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SAR studies on amides, ureas, and vinylogous amides derived from pyrrolidine led to the discovery of several potent hNK(1) antagonists. One particular vinylogous amide (45b) had excellent potency, selectivity, pharmacokinetic profile, and functional activity in vivo. An in vivo rhesus macaque brain receptor occupancy PET study for compound 45b revealed an estimated Occ(90) approximately 300 ng/ml.  相似文献   
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In the infarcted rat heart, the increase of NO occurs in the hypertrophied myocardium of non-infarcted areas and its antihypertrophic efficacy has been well established. As another endogenous regulator and the reliable index of heart pathology, B-type natriuretic peptide also exhibits the antihypertrophic properties in many tissues by elevating intracellular cGMP. Several studies indicate that natriuretic peptides family may exert some actions in part via a nitric oxide pathway following receptor-mediated stimulation of iNOS. Therefore, it raises our great interest to ask what role NO plays in the antihypertrophic actions of B-type natriuretic peptide in cardiomyocytes. Incubation of cardiomyocytes under mild hypoxia for 12 h caused a significant increase in cellular protein content, protein synthesis and cell surface sizes. This growth stimulation was suppressed by exogenous B-type natriuretic peptide in a concentration dependent manner. Furthermore, the generation of intracellular cGMP, the upregulation of iNOS mRNA expression, the increase of iNOS activity and subsequent nitrite generation in hypertrophic cardiomyocytes was also increased by B-type natriuretic peptide. AG, a selective iNOS inhibitor, inhibited the upregulation of iNOS expression and the increase of iNOS activity by the combination of B-type natriuretic peptide/mild hypoxia or by the combination of 8-bromo-cGMP/mild hypoxia. Rp-8-br-cGMP, cGMP dependent protein kinase inhibitor, attenuated the actions of B-type natriuretic peptide and 8-bromo-cGMP which increases intracellular cGMP independent of B-type natriuretic peptide. In conclusion, our present data suggest that B-type natriuretic peptide exerted the antihypertrophic effects in cardiomyocytes, which was partially attributed to induction of iNOS-derived NO by cGMP pathway.  相似文献   
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Sandwich‐type hybrid carbon nanosheets (SCNMM) consisting of graphene and micro/mesoporous carbon layer are fabricated via a double template method using graphene oxide as the shape‐directing agent and SiO2 nanoparticles as the mesoporous guide. The polypyrrole synthesized in situ on the graphene oxide sheets is used as a carbon precursor. The micro/mesoporous strcutures of the SCNMM are created by a carbonization process followed by HF solution etching and KOH treatment. Sulfur is impregnated into the hybrid carbon nanosheets to generate S@SCNMM composites for the cathode materials in Li‐S secondary batteries. The microstructures and electrochemical performance of the as‐prepared samples are investigated in detail. The hybrid carbon nanosheets, which have a thickness of about 10–25 nm, high surface area of 1588 m2 g?1, and broad pore size distribution of 0.8–6.0 nm, are highly interconnected to form a 3D hierarchical structure. The S@SCNMM sample with the sulfur content of 74 wt% exhibits excellent electrochemical performance, including large reversible capacity, good cycling stability and coulombic efficiency, and good rate capability, which is believed to be due to the structure of hybrid carbon materials with hierarchical porous structure, which have large specific surface area and pore volume.  相似文献   
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从江浙蝮蛇中分离纯化的碱性磷脂酶A2在pH9.5,0.05mmol/LCHES缓冲液中,用汽相悬滴扩散的方法,获得了适用于高分辨率X射线结构分析的单晶.经X200B面探测器分析,表明该晶体属于正交晶系,P2I2I2I空间群,晶胞参数为a=97.13,b=103.69,c=23.27.并收集了一套衍射数据,独立衍射点数12001个,数据完整度为86.2%,Rmerge为0.0459.最高分辨率达2.0,根据分子量与晶胞体积估算,一个不对称单位含两个分子.  相似文献   
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iQPR技术处理污水是一项新型尖端的技术,此技术可以成功降低污水乃至受到污染的地下水中的各种污染指标。但是,iQPR技术处理污水尤其是地下水是否存在潜在的生物安全性问题有待于进一步研究。因此,为评估iQPR技术对生物安全性的影响,本研究首先分析了三种不同iQPR法处理水的水质成分;其次系统研究了iQPR水对SD鼠在个体水平、组织水平和病理形态学损伤的研究。研究表明:iQPR处理的水质成分较对照组普通饮用水好,在个体组织水平检测未见异常,尽管其中一组iQPR处理水造成了SD鼠的脾小体增大,但是可能的原因是水处理环节存在微生物污染现象,因此,初步认定此技术未造成SD大鼠的个体损伤。本研究为揭示iQPR处理的水对生物体的安全性评价提供一个理论依据。  相似文献   
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Necroptosis is a unique programmed death mechanism of necrotic cells. However, its role and specific mechanism in cancer remain unclear, and a systematic pan‐cancer analysis of necroptosis is yet to be conducted. Thus, we performed a specific pan‐cancer analysis using The Cancer Genome Atlas and Genotype‐Tissue Expression databases to analyse necroptosis expression in terms of cancer prognosis, DNA methylation status, tumour mutative burden, microsatellite instability, immune cell infiltration in different types of cancer and molecular mechanisms. For the first time, we explored the correlation between necroptosis and immunotherapy prognosis. Thus, our study provides a relatively comprehensive understanding of the carcinogenicity of necroptosis in different types of cancer. It is suggested that necroptosis can be used to evaluate the sensitivity of different patients to immunotherapy and may become a potential target for tumour immunotherapy.  相似文献   
60.
Studies on some plant species have shown that increasing the growth temperature gradually or pretreating with high temperature can lead to obvious photosynthetic acclimation to high temperature. To test whether this acclimation arises from heat adaptation of ribulose 1,5‐bisphosphate carboxylase/oxygenase (Rubisco, EC 4.1.1.39) activation mediated by Rubisco activase (RCA), gene expression of RCA large isoform (RCAL) and RCA small isoform (RCAS) in rice was determined using a 4‐day heat stress treatment [40/30°C (day/night)] followed by a 3‐day recovery under control conditions [30/22°C (day/night)]. The heat stress significantly induced the expression of RCAL as determined by both mRNA and protein levels. Correlative analysis indicated that RCAS protein content was extremely significantly related to Rubisco initial activity and net photosynthetic rate (Pn) under both heat stress and normal conditions. Immunoblot analysis of the Rubisco–RCA complex revealed that the ratio of RCAL to Rubisco increased markedly in heat‐acclimated rice leaves. Furthermore, transgenic rice plants expressing enhanced amounts of RCAL exhibited higher thermotolerance in Pn and Rubisco initial activity and grew better at high temperature than wild‐type (WT) plants and transgenic rice plants expressing enhanced amounts of RCAS. Under normal conditions, the transgenic rice plants expressing enhanced amounts of RCAS showed higher Pn and produced more biomass than transgenic rice plants expressing enhanced amounts of RCAL and wild‐type plants. Together, these suggest that the heat‐induced RCAL may play an important role in photosynthetic acclimation to moderate heat stress in vivo, while RCAS plays a major role in maintaining Rubisco initial activity under normal conditions.  相似文献   
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