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91.
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The liver is a target for toxic chemicals such as cadmium (Cd). When the liver is damaged, hepatic stellate cells (HSC) are activated and transformed into myofibroblast-like cells, which are responsible for liver fibrosis. Curcuma longa has been reported to exert a hepato-protective effect under various pathological conditions. We investigated the effects of C. longa administration on HSC activation in response to Cd induced hepatotoxicity. Forty adult male albino rats were divided into: group 1 (control), group 2 (Cd treated), group 3 (C. longa treated) and group 4 (Cd and C. longa treated). After 6 weeks, liver specimens were prepared for light and electron microscopy examination of histological changes and immunohistochemical localization of alpha smooth muscle actin (αSMA) as a specific marker for activated HSC. Activated HSC with a positive αSMA immune reaction were not detected in groups 1 and 3. Large numbers of activated HSC with αSMA immune reactions were observed in group 2 in addition to Cd induced hepatotoxic changes including excess collagen deposition in thickened portal triads, interlobular septa with hepatic lobulation, inflammatory cell infiltration, a significant increase in Kupffer cells and degenerated hepatocytes. In group 4, we observed a significant decrease in HSC that expressed αSMA with amelioration of the hepatotoxic changes. C. longa administration decreased HSC activation and ameliorated hepatotoxic changes caused by Cd in adult rats. 相似文献
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The plant alkaloids vinblastine and colchicine are known to arrest cells in mitosis by virtue of their binding to spindle protein. These drugs are also capable of binding to microtubule protein and causing these structures to disaggregate into nonfunctional subunits (1, 2). Microtubular structures are thought to be involved in the secretory process of a number of proteins including insulin (7), collagen (4), and thyroid hormone (12). In this report we present our findings on the effects of these two drugs on the synthesis and secretion of interferon in a high producing human foreskin fibroblast strain (FS-4) (11). 相似文献
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The Regulation of Synthesis and Storage of Chymotrypsin Inhibitor I in Leaves of Potato and Tomato Plants 总被引:2,自引:1,他引:1
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The synthesis and accumulation of chymotrypsin inhibitor I in tomato leaflets is induced by detachment, or by destruction of petiole phloem by steam when followed by incubation of the leaflets in light. The induction process with detached tomato leaflets is similar to that found with detached potato leaflets. The large amount of inhibitor I synthesized per leaflet cell per unit time suggests either that the structural gene is redundant or that an unusually stable messenger RNA is present. In both tomato and potato leaflets the accumulation of inhibitor I is potently inhibited by actinomycin D, puromycin, and cycloheximide, but not by chloramphenicol. Indoleacetic acid is moderately inhibitory, as is 3-(3,4-dichlorophenyl)-1,1-dimethylurea. Glutamine and asparagine are both markedly stimulating. The cumulative data suggest that inhibitor I is a major depot or interim storage protein and that its existence in any particular tissue is under complex controls by both the internal and external environments of the plants. 相似文献
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- 1.
- 1. Structural and quantitative studies have been made on hemoglobins of Virginia white-tailed deer, Odocoilus virginianus, with emphasis on the α chains. Hemoglobins with Iα chains have been termed “major” and those with IIα chains “minor.” Previous studies of over 400 deer have shown that all animals produce major components, but many do not have the minor components. These observations as well as data showing that the minor component can be present in 15% or 30% proportions have been considered to indicate the presence of two nonallelic Hbα structural loci. 相似文献
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Summary Detailed restriction enzyme analysis of the DNA from a Chinese female showed that one of her chromosomes had a >17.5 kb deletion of DNA, including the , 2, and 1 globin genes, which is present in many Southeast Asians with an -thalassemia-1 chromosome. Her normal chromosome had the expected cluster of -like globin genes (5----2-1-3), but the segment of DNA between the two globin genes was elongated by some 0.5–0.7 kb. Analyses of various restriction sites suggested that this normal variant of the human globin gene complex is due to a crossover between a normal chromosome with () and a chromosome with an -thalassemia-2 (–3.7) and an -21-hybrid gene. 相似文献
100.
Different ζ globin gene deletions among Black Americans 总被引:7,自引:0,他引:7
A. E. Felice M. P. Cleek E. M. Marino K. M. McKie V. C. McKie B. K. Chang T. H. J. Huisman 《Human genetics》1986,73(3):221-224
Summary Four types of chromosomes with a deletion between the human embryonic and globin genes were identified among 2.8% of 321 Black Americans from Georgia. Two deletions of approximately 11 kb which differed by about 300 bp occurred on chromosomes with or without a polymorphic Xba I site 5 to the globin gene [(X+) or (X-)]. The deletions are identifiable in Xba I digests of genomic DNA using an or a globin gene probe which yield fragments of 23 kb from (X+)–* chromosomes or 27 kb from (X–)–* chromosomes. Digestion with other enzymes and probing with both and probes gave fragments typical of the two globin gene deletions previously identified in Polynesians. Among Black Americans, these globin gene deletions have been found in combination with globin gene deletions in trans but not in cis. Homozygotes have not been found. Hematologic data on carriers of the globin gene deletions in association with Hb AS, SS, and SC suggest that these deletions have no effect on the function of the adult globin genes. 相似文献