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991.
The experiments described here were conducted to examine regulation of cytochrome P-450 side-chain cleavage (SCC) mRNA accumulation in porcine granulosa cells isolated from small (1-4-mm) and medium (5-6-mm) follicles. Granulosa cells were cultured under the following conditions: 1) for 48 h or 96 h with 0, 50, or 200 ng/ml porcine FSH; 2) for 96 h with 200 ng/ml FSH and aminoglutethimide (100 microM); and 3) for 96 h with forskolin (100 microM). Total RNA was extracted and examined by Northern and dot-blot hybridization analysis, and culture media were assayed for progesterone concentration. Northern blot analysis revealed a single band approximately 2.1 kb in size. Accumulation of SCC mRNA by granulosa cells was both FSH dose- and culture time-dependent (p less than 0.05) with maximal increases approximately 4.5 times control levels. Aminoglutethimide reduced progesterone production by about 80% while having no effect on granulosa cell accumulation of SCC mRNA compared to cells stimulated with 200 ng/ml of FSH. Forskolin-treated cells produced significantly more progesterone than did cells treated with FSH, but accumulation of SCC mRNA was similar. In response to FSH, concentration of SCC mRNA did not vary with follicle size, but granulosa cells from small follicles produced significantly more progesterone than did those from medium follicles. These results demonstrate that concentration of SCC mRNA in cultured porcine granulosa cells is FSH dose-dependent, does not vary significantly in cells from small- and medium-sized follicles, and is correlated with progesterone production, but may not parallel progesterone secretion. This last observation indicates that control at sites other than SCC mRNA can affect progesterone production. 相似文献
992.
A detailed multipoint map of human chromosome 4 provides evidence for linkage heterogeneity and position-specific recombination rates 总被引:5,自引:3,他引:2 下载免费PDF全文
Kenneth H. Buetow Rita Shiang Ping Yang Yusuke Nakamura G. Mark Lathrop Raymond White John J. Wasmuth Stephen Wood Laura D. Berdahl Nancy J. Leysens Timothy M. Ritty Molly E. Wise Jeffrey C. Murray 《American journal of human genetics》1991,48(5):911-925
Utilizing the CEPH reference panel and genotypic data for 53 markers, we have constructed a 20-locus multipoint genetic map of human chromosome 4. New RFLPs are reported for four loci. The map integrates a high-resolution genetic map of 4p16 into a continuous map extending to 4q31 and an unlinked cluster of three loci at 4q35. The 20 linked markers form a continuous linkage group of 152 cM in males and 202 cM in females. Likely genetic locations are provided for 25 polymorphic anonymous sequences and 28 gene-specific RFLPs. The map was constructed employing the LINKAGE and CRIMAP computational methodologies to build the multipoint map via a stepwise algorithm. A detailed 10-point map of the 4p16 region constructed from the CEPH panel provides evidence for heterogeneity in the linkage maps constructed from families segregating for Huntington disease (HD). It additionally provides evidence for position-specific recombination frequencies in the telomeric region of 4p. 相似文献
993.
At present, there is a renewed interest in thymic function and its secretions in relation to endocrine control and reproductive function. In an initial experiment, 60 crossbred heifers (18-20 mo) were detected in estrus and assigned to control or FSH superovulatory groups. On Days 7-14 of the subsequent estrous cycle, FSH was administered for 5 days and prostaglandin F2 alpha (PGF2 alpha) was administered at 48 and 60 h after the initial FSH injection. Control animals received only PGF2 alpha injections between Days 9 and 15 of the cycle. Blood samples were collected from all animals at the time of PGF2 alpha injection and every 12 h thereafter to 72 h post PGF2 alpha injection. In a subsequent experiment, 103 crossbred heifers (16-18 mo) were superovulated with FSH and synchronized to estrus with PGF2 alpha administered 60 h after the initial FSH injection. Twenty-eight of the heifers received Norgestomet implants 12 h prior to the initial PGF2 alpha injection to inhibit the LH surge. Blood samples were collected from animals at 12-h intervals until the PGF2 alpha injection and every 6 h thereafter until 108 h post PGF2 alpha treatment. Although thymosin beta 4 concentrations did change over the estrual period, no differences were noted between control and superovulatory animals in the initial experiment even though estradiol concentrations were increased tenfold from the FSH stimulated ovary. In the second experiment, thymosin beta 4 and alpha 1 increased as the estrual period progressed and decreased (p less than 0.05) subsequent to the LH surge. (ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
994.
Transfer of silver-stained proteins from polyacrylamide gels to polyvinylidene difluoride membranes.
We have developed a method to transfer proteins from a silver-stained polyacrylamide gel to a polyvinylidene difluoride (Immobilon-P) transfer membrane (Millipore, Bedford, MA). If the silver stained gels are rinsed in 2 x SDS Laemmli sample buffer prior to transfer, almost all proteins can be transferred comparably to non-stained controls. Some proteins stained with silver can be directly transfer, almost all proteins can be transferred comparably to non-stained controls. Some proteins stained with silver can be directly transferred to a single sheet of Immobilon-P without a prior rinse in sample buffer. Most important in the Western blot the antigenicity of the transferred protein is retained in either way. The method described is simple, inexpensive and versatile. A slight modification of the technique permits one to extract minor proteins, or detect their antigenic activities, without contamination of contiguous proteins. 相似文献
995.
996.
Elimination of the immunogenicity of therapeutic antibodies 总被引:4,自引:0,他引:4
Gilliland LK Walsh LA Frewin MR Wise MP Tone M Hale G Kioussis D Waldmann H 《Journal of immunology (Baltimore, Md. : 1950)》1999,162(6):3663-3671
The immunogenicity of therapeutic Abs limits their long-term use. The processes of complementarity-determining region grafting, resurfacing, and hyperchimerization diminish mAb immunogenicity by reducing the number of foreign residues. However, this does not prevent anti-idiotypic and anti-allotypic responses following repeated administration of cell-binding Abs. Classical studies have demonstrated that monomeric human IgG is profoundly tolerogenic in a number of species. If cell-binding Abs could be converted into monomeric non-cell-binding tolerogens, then it should be possible to pretolerize patients to the therapeutic cell-binding form. We demonstrate that non-cell-binding minimal mutants of the anti-CD52 Ab CAMPATH-1H lose immunogenicity and can tolerize to the "wild-type" Ab in CD52-expressing transgenic mice. This finding could have utility in the long-term administration of therapeutic proteins to humans. 相似文献
997.
Wise DM 《Plastic and reconstructive surgery》1999,104(2):491-494
A patient with the rare genetic disease of mitochondrial oxidative phosphorylation is presented. The phenotypic presentation included localized, idiosyncratic lipodystrophy that caused life-threatening respiratory obstruction. Plastic surgical excision and suction-assisted lipoplasty of huge deposits of fat and skin led to marked improvement in patient posture and ventilation. This rare disorder, stages of treatment, and salient references are discussed. 相似文献
998.
Hammons GJ Yan Y Lopatina NG Jin B Wise C Blann EB Poirier LA Kadlubar FF Lyn-Cook BD 《Cell biology and toxicology》1999,15(6):389-394
The DNA methyltransferase enzyme (DNA MTase) catalyzes DNA methylation at cytosines in CpG dinucleotides. 5-Methylcytosine
modification of DNA is important in gene regulation, DNA replication, chromatin organization and disease. Increased levels
of DNA MTase have been associated with the initiation and promotion of cancer. This study was conducted to assess whether
cigarette smoking and other factors, such as age and gender, influence DNA MTase expression in nontumorous tissue. DNA MTase
was significantly (p<0.05) higher in samples from cigarette smokers; the mean level of DNA MTase mRNA was almost 2-fold higher in these samples
than in those from nonsmokers. Levels of DNA MTase mRNA were higher in samples from females than in those from males, but
the difference was not statistically significant. Age was not associated with DNA MTase levels. Increased levels of DNA MTase
in individuals who smoke may indicate a greater susceptibility to the risk of cancer since increased levels of this enzyme
are found in cancer cell lines and human tumors. The results of this study suggest that further investigations of increased
expression of this enzyme as a predisposing factor for cancer susceptibility are needed.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
999.
This special issue of the Journal of Neurocytology focuses on the cellular and molecular mechanisms of neuroprotection by steroid hormones. Clinical and basic science studies have led to a deeper understanding of these novel and non-reproductive actions of steroids. New findings on neuroprotective effects of steroids in the peripheral and central nervous system and the discovery of new molecular targets and new signaling pathways of steroids has expanded, and at the same time complicated, the search for the mechanisms involved in the neuroprotection by these molecules. We considered that now is an ideal time to bring together the different views, experimental models and methodological approaches that constitute this emerging field. 相似文献
1000.
Abstract: Bioassays were conducted to compare the residual toxicity and leaf protection activity of conventional broad-spectrum and reduced-risk insecticides against the rose chafer, Macrodactylus subspinosus . Insecticides were applied to a Vitis labrusca (F.) vineyard and residues were aged for 1, 3 or 7 days before leaves were collected and exposed to beetles in no-choice tests. Azinphosmethyl caused rapid knockdown and mortality for up to 1 week after application, with 1-day-old residues providing 95.6% protection against feeding, dropping to 51.6% when residues were a week old. Fenpropathrin caused mortality and knockdown after beetles had been exposed to fresh residues for 72 h. Although these effects diminished as residues aged, this compound provided the best protection of leaves against beetle feeding, with 77.9% reduction in feeding compared with the control after 7 days of aging in the vineyard. Of the reduced-risk insecticides, imidacloprid caused the greatest initial mortality and knockdown of beetles, providing protection against feeding that was equivalent to azinphosmethyl. Exposure to azadirachtin caused a low level of knockdown and mortality when residues were 1- and 3-days old. Protection against feeding was also low, lasting for only 3 days. Beetles were minimally affected by capsaicin and kaolin, with mortality and knockdown seen only when beetles were exposed to 1-day-old residues for 72 h. Foliage protection from these compounds was minimal, with between 10 and 15% reduction in feeding injury. Results are discussed in relation to development of semi-field bioassay methods for evaluating reduced-risk insecticides, and the management of M. subspinosus within grape pest management programs. 相似文献