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51.
Phosphorylcholine (PC) groups were grafted onto ammonia plasma-treated biaxially-oriented polypropylene (BOPP) surfaces, via (a) reductive amination of phosphorylcholine glyceraldehyde and (b) a two-step procedure involving the chemical amplification of surface amine groups with tris(2-aminoethyl amine) and subsequent reductive amination of phosphorylcholine glyceraldehyde. The occurrence of grafting was ascertained by X-ray photoelectron spectroscopy (XPS) and attenuated total reflectance Fourier-transform infrared (ATR-FT-IR) spectroscopy. The wettability of PC-modified surfaces was assessed by dynamic contact-angle measurements using the Wilhelmy plate method. Human U937 macrophages adhered and proliferated to a significantly larger extent on PC-modified surfaces, compared to unmodified or ammonia plasma-modified BOPP.  相似文献   
52.
Background: Despite years of research, the treatment of acute kidney injury (AKI) remains a significant challenge. Animal studies presented causal links between elevated regulatory T cell (Treg) response and better prognosis in AKI. Previous studies in mice and humans showed that TIM-3+ Treg cells were more potent than TIM-3- Treg cells. In this study, we investigated the role of TIM-3 in Treg in AKI patients.

Methods: Peripheral blood from AKI patients and healthy controls were gathered, and TIM-3+ Treg subset was examined.

Results: Compared to healthy controls, the AKI patients presented a significant upregulation in the frequency of circulating CD4+CD25+ T cells; however, the majority of this increase was from the CD4+CD25+TIM-3- subset, and the frequency of CD4+CD25+TIM-3+ T cells was downregulated in AKI patients. In both healthy controls and AKI patients, the CD4+CD25+TIM-3+ T cells expressed higher levels of Foxp3, and were more potent at expressing LFA-1, LAG-3, CTLA-4, IL-10 and TGF-β. In addition, the CD4+CD25+TIM-3+ T cells from both healthy controls and AKI patients presented higher capacity to suppress CD4+CD25- T cell proliferation than the CD4+CD25+TIM-3- T cells. Interestingly, the total CD4+CD25+ T cells from AKI patients presented significantly lower inhibitory capacity than those from healthy controls, indicating that the low frequency of CD4+CD25+TIM-3+ T cells was restricting the efficacy of the Treg responses in AKI patients.

Conclusions: We demonstrated that TIM-3 downregulation impaired the function of Treg cells in AKI. The therapeutic potential of CD4+CD25+TIM-3+ T cells in AKI should be investigated in future studies.  相似文献   

53.
Current high-throughput approaches to the analysis of PCR products are based primarily on electrophoretic separation and laser-excited fluorescence detection. We show that capillary array electrophoresis can be applied to HIV-1 diagnosis and D1S80 VNTR genetic typing based simply on UV absorption detection. The additive contribution of each base pair to the total absorption signal provides adequate detection sensitivity for analyzing most PCR products. Not only is the use of specialized and potentially toxic fluorescent labels eliminated, but also the complexity and cost of the instrumentation are greatly reduced.  相似文献   
54.
55.
J H Gong  H Renz  M Nain  D Gemsa 《Immunobiology》1988,177(4-5):339-351
Peritoneal macrophages from DBA/2 mice, elicited by injection of Corynebacterium parvum (C.p.), were in vitro activated to Eb tumor cytostasis by incubation with tumor-induced ascites that was harvested 7 days after intraperitoneal Eb injection. The active cytostasis-mediating compound was found to be interleukin 1 (IL 1). When tumor ascites was fractionated according to molecular weight size, the most active IL 1-inducing fraction was found to comprise molecules of greater than 100,000 daltons. The data show that tumor-bearing hosts are capable of producing compounds that induce a high IL 1 secretion which may enable macrophages to mount an antiproliferative effect against tumor cells.  相似文献   
56.
淋巴结血管内T细胞淋巴瘤1例报道及文献复习   总被引:1,自引:0,他引:1  
目的 探讨血管内淋巴瘤 (IVL)的临床病理特征。方法 对 1例腹股沟淋巴结IVL临床、病理组织学及免疫表型进行观察分析并复习文献。结果 男性 31岁 ,不明原因高热伴消瘦 5 0天 ,右腹股沟直径 1cm淋巴结 1枚 ,B超示肝脏轻度增大 ,血LDH明显升高伴ESR及转氨酶轻度升高 ,外周血WBC 3 3× 10 7/L ,骨髓像、多种病原及各肿瘤相关抗原检测均无异常。病理活检 :腹股沟淋巴结大部分破坏 ,代之以大量扩张的中小血管 ,腔内充满大量异型淋巴样细胞 ,局部伴管壁、管周浸润并累及结外脂肪组织。瘤细胞免疫表型CD4 5、CD4 5RO、CD3阳性 ,CK、CD6 8、CD79α、CD2 0均阴性 ,血管壁及内皮细胞CD31、CD34阳性。行CHOP化疗后症状缓解 ,现仍在随访中。结论 IVL是一罕见的非霍奇金淋巴瘤 ,好发于中枢神经系统及皮肤 ,其他部位少见 ,绝大数为B细胞型 ,T型罕见 ,以浅表淋巴结活检确诊者尚无报道。临床表现有一定提示性 ,确诊靠组织病理学检查 ,部分病例对化疗敏感 ,但多数病例预后差  相似文献   
57.
音猬因子的功能受体斑片在培养神经干细胞中的表达   总被引:1,自引:0,他引:1  
许汉鹏  胡沛臻  苟琳  张萍  鞠躬 《解剖学报》2002,33(6):561-565
目的 观察在培养的神经干细胞内是否有发育调控分子———音猬因子 (sonichedgehog)功能受体———斑片 (patched)表达。 方法 神经干细胞克隆在体外培养传代后 ,用patched的特异性引物对培养的神经干细胞进行RT PCR分析 ,PCR产物经克隆测序后 ,用地高辛标记克隆的探针 ,对神经干细胞进行原位杂交分析。 结果 神经干细胞克隆内大量的细胞均可表达sonichedgehog的功能受体patched ,patched阳性细胞间未见明显差别 ,克隆边缘与中央的patched分布也未见明显差别。 结论 sonichedgehog信号传导路可能在神经干细胞的增殖与分化过程中起重要作用。  相似文献   
58.
Alpha-methylacyl-CoA racemase (AMACR)/P504S is an enzyme involved in the metabolism of branched-chain fatty acids. Little is known about correlation of AMACR expression with colorectal carcinoma (CRC) differentiation and prognosis. We investigated the expression of AMACR in 106 cases of primary CRC, and in 47 lymph nodes with metastatic CRC by immunohistochemical analysis. These cases were divided into 3 groups according to the histologic differentiation of the primary tumors. group A included 50 cases of histologically well and moderately differentiated CRCs, 20 of these with lymph node metastasis; group B included 23 cases of well and moderately differentiated CRCs, histologically similar to group A, except these tumors had small foci (less than 20%) of high-grade carcinoma, and 10 of these had lymph node metastasis; group C included 33 cases of poorly differentiated adenocarcinoma and undifferentiated carcinoma, 17 with lymph node metastasis. The results showed the overall positive rates of expression in primary and metastatic CRCs were 59.4% and 46.8%, respectively. Expression in groups A (76.0%) and B (69.6%) was much higher than that in group C (27.3%). In group B, although overexpression of AMACR in primary tumors was similar to that of group A, it was only seen in 30.0% of group B metastatic tumors, which was similar to the rate of expression in group C (23.5%). In contrast, rates of expression in group A primary and metastatic tumors were similar (80.0% and 75.0%). Positive staining for AMACR in benign epithelium adjacent to tumor was rare (<2%). No relation was found between AMACR expression and overall survival. Our findings support the view that the expression of AMACR in CRC is correlated with tumor differentiation.  相似文献   
59.
Poly(enaminonitriles) containing flexible alkyl ether units were prepared by reacting p-bis(1-chloro-2,2-dicyanovinyl)benzene with various α,ω-bis(4-aminophenoxy)alkanes in N-methyl-2-pyrrolidone (NMP). All the polymers are soluble in polar aprotic solvents such as N,N-dimethylformamide (DMF), dimethyl sulfoxide (DMSO), N,N-dimethylacetamide (DMAc) and NMP as well as in common organic solvents such as tetrahydrofuran and acetone. High molecular weight polymers possessing inherent viscosities in the range of 0.82–1.20 dL/g were obtained and tough films were cast from a DMF solution. They showed a large exotherm around 340°C attributable to the chemical changes of the dicyanovinyl group. Thermogravimetric analyses exhibited a good thermal stability with a 10% weight loss around 450°C and 73–88% residual weight at 500°C under nitrogen.  相似文献   
60.
7,8-Dihydroxyflavone (DHF) is a naturally occurring flavonoid that has been reported to protect against a variety of pathologies. Chronic administration of DHF prevents high-fat diet (HFD)-induced obesity in female, but not male, mice. However, the mechanisms underlying this sexual dimorphism have not been elucidated. We have discovered that oral DHF supplementation significantly attenuates fat mass, hepatic lipid accumulation, and adipose tissue inflammation in female mice. In contrast, male mice were not protected from adiposity, and had a paradoxical worsening of hepatic lipid accumulation and adipose tissue inflammation upon DHF supplementation. Consistent with these sexually dimorphic effects on body weight and metabolic health, 7,8-DHF induced early and stable remodeling of the female intestinal microbiome. DHF supplementation significantly increased gut microbial diversity, and suppressed potentially detrimental bacteria, particularly Desulfovibrionaceae, which are pro-inflammatory and positively associated with obesity and inflammation. Changes in the female gut microbiome preceded alterations in body weights, and in silico analyses indicated that these early microbial changes were highly predictive of subsequent weight gain in female mice. While some alterations in the intestinal microbiome were also observed in male DHF-supplemented mice, these changes were distinct from those in females and, importantly, were not predictive of subsequent body weight changes in male animals. The temporality of microbial changes preceding alterations in body weight in female mice suggests a role for the gut microbiome in mediating the sexually dimorphic effects of DHF on body weight. Given the significant clinical interest in this flavonoid across a wide range of pathologies, further elucidation of these sexually dimorphic effects will aid the development of effective clinical therapies.  相似文献   
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