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Challenges with engaging participants in behavioral intervention research trials
David Olem,Kelly M Sharp,Mallory O Johnson
Open Access Journal of Clinical Trials , 2009,
Abstract: David Olem, Kelly M Sharp, Mallory O JohnsonDepartment of Medicine, University of California, San Francisco, CA, USAAbstract: In clinical trials research, nonadherence to an investigational health promotion intervention poses threats to internal validity, thus raising concern over the trial outcomes and interpretation of results. Successfully helping participants to engage in and complete a multisession intervention can be particularly challenging. This task can become more complicated when working with participants who are dealing with chronic health conditions and are from diverse cultural, socio-economic, and marginalized backgrounds who may have competing needs, beliefs, and priorities that conflict with the needs of the trial protocols. This paper identifies some of the challenges to helping individuals participate in the sessions of a behavioral intervention and shares a set of strategies developed by a clinical research team to engage with participants and minimize barriers to completing the intervention.Keywords: clinical trials, behavioral interventions, retention, internal validity
Prevalence and Incidence of HIV Infection among Fishermen along Lake Victoria Beaches in Kisumu County, Kenya  [PDF]
Raphael Omusebe Ondondo, Zipporah Waithera Ng’ang’a, Solomon Mpoke, Michael Kiptoo, Elizabeth A. Bukusi
World Journal of AIDS (WJA) , 2014, DOI: 10.4236/wja.2014.42027
Abstract:

Background: Herpes simplex virus type-2 (HSV-2) and human papillomavirus (HPV) are common sexually transmitted infections (STIs) among fishing communities and are associated with high HIV prevalence in this underserved population. However, there is limited knowledge on HIV incidence among fishermen. This study aimed at determining prevalence, incidence and risk factors associated with HIV infection among fishermen in Kisumu Kenya. Methods: Three hundred fishermen were evaluated for baseline HIV, HSV-2, HPV infection and a structured questionnaire administered. HIV incidence was assessed after 12 months among those initially HIV negative. HIV incidence rate in person-years and prevalence were estimated. Multivariate logistic regression was used to determine factors independently associated with HIV acquisition. Results: HIV prevalence was 23.3% (95% CI: 18.5 - 28.1). Risk factors for baseline HIV prevalence were older age (aOR = 2.13; 95% CI: 1.25 - 5.07), history of STI (aOR 4.21; 95% CI: 2.07 - 9.34), baseline HPV infection (aOR 2.13; 95% CI: 1.05 - 4.77), number of lifetime sexual partners (>5) aOR = 5.76 (95% CI: 1.41 - 13.57) and transactional sex (aOR = 10.98; 95% CI: 1.86 - 19.34). Condom uses with new sexual partner (aOR 0.21, 95% CI: 0.08 - 0.55) and during most recent sexual act (aOR 0.09, 95% CI: 0.03 - 0.61), were negatively associated with HIV prevalence. HIV incidence was 4.2 (95% CI = 1.3 - 7.1) per 100 person-years with being single (aIRR = 8.32; 95% CI: 1.27 - 54.67) as an independent risk factor. Condom use with new sexual partner (aIRR = 0.11; 95% CI: 0.01 - 0.89) and recent sex with wife/regular girlfriend (compared to sex worker/casual partner; aIRR = 0.03; 95% CI: 0.01 - 0.35) were associated with reduced risk of HIV acquisition. Conclusion: Inconsistent condom use and transactional/casual sexual partnerships were the main high-risk sexual behaviors in addition to marital status explaining the high HIV acquisition rate among fishermen. Intensified safer sex promotion is urgently needed in this subpopulation to avert new HIV infections.

Challenges with engaging participants in behavioral intervention research trials
David Olem, Kelly M Sharp, Mallory O Johnson
Open Access Journal of Clinical Trials , 2009, DOI: http://dx.doi.org/10.2147/OAJCT.S6841
Abstract: llenges with engaging participants in behavioral intervention research trials Short Report (5079) Total Article Views Authors: David Olem, Kelly M Sharp, Mallory O Johnson Published Date November 2009 Volume 2009:1(Default) Pages 17 - 21 DOI: http://dx.doi.org/10.2147/OAJCT.S6841 David Olem, Kelly M Sharp, Mallory O Johnson Department of Medicine, University of California, San Francisco, CA, USA Abstract: In clinical trials research, nonadherence to an investigational health promotion intervention poses threats to internal validity, thus raising concern over the trial outcomes and interpretation of results. Successfully helping participants to engage in and complete a multisession intervention can be particularly challenging. This task can become more complicated when working with participants who are dealing with chronic health conditions and are from diverse cultural, socio-economic, and marginalized backgrounds who may have competing needs, beliefs, and priorities that conflict with the needs of the trial protocols. This paper identifies some of the challenges to helping individuals participate in the sessions of a behavioral intervention and shares a set of strategies developed by a clinical research team to engage with participants and minimize barriers to completing the intervention.
Estimation of HIV Incidence in a Large, Community-Based, Randomized Clinical Trial: NIMH Project Accept (HIV Prevention Trials Network 043)  [PDF]
Oliver Laeyendecker, Estelle Piwowar-Manning, Agnes Fiamma, Michal Kulich, Deborah Donnell, Deb Bassuk, Caroline E. Mullis, Craig Chin, Priscilla Swanson, John Hackett, William Clarke, Mark Marzinke, Greg Szekeres, Glenda Gray, Linda Richter, Michel W. Alexandre, Suwat Chariyalertsak, Alfred Chingono, David D. Celentano, Stephen F. Morin, Michael Sweat, Thomas Coates, Susan H. Eshleman
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0068349
Abstract: Background National Institute of Mental Health Project Accept (HIV Prevention Trials Network [HPTN] 043) is a large, Phase III, community-randomized, HIV prevention trial conducted in 48 matched communities in Africa and Thailand. The study intervention included enhanced community-based voluntary counseling and testing. The primary endpoint was HIV incidence, assessed in a single, cross-sectional, post-intervention survey of >50,000 participants. Methods HIV rapid tests were performed in-country. HIV status was confirmed at a central laboratory in the United States. HIV incidence was estimated using a multi-assay algorithm (MAA) that included the BED capture immunoassay, an avidity assay, CD4 cell count, and HIV viral load. Results Data from Thailand was not used in the endpoint analysis because HIV prevalence was low. Overall, 7,361 HIV infections were identified (4 acute, 3 early, and 7,354 established infections). Samples from established infections were analyzed using the MAA; 467 MAA positive samples were identified; 29 of those samples were excluded because they contained antiretroviral drugs. HIV prevalence was 16.5% (range at study sites: 5.93% to 30.8%). HIV incidence was 1.60% (range at study sites: 0.78% to 3.90%). Conclusions In this community-randomized trial, a MAA was used to estimate HIV incidence in a single, cross-sectional post-intervention survey. Results from this analysis were subsequently used to compare HIV incidence in the control and intervention communities. Trial Registration ClinicalTrials.gov NCT00203749
Statistical Methods in Recent HIV Noninferiority Trials: Reanalysis of 11 Trials  [PDF]
Philippe Flandre
PLOS ONE , 2011, DOI: 10.1371/journal.pone.0022871
Abstract: Background In recent years the “noninferiority” trial has emerged as the new standard design for HIV drug development among antiretroviral patients often with a primary endpoint based on the difference in success rates between the two treatment groups. Different statistical methods have been introduced to provide confidence intervals for that difference. The main objective is to investigate whether the choice of the statistical method changes the conclusion of the trials. Methods We presented 11 trials published in 2010 using a difference in proportions as the primary endpoint. In these trials, 5 different statistical methods have been used to estimate such confidence intervals. The five methods are described and applied to data from the 11 trials. The noninferiority of the new treatment is not demonstrated if the prespecified noninferiority margin it includes in the confidence interval of the treatment difference. Results Results indicated that confidence intervals can be quite different according to the method used. In many situations, however, conclusions of the trials are not altered because point estimates of the treatment difference were too far from the prespecified noninferiority margins. Nevertheless, in few trials the use of different statistical methods led to different conclusions. In particular the use of “exact” methods can be very confusing. Conclusion Statistical methods used to estimate confidence intervals in noninferiority trials have a strong impact on the conclusion of such trials.
Retroviral integration: A critical step in viral life cycle suitable for drug intervention
Fernández-Ortega,Celia; Ramírez-Suárez,Anna; Paneque-Guerrero,Taimi; Casillas-Casanova,Dionne;
Biotecnolog?-a Aplicada , 2011,
Abstract: retroviral integration is an essential stage in the life cycle of retroviruses. viruses need to insert their dna into the chromosomal dna of the host cells. retroviral integration is a complex process which involves viral and host proteins and requires the movement of the retroviral dna from the cytoplasm to the nucleus. the viral integrase is a key enzyme in this process that catalyzes two reactions: 3′ processing of viral dna that take place in the cytoplasm following reverse transcription and the strand transfer that inserts viral dna in a host cell chromosome. development of a successful treatment for the human immunodeficiency virus (hiv) infection using the strand transfer inhibitor, raltegravir, has demonstrated that retroviral integration is a suitable step for drug intervention. different types of inhibitors targeting hiv integrase or any of the other components of the retroviral integration process are currently being designed or developed. this work contains a summary of the retroviral integration process as well as, many of the latest advances in this topic which were exposed at the recently held ivth international meeting on retroviral integration.
Community-based trials of sexually transmitted disease treatment: repercussions for epidemiology and HIV prevention
Hudson,Christopher P.;
Bulletin of the World Health Organization , 2001, DOI: 10.1590/S0042-96862001000100010
Abstract: this paper reviews the scientific basis for trials exploring the relation between sexually transmitted diseases (stds) and human immunodeficiency virus (hiv) infection in mwanza in the united republic of tanzania and rakai and masaka in the republic of uganda. the importance of a study?s location and explanations for the divergent results of these trials are discussed. the modest effect on stds seen in the trial of syndromic management in mwanza, in contrast to the 38% reduction in the incidence of hiv, casts doubt on the underlying hypothesis that treating stds alone slows the transmission of hiv-1. according to the piot-fransen model, the trial in rakai, which offered treatment of stds to all subjects irrespective of symptoms (??mass?? treatment), should have been more effective both in reducing the prevalence of stds and the incidence of hiv. however, the rakai trial was stopped because there was no difference in the incidence of hiv between the intervention and control arms. if mwanza is seen as the trial that needs explaining, another paradigm becomes relevant. in rural east africa, where all trials have been conducted, networks of concurrent sexual partnerships are a source of infection with both stds and hiv. because of their shorter latency periods, stds may prompt attendance at a clinic before the early signs of hiv-1 infection appear. part of the management of stds is to recommend abstinence or the consistent use of condoms until treatment is completed. this recommendation may cover the earliest period of viraemia during primary hiv-1 infection. this paradigm appears to explain the results from mwanza and rakai, emphasizing behavioural aspects of syndromic management.
Community-based trials of sexually transmitted disease treatment: repercussions for epidemiology and HIV prevention  [cached]
Hudson Christopher P.
Bulletin of the World Health Organization , 2001,
Abstract: This paper reviews the scientific basis for trials exploring the relation between sexually transmitted diseases (STDs) and human immunodeficiency virus (HIV) infection in Mwanza in the United Republic of Tanzania and Rakai and Masaka in the Republic of Uganda. The importance of a study?s location and explanations for the divergent results of these trials are discussed. The modest effect on STDs seen in the trial of syndromic management in Mwanza, in contrast to the 38% reduction in the incidence of HIV, casts doubt on the underlying hypothesis that treating STDs alone slows the transmission of HIV-1. According to the Piot-Fransen model, the trial in Rakai, which offered treatment of STDs to all subjects irrespective of symptoms (??mass?? treatment), should have been more effective both in reducing the prevalence of STDs and the incidence of HIV. However, the Rakai trial was stopped because there was no difference in the incidence of HIV between the intervention and control arms. If Mwanza is seen as the trial that needs explaining, another paradigm becomes relevant. In rural East Africa, where all trials have been conducted, networks of concurrent sexual partnerships are a source of infection with both STDs and HIV. Because of their shorter latency periods, STDs may prompt attendance at a clinic before the early signs of HIV-1 infection appear. Part of the management of STDs is to recommend abstinence or the consistent use of condoms until treatment is completed. This recommendation may cover the earliest period of viraemia during primary HIV-1 infection. This paradigm appears to explain the results from Mwanza and Rakai, emphasizing behavioural aspects of syndromic management.
Are Women Who Work in Bars, Guesthouses and Similar Facilities a Suitable Study Population for Vaginal Microbicide Trials in Africa?  [PDF]
Andrew Vallely,Ian R. Hambleton,Stella Kasindi,Louise Knight,Suzanna C. Francis,Tobias Chirwa,Dean Everett,Charles Shagi,Claire Cook,Celia Barberousse,Deborah Watson-Jones,John Changalucha,David Ross,Richard J. Hayes
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0010661
Abstract: A feasibility study was conducted to investigate whether an occupational at-risk cohort of women in Mwanza, Tanzania are a suitable study population for future phase III vaginal microbicide trials.
The Characterization of Obese Polycystic Ovary Syndrome Rat Model Suitable for Exercise Intervention  [PDF]
Chuyan Wu, Feng Lin, Shuwei Qiu, Zhongli Jiang
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0099155
Abstract: Objective To develop a new polycystic ovary syndrome (PCOS) rat model suitable for exercise intervention. Method Thirty six rats were randomly divided into three experimental groups: PCOS rats with high-fat diet (PF, n = 24), PCOS rats with ordinary diet (PO, n = 6), and control rats with ordinary diet (CO, n = 6). Two kinds of PCOS rat model were made by adjustment diet structure and testosterone injection for 28 days. After a successful animal model, PF model rats were randomly assigned to three groups: exercise with a continuation of high-fat diet (PF-EF, n = 6), sedentary with a continuation of high-fat diet (PF-SF, n = 6), exercise with an ordinary diet (PF-EO, n = 6). Fasting blood glucose (FBG) and insulin (FINS), estrogen (E2), progesterone (P), and testosterone (T) in serum were determined by RIA, and ovarian morphology was evaluated by Image-Pro plus 6.0. Results Body weight, Lee index, FINS increased significantly in PF rat model. Serum levels of E2 and T were significantly higher in PF and PO than in CO. Ovary organ index and ovarian areas were significant lower in PF than in CO. After intervention for 2 weeks, the levels of 1 h postprandial blood glucose (PBG1), 2 h postprandial blood glucose (PBG2), FINS and the serum levels of T decreased significantly in PF-EF rats and PF-EO rats. The ratio of FBG/FINS was significant higher in PF-EO rats than in PF-SF rats. Ovarian morphology showed that the numbers of preantral follicles and atretic follicles decreased significantly, and the numbers of antral follicles and corpora lutea increased significantly in the rats of PF-EF and PF-EO. Conclusion By combination of high-fat diet and testosterone injection, the obese PCOS rat model is conformable with the lifestyle habits of fatty foods and insufficient exercise, and has metabolic and reproductive characteristics of human PCOS. This model can be applied to study exercise intervention.
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