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71.
Zika virus (ZIKV) RNA has been found to remain in human semen for up to one year after infection, but the presence of Flavivirus antigens in the different compartments of semen has been largely unexplored. Following the introduction of ZIKV in Nicaragua (2016), a prospective study of patients with clinical symptoms consistent with ZIKV was conducted in León to investigate virus shedding in different fluids. ZIKV infection was confirmed in 16 male subjects (≥18 years of age) by RT-qPCR in either blood, saliva or urine. Of these, three provided semen samples at 7, 14, 21, 28, 60 and 180 days postsymptom onset (DPSO) for Flavivirus antigens and RNA studies. These cases were compared with 19 asymptomatic controls. Flavivirus antigens were examined by immunofluorescence (IF) using the 4G2 Mabs, and confocal microscopy was used to explore fluorescence patterns. The three (100%) symptomatic subjects and 3 (16%) of the 19 asymptomatic subjects had Flavivirus antigens and viral RNA in the spermatozoa fraction. The percentage of IF Flavivirus-positive spermatozoa cells ranged from 1.9% to 25% in specimens from symptomatic subjects, as compared with 0.8% to 3.8% in specimens from asymptomatic controls. A marked IF-pattern in the cytoplasmic droplets and tail of the spermatozoa was observed. The sperm concentrations (45 × 106/mL vs. 63.5 × 106/mL, p = 0.041) and the total motility percentage (54% vs. 75%, p = 0.009) were significantly lower in specimens from ZIKV-positive than in those of ZIKV-negative. In conclusion, this study demonstrated the presence of Flavivirus antigens and RNA within a time frame of 28 DPSO in sperm cells of symptomatic and asymptomatic subjects during the ZIKV epidemic. These findings have implications for public health, in terms of nonarthropod-born, silent transmission facilitated by sperm cells and potential transmission from asymptomatic males to pregnant women, with consequences to the fetus.  相似文献   
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As some breast cancer‐related deaths can be attributed to the metastasis of cancer stem cells, chemotherapeutic agents targeting breast cancer stem cells are of interest as a potential treatment. Flavonoids that exhibit cytotoxicity on breast cancer stem cells have rarely been observed. Thus, the objective of this study was to measure potential cytotoxic effects of 42 different flavonoids on the human breast cancer stem‐like cell line, MCF7‐SC. The relationship between flavonoid structural properties and cytotoxicity has not been reported previously; therefore, we determined quantitative structure–activity relationships using both comparative molecular field analysis and comparative molecular similarity analysis. Further biological experiments including Western blot analysis, flow cytometry, and immunofluorescence microscopy were also conducted on the most cytotoxic 8‐chloroflavanone.  相似文献   
74.
The human interosseous membrane (IOM) is a fundamental stabilizer during forearm rotation. To investigate the dynamic aspects of forearm stability, we analyzed sensory nerve endings in the IOM. The distal oblique bundle (DOB), the distal accessory band (DAB), the central band (CB), the proximal accessory band (PAB), the dorsal oblique accessory cord (DOAC) and the proximal oblique cord (POC) were dissected from 11 human cadaver forearms. Sensory nerve endings were analyzed at two levels per specimen as total cell amount/mm2 after immunofluorescence staining with low-affinity neurotrophin receptor p75, protein gene product 9.5, S-100 protein and 4′,6-diamidino-2-phenylindole on an Apotome microscope, according to Freeman and Wyke’s classification. Sensory nerve endings were significantly more commonly found to be equally distributed throughout the structures, rather than being epifascicular, interstitial, or close to the insertion into bone (P ≤ 0.001, respectively). Free nerve endings were the predominant mechanoreceptor in all six structures, with highest density in the DOB, followed by the POC (P ≤ 0.0001, respectively). The DOB had the highest density of Pacini corpuscles. The DOAC and CB had the lowest amounts of sensory innervation. The high density of sensory corpuscles in the DOB, PAB and POC indicate that proprioceptive control of the compressive and directional muscular forces acting on the distal and proximal radioulnar joints is monitored by the DOB, PAB and POC, respectively, due to their closed proximity to both joints, whereas the central parts of the IOM act as structures of passive restraint.  相似文献   
75.
目的探讨磷脂酶A2受体1(PLA2R1)在肾脏穿刺的冷冻标本及石蜡标本中的表达,分析不同标本中阳性率的临床病理诊断意义。方法收集2013年1月~2019年2月江门市中心医院行肾脏穿刺患者的标本及临床病理资料,其中同时有肾活检冷冻标本及石蜡标本的患者215例,仅有石蜡标本的患者785例。分别利用免疫荧光及免疫组化法检测PLA2R1在肾活检冷冻和石蜡标本中的表达,并分析PLA2R1表达与临床病理特征的相关性。结果在215例冷冻标本中,PLA2R1阳性率为19.1%;在1000例石蜡标本中,PLA2R1阳性率为32.9%,两组中PLA2R1的阳性率差异有统计学意义(P<0.001)。在冷冻和石蜡标本中,PLA2R1表达与患者性别、年龄及临床分期无关,与病理类型相关。在冷冻和石蜡标本中,PLA2R1阳性均集中于特发性膜性肾病(72.0%和79.8%),但非特发性膜性肾病中,则分别为3.0%和19.4%。结论肾活检冷冻及石蜡标本中PLA2R1表达均与特发性膜性肾病相关,但冷冻标本在特发性膜性肾病诊断中更有价值。  相似文献   
76.
目的 探讨纳米细菌(NB)在前列腺结石形成中的作用,观察抗NB治疗前列腺结石是否有效。方法 本组50例,从2例手术治疗取出的前列腺结石中分离、培养、鉴定NB,建立NB致大鼠前列腺结石模型,并对28例保守治疗的前列腺结石患者行抗NB治疗。结果 从前列腺结石中分离出NB,并成功建立NB致大鼠前列腺结石模型。前列腺结石患者行抗NB治疗后,彩超显示结石直径逐渐缩小,慢性骨盆疼痛综合征(CPPS)症状显著改善。结论 NB与前列腺结石形成有关,抗NB治疗前列腺结石有效。  相似文献   
77.
目的探讨直接免疫荧光(direct immunofluorescence,DIF)检查在口腔黏膜大疱类疾病诊断中的价值。方法回顾性分析2009年5月至2014年3月中国医科大学口腔医学院确诊的73例口腔黏膜大疱类疾病患者的DIF检查结果,总结各类型口腔黏膜大疱类疾病的DIF表现特点,并与组织病理检查对该类疾病诊断的敏感性进行比较。结果 (1)各类型口腔黏膜大疱类疾病的DIF表现各具特征性,其中天疱疮可见表皮细胞间Ig G和(或)C3呈弥漫网状沉积,偶有Ig M、Ig A及纤维蛋白原沉积;类天疱疮可见基底膜带C3和(或)Ig G呈线状沉积,少有Ig M、Ig A及纤维蛋白原沉积。(2)DIF检查诊断口腔黏膜大疱类疾病的敏感性为76.7%,与组织病理检查敏感性(75.3%)相比,差异无统计学意义(χ^2=0.038,P〉0.05)。结论 DIF检查是诊断口腔黏膜大疱类疾病的重要手段,特别是当临床与组织病理诊断困难时,DIF技术极有价值。  相似文献   
78.
目的分析2004~2005年冬春季呼吸道合胞病毒(RSV)流行季节的亚型分布情况。方法采用直接免疫荧光法检测2004年10月~2005年4月间因急性下呼吸道感染住院儿童1040例鼻咽部分泌物中的常见病毒病原,随机选择RSV阳性标本174例,采用间接免疫荧光检测RSVA、B亚型,分析检测结果。结果1040例中,RSV阳性497例(47.8%),其中174例标本中,检测出RSVA亚型23例(13.2%),B亚型105型(60.4%),A、B亚型混合感染36例(20.7%),无法确定亚型的10例(5.7%)。检测期间各月份间、不同的年龄组间和临床诊断间的RSV亚型分布差异均无显著性意义(P>0.05),都以B亚型为主。结论2004~2005年冬春季RSV仍是儿童急性下呼吸道感染的主要病原,以B亚型为主;并有两种亚型同时感染的情况。  相似文献   
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80.
Sporadic inclusion body myositis (sIBM) contains non-necrotic myofibers that are surrounded and/or invaded by inflammatory cells. In this study we aimed to identify selective molecules that are present at this site. Myofibers of four biopsies of sIBM that were surrounded and/or invaded by inflammatory cells were microdissected, pooled and profiled by proteomic studies using mass spectrometry. Normal skeletal muscle tissue served as control. Based on the table of proteins that were detected in sIBM only, we selected nine extracellular matrix molecules and validated the results performing immunofluorescence. Seven out of nine proteins that were detected in sIBM by mass spectrometry showed different immunohistochemical results in myositis and normal controls. Of these, the small leucine-rich repeat proteins proline arginine-rich end leucine-rich repeat protein (PRELP) and biglycan were deposited precisely at myofibers surrounded and/or invaded by inflammatory cells both in sIBM and polymyositis. The basement membrane (BM) molecules merosin, perlecan, nidogen-2 and collagen IV were variably destroyed or increased at these sites. P component, which ensheathed all myofibers in normal controls, was absent from invaded myofibers. Similar to BM remodeling, the specific deposition of PRELP and biglycan may represent a mechanism to defend against immune attack. Loss of P component may affect the anchorage of the myofiber in the endomysium.  相似文献   
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