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Safety and Immune Responses Following Anti-PD-1 Monoclonal Antibody Infusions in Healthy Persons With Human Immunodeficiency Virus on Antiretroviral Therapy. Open Forum Infect Dis 2024; 11:ofad694. [PMID: 38449916 PMCID: PMC10917183 DOI: 10.1093/ofid/ofad694] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2023] [Accepted: 01/09/2024] [Indexed: 03/08/2024] Open
Abstract
Background T cells in people with human immunodeficiency virus (HIV) demonstrate an exhausted phenotype, and HIV-specific CD4+ T cells expressing programmed cell death 1 (PD-1) are enriched for latent HIV, making antibody to PD-1 a potential strategy to target the latent reservoir. Methods This was a phase 1/2, randomized (4:1), double-blind, placebo-controlled study in adults with suppressed HIV on antiretroviral therapy with CD4+ counts ≥350 cells/μL who received 2 infusions of cemiplimab versus placebo. The primary outcome was safety, defined as any grade 3 or higher adverse event (AE) or any immune-related AE (irAE). Changes in HIV-1-specific polyfunctional CD4+ and CD8+ T-cell responses were evaluated. Results Five men were enrolled (median CD4+ count, 911 cells/μL; median age, 51 years); 2 received 1 dose of cemiplimab, 2 received 2 doses, and 1 received placebo. One participant had a probable irAE (thyroiditis, grade 2); another had a possible irAE (hepatitis, grade 3), both after a single low-dose (0.3 mg/kg) infusion. The Safety Monitoring Committee recommended no further enrollment or infusions. All 4 cemiplimab recipients were followed for 48 weeks. No other cemiplimab-related serious AEs, irAEs, or grade 3 or higher AEs occurred. One 2-dose recipient of cemiplimab had a 6.2-fold increase in polyfunctional, Gag-specific CD8+ T-cell frequency with supportive increases in plasma HIV RNA and decreases in total HIV DNA. Conclusions One of 4 participants exhibited increased HIV-1-specific T-cell responses and transiently increased HIV-1 expression following 2 cemiplimab infusions. The occurrence of irAEs after a single, low dose may limit translating the promising therapeutic results of cemiplimab for cancer to immunotherapeutic and latency reversal strategies for HIV. Clinical Trials Registration. NCT03787095.
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A Trauma-Informed HIV Intervention (LinkPositively) to Improve HIV Care Among Black Women Affected by Interpersonal Violence: Protocol for a Pilot Randomized Controlled Trial. JMIR Res Protoc 2023; 12:e46325. [PMID: 37405824 DOI: 10.2196/46325] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2023] [Revised: 05/31/2023] [Accepted: 05/31/2023] [Indexed: 07/06/2023] Open
Abstract
BACKGROUND Black women bear a disproportionate burden of HIV, accounting for nearly 60% of new diagnoses among US women. Black women living with HIV often experience mutually reinforcing epidemics, known as syndemics, including interpersonal violence and substance use. Syndemics are associated with decreased HIV care engagement and treatment adherence and worsening HIV outcomes. Few HIV services and resources are tailored to be culturally and gender-responsive and trauma informed for Black women living with HIV. Technology-based, psychoeducational, and peer navigation programs offer promising pathways to tailored HIV support and improved HIV care outcomes. Therefore, the web-based, trauma-informed intervention LinkPositively was developed in collaboration with Black women living with HIV to promote uptake of HIV care and ancillary support services. OBJECTIVE This study primarily determines the feasibility and acceptability of the LinkPositively intervention among Black women living with HIV affected by interpersonal violence. The secondary aim is to examine the preliminary impact of the LinkPositively intervention on retention in HIV care, antiretroviral therapy adherence, and viral suppression while evaluating the role of mechanism of change variables (eg, social support) in the associations. METHODS The LinkPositively trial is a pilot randomized controlled trial conducted in California, United States, among 80 adult Black women living with HIV who have experienced interpersonal violence. Core components of LinkPositively include one-on-one peer navigation with phone and SMS text message check-ins; 5 weekly one-on-one video sessions to build coping and care navigation skills; and a mobile app that contains a peer support social networking platform, an educational database with healthy living and self-care tips, a GPS-enabled HIV and ancillary care resource locator, and a medication self-monitoring and reminder system. Participants are randomly assigned to the intervention (n=40) or control (Ryan White standard of care; n=40) arm, with follow-up at 3 and 6 months. At each assessment, participants complete an interviewer-administered survey and submit hair samples for the assessment of HIV medication adherence. All research staff and investigators adhere to ethical principles and guidelines for conducting research activities. Data will be analyzed using generalized estimating equations. RESULTS Final development and testing of the LinkPositively app were completed in July 2021. As of May 2023, we have screened 97 women for eligibility. Of the 97 women screened, 27 (28%) were eligible and have been enrolled in the study. The dissemination of preliminary results will occur in 2024. CONCLUSIONS This trial will advance HIV prevention science by harnessing technology to promote engagement in HIV care while improving social support through peers and social networking-all while being trauma informed for Black women living with HIV with experiences of interpersonal violence. If shown to be feasible and acceptable, LinkPositively has the potential to improve HIV care outcomes among Black women, a marginalized key population. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID) DERR1-10.2196/46325.
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An examination of the association between forced sex history and reproductive coercion experiences among Black women attending STD clinics in Baltimore, MD, USA. Reprod Health 2023; 20:73. [PMID: 37183247 PMCID: PMC10184376 DOI: 10.1186/s12978-023-01602-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2022] [Accepted: 03/27/2023] [Indexed: 05/16/2023] Open
Abstract
BACKGROUND Reproductive coercion victimization (RCV) is a significant public health issue that negatively affects women's sexual and reproductive health outcomes. Less is known about reproductive coercion perpetration (RCP). Few studies have examined these phenomena among representative samples of Black women. METHODS Retrospective data of women (n = 298) attending STD clinics in Baltimore, MD were analyzed. We calculated lifetime and 12-month prevalence reports of reproductive coercion, and reported values stratified by forced sex history. Binomial logistic regression models were used to examine the association between forced sex history and RCV, accounting for other types of violence typologies. RESULTS Lifetime and past 12-month RCV and RCP prevalence were higher among women with forced sex experiences than their counterparts (Lifetime RCV: 46.9% versus 17.5%; past 12-month RCV: 19.4% versus 8.5%. Lifetime RCP: 24.5% versus 17%; past 12-month RCP: 13.3% versus 10.5%). Adjusted models, lifetime reproductive coercion: Women reporting forced sex had a 3.58 times higher odds of having had experienced RCV compared to women not reporting forced sex (AOR 3.58; 95% CI 2.00, 6.46). Women reporting forced sex had a 3.66 times higher odds of having ever experienced pregnancy coercion compared to their counterparts (AOR 3.66; 95% CI 1.93, 7.03) and 4.30 times higher odds of having ever experienced condom manipulation (AOR 4.30; 95% CI 2.15, 8.86). Adjusted models, past 12-month reproductive coercion: Women reporting forced sex had a 2.72 times higher odds of having had experienced past 12-month RCV compared to women not reporting forced sex (AOR 2.72; 95% CI 1.27, 5.91). Women reporting forced sex had a 3.25 times higher odds of having experienced past 12-month pregnancy coercion compared to their counterparts (AOR 3.25; 95% CI 1.38, 7.83) and 3.41 times higher odds of having experienced past 12-month condom manipulation (AOR 3.41; 95% CI 1.14, 10.98). CONCLUSIONS Participants in our study reported high rates of RCV. Our novel exploration revealed significantly high rates of co-occurring forced sex experiences and RCV and initial prevalence report of RCP. Agencies have a unique opportunity to intervene by implementing screening protocols and referrals for supportive services. These findings may inform future intervention research efforts aimed at improving reproductive health outcomes among Black women.
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A Community Call to Action to Prioritize Inclusion and Enrollment of Women in HIV Cure-related Research. J Acquir Immune Defic Syndr 2022; 91:e12-e14. [PMID: 36083494 PMCID: PMC9646409 DOI: 10.1097/qai.0000000000003084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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"It comes altogether as one:" perceptions of analytical treatment interruptions and partner protections among racial, ethnic, sex and gender diverse HIV serodifferent couples in the United States. BMC Public Health 2022; 22:1317. [PMID: 35810288 PMCID: PMC9270765 DOI: 10.1186/s12889-022-13528-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Accepted: 05/25/2022] [Indexed: 02/05/2023] Open
Abstract
BACKGROUND Most HIV cure-related studies involve interrupting antiretroviral treatment to assess the efficacy of pharmacologic interventions - also known as analytical treatment interruptions (ATIs). ATIs imply the risk of passing HIV to sexual partners due to the loss of undetectable HIV status. There has been a notable lack of attention paid to perceptions of ATIs among racial, ethnic, sex and gender minorities, and HIV serodifferent couples. These populations are among those most impacted by HIV in the United States. Future HIV cure research paradigms should equitably include considerations from these groups. METHODS From August - October 2020, we conducted in-depth interviews with 10 racial, ethnic, sex, and gender minority HIV serodifferent couples in geographically diverse regions of the United States to understand their perspectives about ATIs and partner protection measures to prevent secondary HIV transmissions because of participation in ATI studies. We used framework analysis to analyze the qualitative data. RESULTS Of the 10 couples recruited, four identified as a gay couple, two as a gay and bisexual couple, two as a heterosexual couple, one as a gay and queer couple, and one as a queer couple. We found that HIV serodifferent couples in our study viewed ATIs as contradicting HIV treatment adherence messages. Couples expressed discomfort around ATIs in HIV cure research. They were concerned with the return of HIV detectability and worried ATIs might result in secondary HIV transmission. Participants were strongly in favor of using a range of partner protection measures during ATIs that included PrEP, HIV risk reduction counseling, and alternatives for penetrative sex practices. Couples also recommended that sex partners be consulted or involved as part of ATI trials. CONCLUSIONS Our findings highlight new potential opportunities and strategies to mitigate risk of HIV transmission during ATIs among key groups historically under-represented in HIV cure research. Findings also underscore the relational aspects of ATI trials. We provide preliminary considerations for planning ATI trials with diverse HIV serodifferent partners. Future studies should continue to explore these issues among other types of partnerships, cultures, and socio-cultural settings.
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Preliminary Acceptability of a Home-Based Peripheral Blood Collection Device for Viral Load Testing in the Context of Analytical Treatment Interruptions in HIV Cure Trials: Results from a Nationwide Survey in the United States. J Pers Med 2022; 12:231. [PMID: 35207719 PMCID: PMC8879991 DOI: 10.3390/jpm12020231] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 01/13/2022] [Accepted: 01/28/2022] [Indexed: 02/04/2023] Open
Abstract
Frequent viral load testing is necessary during analytical treatment interruptions (ATIs) in HIV cure-directed clinical trials, though such may be burdensome and inconvenient to trial participants. We implemented a national, cross-sectional survey in the United States to examine the acceptability of a novel home-based peripheral blood collection device for HIV viral load testing. Between June and August 2021, we distributed an online survey to people with HIV (PWH) and community members, biomedical HIV cure researchers and HIV care providers. We performed descriptive analyses to summarize the results. We received 73 survey responses, with 51 from community members, 12 from biomedical HIV cure researchers and 10 from HIV care providers. Of those, 51 (70%) were cisgender men and 50 (68%) reported living with HIV. Most (>80% overall) indicated that the device would be helpful during ATI trials and they would feel comfortable using it themselves or recommending it to their patients/participants. Of the 50 PWH, 42 (84%) indicated they would use the device if they were participating in an ATI trial and 27 (54%) also expressed a willingness to use the device outside of HIV cure studies. Increasing sensitivity of viral load tests and pluri-potency of the device (CD4 count, chemistries) would augment acceptability. Survey findings provide evidence that viral load home testing would be an important adjunct to ongoing HIV cure-directed trials involving ATIs. Survey findings may help inform successful implementation and uptake of the device in the context of personalized HIV care.
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Considerations for Increasing Racial, Ethnic, Gender, and Sexual Diversity in HIV Cure-Related Research with Analytical Treatment Interruptions: A Qualitative Inquiry. AIDS Res Hum Retroviruses 2022; 38:50-63. [PMID: 33947268 PMCID: PMC8785755 DOI: 10.1089/aid.2021.0023] [Citation(s) in RCA: 28] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Despite disproportionate incidence and prevalence of HIV among transgender individuals, cisgender women, and racial and ethnic minority groups, all remain underrepresented in HIV cure research. As HIV cure trials are scaled up, there is emerging research on ways to mitigate risks of HIV acquisition for sexual partners of analytical treatment interruption (ATI) trial participants. As such, it is imperative that HIV cure researchers consider the implications of implementing ATIs in populations that are disproportionately affected by HIV, but largely underrepresented in trials to date. In this qualitative study, we sought to derive triangulated perspectives on the social and ethical implications regarding ATIs and partner protection strategies during ATIs among under-represented populations. We conducted 21 in-depth interviews with 5 types of informants: bioethicists, community members [people living with HIV (PLWH) and their advocates], biomedical HIV cure researchers, sociobehavioral scientists, and HIV care providers. We analyzed the data using conventional content analysis and reduced the data to important considerations for implementing ATI trials in diverse communities and settings. Our study revealed the following key themes: (1) attention must be paid to gender and power dynamics in ATI trials; (2) ATI trials should be designed and implemented through the lenses of intersectionality and equity frameworks; (3) ATI trials may have both positive and negative effects on stigma for PLWH and their partners; and (4) partnership dynamics should be considered when designing ATI protocols. Our study generated actionable considerations that could be implemented in ATI trials to promote their acceptability to communities that have been underrepresented in HIV cure research to date. Research teams must invest in robust community and stakeholder engagement to define best practices. Paying attention to representation and equity will also promote better and more equitable implementation of HIV cure strategies once these become ready for rollout.
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Suspected Immune-Related Adverse Events With an Anti-PD-1 Inhibitor in Otherwise Healthy People With HIV. J Acquir Immune Defic Syndr 2021; 87:e234-e236. [PMID: 33929394 PMCID: PMC8263135 DOI: 10.1097/qai.0000000000002716] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
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Abstract
The development of the National Institutes of Health (NIH) COVID-19 Treatment Guidelines began in March 2020 in response to a request from the White House Coronavirus Task Force. Within 4 days of the request, the NIH COVID-19 Treatment Guidelines Panel was established and the first meeting took place (virtually-as did subsequent meetings). The Panel comprises 57 individuals representing 6 governmental agencies, 11 professional societies, and 33 medical centers, plus 2 community members, who have worked together to create and frequently update the guidelines on the basis of evidence from the most recent clinical studies available. The initial version of the guidelines was completed within 2 weeks and posted online on 21 April 2020. Initially, sparse evidence was available to guide COVID-19 treatment recommendations. However, treatment data rapidly accrued based on results from clinical studies that used various study designs and evaluated different therapeutic agents and approaches. Data have continued to evolve at a rapid pace, leading to 24 revisions and updates of the guidelines in the first year. This process has provided important lessons for responding to an unprecedented public health emergency: Providers and stakeholders are eager to access credible, current treatment guidelines; governmental agencies, professional societies, and health care leaders can work together effectively and expeditiously; panelists from various disciplines, including biostatistics, are important for quickly developing well-informed recommendations; well-powered randomized clinical trials continue to provide the most compelling evidence to guide treatment recommendations; treatment recommendations need to be developed in a confidential setting free from external pressures; development of a user-friendly, web-based format for communicating with health care providers requires substantial administrative support; and frequent updates are necessary as clinical evidence rapidly emerges.
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Ethics of HIV cure research: an unfinished agenda. BMC Med Ethics 2021; 22:83. [PMID: 34193141 PMCID: PMC8243312 DOI: 10.1186/s12910-021-00651-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Accepted: 06/23/2021] [Indexed: 02/07/2023] Open
Abstract
Background The pursuit of a cure for HIV is a high priority for researchers, funding agencies, governments and people living with HIV (PLWH). To date, over 250 biomedical studies worldwide are or have been related to discovering a safe, effective, and scalable HIV cure, most of which are early translational research and experimental medicine. As HIV cure research increases, it is critical to identify and address the ethical challenges posed by this research. Methods We conducted a scoping review of the growing HIV cure research ethics literature, focusing on articles published in English peer-reviewed journals from 2013 to 2021. We extracted and summarized key developments in the ethics of HIV cure research. Twelve community advocates actively engaged in HIV cure research provided input on this summary and suggested areas warranting further ethical inquiry and foresight via email exchange and video conferencing. Discussion Despite substantial scholarship related to the ethics of HIV cure research, additional attention should focus on emerging issues in six categories of ethical issues: (1) social value (ongoing and emerging biomedical research and scalability considerations); (2) scientific validity (study design issues, such as the use of analytical treatment interruptions and placebos); (3) fair selection of participants (equity and justice considerations); (4) favorable benefit/risk balance (early phase research, benefit-risk balance, risk perception, psychological risks, and pediatric research); (5) informed consent (attention to language, decision-making, informed consent processes and scientific uncertainty); and (6) respect for enrolled participants and community (perspectives of people living with HIV and affected communities and representation). Conclusion HIV cure research ethics has an unfinished agenda. Scientific research and bioethics should work in tandem to advance ethical HIV cure research. Because the science of HIV cure research will continue to rapidly advance, ethical considerations of the major themes we identified will need to be revisited and refined over time.
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Impact of dedicated women's outreach workers (WOWs) on recruitment of women in ACTG clinical studies. HIV Res Clin Pract 2021; 22:37-45. [PMID: 34143949 DOI: 10.1080/25787489.2021.1938825] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
BACKGROUND Despite efforts by the AIDS Clinical Trials Group (ACTG) to enroll representative numbers of diverse women, participation in ACTG studies in the United States remains largely white and male. To address this gap in women's participation in ACTG research, a one-year pilot study of dedicated women's outreach workers (WOWs) was proposed. OBJECTIVES included demonstrating that targeted recruitment efforts can expand community awareness of ACTG research and ensuring successful enrollment of women at the respective clinical research sites. METHODS The pilot study was conducted at two U.S. sites (Rutgers New Jersey Medical School and Emory Ponce de Leon Center in Atlanta, Georgia). The WOWs worked with site personnel to identify and reach out to women living with HIV and/or Hepatitis B or C at their respective sites and encourage them to join a clinical trial registry for those interested in participating in future clinical trials. RESULTS The Rutgers WOW approached 127 potential participants (of whom 100 joined the WOW registry) and screened 35 participants for open ACTG studies. The Emory WOW approached 120 participants, enrolling 86 into the WOW registry, and screened 51 potential participants for open ACTG studies during the WOW's tenure. The majority of women screened at both sites were women of color. CONCLUSIONS The WOW study team identified several lessons learned that can inform future efforts to engage women living with HIV in clinical research. First, success in engaging women is proportional to level of funding and institutional support. Second, there is a need for a more gender-inclusive scientific agenda as women are more likely to participate if studies address topics of interest to them. Third, meaningful engagement is a two-way street.
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Ethical and practical considerations for mitigating risks to sexual partners during analytical treatment interruptions in HIV cure-related research. HIV Res Clin Pract 2021; 22:14-30. [PMID: 33757411 DOI: 10.1080/25787489.2021.1902116] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
BACKGROUND Background: Analytical treatment interruptions (ATIs) in HIV cure-related research can result in trial participants becoming viremic with HIV, placing HIV-negative sexual partners at elevated risk of acquiring HIV. OBJECTIVE Objective:Our study aimed to generate ethical and practical considerations for designing and implementing appropriate risk mitigation strategies to reduce unintended HIV transmission events during ATIs. METHODS Methods: We conducted 21 in-depth interviews with five types of informants: bioethicists, community members, biomedical HIV cure researchers, socio-behavioral scientists/epidemiologists, and HIV care providers. We used conventional content analysis to analyze the data and generate considerations. RESULTS Results: Key findings include: 1) Ethical permissibility of ATI trials depends on due diligence and informed consent to mitigate risks to participants and their sexual partners; 2) Participants should receive adequate support and/or counseling if they choose to disclose ATI participation to their partners; 3) Measures to protect sexual partners of trial participants from HIV transmission during ATIs should include referral to and/or provision of pre-exposure prophylaxis, as well as other available means of preventing HIV transmission; 4) There is uncertainty regarding the appropriate management of emerging sexually transmitted infections during ATI trials and possible protection measures for multiple and/or anonymous partners of ATI trial participants. CONCLUSION Conclusion: While there is no way to completely eliminate the risk of HIV transmission to sexual partners during ATIs, HIV cure trialists and sponsors should consider the ethical concerns related to the sexual partners of ATI participants. Doing so is essential to ensuring the welfare of participants, their partners and the trustworthiness of research.
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Reasons People Living with HIV Might Prefer Oral Daily Antiretroviral Therapy, Long-Acting Formulations, or Future HIV Remission Options. AIDS Res Hum Retroviruses 2020; 36:1054-1058. [PMID: 32829645 DOI: 10.1089/aid.2020.0107] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
A growing body of research is beginning to elucidate reasons people living with HIV (PLWHIV) might prefer oral daily antiretroviral treatment (ART) compared with emerging long-acting ART (LA-ART) or HIV remission strategies under investigation. Our objective is to provide qualitative insights into the reasons why PLWHIV might prefer one of these HIV control therapies over others. From May to August 2018, we implemented a semistructured cross-sectional survey of PLWHIV in the United States to better understand patient preferences around various HIV treatment and remission options. Using free text, respondents were asked to explain why they preferred one HIV control option over the other two. We analyzed responses to the open-ended survey questions on reasons for preferring oral daily ART versus LA-ART versus HIV remission strategies using conventional content analysis. The results showed that PLWHIV preferred oral daily ART because of its familiarity and known safety and efficacy profile, whereas those who preferred LA-ART would value the convenience it offers. Finally, HIV remission strategies would be preferred to avoid taking ART altogether. The qualitative results provide insights into reasons why PLWHIV in the United States might prefer oral daily ART versus novel therapies. More importantly, they provide information to better align HIV virological control strategies with end-user perspectives. To make informed choices around evolving HIV therapeutics, PLWHIV and HIV care providers would benefit from decision tools to better assess options and trade-offs. More research is needed on how best to effectively support PLWHIV and HIV care providers in shared decision-making.
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Source attributed case-control study of campylobacteriosis in New Zealand. Int J Infect Dis 2020; 103:268-277. [PMID: 33221520 DOI: 10.1016/j.ijid.2020.11.167] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Revised: 11/11/2020] [Accepted: 11/15/2020] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Following an initial reduction in human campylobacteriosis in New Zealand after the implementation of poultry food chain-focused interventions during 2006-2008, further decline has been relatively small. We report a year-long study of notified campylobacteriosis cases, incorporating a case control study combined with a source attribution study. The purpose was to generate up-to-date evidence on the relative contributions of different sources of campylobacteriosis in New Zealand. METHODS The study approach included: • A case-control study of notified cases (aged six months or more) sampled in a major urban centre (Auckland, every second case) and a mixed urban/rural area (Manawatū/Whanganui, every case), between 12 March 2018 and 11 March 2019. • Source attribution of human campylobacteriosis cases sampled from these two regions over the study period by modelling of multilocus sequence typing data of Campylobacter jejuni and C. coli isolates from faecal samples of notified human cases and relevant sources (poultry, cattle, sheep). RESULTS Most cases (84%) were infected with strains attributed to a poultry source, while 14% were attributed to a cattle source. Approximately 90% of urban campylobacteriosis cases were attributed to poultry sources, compared to almost 75% of rural cases. Poultry consumption per se was not identified as a significant risk factor. However specific risk factors related to poultry meat preparation and consumption did result in statistically significantly elevated odds ratios. CONCLUSIONS The overall findings combining source attribution and analysis of specific risk factors indicate that poultry meat remains a dominant pathway for exposure and infection.
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Breastfeeding by Women Living With Human Immunodeficiency Virus in a Resource-Rich Setting: A Case Series of Maternal and Infant Management and Outcomes. J Pediatric Infect Dis Soc 2020; 9:228-231. [PMID: 30753640 DOI: 10.1093/jpids/piz003] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/15/2018] [Accepted: 01/10/2019] [Indexed: 11/14/2022]
Abstract
The reduction in human immunodeficiency virus (HIV) transmission through breastmilk with maternal combination antiretroviral therapy (cART) has led many pregnant women living with HIV and healthcare providers to question exclusive formula feeding in resource-rich settings. Here, we describe cART prophylaxis in 3 breastfed infants whose mothers had sustained virologic suppression; all 3 of these infants remained uninfected.
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Participant Perspectives in an HIV Cure-Related Trial Conducted Exclusively in Women in the United States: Results from AIDS Clinical Trials Group 5366. AIDS Res Hum Retroviruses 2020; 36:268-282. [PMID: 32160755 DOI: 10.1089/aid.2019.0284] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Women remain underrepresented in HIV research. The AIDS Clinical Trials Group (ACTG) 5366 study was the first HIV cure-related trial conducted exclusively in women. Our multidisciplinary team integrated participant-centered reports into the ACTG 5366 protocol to elicit their perspectives. We nested mixed-methods surveys at the enrollment and final study visits to assess ACTG 5366 participants' perceptions and experiences. Of 31 participants enrolled in the ACTG 5366, 29 study agreed to complete the entry questionnaire and 27 completed the exit survey. The majority of study participants were nonwhite. We identified societal and personal motivators for participation, understanding of risks and benefits, and minor misconceptions among some trial participants. Stigma was pervasive for several women who joined the study, and served as a motivator for study participation. Reimbursements to defray costs of study participation were reported to facilitate involvement in the trial by about one-third of participants. Almost all respondents reported positive experiences participating in the ACTG 5366 trial. The ACTG 5366 study showed that it is possible to recruit and retain women in HIV cure-related research and to embed participant-centered outcomes at strategic time points during the study. The findings could help in the design, implementation, recruitment, and retention of women in HIV cure-related research and highlight the value of assessing psychosocial factors in HIV cure-related research participation.
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Improving health systems through innovation in population health and health services research. Public Health Res Pract 2018; 28:2831814. [PMID: 30406255 DOI: 10.17061/phrp2831814] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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Increasing the use of research in population health policies and programs: a rapid review. Public Health Res Pract 2018; 28:2831816. [PMID: 30406257 DOI: 10.17061/phrp2831816] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
BACKGROUND AND OBJECTIVES Although the body of literature on factors that impede and enhance the use of research in policy making continues to expand, there is limited evidence about strategies that are effective at fostering the use of research in population health policy and programs. Building on previous reviews, we reviewed the published literature to identify and assess papers describing intervention studies that had outcome measures relating to research use. STUDY TYPE Rapid review. METHODS We searched four academic databases and Google Scholar to identify papers published between 2009 and 2015. Our focus was on strategies relevant to population health policy and program delivery. For studies that tested strategies to increase the use of research, we extracted details about the intervention, participants, study sites and methods, and primary and other outcomes. RESULTS We identified 14 articles reporting on 13 intervention studies. The studies were relatively weak methodologically and together provide few indications of effect. Only one study used an experimental design and one other used pre-/post-test design; the remaining studies were characterised by an absence of control groups, small sample sizes, and self-report data. Of the 13 studies: four intervention studies were related to the theme 'relevant, useful, accessible research'; five studies (described in six papers) tested strategies that facilitated interaction between researchers and research users; three studies assessed strategies aimed at enhancing the capacity of organisations to use research; and one intervention study was related to the theme 'funding research infrastructure and research projects'. CONCLUSION The level of evidence for the effectiveness of strategies to improve the use of research in policy making is low, and there remains a need for well-designed empirical studies that evaluate interventions. In the absence of strong evidence, efforts to enhance research use should be tailored to organisational needs and may incorporate capability development, improved access to targeted research summaries and syntheses, and greater interaction and collaboration with researchers.
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The Prevention Research Support Program: supporting innovation in research, translation and capability building. Public Health Res Pract 2018; 28:2831819. [PMID: 30406264 DOI: 10.17061/phrp2831819] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
OBJECTIVES The Prevention Research Support Program (PRSP) is a New South Wales (NSW) Ministry of Health funding scheme. The scheme aims to build capability, and strengthen prevention and early intervention research that is important to the NSW public health system (NSW Health) and that leads to improved health and reduced health inequities for the people of NSW. This paper describes how PRSP funding has supported recipients to produce high-quality, policy-relevant research, and increase the impact of research on policy and practice. Type of program: The PRSP is a competitive funding program that supports NSW research organisations that conduct prevention and early intervention research that aligns with NSW Health priorities. The objectives of the PRSP are to: increase high-quality and internationally recognised prevention research in NSW; support the generation of research evidence that addresses NSW Health prevention priorities, including cross-government priorities; encourage the adoption of research evidence in relevant policies, programs and services in NSW; and build the prevention research capability of NSW Health staff and the NSW Health system. METHODS Funding recipients provide information about their research, translation and capability building achievements in their funding applications and submit annual progress reports. Data from these sources were aggregated to illustrate trends in indicators of research excellence over time. Prior to the most recent call for applications, the program was reviewed. The review included consultations with funding recipients, policy and practice partners, and key funding stakeholders. Stakeholders' perceptions of the benefits and challenges associated with the PRSP were drawn from the consultation data. RESULTS PRSP funding recipients demonstrate considerable increases over time on several indicators of research excellence, including peer-reviewed journal publications, grant income, and research students supervised. Recipients use a range of strategies to ensure dialogue with health system partners, and report research impacts at the local, state, national and international levels. PRSP funding also supports the development of research capability. LESSONS LEARNT The PRSP is a unique scheme that is highly valued by both funding recipients and health system stakeholders. The continuity of funding provided under the scheme enables recipients to adopt a strategic approach to their research and develop innovative strategies to support its conduct and use.
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The Inhibition by Plasma of Urokinase and Tissue Activator-Induced Fibrinolysis in Pregnancy and the Puerperium. Thromb Haemost 2018. [DOI: 10.1055/s-0038-1657307] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
SummaryThe activity of urokinase and tissue activator on fibrin plates was inhibited by plasma from women in the third trimester of pregnancy to a greater extent than by non-pregnant plasma. Pregnancy also inhibited the amidolytic activity of urokinase. The high molecular weight fractions of pregnancy plasma gel filtered on Sephadex G-200 showed comparable inhibitory activity against urokinase as fractions for non-pregnant plasma; in contrast with non-pregnant plasma, the lower molecular weight fractions of pregnancy plasma were markedly inhibitory against urokinase. Plasma exposed to lysine-Sepharose to remove plasminogen and then fractionated on Sephadex G-100 provided a pattern of three areas of inhibition against tissue activator similar to that seen in non-pregnant plasma. The urokinase-inhibitory activity of lower molecular weight fractions of plasma separated on Sephadex G-200 fell within 1 hr of delivery and fell further over the following 18 to 30 hr.
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Abstract
SummaryAmniotic fluid inhibited the fibrinolytic, amidolytic and esterolytic activity of urokinase. Kinetic studies with AGLMe demonstrated non-competitive inhibition. A major part of the inhibitory activity could be separated from α1-antitrypsin by ion-exchange chromatography on DEAE-Sephadex A-50. Plasminogen activator prepared from porcine heart was not inhibited by amniotic fluid. Amniotic fluid also inhibited the caseinolytic and amidolytic activities of plasmin.
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25: Surveillance of Severe Neonatal Hyperbilirubinemia in Canada. Paediatr Child Health 2014. [DOI: 10.1093/pch/19.6.e35-25] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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152: Impact of Video-Debriefing Following Simulated Neonatal Resuscitation in Inter-Professional Teams. Paediatr Child Health 2014. [DOI: 10.1093/pch/19.6.e35-149] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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167: Comparing Rate of Severe Neonatal Hyperbilirubinemia in Three Western Industrialized Populations: Canada, the United Kingdom & Ireland, and Switzerland. Paediatr Child Health 2014. [DOI: 10.1093/pch/19.6.e35-163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Abstract
BACKGROUND AND AIM Identification of ischaemic stroke subtype currently relies on clinical evaluation supported by various diagnostic studies. The authors sought to determine whether specific diffusion-weighted MRI (DWI) patterns could reliably guide the subsequent work-up for patients presenting with acute ischaemic stroke symptoms. METHODS 273 consecutive patients with acute ischaemic stroke symptoms were enrolled in this prospective, observational, single-centre NIH-sponsored study. Electrocardiogram, non-contrast head CT, brain MRI, head and neck magnetic resonance angiography (MRA) and transoesophageal echocardiography were performed in this prespecified order. Stroke neurologists determined TOAST (Trial of Org 10172 in Acute Stroke Treatment) classification on admission and on discharge. Initial TOAST stroke subtypes were compared with the final TOAST subtype. If the final subtype differed from the initial assessment, the diagnostic test deemed the principal determinant of change was recorded. These principal determinants of change were compared between a CT-based and an MRI-based classification schema. RESULTS Among patients with a thromboembolic DWI pattern, transoesophageal echocardiography was the principal determinant of diagnostic change in 8.8% versus 0% for the small vessel group and 1.7% for the other group (p<0.01). Among patients with the combination of a thromboembolic pattern on MRI and a negative cervical MRA, transoesophageal echocardiography led to a change in diagnosis in 12.1%. There was no significant difference between groups using a CT-based scheme. CONCLUSIONS DWI patterns appear to predict stroke aetiologies better than conventional methods. The study data suggest an MRI-based diagnostic algorithm that can potentially obviate the need for echocardiography in one-third of stroke patients and may limit the number of secondary extracranial vascular imaging studies to approximately 10%.
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Investigation of non-linear acoustic losses at the open end of a tube. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2011; 129:1261-1272. [PMID: 21428489 DOI: 10.1121/1.3543987] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
At high acoustic level, non-linear losses at the end of a tube are usually interpreted as the consequence of a jet formation at the tube end resulting in annular vortices dissipating part of the acoustic energy. Previous work has shown that two different regimes may occur. The present work, using particle image velocimetry visualization, lattice Boltzmann method simulation in 2D, and an analytical model, shows that the two different regimes correspond to situations for which the annular vortices remain attached to the tube (low acoustic particle velocity) or detached (high acoustic particle velocity).
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Hereditary angioedema and pregnancy: successful management of recurrent and frequent attacks of angioedema with C1-inhibitor concentrate, danazol and tranexamic acid - a case report. Obstet Med 2009; 2:123-5. [PMID: 27582827 DOI: 10.1258/om.2009.090003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/25/2009] [Indexed: 11/18/2022] Open
Abstract
Hereditary angioedema (HAE) is a rare but potentially life-threatening condition caused by deficiency of C1 esterase inhibitor. It is characterized by subcutaneous swelling in any part of the skin, gastrointestinal and respiratory tracts. We present the case of a pregnant woman with known HAE that deteriorated during pregnancy with frequent attacks that were managed successfully with danazol, tranexamic acid and regular intravenous administration of C1 esterase inhibitor.
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Increasing the use of evidence in health policy: practice and views of policy makers and researchers. AUSTRALIA AND NEW ZEALAND HEALTH POLICY 2009; 6:21. [PMID: 19698186 PMCID: PMC2739528 DOI: 10.1186/1743-8462-6-21] [Citation(s) in RCA: 140] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/02/2008] [Accepted: 08/24/2009] [Indexed: 11/15/2022]
Abstract
Background Better communication is often suggested as fundamental to increasing the use of research evidence in policy, but little is known about how researchers and policy makers work together or about barriers to exchange. This study explored the views and practice of policy makers and researchers regarding the use of evidence in policy, including: (i) current use of research to inform policy; (ii) dissemination of and access to research findings for policy; (iii) communication and exchange between researchers and policy makers; and (iv) incentives for increasing the use of research in policy. Methods Separate but similar interview schedules were developed for policy makers and researchers. Senior policy makers from NSW Health and senior researchers from public health and health service research groups in NSW were invited to participate. Consenting participants were interviewed by an independent research company. Results Thirty eight policy makers (79% response rate) and 41 researchers (82% response rate) completed interviews. Policy makers reported rarely using research to inform policy agendas or to evaluate the impact of policy; research was used more commonly to inform policy content. Most researchers reported that their research had informed local policy, mainly by increasing awareness of an issue. Policy makers reported difficulty in accessing useful research syntheses, and only a third of researchers reported developing targeted strategies to inform policy makers of their findings. Both policy makers and researchers wanted more exchange and saw this as important for increasing the use of research evidence in policy; however, both groups reported a high level of involvement by policy makers in research. Conclusion Policy makers and researchers recognise the potential of research to contribute to policy and are making significant attempts to integrate research into the policy process. These findings suggest four strategies to assist in increasing the use of research in policy: making research findings more accessible to policy makers; increasing opportunities for interaction between policy makers and researchers; addressing structural barriers such as research receptivity in policy agencies and a lack of incentives for academics to link with policy; and increasing the relevance of research to policy.
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A Cognitive Aid for Neonatal Resuscitation: a Randomized Controlled Trial Using High Fidelity Simulation. Paediatr Child Health 2009. [DOI: 10.1093/pch/14.suppl_a.30a] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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The Incidence of Kernicterus in Canada 2007–2009. Paediatr Child Health 2009. [DOI: 10.1093/pch/14.suppl_a.36ab] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Iron Status in Low Birth Weight Preterm and Near-Term Infants. Paediatr Child Health 2009. [DOI: 10.1093/pch/14.suppl_a.30aa] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Abstract
OBJECTIVE Folic acid supplement use is recommended in pregnancy to reduce the risk of neural tube defect but concerns have been raised that increasing folic acid intake may select for embryos with genotypes that increase disease risk in the offspring. Our aim was to test for this effect. DESIGN Observational prospective cohort study. SETTING Aberdeen Maternity Hospital. POPULATION OR SAMPLE Women born before the introduction of folic acid advice (1970-80) and carrying singleton pregnancies (n = 1234) and their offspring (n = 1083) born after (2001-03). METHODS We measured the genotype (MTHFR C677T and A1298C, MTR A2756G, MTRR A66G and TCN G776C) of mothers and their offspring, maternal supplement intake, intake of folate and vitamin B12 from natural foods and maternal blood folate and B12 status at 19 weeks of gestation. MAIN OUTCOME MEASURES B vitamin related genotype of the offspring. RESULTS There were no significant differences in any of the five genotype frequencies between mothers and their babies. There was no deviation from Hardy-Weinberg equilibrium in either generation and no change in the frequency of doubly homozygous MTHFR variants (677 TT/1298 CC). The genotype of the offspring was not related to maternal periconceptual supplement use, folate intake from foods or plasma and red cell folate measured at 19 weeks of gestation. CONCLUSIONS We found no evidence to support the concern that folic acid fortification or supplement use in pregnancy results in selection of deleterious genotypes.
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Abstract
OBJECTIVE To compare the feasibility of continuous positive airway pressure (CPAP) support generated by high flow nasal cannula with conventional CPAP for prevention of reintubation among preterm infants with a birth weight of <or=1,250 g. STUDY DESIGN Preterm infants were randomized to CPAP generated via high flow cannula or the Infant Flow Nasal CPAP System (VIASYS, Conshohocken, PA, USA) at extubation. Primary outcome was incidence of reintubation within 7 days. Secondary outcomes included change in oxygen use and frequency of apnea and bradycardias postextubation. RESULTS Forty neonates were randomized. Twelve of 20 infants randomized to high flow cannula CPAP were reintubated compared to three of 20 using Infant Flow (P=0.003). The high flow cannula group had increased oxygen use and more apneas and bradycardias postextubation. CONCLUSIONS CPAP delivered by high flow nasal cannula failed to maintain extubation status among preterm infants <or=1,250 g as effectively as Infant Flow CPAP.
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Abstract
BACKGROUND Women who deliver by caesarean section have been shown to be less likely to have a subsequent pregnancy. It is not clear whether this is due to a direct effect of the procedure on future fertility or due to deliberate avoidance of a future pregnancy. OBJECTIVE To investigate whether absence of conception following caesarean section is voluntary or involuntary. DESIGN Follow up of a population-based retrospective cohort. SETTING Grampian region, Scotland. POPULATION Women who had no further viable pregnancies within 5 years of an initial delivery. METHODS Cases included women who delivered their first child by caesarean section between 1980 and 1995 but had no further viable pregnancies by December 2000. Controls included women who delivered their first child during the same period, by means of either spontaneous vaginal delivery (SVD) or instrumental vaginal delivery (IVD), and who had no further viable pregnancies by December 2000. Eligible women were identified from the Aberdeen Maternity and Neonatal Databank (AMND) and sent postal questionnaires to determine the extent to which not conceiving after first delivery was voluntary and the reasons for avoiding further pregnancies. Characteristics of the different mode of delivery groups were compared using univariate techniques. MAIN OUTCOME MEASURES Extent to which absence of conception following an initial delivery by caesarean section is voluntary. RESULTS Questionnaires were returned by 3204 (60%) of 5300 women identified from the AMND. Of these, 1675 women had not conceived at all during the follow-up period (median duration = 13 years). Absence of conception was voluntary in 488 (69%; 95% CI 66-73%) women following caesarean section, 340 (71%; 95% CI 67-76%) following SVD and 354 (72%; 95% CI 68-76%) following IVD. Few women considered seeking fertility treatment (caesarean section = 72 [10%], SVD = 50 [11%], IVD = 39 [8%]). Of the women who decided to delay or avoid a further pregnancy, fewer women who delivered by SVD reported that the birth experience influenced their decision (caesarean section = 163 [32%], SVD = 67 [18%], IVD = 136 [35%]; P < 0.001). CONCLUSIONS Irrespective of mode of delivery, not conceiving following the birth of the first child is mainly voluntary. The experience of the previous birth is one of several factors affecting women's decisions to avoid a subsequent pregnancy.
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Numerical simulation of particle motion in an ultrasound field using the lattice Boltzmann model. ULTRASONICS 2004; 43:21-25. [PMID: 15358525 DOI: 10.1016/j.ultras.2004.03.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2002] [Accepted: 03/01/2004] [Indexed: 05/24/2023]
Abstract
In this paper we investigate the motion of small particles suspended in a fluid through which an ultrasound field is propagating. The application of the lattice Boltzmann model to this problem is considered using a two dimensional model. Particles in an ultrasound field are observed to move with a mean particle motion. Further, the time-averaged force on a fixed cylinder is computed and found to be in good agreement with a theoretical expression for the radiation force. Simulations are performed with a single particle, although the approach can equally be applied for a larger number of particles.
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10 Severe Neonatal Hyperbilirubinemia: Cause for Concern? Paediatr Child Health 2004. [DOI: 10.1093/pch/9.suppl_a.19a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Abstract
OBJECTIVE To evaluate the usefulness of ponderal index (PI) and related indices of weight and length in identifying asymmetric growth, body thinness and organ asymmetry associated with IUGR. DESIGN Cross sectional study. SETTING Aberdeen Maternity Hospital. POPULATION The population includes term (>/=37 weeks) singleton live births (n= 53,934) between 1986 and 1996, ultrasound measurements in 2522 pregnancies, 712 unselected term pregnancies in 1979/1980 and stillbirths (24-36 weeks) between 1986 and 1995 where the fetus was diagnosed as suffering from acute (n= 73) or chronic (n= 30) anoxic death. METHODS The strength of association between direct measures of IUGR and various indices of weight and length was determined by linear and multiple stepwise linear regression. MAIN OUTCOME MEASURES Weight, length, PI and skinfold thicknesses (triceps, biceps, flank thighs, back) were measured at birth. Abdominal circumference, biparietal diameter and femur length were measured by ultrasound at >/=37 weeks. Ratio of liver, heart and kidney to brain were measured in stillbirths. RESULTS Weight alone was a better predictor of skinfold thickness, abdominal circumference and the ratio of abdominal circumference to biparietal diameter than weight divided by length raised to the power 1, 2, 3 (PI), 4 or 5. The inclusion of gestational age made little difference to the predictive ability of weight for these full term births. Weight, but not PI, was significantly different between the two groups of stillborn fetuses (chronic and acute), which had significantly different (P < 0.001) organ ratios. CONCLUSION Body weight alone was a better predictor of anthropometric ratios, organ asymmetry and measures of thinness at birth thought to be associated with IUGR than the PI. The inclusion of a length term generally reduced the predictive ability with the highest powers resulting in the poorest prediction.
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Abstract
BACKGROUND There is conflicting evidence on the "fetal origins hypothesis" of association between birth weight and adult lung function. This may be due to failure to control for confounding maternal factors influencing birth weight. In the present study access to birth details for adults aged 45-50 years who were documented as children to have asthma, wheezy bronchitis, or no respiratory symptoms provided an opportunity to investigate this association, controlling for maternal factors. METHODS In 2001 the cohort was assessed for current lung function, smoking status, and respiratory symptoms. Birth details obtained from the Aberdeen Maternity and Neonatal Databank recorded birth weight, gestation, parity, and mother's age and height. RESULTS 381 subjects aged 45-50 years were traced and tested for lung function; 323 (85%) had birth details available. A significant linear trend (p<0.01) was observed between birth weight and current forced expiratory volume in 1 second (FEV(1)) and forced vital capacity (FVC) values (adjusted for height, age, sex, weight, deprivation category (Depcat), childhood group, and smoking status). This trend remained significant after adjusting birth weight for gestation, parity, sex, mother's height and weight (p = 0.01). The relationship between birth weight and FEV(1) and FVC remained significant when adjusted for smoking history. There was no association between birth weight and current wheezing symptoms. CONCLUSION There is a positive linear trend between birth weight, adjusted for maternal factors, and lung function in adulthood. The strength of this association supports the "fetal origins hypothesis" that impairment of fetal growth is a significant influence on adult lung function.
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Application of the lattice Boltzmann method to transition in oscillatory channel flow. ACTA ACUST UNITED AC 2003. [DOI: 10.1088/0305-4470/36/10/320] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Prothrombotic genotypes are not associated with pre-eclampsia and gestational hypertension: results from a large population-based study and systematic review. Thromb Haemost 2002; 87:779-85. [PMID: 12038776] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/25/2023]
Abstract
DNA samples collected as part of a large population-based case-control study were genotyped to examine the associations of five prothrombotic gene polymorphisms with pre-eclampsia (PE) and gestational hypertension (GH). The polymorphisms studied were: G1691A in Factor V (Factor V Leiden; FVL), prothrombin G20210A, methylenetetrahydrofolate reductase (MTHFR) C677T, plasminogen activator inhibitor-1 4G/5G and the platelet collagen receptor alpha2beta1 C807T. A group of 404 women who developed PE were retrospectively compared with 303 women with GH and 164 control women. The frequency of genotypes did not differ significantly between cases of PE or GH and controls for any of the five polymorphisms studied. We conclude that these prothrombotic genotypes are not associated with the development of PE or GH in our population. The systematic review supports our conclusion, for all but cases of severe disease. which appear to be associated with FVL and, to a lesser extent, MTHFR C677T. There is little value in antenatal screening for prothrombotic polymorphisms to predict the development of pre-eclampsia or gestational hypertension.
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Assessment of hand-arm vibration syndrome in a northern Ontario base metal mine. CHRONIC DISEASES IN CANADA 2002; 22:88-92. [PMID: 11779422] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
The objective of this study was to determine the prevalence of hand-arm vibration syndrome (HAVS) in 617 workers at a base metal mine in northern Ontario. Workers who were employed at the mine between the years 1989 and 1994 and who continued to live within a 100 km radius of the mine were sent a self-reported questionnaire to identify individuals with possible vibration-induced symptoms in their upper extremities. Of the 162 workers who attended the medical examination, 50% were diagnosed with HAVS, 26% had other diagnoses with some workers having multiple afflictions e.g., both HAVS and carpal tunnel syndrome (CTS). No vibration-induced symptoms were reported in 35% of the workers who were clinically normal. The study was designed to educate, advise, and to make recommendations on the prevention of HAVS. Ongoing commitments to technological improvements, mandatory and regular rest periods, and continuing educational sessions on the syndrome should help to reduce the prevalence of this disease.
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Risk factors for sporadic cases of Escherichia coli O157 infection: the importance of contact with animal excreta. Epidemiol Infect 2001; 127:215-20. [PMID: 11693498 PMCID: PMC2869740 DOI: 10.1017/s0950268801006045] [Citation(s) in RCA: 132] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
To determine environmental risk factors for sporadic E. coli O157 infection in Scotland we undertook a prospective, matched case-control study between 1 October 1996 and 31 March 1999. One hundred and eighty-three cases and 545 matched controls were recruited. Contact with animal faeces (OR = 3.65; 95% CI 1.81, 7.34: P < 0.0005) and likely contact with animal faeces (OR = 4.8; 95% CI 2.42, 9.48; P < 0.0005) emerged as strong risk factors for infection. Certain exposures (mainly food-related) were inversely associated with infection i.e. were statistically protective. Most striking was the consumption of bottled water (OR = 0.28; 95% CI 0.15, 0.52; P < 0.0005). Transmission of E. coli O157 does not occur simply through contaminated food. Members of the public need to be aware of the potential for acquiring E. coli O157 through contamination of the environment with animal faeces so that they may take measures to mitigate their risk.
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Can obstetric complications explain the high levels of obstetric interventions and maternity service use among older women? A retrospective analysis of routinely collected data. BJOG 2001; 108:910-8. [PMID: 11563459 DOI: 10.1111/j.1471-0528.2001.00214.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
OBJECTIVE To determine whether the higher levels of obstetric intervention and maternity service use among older women can be explained by obstetric complications. DESIGN A retrospective analysis of routinely collected data from the Aberdeen Maternity and Neonatal Databank. PARTICIPANTS All residents of Aberdeen city district delivering singleton infants at the Maternity Hospital 1988-1997 (28,484 deliveries). MAIN OUTCOME MEASURES Odds ratios for each intervention in older maternal age groups compared with women aged 20-29. Interventions considered include obstetric interventions (induction of labour, augmentation, epidural use, assisted delivery, caesarean section) and raised maternity service use (more than two prenatal scans, amniocentesis, antenatal admission to hospital, admission at delivery of more than five days, infant resuscitation, and admission to the neonatal unit). METHODS Logistic regression was used to investigate the association between maternal age and the incidence of interventions. The odds ratios for each intervention were then adjusted for relevant obstetric complications and maternal socio-demographic characteristics. RESULTS Levels of amniocentesis, caesarean section, assisted delivery, induction, and augmentation (in primiparae) are all higher among older women. Maternity service use also increases significantly with age: older women are more likely to have an antenatal admission, more than two scans, a hospital stay at delivery of more than five days, and have their baby admitted to a neonatal unit. Controlling for relevant obstetric complications reveals several examples of effect modification, but does not eliminate the age effect for most interventions in most groups of women. CONCLUSIONS Higher levels of intervention among older women are not explained by the obstetric complications we considered.
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Do obstetric complications explain high caesarean section rates among women over 30? A retrospective analysis. BMJ (CLINICAL RESEARCH ED.) 2001; 322:894-5. [PMID: 11302901 PMCID: PMC30584 DOI: 10.1136/bmj.322.7291.894] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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A compact cylindrical Mott electron polarimeter operating with accelerating voltage in the range 20-100 kV. ACTA ACUST UNITED AC 2000. [DOI: 10.1088/0022-3735/18/8/006] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Whither the public health function? THE NEW ZEALAND MEDICAL JOURNAL 2000; 113:448-9. [PMID: 11194767] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
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