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101.
Strains of Mycobacterium terrae complex which react with DNA probes for M. tuberculosis complex. 总被引:1,自引:3,他引:1
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Following a recent report that two isolates of Mycobacterium terrae complex had given positive reactions with M. tuberculosis complex DNA probes, a joint study was undertaken to determine the extent of these findings in the clinical culture collection holdings of two state health laboratories. A total of 117 M. terrae complex strains (identified by standard biochemical methods) were subjected to M. tuberculosis complex probe testing with the two then-available kits (from Syngene, Inc., and Gen-Probe, Inc.). In addition to the two original isolates first reported, two further M. terrae complex isolates were found to react with the M. tuberculosis complex probes. Two modifications of the Accuprobe (Gen-Probe, Inc.) test method were evaluated. Extension of the selection time to 8 min was the most convenient modification and rendered the M. terrae complex isolates negative when tested with the Accuprobe M. tuberculosis complex probe. However, the effects of increased selection time on the overall sensitivity of the M. tuberculosis complex probe require further study. 相似文献
102.
Mycobacterium avium complex pseudobacteriuria from a hospital water supply. 总被引:2,自引:2,他引:2
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From July 1983 through November 1985, organisms belonging to Mycobacterium avium complex were isolated from the urine of 29 patients. Strains recovered from the urine of nine patients from July 1983 through August 1984 were serotyped. Eight of the nine samples belonged to serovar 4. M. avium complex was isolated from the urine of 21 patients during the period from November 1984 through November 1985. While the possibility of a point source contamination was investigated, M. avium complex was recovered from the phenol red solution used for processing urine specimens in the mycobacteriology laboratory and the deionized tap water of that laboratory that is used to make the reagent. M. avium complex serovar 4 was subsequently recovered from the tap water of the laboratory and four hospital wards. During the year following the installation of a microbiological filter for the mycobacteriology laboratory deionized tap water, 2 urine isolates were recovered, compared to 26 the previous year. This study demonstrates the importance of filtration devices at tap water sites that are used to make laboratory reagents and the value of serotyping as a marker for the detection of a specific source of M. avium complex contamination. 相似文献
103.
L J Yonk R P Warren R A Burger P Cole J D Odell W L Warren E White V K Singh 《Immunology letters》1990,25(4):341-345
CD4+ (helper) T cells are a heterogenous population of lymphocytes including at least two distinct subpopulations. To investigate the possibility that immune abnormalities in some subjects with autism may involve abnormal distributions of CD4+ and/or CD8+ cells, (suppressor) T cells, peripheral blood lymphocytes of 25 autistic subjects were characterized with monoclonal antibodies and flow cytometry. The autistic subjects had a significantly lower percentage and number of CD4+ cells, a lower number of T cells (CD2+ cells) and B cells (CD20+ cells), and a lower percentage and number of total lymphocytes than siblings and normal subjects. The level of blood values for female subjects appeared lower than those for males as compared to normal subjects of the same sex. These results suggest that a decrease in CD4+ cells is associated with autism. 相似文献
104.
105.
Dongari-Bagtzoglou AI; Warren WD; Berton MT; Ebersole JL 《International immunology》1997,9(9):1233-1241
CD40, a member of the tumor necrosis factor-alpha receptor family, is
constitutively expressed by cells of hematopoietic and non- hematopoietic
origin, including fibroblasts. Signaling through this receptor molecule
regulates inflammatory cytokine secretion by many cell types. Based on the
recently described cytokine secretory heterogeneity of fibroblast cell
subsets, we hypothesized that secretion of inflammatory cytokines by
gingival fibroblast cultures may be dictated by the existence of
differential proportions of cytokine- secreting subpopulations which
express high levels of CD40. After examining a large number of gingival
fibroblast (GF) cultures we find that the frequency of IL-6- and
IL-8-secreting cells mirrors the frequency of cells expressing high levels
of CD40 in these cultures. In addition, we demonstrate a direct functional
relationship between CD40 expression and IL-6 or IL-8 secretion by showing
that ligation of this molecule on GF, and CD40+ fibroblast subsets in
particular, up- regulates secretion of these cytokines in vitro.
相似文献
106.
107.
Receptor types in cat hairy skin supplied by myelinated fibers 总被引:9,自引:0,他引:9
108.
Bottini N MacMurray J Peters W Rostamkhani M Comings DE 《Molecular genetics and metabolism》2002,77(3):226-229
The acid phosphatase (ACP1) locus codes for a low molecular weight protein tyrosine phosphatase (LMPTP) that is found ubiquitously in human tissues. The *A allele of the ACP1 gene is associated with lower total enzymatic activity than the *B and *C alleles. An association between the *A allele and extreme values of body-mass-index (BMI) and dyslipidemia has previously been described in several samples of obese subjects from the Italian population. In the present study, we investigated the relationship between ACP1 *A allele genotypes (*A/*A, *A/*B, and *A/*C) and non-*A allele genotypes (*B/*B, *B/*C, and *C/*C) and metabolic variables in 277 Caucasian post-menopausal subjects consisting of 82 non-obese subjects (BMI=29), 60 moderately obese (BMI 30-34) and 135 very obese (BMI>/=35) subjects. ACP1 genotypes were found to be significantly associated with total cholesterol (p=0.002) and triglyceride (p=0.001) levels in the obese and very obese women only. The significantly lower levels of triglycerides in *A carriers in this group suggest a protective effect of the *A allele against hypertriglyceridemia. It has been unclear why some individuals who gain weight develop dyslipidemia and other aspects of the metabolic syndrome while others do not. The present study suggests that those who gain weight and carry the ACP1 *A allele may be partially protected against developing the metabolic syndrome. The confirmation of ACP1 as a modifier gene of the metabolic complications could open the door to the prevention of the lethal complications of obesity. 相似文献
109.
How is human locomotion visually controlled? Fifty years ago, it was proposed that we steer to a goal using optic flow, the pattern of motion at the eye that specifies the direction of locomotion. However, we might also simply walk in the perceived direction of a goal. These two hypotheses normally predict the same behavior, but we tested them in an immersive virtual environment by displacing the optic flow from the direction of walking, violating the laws of optics. We found that people walked in the visual direction of a lone target, but increasingly relied on optic flow as it was added to the display. The visual control law for steering toward a goal is a linear combination of these two variables weighted by the magnitude of flow, thereby allowing humans to have robust locomotor control under varying environmental conditions. 相似文献
110.