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1.
The yeast Saccharomyces cerevisiae is a useful model for studying the influence of different stress factors on eukaryotic cells. In this work we used the pesticide imidacloprid, in the Confidor formulation, as the stress factor and analyzed its influence on the metabolic activity, proteome and lipid content and composition of Saccharomyces cerevisiae yeast. During the cultivation of yeast, the lowest recommended application dose of Confidor (0.025%, v/v) was added to the growth media and its influence on the mitochondria, cytosol with microsomes, and the whole yeast cells was monitored. The results show that under the stress provoked by the toxic effects of Confidor, yeast cells density significantly decreased and the percentage of metabolically disturbed cells significantly increased comparing with untreated control. Also, there was a downregulation of majority of glycolytic, gluconeogenesis, and TCA cycle enzymes (Fba1, Adh1, Hxk2, Tal1, Tdh1,Tdh3, Eno1) thus providing enough acetyl‐CoA for the lipid restructuring and accumulation mechanism since we have found the changes in the cell and mitochondrial lipid content and FA composition. This data suggest that lipids could be the molecules that orchestrate the answer of the cells in the stress response to the Confidor treatment.  相似文献   
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Monoclonal antibodies were used in an inhibition enzymelinked immunosorbent assay (IELISA) to detect a variety of schistosome derived antigens. Preparations were obtained from various stages ofSchistosoma mansoni and from the eggs ofS. japonicum. Using appropriate titers of monoclonal antibodies it was possible to detect less than 0.01 g/ml of schistosome antigens. The sensitivity of IELISA was dependent upon the type and concentration of the monoclonal antibody used, as well as upon the source of the antigens. Specificity studies showed that some of the monoclonal antibodies recognized species specific antigenic determinants, while others reacted against genus specific antigens. Furthermore, certain antibodies interacted with antigens which were neither genus or species specific. Fractions ofS. mansoni andS. japonicum egg antigen extracts, which have been previously considered to be relatively pure, were compared using certain monoclonal antibodies. The results indicate that these fractions are very heterogenous with regard to the unique antigenic specificities. For example, most antigenic determinants in crude soluble egg antigen are not retained on concanavalin-A lectin affinity columns and major serologic antigens have more than one determinant with different distributions. The expression of these antigenic determinants appears to be a function of both the concentration of the specific antigen and the mode of expression of the moiety within the antigenic matrix.  相似文献   
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Schrander-Stumpel C, de Die-Smulders C, de Krom M, Schyns-Fleuren S, Hamel B, Jaeken D, Fryns J-P. Marden-Walker syndrome: case report, literature review and nosologic discussion.
Clin Genet 1993: 43: 303–308. © Munksgaard, 1993
The Marden-Walker syndrome is characterized by psychomotor retardation, a mask-like face with blepharophimosis, micrognathia and a high-arched or cleft palate, low-set ears, kyphoscoliosis and joint contractures. We report on a male patient with the clinical features of the syndrome. In addition, he had a Dandy-Walker malformation with hydrocephalus and vertebral abnormalities. During pregnancy, there were feeble fetal movements and polyhydramnios. We propose that Marden-Walker syndrome is one of the etiologic possibilities in children with the heterogeneous fetal a(hypo)kinesia deformation sequence (FADS). Differential diagnosis is discussed. The etiology is probably heterogeneous.  相似文献   
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In this final of a 5-part Focus Seminar series on precision medicine, we focus on catecholaminergic polymorphic ventricular tachycardia (CPVT). This focus on CPVT allows us to take a “deep dive” and explore the full extent of the precision medicine opportunities for a single cardiovascular condition at a level that was not possible in the preceding articles. As a new paradigm presented in this article, it has become clear that CPVT can occur as either a typical or atypical form. Although there is a degree of overlap between the typical and atypical forms, it is notable that they arise due to different underlying genetic changes, likely exhibiting differing mechanisms of action, and presenting with different phenotypic features. The recognition of these differing forms of CPVT and their different etiologies and mechanisms is an important step toward implementing rapidly emerging precision medicine approaches that will tailor novel therapies to specific gene defects.  相似文献   
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Graefe's Archive for Clinical and Experimental Ophthalmology - To investigate retinal changes in β-thalassemia major patients and identify their association with systemic risk factors. In...  相似文献   
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BackgroundAgeing is characterized by a decline in cognitive and bodily functions. Metformin, the most commonly prescribed antidiabetic agent today, has proved to be able to modulate oxidative stress, several inflammatory pathways and cellular senescence to promote anti-ageing. This review aims to explore and summarize the effects of metformin on ageing.ResultsMetformin, a longstanding treatment for diabetes, has been shown to increase lifespan in both vertebrate and mammalian models. This pleiotropic effect is hypothesized to mimic calorie restriction, a currently proven means of slowing ageing, by decreasing insulin and insulin-like growth factor (IGF)-1 levels and improving insulin sensitivity. However, studies have shown that metformin is also able to target several other ageing pathways, thereby inhibiting mammalian target of rapamycin (mTOR), increasing AMPK activity and improving DNA repair. Clinical studies, such as those supported by the UK Clinical Practice Research Datalink service, have reported that diabetes patients treated with metformin live longer than patients without diabetes. Metformin use can also reduce type 2 diabetes mellitus (T2DM) incidence among those at risk, lower cancer incidence, and improve cognitive function, cardiovascular disease (CVD) risk factors and atherosclerosis.ConclusionVarious studies have found that metformin can target several nutrient-sensing, anti-ageing and immune pathways, leading to reductions in oxidative stress, inflammation and DNA damage as well as providing effects similar to those of calorie restriction. However, further trials are still needed to confirm these findings.  相似文献   
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Eristostatin, an RGD-containing disintegrin isolated from the venom of Eristicophis macmahoni, inhibits lung or liver colonization of melanoma cells in a mouse model. In this study, transwell migration and in vitro wound closure assays were used to determine the effect of eristostatin on the migration of melanoma cells. Eristostatin significantly impaired the migration of five human melanoma cell lines. Furthermore, it specifically inhibited cell migration on fibronectin in a concentration-dependent manner, but not that on collagen IV or laminin. In contrast, eristostatin was found to have no effect on cell proliferation or angiogenesis. These results indicate that the interaction between eristostatin and melanoma cells may involve fibronectin-binding integrins that mediate cell migration. Mutations to alanine of seven residues within the RGD loop of eristostatin and four residues outside the RGD loop of eristostatin resulted in significantly less potency in both platelet aggregation and wound closure assays. For six of the mutations, however, decreased activity was found only in the latter assay. We conclude that a different mechanism and/or integrin is involved in these two cell activities.  相似文献   
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