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41.
Tovanabutra S Kijak GH Beyrer C Gammon-Richardson C Sakkhachornphop S Vongchak T Jittiwutikarn J Razak MH Sanders-Buell E Robb ML Suriyanon V Birx DL Michael NL Celentano DD McCutchan FE 《AIDS research and human retroviruses》2007,23(6):829-833
In Thailand, the circulating HIV-1 strains include CRF01_AE, subtype B, and their recombinants. Genotyping and full-genome sequencing had previously identified circulating recombinant form CRF15_01B within a cohort of 347 HIV-1-infected individuals enrolled in the Opiate Users Research (OUR) study in northern Thailand. Using an improved MHAbce in six to eight genome regions and archived OUR serum samples, seven strains were identified with a new and complex 01/B recombinant pattern in common, different from that of CRF15_01B. Complete sequencing of three strains, amplified from serum as overlapping half-genomes, confirmed their common recombinant structure, mostly CRF01_AE, but with segments of subtype B in pol and gp41, plus a region of frequent 01/B crossovers in pol. OUR strains 1969P, 2275P, and 2478P were from individuals without direct epidemiological linkage and thus establish CRF34_01B. More comprehensive HIV-1 prevention and treatment programs in IDU can help to limit the growing complexity of HIV-1 strains in Thailand. 相似文献
42.
Kijak GH Janini M Tovanabutra S Sanders-Buell EE Birx DL Robb ML Michael NL McCutchan FE 《AIDS research and human retroviruses》2007,23(4):554-557
G-to-A hypermutation, a massive substitution of G for A, was first observed in HIV genomes 15 years ago. Initially ascribed to fluctuating nucleotide pools or PCR errors, it has now been recognized as the result of an important host-defense mechanism mediated by APOBECs, a family of sequence-specific cytidine deaminases. Levels of hypermutation vary, and APOBECs have different preferences for the sequence context of cytidines targeted for deamination; analysis of hypermutation provides important information about the host-virus interaction during viral replication. Here we present HyperPack, a software package to support systematic characterization of hypermutated sequences. Users can define the context of substitution for independent study of the effects of different APOBECs. The SubstrateScan and HyperScan modules are overlapping sliding-window strategies to analyze the distribution of targeted motifs and their substitution levels, respectively, across the viral genome. HyperPack is a platform-flexible, Java stand-alone application available through http://www.hivresearch.org/hyperpack/. 相似文献
43.
Chronic generalized fibrotic skin lesions from disseminated leishmaniasis caused by Leishmania martiniquensis in two patients from northern Thailand infected with HIV 下载免费PDF全文
44.
Beyrer C Razak MH Jittiwutikarn J Suriyanon V Vongchak T Srirak N Kawichai S Tovanabutra S Rungruengthanakit K Sawanpanyalert P Sripaipan T Celentano DD 《International journal of STD & AIDS》2004,15(10):697-704
Our objective was to determine sociodemographic, sexual and drug-use-related risk factors among methamphetamine (MA) users presenting for drug treatment in northern Thailand. Patients admitted for drug detoxification for MA and other drugs were studied cross-sectionally for risk factors associated with substance abuse and blood-borne and sexually transmitted pathogens. In all, 1865 (200 women) patients treated for MA, opiate, and mixed substance abuse between 1 February 1999 and 31 January 2000 completed all study procedures. Among 1865 participants, 750 (40.2%) were admitted for MA detoxification and 1115 (59.8%) for opiate (heroin, opium, or both) treatment. MA users were significantly younger, better educated, more likely to be Thai than highland ethnic minorities, and had significantly different sexual risks and sexually transmitted disease rates, including lower syphilis seropositivity and higher chlamydial prevalence, than persons admitted for opiate or mixed drug treatment. For those who reported MA use only, use by injection was rare and HIV infections significantly less common than among all other drug users. Thailand is undergoing an epidemic of MA use. These young users are a strikingly different population from opiate/heroin users in northern Thailand. MA users had higher rates of chlamydia infection than opiate users, reflecting their young age, and HIV rates in this population were lower than injecting drug users, but still elevated. MA use is a serious public health problem in Thailand and both improved prevention and treatment methodologies are urgently needed. 相似文献
45.
Tovanabutra S Beyrer C Sakkhachornphop S Razak MH Ramos GL Vongchak T Rungruengthanakit K Saokhieo P Tejafong K Kim B De Souza M Robb ML Birx DL Jittiwutikarn J Suriyanon V Celentano DD McCutchan FE 《AIDS research and human retroviruses》2004,20(5):465-475
CRF01_AE and subtype B have dominated the HIV-1 epidemic in Thailand since 1989. We reported a new circulating recombinant form of HIV-1, CRF15_01B, as well as other unique CRF01_AE/B recombinants among prevalent HIV infections in Thailand. We sought to study this challenging molecular picture through assessment of subtypes among recent HIV-1 seroconverters in northern Thai drug users. A total of 847 HIV-1 seronegative drug users (342 IDU and 505 non-IDU) were enrolled, from 1999 to 2002, in a prospective study; 39 HIV-1 incident cases were identified and characteristics were collected. The overall HIV-1 incidence rate was 2.54/100PY, but it was 10.0/100PY among male IDU. HIV was strongly associated with injection history; 38 of 39 seroconverters gave a history of IDU. A near full-length genome of HIV-1 was recovered by PCR amplification and sequenced from peripheral mononuclear cell extracted DNA of 38 seroconverters. Phylogenetic analysis revealed that 33 (86.8%) were CRF01_AE and 5 (13.2%) were CRF01_AE/B recombinants. These recombinants had different structure but shared some common breakpoints, indicating an ongoing recombination process. Recombinant infection increased with year of sampling (0 to 57.1%). The molecular epidemiology of HIV-1 among drug users in northern Thailand has thus entered a new era. CRF01_AE remains predominant while pure subtype B is becoming rare, and now a substantial component of the epidemic. These findings support the need for CRF01_AE and subtype B components in clade-matched vaccine strategies for Thai phase III trials. Ongoing molecular surveillance of circulating HIV-1 strains is imperative for the evaluation of HIV vaccine efficacy. 相似文献
46.
Hakre S Upshaw-Combs DR Sanders-Buell EE Scoville SL Kuper JD Jagodzinski LL Bradfield AN Davison DC Callis WG Owens AB Michael NL O'Connell RJ Peel SA Gardner JW Thompson ND Hu DJ Kim JH Tovanabutra S Scott PT LaFon SG;Insulin Pen Investigation Team 《Military medicine》2012,177(8):930-938
On January 30, 2009, nursing staff at a military hospital in Texas reported that single-patient use insulin pens were used on multiple patients. An investigation was initiated to determine if patient-to-patient bloodbome transmission occurred from the practice. Human immunodeficiency virus (HIV), hepatitis B virus (HBV), and hepatitis C virus (HCV) testing was offered to patients hospitalized from August 2007 to January 2009 and prescribed insulin pen injections. Virus from HCV-infected patients' sera was sequenced and compared for relatedness. An anonymous survey was administered to nurses. Of 2,113 patients prescribed insulin pen injections, 1,501 (71%) underwent testing; 6 (0.4%) were HIV positive, 6 (0.4%) were hepatitis B surface antigen positive, and 56 (3.7%) had HCV antibody. No viral sequences from 10 of 28 patients with newly diagnosed and 12 of 28 patients with preexisting HCV infection were closely related. Of 54 nurses surveyed, 74% reported being trained on insulin pen use, but 24% believed nurses used insulin pens on more than one patient. We found no clear evidence of bloodborne pathogen transmission. Training of hospital staff on correct use of insulin pens should be prioritized and their practices evaluated. Insulin pens should be more clearly labeled for single-patient use. 相似文献
47.
Jeffrey R Currier Unchalee Visawapoka Sodsai Tovanabutra Carl J Mason Deborah L Birx Francine E McCutchan Josephine H Cox 《BMC immunology》2006,7(1):1-17
Background
The early B lymphopoiesis in mammals is regulated through close interactions with stromal cells and components of the intracellular matrix in the bone marrow (BM) microenvironment. Although B lymphopoiesis has been studied for decades, the factors that are implicated in this process, both autocrine and paracrine, are inadequately explored. Wnt signaling is known to be involved in embryonic development and growth regulation of tissues and cancer. Wnt molecules are produced in the BM, and we here ask whether canonical Wnt signaling has a role in regulating human BM B lymphopoiesis.Results
Examination of the mRNA expression pattern of Wnt ligands, Fzd receptors and Wnt antagonists revealed that BM B progenitor cells and stromal cells express a set of ligands and receptors available for induction of Wnt signaling as well as antagonists for fine tuning of this signaling. Furthermore, different B progenitor maturation stages showed differential expression of Wnt receptors and co-receptors, β-catenin, plakoglobin, LEF-1 and TCF-4 mRNAs, suggesting canonical Wnt signaling as a regulator of early B lymphopoiesis. Exogenous Wnt3A induced stabilization and nuclear accumulation of β-catenin in primary lineage restricted B progenitor cells. Also, Wnt3A inhibited B lymphopoiesis of CD133+CD10- hematopoietic progenitor cells and CD10+ B progenitor cells in coculture assays using a supportive layer of stromal cells. This effect was blocked by the Wnt antagonists sFRP1 or Dkk1. Examination of early events in the coculture showed that Wnt3A inhibits cell division of B progenitor cells.Conclusion
These results indicate that canonical Wnt signaling is involved in human BM B lymphopoiesis where it acts as a negative regulator of cell proliferation in a direct or stroma dependent manner. 相似文献48.
Costello C Nelson KE Suriyanon V Sennun S Tovanabutra S Heilig CM Shiboski S Jamieson DJ Robison V Rungruenthanakit K Duerr A 《International journal of epidemiology》2005,34(3):577-584
BACKGROUND: In the continuing effort to introduce antiretroviral therapy in resource-limited settings, there is a need to understand differences between natural history of HIV in different populations and to identify feasible clinical measures predictive of survival. METHODS: We examined predictors of survival among 836 heterosexuals who were infected with HIV subtype CRF01_AE in Thailand. RESULTS: From 1993 to 1999, 269 (49.4%) men and 65 (25.7%) women died. The median time from the estimated seroconversion to death was 7.8 years (95% confidence interval 7.0-9.1). Men and women with enrolment CD4 counts <200 cells/microl had about 2 and 11 times greater risk of death than those with CD4 counts of 200-500 and >500, respectively. Measurements available in resource-limited settings, including total lymphocyte count (TLC), anaemia, and low body mass index (BMI), also predicted survival. Men with two or more of these predictors had a median survival of 0.8 (0.5-1.8) years, compared with 2.7 (1.9-3.3) years for one predictor and 4.9 (4.1-5.2) years for no predictors. CONCLUSIONS: The time from HIV infection to death appears shorter among this Thai population than among antiretroviral naive Western populations. CD4 count and viral load (VL) were strong, independent predictors of survival. When CD4 count and VL are unavailable, individuals at high risk for shortened HIV survival may be identified by a combination of low TLC, anaemia, and low BMI. This combination of accessible clinical measures of the disease stage may be useful for medical management in resource-limited settings. 相似文献
49.
Male viral load and heterosexual transmission of HIV-1 subtype E in northern Thailand 总被引:5,自引:0,他引:5
Tovanabutra S Robison V Wongtrakul J Sennum S Suriyanon V Kingkeow D Kawichai S Tanan P Duerr A Nelson KE 《Journal of acquired immune deficiency syndromes (1999)》2002,29(3):275-283
We evaluated the association between HIV-1 RNA copies/mL in men and heterosexual transmission to their female partners among 493 couples in Thailand. Husbands were identified as HIV-positive when they were screened as blood donors; nearly all were infected with HIV subtype E. Wives had no known risks for HIV infection other than sex with their husbands. In multivariate analysis, each log10 increment of HIV RNA in the man was associated with an 81% increased rate of HIV transmission to his wife (odds ratio = 1.81, 95% confidence interval: 1.33-2.48). No transmission occurred at viral loads below 1094 copies/mL, and a dose-response effect was seen with increasing viral load in the man. In multivariate analysis, a history of a sexually transmitted disease in the man or woman, longer duration of hormonal contraceptive use, and the woman's onset of sexual activity at less than 20 years of age were also associated with increased seropositivity of the wife. 相似文献
50.
Watanaveeradej V Benenson MW Souza MD Sirisopana N Nitayaphan S Tontichaivanich C Amphaipit R Renzullo PO Brown AE McNeil JG Robb ML Birx DL Tovanabutra S Carr JK McCutchan FE 《AIDS research and human retroviruses》2006,22(8):801-807
To characterize HIV-1 genotypes in candidate populations for a prime-boost phase III vaccine trial in Thailand, specimens from prevalent and incident HIV-1 infections from a family planning clinic population in Rayong Province and a community cohort in Chon Buri Province, collected from 1998 to 2001, were genotyped. A new multiregion hybridization assay, MHAbce, capable of distinguishing HIV-1 CRF01_AE, subtype B, and subtype C and their recombinants, was developed and applied to prevalent infections. Most incident and selected prevalent infections were studied by complete genome sequencing. By MHAbce, 168 of 194 prevalent infections were genotyped. Of these, 90.5% were CRF01_AE, 2.4% were subtype B, and 7.2% showed discordant or dual probe reactivity, indicative of recombination or dual infection, respectively. Among 23 incident infections, 20 were sequenced. Eighteen CRF01_AE, one subtype B, and one CRF01/B recombinant strains were seen. Two CRF01/B and one CRF01/C recombinant were identified among selected prevalent infections. These results indicate that incident and prevalent HIV-1 infections in Rayong and Chon Buri during 1998-2001 were 90% CRF01_AE, 3% subtype B, and 7% either recombinant or dual. This study frames the genetic diversity of HIV-1 in these cohorts in their preparatory phase for the ongoing ALVACHIV (vCP1521) prime, AIDSVAX B/E boost, phase III vaccine trial and will provide a benchmark for interpretation and analysis. 相似文献