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951.
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953.
Solitary pulmonary capillary hemangioma (SPCH) is a rare benign lung tumor that must be distinguished from small and early lung cancers. Here, we report a case of SPCH for which we performed frozen section diagnosis. The patient was a 55‐year‐old Japanese woman. Five years before the operation, mixed ground‐glass opacity was detected by computed tomography in the left posterior basal segment of the lower lobe (S10). Because the interior tumor density of the ground‐glass opacity increased slightly, video‐assisted thoracic surgery wedge resection was performed. Frozen section diagnosis revealed a benign tumor without proliferation of atypical epithelial cells. The tumor had narrow alveolar lumens, thickened alveolar septa and a clear boundary separating it from normal lung tissue. The proliferated lumens varied in size and were lined with single layers of flat cells. After the operation, immunohistochemical staining of a paraffin section revealed that the thickened alveolar septa resulted from the proliferation of capillary vessels, the flat cells of which were positive for CD31 and CD34 and negative for podoplanin; the tumor was diagnosed as SPCH. Here, we discuss the pathological features of SPCH on frozen sections with reference to this case and review previous related reports.  相似文献   
954.
《HIV clinical trials》2013,14(4):287-295
Abstract

Purpose: To investigate whether TT virus (TTV) viral load may be used as a surrogate marker for functional immune reconstitution in HIV-infected patients receiving highly active antiretroviral therapy (HAART). Method: Fifteen protease inhibitor-naÏve HIV-infected patients were included in a longitudinal study. From each patient, three serum samples taken before HAART initiation and three samples taken during HAART were analyzed. TTV was detected by polymerase chain reaction (PCR) and was quantitated by competitive PCR. TTV viral heterogeneity was determined by restriction fragment length polymorphisms (RFLPs) and sequencing. Results: All 15 HIV-infected patients were TTV positive. No significant change in HIV RNA or TTV viral load was observed at the three time points before HAART initiation. Even though HAART lead to an immediate and significant reduction in HIV RNA (p = .0001), a significant reduction in TTV viral load (p = .0002) was not observed until after 3-5 months of HAART. Four patients did not have an increase in CD4+ T cell count after 1 year of HAART; however, a decrease in TTV viral load was still observed, and three of these patients had a reduction in HIV RNA. RFLPs and sequencing revealed that TTV is represented as a heterogeneous population of virus in HIV-infected patients. Conclusion: This pilot study suggests that HAART leads to improved immunological responses, even in patients who do not have an increase in CD4+ T cell counts. We propose that the change in TTV viral load may be useful in the evaluation of cellular immune response at a functional level in HIV-infected patients who receive HAART.  相似文献   
955.
Abstract

The comparative prognostic importance of latest plasma HIV RNA levels (viral loads) and CD4+ cell counts among patients prescribed highly active antiretroviral therapy (HAART) has not been well characterized. Method: We assessed the prognostic value of latest CD4+ cell counts and latest viral loads for progression to AIDS or death and explored their interaction among 432 HIV-infected persons with advanced HIV who were prescribed a protease inhibitor (PI) as their first HAART regimen. Results: Pre-HAART median CD4+ cell count and viral load were 41 cells/mm3 and 126,331 copies/mL, respectively. After 12 months of HAART, the median CD4+ cell count was 154 cells/mm3; 39% of patients had a viral load of 400 copies/mL or lower. Over a median follow-up of 33 months, 109 (25%) of the 432 patients experienced an AIDS event or died. The hazard ratio for AIDS or death for those with latest CD4+ cell count <50 cells/mm3 versus ≥200 cells/mm3 was 13.9 (95% CI 6.5 to 29.7) without adjustment for latest viral load measurements and 9.5 (95% CI 4.0 to 22.5) after adjustment for latest viral load. In contrast, the hazard ratio for AIDS or death for those with viral load ≥100,000 versus <400 copies/mL was 4.2 (95% CI 2.3 to 7.7) without adjustment for latest CD4+ level and 1.2 (95% CI 0.6 to 2.4) with adjustment for latest CD4+ cell count. Conclusion: We conclude that when latest CD4+ cell count and viral load are considered separately, both are significantly related to AIDS or death; when these markers are jointly considered, the association of viral load with AIDS or death is substantially diminished. Latest CD4+ levels are more strongly related to AIDS or death than latest viral load levels in patients on HAART.  相似文献   
956.
957.
Oral lichen planus (OLP) is a chronic inflammatory disease displaying ultrastructural disturbances in epithelial hemidesmosomes. The expression of several key hemidesmosomal components in OLP as well as in normal buccal mucosa is, however, unknown. The aim of the study was therefore to examine intracellular and extracellular components involved in hemidesmosomal attachment, in OLP (n = 20) and in normal buccal mucosa (n = 10), by immunofluorescence. In normal buccal mucosa, laminin-α3γ2, integrin-α6β4, CD151, collagen α-1(XVII) chain, and dystonin showed linear expression along the basal membrane, indicating the presence of type I hemidesmosomes. Plectin stained most epithelial cell membranes and remained unphosphorylated at S4642. In OLP, most hemidesmosomal molecules examined showed disturbed expression consisting of discontinuous increases, apicolateral location, and/or intracellular accumulation. Plectin showed S4642-phosphorylation at the basement membrane, and deposits of laminin-α3 and laminin-γ2 were found within the connective tissue. The disturbed expression of hemidesmosomal proteins in OLP indicates deficient attachment of the basal cell layer, which can contribute to detachment and cell death of basal keratinocytes seen in the disease.  相似文献   
958.
目的探讨外源性白细胞介素(interleukin,IL)35对口腔扁平苔藓(oral lichen planus,OLP)患者外周血中辅助性T细胞17(helper T cell 17,Th17)与调节性T细胞(regulatory T cell,Treg)平衡的影响。方法选取2016年10至12月就诊于贵州医科大学附属医院口腔内科黏膜专科门诊的12例OLP患者外周血(OLP组)(男性1例,女性11例,26~68岁;其中非糜烂型OLP4例,糜烂型OLP 8例),同期收集贵州医科大学附属医院体检中心的13名健康人外周血(健康对照组)(男性1名,女性12名,20~68岁),无菌提取两组外周血单个核细胞,流式细胞术(flow cytometry,FCM)分选外周血CD4+T细胞,采用实时荧光定量PCR(quantitative real-time PCR,qPCR)检测两组外周血CD4+T细胞中Th17、Treg细胞特异转录因子维甲酸相关孤核受体γt(retinoic acid receptor-related orphan receptorγt,RORγt)、叉头状转录因子(forkhead box3,Foxp3)mRNA表达水平;将OLP患者外周血分选出的CD4+T细胞分为实验组与对照组,实验组加入重组人IL-35蛋白(recombinant human IL-35,rhIL-35),对照组加入等体积磷酸盐缓冲液,分别进行细胞体外培养,收集培养结束后的细胞,qPCR检测上述因子的表达水平。结果OLP组CD4+T细胞中Foxp3、RORγt mRNA的相对表达量[M(Q25,Q75)分别为0.15(0.09,0.30)和1.04(0.45,2.15)]均显著大于健康对照组[分别为0.04(0.02,0.06)和0.10(0.05,0.11)](Z=-4.134,P<0.01;Z=-3.699,P<0.01)。OLP组RORγt/Foxp3 mRNA比值[6.22(3.67,15.34)]显著大于健康对照组[2.50(1.24,5.23)](Z=-2.665,P=0.007)。OLP患者外周血实验组CD4+T细胞Foxp3 mRNA相对表达量[0.40(0.21,1.22)]显著大于对照组[0.15(0.11,0.26)](Z=-2.510,P=0.012),两组RORγt mRNA表达差异无统计学意义(P>0.05),实验组RORγt/Foxp3 mRNA比值[3.44(1.55,8.16)]显著小于对照组[6.22(4.43,12.21)](Z=-2.746,P=0.006)。结论OLP患者外周血中存在Th17细胞占优势的Th17/Treg平衡异常,外源性IL-35可通过促进Treg细胞扩增,实现对OLP患者外周血中Th17/Treg平衡的调节。  相似文献   
959.
目的分析外周血Th1/Th2细胞因子在循环毒毒蛇咬患者中的表达,探讨其在病情评估中的意义。方法收集2016年3月至2017年10月循环毒毒蛇咬伤患者108例,根据国际蛇伤诊断标准分为轻度蛇咬伤组82例与重度蛇咬伤组26例,另外选择同期体检健康者30例为对照组。通过流式细胞术检测并比较分析各组患者T淋巴细胞亚群的分布情况及外周血Th1/Th2细胞因子的表达。结果与对照组比较,重度蛇咬伤组CD3^+、CD4^+T淋巴细胞水平偏低(P<0.01);细胞因子IL-4、IL-6、IL-10、TNF-α表达水平升高(P<0.05)。蛇咬伤组两两比较,重度蛇咬伤组CD3^+、CD4^+T淋巴细胞水平低于轻度蛇咬伤组(P<0.05),IL-4、IL-6、TNF-α表达水平均高于轻度蛇咬伤组(P<0.05)。结论循环毒毒蛇咬伤患者中存在有明显的T淋巴细胞数量的改变和Th1/Th2细胞因子表达紊乱,且与病情严重程度相关。  相似文献   
960.
Cartilage‐derived mesenchymal stem cells (MSCs) have been isolated with different methods. In this study lateral and medial femoral condyles were respectively collected from patients with late‐stage osteoarthritis during the total knee arthroplasty. After digestion of the cartilage tissues with type II collagenase and analysis by fluorescence‐activated cell sorting (FACS) with CD146, a chondroprogenitor cell sub‐population were isolated and purified. The expression of other MSC‐associated markers in the CD146+ chondroprogenitors was analyzed by flow cytometry. Multi‐lineage differentiation capacity of CD146+ chondroprogenitors was compared with that of unsorted chondrocytes and adipose‐derived MSCs (ADMSCs). Higher percentage of CD146+ chondroprogenitors isolated from the medial femoral condyles was observed than that from the lateral. CD146+ chondroprogenitors expressed high levels of MSC‐specific surface antigens, and showed higher chondrogenesis capacity than ADMSCs and unsorted chondrocytes in a 3D cell pellet culture model. Thus CD146 might be a new cell surface marker for cartilage progenitor cell population in the late‐stage osteoarthritis. © 2014 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:84–91, 2015.  相似文献   
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