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151.
To analyze the mechanisms of increased nonspecific immunity in pregnant women, the effect of various hormones on the phagocytic activity was estimated by a luminol-dependent chemiluminescence (CL) response during phagocytosing opsonized zymosan. The CL response of whole blood supplemented with exogenous human chorionic gonadotropin (hCG) increased significantly in all the male and female subjects and pregnant women. An approximate two- to fourfold increase was observed in comparison with the unsupplemented control in each subject at concentrations ranging from 1 to 1,000 IU/ml after 48 h of incubation (P less than 0.05). Progesterone slightly stimulated the CL response in female subjects only, but had no effect on male and pregnant women. Estradiol (E2) did not stimulate the CL response in any subject. The expression of Fc and C3b receptors on the surface of polymorphonuclear leucocytes (PMNL) in pregnant women was also investigated by measuring the immunofluorescence stained with monoclonal antibody to Fc and C3b receptors, respectively. The relative numbers of Fc receptors increased significantly in the third trimester compared to those of female control (P less than 0.05). Those of C3b receptor also increased in the second and third trimester (P less than 0.005). These results suggested that the nonspecific immunity represented by phagocytic activity in pregnant women increased with both oxidative metabolic responsiveness and the expression of membrane receptors. Besides, the increased phagocytic activity of the maternal host is probably due to the stimulatory effect of both endogenous and exogenous hCG on their peripheral blood phagocytes.  相似文献   
152.
表达前列腺特异性膜抗原的DNA疫苗对肿瘤细胞的抑制作用   总被引:3,自引:0,他引:3  
目的构建表达前列腺特异性膜抗原(PSMA)的DNA疫苗,观察其在体外对肿瘤细胞的免疫攻击和在体内对肿瘤细胞攻击的免疫保护作用。方法通过稳定转染构建表达PSMA的小鼠黑色素瘤细胞系B16-PSMA,将DNA疫苗pCDNA3.1-PSMA通过肌肉注射导入C57BL/6小鼠体内,分离小鼠脾细胞,检测细胞毒性T淋巴细胞(cytotoxic T lymphocytes,CTL)反应。以B16-PSMA细胞攻击免骺小鼠,观察免疫动物的无瘤生存期和肿瘤体积增长情况,评价DNA疫苗的抗肿瘤作用。结果DNA疫苗可诱导小鼠脾淋巴细胞CTL活性,经过免疫后的小鼠成瘤率降低,无瘤生存期延长,肿瘤生长缓慢,肿瘤组织内有较多淋巴细胞浸润,表明产生较强的抗肿瘤反应。结论表达PSMA的DNA疫苗能够诱导小鼠产生特异性免疫反应,对表达PSMA的肿瘤细胞的攻击产生免疫保护作用,为前列腺癌的预防和免疫治疗提供了新的思路。  相似文献   
153.
Aims : Synovial sarcomas are rare tumours occasionally arising in the pleural cavity, a site where their histological characteristics may be mistaken for those of malignant mesothelioma. We examined three cases of primary pleural synovial sarcoma in order to look for clinicopathological features that may help in distinguishing them from both mesotheliomas and other sarcomas that may arise in the pleura.  

Methods and results


All three patients were male, aged 42, 28 and 42, respectively, and had no known exposure to asbestos. One biphasic tumour contained neutral mucin in focal epithelial elements that also stained positively for BerEP4 and AUA1. All three tumours showed focal positivity for either keratin or EMA in the sarcomatous elements, and they also stained positively for bcl-2 protein and MIC2 gene product (CD99).  

Conclusions


Our results emphasize the importance of being aware of synovial sarcoma as a possible primary pleural malignancy, especially in a young patient with a localized mass. In addition, the presence of bcl-2 protein perhaps represents a useful marker in distinguishing synovial sarcoma, especially monophasic variants, from mesothelioma within a panel of antibodies.  相似文献   
154.
Twenty-six intracranial germ cell tumours (11 germinomas, 10 teratomas, 2 endodermal sinus tumours, 1 teratocarcinoma, and 2 undifferentiated embryonal carcinomas) and 26 gonadal germ cell tumours (13 testicular seminomas, 2 ovarian dysgerminomas, 9 ovarian teratomas, and 2 myometrial choriocarcinomas) were studied by immunoperoxidase with monoclonal antibodies (MAbs) against epithelial membrane antigen (EMA), cytokeratin, and vimentin. Typical tumour cells in three of the 11 germinomas (two of the latter being situated in the posterior fossa) expressed both EMA and cytokeratin, whereas those in the seminomas and dysgerminomas did not. In one seminoma, a few multinucleated giant cells expressed cytokeratin. In three of seven germinomas, vimentin-positive tumour cells were found, but all seminomas and dysgerminomas were negative. In the other forms of intracranial and gonadal germ cell tumours, epithelial and mesenchymal elements displayed the expected patterns of immunoreactivity to the respective determinants. The immunoperoxidase differences between the intracranial germinomas and their gonadal equivalents indicate that, in the former, early epithelial or mesenchymal differentiation of the primordial germ cells may be present. The findings draw attention to the heterogeneous cellular composition of these otherwise morphologically homogeneous-appearing tumours and, especially in the posterior fossa, to their transitional links to the immature teratomas.  相似文献   
155.
本文探讨增强胚胎胸腺细胞抗肿瘤效应的方法。采用食管癌细胞膜抗原体外诱导培养的胚胎胸腺细胞 ;用3 H TdR掺入法检测其对食管癌细胞的细胞毒效应 ;用SP 免疫组化法检测其经诱导后细胞表面抗原的变化。结果经食管癌细胞膜抗原诱导 3~ 9d的胚胎胸腺细胞对食管癌细胞的杀伤率明显大于未经诱导的胚胎胸腺细胞 ;胚胎胸腺细胞经诱导后CD4 + /CD8+ 细胞无明显变化 ,但诱导后出现少量CD5 6细胞。食管癌细胞膜抗原体外诱导胚胎胸腺细胞可增强其对食管癌细胞的细胞毒作用  相似文献   
156.
Previous results indicated that the herpes simplex virus 1 (HSV-1) U(L)31 gene is necessary and sufficient for localization of the U(L)34 protein exclusively to the nuclear membrane of infected Hep2 cells. In the current studies, a bacterial artificial chromosome containing the entire HSV-1 strain F genome was used to construct a recombinant viral genome in which a gene encoding kanamycin resistance was inserted in place of 262 codons of the 306 codon U(L)31 open reading frame. The deletion virus produced virus titers approximately 10- to 50-fold lower in rabbit skin cells, more than 2000-fold lower in Vero cells, and more than 1500-fold lower in CV1 cells, compared to a virus bearing a restored U(L)31 gene. The replication of the U(L)31 deletion virus was restored on U(L)31-complementing cell lines derived either from rabbit skin cells or CV1 cells. Confocal microscopy indicated that the majority of U(L)34 protein localized aberrantly in the cytoplasm and nucleoplasm of Vero cells and CV1 cells, whereas U(L)34 protein localized at the nuclear membrane in rabbit skin cells, and U(L)31 complementing CV1 cells infected with the U(L)31 deletion virus. We conclude that rabbit skin cells encode a function that allows proper localization of U(L)34 protein to the nuclear membrane. We speculate that this function partially complements that of U(L)31 and may explain why U(L)31 is less critical for replication in rabbit skin cells as opposed to Vero and CV1 cells.  相似文献   
157.
Pseudoxanthoma elasticum (PXE) is a systemic heritable disorder that affects the elastic tissue in the skin, eye, and cardiovascular system. Mutations in the ABCC6 gene cause PXE. We performed a mutation screen in ABCC6 using haplotype analysis in conjunction with direct sequencing to achieve a mutation detection rate of 97%. This screen consisted of 170 PXE chromosomes in 81 families, and detected 59 distinct mutations (32 missense, eight nonsense, and six likely splice-site point mutations; one small insertion; and seven small and five large deletions). Forty-three of these mutations are novel variants, which increases the total number of PXE mutations to 121. While most mutations are rare, three nonsense mutations, a splice donor site mutation, and the large deletion comprising exons 23-29 (c.2996_4208del) were identified as relatively frequent PXE mutations at 26%, 5%, 3.5%, 3%, and 11%, respectively. Chromosomal haplotyping with two proximal and two distal polymorphic markers flanking ABCC6 demonstrated that most chromosomes that carry these relatively frequent PXE mutations have related haplotypes specific for these mutations, which suggests that these chromosomes originate from single founder mutations. The types of mutations found support loss-of-function as the molecular mechanism for the PXE phenotype. In 76 of the 81 families, the affected individuals were either homozygous for the same mutation or compound heterozygous for two mutations. In the remaining five families with one uncovered mutation, affected showed allelic compound heterozygosity for the cosegregating PXE haplotype. This demonstrates pseudo-dominance as the relevant inheritance mechanism, since disease transmission to the next generation always requires one mutant allelic variant from each parent. In contrast to other previous clinical and molecular claims, our results show evidence only for recessive PXE. This has profound consequences for the genetic counseling of families with PXE.  相似文献   
158.
A rare case of primary pulmonary synovial sarcoma with polypoid endobronchial growth in a 42-year-old Japanese woman is described. Left upper sleeve lobectomy was performed for the polypoid tumor measuring 2.5 cm in the left major bronchus and the patient was treated with adjuvant chemotherapy. Three years later, a recurrent tumor was discovered. Microscopically, this tumor was characterized by a proliferation of oval to spindle-shaped cells arranged in sheets and fascicles and covered by the thin normal bronchial epithelium. Immunohistochemically, tumor cells were positive for vimentin, and focally positive for pancytokeratin recognized by AE1/AE3, cytokeratin 7 and epithelial membrane antigen. A chimera gene, SYT-SSX1, was detected. Recently, primary pulmonary synovial sarcoma is an increasingly recognized clinical entity; however, most of these tumors present as a parenchymal mass. The present case is a unique example of primary synovial sarcoma of endobronchial polypoid type. This case suggests that pulmonary synovial sarcoma might originate from bronchial submucosal stromal tissue.  相似文献   
159.
PROBLEM: The unusual pattern of human leukocyte antigen (HLA) expression on human trophoblasts could play an important role in successful pregnancy outcome. To determine whether alterations in HLA expression are associated with pregnancy abnormalities we have investigated expression of these antigens on chorionic and extravillous cytotrophoblasts. METHODS: Frozen tissue sections of placenta and fetal membranes were collected after pre-term spontaneous delivery, severe pre-eclampsia pre-term Caesarean section, normal term delivery and term Caesarean section. HLA expression was analyzed by immunohistochemistry. RESULTS: We did not observe differences in the expression of HLA on chorionic and extravillous cytotrophoblasts in pregnancy abnormalities. However, we noted higher expression levels of HLA class Ia molecules in amnion epithelial cells in pre-term deliveries. Furthermore, in severe pre-eclampsia the number of extravillous cytotrophoblast islands were elevated when compared with pre-term deliveries. CONCLUSIONS: No alterations in expression of HLA class Ia, HLA-G and HLA class II on human trophoblasts in pregnancy abnormalities were seen.  相似文献   
160.
Summary Diabetic late complications are characterized by morphological and biochemical alterations of the extracellular matrix. In particular, longstanding diabetes causes quantitative and qualitative changes in basement membrane structure of retinal and renal capilleries. Immunohistochemical investigations of diabetic kidneys with diffuse glomerulosclerosis show increased collagen type IV deposition in the mesangial matrix and decreased heparan sulfate proteoglycan content in the mesangial matrix and glomerular basement membrane as well. In nodular glomerulosclerosis normal basement membrane components are decreased or absent while the occurrence of collagen type III in this stage has been interpreted as an irreversible alteration of the glomerular structure. These changes seem to be the underlying cause for the alterations in renal functions like persistent albuminuria and proteinuria. Increased intra- and extracellular levels of glucose and its derivatives are thought to be responsible for diabetic tissue dysfunction although there are reports on possible genetic defects causing increased susceptibility to develop diabetic nephropathy. Recent results, however, focuse on the role of glucose-induced cytokine secretion as mediator for altered metabolism of glomerular matrix proteins. In vitro studies with cultured kidney cells have shown that the glucose-induced dysregulation of the basement membrane synthesis may be mediated by a glucose dependent activation of protein kinase C. Alternatively or synergistically, the formation of AGE products formed after prolonged exposure of matrix proteins to elevated glucose may also lead to cytokine secretion subsequently inducing synthesis of extracellular matrix proteins. Studies in experimental animals confirm the diabetes induced dysregulation of the synthesis of extracellular matrix components on the molecular level.Abbreviations HSPG heparan sulfate proteoglycan - GBM glomerular basement membrane - ECM extracellular matrix - AGE advanced glucosylation end products - TNF tumor necrosis factor - bFGF basic fibroblast growth factor  相似文献   
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