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Summary:  Mast cells are well known for their involvement in allergic and anaphylactic reactions, during which immunoglobulin E (IgE) receptor (FcɛRI) aggregation leads to exocytosis of the content of secretory granules (1000 nm), commonly known as degranulation, and secretion of multiple mediators. Recent findings implicate mast cells also in inflammatory diseases, such as multiple sclerosis, where mast cells appear to be intact by light microscopy. Mast cells can be activated by bacterial or viral antigens, cytokines, growth factors, and hormones, leading to differential release of distinct mediators without degranulation. This process appears to involve de novo synthesis of mediators, such as interleukin-6 and vascular endothelial growth factor, with release through secretory vesicles (50 nm), similar to those in synaptic transmission. Moreover, the signal transduction steps necessary for this process appear to be largely distinct from those known in FcɛRI-dependent degranulation. How these differential mast cell responses are controlled is still unresolved. No clinically available pharmacological agents can inhibit either degranulation or mast cell mediator release. Understanding this process could help develop mast cell inhibitors of selective mediator release with novel therapeutic applications.  相似文献   
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Introduction and objective

The role of metformin in gestational diabetes mellitus (GDM) is also increasing. However, almost half of metformin-treated women required additional insulin. Therefore, identifying the characteristics of these women may help define optimal therapeutic strategy.

Methods

This is a retrospective cohort study done in a District General Hospital, UK. GDM was diagnosed by 75?g OGTT test between 24 and 28 weeks of gestation with fasting levels of ≥6.1?mmol/l and/or 2?h postprandial (PP) level of ≥7.8?mmol/l. Logistic regression and receiver operator curves (ROC) were performed to identify the predictors of metformin failure.

Results

Out of 228 women with GDM included, 46/228 (20.2%) and 151/228 (66.2%) received insulin and metformin as first-line medication respectively. Among the metformin-treated, 13 stopped treatment and were excluded from analysis. Of the included 138 metformin-treated women, 77 (55.8%) required supplementary insulin (metformin failure). Metformin failure group had higher maternal age and fasting glucose level at OGTT, HbA1c at OGTT and earlier gestational age (GA) at medication initiation. Metformin failure was predicted if fasting OGTT level >4.8?mmol/l (69% sensitivity and 62% specificity). If the fasting levels of IADPSG (International Association of Diabetes and Pregnancy Study Groups) criteria and NICE (National Institute of Health and Care Excellence) were used, the positive predictive value was 78% and 77% respectively.

Conclusion

As women with higher fasting glucose levels have higher chance of necessitating insulin in later pregnancies, appropriate addition of insulin at metformin initiation for these women could help better glycaemic control throughout pregnancy.  相似文献   
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The aim of the present study was to develop a probioticated cucumber juice by optimizing the concentration of prebiotic (inulin), stevia (Stevia rebudiana) and inoculum (Lactobacillus plantarum) by varying one factor at a time. Cucumber juice with 2% prebiotic had a pH 3.76, acidity 0.239%, total sugars 198.2 μg/mL, reducing sugars 102.3 μg/mL and microbial viability of 1.36 × 108 colony forming units (CFU)/mL, respectively. The juice with 3% stevia had a pH 3.59, acidity 0.388%, total sugars 214 μg/mL, reducing sugars 156.7 μg/mL and microbial viability of 6.7 × 107 CFU/mL, respectively. The juice with 3% inoculum size had a pH 3.82, acidity 0.39%, total sugars 128.3 μg/mL, reducing sugars 198.6 μg/mL and microbial viability of 3.5 × 108 CFU/mL, respectively. Maximum growth of the probiotic (L. plantarum) in the cucumber juice was obtained at the end of 48 h of fermentation for 2% prebiotic, 3% stevia and 3% inoculum size without much changes in nutritional and organoleptic properties. The probiotic strain namely L. plantarum proved its ability and suitability to ferment cucumber juice. The growth of the probiotic in the cucumber juice was found maximum with 2% prebiotic, 3% stevia and 3% inoculum size at the end of 48 h of fermentation with minimal changes in nutritional value and organoleptic characteristics with a good shelf life at 4 °C in polyethylene terephthalate bottles.  相似文献   
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The recommended operative management of unruptured sinus of Valsalva aneurysm consists of closure of the mouth of the aneurysm with or without aortic valve surgery. We report a case of unruptured aneurysm producing right ventricular outflow tract obstruction. Closure of the mouth of the aneurysm failed to relieve the obstruction, which was subsequently achieved by excising the aneurysmal wall overlying the outflow tract.  相似文献   
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Proceedings of the National Academy of Sciences, India Section B: Biological Sciences - L-asparaginase (ASNase), a tetrameric enzyme, holds comprehensive applications in food industries as a...  相似文献   
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Stress is one of the most frequently self‐identified seizure triggers in patients with epilepsy; however, most previous publications on stress and epilepsy have focused on the role of stress in the initial development of epilepsy. This narrative review explores the causal role of stress in triggering seizures in patients with existing epilepsy. Findings from human studies of psychological stress, as well as of physiologic stress responses in humans and animals, and evidence from nonpharmacologic interventions for epilepsy are considered. The evidence from human studies for stress as a trigger of epileptic seizures is inconclusive. Although retrospective self‐report studies show that stress is the most common patient‐perceived seizure precipitant, prospective studies have yielded mixed results and studies of life events suggest that stressful experiences only trigger seizures in certain individuals. There is limited evidence suggesting that autonomic arousal can precede seizures. Interventions designed to improve coping with stress reduce seizures in some individuals. Studies of physiologic stress using animal epilepsy models provide more convincing evidence. Exposure to exogenous and endogenous stress mediators has been found to increase epileptic activity in the brain and trigger overt seizures, especially after repeated exposure. In conclusion, stress is likely to exacerbate the susceptibility to epileptic seizures in a subgroup of individuals with epilepsy and may play a role in triggering “spontaneous” seizures. However, there is currently no strong evidence for a close link between stress and seizures in the majority of people with epilepsy, although animal research suggests that such links are likely. Further research is needed into the relationship between stress and seizures and into interventions designed to reduce perceived stress and improve quality of life with epilepsy.  相似文献   
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