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971.
人类白细胞抗原-G突变体cDNA克隆及在K562细胞上的表达 总被引:2,自引:0,他引:2
目的:克隆人类白细胞抗原-G(Human leukocyte antligen-G,HLA-G)突变体cDNA,并使其在HLA-I类阴性的K562细胞上获得稳定表达,为研究配-受体之间的识别机制奠定基础。方法:用RT-PCR方法从人子宫蜕膜组织扩增出HLA-GcDNA,得到全长HLA-GPCR产物后,用桥式PCR方法进行定点点突变,将突变的目的基因亚克隆于逆转录,将突变的目的基因亚克隆于逆转录mG-pLNCX表达载体,采用感染的方法将重组质粒转入K562细胞,最后经G418筛选及有限稀释,利用单克隆抗体W6/32进行FACS及mRNA检测,观察HLA-G突变体在靶细胞表面的表达。结果:HLA-G突变体分子在经mG-pLNCX转染的靶细胞表面获得稳定高表达。结论:成功构建了mG-pLNCX表达载体,并使HLA-G突变体分子在HLA-I类阴性的靶细胞K562细胞上获得稳定表达。 相似文献
972.
肾混合性上皮间质肿瘤和成人囊性肾瘤的临床病理学观察 总被引:1,自引:0,他引:1
Objective To study the clinicopathologie features,immunophenotype and differential diagnosis of mixed epithelial and stromal tumor of kidney ( MEST) and adult cystic nephroma ( CN).Methods Five cases of MEST and 4 cases of CN were retrospectively analyzed.Immunohistochemical study was carried out and the literature was reviewed.Results All of the five patients with MEST were females.Their median age was 45 years.For CN,there were 3 males and 1 female and their median age was 41 years.All patients presented with loin pain and hematuria.On gross examination,MEST was well-circumscribed but non-encapsulated.There was no evidence of haemorrhage or necrosis.Three of the cases were solid in nature.One was composed of a mixture of solid and cystic elements,while the remaining case showed a multicystic cut surface bridged by thick fibrous septa.On the other hand,CN were well-circumscribed and encapsulated.They were multiloculated cystic in nature.The cystic spaces were separated by thin septa and there was no significant solid or necrotic component.Histologically,MEST consisted of proliferation of cystically dilated glands admixed with spindly stromal cells with various cellularity and growth patterns.Both the glandular and stromal elements were well-differentiated with no cytologic atypia identified.The glandular structures in 2 of the cases were partially lined by endometrial or tubal epithelium.In contrast,the thin-walled cystic spaces in CN were lined by a single layer of epithelium.Immunohistochemical study showed that the epithelial cells were positive for pan-cytokeratin and epithelial membrane antigen.The spindle cells in MEST expressed vimentin (5/5 ) ,smooth muscle actin (3/5 ),desmin (4/5 ),CD10 (5/5),estrogen receptor (4/5) and progesterone receptor (4/5).They were negative for HMB45,CD34,CD117 and S-100 protein.On the other hand,the spindle cells in CN were variably positive for vimentin (4/4),smooth muscle actin (4/4),desmin (1/4),estrogen receptor (3/4) and progesterone receptor (1/4).They were negative for CD10,HMB45,CD34,CD117 and S-100 protein.Conclusions Both MEST and CN are uncommon renal neoplasm.Most of them run a benign clinical course.The stromal cells in MEST show smooth muscle or myofibroblastic differentiation.Areas demonstrating Miillerian features also existed in some cases.MEST and CN share overlapping histological and immunohistochemical features,and may represent spectrum of the same group of lesions. 相似文献
973.
Parkin localizes to the Lewy bodies of Parkinson disease and dementia with Lewy bodies 总被引:31,自引:0,他引:31
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Schlossmacher MG Frosch MP Gai WP Medina M Sharma N Forno L Ochiishi T Shimura H Sharon R Hattori N Langston JW Mizuno Y Hyman BT Selkoe DJ Kosik KS 《The American journal of pathology》2002,160(5):1655-1667
Mutations in alpha-synuclein (alpha S) and parkin cause heritable forms of Parkinson disease (PD). We hypothesized that neuronal parkin, a known E3 ubiquitin ligase, facilitates the formation of Lewy bodies (LBs), a pathological hallmark of PD. Here, we report that affinity-purified parkin antibodies labeled classical LBs in substantia nigra sections from four related human disorders: sporadic PD, inherited alphaS-linked PD, dementia with LBs (DLB), and LB-positive, parkin-linked PD. Anti-parkin antibodies also detected LBs in entorhinal and cingulate cortices from DLB brain and alphaS inclusions in sympathetic gangliocytes from sporadic PD. Double labeling with confocal microscopy of DLB midbrain sections revealed that approximately 90% of anti-alpha S-reactive LBs were also detected by a parkin antibody to amino acids 342 to 353. Accordingly, parkin proteins, including the 53-kd mature isoform, were present in affinity-isolated LBs from DLB cortex. Fluorescence resonance energy transfer and immunoelectron microscopy showed that alphaS and parkin co-localized within brainstem and cortical LBs. Biochemically, parkin appeared most enriched in cytosolic and postsynaptic fractions of adult rat brain, but also in purified, alpha S-rich presynaptic elements that additionally contained parkin's E2-binding partner, UbcH7. We conclude that parkin and UbcH7 are present with alphaS in subcellular compartments of normal brain and that parkin frequently co-localizes with alpha S aggregates in the characteristic LB inclusions of PD and DLB. These results suggest that functional parkin proteins may be required during LB formation. 相似文献
974.
目的了解Ⅲ型胶原肾小球病的形态学改变,并对Ⅲ型胶原可能的细胞来源进行初步探讨。方法对3例肾活检组织进行光镜、免疫荧光、电镜和Ⅰ、Ⅲ、Ⅳ型胶原及d平滑肌肌动蛋白(α-SMA)的免疫组织化学染色(SP法)观察。结果2例患者临床表现为肾病综合征,其中1例伴高血压,第3例表现为肾功能不全和肾性高血压。3例均无肾病家族史。光镜检查可见肾小球基膜内和系膜区弥漫性过碘酸-希夫反应阳性物质沉积,系膜细胞无明显增生。电镜检查在基膜内疏松层和系膜区可见大量胶原纤维沉积,系膜细胞胞膜下平行排列的束状微丝明显增加。免疫组织化学显示这些胶原纤维为Ⅲ型胶原,Ⅰ型和Ⅳ型胶原阴性,同时系膜区多数系膜细胞α-SMA阳性。结论Ⅲ型胶原肾小球病光镜、电镜及免疫组织化学上都有其特殊的病理改变。肾小球内激活的系膜细胞可能是Ⅲ型胶原的来源。 相似文献
975.
Reibman J Hsu Y Chen LC Kumar A Su WC Choy W Talbot A Gordon T 《American journal of respiratory cell and molecular biology》2002,27(4):455-462
Environmental pollutants, including ambient particulate matter (PM), increase respiratory morbidity. Studies of model PM particles, including residual oil fly ash and freshly generated diesel exhaust particles, have demonstrated that PM affects inflammatory airway responses. Neither of these particles completely represents ambient PM, and therefore questions remain about ambient particulates. We hypothesized that ambient PM of different size fractions collected from an urban environment (New York City air), would activate primary culture human bronchial epithelial cells (HBECs). Because of the importance of granulocyte-macrophage colony-stimulating factor (GM-CSF) on inflammatory and immunomodulatory processes, we focused our studies on this cytokine. We demonstrated that the smallest size fraction (ultrafine/fine; < 0.18 micro m) of ambient PM (11 micro g/cm(2)), upregulated GM-CSF production (2-fold increase). The absence of effect of carbon particles of similar size, and the day-to-day variation in response, suggested that the chemical composition, but not the particle itself, was necessary for GM-CSF induction. Activation of the extracellular signal-regulated kinase and the p38 mitogen-activated protein kinase was associated with, and necessary for, GM-CSF release. These studies serve to corroborate and extend those on model particles. Moreover, they emphasize the role of the smallest size ambient particles in airway epithelial cell responses. 相似文献
976.
977.
Heterogeneity of hepatitis delta antigen 总被引:10,自引:0,他引:10
Hepatitis delta antigen (HDAg) is the only known protein encoded by the hepatitis delta virus (HDV). Two HDAg species of different sizes have been detected in the sera and livers of the infected humans, chimpanzees, and woodchucks, even though only one RNA species was previously identified in most of the HDV strains. To study HDAg heterogeneity, we took advantage of the fact that a single base mutation at nucleotide 1015 (C to U), which results in an amber termination codon in the HDAg open reading frame (ORF), eliminates a unique Ncol restriction enzyme site. We screened various HDV cDNA clones and detected sequence heterogeneity of the HDAg-coding region on the basis of the presence or absence of the Ncol site. Five delta hepatitis patients were examined. In every patient, two types of HDAg-coding sequence were detected at nucleotide 1015: one which contains a C and results in an ORF encoding a delta antigen of 214 amino acids, and the other which possesses a U and results in an amber termination codon and a truncated HDAg species of 195 amino acids. The in vitro translation products of these two ORFs comigrated with the two HDAg species from the patient's plasma on SDS polyacrylamide gels. Polymerase chain reaction (PCR) amplification of the HDV RNA from some patients' sera and subsequent sequencing showed several additional mutations in the HDAg-coding region. These mutations are independent of the C or U nucleotide change at the site of the amber termination codon.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
978.
Hongying Zhang Hong Bu Huijiao Chen Bing Wei Weiping Liu Jia Guo Fengyuan Li Dianying Liao Yuan Tang Zhang Zhang 《Applied immunohistochemistry & molecular morphology》2008,16(1):32-39
Most adrenocortical tumors (ACTs) can be diagnosed directly by a combination of morphologic features and clinical findings. However, sometimes it may be difficult to distinguish ACTs from other neoplasms such as pheochromocytomas and some metastatic tumors, particularly for small biopsy specimens because they may be morphologically similar. Expression of calretinin has recently been suggested as a valuable immunomarker for the differential diagnosis between ACTs and other tumors; however, its diagnostic value is still under debate. To determine the diagnostic value of calretinin in Chinese patients with adrenocortical and non-ACTs, we employed both polyclonal and monoclonal anticalretinin to characterize the expression of calretinin in adrenal tissues and compared its expression with that of inhibin alpha, Melan-A, cytokeratin, or CD99 by immunohistochemistry in tissue microarrays and standard tissue sections of 414 specimens. Our results revealed that calretinin was expressed by adrenocortical cells, but not by the other cells tested and the percentage of calretinin-positive ACTs reached 99% when stained with polyclonal antibodies, which was higher than that with monoclonal anticalretinin (91.3%), anti-Melan-A (90.3%), antiinhibin alpha (81.6%). In addition, our results also revealed that ACTs were stained by cytokeratin (AE1/AE3) with variable degrees (58.7%). Furthermore, unlike anti-Melan-A that stained all metastatic malignant melanoma, anticalretinin did not recognize other tested tumors. Therefore, immunohistologic staining with polyclonal anticalretinin is more sensitive than other antibodies tested for the diagnosis of ACTs. However, monoclonal anticalretinin appeared to be more specific. Importantly, our data suggested that the fried-egg-like staining pattern, but not the mere cytoplasmic staining, was characteristic of anticalretinin staining in adrenocortical tissues. Notably, a few anticalretinin negative-ACTs were stained by other immunomarkers that we tested. Thus, the combinational characterization of calretinin (either by polyclonal or monoclonal antibody), inhibin alpha, and Melan-A expression is of great significance in the differential diagnosis of ACTs. 相似文献
979.
目的: 研究通过幼兔长时间体-肺循环分流,建立高动力性肺动脉高压模型方法的可行性。 方法: 将1月龄幼兔正中开胸,行左颈总动脉与主肺动脉吻合,形成持续左向右分流。3个月后通过彩超证实吻合血管通畅性,并测定其肺动脉收缩压(PASP)、肺动脉舒张压(PADP)、平均压(MPAP),观测肺小动脉病理变化、管壁厚度指数(TI)、面积指数(AI)。 结果: 分流组3个月后,21只形成肺动脉高压。分流血管阻断前、后PASP、PADP、mPAP明显高于对照组(P<0.05)。肺组织病理检查示肺小动脉管壁增厚、管腔狭窄,与对照组比,TI和AI 明显增加(P<0.05)。 结论: 幼兔经体-肺循环分流手术3个月后,可形成与临床先心病病理生理相接近的高动力性肺动脉高压。该模型稳定、可靠、经济。 相似文献
980.
不同胎龄的胎儿和少儿皮肤中bax,bcl-2和p53基因表达的变化 总被引:1,自引:0,他引:1
目的:探讨凋亡相关基因bax, bcl-2和p53在不同胎龄的胎儿皮肤和少儿皮肤组织中表达的变化特征及其可能的生物学意义。方法: 运用末端脱氧核糖转移酶介导的生物素化脱氧尿嘧啶缺口标记技术(TUNEL)检测18例不同胎龄(13-32周)的胎儿皮肤和6例少儿皮肤组织中细胞凋亡的变化后,提取这些皮肤组织中的总RNA,分离mRNA,用RT-PCR方法检测bax, bcl-2和p53基因在不同组织中的表达变化特征。结果: 随着胎儿的生长发育,皮肤组织中的细胞凋亡率逐渐增加。在早期妊娠胎儿的皮肤中,bcl-2基因表达水平较高,随着胎龄的增加,bcl-2基因的转录本含量逐渐降低,在少儿的皮肤组织中,这种基因的表达量明显低于早期妊娠胎儿皮肤(P<0.01)。与bcl-2基因不同,在早期妊娠胎儿皮肤组织中,p53基因表达水平较低,而在晚期妊娠胎儿和少儿的皮肤内,该基因表达较强,而bax基因在不同发育时期的胎儿和少儿皮肤组织中表达差异不显著(P>0.05)。结论: 晚期妊娠胎儿和少儿皮肤组织中细胞增殖减缓,细胞趋向分化或凋亡的增加可能与p53基因表达增强,bcl-2表达降低相关;而p53表达降低,bcl-2表达升高可能是早期妊娠胎儿皮肤中细胞凋亡较少的机制之一。 相似文献