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排序方式: 共有407条查询结果,搜索用时 46 毫秒
71.
72.
Madhuri S. Salker Jaya Nautiyal Jennifer H. Steel Zoe Webster Sandra ?u?urovi? Marilena Nicou Yogesh Singh Emma S. Lucas Keisuke Murakami Yi-Wah Chan Sean James Yazan Abdallah Mark Christian B. Anne Croy Biserka Mulac-Jericevic Siobhan Quenby Jan J. Brosens 《PloS one》2012,7(12)
Decidualization renders the endometrium transiently receptive to an implanting blastocyst although the underlying mechanisms remain incompletely understood. Here we show that human endometrial stromal cells (HESCs) rapidly release IL-33, a key regulator of innate immune responses, upon decidualization. In parallel, differentiating HESCs upregulate the IL-33 transmembrane receptor ST2L and other pro-inflammatory mediators before mounting a profound anti-inflammatory response that includes downregulation of ST2L and increased expression of the soluble decoy receptor sST2. We demonstrate that HESCs secrete factors permissive of embryo implantation in mice only during the pro-inflammatory phase of the decidual process. IL-33 knockdown in undifferentiated HESCs was sufficient to abrogate this pro-inflammatory decidual response. Further, sequential activation of the IL-33/ST2L/sST2 axis was disordered in decidualizing HESCs from women with recurrent pregnancy loss. Signals from these cultures prolonged the implantation window but also caused subsequent pregnancy failure in mice. Thus, Il-33/ST2 activation in HESCS drives an autoinflammatory response that controls the temporal expression of receptivity genes. Failure to constrain this response predisposes to miscarriage by allowing out-of-phase implantation in an unsupportive uterine environment. 相似文献
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74.
Optoacoustic (photoacoustic) imaging assumes that the detected signal varies linearly with laser energy. However, nonlinear intensity responses as a function of light fluence have been suggested in optoacoustic microscopy, that is, within the first millimeter of tissue. In this study, we explore the presence of nonlinearity deeper in tissue (~4 mm), as it relates to optoacoustic mesoscopy, and investigate the fluence required to delineate a switch from linear to nonlinear behavior. Optoacoustic signal nonlinearity is studied for different materials, different wavelengths and as a function of changes in the scattering and absorption coefficient of the medium imaged. We observe fluence thresholds in the mJ/cm2 range and preliminary find that different materials may exhibit different nonlinearity patterns. We discuss the implications of nonlinearity in relation to image accuracy and quantification in optoacoustic tomography. 相似文献
75.
Vera Malysheva Viacheslav Spirin Otto Miettinen Viviana Motato-Vásquez Hernawati Jaya Seelan Sathiya Seelan Karl-Henrik Larsson 《Mycological Progress》2018,17(7):805-814
Three species currently addressed to Protohydnum (Auriculariales) are studied with morphological and DNA methods. The genus Protohydnum is retained for the type species only, P. cartilagineum, recently re-collected in Brazil. The European species, P. piceicola, is not congeneric with P. cartilagineum and, therefore, placed in its own genus, Hyalodon, gen. nov. Another Hyalodon species, H. antui, is described from East Asia. The third member of Protohydnum sensu lato, P. sclerodontium from South-East Asia, is transferred to Elmerina. 相似文献
76.
Dawon Bae Jaya Gautam Hyeonjin Jang Suhrid Banskota Sang Yeul Lee Min-Ji Jeong A-Sol Kim Hong Chul Kim Iyn-Hyang Lee Tae-gyu Nam Jung-Ae Kim Byeong-Seon Jeong 《Bioorganic & medicinal chemistry letters》2018,28(2):107-112
Dysfunction or progressive degeneration of retinal pigment epithelium (RPE) contributes in the initial pathogenesis of age-related macular degeneration (AMD) causing irreversible vision loss, which makes RPE the prime target of the disease. The present study aimed to identify compounds to protect 4-hydroxynonenal (4-HNE)-induced RPE cell death by inhibiting NADPH oxidase 4 (NOX4) activity, not just as free radical scavengers, using ARPE-19, a human adult retinal pigment epithelial cell line, as a RPE representative. Novel thirty-two 6-ureido/thioureido-2,4,5-trimethylpyridin-3-ol derivatives 17 were synthesized and tested. We found that there was a strong correlation between level of protective effect of compounds 17 against 4-HNE-induced APRE-19 cell death and that of inhibitory activity against 4-HNE-induced superoxide production, and that most of the compounds 17 showed minimal DPPH radical scavenging activity. Compound 17–28 showed the best protective activity against 4-HNE-induced superoxide production (79.5% inhibition) and cell death (85.1% recovery) at 10?μM concentration, which was better than that of VAS2870, a NOX2/4 inhibitor. In addition, compound 17–28 blocked 4-HNE-induced apoptosis of ARPE-19 cells in a concentration-dependent manner. The results indicate that compound 17–28 may be a lead compound to develop AMD therapeutics. 相似文献
77.
Jaya Prabhakaran Mark Underwood Francesca Zanderigo Norman R. Simpson Anna R. Cooper Jeffrey Matthew Harry Rubin-Falcone Ramin V. Parsey J. John Mann J.S. Dileep Kumar 《Bioorganic & medicinal chemistry letters》2018,28(14):2432-2435
Radiosynthesis and in vivo evaluation of [11C]4-[5-(4-methylphenyl)-3-(trifluoromethyl)-1H-pyrazol-1-yl]benzenesulfonamide (methoxy analogue of valdecoxib, [11C]MOV), a COX-2 inhibitor, was conducted in rat and baboon. Synthesis of the reference standard MOV (3), and its desmethyl precursor 2 for radiolabeling were performed using 1,2-diphenylethan-1-one as the starting material in five steps with 15% overall yield. Radiosynthesis of [11C]MOV was accomplished in 40?±?10% yield and?>99% radiochemical purity by reacting the precursor 2 in dimethyl formamide (DMF) with [11C]CH3I followed by removal of the dimethoxytrityl (DMT) protective group using trifluroacetic acid. PET studies in anesthetized baboon showed very low uptake and homogeneous distribution of [11C]MOV in brain. The radioligand underwent rapid metabolism in baboon plasma. MicroPET studies in male Sprague Dawley rats revealed [11C]MOV binding in lower thorax. The tracer binding in rats was partially blocked in heart and duodenum by the administration of 1?mg/kg oral dose of COX-2 inhibitor valdecoxib. 相似文献
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79.
C. Luke Williams Tyler L. Westover Rachel M. Emerson Jaya Shankar Tumuluru Chenlin Li 《Bioenergy Research》2016,9(1):1-14
Terrestrial lignocellulosic biomass has the potential to be a carbon neutral and domestic source of fuels and chemicals. However, the innate variability of biomass resources, such as herbaceous and woody materials, and the inconsistency within a single resource due to disparate growth and harvesting conditions, presents challenges for downstream processes which often require materials that are physically and chemically consistent. Intrinsic biomass characteristics, including moisture content, carbohydrate and ash compositions, bulk density, and particle size/shape distributions are highly variable and can impact the economics of transforming biomass into value-added products. For instance, ash content increases by an order of magnitude between woody and herbaceous feedstocks (from ~0.5 to 5 %, respectively) while lignin content drops by a factor of two (from ~30 to 15 %, respectively). This increase in ash and reduction in lignin leads to biofuel conversion consequences, such as reduced pyrolysis oil yields for herbaceous products as compared to woody material. In this review, the sources of variability for key biomass characteristics are presented for multiple types of biomass. Additionally, this review investigates the major impacts of the variability in biomass composition on four conversion processes: fermentation, hydrothermal liquefaction, pyrolysis, and direct combustion. Finally, future research processes aimed at reducing the detrimental impacts of biomass variability on conversion to fuels and chemicals are proposed.© 2015 Battelle Energy Alliance, LLC, contract manager for Idaho National Laboratory. 相似文献
80.
G. Havazhagan S. S. Riar A. K. Kain Jaya Bardhan Pauline Thomas 《International journal of biometeorology》1989,33(3):165-172
Two groups of male rats were exposed to simulated altitudes of 6060 m and 7576 m for 6 h/day for 7 days (intermittent exposure). In two additional groups of animals exposed to the same altitude, 100 mg of ascorbic acid (AA) was fed daily for 5 days prior to the exposure period and also during the exposure period. Rats that did not receive AA showed loss of body weight and weight of reproductive organs after exposure. Sex organs showed atrophy on histological examination and there was a deterioration in spermatozoal quality. There was an increase in alkaline and acid phosphatase, and decrease in protein, sialic acid and glyceryl phosphorylcholine content in various reproductive tissues after exposure. All the above changes in histology and biochemical composition could be partially prevented by AA supplementation. AA supplementation can therefore protect the male reproductive system from deleterious effects of hypoxia. The probable mechanism of action of AA is discussed. 相似文献