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991.
Thorgaard GH Bailey GS Williams D Buhler DR Kaattari SL Ristow SS Hansen JD Winton JR Bartholomew JL Nagler JJ Walsh PJ Vijayan MM Devlin RH Hardy RW Overturf KE Young WP Robison BD Rexroad C Palti Y 《Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology》2002,133(4):609-646
The rainbow trout (Oncorhynchus mykiss) is one of the most widely studied of model fish species. Extensive basic biological information has been collected for this species, which because of their large size relative to other model fish species are particularly suitable for studies requiring ample quantities of specific cells and tissue types. Rainbow trout have been widely utilized for research in carcinogenesis, toxicology, comparative immunology, disease ecology, physiology and nutrition. They are distinctive in having evolved from a relatively recent tetraploid event, resulting in a high incidence of duplicated genes. Natural populations are available and have been well characterized for chromosomal, protein, molecular and quantitative genetic variation. Their ease of culture, and experimental and aquacultural significance has led to the development of clonal lines and the widespread application of transgenic technology to this species. Numerous microsatellites have been isolated and two relatively detailed genetic maps have been developed. Extensive sequencing of expressed sequence tags has begun and four BAC libraries have been developed. The development and analysis of additional genomic sequence data will provide distinctive opportunities to address problems in areas such as evolution of the immune system and duplicate genes. 相似文献
992.
993.
Burgess S Walker M Wang F Sellers JR White HD Knight PJ Trinick J 《The Journal of cell biology》2002,156(6):983-991
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995.
Higgins JP Wang L Kambham N Montgomery K Mason V Vogelmann SU Lemley KV Brown PO Brooks JD van de Rijn M 《Molecular biology of the cell》2004,15(2):649-656
The kidney is a highly specialized organ with a complex, stereotyped architecture and a great diversity of functions and cell types. Because the microscopic organization of the nephron, the functional unit of the kidney, has a consistent relationship to the macroscopic anatomy of the kidney, knowledge of the characteristic patterns of gene expression in different compartments of the kidney could provide insight into the functions and functional organization of the normal nephron. We studied gene expression in dissected renal lobes of five adult human kidneys using cDNA microarrays representing approximately 30,000 different human genes. Total RNA was isolated from sections of the inner and outer cortex, inner and outer medulla, papillary tips, and renal pelvis and from glomeruli isolated by sieving. The results revealed unique and highly distinctive patterns of gene expression for glomeruli, cortex, medulla, papillary tips, and pelvic samples. Immunohistochemical staining using selected antisera confirmed differential expression of several cognate proteins and provided histological localization of expression within the nephron. The distinctive patterns of gene expression in discrete portions of the kidney may serve as a resource for further understanding of renal physiology and the molecular and cellular organization of the nephron. 相似文献
996.
Calorie restriction slows aging and increases life span in many organisms. In yeast, a mechanistic explanation has been proposed whereby calorie restriction slows aging by activating Sir2. Here we report the identification of a Sir2-independent pathway responsible for a majority of the longevity benefit associated with calorie restriction. Deletion of FOB1 and overexpression of SIR2 have been previously found to increase life span by reducing the levels of toxic rDNA circles in aged mother cells. We find that combining calorie restriction with either of these genetic interventions dramatically enhances longevity, resulting in the longest-lived yeast strain reported thus far. Further, calorie restriction results in a greater life span extension in cells lacking both Sir2 and Fob1 than in cells where Sir2 is present. These findings indicate that Sir2 and calorie restriction act in parallel pathways to promote longevity in yeast and, perhaps, higher eukaryotes. 相似文献
997.
Oshima T Blaschuk O Gour B Symonds M Elrod JW Sasaki M Jackson TH Alexander JS 《Life sciences》2003,73(13):1729-1740
Occludin is an integral membrane protein within tight junctions. Previous studies suggest it functions as a sealing element, which promotes barrier in endothelial and epithelial cell layers. Here, we examine the role of occludin in neutrophil chemotaxis, using cyclic occludin peptide antagonists that incorporate a conserved occludin cell adhesion recognition (CAR) sequence. Human umbilical vein endothelial cells were pre-treated with occludin specific cyclic peptide antagonists to examine effects on neutrophil migration towards a chemotactic gradient of 10(-7) M fMLP. The spatial organization of occludin and VE-cadherin were also assessed in control and occludin peptide-treated monolayers by immunofluorescent staining. The cyclic peptide, peptide B, which contains the CAR sequence of occludin, increased neutrophil chemotaxis in a time and dose dependent manner. Scrambled sequence peptide controls and linear peptides did not. The cyclic occludin antagonist, peptide B, disorganized junctional occludin, but apparently not VE-cadherin as assessed by immunofluorescence. The correlation between diminished occludin organization and increased neutrophil trans-endothelial chemotaxis provides additional support for occludin in the maintenance of the tight junctional barrier. 相似文献
998.
Short-term effect of zidovudine on plasma and genital human immunodeficiency virus type 1 and viral turnover in these compartments
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Mbori-Ngacha D Richardson BA Overbaugh J Panteleeff DD Nduati R Steele M John-Stewart G 《Journal of virology》2003,77(13):7702-7705
The effect of zidovudine on plasma and genital human immunodeficiency virus type 1 (HIV-1) was determined in 42 antiretroviral-naive HIV-1-seropositive women in Nairobi. After 7 days of zidovudine treatment, HIV-1 RNA levels decreased by 0.5 to 1.1 log(10) in plasma and genital secretions. HIV-1 RNA half-life following zidovudine treatment was 4.7, 1.3, and 0.9 days in plasma, cervix, and vagina, respectively, and significantly shorter in genital secretions than in plasma (P < 0.001). Defining the short-term effect of zidovudine on plasma and genital HIV-1 is important for improving perinatal HIV-1 interventions. 相似文献
999.
Impairment of energy metabolism in hippocampus of rats subjected to chemically-induced hyperhomocysteinemia 总被引:5,自引:0,他引:5
Streck EL Matté C Vieira PS Calcagnotto T Wannmacher CM Wajner M Wyse AT 《Biochimica et biophysica acta》2003,1637(3):187-192
Homocystinuria is an inherited metabolic disease biochemically characterized by tissue accumulation of homocysteine (Hcy). Mental retardation, ischemia and other neurological features, whose mechanisms are still obscure are common symptoms in homocystinuric patients. In this work, we investigated the effect of Hcy administration in Wistar rats on some parameters of energy metabolism in the hippocampus, a cerebral structure directly involved with cognition. The parameters utilized were 14CO2 production, glucose uptake, lactate release and the activities of succinate dehydrogenase and cytochrome c oxidase (COX). Chronic hyperhomocysteinemia was induced by subcutaneous administration of Hcy twice a day from the 6th to the 28th day of life in doses previously determined in our laboratory. Control rats received saline in the same volumes. Rats were killed 12 h after the last injection. Results showed that Hcy administration significantly diminished 14CO2 production and glucose uptake, as well as succinate dehydrogenase and COX activities. It is suggested that impairment of brain energy metabolism may be related to the neurological symptoms present in homocystinuric patients. 相似文献
1000.