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21.
Expression of luminal and basal cytokeratins in human breast carcinoma 总被引:32,自引:0,他引:32
Abd El-Rehim DM Pinder SE Paish CE Bell J Blamey RW Robertson JF Nicholson RI Ellis IO 《The Journal of pathology》2004,203(2):661-671
We have examined basal and luminal cell cytokeratin expression in 1944 cases of invasive breast carcinoma, using tissue microarray (TMA) technology, to determine the frequency of expression of each cytokeratin subtype, their relationships and prognostic relevance, if any. Expression was determined by immunocytochemistry staining using antibodies to the luminal cytokeratins (CKs) 7/8, 18 and 19 and the basal markers CK 5/6 and CK 14. Additionally, assessment of alpha-smooth muscle actin (SMA) and oestrogen receptor status (ER) was performed. The vast majority of the cases showed positivity for CK 7/8, 18 and 19 indicating a differentiated glandular phenotype, a finding associated with good prognosis, ER positivity and older patient age. In contrast, basal marker expression was significantly related to poor prognosis, ER negativity and younger patient age. Multivariate analysis showed that CK 5/6 was an independent indicator for relapse free interval. We were able to subgroup the cases into four distinct phenotype categories (pure luminal, mixed luminal/basal, pure basal and null), which had significant differences in relation to the biological features and the clinical course of the disease. Tumours classified as expressing a basal phenotype (the combined luminal plus basal and the pure basal) were in a poor prognostic subgroup, typically ER negative in most cases. These findings provide further evidence that breast cancer has distinct differentiation subclasses that have both biological and clinical relevance. 相似文献
22.
The triple A or Allgrove syndrome is an autosomal-recessive disease (MIM*231550) characterized by the triad of achalasia, alacrima and adrenocorticotropic hormone (ACTH)-resistant adrenal insufficiency. Associated features of the syndrome are neurological and dermatological abnormalities. Until the discovery of the AAAS gene as the responsible gene in triple A syndrome, the diagnosis was based on characteristic clinical features. Here we present the clinical and molecular genetic data which demonstrated the marked phenotypic variability in three unrelated patients with triple A syndrome. The final diagnosis of triple A syndrome was confirmed by molecular analysis. In one patient with isolated achalasia, the diagnosis of triple A syndrome could only be made on the basis of the molecular genetic analysis of the AAAS gene. We therefore suggest that the diagnosis of triple A syndrome should be considered in patients who exhibit only one or two of the main symptoms (i.e. alacrima, achalasia or adrenal insufficiency). These patients require careful neurological investigation, and mutation analysis of the AAAS gene should be performed. 相似文献
23.
背景:小胶质细胞极化参与脊髓损伤后的炎症反应,并在其中发挥关键作用。相关研究表明,有效诱导小胶质细胞从M1促炎表型向M2抗炎表型极化,可以减轻脊髓损伤后的炎症反应,促进组织的修复再生和神经功能的恢复。目的:文章对小胶质细胞的功能和极化、小胶质细胞极化对脊髓损伤的影响及其潜在调控策略以及脊髓损伤后炎症反应进行综述。方法:检索PubMed、Web of Science和中国知网数据库,英文检索词为“microglia,polarization,spinal cord injury,inflammation”,中文检索词为“小胶质细胞、极化、脊髓损伤、炎症”,按纳入和排除标准共纳入80篇文献进行总结。结果与结论:①由小胶质细胞介导的稳定而持续的炎症反应,对脊髓损伤的预后至关重要。②在生理条件下,小胶质细胞处于M0静止表型,但在脊髓损伤后,小胶质细胞活化,进而极化成M1促炎表型,导致神经组织修复能力降低和出现持续性神经炎症。③在脊髓损伤的炎症反应过程中,调控小胶质细胞向M2表型极化或至少向M2表型倾斜,有利于抑制氧化应激反应、调节突触重塑、促进轴突再生和血管生成,是一种有效的调控策略。④截止到目前的研究表明,间充质干细胞、外泌体、临床药物、天然产物、miRNAs和靶点分子可调控小胶质细胞在M1和M2表型之间的转换,这为脊髓损伤后神经组织的修复提供了一种新的思路,未来需进一步研究小胶质细胞在脊髓损伤过程中调控极化的详细机制。 相似文献
24.
目的:探究巨噬细胞肿瘤疫苗的细胞形态与表型特征,并观察其CTL反应的诱导效果。方法:分别采用透射与扫描电子显微镜、免疫荧光染色及流式细胞术等技术对巨噬细胞肿瘤疫苗的超微结构及CD14、CD68、CD80、CD86、MHCⅡ等分子进行测定。采用生长状态良好的H22肿瘤细胞移植于接种不同肿瘤疫苗的实验小鼠,分别采用直接测量法、MTT法及比色法测定瘤重量、瘤体积、肿瘤细胞杀伤率和培养上清液LDH活性。结果:巨噬细胞肿瘤疫苗细胞表面有许多的伪足皱褶、囊泡,胞浆内有大量大小不一、形态不规则的吞噬体;CD14、CD68、CD80、CD86及MHCⅡ的阳性细胞率分别为53.90%、98.60%、26.50%、90.20%和25.40%。小鼠体内实验结果显示,巨噬细胞肿瘤疫苗接种组的肿瘤形成率、瘤体积与瘤重量明显低于对照组和石蜡诱生的巨噬细胞接种组(P均〈0.05);巨噬细胞肿瘤疫苗接种组的成瘤率与灭活肿瘤细胞接种组无明显差异(P〉0.05),但瘤体积与瘤重量明显低于灭活肿瘤细胞接种组(P均〈0.05)。另外,巨噬细胞肿瘤疫苗接种组的淋巴细胞自体肿瘤细胞杀伤率和培养上清液LDH活性分别高于对照组、灭活肿瘤细胞接种组和石蜡诱生的巨噬细胞接种组。结论:巨噬细胞肿瘤疫苗具备巨噬细胞的典型特征,该种细胞接种后可诱导机体产生特异性抗肿瘤免疫反应。 相似文献
25.
孤独症广泛表型的临床调查 总被引:5,自引:0,他引:5
目的:调查孤独症先证者家系中孤独症广泛表型(BAP)及其主要表现,统计其发生率,为进一步的神经心理和遗传研究建立基础.方法:使用家系调查表和Bolton孤独症广泛表型的操作定义手册,对75例孤独症先证者的家系进行筛查,对符合BAP定义的家属进行总结和分类.结果:75例先证者的家系亲属中共有42例符合BAP 的诊断,他们以社交缺陷表现为主,其次为语言发育障碍,以行为怪异为主要表现的最少.结论:BAP在孤独症家系中的存在对遗传学的研究可能提供一条有用的途径,有必要做进一步的研究和探讨. 相似文献
26.
Gallou C Chauveau D Richard S Joly D Giraud S Olschwang S Martin N Saquet C Chrétien Y Méjean A Correas JM Benoît G Colombeau P Grünfeld JP Junien C Béroud C 《Human mutation》2004,24(3):215-224
von Hippel-Lindau (VHL) disease arises from mutations in the VHL gene and predisposes patients to develop a variety of tumors in different organs. In the kidney, single or multiple cysts and renal cell carcinomas (RCC) may occur. Both inter- and intrafamilial heterogeneity in clinical expression are well recognized. To identify VHL-dependent genetic factors, we investigated the renal phenotype in 274 individuals from 126 unrelated VHL families in whom 92 different VHL mutations were characterized. The incidence of renal involvement was increased in families with mutations leading to truncated protein (MLTP) or large rearrangement, as compared to families with missense changes (81 vs. 63%, respectively; P=0.03). In the latter group, we identified two mutation cluster regions (MCRs) associated with a high risk of harboring renal lesions: MCR-1 (codons 74-90) and MCR-2 (codons 130-136). In addition, the incidence of RCC was higher in families with MLTP than in families with missense changes (75 vs. 57%; P=0.04). Furthermore, mutations within MCR-1 but not MCR-2 conferred genetic susceptibility to develop RCC. Overall, our data argued for a substantial contribution of the genetic change in the VHL gene to susceptibility to renal phenotype in VHL patients. 相似文献
27.
Anete M. Francisco‐Bagnariolli Spencer L.M. Payão Rosa S. Kawasaki‐Oyama Daher Sabbag Filho Rosimeire Segato Roger W. de Labio Maria de Lourdes L.F. Chauffaille Jean H. Priest 《American journal of medical genetics. Part A》2001,103(4):302-307
We report on a familial t(4;7)(q28;p22) with 2:2 adjacent‐1 unbalanced segregation producing duplication of 4q28→qter in multiple offspring. Within the large four‐generation pedigree, a carrier had a reproductive outcome that was approximately equal for 1) the balanced translocation, 2) normal chromosomes, and 3) viable 4q trisomy or pregnancy loss. The three individuals with chromosomal confirmation of trisomy 4q28→qter (comprising approximately 1.8% of the haploid autosomal length) had similar mental and developmental retardation, hypotonia, restricted speech, seizures, and facial anomalies but no cardiac, renal, or skeletal anomalies. It is suggested that these latter severe malformations, associated with the classic 4q2 to 3 group of anomalies, were from an imbalance outside 4q28→qter and were not necessarily related to the relatively large size of the trisomic segment. Multiple different chromosomes are reported to be rearranged with 4q in the production of distal 4q trisomy. The incidence of 4q rearrangement remains unexplained, but once it is present in a family, viability of a large trisomy in 4q seems to explain the number of affected individuals reported. © 2001 Wiley‐Liss, Inc. 相似文献
28.
We studied four sibs, two males and two females, who presented psychomotor retardation, typical flat facies and some features of the Marfan phenotype such as tall stature, long and slim limbs, arm span larger than height, "arachnodactyloid" hands and feet, little subcutaneous fat and muscle hypotonia. It is concluded that the aggregate of morphoneurological anomalies constitute a new syndrome probably inherited in an autosomal recessive fashion. 相似文献
29.
Nahid Tayebi David Q. Andrews Joseph K. Park Eduard Orvisky John McReynolds Donna M. Krasnewich 《American journal of medical genetics. Part A》2002,108(3):241-246
Congenital disorders of glycosylation (CDG) are a group of metabolic disorders with multisystemic involvement characterized by abnormalities in the synthesis of N‐linked oligosaccharides. The most common form, CDG‐Ia, resulting from mutations in the gene encoding the enzyme phosphomannomutase (PMM2), manifests with severe abnormalities in psychomotor development, dysmorphic features and visceral involvement. While this disorder is panethnic, we present the first cases of CDG‐Ia identified in an African American family with two affected sisters. The proband had failure to thrive in infancy, hypotonia, ataxia, cerebellar hypoplasia and developmental delay. On examination, she also exhibited strabismus, inverted nipples and an atypical perineal fat distribution, all features characteristic of CDG‐Ia. Direct sequencing demonstrated that the patient had a unique genotype, T237M/c.565‐571 delAGAGAT insGTGGATTTCC. The novel deletion–insertion mutation, which was confirmed by subcloning and sequencing of each allele, introduces a stop codon 11 amino acids downstream from the site of the deletion. The presence of this deletion–insertion mutation at cDNA position 565 suggests that this site in the PMM2 gene may be a hotspot for chromosomal breakage. Published 2002 Wiley‐Liss, Inc. 相似文献
30.
The purpose of this work was to evaluate the efficiency of free-flow electrophoresis as a method for separating mouse lymphocyte subsets. The surface phenotype of the cells contained in the various fractions collected after electrophoresis of CBA/J lymph node cells was investigated by means of single- and 2-color flow cytofluorometry (FCF) analysis. In agreement with previous works, B cells (sIg+, Thy-1-) were found to segregate in the low mobility (LM) fractions and T cells (sIg-, Thy-1+) in the high-mobility (HM) fractions. While the mean fluorescence intensity of sIg staining did not significantly vary as a function of electrophoretic mobility (EPM) that of Thy-1 staining tended to decrease with increasing EPM. The distribution of Lyt-1+ cells was roughly parallel to that of Thy-1+ cells. However, 2-color FCF analysis suggested the existence, in addition to a major Thy-1+ Lyt-1+ subpopulation, of a minor subset of Thy-1- Lyt-1+ cells. Lyt-2+ cells made up a peak in the cathodic HM region where they were enriched by up to 3-fold, and a trail in the more anodic HM fractions. Two-color FCF analysis showed that all Lyt-2+ cells recovered in these various electrophoretic fractions expressed the Lyt-1 antigen. Taken together, these data demonstrate that free-flow electrophoresis provides a powerful tool for the delineation and substantial enrichment of phenotypically distinct mouse peripheral T cell subsets. 相似文献