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51.
A virus recovered by inoculation of sap from Austrian vines with yellow mosaic symptoms was compared with, and found virtually indistinguishable from, an authentic Hungarian isolate of grapevine chrome mosaic nepovirus. This seems to be the first record of the virus in Austria.  相似文献   
52.
Laboratory experiments using whole cobs were conducted to examine the effect of varying densities of the larger grain borer, Prostephanus truncatus and the maize weevil, Sitophilus zeamais on rate of population increase by the histerid beetle, Teretriosoma nigrescens , a predator primarily of P. truncatus . Densities of all species of insects were determined at the end of the experiment, and an electrophoretic analysis of gut content was conducted on larval and adult T. nigrescens sampled during the experiments. Results indicated that T. nigrescens has a strong preference for P. truncatus and densities of T. nigrescens were associated only with densities of P. truncatus . The maize weevil played little role as an alternative prey or in interfering with T. nigrescens reproduction.  相似文献   
53.
Inflammatory bowel diseases (IBD) is the result of dysregulation of mucosal innate and adaptive immune responses. Factors such as genetic, microbial and environmental are involved in the development of these disorders. Accordingly, animal models that mimic human diseases are tools for the understanding the immunological processes of the IBD as well as to evaluate new therapeutic strategies. Crotoxin (CTX) is the main component of Crotalus durissus terrificus snake venom and has an immunomodulatory effect. Thus, we aimed to evaluate the modulatory effect of CTX in a murine model of colitis induced by 2,4,6- trinitrobenzene sulfonic acid (TNBS). The CTX was administered intraperitoneally 18 hours after the TNBS intrarectal instillation in BALB/c mice. The CTX administration resulted in decreased weight loss, disease activity index (DAI), macroscopic tissue damage, histopathological score and myeloperoxidase (MPO) activity analyzed after 4 days of acute TNBS colitis. Furthermore, the levels of TNF-α, IL-1β and IL-6 were lower in colon tissue homogenates of TNBS-mice that received the CTX when compared with untreated TNBS mice. The analysis of distinct cell populations obtained from the intestinal lamina propria showed that CTX reduced the number of group 3 innate lymphoid cells (ILC3) and Th17 population; CTX decreased IL-17 secretion but did not alter the frequency of CD4+Tbet+ T cells induced by TNBS instillation in mice. In contrast, increased CD4+FoxP3+ cell population as well as secretion of TGF-β, prostaglandin E2 (PGE2) and lipoxin A4 (LXA4) was observed in TNBS-colitis mice treated with CTX compared with untreated TNBS-colitis mice. In conclusion, the CTX is able to modulate the intestinal acute inflammatory response induced by TNBS, resulting in the improvement of clinical status of the mice. This effect of CTX is complex and involves the suppression of the pro-inflammatory environment elicited by intrarectal instillation of TNBS due to the induction of a local anti-inflammatory profile in mice.  相似文献   
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55.
Ranolazine, an anti-anginal drug, is a late Na(+) channel current blocker that is also believed to attenuate fatty acid oxidation and mitochondrial respiratory complex I activity, especially during ischemia. In this study, we investigated if ranolazine's protective effect against cardiac ischemia/reperfusion (IR) injury is mediated at the mitochondrial level and specifically if respiratory complex I (NADH Ubiquinone oxidoreductase) function is protected. We treated isolated and perfused guinea pig hearts with ranolazine just before 30 min ischemia and then isolated cardiac mitochondria at the end of 30 min ischemia and/or 30 min ischemia followed by 10 min reperfusion. We utilized spectrophotometric and histochemical techniques to assay complex I activity, Western blot analysis for complex I subunit NDUFA9, electron paramagnetic resonance for activity of complex I Fe-S clusters, enzyme linked immuno sorbent assay (ELISA) for determination of protein acetylation, native gel histochemical staining for respiratory supercomplex assemblies, and high pressure liquid chromatography for cardiolipin integrity; cardiac function was measured during IR. Ranolazine treated hearts showed higher complex I activity and greater detectable complex I protein levels compared to untreated IR hearts. Ranolazine treatment also led to more normalized electron transfer via Fe-S centers, supercomplex assembly and cardiolipin integrity. These improvements in complex I structure and function with ranolazine were associated with improved cardiac function after IR. However, these protective effects of ranolazine are not mediated by a direct action on mitochondria, but rather indirectly via cytosolic mechanisms that lead to less oxidation and better structural integrity of complex I.  相似文献   
56.
There is strong evidence that vasodilatory nitric oxide (NO) donors have anabolic effects on bone in humans. Parathyroid hormone (PTH), the only osteoanabolic drug currently approved, is also a vasodilator. We investigated whether the NO synthase inhibitor L‐NAME might alter the effect of PTH on bone by blocking its vasodilatory effect. BALB/c mice received 28 daily injections of PTH[1–34] (80 µg/kg/day) or L‐NAME (30 mg/kg/day), alone or in combination. Hindlimb blood perfusion was measured by laser Doppler imaging. Bone architecture, turnover and mechanical properties in the femur were analysed respectively by micro‐CT, histomorphometry and three‐point bending. PTH increased hindlimb blood flow by >30% within 10 min of injection (P < 0.001). Co‐treatment with L‐NAME blocked the action of PTH on blood flow, whereas L‐NAME alone had no effect. PTH treatment increased femoral cortical bone volume and formation rate by 20% and 110%, respectively (P < 0.001). PTH had no effect on trabecular bone volume in the femoral metaphysis although trabecular thickness and number were increased and decreased by 25%, respectively. Co‐treatment with L‐NAME restricted the PTH‐stimulated increase in cortical bone formation but had no clear‐cut effects in trabecular bone. Co‐treatment with L‐NAME did not affect the mechanical strength in femurs induced by iPTH. These results suggest that NO‐mediated vasorelaxation plays partly a role in the anabolic action of PTH on cortical bone. © 2016 The Authors. Cell Biochemistry and Function published by John Wiley & Sons, Ltd.  相似文献   
57.
为实现田间土壤棉花黄萎病菌的早期检测,建立了土壤中棉花黄萎病菌的SYBR Green I荧光定量PCR检测方法。以含342bp PCR扩增产物的阳性质粒为参考,构建了标准曲线,并对该曲线的特异性、敏感性、可重复性进行了评价。结果表明,该方法具有快速、特异性强、敏感度高等特点。检测范围在3.8×103-3.8×108copies/μL之间有良好的线性关系,相关系数R2为0.996,扩增效率为101.5%,灵敏度比常规PCR方法高102倍。  相似文献   
58.
The VPH/Physiome Project is developing the model encoding standards CellML (cellml.org) and FieldML (fieldml.org) as well as web-accessible model repositories based on these standards (models.physiome.org). Freely available open source computational modelling software is also being developed to solve the partial differential equations described by the models and to visualise results. The OpenCMISS code (opencmiss.org), described here, has been developed by the authors over the last six years to replace the CMISS code that has supported a number of organ system Physiome projects.OpenCMISS is designed to encompass multiple sets of physical equations and to link subcellular and tissue-level biophysical processes into organ-level processes. In the Heart Physiome project, for example, the large deformation mechanics of the myocardial wall need to be coupled to both ventricular flow and embedded coronary flow, and the reaction-diffusion equations that govern the propagation of electrical waves through myocardial tissue need to be coupled with equations that describe the ion channel currents that flow through the cardiac cell membranes.In this paper we discuss the design principles and distributed memory architecture behind the OpenCMISS code. We also discuss the design of the interfaces that link the sets of physical equations across common boundaries (such as fluid-structure coupling), or between spatial fields over the same domain (such as coupled electromechanics), and the concepts behind CellML and FieldML that are embodied in the OpenCMISS data structures. We show how all of these provide a flexible infrastructure for combining models developed across the VPH/Physiome community.  相似文献   
59.
Focal and segmental glomerulosclerosis (FSGS) is one of the most important renal diseases related to end-stage renal failure. Bradykinin has been implicated in the pathogenesis of renal inflammation, whereas the role of its receptor 2 (B2RBK; also known as BDKRB2) in FSGS has not been studied. FSGS was induced in wild-type and B2RBK-knockout mice by a single intravenous injection of Adriamycin (ADM). In order to further modulate the kinin receptors, the animals were also treated with the B2RBK antagonist HOE-140 and the B1RBK antagonist DALBK. Here, we show that the blockage of B2RBK with HOE-140 protects mice from the development of FSGS, including podocyte foot process effacement and the re-establishment of slit-diaphragm-related proteins. However, B2RBK-knockout mice were not protected from FSGS. These opposite results were due to B1RBK expression. B1RBK was upregulated after the injection of ADM and this upregulation was exacerbated in B2RBK-knockout animals. Furthermore, treatment with HOE-140 downregulated the B1RBK receptor. The blockage of B1RBK in B2RBK-knockout animals promoted FSGS regression, with a less-inflammatory phenotype. These results indicate a deleterious role of both kinin receptors in an FSGS model and suggest a possible cross-talk between them in the progression of disease.KEY WORDS: Focal and segmental glomerulosclerosis, Bradykinin receptors, Inflammation, Podocyte, Fibrosis  相似文献   
60.
Nephrotoxicity is substantial side effect for 30% of patients undergoing cancer therapy with cisplatin and may force them to change or even abandon the treatment. Studies regarding aerobic exercise have shown its efficacy for the treatment of many types of diseases and its capacity to reduce tumors. However, little is known about the impact of physical exercise on cisplatin-induced acute kidney injury (AKI). In the present study, our aim was to investigate the role of physical exercise in AKI induced by cisplatin. We submitted C57Bl6 male mice to seven weeks of chronic exercise on a training treadmill and treated them with single i.p. injection of cisplatin (20 mg/kg) in the last week. Exercise efficacy was confirmed by an increased capillary-to-fiber ratio in the gastrocnemius muscle of exercised groups (EX and CIS-EX). The group submitted to exercise before cisplatin administration (CIS-EX) exhibited less weight loss and decreased serum urea levels compared to the cisplatin group (CIS). Exercise also showed a protective role against cisplatin-induced cell death in the kidney. The CIS-EX group showed a lower inflammatory response, with less TNF and IL-10 expression in the kidney and serum. In the same group, we observed an increase of IL-6 and HO-1 expression in the kidney. Taken together, our results indicate that chronic aerobic exercise is able to attenuate AKI by inducing IL-6 and HO-1 production, which results in lower inflammatory and apoptotic profiles in the kidney.  相似文献   
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