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91.
Kapiga SH Sam NE Bang H Ni Q Ao TT Kiwelu I Chiduo S Ndibe U Seage G Coplan P Shao J Rosenberg ZF Essex M 《The Journal of infectious diseases》2007,195(9):1260-1269
BACKGROUND: We examined the role of herpes simplex virus type 2 (HSV-2) and other genital infections on human immunodeficiency virus type 1 (HIV-1) incidence in a cohort study conducted between 2002 and 2005 among female bar/hotel workers in Moshi, Tanzania. METHODS: At baseline and every 3 months thereafter, participants were interviewed, and blood and genital samples were collected. Predictors of HIV-1 incidence were evaluated using a Cox proportional hazards regression model. RESULTS: Of 845 women who were HIV-1 seronegative at baseline, 689 (81.5%) were monitored in the study for a total of 698.6 person-years at risk (PYARs). The overall HIV-1 incidence was 4.6/100 PYARs (95% confidence interval [CI], 3.0-6.2/100 PYARs), and condom use was very low. After adjustment for other risk factors, the risk of HIV-1 was increased among women with HSV-2 at baseline (hazard ratio [HR], 4.3 [95% CI, 1.5-12.4]) and in those who acquired HSV-2 during the study period (HR, 5.5 [95% CI, 1.2-25.4]). Other independent predictors of HIV-1 were baseline chlamydial infection (HR, 5.2), bacterial vaginosis (HR, 2.1), and the occurrence of genital ulcers (HR, 2.7). CONCLUSION: HSV-2 and other genital infections were the most important risk factors for HIV-1. Control of these infections could help to reduce HIV-1 incidence in this population. 相似文献
92.
Human immunodeficiency virus type 1 (HIV-1) evasion of host cytotoxic T lymphocyte (CTL) targeting is linked to the expression of variant amino acid residues, or escape mutations, in positions that alter the normal processing, presentation, or recognition of targeted epitopes. The combined genetic variability of HIV and the class I human leukocyte antigen (HLA) loci makes it difficult to characterize CTL escape mutations on a population level. However, a role in CTL escape may be inferred by identifying HIV amino acid polymorphisms that are specifically associated with particular HLA class I alleles. We describe here the results of a comprehensive analysis of HIV-1 subtype C (HIV-1C) to identify HLA class I-associated amino acid polymorphisms. We identified 94 HLA-associated amino acid polymorphisms distributed across the 15 major viral proteins analyzed. HLA-B alleles were involved in more associations (50%) than alleles from either the HLA-A (27%) or HLA-C (24%) loci. HLA-associated polymorphisms were identified in 18 of 26 previously described HIV-1C CTL immunoreactive regions including 7 of the 8 classified as immunodominant. Comparison to known HIV-1 CTL epitopes revealed that 19 of the HLA-associated polymorphisms were located in CTL epitopes restricted by the associated HLA allele. These results suggest that HIV-1C retains the potential for CTL escape across the entire proteome including regions that are broadly targeted on a population scale. The impact of CTL escape on natural and vaccine-induced CTL immunity warrants the continued characterization of the role of such HLA-associated polymorphisms in this process. 相似文献
93.
Novitsky V Wester CW DeGruttola V Bussmann H Gaseitsiwe S Thomas A Moyo S Musonda R Van Widenfelt E Marlink RG Essex M 《AIDS research and human retroviruses》2007,23(7):868-878
HIV-1C has become the dominant HIV-1 subtype in the global AIDS epidemic. Historically, the evolution of drug-resistant mutations was characterized primarily among antiretroviral (ARV)-treated HIV-1B infections. Whereas the non-B viruses are susceptible to the currently used ARVs, some differences between HIV-1 subtypes in response to ARV regimens have been reported. We analyzed the profile of ARV-associated mutations in HIV-1C infection treated with ZDV/ddI-containing regimens in an open-label, randomized 3 x 2 x 2 factorial study comparing ZDV/3TC vs. ZDV/ddI vs. d4T/3TC and EFV vs. NVP regimens in drug-naive adults in Botswana. The overall rate of virologic failure in the ZDV/ddI-containing arms was 14%. We addressed the development of NRTI-associated mutations in 23 virologically failed patients in the ZDV/ddI-containing arms. The 67N 70R 215Y genotype with wild-type amino acids at codon positions 41 and 210 was a dominant pattern of NRTI-associated mutations at the time of virologic failure. The mutation T215Y was the first step in the evolution of the 67N 70R 215Y genotype and was followed by mutations K70R and D67N. Representing a mixture of TAM-1 (41L/210W/215Y) and TAM-2 (67N/70R/215F /219Q) pathways, the 67N 70R 215Y genotype with wild-type amino acids at codon positions 41, 210, and 219 is a unique TAM pathway that is rarely seen in HIV-1B infection. Although limited by relatively small numbers, our data suggest that the 67N 70R 215Y genotype may be the HIV-1C-specific response to the first-line ZDV/ddI-containing regimen at the time of virologic failure. The presence of the 67N 70R 215Y genotype with wild-type amino acids at codon positions 41, 210, and 219 in HIV-1C infection suggests that the evolution of ARV-associated mutations and TAM pathways might be unique in non-B HIV-1 subtypes treated with particular ARV regimens. 相似文献
94.
95.
Background
Assessments for long-term incapacity for work are performed by Social Insurance Physicians (SIPs) who rely on interviews with claimants as an important part of the process. These interviews are susceptible to bias. In the Netherlands three protocols have been developed to conduct these interviews. These protocols are expert- and practice-based. We studied to what extent these protocols are adhered to by practitioners. 相似文献96.
Essex MJ Klein MH Cho E Kraemer HC 《Journal of the American Academy of Child and Adolescent Psychiatry》2003,42(6):728-737
OBJECTIVE: To investigate effects of the timing of initial exposure to maternal depression and marital conflict on kindergarten children's mental health symptoms. METHOD: For 406 families (of 570 originally recruited), mothers reported on major depression and marital conflict on multiple occasions in the child's infancy and toddler/preschool periods. Mothers and teachers completed the MacArthur Health and Behavior Questionnaire when children were in kindergarten. RESULTS: Children evidenced co-occurring internalizing and externalizing symptoms, although the mix was more toward internalizing for girls and externalizing for boys. Symptoms were more severe among children exposed to either adversity, and these effects were additive. Boys exposed to maternal depression in infancy had a preponderance of internalizing behaviors, but if subsequently exposed to marital conflict, the mix toward externalizing behaviors increased to match levels of clinic-referred children. For girls, the preponderance of internalizing symptoms increased to match levels of clinic-referred children when initial exposure to marital conflict occurred in the toddler/preschool period. CONCLUSIONS: It is important to consider both adversities across developmental periods, to distinguish the symptom severity from directionality, and to consider child gender. Prevention and intervention efforts that consider these findings are warranted. 相似文献
97.
J S Rhim K S Koh A Chen M Essex 《International journal of cancer. Journal international du cancer》1981,28(1):51-57
Tumorigenic clonal lines derived from soft agar colonies induced by DMBA-transformed feline embryo cells were isolated and characterized. The morphologically altered clonal cells formed large aggregates, growing in this aggregate form when suspended in liquid growth medium above an agar base and forming colonies in soft agar with high efficiency. When inoculated into athymic nude mice, chemically altered clonal cells produced progressively growing sarcomas. Cells established from the tumors morphologically resembled the DMBA-transformed feline embryo cells and were characterized as cat cells by karyological analysis. The tumorigenic lines were negative for feline oncornavirus-associated cell membrane antigen (FOCMA), and for "gag-X" the transformation-related polyprotein which is encoded by the replication defective feline sarcoma virus. 相似文献
98.
Williamson MR; Boyd CM; McGuire EL; Angtuaco T; Westbrook KC; Lang NP; Alston J; Broadwater JR; Navab F; Bersey ML 《Radiology》1986,159(1):272-273
The nuclear medicine bleeding scan is frequently insufficient to locate sites of bleeding precisely, in spite of its great sensitivity. A small, hand-held Geiger-Müller counter, placed directly on exposed intestine in the operating room, enables precise location of the probable bleeding site. In three patients, the technique allowed a minimal amount of intestine to be resected, distinguished between large- and small-intestinal hemorrhage, and eliminated other foci as sites of bleeding. 相似文献
99.
Mediastinal masses: alternative approaches to CT-guided needle biopsy 总被引:10,自引:1,他引:10
100.
J K Kreiss L W Kitchen H E Prince C K Kasper A L Goldstein P H Naylor O Preble J A Stewart M Essex 《The American journal of medicine》1986,80(3):345-350
A cohort of 63 hemophiliac subjects was followed for clinical and immunologic abnormalities related to the acquired immune deficiency syndrome (AIDS). When evaluated in early 1984, antibody to human T cell leukemia virus type III (HTLV-III) was detected in the serum of 59 percent (24 of 41) of factor VIII or IX concentrate recipients, but in none (0 of six) of the cryoprecipitate/fresh frozen plasma recipients. HTLV-III-seropositive hemophiliac subjects, on average, had been exposed to twice as much concentrate during the previous year as seronegative hemophiliac subjects. The seropositive group had a significantly lower mean helper/suppressor T cell ratio and absolute helper T cell level than the seronegative group. By early 1984, 13 hemophiliac subjects in the study population had lymphadenopathy and one had AIDS. Antibody to HTLV-III was detected in the serum of 13 of these 14 hemophiliac subjects with overt clinical disease. The prevalence of lymphadenopathy or AIDS among HTLV-III-seropositive hemophiliac subjects was 54 percent (13 of 24). It is concluded that HTLV-III antibody occurs with high frequency in hemophiliac subjects, and is related to the amount of factor VIII or IX concentrate infused. Over half of HTLV-III-seropositive hemophiliac subjects in this population had overt clinical disease with either lymphadenopathy or AIDS. 相似文献