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Grooming among nonhuman primates is widespread and may represent an important service commodity that is exchanged within a biological marketplace. In this study, using focal animal sampling methods, we recorded grooming relationships among 12 adult females in a free-ranging group of Tibetan macaques (Macaca thibetana) at Huangshan, China, to determine the influence of rank and kinship on grooming relationships, and whether females act as reciprocal traders (exchange grooming received for grooming given) or interchange traders (interchange grooming for social tolerance or other commodities). The results showed that: (1) grooming given was positively correlated with grooming received; (2) kinship did not exert a significant influence on grooming reciprocity; and (3) grooming reciprocity occurred principally between individuals of adjacent rank; however, when females of different rank groomed, females tended to groom up the hierarchy (lower ranking individuals groomed higher ranking individuals more than vice versa). Our results support the contention that both grooming reciprocity and the interchange of grooming for tolerance represent important social tactics used by female Tibetan macaques. 相似文献
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Yunjiao Wang Gang He Feng Wang Chenke Zhang Zilu Ge Xiaolong Zheng Honghao Deng Chengsong Yuan Binghua Zhou Xu Tao Jiqiang Zhang Kanglai Tang 《Journal of cellular and molecular medicine》2019,23(11):7535-7544
Tendon injury repairs are big challenges in sports medicine, and fatty infiltration after tendon injury is very common and hampers tendon injury healing process. Tendon stem cells (TSCs), as precursors of tendon cells, have shown promising effect on injury tendon repair for their tenogenesis and tendon extracellular matrix formation. Adipocytes and lipids accumulation is a landmark event in pathological process of tendon injury, and this may induce tendon rupture in clinical practice. Based on this, it is important to inhibit TSCs adipogenesis and lipids infiltration to restore structure and function of injury tendon. Aspirin, as the representative of non‐steroidal anti‐inflammatory drugs (NSAIDs), has been widely used in tendon injury for its anti‐inflammatory and analgesic actions, but effect of aspirin on TSCs adipogenesis and fatty infiltration is still unclear. Under adipogenesis conditions, TSCs were treated with concentration gradient of aspirin. Oil red O staining was performed to observe changes of lipids accumulation. Next, we used RNA sequencing to compare profile changes of gene expression between induction group and aspirin‐treated group. Then, we verified the effect of filtrated signalling on TSCs adipogenesis. At last, we established rat tendon injury model and compared changes of biomechanical properties after aspirin treatment. The results showed that aspirin decreased lipids accumulation in injury tendon and inhibited TSCs adipogenesis. RNA sequencing filtrated PTEN/PI3K/AKT signalling as our target. After adding the signalling activators of VO‐Ohpic and IGF‐1, inhibited adipogenesis of TSCs was reversed. Still, aspirin promoted maximum loading, ultimate stress and breaking elongation of injury tendon. In conclusion, by down‐regulating PTEN/PI3K/AKT signalling, aspirin inhibited adipogenesis of TSCs and fatty infiltration in injury tendon, promoted biomechanical properties and decreased rupture risk of injury tendon. All these provided new therapeutic potential and medicine evidence of aspirin in treating tendon injury and tendinopathy. 相似文献
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肿瘤坏死因子相关的凋亡诱导配体(TRAIL)cDNA的克隆与表达 总被引:5,自引:0,他引:5
肿瘤坏死因子相关凋亡诱导配体(tumornecrosisfactorrelatedapoptosisinducingligand,TRAIL)是新近发现的肿瘤坏死因子家族成员,亦称凋亡素2配体(Apo2ligand,Apo2L)[1,2].由于TNF参与机体的免疫调节和炎症反应,并发挥细胞毒作用,因而为世人所瞩目[3,4].研究表明,TRAIL与TNF和Fas/Apo1配体一样,为典型的Ⅱ型跨膜蛋白,C端细胞外区域形成同源三聚体的亚结构,而N端15~40氨基酸为疏水区域并形成跨膜结… 相似文献
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Huabin Zhao Binghua Ru Emma C. Teeling Christopher G. Faulkes Shuyi Zhang Stephen J. Rossiter 《PloS one》2009,4(12)
The ecological radiation of mammals to inhabit a variety of light environments is largely attributed to adaptive changes in their visual systems. Visual capabilities are conferred by anatomical features of the eyes as well as the combination and properties of their constituent light sensitive pigments. To test whether evolutionary switches to different niches characterized by dim-light conditions coincided with molecular adaptation of the rod pigment rhodopsin, we sequenced the rhodopsin gene in twenty-two mammals including several bats and subterranean mole-rats. We compared these to thirty-seven published mammal rhodopsin sequences, from species with divergent visual ecologies, including nocturnal, diurnal and aquatic groups. All taxa possessed an intact functional rhodopsin; however, phylogenetic tree reconstruction recovered a gene tree in which rodents were not monophyletic, and also in which echolocating bats formed a monophyletic group. These conflicts with the species tree appear to stem from accelerated evolution in these groups, both of which inhabit low light environments. Selection tests confirmed divergent selection pressures in the clades of subterranean rodents and bats, as well as in marine mammals that live in turbid conditions. We also found evidence of divergent selection pressures among groups of bats with different sensory modalities based on vision and echolocation. Sliding window analyses suggest most changes occur in transmembrane domains, particularly obvious within the pinnipeds; however, we found no obvious pattern between photopic niche and predicted spectral sensitivity based on known critical amino acids. This study indicates that the independent evolution of rhodopsin vision in ecologically specialised groups of mammals has involved molecular evolution at the sequence level, though such changes might not mediate spectral sensitivity directly. 相似文献
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Expression of P2X receptors on immune cells in the rat liver during postnatal development 总被引:1,自引:0,他引:1
Xiang Z Lv J Jiang P Chen C Jiang B Burnstock G 《Histochemistry and cell biology》2006,126(4):453-463
Single and double-labeling immunofluorescence and RT-PCR expression of P2X receptor proteins and mRNAs were used in a study of the liver of postnatal rats. OX62 and ED1 were used as markers for dendritic and macrophage (Kupffer) cells respectively. The results showed that the P2X6 receptor subunit was up-regulated by 15-fold on hepatic sinusoid cells during postnatal days P1 to P60. Subpopulations of Kupffer cells co-expressed P2X4 and P2X6 receptor subunits and dendritic cells co-expressed P2X4 and P2X7 receptor subunits. Lipopolysaccharide (endotoxin) injected into the peritoneal cavity led to increased expression of the P2X6 receptor on Kupffer cells, suggesting that the P2X6 receptor subunit may be up-regulated by endotoxin. This study presents the first evidence that P2X receptors are widely distributed in the rat liver immune system and that activation of Kupffer and dendritic cells in the rat liver might be regulated by extracellular ATP. 相似文献
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Lithospermic acid (LSA) was originally isolated from the roots of Salvia mitiorrhiza, a common herb of oriental medicine. Previous studies demonstrated that LSA has antioxidant effects. In this study, we investigated the in vitro xanthine oxidase (XO) inhibitory activity, and in vivo hypouricemic and anti-inflammatory effects of rats. XO activity was detected by measuring the formation of uric acid or superoxide radicals in the xanthine/xanthine oxidase system. The results showed that LSA inhibited the formation of uric acid and superoxide radicals significantly with an IC50 5.2 and 1.08 microg/ml, respectively, and exhibited competitive inhibition. It was also found that LSA scavenged superoxide radicals directly in the system beta-NADH/PMS and inhibited the production of superoxide in human neutrophils stimulated by PMA and fMLP. LSA was also found to have hypouricemic activity on oxonate-pretreated rats in vivo and have anti-inflammatory effects in a model of gouty arthritis. These results suggested that LSA is a competitive inhibitor of XO, able to directly scavenge superoxide and inhibit superoxide production in vitro, and presents hypouricemic and anti-inflammatory actions in vivo. 相似文献