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1.
Immunization or reimmunization of A-negative pigs with red blood cells (RBC) from A-positive donors yielded anti-A antibodies reacting in high titres with phenotype A(Ac) RBC and, in some cases, in low dilutions, with phenotype Aw(Ap) RBC also. An attempt to raise the anti-A level by immunization with saliva which contained A substance was likewise successful. Repeated immunization of A-negative recipients with the RBC of A-positive donors (compatible in all other factors), with the aid of adjuvant, is recommended as the best way of obtaining Aw typing reagents.  相似文献   

2.
Background. The aim of this study was to assess the correlation between the prevalence of Helicobacter pylori strains possessing cytotoxin-associated gene A ( cag A) in children and the intensity of clinical complaints and morphological changes of the gastric mucosa.
Materials and Methods. A group of 80 children with gastrointestinal complaints was included in this study. Pathologists examined mucosal biopsy specimens from these patients. The urease test and multiplex polymerase chain reaction (MPCR) were used to identify H. pylori strains.
Results. In the group of children infected with cag A-positive H. pylori strains, fourth-degree gastritis was more frequent than in the group with cag A-negative H. pylori colonization. In histopathological assessment, infection with cag A-positive H. pylori was associated also with higher grades of inflammatory intensity and activity.
Conclusions. Marked inflammation of the antral mucosa was significantly more frequent in children infected with cag A-positive H. pylori than in those infected with cag A-negative H. pylori , as assessed endoscopically and histopathologically. No specific symptoms for cag A-positive and cag A-negative H. pylori infection were observed.  相似文献   

3.
本文采用RT-PCR的方法检测胃癌组织的REG 1A基因mRNA表达.并分析其与胃癌临床特征的相关性.结果显示有78%(183/235)的原发性胃癌REG ;A mRNA阳性.REG 1A mRNA在胃癌中的表达与肿瘤的浸润生长方式、印戒细胞癌及低分化胃腺癌关系密切.与REG lA mR.NA阳性的肿瘤患者相比,REG lA mRNA阴性高分化腺癌患者有更好的预后.同时REG 1A mR-NA阳性的肿瘤发生血行转移的机会要显著高于REG lA mRNA阴性肿瘤.因此REG lA mRNA的表达与胃癌浸润性生长密切相关,可能是高分化胃腺癌的一个不良预后指标.  相似文献   

4.
The aim of study was to determine a production of proteinA in coagulase-negative Staphylococcus aureus (CNSA) or CF-negative S. aureus (CFNSA) strains. 59 CNSA and 18 CFNSA strains were isolated between 1997 and 2003 from different clinical specimens. The Protein A production was determined by immunoblotting method. The presence of protein A gene (spa) was investigated using the polymerase chain reaction (PCR). Two sets of phages and RFLP (Restriction Fragment Lenth Polymorphism) of coa gene method were used for typing strains. The results proved that the lack of ability of protein A production occurs more frequently in protein A-negative CFNSA strains with compare to the CNSA, which are protein A-positive for the majority of strains. Deficiencies of protein A, doesn't seem to be caused by the loss of spa gene. Protein A-negative CFNSA strains have phagotypes, RFLP and antibiotic resistant patterns which differ them from protein A-negative CNSA strains. Almost all of protein A-negative CFNSA and CNSA strains are resistant to methicillin.  相似文献   

5.
Previous studies showed an association between latent adenoviral infection with expression of the adenoviral E1A gene and chronic obstructive pulmonary disease (COPD). The present study focuses on how the adenoviral E1A gene could alter expression of growth factors by human bronchial epithelial (HBE) cells. The data show that connective tissue growth factor (CTGF) and transforming growth factor (TGF)-beta 1 mRNA and protein expression were upregulated in E1A-positive HBE cells. Upregulation of CTGF in this in vitro model was independent of TGF-beta secreted into the growth medium. Comparison of E1A-positive with E1A-negative HBE cells showed that both expressed cytokeratin but only E1A-positive cells expressed the mesenchymal markers vimentin and alpha-smooth muscle actin. We conclude that latent infection of epithelial cells by adenovirus E1A could contribute to airway remodeling in COPD by the viral E1A gene, inducing TGF-beta 1 and CTGF expression and shifting cells to a more mesenchymal phenotype.  相似文献   

6.
Blood groups, including rhesus grouping, have been determined in 218 donors and HLA of loci A, B, C in 121 donors immunized with adsorbed tetanus toxoid (40 binding units). The presence of HLA Aw 32, B 8; HLA Bw 16, haplotypes A3 Bw 16 and A1, blank antigens of locus C is linked with the production of, respectively, high or low (less than or equal to 16 I.U./ml) antibody titers. The effectiveness of immunization is influenced by agglutinogen B, which is confirmed by its associations (in a complex with HLA Bw 16 or Bw 35) with low immune response.  相似文献   

7.
We examined the hypothesis that ambient particulate matter with a diameter of <10 microm (PM(10))-induced lung inflammation is amplified by latent adenovirus infection. Inflammatory mediator expression in response to PM(10) exposure was compared between adenovirus E1A-transfected A549 alveolar epithelial cells and cells transfected with control plasmid. Messenger RNA was measured by the RNase protection assay and protein by ELISA or immunocytochemistry. Intercellular adhesion molecule-1 and IL-8 mRNA and protein were increased in E1A-positive cells exposed to 500 microg/ml PM(10). Monocyte chemoattractant protein-1 mRNA and protein were unchanged in E1A-positive cells but increased in E1A-negative cells after 100 and 500 microg/ml PM(10) exposure. Electrophoretic mobility shift assays showed increased NF-kappaB and decreased specificity protein 1 nuclear binding in E1A-positive cells exposed to PM(10). These results indicate that E1A modulates cytokine and adhesion molecule expression in epithelial cells in a manner that could amplify PM(10)-induced lung inflammation. We suggest that this amplified inflammatory response may contribute to the pathogenesis of exacerbations of chronic obstructive pulmonary disease associated with exposure to particulate matter air pollution.  相似文献   

8.
In situ hybridization for trk A mRNA in trigeminal ganglion neurons retrogradely labeled with FluoroGold from the mandibular incisor demonstrated limited expression of the high-affinity nerve growth factor (NGF) receptor in this presumptive nociceptor population. Immunocytochemistry using polyclonal anti- trk A antibodies confirmed this result and extended it to show low levels of trk A protein expression in afferents labeled from the cornea. Less than 10% of the cells innervating the incisor, and ~15% of those innervating the cornea, were trk A-positive in adult and neonatal mice. This proportion is considerably lower than that observed in Dorsal Root Ganglion nociceptors, in which ~80% in neonates and ~40% in adults express trk A (Molliver and Snider, J Comp Neurol 381: 428-438, 1997). Presumptive trigeminal nociceptors were further identified on the basis of expression of Calcitonin gene related peptide. In the entire ganglion, ~43% of the trk A-positive cells were CGRP-positive, and ~44% of the CGRP-positive cells were trk A-positive. Most trk A-positive cells that were CGRP-negative were medium-to-large diameter, while most of those that were CGRP-positive but trk A-negative were small diameter. Only ~5% of trk A-positive cells labeled from the incisor, and ~10% from the cornea, were CGRP-positive. Approximately 15% of the corneal or pulpal afferent neurons expressed ret -immunoreactivity. These results suggest that trigeminal nociceptors differ from spinal nociceptors in several significant ways. Differences in neurotrophic requirements may be related to differences in target tissues, in embryonic origin of some trigeminal ganglion cells, or in the timing of down-regulation of trk A expression in trigeminal ganglion cells.  相似文献   

9.
目的:探讨腺病毒E1A蛋白对细胞内抗氧化物质谷胱甘肽(GSH)水平的影响及氧化应激对腺病毒E1A蛋白介导的核因子-κB(NF-κB)转录活化的影响。方法:构建稳定表达E1A蛋白的大鼠肺泡上皮细胞(E1A组)及对照质粒转染细胞(对照组),每组5×105个细胞,试验重复3次。采用H2O2刺激细胞,检测细胞内GSH水平。脂多糖(LPS)和肿瘤坏死因子-α(TNF-α)进行刺激,丁胱亚磺酰亚胺(BSO)进行干预,Western blot法检测NF-κB和AP-1蛋白的表达。结果:E1A+细胞内GSH基础水平与E1A-比较无显著差异,但在H2O2作用后没有诱导出GSH含量的上升,表现为下降而低平的趋势,去除氧化剂后,仍低于正常水平。E1A-细胞在氧化剂的作用后呈明显的上升趋势,去除氧化剂后仍高于基础水平。细胞内NF-κB蛋白表达(积分吸光度值):刺激前E1A+细胞分别为79.3±4.6和80.3±3.8,在LPS和TNF-α刺激后分别为81.8±3.9~89.9±1.6和94.1±1.9~99.8±1.6,均明显高于对照组(刺激前分别为68.3±3.8和69.4±4.3,刺激后分别为70.1±2.8~80.8±3.6和73.4±4.9~83.2±6.7)。给予BSO预处理后再用LPS和TNF-α刺激,E1A-细胞NF-κB蛋白表达的积分吸光度值(1.22±0.16和1.75±0.13)与LPS或TNF-α单独作用组(1.25±0.18和1.69±0.19)无明显差别;E1A+细胞NF-κB蛋白表达的积分吸光度值(1.75±0.10和2.26±0.21)明显高于LPS或TNF-α单独作用组(1.35±0.12和1.80±0.14)。结论:腺病毒潜伏感染持续表达E1A蛋白可以影响细胞GSH,降低细胞对氧化应激的耐受性,并可能通过此机制造成NF-κB异常转录活化,而GSH的降低又进一步放大了E1A介导的NF-κB转录活化作用。  相似文献   

10.
The analysis of more than 140 "weak A" samples: A3, Ax, Aend, Am, Ay and Ael, support the classical distinction between each subgroup which has been established on serological and genetical data. Accordingly, a valuable classification of these rare phenotypes must take into account, (i) the mode of inheritance, (ii) the agglutination pattern of the RBC by anti-A reagents, (iii) the presence or absence of soluble A substances in the saliva of secretors. The question is then open to know if such related erythrocytic antigens, whose specificity appears to be very similar, could be described on a quantitative basis or on qualitative structural variations. Evidence for quantitative differences was first demonstrated by a gradual decrease in the standard agglutinability of "weak A" RBC with human anti-A (B) sera, from A3 red cells (63 +/- 10%) to Ax (33 +/- 10%), Aend (10 +/- 5%) then Am, Ay and Ael (0%), and secondly by direct measurement of A antigen site densities, the mean values being respectively 35.10(3) A sites/RBC (A3); 4.8 10(3) (Ax); 3.5 10(3) (Aend) and 0.7 10(3) (Am, Ael). Further investigation on A3, Ax and Aend RBC agglutinability lead also to the demonstration of a large heterogeneity in the A antigenic content of red cells inside one individual sample. The most striking result was obtained with Aend phenotypes which appeared like A + O transmitted mosaicisms. However, heterogeneity was also observed, but to a lesser extent, among A3 and Ax RBC. The significance of this heterogeneity is discussed and used to explained the typical picture of agglutinability commonly observed with such red cells and anti-A antibodies. Qualitative difference were also studied by estimation of equilibrium constants (Ko) and thermodynamic parameters (delta Fo, delta Ho and delta So) associated with the binding of rabbit 125I-IgG anti-A molecules onto A RBC determinants. Only small variations of thermodynamic parameters were observed between each subgroup, but the high Ko values (greater than 10(8)M-1) measured, strongly suggest that "weak A" RBC determinants would process a common antigenic structure of the type: alpha-GalNAc (1 leads to 3) [alphaLFuc (1 leads to 2) beta Gal. However, the small differences of reactivity observed from one sample to an other could be related to slight variations in tridimensional configurations of oligosaccharides chains bearing the A specificity, associated with their variable antigenic content.  相似文献   

11.
Deregulation of chromatin assembly factor 1, p150 subunit A (CHAF1A) has recently been reported to be involved in the development of some cancer types. In this study, we identified that the frequency of positive CHAF1A staining in primary tumor mucosa (45.8%, 93 of 203 samples) was significantly elevated compared to that in paired normal mucosa (18.7%, 38 of 203 samples). The increased expression was strongly associated with cancer stage, tumor invasion, and histological grade. The five-year survival rate of patients with CHAF1A-positive tumors was remarkably lower than that of patients with CHAF1A-negative tumors. Colon cancer cells with CHAF1A knockdown exhibited decreased cell growth index, reduction in colony formation ability, elevated cell apoptosis rate as well as impaired colon tumorigenicity in nude mice. Hence, CHAF1A upregulation functions as a poor prognostic indicator of colon cancer, potentially contributing to its progression by mediating cancer cell proliferation.  相似文献   

12.
Most physiological and biological processes are regulated by endogenous circadian rhythms under the control of both a master clock, which acts systemically and individual cellular clocks, which act at the single cell level. The cellular clock is based on a network of core clock genes, which drive the circadian expression of non-clock genes involved in many cellular processes. Circadian deregulation of gene expression has emerged to be as important as deregulation of estrogen signaling in breast tumorigenesis. Whether there is a mutual deregulation of circadian and hormone signaling is the question that we address in this study. Here we show that, upon entrainment by serum shock, cultured human mammary epithelial cells maintain an inner circadian oscillator, with key clock genes oscillating in a circadian fashion. In the same cells, the expression of the estrogen receptor α (ER A) gene also oscillates in a circadian fashion. In contrast, ER A-positive and -negative breast cancer epithelial cells show disruption of the inner clock. Further, ER A-positive breast cancer cells do not display circadian oscillation of ER A expression. Our findings suggest that estrogen signaling could be affected not only in ER A-negative breast cancer, but also in ER A-positive breast cancer due to lack of circadian availability of ER A. Entrainment of the inner clock of breast epithelial cells, by taking into consideration the biological time component, provides a novel tool to test mechanistically whether defective circadian mechanisms can affect hormone signaling relevant to breast cancer.  相似文献   

13.
14.
CD8 T cell help for innate antitumor immunity   总被引:1,自引:0,他引:1  
Innate immunity is considered to initiate adaptive antitumor responses. We demonstrate that monoclonal CD8 T lymphocytes reactive to tumor Ag P1A on P815 mastocytoma cells provide essential "help" to NK cells for rejection of P1A-deficient tumors. RAG-deficient mice have normal NK cells but do not reject either tumor. Reconstitution of these mice with P1A-specific T cells conferred resistance to both P1A-expressing and -deficient tumor cells provided they were present at the same site. Elimination of Ag-negative tumor variants required both activated T and NK cells. Gene expression profiling of NK cells infiltrating P1A-positive tumors in mice with specific CD8 T cells demonstrated an activated effector phenotype. However, CD8 T cell help to NK cells appeared ineffective for P1A-negative variants separated from the P1A-positive tumor. Local tumor Ag-specific T cell-NK cell collaboration results in the elimination of tumor cells whether they express or not the T cell tumor Ag epitope, thus containing the emergence of tumor escape variants before metastasis.  相似文献   

15.
Quantitative flow cytometric analysis of ABO red cell antigens.   总被引:1,自引:0,他引:1  
R Sharon  E Fibach 《Cytometry》1991,12(6):545-549
A flow cytometry method has been employed to quantitatively compare the expression of A, B and H antigens on various red blood cells (RBC). The H substance was directly labelled by fluorescein-conjugated anti-H lectin and the A and B antigens by indirect staining first with monoclonal anti-A or anti-B antibodies followed by fluorescently, fluorescein (FITC) or phycoerythrin (PE), labelled anti-mouse immunoglobulin (Ig) antibodies. More than a ten-fold difference in cellular fluorescence intensity was found within each sample. Both the percentage and the mean fluorescence of the positive subpopulation for each antigen were determined. Each RBC population was characterized with respect to the expression of A, B or H antigen by a compound mean value that was the calculated product of these two parameters. The results demonstrated a reciprocal relationship between the compound means of A or B and H. The ratio of A/H or B/H was found to be most informative. Homozygotes for A or B had ratios of greater than 200 and greater than 30, respectively, while heterozygotes (AO or BO) had ratios of less than 5. This method could also distinguish between A1 and A2; RBC carrying the A1 phenotype (as determined by agglutination with anti-A1 lectin) showed a higher A/H ratio than those carrying A2. In contrast to the reciprocity in the expression of A (or B) and H found in RBC obtained from different individuals, a direct correlation was found in the expression of these antigens by individual cells within a given population.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

16.
Results of the screening of aberrant (paradoxal) secretors in 14372 healthy donors and 614 patients with ulcus duodeni are presented. An extremely high frequency of aberrant secretors was established (12.6%) in patients with ulcus duodeni in comparison to donors (0.10%). A new type of aberrant secretors was registered in patients of A1 and A1B blood groups. Their salivas normally inhibited anti-A sera, but the expected inhibition of anti-A1 reagents (dolichos biflorus) could not be observed. The data of comparative quantitative investigations of the inhibiting strength of the ABH antigen in salivas of normal secretors, nonsecretors and aberrant secretors are presented. Various theoretical explanations of aberrant secretors are discussed.  相似文献   

17.
It has been demonstrated with the help of intravenous in-vivo immunization with irradiated splenocytes of A.AL anti-A.TL (difference at the K-region of H-2), A. TH anti-A. TL and A. TL anti-A. TH (difference at the I-region of H-2), C57BL/10Sn anti-B10.D2(R107) and B10.D2 (R107) anti-C57BL/10Sn (difference at the D-region of H-2) mice that T cells--MIF producers, induced at different times after induction of the alloimmune response, react to the products of the K- and I- but not to those of the D-region of the H-2 complex.  相似文献   

18.
19.
MUC3A is a membrane-bound glycoprotein that is aberrantly expressed in carcinomas and is a risk factor for a poor prognosis. However, the exact mechanism of MUC3A expression has yet to be clarified. Here, we provide the first evidence that MUC3A gene expression is controlled by the CpG methylation status of the proximal promoter region. We show that the DNA methylation pattern is intimately correlated with MUC3A expression in breast, lung, pancreas and colon cancer cell lines. The DNA methylation status of 30 CpG sites from −660 to +273 was mapped using MassARRAY analysis. MUC3A-negative cancer cell lines and those with low MUC3A expression (e.g., MCF-7) were highly methylated in the proximal promoter region, corresponding to 9 CpG sites (−345 to −75 bp), whereas MUC3A-positive cell lines (e.g., LS174T) had low methylation levels. Moreover, 5-aza-2′-deoxycytidine and trichostatin A treatment of MUC3A-negative cells or those with low MUC3A expression caused elevation of MUC3A mRNA. Our results suggest that DNA hypomethylation in the 5′-flanking region of the MUC3A gene plays an important role in MUC3A expression in carcinomas of various organs. An understanding of epigenetic changes in MUC3A may contribute to the diagnosis of carcinogenic risk and to prediction of outcome in patients with cancer.  相似文献   

20.
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