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991.
Four new alkaloids, daphnioldhanins D-G (1-4, resp.), together with five known alkaloids, daphmacropodine (5), secodaphniphylline (6), deoxycalyciphylline B (7), deoxyisocalyciphylline B (8), and daphmanidin A (9), were isolated from the roots of Daphniphyllum oldhami. Their structures were elucidated on the basis of spectroscopic data and chemical methods. Compound 1 at 2.0 microM showed potent antioxidant activity against H(2)O(2)-induced impairment in PC12 cells. 相似文献
992.
Meythaler M Wang Z Martinot A Pryputniewicz S Kasheta M McClure HM O'Neil SP Kaur A 《Journal of immunology (Baltimore, Md. : 1950)》2011,186(9):5151-5161
Although the cellular immune response is essential for controlling SIV replication in Asian macaques, its role in maintaining nonpathogenic SIV infection in natural hosts such as sooty mangabeys (SM) remains to be defined. We have previously shown that similar to rhesus macaques (RM), SM are able to mount a T lymphocyte response against SIV infection. To investigate early control of SIV replication in natural hosts, we performed a detailed characterization of SIV-specific cellular immunity and viral control in the first 6 mo following SIV infection in SM. Detection of the initial SIV-specific IFN-γ ELISPOT response in SIVsmE041-infected SM coincided temporally with a decline in peak plasma viremia and was similar in magnitude, specificity, and breadth to SIVsmE041-infected and SIVmac239-infected RM. Despite these similarities, SM showed a greater reduction in postpeak plasma viremia and a more rapid disappearance of productively SIV-infected cells from the lymph node compared with SIVmac239-infected RM. The early Gag-specific CD8(+) T lymphocyte response was significantly more polyfunctional in SM compared with RM, and granzyme B-positive CD8(+) T lymphocytes were present at significantly higher frequencies in SM even prior to SIV infection. These findings suggest that the early SIV-specific T cell response may be an important determinant of lymphoid tissue viral clearance and absence of lymph node immunopathology in natural hosts of SIV infection. 相似文献
993.
Chen Zhi-xian Li Shu-jun Yue Jian-xiong Jiao Gai-li Liu Shao-xiang She Jian-ming Wu Jing-yin Wang Hai-bo 《植物学报(英文版)》1989,31(12)
Protoplasts were isolated from an embryogenic suspension culture of commercial cotton cv. The protoplasts were released enzymatically and isolated by centrifugation on a sucrose cushion. The isolated protoplasts were initially cultured in a liquid medium with K3 mineral salts and modified Km8p organic compositions, supplemented with 0.05–0.1 mg/l 2,4-D, 0.2–0.5 mg/l 2ip in the dark. The regenerated plantlets from protoplasts of coker312 and coker 201 cv. were obtained. Embryogenesis from protoplast of Jin4 cv. and microcolonies form protoplasts of JiHe321 and Lul cv. were observed. 相似文献
994.
Hualin Ma Yaojiong Wu Wanfan Zhang Yong Dai Furong Li Ying Xu Yunshuai Wang Huiying Tu Wuxian Li Xinzhou Zhang 《Cytotherapy》2013,15(6):703-711
Background aimsThe potential protective effects of mesenchymal stromal cells (MSCs) on some kidney diseases has been reported. However, the effect of MSCs on doxorubicin-induced nephropathy is still poorly understood.MethodsRats with doxorubicin-induced kidney injuries were treated with human cord-derived MSCs. Human MSCs were first labeled with 5-bromo-2′-deoxyuridine to track their homing in kidneys after infusion.ResultsAlleviation of proteinuria, decreased serum albumin, alleviation of lipid disorders and histologic alterations were found in rats 4 weeks after treatment with MSCs, particularly in rats that were given repeat doses. Decreases in serum levels of interleukin-6, tumor necrosis factor-α and prostaglandin E2 and decreases in messenger RNA levels of kidney tissue cylooxygenase-2 and EP4 were found in MSC-treated rats. MSC-treated rats also displayed an increase in serum interleukin-10 levels.ConclusionsThese results indicate that MSCs ameliorate doxorubicin-induced kidney injuries and inflammation, suggesting a potential clinical treatment for inflammatory kidney diseases. 相似文献
995.
T Kubota J Wang T W G?bel R D Hockett M D Cooper C H Chen 《Journal of immunology (Baltimore, Md. : 1950)》1999,163(7):3858-3866
Mammalian TCR delta genes are located in the midst of the TCR alpha gene locus. In the chicken, one large V delta gene family, two D delta gene segments, two J delta gene segments, and one C delta gene have been identified. The TCR delta genes were deleted on both alleles in alpha beta T cell lines, thereby indicating conservation of the combined TCR alpha delta locus in birds. V alpha and V delta gene segments were found to rearrange with one, both or neither of the D delta segments and either of the two J delta segments. Exonuclease activity, P-addition, and N-addition during VDJ delta rearrangement contributed to TCR delta repertoire diversification in the first embryonic wave of T cells. An unbiased V delta 1 repertoire was observed at all ages, but an acquired J delta 1 usage bias occurred in the TCR delta repertoire. The unrestricted combinatorial diversity of relatively complex TCR gamma and delta loci may contribute to the remarkable abundance of gamma delta T cells in this avian representative. 相似文献
996.
Background
A number of databases have been developed to collect disease-related molecular, phenotypic and environmental features (DR-MPEs), such as genes, non-coding RNAs, genetic variations, drugs, phenotypes and environmental factors. However, each of current databases focused on only one or two DR-MPEs. There is an urgent demand to develop an integrated database, which can establish semantic associations among disease-related databases and link them to provide a global view of human disease at the biological level. This database, once developed, will facilitate researchers to query various DR-MPEs through disease, and investigate disease mechanisms from different types of data.Methodology
To establish an integrated disease-associated database, disease vocabularies used in different databases are mapped to Disease Ontology (DO) through semantic match. 4,284 and 4,186 disease terms from Medical Subject Headings (MeSH) and Online Mendelian Inheritance in Man (OMIM) respectively are mapped to DO. Then, the relationships between DR-MPEs and diseases are extracted and merged from different source databases for reducing the data redundancy.Conclusions
A semantically integrated disease-associated database (SIDD) is developed, which integrates 18 disease-associated databases, for researchers to browse multiple types of DR-MPEs in a view. A web interface allows easy navigation for querying information through browsing a disease ontology tree or searching a disease term. Furthermore, a network visualization tool using Cytoscape Web plugin has been implemented in SIDD. It enhances the SIDD usage when viewing the relationships between diseases and DR-MPEs. The current version of SIDD (Jul 2013) documents 4,465,131 entries relating to 139,365 DR-MPEs, and to 3,824 human diseases. The database can be freely accessed from: http://mlg.hit.edu.cn/SIDD. 相似文献997.
Miao Liu Yanfei Ru Yihua Gu Jianan Tang Tiancheng Zhang Jun Wu Fudong Yu Yao Yuan Chen Xu Jian Wang Huijuan Shi 《Biochimica et Biophysica Acta (BBA)/General Subjects》2018,1862(3):660-668
Background
We previously cloned the Ssp411 gene. We found that the Ssp411 protein is predominantly expressed in elongated spermatids in the rat testis in a stage-dependent manner. Although our findings strongly suggested that Ssp411 might play an important role in mammalian spermatogenesis, this hypothesis has not been studied.Methods
We first used real-time PCR, Western blotting and immunohistochemistry to confirm that the expression pattern of Ssp411 in several murine tissues is similar to its expression pattern in corresponding rat tissues. To better understand the roles of Ssp411 in male reproduction in vivo, we identified and characterized an Ssp411 expression-disrupted murine strain (Ssp411PB/PB) that was generated by piggyBac (PB) transposon insertion. We studied Ssp411-interacting proteins using proteome microarray, co-IP and GST pull-down assay.Results
Both Ssp411 mRNA and protein were detected exclusively in spermatids after step 9 during spermiogenesis in testis. Phenotypic analysis suggested that only Ssp411PB/PB males are sterile. These males have smaller testes, reduced sperm counts, decreased sperm motility and deformed spermatozoa. Microscopy analysis indicated that the manchette, a structurally reshaped sperm head, is aberrant in Ssp411PB/PB spermatids. The results of proteome microarray analysis and GST pull-down assays suggested that Ssp411 participates the ubiquitin-proteasome system by interacting with PSMC3. This has been reported to be manchette-associated and important for the head shaping of spermatids.Conclusions
Our study suggested that Ssp411 is required for spermiogenesis. It seems to play a role in sperm head shaping. The lack of Ssp411 causes sperm deformation and results in male infertility.General significance
Ssp411PB/PB mouse strain is an animal model of idiopathic oligoasthenoteratozoospermia (iOAT), and the gene may represent a therapeutic target for iOAT patients. 相似文献998.
Synergistic interactions between Glomus mosseae and Bradyrhizobium japonicum in enhancing proton release from nodules and hyphae 总被引:1,自引:0,他引:1
Soybean (Glycine max L. Merr.) seedlings were inoculated with Glomus mosseae (GM) and Bradyrhizobium japonicum (BJ) together or separately to study the effect of interactions on net H+ effluxes of nodules or extraradical hyphae by in vivo vibrating electrode techniques. GM promoted three-fold the H+ effluxes of nodules on mycorrhizal lateral roots and BJ increased eight-fold the net H+ effluxes of hyphae developing in the vicinity of nodules on lateral roots. Increments in plant P content were positively
and linearly correlated with the net H+ efflux of nodules and hyphae. It is concluded that increased H+ effluxes of nodules resulted from enhanced nitrogenase activities induced by the presence of the AM fungus in lateral roots.
The results point to additive effects of interactions between mycorrhizal fungi and rhizobia in increasing the extent of acidification
of the “nodulesphere” and the hyposphere. 相似文献
999.
Mingjun Wang Jian Wu Erye Zhou Xin Chang Jianhe Gan Tao Cheng 《Journal of cellular physiology》2019,234(11):20139-20148
1000.
Florian Wilfling Huajin Wang Joel T. Haas Natalie Krahmer Travis J. Gould Aki Uchida Ji-Xin Cheng Morven Graham Romain Christiano Florian Fröhlich Xinran Liu Kimberly K. Buhman Rosalind A. Coleman Joerg Bewersdorf Robert V. Farese Tobias C. Walther 《Developmental cell》2013,24(4):384-399
Highlights? Triacylglyceride (TG) synthesis is coupled with lipid droplet (LD) growth ? Two LD populations exist: growing LDs, containing TG enzymes, and small LDs ? Specific TG synthesis enzymes move from the ER to LDs through membrane bridges ? LD localization of TG enzymes mediates expansion of a subset of LDs 相似文献