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951.
Considering the high rate of osteoclast-related diseases worldwide, research targeting osteoclast formation/function is crucial. In vitro, we demonstrated that chitooligosaccharide (CS) dramatically inhibited osteoclastogenesis as well as osteoclast function dose-dependently. CS suppressed osteoclast-specific genes expression during osteoclastogenesis. Furthermore, we found that CS attenuated receptor activator of nuclear factor kappa B ligand (RANKL)-mediated mitogen-activated protein kinase (MAPK) pathway involving p38, erk1/2, and jnk, leading to the reduced expression of c-fos and nuclear factor of activated T cells c1 (NFATc1) during osteoclast differentiation. In vivo, we found CS protected rats from periodontitis-induced alveolar bone loss by micro-computerized tomography and histological analysis. Overall, CS inhibited RANKL-induced osteoclastogenesis and ligature-induced rat periodontitis model, probably by suppressing the MAPK/c-fos/NFATc1 signaling pathway. Therefore, CS may be a safe and promising treatment for osteoclast-related diseases.  相似文献   
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An increasing number of studies show that platelet‐rich plasma (PRP) is effective for androgenic alopecia (AGA). However, the underlying cellular and molecular mechanisms along with its effect on hair follicle stem cells are poorly understood. In this study, we designed to induce platelets in PRP to release factors by calcium chloride (PC) or by sonication where platelet lysates (PS) or the supernatants of platelet lysate (PSS) were used to evaluate their effect on the hair follicle activation and regeneration. We found that PSS and PS exhibited a superior effect in activating telogen hair follicles than PC. In addition, PSS injection into the skin activated quiescent hair follicles and induced K15+ hair follicle stem cell proliferation in K14‐H2B‐GFP mice. Moreover, PSS promoted skin‐derived precursor (SKP) survival in vitro and enhanced hair follicle formation in vivo. In consistence, protein array analysis of different PRP preparations revealed that PSS contained higher levels of 16 growth factors (out of 41 factors analysed) than PC, many of them have been known to promote hair follicle regeneration. Thus, our data indicate that sonicated PRP promotes hair follicle stem cell activation and de novo hair follicle regeneration.  相似文献   
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A new indole derivative colletoindole A ( 1 ), along with two new indole derivatives ( 2 and 3 ) and one known compound acropyrone ( 4 ) were isolated from cultures of Colletotrichum tropicale SCSIO 41022 derived from a mangrove plant Kandelia candel. The structures of 1 – 4 were determined by analysis of NMR and MS data. The cytotoxicity of 1 , 2 and 4 , and the COX‐2 inhibitory activity of 1 and 2 were evaluated.  相似文献   
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Two new cadinane-type sesquiterpenes, hypocreaterpenes A (1) and B (2), along with five known compounds (37) were isolated from a marine-derived fungus Hypocreales sp. strain HLS-104 isolated from a sponge Gelliodes carnosa. Their structures were determined by a combination of spectroscopic methods. All compounds were tested for the inhibitory effects on the nitric oxide (NO) production in lipopolysaccharide (LPS)-treated RAW264.7 cells. Among them, compounds 3 and 6 showed moderate anti-inflammatory activity with average maximum inhibition (Emax) values of 10.22% and 26.46% at 1 μM, respectively.  相似文献   
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