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781.
782.
目的:观察不同浓度透明质酸对白细胞介素1β与软骨滑膜联合培养模型中软骨基质代谢的影响与抑制炎性反应的作用,从而阐明粘保护剂治疗骨性关节炎的可能机制。方法:实验于2006-03/11在华中科技大学附属协和医院骨科实验室完成。①实验材料:新鲜狗尸体4具,取肱骨头附近的全厚软骨以及滑膜组织。透明质酸钠购于中国山东正大福瑞达制药有限公司产品。②实验干预和分组:以100μg/L的白细胞介素1β与软骨滑膜联合培养。将0.2,1,2g/L透明质酸加入模型中得到3组透明质酸组,只含白细胞介素1β为阳性对照组,只含培养液为阴性对照组。③实验评估:每3天收集1次培养皿中的溶液标本,3,6,20d收集培养皿中的软骨滑膜标本,行生化和免疫组织化学检查。结果:①溶液标本与组织标本聚氨基葡萄糖检测结果:第3,6天溶液标本中透明质酸组高于阴性对照组(P<0.05);第20天时3种剂量透明质酸组溶液中聚氨基葡萄糖低于阳性对照组(P<0.05)。②溶液标本中前列腺素E2、基质金属蛋白酶3、含氮产物检测结果:第3天时阳性对照组基质金属蛋白酶3浓度高于阴性对照组(P<0.05),第20天,1g/L,2g/L透明质酸组基质金属蛋白酶3浓度较阳性组低[(1.289±2.122),(0.458±0.454),(1.425±0.211)μg/L,P<0.05],第3天时阳性对照组前列腺素E2浓度明显高于阴性对照组(P<0.05),第6天,0.2g/L,1g/L透明质酸组含氮产物浓度低于阳性和阴性对照组[(1.288±0.280),(1.345±0.768),(2.234±0.570),(1.845±0.767)mmol/L(P<0.05)。结论:实验结果支持粘保护剂治疗骨性关节炎的两种机制,即透明质酸对软骨保护的生物学合成作用与透明质酸的炎性抑制反应。 相似文献
783.
Juqiang Han Xiang Zhang Jennie K-C Lau Kaili Fu Harry CH Lau Weiqi Xu Eagle SH Chu Huiyao Lan Jun Yu 《The Journal of pathology》2019,248(4):488-500
The role of macrophages in fibrosing steatohepatitis is largely unclear. We characterized the origin and molecular mechanisms of macrophages and its targeted therapy of fibrosing steatohepatitis. Fibrosing steatohepatitis was established in Alms1 mutant (foz/foz) and C57BL/6J wildtype mice fed high-fat/high-cholesterol or methionine- and choline-deficient diet. Bone marrow transplantation was performed to track the macrophage origin in fibrosing steatohepatitis. Macrophages were depleted using liposomal clodronate. Primary macrophages were isolated from bone marrow for adoptive transfer into mice. We found that macrophage infiltration is induced in two mouse models of fibrosing steatohepatitis and human nonalcoholic steatohepatitis-fibrosis patients. Bone marrow-derived macrophages (BMMs) contribute to the hepatic macrophage accumulation in experimental fibrosing steatohepatitis. Depletion of hepatic BMMs by liposomal clodronate during liver injury attenuated fibrosing steatohepatitis, whilst BMMs depletion after liver injury delayed the regression of fibrosing steatohepatitis. The pro-fibrotic effect of macrophages was associated with reduced activation of hepatic stellate cells (HSCs), collagen deposition and hepatic expression of key pro-fibrotic factors (TIMP1, TIMP2, and TGFβ1) and endoplasmic reticulum stress markers (GRP78, IRE1α, and PDI). Conversely, adoptive transfer of BMMs significantly aggravated fibrosing steatohepatitis. Moreover, macrophage-conditioned medium directly promoted the phenotypic transition of primary quiescent HSCs to activated HSCs; it enhanced activation and proliferation but decreased apoptosis of HSC cell lines (LX-2 and HSC-T6). The effect of BMMs in promoting fibrosing steatohepatitis was mediated by inducing key pro-fibrosis factors and signaling pathways including cytokine/chemokine, TGFβ and complement cascade as assessed by cDNA expression array. Complement 3a receptor (C3ar1) was a predominant effector of macrophage mediated fibrosing steatohepatitis. Knockout of C3ar1 in mice blunted development of fibrosing steatohepatitis. In conclusion, BMMs promoted the progression of fibrosing steatohepatitis during injury, whereas macrophages reduced fibrosing steatohepatitis in the recovery phase of liver injury. Increasing anti-fibrotic macrophages and decreasing pro-fibrotic macrophages are promising approaches for fibrosing steatohepatitis. © 2019 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland. 相似文献
784.
叶酸受体在许多恶性肿瘤细胞表面过度表达,而在正常细胞中则几乎不表达或只有少量表达。利用叶酸受体表达的特性,通过将叶酸修饰于药物载体表面,可使药物靶向输送至叶酸受体过度表达的肿瘤细胞中,从而避免对正常细胞产生毒性,提高药物疗效;而纳米给药系统因粒径较小等原因可使药物在肿瘤部位浓集。本文对近年来叶酸受体介导的靶向纳米给药系统进行了综述。 相似文献
785.
Human immunodeficiency virus-type 1 replication can be increased in peripheral blood of seropositive patients after influenza vaccination 总被引:18,自引:0,他引:18
O'Brien WA; Grovit-Ferbas K; Namazi A; Ovcak-Derzic S; Wang HJ; Park J; Yeramian C; Mao SH; Zack JA 《Blood》1995,86(3):1082-1089
Despite considerable evidence that cell activation enhances human immunodeficiency virus-type 1 (HIV-1) replication in vitro, there is very little data on the role of immune activation on in vivo HIV-1 replication. In this study, we examined the effect of influenza vaccination on HIV-1 replication in the peripheral blood of 20 study subjects, and in 14 control subjects who did not receive influenza vaccination. Blood was obtained from each subject on three occasions during the month before vaccination and again on three occasions during the following month. Over the study period, there was little change in levels of proviral DNA in peripheral blood mononuclear cells (PBMCs). However, peak PBMC viral RNA levels after influenza vaccination were significantly increased over the mean of prevaccination values. This change was not observed to the same extent in unvaccinated controls. Therefore, this is the first report showing that HIV-1 replication can increase in temporal association with influenza vaccination. Our results suggest that continued immunologic (antigenic) stimulation may result in increased virus load in vivo. To address the appropriateness of influenza vaccination in HIV-infected patients, expanded studies will be required to examine specific and generalized immune responses to vaccination, and differences in patient response based on disease stage. 相似文献
786.
Pathogenesis of B cell lymphoma in a patient with AIDS 总被引:5,自引:0,他引:5
Groopman JE; Sullivan JL; Mulder C; Ginsburg D; Orkin SH; O'Hara CJ; Falchuk K; Wong-Staal F; Gallo RC 《Blood》1986,67(3):612-615
Lymphoma occurs at increased frequency in patients with the acquired immunodeficiency syndrome (AIDS). We studied, using serologic and molecular techniques, one such lymphoma for (a) evidence of infection with human T lymphotropic virus, type III (HTLV-III), and Epstein-Barr virus (EBV), (b) monoclonal rearrangement of immunoglobulin and T cell receptor genes, and (c) rearrangement of the c-myc oncogene. Immunoglobulin and T cell receptor gene studies demonstrated that the tumor was of monoclonal B cell origin. Similar to cases of Burkitt's lymphoma unrelated to AIDS, there were DNA sequences in the lymphoma that hybridized to EBV-specific probes and demonstrated evidence of c- myc rearrangement. HTLV-III sequences were not detected in the malignant B cells. The pathogenesis of some B cell neoplasms in patients with the syndrome may involve transformation by EBV and deregulation of oncogene expression without direct infection of the malignant B cells by HTLV-III. 相似文献
787.
0 引言 缺血缺氧性脑损害是体外循环心内直视术后常见的并发症 ,是患者致死或致残的重要原因 . 1990 - 12 / 1997- 0 5 ,我科共发生心脏术后脑缺血缺氧性损害 16例 ,占同期体外循环心内直视手术的 0 .8% .就其临床特点及护理对策报告如下 .1 临床资料 本组 16 (男 10 ,女 6 )例 .年龄 0 .5~ 5 9(平均2 6 )岁 .其中室间隔缺损并重度肺动脉高压矫治术后 5例 ;房间隔缺损修补和法鲁四联症根治术后各 1例 ;二尖瓣置换及三尖瓣成形术后 3例 ;二尖瓣置换及 COX迷宫术后 1例 ;主动脉瓣二尖瓣置换术后 3例 ;二尖瓣成形及未闭动脉导管结扎术后… 相似文献
788.
789.
Non‐resolving pulmonary symptoms in a patient with SLE require evaluation to exclude rare pulmonary lesions, such as carcinoid tumors. 相似文献