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991.
Role of MyD88 in diminished tumor necrosis factor alpha production by newborn mononuclear cells in response to lipopolysaccharide 总被引:11,自引:0,他引:11 下载免费PDF全文
Yan SR Qing G Byers DM Stadnyk AW Al-Hertani W Bortolussi R 《Infection and immunity》2004,72(3):1223-1229
Human newborns are more susceptible than adults to infection by gram-negative bacteria. We hypothesized that this susceptibility may be associated with a decreased response by leukocytes to lipopolysaccharide (LPS). In this study, we compared LPS-induced secretion of tumor necrosis factor alpha (TNF-alpha) by mononuclear cells (MNC) from adult peripheral blood and newborn umbilical cord blood in vitro and attempted to determine the mechanisms involved in its regulation. At a high concentration of LPS (10 ng/ml) and in the presence of autologous plasma, MNC from adults and newborns secreted similar amounts of TNF-alpha. However, in the absence of plasma, MNC from newborns secreted significantly less TNF-alpha compared to MNC from adults. Moreover, at a low concentration of LPS (0.1 ng/ml) and in the presence of plasma, TNF-alpha secretion was significantly lower for newborn MNC compared to adult MNC. Adults and newborns had similar numbers of CD14 and Toll-like receptor 4 (TLR-4)-positive cells as measured by flow cytometry. However, the intensity of the CD14 marker was greater for adult than for newborn cells. Incubation of cells with LPS led to an increase in CD14 and TLR-4 intensity for adult cells but not for newborn cells. The effect of LPS stimulation of adult or newborn cells was similar for ERK, p38, and IkappaBalpha phosphorylation, as well as IkappaBalpha degradation. Finally, we assessed levels of the TLR-4 adapter protein, the myeloid differentiation antigen 88 (MyD88). We found a direct relation between adult and newborn TNF-alpha secretion and MyD88, which was significantly decreased in newborn monocytes. Since TLR-4 signals intracellularly through the adapter protein, MyD88, we hypothesize that MyD88-dependent factors are responsible for delayed and decreased TNF-alpha secretion in newborn monocytes. 相似文献
992.
Gene amplifications have been observed in many different tumor cells, and many of these changes are related to tumor pathogenesis. Comparative genomic hybridization (CGH) using metaphase chromosomes can detect changes in chromosome copy number with a resolution of 10-20 Mb. Current advances in CGH analysis in a microarray format allow us to refine such changes down to the gene level. We applied microarray technology to detect novel gene amplification in a malignant mixed tumor of salivary gland. Besides detecting previously known gene amplifications (MDM2 and MYC), we identified four other highly amplified genes located at 8q11.2 approximately q13: MGC2177, PLAG1, PSMC6P, and LYN. The amplification was further validated with real-time quantitative polymerase chain reaction. 相似文献
993.
Diversity of rotavirus strains among children with acute diarrhea in China: 1998-2000 surveillance study 总被引:24,自引:0,他引:24 下载免费PDF全文
Fang ZY Yang H Qi J Zhang J Sun LW Tang JY Ma L Du ZQ He AH Xie JP Lu YY Ji ZZ Zhu BQ Wu HY Lin SE Xie HP Griffin DD Ivanoff B Glass RI Gentsch JR 《Journal of clinical microbiology》2002,40(5):1875-1878
As part of a national rotavirus surveillance activity, we collected fecal specimens from 3,177 children with acute diarrhea in 10 regions of China between April 1998 and April 2000 and screened them for rotavirus. Rotavirus was detected in 41% (n = 1,305) of specimens, and in these, G1 was the predominant serotype (72.6%), followed by G3 (14.2%), G2 (12.1%), G4 (2.5%), G9 (0.9%), and G untypeable (0.7%). Among 327 G-typed strains tested for P genotype, 14 different P-G combinations were identified, with the globally common strains P[8]G1, P[4]G2, P[8]G3, and P[8]G4 representing 75.6% of all typed rotavirus strains. Among the uncommon strains, 11 were P[6]G9, and others included P[6]G1, P[6]G3, and five novel P-G combinations (P[9]G1, P[4]G1, P[4]G3, P[4]G4, and P[8]G2). Our results indicate that while the common rotavirus strains remain predominant, the diversity of strains is much greater than was previously recognized. 相似文献
994.
人巨细胞病毒UL136基因在临床低传代分离株中多态性分析 总被引:3,自引:1,他引:3
目的 研究人巨细胞病毒(human cytomegalovirus,HCMV)UL136基因在临床低传代分离株中的多态性,探讨其多态性与HCMV先天性感染不同致病性之间的关系。方法 对48株经荧光定量PCR方法检测HCMV DNA为阳性的临床低传代分离株进行HCMV ULl36全序列PCR扩增,对于扩增阳性的12株PCR产物进行ULl36基因全序列测定及结果分析。结果 48株临床低传代分离株ULl36 PCR扩增,12株阳性,阳性率25%,以HCMV Toledo株作为参考株,进行序列比较分析表明,12株临床分离株ULl36开放阅读框架(open reading frame,ORF)长度均与Toledo株相同,为723bp,编码241个氨基酸的蛋白。DNA序列变异均为碱基替换,不同临床分离株ULl36基因与Toledo株进行同源性比较,结果在核苷酸水平为97.7%~99.3%,氨基酸水平为96.6%~99.1%。ULl36编码蛋白的氨基酸变异率为0.83%~3.3%。二级结构预测分为两种构象。大多数HCMV ULl36蛋白翻译后修饰位点在所有分离株中均高度保守,仅几个位点在一些分离株中存在缺失或新增。Toledo株及12株临床分离株核苷酸及氨基酸序列系统进化树分析表明:45J最接近Toledo株。结论 12株临床低传代分离株HCMV ULl36基因DNA及其编码产物的氨基酸序列比较保守,但仍存在一定多态性。未发现不同临床分离株ULl36基因多态性与HCMV先天性感染的表现关系。 相似文献
995.
Gil LH Alves FP Zieler H Salcedo JM Durlacher RR Cunha RP Tada MS Camargo LM Camargo EP Pereira-da-Silva LH 《Journal of medical entomology》2003,40(5):636-641
Studies on seasonal anopheline fauna variation were performed in two distinct settlements in the State of Rond?nia, Brazil: one at the Madeira River banks (Portuchuelo) with stable native Amazonian population; the other at an inland lumber-extracting farm (Urupá) in dry land, in which adults are mostly migrants. During a 6-yr period (1994-2000), 8,638 adult anophelines were collected: 2,684 in Urupá and 5,954 in Portuchuelo. Anopheles darlingi represented >95% of total mosquitoes caught. Dissection of 4,424 A. darlingi females yielded a very low sporozoite infection index below 0.1%. Oocysts were found in both localities in approximately 0.1% of dissected mosquitoes. Determination of the hour biting rates disclosed seasonal variations in both localities. However, in Portuchuelo, mosquito density peaked at the acme of the rainy season, whereas at Urupá it peaked in the dry season. The increase in mosquito density and incidence of malaria cases were coincident. The high mosquito densities observed in the riverine settlement of Portochuelo sector B, which permits evaluation in > 10,000 mosquitoes' bites/person/year, could explain, in spite of the low mosquito's infection index, the previously described development of natural immunity in the local population that is not observed in the dry land agroindustrial settlement of Urupá. 相似文献
996.
尖锐湿疣患者治疗前后血清IL-2、IL-6、TNF-α和外周血B细胞、T淋巴细胞亚群检测的临床意义 总被引:1,自引:0,他引:1
目的:探讨了尖锐湿疣患者治疗前后血清IL-2、IL-6、TNF-α和外周血B细胞、T淋巴细胞亚群水平及临床意义.方法:分别应用放免法、酶联法和单克隆抗体法对42例尖锐湿疣患者进行了血清IL-2、IL-6、TNF-α和外周血B细胞、T淋巴细胞亚群水平测定,并与30名正常健康人作比较.结果:尖锐湿疣患者在治疗前血清TNF-α水平和B细胞数均非常显著地高于正常人组(P<0.01),而IL-2、IL-6、CD3、CD4、CD4/CD8比值则显著地低于正常人组(P<0.01),经治疗后6个月,与正常人比较仍有显著性差异(P<0.05).结论:尖锐湿疣是一种自身免疫调节失常的性传播疾病. 相似文献
997.
Ho Chang Kuo Chih Lu Wang Chi Di Liang Hong Ren Yu Hsin Hsu Chen Lin Wang Kuender D Yang 《Journal of microbiology, immunology, and infection》2007,40(5):395-400
BACKGROUND AND PURPOSE: This study was conducted to investigate whether changes in the complete blood count (CBC)/differential count (DC) and C-reactive protein (CRP) were correlated to Kawasaki disease (KD) with coronary artery lesions (CALs). METHODS: A retrospective analysis was performed of all children with KD at Chang Gung Memorial Hospital at Kaohsiung from 2001 to 2006. KD patients were divided into those with and without CALs for testing of correlations with changes in CBC/DC and CRP levels. RESULTS: A total of 147 patients were enrolled for this analysis. Serial CBC/DC and CRP measurements and echocardiographic data for determination of CAL formation were obtained before and after intravenous immunoglobulin (IVIG) treatment. There were 44 (29%) KD patients having CAL formation (>3 mm in diameter of internal lumen). There was no significant difference in terms of age distribution and major diagnostic criteria between KD patients with and without CALs. Male KD patients, however, had a significantly higher rate of CAL formation (p=0.009). In multivariate logistical regression analysis, persistent monocytosis after IVIG treatment was the only factor significantly correlated to CAL formation (p=0.003). CONCLUSIONS: Of the febrile routine measurements of CBC/DC and CRP in KD, persistent monocytosis after IVIG treatment was correlated to CAL formation. Further studies to clarify the mechanism of monocytosis may help prevent the CALs of KD. 相似文献
998.
复杂手术常需多科医生协商制定综合性治疗方案,网络协同三维可视化软件可使方案制定直观而精确。我们采用VTK工具包对DICOM格式CT图像数据进行三维重建并作网格简化,将结果所得多边形网格模型无缝集成到用HOOPS/3DAF所开发的图形系统进行显示,并用HOOPS/Stream工具包转成适合网络传输的HSF无损压缩流文件,再用HOOPS/NET工具包实现基于Client/Server架构的协同三维交互可视化系统。所得三维重建结果清晰,协同三维可视化操作实时度高。本研究实现了一个协同手术仿真开发平台,该架构易于进一步添加模拟手术操作与修复体设计功能。 相似文献
999.
采用墨汁硝酸银水溶液局部动脉灌注方法,研究了胎儿、犬和家兔肾上腺(总计80例)器官内的淋巴管.所见结果表明:胎儿和犬肾上腺被膜内及腺体内的较粗大静脉周围存在淋巴管和毛细淋巴管;家兔肾上腺的淋巴管仅分布于被膜内;在肾上腺皮质和髓质的实质内,无论胎儿、犬和兔,仅有血管并无淋巴管或毛细淋巴管. 相似文献
1000.
Responses of macrophages in rat dorsal root ganglia following peripheral nerve injury 总被引:3,自引:0,他引:3
Summary Immunohistochemical studies with monoclonal antibodies to macrophage antigens were performed on sections of rat lumbar dorsal root ganglia. In confirmation of previous observations, cells with macrophage antigenicity were detected in normal ganglia. Many of these presumptive macrophages were perineuronal in contact with the neuron/satellite cell complex, a few were perivascular, and others were in interstitial position not in apparent contact with either blood vessels or neurons. The number of macrophages in lumbar dorsal root ganglia started to increase 2–4 days after sciatic nerve transection and remained elevated for four weeks. Perineuronal macrophages resembled satellite glial cells in light microscope appearance but were distinguished from glial cells by their lack of S-100 immunoreactivity. Following this sciatic nerve injury, macrophage counts were modestly increased in contralateral lumbar dorsal root ganglia but not in cervical dorsal root ganglia. Thus peripheral nerve injury induces a recruitment and/or proliferation of macrophages in the corresponding dorsal root ganglion. Although the functions of these macrophages are unclear, those in perineuronal position could contribute to the survival or regeneration of axotomized neurons. 相似文献