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1.  Sensitive Deep-Sequencing-Based HIV-1 Genotyping Assay To Simultaneously Determine Susceptibility to Protease, Reverse Transcriptase, Integrase, and Maturation Inhibitors, as Well as HIV-1 Coreceptor Tropism 
With 29 individual antiretroviral drugs available from six classes that are approved for the treatment of HIV-1 infection, a combination of different phenotypic and genotypic tests is currently needed to monitor HIV-infected individuals. In this study, we developed a novel HIV-1 genotypic assay based on deep sequencing (DeepGen HIV) to simultaneously assess HIV-1 susceptibilities to all drugs targeting the three viral enzymes and to predict HIV-1 coreceptor tropism. Patient-derived gag-p2/NCp7/p1/p6/pol-PR/RT/IN- and env-C2V3 PCR products were sequenced using the Ion Torrent Personal Genome Machine. Reads spanning the 3′ end of the Gag, protease (PR), reverse transcriptase (RT), integrase (IN), and V3 regions were extracted, truncated, translated, and assembled for genotype and HIV-1 coreceptor tropism determination. DeepGen HIV consistently detected both minority drug-resistant viruses and non-R5 HIV-1 variants from clinical specimens with viral loads of ≥1,000 copies/ml and from B and non-B subtypes. Additional mutations associated with resistance to PR, RT, and IN inhibitors, previously undetected by standard (Sanger) population sequencing, were reliably identified at frequencies as low as 1%. DeepGen HIV results correlated with phenotypic (original Trofile, 92%; enhanced-sensitivity Trofile assay [ESTA], 80%; TROCAI, 81%; and VeriTrop, 80%) and genotypic (population sequencing/Geno2Pheno with a 10% false-positive rate [FPR], 84%) HIV-1 tropism test results. DeepGen HIV (83%) and Trofile (85%) showed similar concordances with the clinical response following an 8-day course of maraviroc monotherapy (MCT). In summary, this novel all-inclusive HIV-1 genotypic and coreceptor tropism assay, based on deep sequencing of the PR, RT, IN, and V3 regions, permits simultaneous multiplex detection of low-level drug-resistant and/or non-R5 viruses in up to 96 clinical samples. This comprehensive test, the first of its class, will be instrumental in the development of new antiretroviral drugs and, more importantly, will aid in the treatment and management of HIV-infected individuals.
doi:10.1128/AAC.02710-13
PMCID: PMC4023761  PMID: 24468782
2.  Contribution of Human Immunodeficiency Virus Type 1 Minority Variants to Reduced Drug Susceptibility in Patients on an Integrase Strand Transfer Inhibitor-Based Therapy 
PLoS ONE  2014;9(8):e104512.
The role of HIV-1 minority variants on transmission, pathogenesis, and virologic failure to antiretroviral regimens has been explored; however, most studies of low-level HIV-1 drug-resistant variants have focused in single target regions. Here we used a novel HIV-1 genotypic assay based on deep sequencing, DEEPGEN (Gibson et al 2014 Antimicrob Agents Chemother 58∶2167) to simultaneously analyze the presence of minority variants carrying mutations associated with reduced susceptibility to protease (PR), reverse transcriptase (RT), and integrase strand transfer integrase inhibitors (INSTIs), as well as HIV-1 coreceptor tropism. gag-p2/NCp7/p1/p6/pol-PR/RT/INT and env/C2V3 PCR products were obtained from twelve heavily treatment-experienced patients experiencing virologic failure while participating in a 48-week dose-ranging study of elvitegravir (GS-US-183-0105). Deep sequencing results were compared with (i) virological response to treatment, (ii) genotyping based on population sequencing, (iii) phenotyping data using PhenoSense and VIRALARTS, and (iv) HIV-1 coreceptor tropism based on the phenotypic test VERITROP. Most patients failed the antiretroviral regimen with numerous pre-existing mutations in the PR and RT, and additionally newly acquired INSTI-resistance mutations as determined by population sequencing (mean 9.4, 5.3, and 1.4 PI- RTI-, and INSTI-resistance mutations, respectively). Interestingly, since DEEPGEN allows the accurate detection of amino acid substitutions at frequencies as low as 1% of the population, a series of additional drug resistance mutations were detected by deep sequencing (mean 2.5, 1.5, and 0.9, respectively). The presence of these low-abundance HIV-1 variants was associated with drug susceptibility, replicative fitness, and coreceptor tropism determined using sensitive phenotypic assays, enhancing the overall burden of resistance to all four antiretroviral drug classes. Further longitudinal studies based on deep sequencing tests will help to clarify (i) the potential impact of minority HIV-1 drug resistant variants in response to antiretroviral therapy and (ii) the importance of the detection of HIV minority variants in the clinical practice.
doi:10.1371/journal.pone.0104512
PMCID: PMC4128663  PMID: 25110880
3.  Seriously Mentally Ill Women’s Safer Sex Behaviors and the Theory of Reasoned Action 
Seriously mentally ill women at risk for HIV infection (n = 96) participated in structured interviews assessing sexual and substance use behavior over a 3-month period. The majority of the women (63.5%) did not use condoms. Consistent with the Theory of Reasoned Action, condom use attitudes and perceived social norms about safer sex were associated with safer sex intentions. Supplementing TRA variables with safer sex self-efficacy explained additional variance in safer sex intentions. Greater safer sex intentions were related to both greater condom use and to less frequent unprotected intercourse. In addition, less frequent sex after drug use and a less fatalistic outlook were associated with less frequent unprotected intercourse. Life circumstances specific to this population are particularly important to examine to improve the effectiveness of risk reduction interventions for seriously mentally ill women.
doi:10.1177/1090198108324597
PMCID: PMC4107413  PMID: 19458268
sexual risk behavior; HIV/AIDS; severe mental illness
4.  Assembly information services in the European Nucleotide Archive 
Nucleic Acids Research  2013;42(Database issue):D38-D43.
The European Nucleotide Archive (ENA; http://www.ebi.ac.uk/ena) is a repository for the world public domain nucleotide sequence data output. ENA content covers a spectrum of data types including raw reads, assembly data and functional annotation. ENA has faced a dramatic growth in genome assembly submission rates, data volumes and complexity of datasets. This has prompted a broad reworking of assembly submission services, for which we now reach the end of a major programme of work and many enhancements have already been made available over the year to components of the submission service. In this article, we briefly review ENA content and growth over 2013, describe our rapidly developing services for genome assembly information and outline further major developments over the last year.
doi:10.1093/nar/gkt1082
PMCID: PMC3965037  PMID: 24214989
5.  Sensitive Cell-Based Assay for Determination of Human Immunodeficiency Virus Type 1 Coreceptor Tropism 
Journal of Clinical Microbiology  2013;51(5):1517-1527.
CCR5 antagonists are a powerful new class of antiretroviral drugs that require a companion assay to evaluate the presence of CXCR4-tropic (non-R5) viruses prior to use in human immunodeficiency virus (HIV)-infected individuals. In this study, we have developed, characterized, verified, and prevalidated a novel phenotypic test to determine HIV-1 coreceptor tropism (VERITROP) based on a sensitive cell-to-cell fusion assay. A proprietary vector was constructed containing a near-full-length HIV-1 genome with the yeast uracil biosynthesis (URA3) gene replacing the HIV-1 env coding sequence. Patient-derived HIV-1 PCR products were introduced by homologous recombination using an innovative yeast-based cloning strategy. The env-expressing vectors were then used in a cell-to-cell fusion assay to determine the presence of R5 and/or non-R5 HIV-1 variants within the viral population. Results were compared with (i) the original version of Trofile (Monogram Biosciences, San Francisco, CA), (ii) population sequencing, and (iii) 454 pyrosequencing, with the genotypic data analyzed using several bioinformatics tools, i.e., the 11/24/25 rule, Geno2Pheno (2% to 5.75%, 3.5%, or 10% false-positive rate [FPR]), and webPSSM. VERITROP consistently detected minority non-R5 variants from clinical specimens, with an analytical sensitivity of 0.3%, with viral loads of ≥1,000 copies/ml, and from B and non-B subtypes. In a pilot study, a 73.7% (56/76) concordance was observed with the original Trofile assay, with 19 of the 20 discordant results corresponding to non-R5 variants detected using VERITROP and not by the original Trofile assay. The degree of concordance of VERITROP and Trofile with population and deep sequencing results depended on the algorithm used to determine HIV-1 coreceptor tropism. Overall, VERITROP showed better concordance with deep sequencing/Geno2Pheno at a 0.3% detection threshold (67%), whereas Trofile matched better with population sequencing (79%). However, 454 sequencing using Geno2Pheno at a 10% FPR and 0.3% threshold and VERITROP more accurately predicted the success of a maraviroc-based regimen. In conclusion, VERITROP may promote the development of new HIV coreceptor antagonists and aid in the treatment and management of HIV-infected individuals prior to and/or during treatment with this class of drugs.
doi:10.1128/JCM.00092-13
PMCID: PMC3647936  PMID: 23486708
6.  Facing growth in the European Nucleotide Archive 
Nucleic Acids Research  2012;41(Database issue):D30-D35.
The European Nucleotide Archive (ENA; http://www.ebi.ac.uk/ena/) collects, maintains and presents comprehensive nucleic acid sequence and related information as part of the permanent public scientific record. Here, we provide brief updates on ENA content developments and major service enhancements in 2012 and describe in more detail two important areas of development and policy that are driven by ongoing growth in sequencing technologies. First, we describe the ENA data warehouse, a resource for which we provide a programmatic entry point to integrated content across the breadth of ENA. Second, we detail our plans for the deployment of CRAM data compression technology in ENA.
doi:10.1093/nar/gks1175
PMCID: PMC3531187  PMID: 23203883
7.  Use of Four Next-Generation Sequencing Platforms to Determine HIV-1 Coreceptor Tropism 
PLoS ONE  2012;7(11):e49602.
HIV-1 coreceptor tropism assays are required to rule out the presence of CXCR4-tropic (non-R5) viruses prior treatment with CCR5 antagonists. Phenotypic (e.g., Trofile™, Monogram Biosciences) and genotypic (e.g., population sequencing linked to bioinformatic algorithms) assays are the most widely used. Although several next-generation sequencing (NGS) platforms are available, to date all published deep sequencing HIV-1 tropism studies have used the 454™ Life Sciences/Roche platform. In this study, HIV-1 co-receptor usage was predicted for twelve patients scheduled to start a maraviroc-based antiretroviral regimen. The V3 region of the HIV-1 env gene was sequenced using four NGS platforms: 454™, PacBio® RS (Pacific Biosciences), Illumina®, and Ion Torrent™ (Life Technologies). Cross-platform variation was evaluated, including number of reads, read length and error rates. HIV-1 tropism was inferred using Geno2Pheno, Web PSSM, and the 11/24/25 rule and compared with Trofile™ and virologic response to antiretroviral therapy. Error rates related to insertions/deletions (indels) and nucleotide substitutions introduced by the four NGS platforms were low compared to the actual HIV-1 sequence variation. Each platform detected all major virus variants within the HIV-1 population with similar frequencies. Identification of non-R5 viruses was comparable among the four platforms, with minor differences attributable to the algorithms used to infer HIV-1 tropism. All NGS platforms showed similar concordance with virologic response to the maraviroc-based regimen (75% to 80% range depending on the algorithm used), compared to Trofile (80%) and population sequencing (70%). In conclusion, all four NGS platforms were able to detect minority non-R5 variants at comparable levels suggesting that any NGS-based method can be used to predict HIV-1 coreceptor usage.
doi:10.1371/journal.pone.0049602
PMCID: PMC3498215  PMID: 23166726
8.  Novel Method for Simultaneous Quantification of Phenotypic Resistance to Maturation, Protease, Reverse Transcriptase, and Integrase HIV Inhibitors Based on 3′Gag(p2/p7/p1/p6)/PR/RT/INT-Recombinant Viruses: a Useful Tool in the Multitarget Era of Antiretroviral Therapy▿† 
Twenty-six antiretroviral drugs (ARVs), targeting five different steps in the life cycle of the human immunodeficiency virus type 1 (HIV-1), have been approved for the treatment of HIV-1 infection. Accordingly, HIV-1 phenotypic assays based on common cloning technology currently employ three, or possibly four, different recombinant viruses. Here, we describe a system to assess HIV-1 resistance to all drugs targeting the three viral enzymes as well as viral assembly using a single patient-derived, chimeric virus. Patient-derived p2-INT (gag-p2/NCp7/p1/p6/pol-PR/RT/IN) products were PCR amplified as a single fragment (3,428 bp) or two overlapping fragments (1,657 bp and 2,002 bp) and then recombined into a vector containing a near-full-length HIV-1 genome with the Saccharomyces cerevisiae uracil biosynthesis gene (URA3) replacing the 3,428 bp p2-INT segment (Dudley et al., Biotechniques 46:458–467, 2009). P2-INT-recombinant viruses were employed in drug susceptibility assays to test the activity of protease (PI), nucleoside/nucleotide reverse transcriptase (NRTI), nonnucleoside reverse transcriptase (NNRTI), and integrase strand-transfer (INSTI) inhibitors. Using a single standardized test (ViralARTS HIV), this new technology permits the rapid and automated quantification of phenotypic resistance for all known and candidate antiretroviral drugs targeting all viral enzymes (PR, RT, including polymerase and RNase H activities, and IN), some of the current and potential assembly inhibitors, and any drug targeting Pol or Gag precursor cleavage sites (relevant for PI and maturation inhibitors) This novel assay may be instrumental (i) in the development and clinical assessment of novel ARV drugs and (ii) to monitor patients failing prior complex treatment regimens.
doi:10.1128/AAC.00396-11
PMCID: PMC3147656  PMID: 21628544
9.  An observational study of the discrediting of COX-2 NSAIDs in Australia: Vioxx or class effect? 
BMC Public Health  2011;11:892.
Background
When a medicine such as rofecoxib (Vioxx) is withdrawn, or a whole class of medicines discredited such as the selective COX-2 inhibitors (COX-2s), follow-up of impacts at consumer level can be difficult and costly. The Australian Longitudinal Study on Women's Health provides a rare opportunity to examine individual consumer medicine use following a major discrediting event, the withdrawal of rofecoxib and issuing of safety warnings on the COX-2 class of medicines. The overall objective of this paper was to examine the impact of this discrediting event on dispensing of the COX-2 class of medicines, by describing medicine switching behaviours of older Australian women using rofecoxib in September 2004; the uptake of other COX-2s; and the characteristics of women who continued using a COX-2.
Methods
Participants were concessional beneficiary status women from the Older cohort (born 1921-26) of the Australian Longitudinal Study on Women's Health who consented to linkage to Pharmaceutical Benefits Scheme data, with at least one rofecoxib prescription dispensed in the 12 months before rofecoxib withdrawal. A prescription was defined as one dispensing occasion. Women were grouped by rofecoxib pattern of use: continuous (nine or more prescriptions dispensed in the 12 months prior to rofecoxib withdrawal) or non-continuous (eight or less prescriptions dispensed in the 12 months prior to rofecoxib withdrawal) users. Incidence rate per 100,000 person days and incidence risk ratio described uptake of alternate medicines, following rofecoxib withdrawal. Kaplan-Meier curves described differences in uptake patterns by medicine and pattern of rofecoxib use. Patterns of use of COX-2s in the next 100 days after first COX-2 uptake were described.
Results
Medicine switches and pattern of medicines uptake differed significantly depending upon whether a woman was a continuous or non-continuous rofecoxib user prior to rofecoxib discrediting. Continuous rofecoxib users overwhelmingly switched to another COX-2 and remained continuing COX-2 users for at least 100 days post-switch.
Conclusions
The typical switching behaviour of this group of women suggests that the issues leading to the discrediting of rofecoxib were not seen as a COX-2 class effect by prescribers to this high use group of consumers.
doi:10.1186/1471-2458-11-892
PMCID: PMC3280381  PMID: 22114865
10.  Major submissions tool developments at the European nucleotide archive 
Nucleic Acids Research  2011;40(Database issue):D43-D47.
The European Nucleotide Archive (ENA; http://www.ebi.ac.uk/ena), Europe's primary nucleotide sequence resource, captures and presents globally comprehensive nucleic acid sequence and associated information. Covering the spectrum from raw data to assembled and functionally annotated genomes, the ENA has witnessed a dramatic growth resulting from advances in sequencing technology and ever broadening application of the methodology. During 2011, we have continued to operate and extend the broad range of ENA services. In particular, we have released major new functionality in our interactive web submission system, Webin, through developments in template-based submissions for annotated sequences and support for raw next-generation sequence read submissions.
doi:10.1093/nar/gkr946
PMCID: PMC3245037  PMID: 22080548
11.  The European Nucleotide Archive 
Nucleic Acids Research  2010;39(Database issue):D28-D31.
The European Nucleotide Archive (ENA; http://www.ebi.ac.uk/ena) is Europe’s primary nucleotide-sequence repository. The ENA consists of three main databases: the Sequence Read Archive (SRA), the Trace Archive and EMBL-Bank. The objective of ENA is to support and promote the use of nucleotide sequencing as an experimental research platform by providing data submission, archive, search and download services. In this article, we outline these services and describe major changes and improvements introduced during 2010. These include extended EMBL-Bank and SRA-data submission services, extended ENA Browser functionality, support for submitting data to the European Genome-phenome Archive (EGA) through SRA, and the launch of a new sequence similarity search service.
doi:10.1093/nar/gkq967
PMCID: PMC3013801  PMID: 20972220
12.  CCR5- and CXCR4-Tropic Subtype C Human Immunodeficiency Virus Type 1 Isolates Have a Lower Level of Pathogenic Fitness than Other Dominant Group M Subtypes: Implications for the Epidemic▿ ‡  
Journal of Virology  2009;83(11):5592-5605.
Human immunodeficiency virus type 1 (HIV-1) subtype C is the dominant subtype globally, due largely to the incidence of subtype C infections in sub-Saharan Africa and east Asia. We compared the relative replicative fitness (ex vivo) of the major (M) group of HIV-1 subtypes A, B, C, D, and CRF01_AE and group O isolates. To estimate pathogenic fitness, pairwise competitions were performed between CCR5-tropic (R5) or CXCR4-tropic (X4) virus isolates in peripheral blood mononuclear cells (PBMC). A general fitness order was observed among 33 HIV-1 isolates; subtype B and D HIV-1 isolates were slightly more fit than the subtype A and dramatically more fit than the 12 subtype C isolates. All group M isolates were more fit (ex vivo) than the group O isolates. To estimate ex vivo transmission fitness, a subset of primary HIV-1 isolates were examined in primary human explants from penile, cervical, and rectal tissues. Only R5 isolates and no X4 HIV-1 isolates could replicate in these tissues, whereas the spread to PM1 cells was dependent on active replication and passive virus transfer. In tissue competition experiments, subtype C isolates could compete with and, in some cases, even win over subtype A and D isolates. However, when the migratory cells from infected tissues were mixed with a susceptible cell line, the subtype C isolates were outcompeted by other subtypes, as observed in experiments with PBMC. These findings suggest that subtype C HIV-1 isolates might have equal transmission fitness but reduced pathogenic fitness relative to other group M HIV-1 isolates.
doi:10.1128/JVI.02051-08
PMCID: PMC2681953  PMID: 19297481
13.  Improvements to services at the European Nucleotide Archive 
Nucleic Acids Research  2009;38(Database issue):D39-D45.
The European Nucleotide Archive (ENA; http://www.ebi.ac.uk/ena) is Europe’s primary nucleotide sequence archival resource, safeguarding open nucleotide data access, engaging in worldwide collaborative data exchange and integrating with the scientific publication process. ENA has made significant contributions to the collaborative nucleotide archival arena as an active proponent of extending the traditional collaboration to cover capillary and next-generation sequencing information. We have continued to co-develop data and metadata representation formats with our collaborators for both data exchange and public data dissemination. In addition to the DDBJ/EMBL/GenBank feature table format, we share metadata formats for capillary and next-generation sequencing traces and are using and contributing to the NCBI SRA Toolkit for the long-term storage of the next-generation sequence traces. During the course of 2009, ENA has significantly improved sequence submission, search and access functionalities provided at EMBL–EBI. In this article, we briefly describe the content and scope of our archive and introduce major improvements to our services.
doi:10.1093/nar/gkp998
PMCID: PMC2808951  PMID: 19906712
14.  DNA sequence of human chromosome 17 and analysis of rearrangement in the human lineage 
Zody, Michael C. | Garber, Manuel | Adams, David J. | Sharpe, Ted | Harrow, Jennifer | Lupski, James R. | Nicholson, Christine | Searle, Steven M. | Wilming, Laurens | Young, Sarah K. | Abouelleil, Amr | Allen, Nicole R. | Bi, Weimin | Bloom, Toby | Borowsky, Mark L. | Bugalter, Boris E. | Butler, Jonathan | Chang, Jean L. | Chen, Chao-Kung | Cook, April | Corum, Benjamin | Cuomo, Christina A. | de Jong, Pieter J. | DeCaprio, David | Dewar, Ken | FitzGerald, Michael | Gilbert, James | Gibson, Richard | Gnerre, Sante | Goldstein, Steven | Grafham, Darren V. | Grocock, Russell | Hafez, Nabil | Hagopian, Daniel S. | Hart, Elizabeth | Norman, Catherine Hosage | Humphray, Sean | Jaffe, David B. | Jones, Matt | Kamal, Michael | Khodiyar, Varsha K. | LaButti, Kurt | Laird, Gavin | Lehoczky, Jessica | Liu, Xiaohong | Lokyitsang, Tashi | Loveland, Jane | Lui, Annie | Macdonald, Pendexter | Major, John E. | Matthews, Lucy | Mauceli, Evan | McCarroll, Steven A. | Mihalev, Atanas H. | Mudge, Jonathan | Nguyen, Cindy | Nicol, Robert | O'Leary, Sinéad B. | Osoegawa, Kazutoyo | Schwartz, David C. | Shaw-Smith, Charles | Stankiewicz, Pawel | Steward, Charles | Swarbreck, David | Venkataraman, Vijay | Whittaker, Charles A. | Yang, Xiaoping | Zimmer, Andrew R. | Bradley, Allan | Hubbard, Tim | Birren, Bruce W. | Rogers, Jane | Lander, Eric S. | Nusbaum, Chad
Nature  2006;440(7087):1045-1049.
Chromosome 17 is unusual among the human chromosomes in many respects. It is the largest human autosome with orthology to only a single mouse chromosome1, mapping entirely to the distal half of mouse chromosome 11. Chromosome 17 is rich in protein-coding genes, having the second highest gene density in the genome2,3. It is also enriched in segmental duplications, ranking third in density among the autosomes4. Here we report a finished sequence for human chromosome 17, as well as a structural comparison with the finished sequence for mouse chromosome 11, the first finished mouse chromosome. Comparison of the orthologous regions reveals striking differences. In contrast to the typical pattern seen in mammalian evolution5,6, the human sequence has undergone extensive intrachromosomal rearrangement, whereas the mouse sequence has been remarkably stable. Moreover, although the human sequence has a high density of segmental duplication, the mouse sequence has a very low density. Notably, these segmental duplications correspond closely to the sites of structural rearrangement, demonstrating a link between duplication and rearrangement. Examination of the main classes of duplicated segments provides insight into the dynamics underlying expansion of chromosome-specific, low-copy repeats in the human genome.
doi:10.1038/nature04689
PMCID: PMC2610434  PMID: 16625196
15.  Petabyte-scale innovations at the European Nucleotide Archive 
Nucleic Acids Research  2008;37(Database issue):D19-D25.
Dramatic increases in the throughput of nucleotide sequencing machines, and the promise of ever greater performance, have thrust bioinformatics into the era of petabyte-scale data sets. Sequence repositories, which provide the feed for these data sets into the worldwide computational infrastructure, are challenged by the impact of these data volumes. The European Nucleotide Archive (ENA; http://www.ebi.ac.uk/embl), comprising the EMBL Nucleotide Sequence Database and the Ensembl Trace Archive, has identified challenges in the storage, movement, analysis, interpretation and visualization of petabyte-scale data sets. We present here our new repository for next generation sequence data, a brief summary of contents of the ENA and provide details of major developments to submission pipelines, high-throughput rule-based validation infrastructure and data integration approaches.
doi:10.1093/nar/gkn765
PMCID: PMC2686451  PMID: 18978013
16.  Severely Mentally Ill Women’s HIV Risk: The Influence of Social Support, Substance Use, and Contextual Risk Factors 
In structured interviews with 96 women with severe mental illness, nearly two-thirds had not used condoms during sexual intercourse in the past 3 months, more than two-thirds had sex with multiple partners, and almost one-third had been treated for a sexually transmitted infection (STI) in the past year. Women who reported fewer sexual risk context factors, such as having sex with someone the participant did not know or transactional sex, had fewer sexual partners. Larger social support networks were associated with less frequent sex after drug use. In turn, women who less often had sex after using drugs had unprotected intercourse less frequently.
doi:10.1007/s10597-006-9069-0
PMCID: PMC2410084  PMID: 17143730
sexual risk behavior; HIV/AIDS; serious mental illness; women’s health
17.  Variation analysis and gene annotation of eight MHC haplotypes: The MHC Haplotype Project 
Immunogenetics  2008;60(1):1-18.
The human major histocompatibility complex (MHC) is contained within about 4 Mb on the short arm of chromosome 6 and is recognised as the most variable region in the human genome. The primary aim of the MHC Haplotype Project was to provide a comprehensively annotated reference sequence of a single, human leukocyte antigen-homozygous MHC haplotype and to use it as a basis against which variations could be assessed from seven other similarly homozygous cell lines, representative of the most common MHC haplotypes in the European population. Comparison of the haplotype sequences, including four haplotypes not previously analysed, resulted in the identification of >44,000 variations, both substitutions and indels (insertions and deletions), which have been submitted to the dbSNP database. The gene annotation uncovered haplotype-specific differences and confirmed the presence of more than 300 loci, including over 160 protein-coding genes. Combined analysis of the variation and annotation datasets revealed 122 gene loci with coding substitutions of which 97 were non-synonymous. The haplotype (A3-B7-DR15; PGF cell line) designated as the new MHC reference sequence, has been incorporated into the human genome assembly (NCBI35 and subsequent builds), and constitutes the largest single-haplotype sequence of the human genome to date. The extensive variation and annotation data derived from the analysis of seven further haplotypes have been made publicly available and provide a framework and resource for future association studies of all MHC-associated diseases and transplant medicine.
doi:10.1007/s00251-007-0262-2
PMCID: PMC2206249  PMID: 18193213
Major histocompatibility complex; Haplotype; Polymorphism; Retroelement; Genetic predisposition to disease; Population genetics
18.  Continence promotion for older hospital patients following surgery for fractured neck of femur: Pilot of a randomized controlled trial 
Clinical Interventions in Aging  2007;2(4):705-714.
Evidence suggests that bladder control problems develop or worsen as a result of fractured neck of femur (#NOF) and its subsequent management.
The primary aim of this study was to reduce the prevalence and severity of post surgery continence problems among patients, aged from 60-years, undergoing surgery for #NOF, using a best practice “case-management model” multifactorial intervention.
Eligible consenting patients admitted with #NOF were randomized to intervention or control group. Self-report questionnaires compared pre-surgery, post surgery, and follow-up continence status between groups.
This pilot randomized controlled trial, which included 45 eligible patients aged 60 to 93-years, found no evidence that the intervention was effective in reducing prevalence of post-surgery incontinence in this acute setting. Staff surveys highlighted the need for open communication between the research team and hospital staff. Unclear results were attributed to the small sample size.
A central outcome was evidence that intervention to improve continence management for older people post-surgery is imperative. Focused assessment and treatment for those most at risk of incontinence after #NOF would be more acceptable to staff and a more efficient use of resources. A simple screening tool would ensure that those most at risk are detected, and targeted for care.
PMCID: PMC2686329  PMID: 18225472
urinary incontinence; prevention; management; fractured neck of femur; hip surgery; randomized controlled trial; elderly
19.  A stochastic model for circadian rhythms from coupled ultradian oscillators 
Background
Circadian rhythms with varying components exist in organisms ranging from humans to cyanobacteria. A simple evolutionarily plausible mechanism for the origin of such a variety of circadian oscillators, proposed in earlier work, involves the non-disruptive coupling of pre-existing ultradian transcriptional-translational oscillators (TTOs), producing "beats," in individual cells. However, like other TTO models of circadian rhythms, it is important to establish that the inherent stochasticity of the protein binding and unbinding does not invalidate the finding of clear oscillations with circadian period.
Results
The TTOs of our model are described in two versions: 1) a version in which the activation or inhibition of genes is regulated stochastically, where the 'unoccupied" (or "free") time of the site under consideration depends on the concentration of a protein complex produced by another site, and 2) a deterministic, "time-averaged" version in which the switching between the "free" and "occupied" states of the sites occurs so rapidly that the stochastic effects average out. The second case is proved to emerge from the first in a mathematically rigorous way. Numerical results for both scenarios are presented and compared.
Conclusion
Our model proves to be robust to the stochasticity of protein binding/unbinding at experimentally determined rates and even at rates several orders of magnitude slower. We have not only confirmed this by numerical simulation, but have shown in a mathematically rigorous way that the time-averaged deterministic system is indeed the fast-binding-rate limit of the full stochastic model.
doi:10.1186/1742-4682-4-1
PMCID: PMC1794229  PMID: 17212831
20.  Considerations Regarding the Implementation of Computerized Physician Order Entry: Report of the Menucha Conference 
Implementation of computerized physician order entry (POE) is being increasingly encouraged as an important solution to the challenge of medical error reduction. Use of POE is not widespread, however, in part because it has a reputation for being difficult to implement. To identify success factors for implementing POE, a consensus conference of invited experts holding multiple perspectives was convened near Portland, Oregon on May 10 and 11, 2001. At a retreat center called Menucha, experts from around the world met with members of the Oregon Health & Science University's Physician Order Entry Team (POET) of researchers for the purpose of developing recommendations for POE implementation. Funded by a research grant from the National Library of Medicine, the Menucha consensus conference succeeded in identifying a set of conditions that should exist prior to POE implementation, agreed on considerations for successful implementation, and a list of other considerations that fostered debate within the group and deserve further exploration.
PMCID: PMC2243453

Results 1-20 (20)