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71.
Analysis of orthologous gene expression between human pulmonary adenocarcinoma and a carcinogen-induced murine model 下载免费PDF全文
Stearman RS Dwyer-Nield L Zerbe L Blaine SA Chan Z Bunn PA Johnson GL Hirsch FR Merrick DT Franklin WA Baron AE Keith RL Nemenoff RA Malkinson AM Geraci MW 《The American journal of pathology》2005,167(6):1763-1775
Human adenocarcinoma (AC) is the most frequently diagnosed human lung cancer, and its absolute incidence is increasing dramatically. Compared to human lung AC, the A/J mouse-urethane model exhibits similar histological appearance and molecular changes. We examined the gene expression profiles of human and murine lung tissues (normal or AC) and compared the two species' datasets after aligning approximately 7500 orthologous genes. A list of 409 gene classifiers (P value <0.0001), common to both species (joint classifiers), showed significant, positive correlation in expression levels between the two species. A number of previously reported expression changes were recapitulated in both species, such as changes in glycolytic enzymes and cell-cycle proteins. Unexpectedly, joint classifiers in angiogenesis were uniformly down-regulated in tumor tissues. The eicosanoid pathway enzymes prostacyclin synthase (PGIS) and inducible prostaglandin E(2) synthase (PGES) were joint classifiers that showed opposite effects in lung AC (PGIS down-regulated; PGES up-regulated). Finally, tissue microarrays identified the same protein expression pattern for PGIS and PGES in 108 different non-small cell lung cancer biopsies, and the detection of PGIS had statistically significant prognostic value in patient survival. Thus, the A/J mouse-urethane model reflects significant molecular details of human lung AC, and comparison of changes in orthologous gene expression may provide novel insights into lung carcinogenesis. 相似文献
72.
DNA microarray analysis reveals novel gene expression profiles in collagen-induced arthritis 总被引:4,自引:0,他引:4
Thornton S Sowders D Aronow B Witte DP Brunner HI Giannini EH Hirsch R 《Clinical immunology (Orlando, Fla.)》2002,105(2):155-168
Global gene expression was analyzed in early and late collagen-induced arthritis (CIA). Of 8734 cDNAs analyzed, 330 were induced and 55 downregulated greater than twofold in early or late disease. Hierarchical clustering of these 385 cDNAs demonstrated five distinct expression patterns differentiating early from late disease and correlating with histopathologic changes in the paw. Of the 385 cDNAs, 185 are known, characterized genes, the majority of which are not described as playing a role in arthritis. However, several of these genes are involved in pathological processes relating to arthritis, including apoptosis, inflammation, and cellular proliferation. One interesting gene, follistatin-like gene, is highly expressed along the margin of contact between inflammatory synovial pannus and eroding bone, suggesting a role in joint destruction. These results demonstrate that global gene expression profiles distinguish early and late CIA and reveal several genes novel to arthritis the further characterization of which will advance our understanding of arthritis. 相似文献
73.
Ogawa M Fraser S Fujimoto T Endoh M Nishikawa S Nishikawa SI 《International reviews of immunology》2001,20(1):21-44
It has been widely accepted that hematopoietic and endothelial cell lineages diverge from a common progenitor referred to as the hemangioblast. Recently, analyses of the potential of progenitor cells purified from mouse embryos as well as embryonic stem cells differentiating in vitro resolved intermediate stages between mesodermal cells and committed precursors for hematopoietic and endothelial cell lineages. There are two distinct hematopoietic cell lineages which have different origins, i.e., primitive hematopoietic lineage derived from mesoderm or hemangioblasts and definitive hematopoietic lineage derived from endothelial cells. The endothelium is suggested to provide a milieu in which the definitive hematopoietic lineage acquires multiple potentials. 相似文献
74.
Use of modified resistogram to type Candida albicans isolated from cases of vaginitis and from faeces in the same geographical area. 总被引:1,自引:0,他引:1 下载免费PDF全文
Ninety strains of Candida albicans were isolated from vaginal swabs taken by general practitioners from cases of vaginal candidosis. One hundred and nine strains were also isolated from 300 specimens of faeces received from outpatients living in the same geographical area. These strains were typed using a modification of the resistotyping method. We were unable to find any significant differences between the two populations of strains. This suggests that no particular resistotype has an increased ability to cause vaginitis. 相似文献
75.
The effect of subclinical infection with lymphoid leukosis virus (LLV) on the productivity traits of layer hens was investigated. In hens that shed gs-antigen of LLV to albumen, onset of sexual maturity was delayed by a mean of 11 days and the number of eggs laid was reduced -by 68 per hen up to 75 weeks of age. Shedding hens laid on average 2 g lighter eggs and of lesser specific gravity. Thirty-four % less chickens were obtained in the reproduction programmes from LLV-shedders in comparison with non-shedders. LLV had no significant effect on fertility and hatchability. Reduced egg-related performance was only directly related to LLV-shedding and dams' shedding status had no effect on the egg-related performance of their LLV-free progeny. Dams' shedding status, however, correlated with higher mortality (10% higher) among their progeny. The percentage of non-layers was also higher in progeny of LLV-shedders. Meconia were highly suitable samples for identifying both transmitting dams and infected chickens but only if the test for infectious virus was performed. ELISA on meconia was less reliable than the test for virus and therefore is not recommended for the detection of residual of infected chickens in the flocks selected for reduced gs-antigen shedding. 相似文献
76.
Greta A. B. Edelstam Ulla B. G. Laurent Örjan E. Lundkvist J. Robert E. Fraser Toryard C. Laurent 《Inflammation》1992,16(5):459-469
Aseptic peritonitis was induced in rabbits by intraperitoneal injection of irritating agents, mainly starch suspensions. The inflammatory response was followed in the peritoneal lavage fluid by cell counts (average increase about 800-fold the first day) and hyaluronan concentration (average increase about 200-fold on the second and third days). The turnover rate of hyaluronan was studied by injecting tritium-labeled hyaluronan intraperitoneally and by following the appearance of tritiated water in serum. In control animals given trace amounts of hyaluronan, half-lives of 1–14 h were recorded. When the labeled polysaccharide had been mixed with 10 mg/ml of unlabeled hyaluronan, the half-life was approximately one day. Rabbits with ongoing peritonitis exhibited half-lives between 1 and 16 h. It was concluded that there was a large individual variation in uptake kinetics, that the removal process could be receptor mediated, and that the increase in intraperitoneal hyaluronan in peritonitis mainly was due to an increased production of the polysaccharide rather than a decreased rate of removal. 相似文献
77.
78.
Leslie G. Dodd Douglas B. Evans Fraser Symmans Ruth L. Katz 《Diagnostic cytopathology》1994,10(4):371-374
We report two cases of extramedullary plasmacytoma (EMP) of the pancreas, diagnosed by fine-needle aspiration (FNA). Plasmacytoma of the pancreas is a rare neoplasm with only 12 cases recorded in the literature. Because of its scarcity and the cytomorphologic similarity between plasma cells and endocrine cells, EMP of the pancreas may be confused with neuroendocrine (islet cell) tumors of the pancreas. Immunohistochemical staining for light chain and/or neuroendocrine markers will prevent diagnostic error when interpreting plasmacytoid neoplasms of any site susceptible to endocrine tumors, including the pancreas. © 1994 Wiley-Liss, Inc. 相似文献
79.
Sarraf S Tejada R Abawi M Oberst M Dennis T Simon KC Blancato J 《Cancer Genetics and Cytogenetics》2005,161(1):63-69
Cell lines derived from tumors contain numerous chromosomal aberrations and are the focus of study in tumor evolution. The ovarian teratocarcinoma cell line PA-1 demonstrates a single chromosomal aberration: a reciprocal t(15;20)(p11.2;q11.2). A complete molecular genetic analysis was undertaken to characterize this cell line. The PA-1 cell line was studied with fluorescence in situ hybridization (FISH), spectral karyotyping (SKY), bacterial artificial chromosome (BAC) microarray, and Western blotting. Amplification of 20q is frequently implicated in both breast and ovarian cancer; this region contains a number of oncogenes including MDM2, ZNF217, and the ovarian tumor marker WFDC2 (alias HE4). FISH revealed gene amplification of AIB1 (now known as NCOA3) but not STK15 (now known as AURKA). Immunoblot analysis demonstrated 3.6-fold overexpression of the AIB1 protein product, but no elevation of the STK15. BAC cancer gene microarray analysis showed gene amplification of > or =1.20 for five oncogenes. The presence of a consistent single change in PA-1, the t(15;20)(p11.2;q11.2), suggests that the aberration is significant with respect to the transformation status of the cell line. This translocation appears to cause overexpression of AIB1 (and perhaps other proteins), which may provide an immortalizing effect on this cell line. 相似文献
80.
A new physical assay method for tobacco mosaic virus is described which incorporates two improvements on previous procedures. Losses of up to 75% of virus during extraction are corrected by adding a trace of radioactive virus to leaf samples before homogenization, and determining percentage recovery of radioactivity in final virus preparations. Estimation of virus concentration in partially purified preparations is from the first derivative (dA/d lambda) of the ultraviolet absorption spectrum, using a pronounced signal from the tryptophan fine-structure absorption band at 285-293 nm. This method is highly insensitive to ultraviolet-absorbing contaminants, which cause errors and increase variation between replicates, when estimation of virus concentration is by normal measurement of ultraviolet absorption (A260). The method can be applied to at least some other viruses. 相似文献