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991.
Braira Wahid Khadija Shami Salman A. Joiya Sevilay E. G. Özuyar Muhammad Idrees 《Journal of medical virology》2020,92(12):3868-3870
The recent development of direct-acting antiviral (DAA) drugs has revolutionized the area of hepatitis C virus (HCV) therapeutics but the efficacy and clinical outcome of interferon (IFN)-free therapy have not been extensively studied yet. We observed a dramatic increase in hypothyroidism among patients treated with sofosbuvir, IFN, and ribavirin. This is the first prospective study of the thyroid dysfunction in DAA drugs treated patients. This study compared the risk of hypothyroidism in two different groups of HCV patients treated with different DAA drugs regimens that were sofosbuvir + pegylated-IFN-α + ribavirin and sofosbuvir + daclatasvir + ribavirin. Our findings highlight the periodic screening of serum thyroid-stimulating hormone and T4 levels in HCV infected patients during the treatment and posttreatment. 相似文献
992.
Flavia Balena MD Davide F. Bavaro MD Anna Volpe BMed Biol Antonella Lagioia BMed Biol Gioacchino Angarano MD Laura Monno MD Annalisa Saracino MD PhD 《Journal of medical virology》2020,92(12):3271-3278
HIV-1 V2 domain binds α4β7, which assists lymphocyte homing to gut-associated lymphoid tissue. This triggers bacterial translocation, thus contributing to immune activation. We investigated whether variability of V2 179-181binding site could influence plasma levels of lipopolysaccharide (LPS) and soluble cluster of differentiation 14 (sCD14), markers of microbial translocation/immune activation. HIV gp120 sequences from antiretroviral naïve patients were analyzed for V2 tripeptide composition, length, net charge, and potential N-linked-glycosylation sites. LPS and sCD14 plasma levels were quantified. Clinical/immuno-virologic data were retrieved. Overall, 174 subjects were enrolled, 8% with acute infection, 71% harboring a subtype B. LDV179-181 was detected in 41% and LDI in 27%. No difference was observed between levels of LPS or sCD14 according to different mimotopes or according to other sequence characteristics. By multivariable analysis, only acute infection was significantly associated with higher sCD14 levels. In conclusion, no association was observed between V2 tripeptide composition and extent of bacterial translocation/immune activation. 相似文献
993.
Peter Brøgger Lars H. Blom Stine Simonsen Jacob P. Thyssen Lone Skov 《Scandinavian journal of immunology》2020,91(1):e12835
Atopic dermatitis (AD) is a chronic and relapsing inflammatory skin disease. Molecular characterization of AD shows an underlying inflammation with tissue infiltration of T helper (TH) 2 cells and increased IL-4 and IL-13. The multifaceted roles of IL-4 and IL-13 in allergic disease development make IL-4Rα an attractive target for treatment strategies, and a neutralizing monoclonal antibody which antagonizes the effects of both IL-4 and IL-13 by blocking the interaction site found in the IL-4 receptor subunit α (IL-4Rα) has been successfully used to treat patients with moderate-to-severe AD. To elucidate the effects of IL-4Rα blockade on the cellular level, we used flow cytometry to examine cytokine production after antigen stimulation in human T cells from patients with AD (n = 12) and healthy controls (n = 6). The cells were stimulated with and without a neutralizing monoclonal antibody against IL-4Rα. Our results indicate that blocking IL-4Rα prohibits IL-4 signalling and IL-13 signalling and thereby TH2 differentiation followed by an upregulation of interferon-γ-producing cells. 相似文献
994.
《Pathology, research and practice》2020,216(4):152853
BackgroundLong non-coding RNA (lncRNA) TMPO antisense RNA 1 (TMPO-AS1) is reported to be oncogenic in prostate cancer and lung cancer. This study aims to investigate the expression and biological function of it in retinoblastoma (RB), and explore its regulatory role for miR-199a-5p and hypoxia-inducible factor-1α (HIF-1α).MethodsPaired RB samples were collected, and the expression levels of TMPO-AS1, miR-199a-5p and HIF-1α were examined by quantitative real-time polymerase chain reaction (qRT-PCR); TMPO-AS1 overexpressing plasmids and TMPO-AS1 shRNA were transfected into HXO-RB44 and SO-Rb50 cell lines respectively, and then proliferation, migration and invasion of RB cells were detected by CCK-8 assay and Transwell method. qRT-PCR and western blot were used to analyze the regulatory function of TMPO-AS1 on miR-199a-5p and HIF-1α; luciferase reporter gene assay was used to determine the regulatory relationship between miR-199a-5p and TMPO-AS1.ResultsTMPO-AS1 was significantly up-regulated in cancerous tissues of RB samples (relatively expression: 2.97 vs 3.93, p < 0.001), negatively correlated with miR-199a-5p (r=-0.4813, p < 0.01). There was one binding site on TMPO-AS1 for miR-199a-5p. After transfection of TMPO-AS1 shRNAs into RB cells, the proliferation, migration and invasion of cancer cells was significantly inhibited, while TMPO-AS1 had opposite effects; TMPO-AS1 was also demonstrated to regulate the expression of HIF-1α on both mRNA and protein levels via negatively regulating miR-199a-5p.ConclusionTMPO-AS1 is abnormally up-regulated in RB tissues, and it can modulate the proliferation and migration of RB cells. It has the potential to be the “ceRNA” to regulate HIF-1α expression by sponging miR-199a-5p. 相似文献
995.
目的探讨胎盘粘连植入组织和人胎盘滋养层细胞中血管细胞黏附分子-1(vascular cell adhesion molecule-1,VCAM-1)的表达及其与侵入性胎盘疾病的相关性。方法采用酶联免疫吸附试验检测2017年9月至2018年9月期间我院收治的20例产妇静脉血中可溶性VCAM-1(sVCAM-1)的表达水平,根据sVCAM-1的平均值将另外随机选取的200例产妇分为高表达组和低表达组,计算两组侵入性胎盘发生率。采用免疫组化染色、实时定量PCR和Western blot检测40例侵入性胎盘组织和40例正常胎盘组织中的VCAM-1、TNF-α、NF-κB p65和IκBα表达。应用20 ng/mL的TNF-α处理人胎盘滋养层HTR8/SVneo细胞系后检测细胞中VCAM-1、TNF-α、NF-κB p65和IκBα的表达。结果20例健康产妇静脉血中的VCAM-1平均水平为36.32±3.25 ng/mL。高表达组的侵入性胎盘发生率(6.98%)显著高于低表达组(0.64%)(χ^2=0.922,P=0.009)。实时定量RT-PCR和Western blot结果表明,与对照组相比,侵入性胎盘组VCAM-1的mRNA和蛋白表达水平显著升高。免疫染色显示VCAM-1蛋白主要在滋养细胞的细胞质和膜中表达,侵入性胎盘组的VCAM-1阳性率(72.50%)显著高于对照组(17.50%)(Z=-5.063,P<0.001)。与对照组相比,侵入性胎盘组的TNF-α和NF-κB p65表达水平显著升高,而IκBα表达水平显著降低(P<0.05)。与未用TNF-α处理(0 ng/mL)的HTR8/SVneo细胞相比,应用20 ng/mL浓度的TNF-α处理细胞1周后,细胞中的NF-κB p65和VCAM-1表达水平显著升高,而IκBα表达水平显著降低(P<0.05)。结论VCAM-1在侵入性胎盘产妇血液和胎盘组织中均为高表达模式。VCAM-1的活化至少部分依赖于TNF-α、NF-κB信号通路的激活,从而诱导其在滋养细胞中高表达并引起过度侵袭,导致侵入性胎盘的发生。 相似文献
996.
目的探索miR-138-5p与缺氧诱导因子-1α(HIF-1α)对人白血病K562细胞增殖和侵袭转移的影响。方法以体外培养的人白血病K562细胞为研究对象,将其分为K562组、miR-138 mimic组、pc-HIF-1α组和mimic+pc-HIF-1α组。荧光素酶报告实验确认miR-138-5p与HIF-1α的靶向关系;qRT-PCR法检测miR-138-5p和HIF-1α的mRNA水平;Western blot检测HIF-1α的蛋白水平;CCK-8检测细胞存活率;Transwell检测细胞侵袭能力;划痕实验检测细胞迁移能力;Western blot检测增殖和上皮间质转化(EMT)相关蛋白表达水平。结果miR-138-5p能靶向HIF-1α,与K562组相比,miR-138 mimic组HIF-1α的mRNA和蛋白水平均显著较低(P<0.01),而pc-HIF-1α组HIF-1α的蛋白水平则显著较高(P<0.01);同时,与pc-HIF-1α组相比,mimic+pc-HIF-1α组HIF-1α的蛋白表达显著较低(P<0.01)。与K562组相比,miR-138 mimic组细胞增殖倍数、细胞迁移和侵袭能力均显著较低(P<0.01),pc-HIF-1α组则显著较高(P<0.01);与pc-HIF-1α组相比,mimic+pc-HIF-1α组细胞增殖倍数、细胞迁移和侵袭能力均显著较低(P<0.01)。同时,mimic+pc-HIF-1α能部分逆转pc-HIF-1α对肿瘤细胞增殖和EMT能力的上调作用(P<0.01)。结论miR-138-5p可通过靶向HIF-1α,进而降低人白血病K652细胞增殖和侵袭转移能力。 相似文献
997.
背景:缺血性股骨头坏死以股骨头血液供应不足为主要病因。髓芯减压术属于临床常用治疗手段,有研究发现采用自体骨髓干细胞移植能较好地改善髋关节功能,二者联合应用可促使患者尽早恢复。
目的:观察自体骨髓干细胞移植联合髓芯减压治疗早期缺血性股骨头坏死的疗效以及血清成纤维细胞生长因子2、缺氧诱导因子1α、血管内皮生长因子水平。
方法:选取2016年1月至2018年1月收治的62例早期缺血性股骨头坏死患者进行研究,参照随机数字表法分为研究组(n=31)和对照组(n=31),对照组给予细针多孔道髓芯减压术治疗,研究组在对照组基础上联合自体骨髓干细胞移植治疗,观察两组患者治疗前后Harris评分、目测类比评分、血清成纤维细胞生长因子2、缺氧诱导因子1α、血管内皮生长因子水平及不良反应发生情况。
结果与结论:①两组患者治疗后3,6,12个月Harris评分均高于治疗前(P < 0.05),研究组高于对照组(P < 0.05);②两组患者治疗后3,6,12个月目测类比评分均低于治疗前(P < 0.05),研究组治疗后3,6个月目测类比评分低于对照组(P < 0.05);③两组患者治疗后3,6,12个月血清成纤维细胞生长因子2水平高于治疗前(P < 0.05),研究组高于对照组(P < 0.05);缺氧诱导因子1α、血管内皮生长因子水平明显低于治疗前(P < 0.05),研究组低于对照组(P < 0.05);④两组患者治疗后不良反应发生率比较差异无显著性意义(P > 0.05);⑤结果表明自体骨髓干细胞移植联合髓芯减压治疗早期缺血性股骨头坏死,可有效改善髋关节功能,促进股骨头坏死区修复,减轻患者疼痛,提高成纤维细胞生长因子2水平,降低缺氧诱导因子1α、血管内皮生长因子水平。
ORCID: 0000-0001-9884-7530(张景义)
中国组织工程研究杂志出版内容重点:干细胞;骨髓干细胞;造血干细胞;脂肪干细胞;肿瘤干细胞;胚胎干细胞;脐带脐血干细胞;干细胞诱导;干细胞分化;组织工程 相似文献
998.
The abysmal success rate of anticancer drugs in clinical trials, is in part, attributable to discordance between cultured cancer cells and patient tumors. While tumors in vivo, display a lower mitotic index, patient tumors portray much higher centrosomal aberrations, relative to in vitro cultured cells. The microenvironment too differs considerably between the in vitro and in vivo scenarios. Notably, another hallmark of cancer, hypoxia, is not recapitulated in cell lines cultured under normoxic conditions. These observations raise the possibility that hypoxia may be the missing link that explains the discordance between cell biological phenomena in vitro versus physiological conditions. Further, the interplay between hypoxia and centrosome amplification (CA) is relatively understudied. Recent research from our laboratory, geared toward examining the biological link between the two, has uncovered that hypoxia induces the expression of proteins (Plk4, Aurora A, Cyclin D) implicated in CA, in a hypoxia-inducible factor 1α (HIF-1α)-dependent context. Our studies evidence that hypoxia fuels CA that underlie intratumoral heterogeneity and metastatic potential of cancer cells. Given the advent of HIF-1α inhibitors, this research has ramifications in aiding patient risk stratification and designing new cancer drug therapies to facilitate clinical decision-making. 相似文献
999.
Fabien Dalonneau Xi Qiu Liu Rabia Sadir Jorge Almodovar Hichem C. Mertani Franz Bruckert Corinne Albiges-Rizo Marianne Weidenhaupt Hugues Lortat-Jacob Catherine Picart 《Biomaterials》2014
Several chemokines are important in muscle myogenesis and in the recruitment of muscle precursors during muscle regeneration. Among these, the SDF-1α chemokine (CXCL12) is a potent chemoattractant known to be involved in muscle repair. SDF-1α was loaded in polyelectrolyte multilayer films made of poly(l-lysine) and hyaluronan to be delivered locally to myoblast cells in a matrix-bound manner. The adsorbed amounts of SDF-1α were tuned over a large range from 100 ng/cm2 to 5 μg/cm2, depending on the initial concentration of SDF-1α in solution, its pH, and on the film crosslinking extent. Matrix-bound SDF-1α induced a striking increase in myoblast spreading, which was revealed when it was delivered from weakly crosslinked films. It also significantly enhanced cell migration in a dose-dependent manner, which again depended on its presentation by the biopolymeric film. The low-crosslinked film was the most efficient in boosting cell migration. Furthermore, matrix-bound SDF-1α also increased the expression of myogenic markers but the fusion index decreased in a dose-dependent manner with the adsorbed amount of SDF-1α. At high adsorbed amounts of SDF-1α, a large number of Troponin T-positive cells had only one nucleus. Overall, this work reveals the importance of the presentation mode of SDF-1α to emphasize its effect on myogenic processes. These films may be further used to provide insight into the role of SDF-1α presented by a biomaterial in physiological or pathological processes. 相似文献
1000.
The Fc region of IgG antibodies, important for effector functions such as antibody-dependent cell-mediated cytotoxicity, antibody-dependent cellular phagocytosis and complement activation, contains an oligosaccharide moiety covalently attached to each CH2 domain. The oligosaccharide not only orients the CH2 domains but plays an important role in influencing IgG effector function, and engineering the IgG-Fc oligosaccharide moiety is an important aspect in the design of therapeutic monoclonal IgG antibodies. Recently we reported the crystal structure of glycosylated IgG4-Fc, revealing structural features that could explain the anti-inflammatory biological properties of IgG4 compared with IgG1. We now report the crystal structure of enzymatically deglycosylated IgG4-Fc, derived from human serum, at 2.7 Å resolution. Intermolecular CH2-CH2 domain interactions partially bury the CH2 domain surface that would otherwise be exposed by the absence of oligosaccharide, and two Fc molecules are interlocked in a symmetric, open conformation. The conformation of the CH2 domain DE loop, to which oligosaccharide is attached, is altered in the absence of carbohydrate. Furthermore, the CH2 domain FG loop, important for Fcγ receptor and C1q binding, adopts two different conformations. One loop conformation is unique to IgG4 and would disrupt binding, consistent with IgG4's anti-inflammatory properties. The second is similar to the conserved conformation found in IgG1, suggesting that in contrast to IgG1, the IgG4 CH2 FG loop is dynamic. Finally, crystal packing reveals a hexameric arrangement of IgG4-Fc molecules, providing further clues about the interaction between C1q and IgG. 相似文献