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71.
72.
Specialized pro‐resolving mediators actively limit inflammation and support tissue regeneration, but their role in age‐related muscle dysfunction has not been explored. We profiled the mediator lipidome of aging muscle via liquid chromatography‐tandem mass spectrometry and tested whether treatment with the pro‐resolving mediator resolvin D1 (RvD1) could rejuvenate the regenerative ability of aged muscle. Aged mice displayed chronic muscle inflammation and this was associated with a basal deficiency of pro‐resolving mediators 8‐oxo‐RvD1, resolvin E3, and maresin 1, as well as many anti‐inflammatory cytochrome P450‐derived lipid epoxides. Following muscle injury, young and aged mice produced similar amounts of most pro‐inflammatory eicosanoid metabolites of cyclooxygenase (e.g., prostaglandin E2) and 12‐lipoxygenase (e.g., 12‐hydroxy‐eicosatetraenoic acid), but aged mice produced fewer markers of pro‐resolving mediators including the lipoxins (15‐hydroxy‐eicosatetraenoic acid), D‐resolvins/protectins (17‐hydroxy‐docosahexaenoic acid), E‐resolvins (18‐hydroxy‐eicosapentaenoic acid), and maresins (14‐hydroxy‐docosahexaenoic acid). Similar absences of downstream pro‐resolving mediators including lipoxin A4, resolvin D6, protectin D1/DX, and maresin 1 in aged muscle were associated with greater inflammation, impaired myofiber regeneration, and delayed recovery of strength. Daily intraperitoneal injection of RvD1 had minimal impact on intramuscular leukocyte infiltration and myofiber regeneration but suppressed inflammatory cytokine expression, limited fibrosis, and improved recovery of muscle function. We conclude that aging results in deficient local biosynthesis of specialized pro‐resolving mediators in muscle and that immunoresolvents may be attractive novel therapeutics for the treatment of muscular injuries and associated pain in the elderly, due to positive effects on recovery of muscle function without the negative side effects on tissue regeneration of non‐steroidal anti‐inflammatory drugs.  相似文献   
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Involvement of the endocannabinoid system in periodontal healing   总被引:1,自引:0,他引:1  
Endocannabinoids including anandamide (AEA) and 2-arachidonoylglycerol (2-AG) are important lipid mediators for immunosuppressive effects and for appropriate homeostasis via their G-protein-coupled cannabinoid (CB) receptors in mammalian organs and tissues, and may be involved in wound healing in some organs. The physiological roles of endocannabinoids in periodontal healing remain unknown. We observed upregulation of the expression of CB1/CB2 receptors localized on fibroblasts and macrophage-like cells in granulation tissue during wound healing in a wound-healing model in rats, as well as an increase in AEA levels in gingival crevicular fluid after periodontal surgery in human patients with periodontitis. In-vitro, the proliferation of human gingival fibroblasts (HGFs) by AEA was significantly attenuated by AM251 and AM630, which are selective antagonists of CB1 and CB2, respectively. CP55940 (CB1/CB2 agonist) induced phosphorylation of the extracellular-regulated kinases (ERK) 1/2, p38 mitogen-activated protein kinase (p38MAPK), and Akt in HGFs. Wound closure by CP55940 in an in-vitro scratch assay was significantly suppressed by inhibitors of MAP kinase kinase (MEK), p38MAPK, and phosphoinositol 3-kinase (PI3-K). These findings suggest that endocannabinoid system may have an important role in periodontal healing.  相似文献   
75.
Coraliomargarita akajimensis Yoon et al. 2007 is the type species of the genus Coraliomargarita. C. akajimensis is an obligately aerobic, Gram-negative, non-spore-forming, non-motile, spherical bacterium that was isolated from seawater surrounding the hard coral Galaxea fascicularis. C. akajimensis is of special interest because of its phylogenetic position in a genomically under-studied area of the bacterial diversity. Here we describe the features of this organism, together with the complete genome sequence, and annotation. This is the first complete genome sequence of a member of the family Puniceicoccaceae. The 3,750,771 bp long genome with its 3,137 protein-coding and 55 RNA genes is a part of the Genomic Encyclopedia of Bacteria and Archaea project.  相似文献   
76.
Résumé L'AcridienGesonula punctifrons St?l attaque la Jacinthe d'eau (Eichhornia crassipes) dans plusieurs parties de l'Inde et est adapté à un habitat aquatique ou semi-aquatique. Les œufs, pondus dans les pétioles des feuilles, éclosent en 3 à 4 semaines. Les larves se développent en 4 à 5 semaines et demi, avec 5 mues. Les adultes vivent au maximum 4 à 5 mois en s'alimentant seulement de Jacinthe d'eau. En essais de laboratoire cet Acridien se nourrit activement deCanna orientalis dont les tiges sont percées de trous pour la ponte par les femelles, mais aucun œuf n'est déposé. Quarante trois autres plantes d'intérêt économique ont été expérimentées: plusieurs d'entre elles ont été l'objet d'attaques légères à modérées. L'analyse de la littérature concernant les plantes-h?tes du genreGesonula et la distribution deG. punctifrons montrent que cette espèce s'est adaptée secondairement àE. crassipes. Bien que cet Acridien s'observe en grand nombre dans quelques régions, l'ensemble de ses dégats à la mauvaise herbe n'est pas suffisant pour assurer le contr?le de celle-ci.

This research has been financed in part by a grant made by the United States Department of Agriculture under P. L. 480.  相似文献   
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The mTOR (mammalian or mechanistic Target of Rapamycin) is linked with oral cancer. Therefore, it is of interest to study the molecular docking-based binding of paclitaxel (a FDA approved drug for oral cancer) and its analogues with mTOR. Hence, we report the binding features of 10-Deacetyltaxol, 7-Epi-10-deacetyltaxol, 7-Epi-Taxol and 6alpha-Hydroxypaclitaxel with mTOR for further consideration.  相似文献   
79.
The aim of this study was to evaluate the effect of putrescine on ovarian activity and the rate of embryonic development in Cynopterus sphinx during delayed development. The result showed the presence of a rate‐limiting enzyme, ornithine decarboxylase‐1, in both ovary and utero‐embryonic unit of C. sphinx suggests a synthesis of putrescine in these sites. The corpus luteum showed increased, whereas utero‐embryonic unit showed decreased production of putrescine during delayed development as compared with the normal development. The bat treated in vivo with putrescine during delayed development showed increase in progesterone and estradiol synthesis, correlated with increased expression of luteinizing hormone receptor, steroidogenic acute receptor protein, and 3β‐hydroxysteroid dehydrogenase through extracellular signal‐regulated kinase (ERK1/2)‐mediated pathway in the ovary; but showed increase in the weight and expression of progesterone receptor (PR), B‐cell lymphoma 2, proliferating cell nucleus antigen, and vascular endothelial growth factor proteins in utero‐embryonic unit. The in vitro treatment of putrescine showed stimulatory whereas treatment with an inhibitor of putrescine, 2‐difluoromethylornithine caused an inhibitory effect on ovarian progesterone synthesis and cell proliferation, and cell survival in the utero‐embryonic unit. In conclusion, the putrescine showed two separate roles during embryonic diapause, high concentration of putrescine in the ovary may support corpus luteum and basal synthesis of progesterone, whereas a low level of putrescine causes retarded embryonic development by inhibiting cell proliferation in the utero‐embryonic unit. The bat treated with putrescine either directly promotes cell proliferation, cell survival, and angiogenic activities or acts indirectly increasing PR on utero‐embryonic unit thereby activating development in delayed embryo in C. sphinx.  相似文献   
80.
Protease inhibitors are well known to have several applications in medicine and biotechnology. Several plant sources are known to return potential protease inhibitors. In this study plants belonging to different families of Leguminosae, Malvaceae, Rutaceae, Graminae and Moringaceae were screened for the protease inhibitor. Among them Moringa oleifera, belonging to the family Moringaceae, recorded high level of protease inhibitor activity after ammonium sulfate fractionation. M. oleifera, which grows throughout most of the tropics and having several industrial and medicinal uses, was selected as a source of protease inhibitor since so far no reports were made on isolation of the protease inhibitor. Among the different parts of M. oleifera tested, the crude extract isolated from the mature leaves and seeds showed the highest level of inhibition against trypsin. Among the various extraction media evaluated, the crude extract prepared in phosphate buffer showed maximum recovery of the protease inhibitor. The protease inhibitor recorded high inhibitory activity toward the serine proteases thrombin, elastase, chymotrypsin and the cysteine proteases cathepsin B and papain which have more importance in pharmaceutical industry. The protease inhibitor also showed complete inhibition of activities of the commercially available proteases of Bacillus licheniformis and Aspergillus oryzae. However, inhibitory activities toward subtilisin, esperase, pronase E and proteinase K were negligible. Further, it was found that the protease inhibitor could prevent proteolysis in a commercially valuable shrimp Penaeus monodon during storage indicating the scope for its application as a seafood preservative. This is the first report on isolation of a protease inhibitor from M. oleifera.  相似文献   
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