm forming an incomplete vascular ring. To our knowledge, this rare case has not been reported to date.  相似文献   
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Arsenic (As) is considered to be one of the top environmental contaminants of concern worldwide. In many regions in Pakistan, there are reports of increased levels of As in the environment, and this metalloid remains a major source of contamination of soil, water and fodder. This pathway of exposure has emerged as a new threat for both wildlife and the surrounding human communities because of the mobilization and accumulation of As via the food chain. The objective of this critical review is to synthesize historical information about As levels in the environmental resources of Pakistan to better characterize the risk to livestock and humans in the region. The South Punjab and Sindh are the dominant areas which are reported to contain the highest As contamination compared to other regions. This is a concern as millions of animals as well as the human population are facing significant health issues due to As. For example, some of the population of Sindh province are potentially faced with As levels ~10–50?μg/L in drinking water, which is well above safe drinking limits of 10?μg/L outlined by the World Health Organization. These collective data on As are anticipated to be a useful source of information for decisions by the environmental protection agency in Pakistan regarding the adoption of preventive measures against its adverse impacts and toxicity.  相似文献   
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Context: Azadirachta indica A. Juss. (Meliaceaes) leaves have been used traditionally to treat swelling and rheumatism in Indian cultures.

Objective: To fractionate A. indica leaf extracts using bioactivity guided manner for identification of the active anti-inflammatory principles.

Materials and methods: Polarity-gradient sequential extracts (petroleum ether, chloroform, methanol, and water) of A. indica leaves were screened for their anti-inflammatory potential using the carrageenan-induced rat paw edema model (1?g/kg). The chloroform extract was sequentially fractionated to obtain n-hexane (F-1), n-hexane-chloroform (F-2), and chloroform (F-3) fractions and their inhibitory effect on rat paw edema was evaluated (500?mg/kg). Inhibitory effect of F-2 on granuloma formation, plasma interleukin (IL-1), and tumor necrosis factor (TNF-α) was assessed at the doses of 100, 200, and 400?mg/kg using the cotton pellet assay in rats. Three sub-fractions (SF-1, SF-2, and SF-3) were obtained upon chromatography of F-2, and their inhibitory effect on cyclooxygenase was assessed at 200?µg/mL concentration. The sub-fractions were subjected to gas chromatography–mass spectrometry (GC-MS).

Results: All the extracts showed significant anti-inflammatory effect; however, chloroform extract was the most effective against paw edema (53.25% inhibition). The three fractions of chloroform extract showed significant effect, while F-2 being the most potent (51.02%). F-2 demonstrated dose-dependent inhibition of granuloma and cytokines. Interestingly, all the sub-fractions of F-2 inhibited COX-1 and COX-2 with almost equal potential. GC-MS revealed that chemically the sub-fractions were totally different from each other.

Discussion and conclusion: Anti-inflammatory effect of A. indica is a result of cumulative and synergistic effects of diversified constituents with varying polarities that collectively exert the effect via suppression of cyclo-oxygenases and cytokines (IL-1 and TNF-α).  相似文献   
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