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71.
Wang BY Boag AH Idrees M Young ID Unger PD 《Archives of pathology & laboratory medicine》2004,128(4):456-459
Pathologic processes involving the urachus are usually related to inflammatory or sinofistular conditions. Neoplasms rarely arise within this structure, and when they do occur, they are typically epithelial, with mucinous adenocarcinoma being the most common. Mesenchymal lesions, both benign and malignant, have rarely been described in this location. We report the case of a 66-year-old white man who presented with a primary urachal malignant fibrous histiocytoma and died of metastatic disease 20 months after the initial diagnosis. This is an unusual case of malignant fibrous histiocytoma arising in a urachal remnant. 相似文献
72.
Human and Murine Immune Responses to a Novel Leishmania major Recombinant Protein Encoded by Members of a Multicopy Gene Family 总被引:1,自引:0,他引:1 下载免费PDF全文
John R. Webb Antonio Campos-Neto Pamela J. Ovendale Tricia I. Martin Erika J. Stromberg Roberto Badaro Steven G. Reed 《Infection and immunity》1998,66(7):3279-3289
Vaccination of BALB/c mice with Leishmania major promastigote culture filtrate proteins plus Corynebacterium parvum confers resistance to infection with L. major. To define immunogenic components of this protein mixture, we used sera from vaccinated mice to screen an L. major amastigote cDNA expression library. One of the immunoreactive clones thus obtained encoded a novel protein of L. major with a molecular mass of 22.1 kDa. The predicted amino acid sequence of this clone exhibited significant homology to eukaryotic thiol-specific-antioxidant (TSA) proteins. Therefore, we have designated this protein L. major TSA protein. Southern blot hybridization analyses indicate that there are multiple copies of the TSA gene in all species of Leishmania analyzed. Northern blot analyses demonstrated that the TSA gene is constitutively expressed in L. major promastigotes and amastigotes. Recombinant TSA protein containing an amino-terminal six-histidine tag was expressed in Escherichia coli with the pET17b system and was purified to homogeneity by affinity chromatography. Immunization of BALB/c mice with recombinant TSA protein resulted in the development of strong cellular immune responses and conferred protective immune responses against infection with L. major when the protein was combined with interleukin 12. In addition, recombinant TSA protein elicited in vitro proliferative responses from peripheral blood mononuclear cells of human leishmaniasis patients and significant TSA protein-specific antibody titers were detected in sera of both cutaneous-leishmaniasis and visceral-leishmaniasis patients. Together, these data suggest that the TSA protein may be useful as a component of a subunit vaccine against leishmaniasis. 相似文献
73.
74.
Two variants of a continuous recognition training procedure were designed in order to query 2 forms of spatial memory. A continuous reinforcement condition (reflecting perceptual memory) and a differential reinforcement condition (reflecting episodic-like memory) were used to test rats on a 12-arm radial maze. After total hippocampal lesions, rats demonstrated intact performance on the continuous reinforcement condition, but impaired performance on the differential reinforcement condition. After parietal lesions, rats demonstrated the reverse pattern of performance: impaired performance on the continuous reinforcement condition and intact performance on the differential reinforcement condition. Thus, a double dissociation appears to exist between parietal cortex and hippocampus for the continuous reinforcement condition (reflecting perceptual memory) versus the differential reinforcement condition (reflecting episodic memory) for spatial location information. 相似文献
75.
76.
Salmena L Lemmers B Hakem A Matysiak-Zablocki E Murakami K Au PY Berry DM Tamblyn L Shehabeldin A Migon E Wakeham A Bouchard D Yeh WC McGlade JC Ohashi PS Hakem R 《Genes & development》2003,17(7):883-895
Defects in death receptor-mediated apoptosis have been linked to cancer and autoimmune disease in humans. The in vivo role of caspase 8, a component of this pathway, has eluded analysis in postnatal tissues because of the lack of an appropriate animal model. Targeted disruption of caspase 8 is lethal in utero. We generated mice with a targeted caspase 8 mutation that is restricted to the T-cell lineage. Despite normal thymocyte development in the absence of caspase 8, we observed a marked decrease in the number of peripheral T-cells and impaired T-cell response ex vivo to activation stimuli. caspase 8 ablation protected thymocytes and activated T-cells from CD95 ligand but not anti-CD3-induced apoptosis, or apoptosis activated by agents that are known to act through the mitochondria. caspase 8 mutant mice were unable to mount an immune response to viral infection, indicating that caspase 8 deletion in T-cells leads to immunodeficiency. These findings identify an essential, cell-stage-specific role for caspase 8 in T-cell homeostasis and T-cell-mediated immunity. This is consistent with the recent identification of caspase 8 mutations in human immunodeficiency. 相似文献
77.
Ursula R. Kees Jette Ford Pamela R. Ranford Susanne E. Peroni Jaclyn A. Biegel Annette H. Parmiter Lavinia A. Hallam Michael L. N. Willoughby Dominic Spagnolo 《Genes, chromosomes & cancer》1994,9(2):129-135
We have established two cell lines, PER-452 and PER-453, from an 8-month-old girl with an extensive pineoblastoma. Characterization of these lines revealed that the proto-oncogenes MYC and MYCN were not amplified, but both cell lines showed MYCN expression comparable to a cell line with 200-fold MYCN amplification. Both cell lines contained an i( 17q). These results support the concept that pineoblastomas belong to a larger group of primitive neuroectodermal tumors of the central nervous system. These two cell lines provide a unique opportunity to investigate the molecular genetic mechanisms underlying these neoplasms further. Genes Chrom Cancer 9:129-135 (1994).© 1994 Wiley-Liss, Inc. 相似文献
78.
Thomas W. Prior Gail D. Wenger Audrey C. Papp Pamela J. Snyder Mary S. Sedra Claire Bartolo Jay W. Moore W. Edward Highsmith 《Human mutation》1995,5(3):263-268
A new strategy has been developed for rapid haplotype analysis based on an initial multiplex amplification of several polymorphic sites, followed by heteroduplex detection. Heteroduplexes formed between two different alleles are detected because they migrate differently than the corresponding homoduplexes in Hydrolink-MDE gel. This simple, rapid method does not depend on specific sequences such as restriction enzyme sites or CA boxes and does not require the use of isotope. This approach has been tested using commonly occurring polymorphisms spanning the dystrophin gene as a model. We describe the use of the method to assign the carrier status of females in Duchenne muscular dystrophy (DMD) pedigrees. The method may be used for other genetic diseases when mutations are unknown or there are few dinucleotide markers in the gene proximity, and for the identification of haplotype backgrounds of mutant alleles. © 1995 Wiley-Liss, Inc. 相似文献
79.
Pamela Christudoss R. Selvakumar Anna B. Pulimood Jude Joseph Fleming George Mathew 《Experimental and toxicologic pathology》2008,59(5):313-318
Alterations in tissue zinc levels have been documented in patients with gastrointestinal tract malignancies and more frequently, in those with colonic cancer. However, the precise role of tissue zinc in carcinogenesis is not well elucidated. This study, using a well-established colon cancer model in rats, was designed to investigate the relationship of tissue zinc to the carcinogenic process. The aim was to examine tissue zinc levels in the preneoplastic tissues and to study the changes that occur during transition of mucosa from normal to preneoplastic state. Six-week old rats were given a single dose subcutaneous injection of azoxymethane (AOM) (30mg/kg body weight) and sacrificed after 1, 2, 5, and 9 months of the treatment. Plasma zinc levels showed a significant decrease (p<0.05) at 9 months compared with controls. Tissue zinc levels showed a significant decrease in the large intestine at 1 and 2 months (p<0.05) and at 5 and 9 months (p<0.01), in the small intestine at 2, 5, and 9 months (p<0.05), and in the stomach at 5 and 9 months (p<0.05). The maximum percent decrease (45%) in tissue zinc was observed in the large intestine at 9 months. Tissue copper zinc super oxide dismutase (CuZnSOD) activity was assessed in the body of the stomach, small intestine, and large intestine and compared with the control group. There was a significant fall in CuZnSOD levels in the small intestine at 9 months (p<0.05) and in the large intestine at 5 and 9 months (p<0.01). Two of these six rats showed histological evidence of precancerous lesions in the mucosa of the colon. This study suggests that the decrease in plasma zinc, tissue zinc and activity of CuZnSOD is associated with development of preneoplastic lesions in the colonic mucosa. 相似文献
80.
了解TGFβ1基因对血管内皮细胞表达细胞外基质蛋白及与基质黏附力的影响。用DOTAP脂质体转染p MAMneo TGFβ1于原代培养的脐静脉内皮细胞,经G4 18筛选,TGFβ1表达经免疫荧光鉴定。Western blot确定 型胶原、纤黏连蛋白的表达,微管吸吮系统确定内皮细胞与基质的黏附力。结果表明生理情况下的内皮细胞能表达少量的TGFβ1及胶原、纤黏连蛋白。经G4 18筛选,外源性TGFβ1在血管内皮细胞中稳定表达,能显著提高胶原、纤黏连蛋白纤维的表达及细胞与基质的黏附。说明TGFβ1在血管组织工程中促进内皮细胞的黏附具有一定的应用价值。 相似文献