共查询到20条相似文献,搜索用时 15 毫秒
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P.M.Z. Coelho N.H. Toppa J.S. Feldmann R. Gonçalves R.T. Mello 《International journal for parasitology》1996,26(12):1393-1395
Persistence of down regulation of granoloma size was studied in mice chronically infected with Schistosoma mansoni and cured by chemotherapy. The animals were reinfected at 20-, 50-, 110- and 140-day intervals after treatment, and sacrificed 60 days post-reinfection. Reinfected animals were able to modulate the granulomatous inflammatory response, thus preventing a new acute phase. These findings may contribute to the explanation for the decrease of morbidity from human schistosomiasis seen in endemic areas following mass treatment. 相似文献
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Cellular senescence is a state of stable proliferation arrest of cells. The senescence pathway has many beneficial effects and is seen to be activated in damaged/stressed cells, as well as during embryonic development and wound healing. However, the persistence and accumulation of senescent cells in various tissues can also impair function and have been implicated in the pathogenesis of many age‐related diseases. Osteoarthritis (OA), a severely debilitating chronic condition characterized by progressive tissue remodeling and loss of joint function, is the most prevalent disease of the synovial joints, and increasing age is the primary OA risk factor. The profile of inflammatory and catabolic mediators present during the pathogenesis of OA is strikingly similar to the secretory profile observed in ‘classical’ senescent cells. During OA, chondrocytes (the sole cell type present within articular cartilage) exhibit increased levels of various senescence markers, such as senescence‐associated beta‐galactosidase (SAβGal) activity, telomere attrition, and accumulation of p16ink4a. This suggests the hypothesis that senescence of cells within joint tissues may play a pathological role in the causation of OA. In this review, we discuss the mechanisms by which senescent cells may predispose synovial joints to the development and/or progression of OA, as well as touching upon various epigenetic alterations associated with both OA and senescence. 相似文献
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A Lopez 《Journal of invertebrate pathology》1979,34(3):224-230
The basis of tumoral pathology in spiders is shown through histologic pictures of three different morbid cases, each affecting a particular species. The first two are merely tumors in terms of new growth visualized by gross examination: parietal reaction granuloma of opisthosoma in Peucetia lucasi (Oxyopidae) and hypodermocuticular cyst by ventral tegumentary inclusion in Psechrus alticeps (Psechridae). More original, the third case is a genuine neoplasm in the female genital tract of Pachygnatha clercki (Tetragnathidae). Its heavy invading proliferation exhibits several malignancy criteria but excludes metastasis. 相似文献
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IL‐7 suppresses macrophage autophagy and promotes liver pathology in Schistosoma japonicum‐infected mice 下载免费PDF全文
Jifeng Zhu Weiwei Zhang Lina Zhang Lei Xu Xiaojun Chen Sha Zhou Zhipeng Xu Ming Xiao Hui Bai Feng Liu Chuan Su 《Journal of cellular and molecular medicine》2018,22(7):3353-3363
In schistosomiasis japonica and mansoni, parasite eggs trapped in host liver elicit severe liver granulomatous inflammation that subsequently leads to periportal fibrosis, portal hypertension, haemorrhage or even death. Macrophages are critical for granuloma formation and the development of liver fibrosis during schistosomiasis. However, whether the aberrant regulation of macrophage autophagy has an effect on the development of liver immunopathology in schistosomiasis remains to be elucidated. In this study, we showed that Schistosoma japonicum (S. japonicum) egg antigen (SEA)‐triggered macrophage autophagy limited the development of pathology in host liver. However, engagement of IL‐7 receptor (IL‐7R/CD127) on macrophages by S. japonicum infection‐induced IL‐7 significantly suppressed SEA‐triggered macrophage autophagy, which led to an enhanced liver pathology. In addition, anti‐IL‐7 neutralizing antibody or anti‐CD127 blocking antibody treatment increased macrophage autophagy and suppressed liver pathology. Finally, we demonstrated that IL‐7 protects macrophage against SEA‐induced autophagy through activation of AMP‐activated protein kinase (AMPK). Our study reveals a novel role for IL‐7 in macrophage autophagy and identifies AMPK as a novel downstream mediator of IL‐7‐IL‐7R signalling and suggests that manipulation of macrophage autophagy by targeting IL‐7‐IL‐7R signalling may have the potential to lead to improved treatment options for liver pathogenesis in schistosomiasis. 相似文献
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LacdiNAc- and LacNAc-containing glycans induce granulomas in an in vivo model for schistosome egg-induced hepatic granuloma formation 总被引:4,自引:0,他引:4
Schistosomes, major parasitic helminths, express numerous glycoconjugatesthat provoke humoral and cellular immune responses in the infectedhuman host. The main pathology in schistosomiasis is due tothe formation of granulomas around tissue-trapped eggs and theresulting organ damage. By using a mouse model of inductionof granulomas by hepatic implantation of antigen-coated beads,it has been determined that the glycan part of schistosomalsoluble egg antigens (SEA) initiates granulomogenesis. To identifywhich individual glycan elements in this complex SEA mixtureare granulomogenic, we have tested in the same mouse model conjugatesof various synthetic oligosaccharides characteristic for schistosomeeggs, including GalNAcß1-4GlcNAc (LacdiNAc, LDN),Galß1-4(Fuc1-3)GlcNAc (Lewisx), Fuc1-2Fuc1-3GlcNAc(DF-Gn), and Fuc1-3GalNAcß1-4(Fuc1-3)GlcNAc (F-LDN-F).Ribonuclease (RNase) A and B, and different fetuin glycoformswere included as controls. Only beads that carry glycoconjugateswith terminal LacdiNAc or Galß1-4GlcNAc (LacNAc, LN)elements gave rise to granulomas, with macrophage, lymphocyte,and eosinophil levels similar to the granulomatous lesions causedby schistosome eggs in a natural infection. Uncoated beads,and beads coated with fucosylated glycoconjugates or glycoconjugateslacking terminally exposed Gal or GalNAc, only attracted a monolayerof macrophages. These results indicate that the formation ofhepatic granulomas is triggered specifically by glycoconjugateswhich carry terminal LacNAc or LacdiNAc, both constituents ofthe schistosome egg. 相似文献
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T. H. Dietz D. H. Neufeld H. Silverman S. H. Wright 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》1998,168(2):87-95
The effect of ambient osmolality on the height of lateral ciliated cells from the gills of two freshwater bivalve species
(Dreissena polymorpha, Toxolasma texasensis) was directly observed microscopically. The addition of 1 mmol · l−1 KCl to an artificial pondwater (APW) superfusion medium resulted in an increase in cell height. When the superfusion solution
was made hyperosmotic (∼90 mmol · kg−1 H2O) by the addition of 45 mmol · l−1 NaCl to APW, the cell height decreased by about 20–30% and there was no evidence of a regulatory volume increase over 20–30 min.
In contrast, when 1 mmol · l−1 KCl was added to the hyperosmotic medium the cell height always partially (40–50%) recovered. When the gill tissue was returned
to APW following the hyperosmotic treatment the cells returned to the original cell height. Bivalve gills superfused with
the hyperosmotic NaCl and KCl solution in the presence of 1 mmol · l−1 ouabain experienced a similar 25% decrease in cell height. When the ouabain-treated tissues were returned to APW the cells
swelled, overshooting the original cell height. These results indicate these freshwater bivalves have a limited ability for
cellular volume regulation using inorganic ions, but depend on a suitable balance of Na+ and K+ in the environment to effect regulatory volume changes.
Accepted: 17 October 1997 相似文献
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肝脏纤维化(hepatic fibrosis)是多种慢性肝病的共同病理基础,是进一步向肝硬化发展的中心环节。肝脏内一些免疫细胞如枯否细胞(Kupffer cell,KC)、树突状细胞(dendritic cell,DC)、T淋巴细胞、NK细胞(nature killer cell,NK cell)、B细胞等在多种致病因素刺激下激活,释放多种细胞因子和趋化因子,引起一系列病理变化,共同参与肝纤维化的发生和发展过程。本文主要从肝脏内各类免疫细胞以及分泌的细胞因子方面,对肝纤维化形成机制的最新研究进展进行综述。 相似文献
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Parasitism changes the host environment and may influence resource allocation between reproductive effort and somatic maintenance. We characterized the impact of dose-dependent schistosome exposure and/or infection establishment on intermediate host survival and reproduction. Four matched groups of Biomphalaria glabrata snails were individually exposed to increasing doses of Schistosoma mansoni parasites, with a fifth control group remaining unexposed. Increased mortality was observed amongst both snails infected and also those snails exposed to the parasite but within which infection did not establish, although only exposed but uninfected snails showed a dose-dependent increase in mortality. Snails also facultatively altered their reproductive output in response to parasite exposure: egg mass production decreased with increasing parasite dose in patently infected snails, whilst, in contrast, exposed but uninfected snails demonstrated a positive association between egg mass production and parasite dose in the post-patent period. These results uniquely suggest an exposure-dose-dependent post-patent fecundity compensation occurring in relation to the risk of future parasite-associated mortality. 相似文献
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Smith-Thomas LC Moustafa M Dawson RA Wagner M Balafa C Haycock JW Krauss AH Woodward DF MacNeil S 《Pigment cell research / sponsored by the European Society for Pigment Cell Research and the International Pigment Cell Society》2001,14(4):298-309
The purpose of this study was to examine some of the factors that may be relevant to regulating pigmentation in the human eye, specifically whether choroidal and iridial melanocytes are sensitive to regulation by epithelial and stromal cells and alpha-melanocyte stimulating hormone (alpha-MSH). Human choroidal and iridial melanocytes were established in culture and co-cultured with epithelial cells and stromal cells derived both from skin and from eye in order to determine their influence on choroidal and iridial melanocyte dopa oxidase activity. In all cases, co-culture of melanocytes with either epithelial cells or fibroblasts led to an increase in dopa oxidase activity during 5 days of co-culture. The extent of the increase ranged from 60% (non-significant) to as much as 185% when both fibroblasts and keratinocytes were present. The optimal ratio of fibroblasts to melanocytes was 1:10 (for dermal fibroblasts) or 1:2 (for iridial fibroblasts) and 1:1 for all epithelial cells to melanocytes. Both choroidal (three out of three cultures) and iridial (two out of three cultures) melanocytes showed increases in dopa oxidase activity to alpha-MSH when cultured in Green's media but the same cells cultured in MCDB153 were unresponsive to alpha-MSH. These in vitro studies suggest that ocular melanocytes have the capacity to be influenced by adjacent epithelial and stromal cells with respect to pigmentation. 相似文献
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Fei Yu Tao Xu Man Wang Wenguang Chang Peifeng Li Jianxun Wang 《European journal of cell biology》2018,97(7):474-482
Mitochondrial dynamics with constant fusion and fission plays vital roles in regulating cellular biological processes. Mitofusin 2 (Mfn2) is dynamin-related protein whose activity promotes mitochondrial fusion and maintains the homeostasis of mitochondrial dynamics. Advanced studies have demonstrated that Mfn2 is a multifunctional protein with signaling roles beyond fusion. Mfn2 is actively involved in various biological processes under both physical and pathological conditions, including mitochondrial transport and the interaction between endoplasmic reticulum/sarcoplasmic reticulum and mitochondria, as well as cell metabolism, apoptosis and autophagy. This review summarises the structural and functional properties of Mfn2, with focus on recent advances in its regulatory role in cardiovascular system. 相似文献