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1.
D A Nickson M W McBride S Zeinali C S Hawes A Petropoulos U W Mueller R G Sutcliffe 《Journal of reproduction and fertility》1991,93(1):149-156
The monoclonal antibody FDO161G reacts with a 43-kDa protein found in human extravillous trophoblast, syncytiotrophoblast, adrenal cortex, interstitial cells of the testis and ovarian follicle cumulus cells. cDNAs for this protein have been isolated from the lambda gt11 library, sequenced, and expressed in COS-7 cells. The protein was identified as 3 beta-hydroxy-5-ene steroid dehydrogenase (HSD). The sequence of the HSD protein raises questions about its association with cell membrane systems. The lack of reactivity of FDO161G with other tissues suggests that HSD has a limited tissue distribution and that other enzymes may exist in peripheral tissues, which can convert delta 5 3-hydroxysteroids to delta 4 3-ketosteroids. 相似文献
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Blood glucose and glucose tolerance tests demonstrated that many male MM mice are diabetic. Serial urine sampling showed that the diabetes occurred only in mature MM males and consisted of a single self-limiting episode. Histological examination of the pancreas, together with measurements of body weight, glycosylated haemoglobin and plasma insulin, revealed that the diabetes was of the maturity-onset insulin-resistant type. Bacteriological examination of the urine samples showed that urinary tract infection, a known feature of male MM mice, occurred in the diabetics but only after the onset of hyperglucosuria. It was concluded that the high urinary glucose levels of diabetic MM males are of prime importance in the aetiology of the renal infection which occurs rarely in non-diabetic MM males or in other strains in the colony. An infectious aetiology for the diabetes per se was excluded by the existence of diabetes in germfree MM males. 相似文献
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Analysis of the interaction of antibodies with immunoglobulin idiotypes on neoplastic B lymphocytes: implications for immunotherapy 总被引:5,自引:0,他引:5
T J Elliott M J Glennie H M McBride G T Stevenson 《Journal of immunology (Baltimore, Md. : 1950)》1987,138(3):981-988
We have examined the reactions of a panel of nine monoclonal anti-idiotype antibodies with the surface immunoglobulin in situ on guinea pig L2C leukemic lymphocytes. Equilibrium binding constants were shown to range between 10(7) and 10(8) M-1 for univalent Fab' gamma fragments and between 10(8) and 10(9) M-1 for intact IgG. Saturation of the cell surface binding sites was achieved with 2.9 X 10(5) Fab' gamma molecules/cell and 1.2 X 10(5) IgG molecules/cell for each antibody, a result that is consistent with a bivalent mode of interaction for the IgG. Despite these overall similarities in binding characteristics antibodies showed striking differences in their ability to clear Ig from the cell surface by antigenic modulation in vitro. This suggested differences in the readiness with which the antibodies cross-linked neighboring surface Ig molecules. Such an interpretation was supported by differences in the times required to achieve bivalent binding at 0 degree C, and in the rates at which labeled antibody dissociated from the cell surface in the presence or absence of an excess of unlabeled antibody. The data are consistent with there being two functionally distinct types of anti-idiotype antibody: those that form predominantly intra-Ig bridges, with each antibody Fab being linked to an Fab on one target molecule ("monogamous" binding) and not favoring modulation; and those that form predominantly inter-Ig bridges ("bigamous" binding) and favor modulation. The nature of interaction is presumably dictated by the orientation of the particular idiotope concerned. This distinction could be of great importance in the therapeutic use of anti-idiotype to ablate B cell neoplasms. 相似文献
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In pathogen-free mice, but not standard conventionally housed laboratory rodents, two distinctly different modes of early radiation lethality can be identified by modifying the irradiation technique (total-body versus abdominal irradiation) or by therapeutic intervention such as rescue of total-body-irradiated mice with syngeneic bone marrow or spleen. While damage to the gastrointestinal tract is usually designated as the predominant cause of death occurring within 10 days of radiation exposure, it was demonstrated that damage to the hematopoietic/lymphopoietic system can result in animal lethality over the same period as the gastrointestinal syndrome and that this target cell population is more radiation-sensitive than the gastrointestinal epithelium. 相似文献
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Human debrisoquine 4-hydroxylase (P450IID1): cDNA and deduced amino acid sequence and assignment of the CYP2D locus to chromosome 22 总被引:9,自引:0,他引:9
F J Gonzalez F Vilbois J P Hardwick O W McBride D W Nebert H V Gelboin U A Meyer 《Genomics》1988,2(2):174-179
The enzyme P450db1 (db1) is responsible for the common human defect in drug oxidation known as the "debrisoquine/sparteine polymorphism." Polyclonal antibody against the rat db1 protein was used to screen a human liver lambda gt11 library for the db1 cDNA clone. A cDNA containing the full protein coding sequence was isolated; the deduced NH2-terminal sequence of this cDNA was identical to that derived from direct sequencing of the purified human db1 protein. Comparison of the human db1 with rat db1 revealed 71 and 73% similarities of nucleotides and amino acids, respectively. By use of human-rodent somatic cell hybrids the db1 gene was localized to human chromosome 22 (CYP2D locus). 相似文献
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Application of automated DNA sizing technology for genotyping microsatellite loci. 总被引:21,自引:0,他引:21
J S Ziegle Y Su K P Corcoran L Nie P E Mayrand L B Hoff L J McBride M N Kronick S R Diehl 《Genomics》1992,14(4):1026-1031
Highly polymorphic microsatellite loci offer great promise for gene mapping studies, but fulfillment of this potential will require substantial improvements in methods for accurate and efficient genotyping. Here, we report a genotyping method based on fluorescently labeled PCR primers and size characterization of PCR products using an automated DNA fragment analyzer. We capitalize on the availability of three distinct fluorescent dyes to label uniquely loci that overlap in size, and this innovation increases by threefold the number of loci that can be analyzed simultaneously. We label size standards with a fourth dye and combine these with the microsatellite PCR products in each gel lane. Computer programs provide very rapid and accurate sizing of microsatellite alleles and efficient data management. In addition, fluorescence signals are linear over a much greater range of intensity than conventional autoradiography. This facilitates multiplexing of loci (since signal intensities often vary greatly) and helps distinguish major peaks from artifacts, thereby improving genotyping accuracy. 相似文献
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