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41.
M. A. Read 《The American journal of pathology》1995,147(2):235-237
42.
Clinical implications of positive tests for antibodies to human immunodeficiency virus type 1 in asymptomatic blood donors 总被引:4,自引:0,他引:4
S F Leitman H G Klein J J Melpolder E J Read J I Esteban E M Leonard L Harvath J W Shih R Nealon J Foy 《The New England journal of medicine》1989,321(14):917-924
Of 693,000 volunteer blood donors in Washington, D.C., who were screened for infection with human immunodeficiency virus type 1 (HIV-1) from July 1985 through December 1988, 284 tested positive on both enzyme immunoassay and Western blot assay. To determine the clinical importance of confirmed positive test results in asymptomatic blood donors, we followed 156 donors with positive Western blot assays and 80 donors with positive enzyme immunoassays but negative or indeterminate Western blots at 6-month intervals for a mean of 28 months. As compared with Western blot-negative persons, those with positive Western blots were significantly more likely to be black, male, and first-time donors and to have a history of venereal disease, generalized lymphadenopathy on examination, CD4-cell counts lower than 0.4 x 10(9) per liter, IgG levels higher than 18 g per liter, and antibody to hepatitis B core antigen on initial evaluation. In 17 (11 percent) of the Western blot-positive donors, the disease progressed to Class IV (symptomatic disease), according to the Centers for Disease Control system. CD4 counts below 0.2 x 10(9) per liter, IgA levels above 4 g per liter, abnormal proliferative responses to tetanus toxoid, and positive viral cultures were the strongest predictors of disease progression. Among the 80 donors with repeatedly reactive assay results but either negative or indeterminate Western blot assays, there was no evidence of HIV exposure in their histories, physical examinations, or laboratory evaluations, and manifestations of HIV infection developed in none of them. We conclude that a small number of persons with HIV infection continue to donate blood, despite attempts to exclude them, but that donors who test positive on enzyme immunoassay but persistently negative or indeterminate on Western blot assay probably do not represent a risk for the transmission of HIV. 相似文献
43.
Chicken pox infection (varicella zoster virus) and acute monoarthritis: evidence against a direct viral mechanism.
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A 9 year old boy developed acute monoarthritis of the left knee concurrent with the appearance of a varicella zoster virus (VZV) rash. Repeated VZV DNA hybridisation of the cells within the synovial fluid and synovial membrane failed to show any evidence of intracellular virus. Virus was isolated from synovial fluid 24 hours after the start of clinical infection but not later. These findings suggest that the mechanism of the arthritis is not due to viral replication inside the swollen joint. 相似文献
44.
Quantification of Human Immunodeficiency Virus Type 1 RNA Levels in Plasma by Using Small-Volume-Format Branched-DNA Assays 总被引:2,自引:0,他引:2
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![点击此处可从《Journal of clinical microbiology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Torange Yeghiazarian Yuqi Zhao Stanley E. Read William Kabat Xiaoyi Li Sarah J. Hamren Patrick J. Sheridan Judith C. Wilber David N. Chernoff Ram Yogev 《Journal of clinical microbiology》1998,36(7):2096-2098
We have developed small-volume (50 or 250 μl)-format branched-DNA assays for human immunodeficiency virus type 1 (HIV-1) RNA for use with specimens in which the volume is limited and/or a high viral load is anticipated. These formats exhibited good correlation with the standard 1-ml format; high specificity, reproducibility, and linearity; and no significant difference in the quantification of HIV-1 subtypes. 相似文献
45.
Preimplantation genetic diagnosis principles and ethics 总被引:4,自引:0,他引:4
46.
Life expectancy in British Marfan syndrome populations 总被引:2,自引:0,他引:2
JR Gray AB Bridges RR West L. McLeish AG Stuart JCS Dean MEM Porteous M. Boxer SJ Davies 《Clinical genetics》1998,54(2):124-128
A total of 206 patients with Marfan syndrome were ascertained throughout genetic clinics in Wales and Scotland during the period 1970–1990. There were 45 deaths representing 22% of the cohort. Mean age at death was 45.3 ± 16.5 years. 50% median cumulative survival in the total cohort (n = 206) was 53 years for males and 72 years for females. Multivariate analysis confirmed severity as the best independent indicator of survival. These findings and survival curves will assist in the counselling of British families and individuals with Marfan syndrome. 相似文献
47.
Frataxin is reduced in Friedreich ataxia patients and is associated with mitochondrial membranes 总被引:17,自引:8,他引:17
Campuzano V; Montermini L; Lutz Y; Cova L; Hindelang C; Jiralerspong S; Trottier Y; Kish SJ; Faucheux B; Trouillas P; Authier FJ; Durr A; Mandel JL; Vescovi A; Pandolfo M; Koenig M 《Human molecular genetics》1997,6(11):1771-1780
Friedreich ataxia is a progressive neurodegenerative disorder caused by
loss of function mutations in the frataxin gene. In order to unravel
frataxin function we developed monoclonal antibodies raised against
different regions of the protein. These antibodies detect a processed 18
kDa protein in various human and mouse tissues and cell lines that is
severely reduced in Friedreich ataxia patients. By immunocytofluorescence
and immunocytoelectron microscopy we show that frataxin is located in
mitochondria, associated with the mitochondrial membranes and crests.
Analysis of cellular localization of various truncated forms of frataxin
expressed in cultured cells and evidence of removal of an N-terminal
epitope during protein maturation demonstrated that the mitochondrial
targetting sequence is encoded by the first 20 amino acids. Given the
shared clinical features between Friedreich ataxia, vitamin E deficiency
and some mitochondriopathies, our data suggest that a reduction in frataxin
results in oxidative damage.
相似文献
48.
Recessively inherited L-DOPA-responsive parkinsonism in infancy caused by a point mutation (L205P) in the tyrosine hydroxylase gene 总被引:4,自引:0,他引:4
49.
The effect of Streptococcus pneumoniae pneumolysin on human respiratory epithelium in vitro 总被引:3,自引:0,他引:3
C Feldman T J Mitchell P W Andrew G J Boulnois R C Read H C Todd P J Cole R Wilson 《Microbial pathogenesis》1990,9(4):275-284
Streptococcus pneumoniae culture filtrates and pneumolysin both slow human ciliary beating and damage respiratory epithelium in vitro. A polyclonal pneumolysin antibody bound to sepharose beads removed pneumolysin from culture filtrates and showed that pneumolysin alone was responsible for the effects on epithelium. In a 48-h organ culture pneumolysin caused ciliary slowing and epithelial disruption in a dose-dependent manner down to 5 ng/ml. Comparison of the ciliary slowing activity and pneumolysin concentration in filtrates in a continuous broth culture showed a maximal effect at 16 h (pneumolysin 7.5 micrograms/ml). Later the activity decreased while the pneumolysin concentration increased (8.8 micrograms/ml). This loss of activity was prevented by neutralisation of the acid pH of the culture medium. Eight different culture filtrates produced significant (P less than 0.05) ciliary slowing which correlated (r = 0.95) with simultaneously measured haemolytic (pneumolysin) activity. Substitution of tryptophan (position 433) by phenylalanine reduced the haemolytic and ciliary slowing activity of pneumolysin, but did not affect its ability to activate complement. There was no correlation between the ciliary slowing produced by the culture filtrate and that produced by the autolysate of a particular strain, nor between ciliary slowing and the extent of autolysis or the serotype of the strain. 相似文献
50.