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11.
In vitro protein synthesis, lysosomal hydrolases activity and peroxidase activity in the anterior pituitary were estimated in adult male rats treated with 50 micrograms of estradiol benzoate (EB) for 1 day or 7 days. Pituitary protein synthesis, protein and RNA content increased after 7 days. A significant increase in total and membrane-bound acid phosphatase was noted after 1 day or 7 days of EB treatment whereas total beta-glucuronidase activity decreased in both 1 and 7 day group. Cathepsin activity increased after 7 days and pituitary peroxidase system did not change by EB treatment. These findings suggest that immediate change in the enzyme milieu may be one of the first reactions by which EB expresses its feedback control. 相似文献
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vif-negative human immunodeficiency virus type 1 persistently replicates in primary macrophages, producing attenuated progeny virus. 总被引:1,自引:1,他引:0 下载免费PDF全文
I H Chowdhury W Chao M J Potash P Sova H E Gendelman D J Volsky 《Journal of virology》1996,70(8):5336-5345
The vif gene of human immunodeficiency virus type 1 (HIV-1) is required for efficient infection of primary T lymphocytes. In this study, we investigated in detail the role of vif in productive infection of primary monocyte-derived macrophages (MDM). Viruses carrying missense or deletion mutations in vif were constructed on the background of the monocytotropic recombinant NLHXADA-GP. Using MDM from multiple donors, we found that vif mutants produced in complementing or partially complementing cell lines were approximately 10% as infectious as wild-type virus when assayed for incomplete, complete, and circularized viral DNA molecules by quantitative PCR amplification or for viral core antigen p24 production by enzyme-linked immunosorbent assay. We then determined the structure and infectivity of vif mutant HIV-1 by using MDM exclusively both for virus production and as targets for infection. Biosynthetic labeling and immunoprecipitation analysis of sucrose cushion-purified vif-negative HIV-1 made in MDM revealed that the virus had reduced p24 content compared with wild-type HIV-1. Cell-free MDM-derived vif mutant HIV-1 was infectious in macrophages as determined by the synthesis and maintenance of full-length viral DNA and by the produc- tion of particle-associated viral RNA, but its infectivity was approximately 2,500-fold lower than that of wild-type virus whose titer was determined in parallel by measurement of the viral DNA burden. MDM infected with MDM-derived vif-negative HIV-1 were able to transmit the virus to uninfected MDM by cocultivation, confirming the infectiousness of this virus. We conclude that mutations in vif significantly reduce but do not eliminate the capacity of HIV-1 to replicate and produce infectious progeny virus in primary human macrophages. 相似文献
14.
Ibuprofen, a unique anti-inflammatory compound with antifungal activity against dermatophytes 总被引:2,自引:2,他引:0
Ibuprofen showed significant antifungal activity in vitro against dermatophytes at pH 5 (MIC: 5–40 μg ml-1 ). In this respect it is comparatively more efficient than two well known and medically used antifungal compounds, benzoic and salicylic acids. This compound with anti-inflammatory activity which is not found in any other conventional antifungal organic acids, may have clinical prospects. 相似文献
15.
Microbial mineralization of organic phosphate in soil 总被引:35,自引:0,他引:35
Summary Phosphate-dissolving microorganisms were isolated from non-rhizosphere and rhizosphere of plants. These isolates included
bacteria, fungi and actinomycetes. In broth cultures, Gram-negative short rod,Bacillus andStreptomyces species were found to be more active in solubilizing phosphate thanAspergillus, Penicillium, Proteus, Serratia, Pseudomonas andMicrococcus spp. The sterile soils mixed with isolated pure culture showed slower mineralization of organic phosphate than that of non-sterile
soil samples at all incubation periods. Maximum amount of phosphate mineralization by isolated microorganisms were obtained
at the 60th and the 75th day of incubation in sterile and non-sterile soils respectively. The mixed cultures were most effective
in mineralizing organic phosphate and individuallyBacillus sp. could be ranked next to mixed cultures. Species ofPseudomonas andMicrococcus were almost the same as that of the control under both sterile and non-sterile conditions. 相似文献
16.
P L Jansen J R Chowdhury E B Fischberg I M Arias 《The Journal of biological chemistry》1977,252(8):2710-2716
Formation of bilirubin monoglucuronide from unconjugated bilirubin requires a microsomal enzyme, UDP-glucuronate glucuronyltransferase (EC 2.4.1.17). Conversion of bilirubin monoglucuronide to bilirubin diglucuronide, the major bilirubin conjugate in bile, was studied in subcellular fractions of rat liver. The highest specific activity for bilirubin diglucuronide formation occurred in a fraction highly enriched in plasma membranes. Studies of reaction stoichiometry and utilization of UDP-D-[14C]glucuronic acid revealed that conversion of bilirubin monoglucuronide to bilirubin diglucuronide is not catalyzed by UDP-glucuronyltransferase, and results from transglucuronidation of bilirubin monoglucuronide, with formation of bilirubin diglucuronide and unconjugated bilirubin. When unconjugated bilirubin was infused intravenously into rats at rates exceeding the maximal hepatic excretory capacity, bilirubin monoglucuronide accumulated in serum and bilirubin diglucuronide was found exclusively in bile as the predominant bilirubin metabolite. These results suggest that formation of bilirubin diglucuronide occurs at the surface membrane of the liver cell. Conversion of bilirubin monoglucuronide to bilirubin diglucuronide may play a role in the transport of bilirubin glucuronides from liver to bile. 相似文献
17.
In order to assess the impact of nutritional status on the onset of menarche and the association between age at menarche and age at marriage, a survey of 1155 girls, ages 10 through 20, was conducted in a rural area of Bangladesh in March 1976. In order to obtain an estimated mean of age of menarche, probit analysis was used. The mean age of menarche using this technique is estimated at 15.65 for Muslims and 15.91 for Hindus. It was learned that in recent years the age of menarche has increased in a rural area. This increase seems to be associated with malnutrition caused by the war, postwar inflation, floods and famines during the 1971-75 period. When age is controlled for, the prominent effect of weight on menstrual status is evident. 98% of the girls whose weights were 88 pounds or greater had reached menarche compared to only 1% of those weighing less than 66 pounds. Body weight appears to be 1 of the most important factors for the determination of onset of menarche. There exists a seasonality of onset of menarche with a peak in winter. Age of marriage among this rural population has increased and may be associated with the increasing age of menarche. Since both age of menarche and age of marriage have increased, fertility among females age 15-19 may be expected to decrease in the future if this pattern continues. 相似文献
18.
The aim of the present investigation is to evaluate adrenomedullary hormones and blood glucose responses to intermale aggression in the bandicoot rat. Aggression elicited a rise in adrenaline and noradrenaline content of the adrenal gland and in blood glucose level in the subordinate rats. No significant change was marked in the dominant rats after aggression. It is suggested that during aggression the subordinate rats suffered from psychosomatic stress that resulted in hyperactivity of the adrenal medulla and consequently hyperglycemia. 相似文献
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20.
A 14-kilodalton inner membrane protein of Vibrio cholerae biotype e1 tor confers resistance to group IV choleraphage infection to classical vibrios. 下载免费PDF全文
Choleraphage phi 149 differentiates the two biotypes, classical and el tor, of Vibrio cholerae. This phage cannot replicate in V. cholerae biotype el tor cells because the concatemeric DNA intermediates produced are unstable and cannot be chased to mature phage DNA. A V. cholerae biotype el tor gene coding for a 14,000-Da inner membrane protein which destabilizes the concatemeric DNA intermediates by hindering their binding to the cell membrane has been identified. Presumably, a 22,000-Da V. cholerae biotype el tor protein might also have a role in conferring phage phi 149 resistance to cells belonging to the biotype el tor. A nucleotide sequence homologous to the 1.2-kb V. cholerae biotype el tor DNA coding for both the 14,000- and 22,000-Da proteins is present in all strains of classical vibrios but is not transcribed. The nucleotide sequence of the gene coding for the 14,000-Da protein has been determined. 相似文献