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91.
We describe a radial partition enzyme immunoassay in which fully automated quantification of human thyrotropin (hTSH) takes less than 11 min. This "sandwich"-type assay involves two monoclonal antibodies, both specific for the intact hTSH molecule. The solid phase consists of tabs of glass-fiber filter paper containing a pre-immobilized monoclonal anti-hTSH antibody complexed with a goat antibody specific for the Fc region of mouse IgG. The patient's sample is first applied to the central "reaction zone" of the tab, wherein hTSH binds to the immobilized antibody. Application of a buffered solution containing enzyme-labeled Fab' fragments of the second monoclonal anti-hTSH antibody initiates "sandwich" formation. A wash buffer containing a fluorogenic substrate elutes unbound conjugate to the tab periphery. The bound enzyme conjugate is quantified by measuring the rate of increase in fluorescence in the reaction zone of the tab, then converting the rate to clinical units by comparison with a stored calibration curve. The clinical utility and performance of the present assay compare favorably with those of other sensitive assays for hTSH. 相似文献
92.
Superior mesenteric artery is more important than inferior mesenteric artery in maintaining colonic mucosal perfusion and integrity in rats 总被引:1,自引:0,他引:1
Dr. Felix W. Leung MD Kenny C. Su MD Jose M. Pique MD Gerard Thiefin MD Edward Passaro Jr MD Paul H. Guth MD 《Digestive diseases and sciences》1992,37(9):1329-1335
Mucosal hemodynamics (by reflectance spectrophotometry) and mucosal damage (by histologic examination) following acute colonic ischemia were evaluated in different anatomic locations in the colon of anesthetized rats. The reflectance spectrophotometer provides an index of mucosal hemoglobin concentration (IHB) and an index of oxygen saturation of hemoglobin (ISO2). The patterns of ischemia without congestion (IHB, ISO2) during superior mesenteric artery occlusion, and ischemia with congestion (IHB, ISO2) during portal vein occlusion, previously demonstrated in the stomach and duodenum, are also applicable to the colon. The significant linear correlations between changes (as percent of baseline) in IHB, ISO2, and hydrogen gas clearance suggest that changes in these indices are adequate indicators of changes in colonic mucosal perfusion. Superior mesenteric artery ligation produced significant reductions in both indices, and an increase in damage in the mucosa of the cecum, transverse colon, splenic flexure, and left colon, but not the rectum. Inferior mesenteric artery ligation produced only slight reduction in these indices and minimal damage only in the mucosa of the splenic flexure. These results support the hypothesis that the superior mesenteric artery is more important than the inferior mesenteric artery in maintaining colonic perfusion and colonic mucosal integrity in the rat.Supported by the American Society for Gastrointestinal Endoscopy Career Development Award (H850208, H870212), Veterans Administration Medical Research Funds; and in part by research grants (0162-01, 0162-02; 0291-01) from the Smokeless Tobacco Research Council, Inc.; and by funds provided by the Cigarette and Tobacco Surtax Fund of the State of California through the Tobacco Related Disease Research Program of the University of California. 相似文献
93.
P C Leung 《Microsurgery》1989,10(3):242-244
This study reports the results of 30 patients who entered a program of sensory reeducation following toe-to-thumb transfer. Results were analyzed after subdividing the patients into those whose injury had produced severe scarring (fibrotic group, N = 15) and those with clean, more distal amputations (non-fibrotic group, N = 15). Patients who were unable to complete sensory reeducation were considered as "drop-out" controls. Although the follow-up time was less than 1 year, the group receiving sensory reeducation did improve to a greater degree and more quickly than the controls, with the level of two-point discrimination recovered being better than that originally present in the toe. 相似文献
94.
Knopik VS Sparrow EP Madden PA Bucholz KK Hudziak JJ Reich W Slutske WS Grant JD McLaughlin TL Todorov A Todd RD Heath AC 《Psychological medicine》2005,35(5):625-635
BACKGROUND: Genetic influences have been shown to play a major role in determining the risk of attention-deficit hyperactivity disorder (ADHD). In addition, prenatal exposure to nicotine and/or alcohol has also been suggested to increase risk of the disorder. Little attention, however, has been directed to investigating the roles of genetic transmission and prenatal exposure simultaneously. METHOD: Diagnostic telephone interview data from parents of Missouri adolescent female twin pairs born during 1975-1985 were analyzed. Logistic regression models were fitted to interview data from a total of 1936 twin pairs (1091 MZ and 845 DZ pairs) to determine the relative contributions of parental smoking and drinking behavior (both during and outside of pregnancy) as risk factors for DSM-IV ADHD. Structural equation models were fitted to determine the extent of residual genetic and environmental influences on ADHD risk while controlling for effects of prenatal and parental predictors on risk. RESULTS: ADHD was more likely to be diagnosed in girls whose mothers or fathers were alcohol dependent, whose mothers reported heavy alcohol use during pregnancy, and in those with low birth weight. Controlling for other risk factors, risk was not significantly increased in those whose mothers smoked during pregnancy. After allowing for effects of prenatal and childhood predictors, 86% of the residual variance in ADHD risk was attributable to genetic effects and 14% to non-shared environmental influences. CONCLUSIONS: Prenatal and parental risk factors may not be important mediators of influences on risk with much of the association between these variables and ADHD appearing to be indirect. 相似文献
95.
An efficient SNP system for mouse genome scanning and elucidating strain relationships 总被引:8,自引:0,他引:8
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Petkov PM Ding Y Cassell MA Zhang W Wagner G Sargent EE Asquith S Crew V Johnson KA Robinson P Scott VE Wiles MV 《Genome research》2004,14(9):1806-1811
A set of 1638 informative SNP markers easily assayed by the Amplifluor genotyping system were tested in 102 mouse strains, including the majority of the common and wild-derived inbred strains available from The Jackson Laboratory. Selected from publicly available databases, the markers are on average ~1.5 Mb apart and, whenever possible, represent the rare allele in at least two strains. Amplifluor assays were developed for each marker and performed on two independent DNA samples from each strain. The mean number of polymorphisms between strains was 608±136 SD. Several tests indicate that the markers provide an effective system for performing genome scans and quantitative trait loci analyses in all but the most closely related strains. Additionally, the markers revealed several subtle differences between closely related mouse strains, including the groups of several 129, BALB, C3H, C57, and DBA strains, and a group of wild-derived inbred strains representing several Mus musculus subspecies. Applying a neighbor-joining method to the data, we constructed a mouse strain family tree, which in most cases confirmed existing genealogies. 相似文献
96.
Glucocorticoid inhibition of antigen-evoked histamine release from human skin 总被引:1,自引:0,他引:1
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Prednisolone causes a dose-related inhibition of antigen-evoked histamine release from IgE-sensitized human skin in vitro. The effective concentrations are of the same order as are achieved in plasma therapeutically.
Analysis of prednisolone inhibition shows that it acts on the second histamine release stage, antigen—antibody combination being unaffected.
In contrast with the traditional view, our results show that, at least in human skin, glucocorticoids can inhibit antigen-evoked histamine release.
相似文献97.
Neuropathogenesis of Chimeric Simian/Human Immunodeficiency Virus infection In Pig-tailed and Rhesus Macaques 总被引:2,自引:0,他引:2
Ravi Raghavan Edward B Stephens Sanjay V Joag Istvan Adany David M Pinson Zhuang Li Fenglan Jia Manisha Sahni Chunyang Wang Kevin Leung Larry Foresman Opendra Narayan 《Brain pathology (Zurich, Switzerland)》1997,7(3):851-861
We recently reported that a chimeric simian/human immunodeficiency virus (SHIVKU-1 ) developed in our laboratory caused progressive depletion of CD4+ T lymphocytes and AIDS within 6 months of inoculation into pig-tailed macaques (M.nemestrina). None of the pig-tailed macaques showed productive SHIV infection in the central nervous system (CNS). In this report, we show that by further passage of the pathogenic virus in rhesus macaques [M. mulatta], we have derived a new strain of SHIV (SHIVKU-2 ) that has caused AIDS and productive CNS infection in 3 of 5 rhesus macaques infected with the virus. Productive replication of SHIV in the CNS was clearly shown by high infectivity titers and p27 protein levels in brain homogenates, and in 2 of the 3 rhesus macaques this was associated with disseminated, nodular, demyelinating lesions, including focal multinucleated giant cell reaction, largely confined to the white matter. These findings were reminiscent of HIV-1 associated neurological disease, and our immunohistochemical and in situ hybridization data indicated that the neuropathological lesions were associated with the presence of SHIV-specific viral antigens and nucleic acid respectively. However, the concomitant reactivation of opportunistic infections in these macaques suggested that such pathogens may have influenced the replication of SHIV in the CNS, or modified the neuropathological sequelae of SHIV infection in the rhesus species, but not in pig-tailed macaques. Our findings in the two species of macaques highlight the complexities of lentiviral neuropathogenesis, the precise mechanisms of which are still elusive. 相似文献
98.
A two-site sandwich immunoradiometric assay of human lymphotoxin with monoclonal antibodies and its applications 总被引:1,自引:0,他引:1
A Meager S Parti H Leung J Woolley E Peil S Sidhu T Roberts 《Journal of immunological methods》1987,104(1-2):31-42
Three monoclonal antibodies (MoAbs L49-15, L81-11 and L238-14) were raised against recombinant human lymphotoxin (rLT) derived from E. coli containing the cDNA sequence specifying LT. MoAb L81-11 strongly neutralised the cytotoxicity of LT derived either from E. coli or the RPMI 1788 lymphoblastoid cell line, whilst the other two MoAbs were only weakly neutralising in this respect. L81-11 and L238-14 MoAbs bound to different antigenic determinants on the rLT molecule, but neither bound to other lymphokines such as the structurally related tumour necrosis factor (TNF). As such, these MoAbs were ideal reagents for immunoassay of LT and a very sensitive, highly specific immunoradiometric assay (IRMA) was developed. This assay was rapid to perform and was capable of detecting as little as 10 pg/ml of LT. Application of the LT IRMA in combination with previously developed human gamma-interferon (IFN-gamma) and human TNF-specific IRMA (Crane et al., 1985; Meager et al., 1987) permitted independent estimations of these three substances to be carried out in parallel. By these means, it was found that RPMI 1788 produced both LT and TNF, but not IFN-gamma. Extensive analyses on cytokine (monokine and lymphokine) preparations derived from a variety of activated lymphocytes are also reported. Co-production of LT, TNF and IFN-gamma was a common finding, even occurring in alloantigen-specific T helper cell clones. 相似文献
99.
100.
IL-18 induces the differentiation of Th1 or Th2 cells depending upon cytokine milieu and genetic background 总被引:7,自引:0,他引:7
Xu D Trajkovic V Hunter D Leung BP Schulz K Gracie JA McInnes IB Liew FY 《European journal of immunology》2000,30(11):3147-3156
The functional division of CD4(+) T cells into Th1 and Th2 subsets is generally accepted but the mechanisms leading to their preferential induction remain elusive. Cytokines are considered the main determining factors in the initial differentiation of precursor T cells into these distinct subsets. Thus, IL-12 drives Th1 cells whereas IL-4 drives Th2 cells. Recently IL-18, originally designated as IFN-gamma-inducing factor, has been reported to synergize with IL-12 in the induction of Th1 cells. We report here that IL-18 can also induce T cells to differentiate into Th2 cells, in the presence of TCR activation, either alone or together with IL-4. This effect of IL-18 is mediated primarily on CD4(+) T cells compared with CD8(+) T cells and is inhibited in the presence of IL-12. IL-18, however, has no effect on functionally committed Th2 cells.( )Moreover, the effect of IL-18 on Th2 cell development is differentially manifest in different mouse strains, suggesting profound underlying genetic influences. BALB/c mice infected with Leishmania major and treated with recombinant IL-18 developed exacerbated disease and enhanced Th2 response compared with untreated controls. These data therefore provide a novel mechanism for Th2 cell development. Thus, IL-18, a cytokine constitutively expressed by cells of the innate response, is capable of inducing Th2 cell differentiation in the absence of IL-4. 相似文献