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61.
62.
Gray GE Urban M Chersich MF Bolton C van Niekerk R Violari A Stevens W McIntyre JA;PEP Study Group 《AIDS (London, England)》2005,19(12):1289-1297
BACKGROUND: Single-dose nevirapine (NVP) prophylaxis to mother and infant is widely used in resource-constrained settings for preventing mother-to-child transmission (MTCT) of HIV-1. Where women do not access antenatal care or HIV testing, postexposure prophylaxis to the infant may be an important preventative strategy. METHODS: This multicentre, randomized, open-label clinical trial (October 2000 to September 2002) in South Africa compared single-dose NVP with 6 weeks of zidovudine (ZDV), commenced within 24 h of delivery among 1051 infants whose mothers had no prior antiretroviral therapy. HIV-1 infection rates were ascertained at birth, and at 6 and 12 weeks of age. Kaplan-Meier survival methods were used to estimate HIV-1 infection rates in an intention-to-treat analysis. RESULTS: Overall, 6 week and 12 week MTCT probability was 12.8% [95% confidence interval (CI),10.5-15.0] and 16.3% (95% CI,13.4-19.2), respectively. At 12 weeks, among infants who were not infected at birth, 24 (7.9%) infections occurred in the NVP arm and 41 (13.1%) in the ZDV arm (log rank P = 0.06). Using multivariate analysis, factors associated with infection following birth were ZDV use [odds ratio (OR), 1.8; 95% CI,1.1-3.2; P = 0.032), maternal CD4 cell count < 500 x 10(6) cells/l (OR, 2.5; 95% CI,1.3-5.0; P = 0.007), maternal viral load > 50 000 copies/ml (OR, 3.6; 95% CI,2.0-6.2; P < 0.0001) and breastfeeding (OR, 2.2; 95% CI,1.3-3.8; P = 0.006). CONCLUSION: A single-dose of NVP given to infants offers protection against HIV-1 infection and should be a strategy used in infants of mothers with untreated HIV infection. 相似文献
63.
C. Baboonian D. Halliday P. J. W. Venables T. Pawlowski G. Millman R. N. Maini 《Rheumatology international》1989,9(3-5):161-166
Summary Antibodies to rheumatoid arthritis nuclear antigen (RANA) are four- to sixfold increased in sera from patients with rheumatoid arthritis (RA), whereas levels of antibodies to other EBV encoded antigens are slightly elevated or normal. We have demonstrated that the major epitopes recognised by anti-RANA antibodies are represented by a synthetic peptide, P62, corresponding to part of the internal repeat sequence which contains only the amino acids glycine and alanine. In an enzyme-linked immunosorbent assay, anti-P62 antibodies in rheumatoid arthritis sera were four fold higher than healthy and disease controls. By contrast, levels of antibodies to a cloned fusion protein, representing the C-terminus of EBNA-1 and excluding the IR3 region, were normal in RA, but elevated fivefold in nasopharyngeal carcinoma (NPC). Affinity purified anti-P62 antibodies reacted with EBNA-1 and RANA but also with a 60 kD protein present in tissue extracts which has been tentatively identified as cytokeratin. This suggests that the specific increase of anti-P62 antibodies in RA may be due to cross-reactions with autoantibodies to structural proteins with repeat sequences containing glycine. Such sequences are found in cytokeratin and proteoglycans, suggesting that anti-P62 (and hence anti-RANA) antibodies may be cross-reactive antibodies of pathogenic significance in RA, though not necessarily indicating an aetiological role for EBV. 相似文献
64.
Carlos Alberto Nigro Eduardo Dibur Eduardo Borsini Silvana Malnis Glenda Ernst Ignacio Bledel Sergio González Anabella Arce Facundo Nogueira 《Sleep & breathing》2018,22(3):683-693
Background
It has been reported that the clinical expression of obstructive sleep apnea (OSA) may differ in women and men.Objective
The objective of this study was to evaluate the influence of gender on reported OSA-related symptoms in a large clinical population of patients.Methods
The database from the sleep laboratory of a tertiary care center was examined. Adult patients who had undergone a diagnostic polysomnography and completed the Berlin questionnaire, a sleep questionnaire, and the Epworth sleepiness scale were selected. Multiple logistic regression analysis was performed to assess the relationship between OSA-associated symptoms and different potential explanatory variables.Results
The study sample included 1084 patients, median age was 53 years, 46.5% (504) were women, 72.7% (788) had OSA (apnea/hypopnea index ≥?5), and 31.2% were obese. After adjusting for age, body mass index, and apnea/hypopnea index, men were more likely to report snoring (OR 4.06, p?<?0.001), habitual or loud snoring (OR 2.34, p?<?0.001; 2.14, p?<?0.001, respectively) and apneas (OR 2.44, p?<?0.001), than women. After controlling for multiple variables, female gender was an independent predictive factor for reported tiredness (OR 0.57, p 0.001), sleep onset insomnia (OR 0.59, p 0.0035), and morning headaches (OR 0.32, p?<?0.001). Reports of excessive daytime sleepiness, nocturia, midnight insomnia, and subjective cognitive complaints were not significantly associated with gender.Conclusion
Women with OSA were more likely to report tiredness, initial insomnia, and morning headaches, and less likely to complain of typical OSA symptoms (snoring, apneas) than men.65.
Human fetal adenohypophysis. Electron microscopic and ultrastructural immunocytochemical analysis 总被引:4,自引:0,他引:4
S L Asa K Kovacs E Horvath N E Losinski F A Laszlo I Domokos W C Halliday 《Neuroendocrinology》1988,48(4):423-431
The pituitary glands were removed from 63 human fetuses from 5 weeks of gestation to term and studied by electron microscopy and ultrastructural immunocytochemistry to document the development of cell differentiation and hormone production in the adenohypophysis. At 5 weeks of gestation, Rathke's cleft was lined by columnar epithelium with abundant cytoplasmic glycogen and occasional secretory granules. By 6 weeks of gestation, cells resembling corticotrophs were identified; in 8-week-old fetuses, type I microfilaments were found in those cells. Well-differentiated somatotrophs were seen in adenohypophyses of 8- to 9-week-old fetuses. Although secretory granules were numerous, the Golgi complex was inconspicuous in early fetal glands. After 10 weeks of gestation, there was a change with morphologic evidence of active hormone secretion; large Golgi regions and sparsely granulated cells were found. Some somatotrophs at this stage contained aggregates of type II microfilaments which resembled the fibrous bodies of sparsely granulated somatotroph adenomas. Densely granulated mammosomatotrophs containing growth hormone and prolactin were identified at 12 weeks of gestation. Cells with characteristics of the glycoprotein hormone cell line were seen in pituitaries at 12 weeks of gestation; thyrotrophs and gonadotrophs were identified after 15 weeks. Typical lactotrophs were not recognized before 23 weeks, but were numerous in pituitaries of fetuses older than 35 weeks. This study documents for the first time the existence of a bihormonal mammosomatotroph in the human fetal pituitary and confirms that somatotrophs and lactotrophs, the two acidophil cell types, are embryologically related.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
66.
Kathryn Rough Janan Dietrich Thandekile Essien David J. Grelotti David R. Bansberg Glenda Gray Ingrid T. Katz 《AIDS and behavior》2014,18(7):1378-1380
Media reports have described recreational use of HIV antiretroviral medication in South Africa, but little has been written about this phenomenon in the scientific literature. We present original, qualitative data from eight semi-structured interviews that characterize recreational antiretroviral use in Soweto, South Africa. Participants reported that antiretrovirals, likely efavirenz, are crushed, mixed with illicit drugs (in a mixture known as whoonga), and smoked. They described medications being stolen from patients and expressed concern that antiretroviral abuse jeopardized the safety of both patients and users. Further studies are needed to understand the prevalence, patterns, and consequences of antiretroviral abuse and diversion. 相似文献
67.
Jian-Hua Wang Amany Gouda-Vossos Nicolas Dzamko Glenda Halliday Yue Huang 《神经科学通报》2013,29(5):649-654
Both fresh-frozen and formalin-fixed,paraffinembedded(FFPE)human brain tissues are invaluable resources for molecular genetic studies of central nervous system diseases,especially neurodegenerative disorders.To identify the optimal method for DNA extraction from human brain tissue,we compared methods on differently-processed tissues.Fragments of LRRK2 and MAPT(257 bp and 483 bp/245 bp)were amplified for evaluation.We found that for FFPE samples,the success rate of DNA extraction was greater when using a commercial kit than a laboratory-based method(successful DNA extraction from 76%versus 33%of samples).PCR amplicon size and storage period were key factors influencing the success rate of DNA extraction from FFPE samples.In the fresh-frozen samples,the DNA extraction success rate was 100%using either a commercial kit(QIAamp DNA Micro)or a laboratorybased method(sample boiling in 0.1 mol/L NaOH,followed by proteinase K digestion,and then DNA extraction using Chelex-100)regardless of PCR amplicon length or tissue storage time.Although the present results demonstrate that PCR-amplifiable genomic DNA can be extracted from both fresh-frozen and FFPE samples,fresh brain tissue is recommended for DNA extraction in future neuropathological studies. 相似文献
68.
69.
Venkatesh KK de Bruyn G Lurie MN Modisenyane T Triche EW Gray GE Welte A Martinson NA 《AIDS and behavior》2012,16(1):139-150
We studied 1163 sexually-active HIV-infected South African men and women in an urban primary care program to understand patterns
of sexual behaviors and whether these behaviors differed by partner HIV status. Overall, 40% reported a HIV-positive partner
and 60% a HIV-negative or status unknown partner; and 17.5% reported >2 sex acts in the last 2 weeks, 16.4% unprotected sex
in the last 6 months, and 3.7% >1 sex partner in the last 6 months. Antiretroviral therapy (ART) was consistently associated
with decreased sexual risk behaviors, as well as with reporting a HIV-negative or status unknown partner. The odds of sexual
risk behaviors differed by sex; and were generally higher among participants reporting a HIV-positive partner, but continued
among those with a HIV-negative or status unknown partner. These data support ART as a means of HIV prevention. Engaging in
sexual risk behaviors primarily with HIV-positive partners was not widely practiced in this setting, emphasizing the need
for couples-based prevention. 相似文献
70.