30 results on '"Wong VJ"'
Search Results
2. Social network strategy (SNS) for HIV testing: a new approach for identifying individuals with undiagnosed HIV infection in Tanzania.
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Rwabiyago OE, Katale A, Bingham T, Grund JM, Machangu O, Medley A, Nkomela ZM, Kayange A, King'ori GN, Juma JM, Ismail A, Kategile U, Akom E, Mlole NT, Schaad N, Maokola W, Nyagonde N, Magesa D, Kazitanga JC, Maruyama H, Temu F, Kimambo S, Sando D, Mbatia R, Chalamila ST, Ogwang BE, Njelekela MA, Kazaura K, Wong VJ, Gongo R, Njau PF, Mbunda A, Nondi J, Bateganya M, Greene J, Breda M, Mgomella G, Rwebembera A, and Swaminathan M
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- Humans, Tanzania epidemiology, Female, Male, Adult, Adolescent, Young Adult, Middle Aged, Mass Screening methods, Social Support, Child, HIV Infections diagnosis, HIV Infections epidemiology, HIV Testing methods, Social Networking
- Abstract
Social network strategy (SNS) testing uses network connections to refer individuals at high risk to HIV testing services (HTS). In Tanzania, SNS testing is offered in communities and health facilities. In communities, SNS testing targets key and vulnerable populations (KVP), while in health facilities it complements index testing by reaching unelicited index contacts. Routine data were used to assess performance and trends over time in PEPFAR-supported sites between October 2021 and March 2023. Key indicators included SNS social contacts tested, and new HIV-positives individuals identified. Descriptive and statistical analysis were conducted. Univariable and multivariable analysis were applied, and variables with P -values <0.2 at univariable analysis were considered for multivariable analysis. Overall, 121,739 SNS contacts were tested, and 7731 (6.4%) previously undiagnosed individuals living with HIV were identified. Tested contacts and identified HIV-positives were mostly aged ≥15 years (>99.7%) and females (80.6% of tests, 79.4% of HIV-positives). Most SNS contacts were tested (78,363; 64.7%) and diagnosed (6376; 82.5%) in communities. SNS tests and HIV-positives grew 11.5 and 6.1-fold respectively, from October-December 2021 to January-March 2023, with majority of clients reached in communities vs. facilities (78,763 vs. 42,976). These results indicate that SNS testing is a promising HIV case-finding approach in Tanzania.
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- 2024
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3. Facility HIV Self-Testing in Outpatient Departments: An Assessment of Characteristics and Concerns of Outpatients Who Opt Out of Testing in Malawi.
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Shaba F, Balakasi KT, Offorjebe OA, Nyirenda M, Wong VJ, Gupta SK, Hoffman RM, and Dovel K
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- Adult, Humans, Male, HIV, Outpatients, Self-Testing, Malawi epidemiology, HIV Testing, Mass Screening, HIV Infections diagnosis, HIV Infections epidemiology
- Abstract
Background: Facility HIV self-testing (HIVST) in outpatient departments can dramatically increase testing among adult outpatients. However, it is still unclear why populations opt out of facility HIVST and reasons for opt outing. Using data from a parent facility HIVST trial, we sought to understand individual characteristics associated with opting out of facility HIVST and reported reasons for not testing., Methods: Exit surveys were conducted with outpatients aged ≥15 years at 5 facilities in Central and Southern Malawi randomized to the facility HIVST arm of the parent trial. Outpatients were eligible for our substudy if they were offered HIVST and eligible for HIV testing (ie, never previously tested HIV positive and tested ≥12 months ago or never tested). Summary statistics and multivariate regression models were used., Results: Seven hundred seventy-one outpatients were included in the substudy. Two hundred sixty-three (34%) opted out of HIVST. Urban residency (adjusted risk ratios [aRR] 3.48; 95% CI: 1.56 to 7.76) and self-reported poor health (aRR 1.86; 95% CI: 1.27 to 2.72) were associated with an increased risk of opting out. Male participants had a 69% higher risk of opting out (aRR 1.69; 95% CI: 1.14 to 2.51), with risk being 38% lower among working male participants. Primary reasons for not testing were feeling unprepared to test (49·4%) and perceived low risk of HIV infection (30·4%)-only 2.6% believed that HIVST instructions were unclear, and 1.7% were concerned about privacy., Conclusion: Working, risky sexual behavior, rural residence, and good self-rated health were positively associated with opting out of HIVST among outpatients. Strategies to address internalized barriers, such as preparedness to test and perceived need to test, should be incorporated into facility HIVST interventions., Competing Interests: The authors have no conflicts of interest to disclose., (Copyright © 2023 The Author(s). Published by Wolters Kluwer Health, Inc.)
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- 2024
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4. Demand creation for HIV testing services: A systematic review and meta-analysis.
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Wagner AD, Njuguna IN, Neary J, Lawley KA, Louden DKN, Tiwari R, Jiang W, Kalu N, Burke RM, Mangale D, Obermeyer C, Escudero JN, Bulterys MA, Waters C, Mollo B, Han H, Barr-DiChiara M, Baggaley R, Jamil MS, Shah P, Wong VJ, Drake AL, and Johnson CC
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- Humans, Americas, HIV Testing, HIV Infections diagnosis, HIV Infections epidemiology
- Abstract
Background: HIV testing services (HTS) are the first steps in reaching the UNAIDS 95-95-95 goals to achieve and maintain low HIV incidence. Evaluating the effectiveness of different demand creation interventions to increase uptake of efficient and effective HTS is useful to prioritize limited programmatic resources. This review was undertaken to inform World Health Organization (WHO) 2019 HIV testing guidelines and assessed the research question, "Which demand creation strategies are effective for enhancing uptake of HTS?" focused on populations globally., Methods and Findings: The following electronic databases were searched through September 28, 2021: PubMed, PsycInfo, Cochrane CENTRAL, CINAHL Complete, Web of Science Core Collection, EMBASE, and Global Health Database; we searched IAS and AIDS conferences. We systematically searched for randomized controlled trials (RCTs) that compared any demand creation intervention (incentives, mobilization, counseling, tailoring, and digital interventions) to either a control or other demand creation intervention and reported HTS uptake. We pooled trials to evaluate categories of demand creation interventions using random-effects models for meta-analysis and assessed study quality with Cochrane's risk of bias 1 tool. This study was funded by the WHO and registered in Prospero with ID CRD42022296947. We screened 10,583 records and 507 conference abstracts, reviewed 952 full texts, and included 124 RCTs for data extraction. The majority of studies were from the African (N = 53) and Americas (N = 54) regions. We found that mobilization (relative risk [RR]: 2.01, 95% confidence interval [CI]: [1.30, 3.09], p < 0.05; risk difference [RD]: 0.29, 95% CI [0.16, 0.43], p < 0.05, N = 4 RCTs), couple-oriented counseling (RR: 1.98, 95% CI [1.02, 3.86], p < 0.05; RD: 0.12, 95% CI [0.03, 0.21], p < 0.05, N = 4 RCTs), peer-led interventions (RR: 1.57, 95% CI [1.15, 2.15], p < 0.05; RD: 0.18, 95% CI [0.06, 0.31], p < 0.05, N = 10 RCTs), motivation-oriented counseling (RR: 1.53, 95% CI [1.07, 2.20], p < 0.05; RD: 0.17, 95% CI [0.00, 0.34], p < 0.05, N = 4 RCTs), short message service (SMS) (RR: 1.53, 95% CI [1.09, 2.16], p < 0.05; RD: 0.11, 95% CI [0.03, 0.19], p < 0.05, N = 5 RCTs), and conditional fixed value incentives (RR: 1.52, 95% CI [1.21, 1.91], p < 0.05; RD: 0.15, 95% CI [0.07, 0.22], p < 0.05, N = 11 RCTs) all significantly and importantly (≥50% relative increase) increased HTS uptake and had medium risk of bias. Lottery-based incentives and audio-based interventions less importantly (25% to 49% increase) but not significantly increased HTS uptake (medium risk of bias). Personal invitation letters and personalized message content significantly but not importantly (<25% increase) increased HTS uptake (medium risk of bias). Reduced duration counseling had comparable performance to standard duration counseling (low risk of bias) and video-based interventions were comparable or better than in-person counseling (medium risk of bias). Heterogeneity of effect among pooled studies was high. This study was limited in that we restricted to randomized trials, which may be systematically less readily available for key populations; additionally, we compare only pooled estimates for interventions with multiple studies rather than single study estimates, and there was evidence of publication bias for several interventions., Conclusions: Mobilization, couple- and motivation-oriented counseling, peer-led interventions, conditional fixed value incentives, and SMS are high-impact demand creation interventions and should be prioritized for programmatic consideration. Reduced duration counseling and video-based interventions are an efficient and effective alternative to address staffing shortages. Investment in demand creation activities should prioritize those with undiagnosed HIV or ongoing HIV exposure. Selection of demand creation interventions must consider risks and benefits, context-specific factors, feasibility and sustainability, country ownership, and universal health coverage across disease areas., Competing Interests: The authors have declared that no competing interests exist., (Copyright: This is an open access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.)
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- 2023
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5. The HIV Pandemic Prevention Efforts Can Inform the COVID-19 Pandemic Response in the United States.
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Carrasco MA, Atkins K, Young R, Rosen JG, Grieb SM, Wong VJ, and Fleming PJ
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- Communication, Humans, Pandemics prevention & control, Risk Factors, United States epidemiology, COVID-19 epidemiology, COVID-19 transmission, COVID-19 Testing, Disease Transmission, Infectious prevention & control, HIV Infections epidemiology
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- 2021
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6. Addressing Intimate Partner Violence and Power in Intimate Relationships in HIV Testing Services in Nairobi, Kenya.
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Haberland N, Ndwiga C, McCarthy K, Pulerwitz J, Kosgei R, Mak'anyengo M, Peltz A, Wong VJ, and Kalibala S
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- Adolescent, Adult, Female, Humans, Infectious Disease Transmission, Vertical, Kenya epidemiology, Middle Aged, Pregnancy, Sexual Partners, Young Adult, HIV Infections diagnosis, HIV Infections prevention & control, HIV Infections transmission, Intimate Partner Violence prevention & control
- Abstract
Intimate partner violence (IPV) undermines women's uptake of HIV services and violates their human rights. In a two-arm randomized controlled trial we evaluated a short intervention that went a step beyond IPV screening to discuss violence and power with women receiving HIV testing services during antenatal care (ANC). The intervention included training and support for HIV counselors, a take-home card for clients, and an on-site IPV counselor. One third (35%) of women (N = 688) reported experiencing IPV in the past year; 6% were living with HIV. Among women experiencing IPV, program participants were more likely to disclose violence to their counselor than women receiving standard care (32% vs. 7%, p < 0.001). At second ANC visit, intervention group women were significantly more likely to report that talking with their counselor made a positive difference (aOR 2.9; 95% CI 1.8, 4.4; p < 0.001) and felt more confident in how they deserved to be treated (aOR 2.7; 95% CI 1.7, 4.4; p < 0.001). Exploratory analyses of intent to use ARVs to prevent mother-to-child transmission and actions to address violence were also encouraging.
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- 2020
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7. Use and awareness of and willingness to self-test for HIV: an analysis of cross-sectional population-based surveys in Malawi and Zimbabwe.
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Johnson C, Neuman M, MacPherson P, Choko A, Quinn C, Wong VJ, Hatzold K, Nyrienda R, Ncube G, Baggaley R, Terris-Prestholt F, and Corbett EL
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- Adolescent, Adult, Cross-Sectional Studies, Female, HIV Infections epidemiology, Humans, Malawi epidemiology, Male, Middle Aged, Young Adult, Zimbabwe epidemiology, HIV Infections diagnosis, Health Knowledge, Attitudes, Practice, Mass Screening methods, Self Care psychology, Self Care statistics & numerical data
- Abstract
Background: Many southern African countries are nearing the global goal of diagnosing 90% of people with HIV by 2020. In 2016, 84 and 86% of people with HIV knew their status in Malawi and Zimbabwe, respectively. However, gaps remain, particularly among men. We investigated awareness and use of, and willingness to self-test for HIV and explored sociodemographic associations before large-scale implementation., Methods: We pooled responses from two of the first cross-sectional Demographic and Health Surveys to include HIV self-testing (HIVST) questions in Malawi and Zimbabwe in 2015-16. We investigated sociodemographic factors and sexual risk behaviours associated with previously testing for HIV, and past use, awareness of, and future willingness to self-test using univariable and multivariable logistic regression, adjusting for the sample design and limiting analysis to participants with a completed questionnaire and valid HIV test result. We restricted analysis of willingness to self-test to Zimbabwean men, as women and Malawians were not systematically asked this question., Results: Of 31,385 individuals, 31.2% of men had never tested compared with 16.5% of women (p < 0.001). For men, the likelihood of having ever tested increased with age. Past use and awareness of HIVST was very low, 1.2 and 12.6%, respectively. Awareness was lower among women than men (9.1% vs 15.3%, adjusted odds ratio [aOR] = 1.55; 95% confidence interval [CI]: 1.37-1.75), and at younger ages, and lower education and literacy levels. Willingness to self-test among Zimbabwean men was high (84.5%), with greater willingness associated with having previously tested for HIV, being at high sexual risk (highest willingness [aOR = 3.74; 95%CI: 1.39-10.03, p < 0.009]), and being ≥25 years old. Wealthier men had greater awareness of HIVST than poorer men (p < 0.001). The highest willingness to self-test (aOR = 3.74; 95%CI: 1.39-10.03, p < 0.009) was among men at high HIV-related sexual risk., Conclusions: In 2015-16, many Malawian and Zimbabwean men had never tested for HIV. Despite low awareness and minimal HIVST experience, willingness to self-test was high among Zimbabwean men, especially older men with moderate-to-high HIV-related sexual risk. These data provide a valuable baseline against which to investigate population-level uptake of HIVST as programmes scale up. Programmes introducing, or planning to introduce, HIVST should consider including relevant questions in population-based surveys.
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- 2020
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8. Antibiotic prophylaxis after urethroplasty may offer no benefit.
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Manjunath A, Chen L, Welty LJ, Wong VJ, Amarasekera C, Gonzalez CM, and Hofer MD
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- Adult, Humans, Male, Middle Aged, Retrospective Studies, Treatment Failure, Urologic Surgical Procedures, Male methods, Antibiotic Prophylaxis, Urethra surgery, Urethral Stricture surgery, Urinary Tract Infections prevention & control
- Abstract
Purpose: Patients often receive antibiotic prophylaxis after urethroplasty to minimize the risk of urinary tract infection (UTI). The aim of this study was to determine the frequency of UTIs after urethroplasty and its impact on urethral and incisional healing., Methods: Patients undergoing urethroplasty by a single surgeon from 2000 to 2012 were retrospectively reviewed. All patients received preoperative antibiotic prophylaxis and postoperative prophylaxis for 30 days or until catheter removal. We reviewed urine cultures obtained within 30 days after urethroplasty in symptomatic patients, and rates of stricture recurrence and wound complications. A positive culture was defined as > 1000 cfu/mL of an organism., Results: 398 patients were included with a mean age of 43.5 years at time of surgery. We identified 102 positive urine cultures (25.6%) within 30 days of urethroplasty. 78 stricture recurrences (19.6%) occurred at an average of 3 years after surgery and 18 (4.5%) experienced a wound complication, with a 52 month mean follow-up. There were no significant differences in stricture recurrence (p = 0.36) or wound complications (p = 0.42) between patients who had a positive and negative urine culture. On multivariate analysis, positive urine cultures (HR 1.0, 95% CI 0.6-1.8, p = 0.88) were not associated with stricture recurrence, while lichen sclerosis (HR 3.2, 95% CI 1.1-9.2, p = 0.03) and previous urethroplasty (HR 2.3, 95% CI 1.1-4.6, p = 0.03) were., Conclusion: Bacterial colonization and UTIs despite antimicrobial prophylaxis are common in urethroplasty patients. This, however, does not appear to impair urethral healing or influence wound healing, suggesting that postoperative prophylaxis may in fact offer no benefit.
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- 2020
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9. Use and Acceptability of HIV Self-Testing Among First-Time Testers at Risk for HIV in Senegal.
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Lyons CE, Coly K, Bowring AL, Liestman B, Diouf D, Wong VJ, Turpin G, Castor D, Dieng P, Olawore O, Geibel S, Ketende S, Ndour C, Thiam S, Touré-Kane C, and Baral SD
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- Adult, Diagnostic Self Evaluation, Female, HIV Infections epidemiology, Humans, Male, Mass Screening methods, Pilot Projects, Senegal, Serologic Tests, Sexual Behavior, Social Stigma, Surveys and Questionnaires, HIV Infections diagnosis, Mass Screening statistics & numerical data, Reagent Kits, Diagnostic, Sex Workers statistics & numerical data, Sexual and Gender Minorities statistics & numerical data
- Abstract
HIV Self-Testing (HIVST) aims to increase HIV testing coverage and can facilitate reaching the UNAIDS 90-90-90 targets. In Senegal, key populations bear a disproportionate burden of HIV and report limited uptake of HIV testing given pervasive stigma and criminalization. In these contexts, HIVST may represent a complementary approach to reach populations reporting barriers to engagement with existing and routine HIV testing services. In this study, 1839 HIVST kits were distributed in Senegal, with 1149 individuals participating in a pre-test questionnaire and 817 participating in a post-test questionnaire. Overall, 46.9% (536/1144) were first-time testers and 26.2% (300/1144) had tested within the last year; 94.3% (768/814) reported using the HIVST, and 2.9% (19/651) reported a reactive result which was associated with first-time testers (p = 0.024). HIVST represents an approach that reached first-time testers and those who had not tested recently. Implementation indicators suggest the importance of leveraging existing community structures and programs for distribution.
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- 2019
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10. Shedding light on a HIV blind spot: Factors associated with men's HIV testing in five African countries.
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Fleming PJ, Rosen JG, Wong VJ, and Carrasco MA
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- Adolescent, Adult, Africa epidemiology, Demography, Developing Countries, Humans, Male, Mass Screening psychology, Mass Screening statistics & numerical data, Middle Aged, Prevalence, Social Stigma, Surveys and Questionnaires, AIDS Serodiagnosis statistics & numerical data, Attitude to Health, HIV Infections diagnosis, HIV Infections epidemiology, Patient Acceptance of Health Care psychology
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Men's relatively low rates of HIV testing has been termed the 'HIV blind spot' and recently declared by UNAIDS as a top priority. This study uses data from five nationally representative Demographic and Health Surveys in Kenya, Malawi, Mozambique, Zambia, and Zimbabwe to explore factors associated with men's lifetime HIV testing. Between 29.3% and 34.9% of men ages 15-49 in these countries had never tested for HIV and men who held accepting attitudes towards gender-based violence, who lacked HIV knowledge, and who held stigmatising views of HIV were more likely to report never testing for HIV. Findings are interpreted, including a discussion of the possible unintended consequences of current 90-90-90 targets on men's relatively low testing rates. The results point to possible intervention opportunities to increase HIV testing among men in high-HIV prevalence settings in Eastern and Southern Africa and emphasise the importance of changing men's perceptions related to stigma and gender norms.
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- 2019
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11. The power of partners: positively engaging networks of people with HIV in testing, treatment and prevention.
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Katz DA, Wong VJ, Medley AM, Johnson CC, Cherutich PK, Green KE, Huong P, and Baggaley RC
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- 2019
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12. Adolescents, young people, and the 90-90-90 goals: a call to improve HIV testing and linkage to treatment.
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Wong VJ, Murray KR, Phelps BR, Vermund SH, and McCarraher DR
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- Adolescent, Female, Global Health, Health Policy, Humans, Male, World Health Organization, Young Adult, Continuity of Patient Care organization & administration, HIV Infections diagnosis, HIV Infections drug therapy
- Abstract
: The current low rates of HIV diagnosis and treatment initiation among adolescents and young people ages 15-24 continues to present a significant challenge to the epidemic control of HIV. With a 'business as usual' approach to HIV testing and linkage to treatment, new infections among adolescents and youth will likely increase, with the burden compounded by the increasing number of youth in Africa, expected to reach 293 million by 2025. Recent studies reveal significant gaps in the HIV clinical cascade among young people as the global community pursues the Joint United Nations Programme on HIV and AIDS 90-90-90 targets. This AIDS supplement was commissioned with the goal of informing program planners, researchers, policymakers, and funding agencies about the development and design of effective adolescent and youth programs, policies, and strategies for improving the first two 90s among adolescents and youth: HIV testing and diagnosis and linkage to care and treatment. Emerging evidence should inform efforts to better target the youth and adolescents who are most at risk, aiming for early diagnosis and treatment initiation for those who are HIV positive, while also ensuring appropriate primary prevention so that those identified as HIV negative remain so.
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- 2017
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13. Towards universal voluntary HIV testing and counselling: a systematic review and meta-analysis of community-based approaches.
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Suthar AB, Ford N, Bachanas PJ, Wong VJ, Rajan JS, Saltzman AK, Ajose O, Fakoya AO, Granich RM, Negussie EK, and Baggaley RC
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- Female, Humans, Male, HIV Infections diagnosis, Mass Screening methods
- Abstract
Background: Effective national and global HIV responses require a significant expansion of HIV testing and counselling (HTC) to expand access to prevention and care. Facility-based HTC, while essential, is unlikely to meet national and global targets on its own. This article systematically reviews the evidence for community-based HTC., Methods and Findings: PubMed was searched on 4 March 2013, clinical trial registries were searched on 3 September 2012, and Embase and the World Health Organization Global Index Medicus were searched on 10 April 2012 for studies including community-based HTC (i.e., HTC outside of health facilities). Randomised controlled trials, and observational studies were eligible if they included a community-based testing approach and reported one or more of the following outcomes: uptake, proportion receiving their first HIV test, CD4 value at diagnosis, linkage to care, HIV positivity rate, HTC coverage, HIV incidence, or cost per person tested (outcomes are defined fully in the text). The following community-based HTC approaches were reviewed: (1) door-to-door testing (systematically offering HTC to homes in a catchment area), (2) mobile testing for the general population (offering HTC via a mobile HTC service), (3) index testing (offering HTC to household members of people with HIV and persons who may have been exposed to HIV), (4) mobile testing for men who have sex with men, (5) mobile testing for people who inject drugs, (6) mobile testing for female sex workers, (7) mobile testing for adolescents, (8) self-testing, (9) workplace HTC, (10) church-based HTC, and (11) school-based HTC. The Newcastle-Ottawa Quality Assessment Scale and the Cochrane Collaboration's "risk of bias" tool were used to assess the risk of bias in studies with a comparator arm included in pooled estimates. 117 studies, including 864,651 participants completing HTC, met the inclusion criteria. The percentage of people offered community-based HTC who accepted HTC was as follows: index testing, 88% of 12,052 participants; self-testing, 87% of 1,839 participants; mobile testing, 87% of 79,475 participants; door-to-door testing, 80% of 555,267 participants; workplace testing, 67% of 62,406 participants; and school-based testing, 62% of 2,593 participants. Mobile HTC uptake among key populations (men who have sex with men, people who inject drugs, female sex workers, and adolescents) ranged from 9% to 100% (among 41,110 participants across studies), with heterogeneity related to how testing was offered. Community-based approaches increased HTC uptake (relative risk [RR] 10.65, 95% confidence interval [CI] 6.27-18.08), the proportion of first-time testers (RR 1.23, 95% CI 1.06-1.42), and the proportion of participants with CD4 counts above 350 cells/µl (RR 1.42, 95% CI 1.16-1.74), and obtained a lower positivity rate (RR 0.59, 95% CI 0.37-0.96), relative to facility-based approaches. 80% (95% CI 75%-85%) of 5,832 community-based HTC participants obtained a CD4 measurement following HIV diagnosis, and 73% (95% CI 61%-85%) of 527 community-based HTC participants initiated antiretroviral therapy following a CD4 measurement indicating eligibility. The data on linking participants without HIV to prevention services were limited. In low- and middle-income countries, the cost per person tested ranged from US$2-US$126. At the population level, community-based HTC increased HTC coverage (RR 7.07, 95% CI 3.52-14.22) and reduced HIV incidence (RR 0.86, 95% CI 0.73-1.02), although the incidence reduction lacked statistical significance. No studies reported any harm arising as a result of having been tested., Conclusions: Community-based HTC achieved high rates of HTC uptake, reached people with high CD4 counts, and linked people to care. It also obtained a lower HIV positivity rate relative to facility-based approaches. Further research is needed to further improve acceptability of community-based HTC for key populations. HIV programmes should offer community-based HTC linked to prevention and care, in addition to facility-based HTC, to support increased access to HIV prevention, care, and treatment., Review Registration: International Prospective Register of Systematic Reviews CRD42012002554 Please see later in the article for the Editors' Summary.
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- 2013
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14. Universal voluntary HIV testing in antenatal care settings: a review of the contribution of provider-initiated testing & counselling.
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Hensen B, Baggaley R, Wong VJ, Grabbe KL, Shaffer N, Lo YR, and Hargreaves J
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- Access to Information, Anti-HIV Agents therapeutic use, Female, HIV, HIV Infections prevention & control, HIV Infections transmission, Humans, Pregnancy, Prenatal Care, Voluntary Programs, AIDS Serodiagnosis, Counseling, HIV Infections diagnosis, Infectious Disease Transmission, Vertical prevention & control, Mass Screening, Patient Acceptance of Health Care, Pregnancy Complications, Infectious diagnosis
- Abstract
Objective: To assess the contribution of provider-initiated testing and counselling (PITC) to achieving universal testing of pregnant women and, from available data on components of PITC, assess whether PITC adoption adheres to pre-test information, post-test counselling procedures and linkage to treatment., Methods: Systematic review of published literature. Findings were collated and data extracted on HIV testing uptake before and after the adoption of a PITC model. Data on pre- and post-test counselling uptake and linkage to anti-retrovirals, where available, were also extracted., Results: Ten eligible studies were identified. Pre-intervention testing uptake ranged from 5.5% to 78.7%. Following PITC introduction, testing uptake increased by a range of 9.9% to 65.6%, with testing uptake ≥85% in eight studies. Where reported, pre-test information was provided to between 91.5% and 100% and post-test counselling to between 82% and 99.8% of pregnant women. Linkage to ARVs for prevention of mother to child transmission (PMTCT) was reported in five studies and ranged from 53.7% to 77.2%. Where reported, PITC was considered acceptable by ANC attendees., Conclusion: Our review provides evidence that the adoption of PITC within ANC can facilitate progress towards universal voluntary testing of pregnant women. This is necessary to increase the coverage of PMTCT services and facilitate access to treatment and prevention interventions. We found some evidence that PITC adoption does not undermine processes inherent to good conduct of testing, with high levels of pre-test information and post-test counselling, and two studies suggesting that PITC is acceptable to ANC attendees., (© 2011 Blackwell Publishing Ltd.)
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- 2012
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15. Elevation of susceptibility to ozone-induced acute tracheobronchial injury in transgenic mice deficient in Clara cell secretory protein.
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Plopper CG, Mango GW, Hatch GE, Wong VJ, Toskala E, Reynolds SD, Tarkington BK, and Stripp BR
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- Animals, Bronchi pathology, Mice, Mice, Knockout, Mice, Transgenic, Respiratory Mucosa drug effects, Respiratory Mucosa pathology, Trachea pathology, Bronchi drug effects, Ozone toxicity, Trachea drug effects, Uteroglobin genetics
- Abstract
Increases in Clara cell abundance or cellular expression of Clara cell secretory protein (CCSP) may cause increased tolerance of the lung to acute oxidant injury by repeated exposure to ozone (O3). This study defines how disruption of the gene for CCSP synthesis affects the susceptibility of tracheobronchial epithelium to acute oxidant injury. Mice homozygous for a null allele of the CCSP gene (CCSP-/-) and wild type (CCSP+/+) littermates were exposed to ozone (0.2 ppm, 8 h; 1 ppm, 8 h) or filtered air. Injury was evaluated by light and scanning electron microscopy, and the abundance of necrotic, ciliated, and nonciliated cells was estimated by morphometry. Proximal and midlevel intrapulmonary airways and terminal bronchioles were evaluated. There was no difference in airway epithelial composition between CCSP+/+ and CCSP-/- mice exposed to filtered air, and exposure to 0.2 ppm ozone caused little injury to the epithelium of both CCSP+/+ and CCSP-/- mice. After exposure to 1.0 ppm ozone, CCSP-/- mice suffered from a greater degree of epithelial injury throughout the airways compared to CCSP+/+ mice. CCSP-/- mice had both ciliated and nonciliated cell injury. Furthermore, lack of CCSP was associated with a shift in airway injury to include proximal airway generations. Therefore, we conclude that CCSP modulates the susceptibility of the epithelium to oxidant-induced injury. Whether this is due to the presence of CCSP on the acellular lining layer surface and/or its intracellular distribution in the secretory cell population needs to be defined.
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- 2006
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16. Temporal and spatial distribution of ciliogenesis in the tracheobronchial airways of mice.
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Toskala E, Smiley-Jewell SM, Wong VJ, King D, and Plopper CG
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- Aging physiology, Animals, Animals, Newborn, Bronchi ultrastructure, Cilia ultrastructure, Female, Gestational Age, Male, Mice, Microscopy, Confocal, Microscopy, Electron, Scanning, Plant Lectins, Time Factors, Trachea ultrastructure, Bronchi embryology, Bronchi growth & development, Cilia physiology, Trachea embryology, Trachea growth & development
- Abstract
Little is known about ciliogenesis as it proceeds through the entire airway tree, from the trachea to the terminal bronchioles, especially during the postnatal period. The purpose of this study was to define the spatial and temporal (prenatal and postnatal) pattern of normal cilia development in the mouse. Three airway generations representing the entire airway tree were examined: trachea, lobar bronchi, and terminal bronchiole. Ciliated cells in lung lobe whole mounts were labeled with a fluorescent dye for confocal microscopy, and ciliated cell surface density was measured for each airway generation and age. The same samples were examined by scanning electron microscopy to verify the appearance of ciliated cells among the differentiating epithelium of the airways. Ciliated cells were first detected in the trachea and lobar bronchi at 16 days gestational age (DGA) and in the terminal bronchioles at 18 DGA. Ciliated cell surface density increased with prenatal and postnatal age at all airway levels. However, the ciliated cell surface density of the trachea and lobar bronchi was always greater compared with the terminal bronchiole. In conclusion, the study revealed that in developing tracheobronchial airways of the mouse: 1) Ciliogenesis differs temporally and spatially by airway generation; 2) Ciliated cell surface density increases with age in all airway generations, but density decreases in a proximal to distal direction; and 3) A significant portion of ciliogenesis continues after birth. This study provides a healthy basis for investigations of neonatal pulmonary disease or pollutant toxicity affecting cilia and its functions.
- Published
- 2005
- Full Text
- View/download PDF
17. Repeated episodes of ozone inhalation amplifies the effects of allergen sensitization and inhalation on airway immune and structural development in Rhesus monkeys.
- Author
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Schelegle ES, Miller LA, Gershwin LJ, Fanucchi MV, Van Winkle LS, Gerriets JE, Walby WF, Mitchell V, Tarkington BK, Wong VJ, Baker GL, Pantle LM, Joad JP, Pinkerton KE, Wu R, Evans MJ, Hyde DM, and Plopper CG
- Subjects
- Administration, Inhalation, Aerosols, Animals, Basement Membrane immunology, Bronchoalveolar Lavage Fluid cytology, Cell Count, Drug Synergism, Eosinophils immunology, Histamine blood, Hypersensitivity, Immediate chemically induced, Hypersensitivity, Immediate pathology, Immunoglobulin E immunology, Macaca mulatta, Mites immunology, Oxidants, Photochemical administration & dosage, Ozone administration & dosage, Respiratory Hypersensitivity chemically induced, Respiratory Hypersensitivity immunology, Respiratory Mechanics drug effects, Skin Tests, Spectrometry, Fluorescence, Allergens toxicity, Oxidants, Photochemical toxicity, Ozone toxicity, Respiratory Hypersensitivity pathology
- Abstract
Twenty-four infant rhesus monkeys (30 days old) were exposed to 11 episodes of filtered air (FA), house dust mite allergen aerosol (HDMA), ozone (O3), or HDMA + O3 (5 days each followed by 9 days of FA). Ozone was delivered for 8 h/day at 0.5 ppm. Twelve of the monkeys were sensitized to house dust mite allergen (Dermatophagoides farinae) at ages 14 and 28 days by subcutaneous inoculation (SQ) of HDMA in alum and intraperitoneal injection of heat-killed Bordetella pertussis cells. Sensitized monkeys were exposed to HDMA aerosol for 2 h/day on days 3-5 of either FA (n = 6) or O3 (n = 6) exposure. Nonsensitized monkeys were exposed to either FA (n = 6) or O3 (n = 6). During the exposure regimen, parameters of allergy (i.e., serum IgE, histamine, and eosinophilia), airways resistance, reactivity, and structural remodeling were evaluated. Eleven repeated 5-day cycles of inhaling 0.5 ppm ozone over a 6-month period had only mild effects on the airways of nonsensitized infant rhesus monkeys. Similarly, the repeated inhalation of HDMA by HDMA-sensitized infant monkeys resulted in only mild airway effects, with the exception of a marked increase in proximal airway and terminal bronchiole content of eosinophils. In contrast, the combined cyclic inhalation of ozone and HDMA by HDMA sensitized infants monkeys resulted in a marked increase in serum IgE, serum histamine, and airways eosinophilia. Furthermore, combined cyclic inhalation of ozone and HDMA resulted in even greater alterations in airway structure and content that were associated with a significant elevation in baseline airways resistance and reactivity. These results suggest that ozone can amplify the allergic and structural remodeling effects of HDMA sensitization and inhalation.
- Published
- 2003
- Full Text
- View/download PDF
18. Detection of viral infection in the respiratory tract of virus antibody free mice: advantages of high-resolution imaging for respiratory toxicology.
- Author
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Phimister AJ, Day KC, Gunderson AD, Wong VJ, Lawson GW, Fanucchi MV, Van Winkle LS, Kendall LV, and Plopper CG
- Subjects
- Animals, Benzoxazoles, Bronchi ultrastructure, Bronchi virology, Cell Membrane metabolism, Cell Membrane ultrastructure, Cell Membrane virology, Cell Membrane Permeability, Ethidium analogs & derivatives, Ethidium metabolism, Fluorescent Dyes, Male, Mice, Microscopy, Confocal, Microscopy, Electron, Microscopy, Fluorescence, Quinolinium Compounds, Respiratory Mucosa metabolism, Respiratory Mucosa ultrastructure, Respiratory Tract Infections diagnosis, Respiratory Tract Infections virology, Retroviridae physiology, Retroviridae ultrastructure, Retroviridae Infections diagnosis, Retroviridae Infections immunology, Respiratory Mucosa virology, Respiratory Tract Infections veterinary, Retroviridae Infections veterinary, Toxicity Tests methods
- Abstract
Using a highly sensitive membrane permeability assay, a viral infection was discovered in the lungs of virus antibody free (VAF) Swiss-Webster mice purchased for respiratory toxicology studies. The assay is based on the uptake of a charged fluorescent compound by cells lacking an intact plasma membrane. Lungs from 74% of the untreated animals from a single vendor tested positive for injury in this assay. High-resolution histopathologic analysis of 1-microm epoxy resin sections from affected animals identified increased peribronchiolar lymphocytic infiltration and markers of epithelial cell injury. Viral particles were directly observed to be budding from the membranes of infiltrating lymphocytic cells by transmission electron microscopy. Standard histological analysis of paraffin-embedded tissues from lungs of the same mice failed to detect obvious pathology. Serological analyses failed to detect the presence of a virus in the affected mice. Therefore, we conclude that (1) a pathogenic condition was present in the respiratory systems of mice judged pathogen free by standard methodologies, (2) the observed condition produced a pattern of injury comparable to those caused by pulmonary toxicants, (3) high-resolution histopathology and advanced imaging techniques can increase the potential for detection of pathological conditions, and (4) apparently healthy animals can have unrecognized infections with the potential for confounding respiratory toxicology studies.
- Published
- 2003
- Full Text
- View/download PDF
19. Colonic spirochetosis of colony-raised rhesus macaques associated with Brachyspira and Helicobacter.
- Author
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Duhamel GE, Stryker CJ, Lu G, Wong VJ, and Tarara RP
- Abstract
Colonic spirochetosis is an inflammatory bowel disease that affects a broad range of hosts, including human and non-human primates. The disease in humans and non-human primates is characterized by intimate attachment of the anaerobic spirochetes Brachyspira aalborgi and B. pilosicoli, and some unclassified flagellated microbes along the apical membrane of colonic enterocytes. Although the presence of spiral-shaped bacteria with single polar flagella and blunted ends in colonic spirochetosis is well established, the identities of many of these organisms is still unknown. Recently, Helicobacter species with a morphology similar to the flagellated bacteria present in colonic spirochetosis have been cultured from intestinal specimens obtained from rhesus macaques, some with idiopathic colitis. The purpose of the present study was to determine whether or not the flagellated bacteria seen in the colons of rhesus macaques with colonic spirochetosis are Helicobacter. The presence of flagellated bacteria alone (n=2) or together with spirochetes (n=1) in formalin-fixed and paraffin-embedded colons of three rhesus macaques with the naturally occurring disease was demonstrated by immunohistochemical staining and ultrastructural examination. Total DNA extracted from affected and control intestinal specimens was amplified by polymerase chain reaction (PCR) using Helicobacter 16S rRNA gene-specific primers. Comparative nucleotide sequence analysis of PCR products cloned from positive reactions indicated that two distinct Helicobacter genomospecies were present either alone or in combination with Brachyspira in the colons of rhesus macaques with microscopic lesions indicative of colonic spirochetosis.
- Published
- 2003
- Full Text
- View/download PDF
20. Repeated episodes of ozone inhalation attenuates airway injury/repair and release of substance P, but not adaptation.
- Author
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Schelegle ES, Walby WF, Alfaro MF, Wong VJ, Putney L, Stovall MY, Sterner-Kock A, Hyde DM, and Plopper CG
- Subjects
- Administration, Inhalation, Animals, Bronchi drug effects, Bronchi metabolism, Bronchi pathology, Bronchoalveolar Lavage, Cell Division drug effects, Epithelial Cells drug effects, Epithelial Cells metabolism, Epithelial Cells pathology, Epithelium drug effects, Epithelium metabolism, Epithelium pathology, Logistic Models, Lung metabolism, Lung pathology, Male, Oxidants, Photochemical administration & dosage, Rats, Respiration drug effects, Time Factors, Trachea metabolism, Adaptation, Physiological drug effects, Lung drug effects, Oxidants, Photochemical toxicity, Ozone administration & dosage, Ozone toxicity, Substance P metabolism, Trachea drug effects
- Abstract
To determine the impact of repeated episodes of ozone exposure on physiologic adaptation, epithelial injury/repair, and tracheal substance P levels, adult rats were subjected to episodes of ozone (5 days, 1 ppm, 8 h/day) followed by 9 days of filtered air for four cycles. Rats were sampled on days 1 and 5 of each episode and 9 days after day 5 of episodes 1, 2, and 4. One hour before being euthanized each rat was injected with 5-bromo-2'-deoxyuridine to label proliferating cells. Each 5-day episode showed a characteristic pattern of rapid shallow breathing (days 1 and 2), epithelial injury, and interstitial and intraluminal inflammation. In contrast, the neutrophil component of inflammation, tracheal substance P release, and cell proliferation became attenuated with each consecutive episode of exposure. Concurrent with this cyclic and attenuated response there was progressive hypercellularity and hyperplasia in all airways studied and a progressive remodeling present in the terminal bronchioles. Our findings are consistent with the notion that the cumulative distal airway lesion is at least in part the result of a depressed cell proliferative response to injury in these airways. This depressed cell proliferative response may be in part the result of diminished neutrophil inflammation and/or release of mitogenic neuropeptides in response to ozone-induced injury.
- Published
- 2003
- Full Text
- View/download PDF
21. Allergic asthma induced in rhesus monkeys by house dust mite (Dermatophagoides farinae).
- Author
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Schelegle ES, Gershwin LJ, Miller LA, Fanucchi MV, Van Winkle LS, Gerriets JP, Walby WF, Omlor AM, Buckpitt AR, Tarkington BK, Wong VJ, Joad JP, Pinkerton KB, Wu R, Evans MJ, Hyde DM, and Plopper CG
- Subjects
- Animals, Antigens, Dermatophagoides, Asthma pathology, Bronchi drug effects, Bronchi immunology, Bronchi metabolism, Bronchial Provocation Tests, Bronchoalveolar Lavage Fluid chemistry, Exudates and Transudates metabolism, Female, Glycoproteins administration & dosage, Histamine administration & dosage, Histamine blood, Histamine immunology, Immunoglobulin E blood, Immunophenotyping, Injections, Subcutaneous, Intradermal Tests, Lymphocytes cytology, Lymphocytes immunology, Macaca mulatta, Mites, Asthma immunology, Glycoproteins immunology
- Abstract
To establish whether allergic asthma could be induced experimentally in a nonhuman primate using a common human allergen, three female rhesus monkeys (Macaca mulatta) were sensitized with house dust mite (Dermatophagoides farinae) allergen (HDMA) by subcutaneous injection, followed by four intranasal sensitizations, and exposure to allergen aerosol 3 hours per day, 3 days per week for up to 13 weeks. Before aerosol challenge, all three monkeys skin-tested positive for HDMA. During aerosol challenge with HDMA, sensitized monkeys exhibited cough and rapid shallow breathing and increased airway resistance, which was reversed by albuterol aerosol treatment. Compared to nonsensitized monkeys, there was a fourfold reduction in the dose of histamine aerosol necessary to produce a 150% increase in airway resistance in sensitized monkeys. After aerosol challenge, serum levels of histamine were elevated in sensitized monkeys. Sensitized monkeys exhibited increased levels of HDMA-specific IgE in serum, numbers of eosinophils and exfoliated cells within lavage, and elevated CD25 expression on circulating CD4(+) lymphocytes. Intrapulmonary bronchi of sensitized monkeys had focal mucus cell hyperplasia, interstitial infiltrates of eosinophils, and thickening of the basement membrane zone. We conclude that a model of allergic asthma can be induced in rhesus monkeys using a protocol consisting of subcutaneous injection, intranasal instillation, and aerosol challenge with HDMA.
- Published
- 2001
- Full Text
- View/download PDF
22. Three-dimensional mapping of ozone-induced acute cytotoxicity in tracheobronchial airways of isolated perfused rat lung.
- Author
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Postlethwait EM, Joad JP, Hyde DM, Schelegle ES, Bric JM, Weir AJ, Putney LF, Wong VJ, Velsor LW, and Plopper CG
- Subjects
- Animals, Bronchoalveolar Lavage Fluid, In Vitro Techniques, L-Lactate Dehydrogenase metabolism, Male, Rats, Rats, Sprague-Dawley, Bronchi drug effects, Lung drug effects, Ozone toxicity, Trachea drug effects
- Abstract
Acute lung injury induced by reactive oxygen gases such as ozone (O(3)) is focal and site-selective. To define patterns of acute epithelial injury along intrapulmonary airways, we developed a new analytic approach incorporating labeling of permeable cells, airway microdissection, and laser scanning confocal microscopy, and applied it to isolated perfused rat lungs where ventilation and breathing pattern could be controlled. After exposure to O(3) (0, 0.25, 0.5, or 1.0 ppm), lungs were lavaged to assess lactate dehydrogenase (LDH) and protein, or infused with the permeability marker ethidium homodimer-1 (EthD-1) via tracheal cannula, gently lavaged, and fixed by airway infusion. The airway tree of the right middle lobe was exposed by microdissection of the axial pathway down to the terminal bronchioles; the dissection was incubated with a second nuclear dye, YOPRO-1, to label all nuclei; and whole mounts were examined by confocal microscopy. Abundance of EthD-1-positive (injured) cells was estimated as the number per epithelial volume using stereology on Z-series of projected images. For ozone concentrations of 1.0 ppm, lavage fluid LDH and total protein did not increase over controls. Exposure produced a concentration- dependent but nonhomogeneous increase in the abundance of EthD-1-labeled cells in proximal and distal conducting airways both in the main pathway, including terminal bronchioles, and in side branches. Overall, the highest EthD-1 labeling occurred in the side branches of the most proximal part of the airway tree at 1 ppm with the adjacent axial pathway airway having approximately one-third the labeling density. Density of EthD-1-labeled cells was lowest in terminal bronchioles at all O(3) doses. For the model we used, identification of injured epithelial cells by differential permeability and laser confocal microscopy appeared to be highly sensitive and permitted mapping of acute cytotoxicity throughout the airway tree and quantitative comparisons of sites with different branching histories and potential dosimetry rates.
- Published
- 2000
- Full Text
- View/download PDF
23. Preimplantation embryo morphology following early luteal phase anti-nidatory treatment with mifepristone (RU486) in the rhesus monkey.
- Author
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Ghosh D, Lalitkumar PG, Wong VJ, Hendrickx AG, and Sengupta J
- Subjects
- Animals, Blastocyst ultrastructure, Embryo, Mammalian drug effects, Embryonic and Fetal Development, Female, Macaca mulatta, Male, Morula ultrastructure, Ovulation, Pregnancy, Progestins antagonists & inhibitors, Time Factors, Trophoblasts ultrastructure, Embryo Implantation drug effects, Embryo, Mammalian ultrastructure, Embryonic Development, Hormone Antagonists pharmacology, Luteal Phase, Mifepristone pharmacology
- Abstract
The ultrastructural characteristics of peri-implantation stage embryos recovered on day 6 after ovulation from rhesus monkeys with or without mifepristone (RU486) treatment during the early luteal phase were examined in the present study. Monkeys were randomly allocated to two groups; group 1 animals were injected s.c. with 2 ml vehicle (1:4, benzyl benzoate: olive oil, v/v, n = 21) and group 2 animals received a single dose of mifepristone (2 mg/kg body weight, w/v, n = 30) in the same volume of vehicle on day 2 after ovulation in mated cycles. On day 6 after ovulation, female monkeys of both groups were laparotomized and their reproductive tracts were flushed to retrieve preimplantation stage embryos. Embryos that showed frank degeneration or desynchrony on gross microscopical examination were not included in the present study. Preimplantation embryo growth on day 6 after ovulation was significantly (P < 0.05) affected in the morula-blastocyst transition stage in mifepristone-treated monkeys compared with that in the control group of monkeys. Ultrastructurally, administration of mifepristone on day 2 after ovulation depressed preimplantation stage embryo development, characterized by loss of cell polarity, lack of mitochondrial maturity, and lack of differentiation in trophoblast cells. Furthermore, preimplantation embryos from mifepristone-treated animals displayed a higher occurrence of inter-blastomere space, intra-cytoplasmic vacuoles, myelinoid bodies, accumulation of lipid droplets, lysosomes, lipofuscins, autophagosomes and multivesicular bodies. Collectively, it appears that the developmental potential of preimplantation embryos was significantly compromised in mifepristone-treated cycles.
- Published
- 2000
- Full Text
- View/download PDF
24. Hair shaft defects visualized after detergent extraction.
- Author
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Rice RH, Wong VJ, Williams ML, Price VH, Hohl D, Sundberg JP, and Pinkerton KE
- Subjects
- Animals, Detergents, Genes, Recessive, Humans, Ichthyosis genetics, Ichthyosis pathology, Keratinocytes metabolism, Mice genetics, Mutation physiology, Transglutaminases genetics, Hair ultrastructure
- Published
- 1999
25. Cross-linked features of mouse pelage hair resistant to detergent extraction.
- Author
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Rice RH, Wong VJ, Pinkerton KE, and Sundberg JP
- Subjects
- Animals, Detergents, Dithiothreitol, Drug Resistance, Hair chemistry, Hair ultrastructure, Hot Temperature, Mice, Mice, Inbred C57BL, Mice, Mutant Strains, Microscopy, Electron, Sodium Dodecyl Sulfate, Hair abnormalities
- Abstract
Cross-linking defects in hair cuticle have been observed in certain rare human disorders (trichothiodystrophy, transglutaminase-deficient lamellar ichthyosis). The hypothesis being investigated is that defective cross-linking in the cuticle or other parts of the fiber is a feature of some mouse mutants in which the hair is sparse or appears structurally unsound. Pelage hair samples from 13 mouse mutants displaying defective hair were extracted with sodium dodecyl sulfate and dithiothreitol at neutral pH and examined by transmission electron microscopy. All samples were indistinguishable after extraction from normal hair fibers in appearance of the medulla and cortex. In the cortex, keratins were completely extractable, but material remaining at the cell boundaries was clearly evident. Cells of the medulla were largely unextracted, containing distinct nuclei and amorphous material in the cytoplasm. In two samples (from mice with the matted/flaky tail and naked mutations) cells of the cuticle, which readily detached from the fiber when incubated at 100 degrees C, were more extensively extracted than normal. Defective cross-linking is thus observable in a minority of mouse hair mutants. The observed perturbation of cross-linking in the cuticle was not accompanied by visible perturbation in the cortex or medulla, indicating that different proteins participate in cross-linking in the different cell types.
- Published
- 1999
- Full Text
- View/download PDF
26. Colonic spirochetal infections in nonhuman primates that were associated with Brachyspira aalborgi, Serpulina pilosicoli, and unclassified flagellated bacteria.
- Author
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Duhamel GE, Elder RO, Muniappa N, Mathiesen MR, Wong VJ, and Tarara RP
- Subjects
- Animals, Bacteria isolation & purification, DNA, Bacterial analysis, Macaca mulatta, Papio, Polymerase Chain Reaction, Spirochaetales Infections microbiology, Brachyspira isolation & purification, Colonic Diseases microbiology, Monkey Diseases microbiology, Spirochaetales Infections veterinary
- Published
- 1997
- Full Text
- View/download PDF
27. Cuticle cell defects in lamellar ichthyosis hair and anomalous hair shaft syndromes visualized after detergent extraction.
- Author
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Rice RH, Wong VJ, Price VH, Hohl D, and Pinkerton KE
- Subjects
- Cross-Linking Reagents, Female, Hair chemistry, Hair drug effects, Humans, Ichthyosis, Lamellar pathology, Male, Reducing Agents pharmacology, Syndrome, Transglutaminases ultrastructure, Detergents pharmacology, Hair pathology, Hair ultrastructure, Hair Diseases pathology, Transglutaminases physiology
- Abstract
Background: The biochemical bases for fragility in most of the rare brittle hair shaft syndromes are unknown. The hypothesis being investigated in several syndromes is that the hair cuticle cells show defects in cross-linked protein features. Since transglutaminases stabilize protein structures by cross-linking them, hair from autosomal recessive lamellar ichthyosis patients lacking keratinocyte transglutaminase was examined to find whether this enzyme participates in hair shaft stabilization., Methods: Hair shaft samples from patients afflicted with lamellar ichthyosis or several brittle hair syndromes were examined ultrastructurally by transmission electron microscopy after vigorous extraction with detergent and reducing agent to reveal cross-linked protein features., Results: In hair cuticle cells from three patients with lamellar ichthyosis the marginal band (A layer) was present but nonuniform and subject to breakage, while in a fourth sample it was missing altogether. The exocuticle appeared less dense than in normal hair, consistent with extensive protein loss during detergent extraction. In cuticle cells from trichothiodystrophy hair, the exocuticle layer was essentially fully extractable in one sample, while in two others (from siblings) the exocuticle appeared less dense and the A layer was absent or greatly reduced in thickness. A sample of proximal trichorrhexis nodosa also displayed defects in cuticle cells, in which the endocuticle layer appeared subject to rupture. The outer cuticle cells in monilethrix hair displayed a thinning of the A layer and less dense exocuticle, while the cortex exhibited regions lacking remnant cell borders. Pili annulati hair displayed large gaps in the cortex, presumably reflecting the air-filled cavities characteristic of this syndrome, and wavy borders of some cuticle cells., Conclusions: Observations with autosomal recessive lamellar ichthyosis hair indicate that keratinocyte transglutaminase has a major role in maturation of the cuticle but appears unnecessary for stabilization of cell borders in the cortex. Defective cross-linking was also evident in cuticle cells of trichothiodystrophy and monilethrix.
- Published
- 1996
- Full Text
- View/download PDF
28. Ultrastructural visualization of cross-linked protein features in epidermal appendages.
- Author
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Rice RH, Wong VJ, and Pinkerton KE
- Subjects
- Amino Acids analysis, Animals, Birds, Cell Membrane ultrastructure, Cross-Linking Reagents, Detergents, Hagfishes, Humans, Keratinocytes ultrastructure, Proteins chemistry, Skin ultrastructure, Transglutaminases metabolism, Dipeptides analysis, Feathers ultrastructure, Hair ultrastructure, Proteins analysis, Tooth ultrastructure
- Abstract
Upon vigorous extraction with ionic detergent under reducing conditions, the macroscopic structures of mammalian hair, bird feather and horny teeth of the hagfish become swollen and flexible but were substantially preserved. In each case, removal in this way of solubilizable constituents, such as disulfide-bonded keratins and associated matrix proteins, left a residue of epsilon-(gamma-glutamyl)lysine cross-linked protein. Residual features in hair included cell envelopes in the cortex, cell envelopes and intracellular deposits in the medulla, and nearly the entire cuticle cells. In feather, extraction left largely intact the macroscopic barb structures but caused collapse of the rachis. In both rachis and barbs, considerable material resembling cell envelopes remained. In extracted hagfish teeth the cellular organization was clearly visible microscopically, including cell borders and remnant nuclei. Unlike the cornified envelopes of mature epidermal keratinocytes, which appear as doublets, reflecting their formation immediately beneath each plasma membrane of apposing cells, the borders of cells of hair cortex and hagfish teeth appeared single and continuous from one cell to the next. Thus the observed cross-linked features comprised four types: (i) condensation immediately beneath the plasma membrane (feather, hair medulla and cuticle) similar to cornified envelopes of epidermal keratinocytes; (ii) deposition between cells (hair cortex, horny teeth); (iii) cytoplasmic deposits (hair cuticle and medulla); and (iv) nuclear condensation (hair medulla, horny teeth). The results emphasize the importance of transglutaminases and their substrate proteins for the function of epidermal appendages and may provide a useful diagnostic test for perturbation of their normal structures.
- Published
- 1994
- Full Text
- View/download PDF
29. Differentiated bronchiolar epithelium in alveolar ducts of rats exposed to ozone for 20 months.
- Author
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Pinkerton KE, Dodge DE, Cederdahl-Demmler J, Wong VJ, Peake J, Haselton CJ, Mellick PW, Singh G, and Plopper CG
- Subjects
- Animals, Bronchi metabolism, Bronchi pathology, Cell Differentiation drug effects, Cilia ultrastructure, Immunohistochemistry, Male, Microscopy, Electron, Scanning, Proteins metabolism, Pulmonary Alveoli metabolism, Pulmonary Alveoli pathology, Rats, Rats, Inbred F344, Time Factors, Bronchi drug effects, Ozone pharmacology, Pulmonary Alveoli drug effects, Uteroglobin
- Abstract
The effects of exposure to 1.0 ppm of ozone for twenty months were studied in male Fischer 344 rats. Light microscopic, morphometric, and immunohistological approaches were used to determine the distribution and degree of differentiation of ciliated and nonciliated bronchiolar epithelial (Clara) cells lining alveolar ducts of the central acinus, a primary target of ozone-induced lung injury. Alveolar duct pathways extending beyond the level of the most proximal alveolar outpocketing of terminal bronchioles were isolated in longitudinal profile. The distance that ciliated and nonciliated bronchiolar epithelial (Clara) cells projected down each alveolar duct pathway was determined by placing concentric arcs radiating outward from a single reference point at the level of the first alveolar outpocketing. A high degree of heterogeneity in the magnitude of bronchiolar epithelial cell extension into alveolar ducts was noted for each isolation and animal. Age-matched control animals also demonstrated variation in the degree of bronchiolar epithelial cell extension down alveolar ducts. In animals exposed to ozone, a striking similarity was noted by scanning electron microscopy in the surface characteristics of cells lining both terminal bronchioles and alveolar ducts. The presence of Clara cell secretory protein in cells of bronchioles and alveolar ducts was also detected immunohistochemically and visualized using confocal laser scanning microscopy in the reflectance mode. Well-differentiated ciliated and nonciliated bronchiolar epithelial cells were found lining alveolar septal tips and alveoli up to a depth of 1,000 mu into the pulmonary acinus after 20 months of exposure to ozone. No evidence of inflammation was present in alveolar ducts, suggesting that epithelial cell transformations in alveolar ducts is a natural consequence of lifetime exposures to oxidant gases.
- Published
- 1993
30. Nonolfactory surface epithelium of the nasal cavity of the bonnet monkey: a morphologic and morphometric study of the transitional and respiratory epithelium.
- Author
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Harkema JR, Plopper CG, Hyde DM, Wilson DW, St George JA, and Wong VJ
- Subjects
- Animals, Cilia ultrastructure, Cytoplasmic Granules ultrastructure, Epithelium ultrastructure, Female, Humans, Male, Microscopy, Electron, Microvilli ultrastructure, Nasopharynx ultrastructure, Species Specificity, Macaca anatomy & histology, Macaca radiata anatomy & histology, Nasal Cavity ultrastructure
- Abstract
The purpose of the present study was to characterize ultrastructurally the nonolfactory nasal epithelium of a nonhuman primate, the bonnet monkey. Nasal cavities from eight subadult bonnet monkeys were processed for light microscopy, and scanning and transmission electron microscopy. Nonolfactory epithelium covered the majority of the nasal cavity and consisted of squamous (SE), transitional (TE), and respiratory epithelium (RE). Stratified SE covered septal and lateral walls of the nasal vestibule, while ciliated pseudostratified RE covered most of the remaining nasal cavity. Stratified, nonciliated TE was present between SE and RE in the anterior nasal cavity. This epithelium was distinct from the other epithelial populations in abundance and types of cells present. TE was composed of lumenal nonciliated cuboidal cells, goblet cells, small mucous granule (SMG) cells, and basal cells, while RE contained ciliated cells, goblet cells, SMG cells, basal cells, and cells with intracytoplasmic lumina lined by cilia and microvilli. TE and RE contained similar numbers of total epithelial cells and basal cells per millimeter of basal lamina. TE was composed of more SMG cells but fewer goblet cells compared to RE. We conclude that nonolfactory nasal epithelium in the bonnet monkey is complex with distinct regional epithelial populations which must be recognized before pathologic changes within this tissue can be assessed adequately.
- Published
- 1987
- Full Text
- View/download PDF
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