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E-cigarettes: A framework for comparative history and policy.
Get PDFBACKGROUND: England, Australia and the United States have approached the regulation of e-cigarettes in very different ways, yet all three countries have appealed to the concept of evidence as underpinning policy responses. We compared these policy responses using a combination of the methodologies of historians and policy scientists in order to elucidate the factors that had influenced policy in each country.
ARGUMENT/ANALYSIS: Each country's evidence and values intersected in different ways, producing very different responses within specific national contexts and histories. Our analysis accordingly emphasized the historical precursors of the policy issues raised by e-cigarettes and placed the policy debate within the context of regulatory bodies and the networks of researchers and advocates who influenced policy. Issues also of importance were the nature of the state; political context; the pre-history of nicotine for smoking cessation; the role of activism and its links with government; the influence of harm reduction ideas from drugs and HIV; and finally, whom policy was perceived to benefit. In the United Kingdom, based on this pre-history of the smoking issue, it was the existing smoker, while in the United States and Australia, protecting children and adolescents has played a central role.
CONCLUSIONS: Structural and historical factors appear to underpin differences in e-cigarette policy development in England, Australia and the United States
Good School Toolkit-Secondary Schools to prevent violence against students: protocol for a pilot cluster randomised controlled trial.
Get PDFINTRODUCTION: No whole-school interventions which seek to reduce physical, sexual and emotional violence from peers, intimate partners and teachers have been trialled with adolescents. Here, we report a protocol for a pilot trial of the Good School Toolkit-Secondary Schools intervention, to be tested in Ugandan secondary schools. Our main objectives are to (1) refine the intervention, (2) to understand feasibility of delivery of the intervention and (3) to explore design parameters for a subsequent phase III trial.
METHODS AND ANALYSIS: We will conduct a pilot cluster randomised controlled trial, with two arms and parallel assignment. Eight schools will be randomly selected from a stratified list of all eligible schools in Kampala and Wakiso Districts. We will conduct a baseline survey and endline survey 18 months after the baseline, with 960 adolescents and 200 teachers. Qualitative data and mixed methods process data collection will be conducted throughout the intervention. Proportion of staff and students reporting acceptability, understanding and implementing with fidelity will be tabulated at endline for intervention schools. Proportions of schools consenting to participation, randomisation and proportions of schools and individual participants completing the baseline and endline surveys will be described in a Consolidated Standards of Reporting Trials diagram.
ETHICS AND DISSEMINATION: The ethical requirements of our project are complex. Full approvals have been received from the Mildmay Ethics Committee (0407-2019), the Uganda National Council for Science and Technology (SS 6020) and the London School of Hygiene & Tropical Medicine (16212). Results of this study will be published in peer-reviewed academic journals, and shared with public bodies, policy makers, study participants and the general public in Uganda.
TRIAL REGISTRATION NUMBER: PACTR202009826515511
Fragment library screening by X-ray crystallography and binding site analysis on thioredoxin glutathione reductase of Schistosoma mansoni.
Get PDFSchistosomiasis is caused by parasites of the genus Schistosoma, which infect more than 200 million people. Praziquantel (PZQ) has been the main drug for controlling schistosomiasis for over four decades, but despite that it is ineffective against juvenile worms and size and taste issues with its pharmaceutical forms impose challenges for treating school-aged children. It is also important to note that PZQ resistant strains can be generated in laboratory conditions and observed in the field, hence its extensive use in mass drug administration programs raises concerns about resistance, highlighting the need to search for new schistosomicidal drugs. Schistosomes survival relies on the redox enzyme thioredoxin glutathione reductase (TGR), a validated target for the development of new anti-schistosomal drugs. Here we report a high-throughput fragment screening campaign of 768 compounds against S. mansoni TGR (SmTGR) using X-ray crystallography. We observed 49 binding events involving 35 distinct molecular fragments which were found to be distributed across 16 binding sites. Most sites are described for the first time within SmTGR, a noteworthy exception being the "doorstop pocket" near the NADPH binding site. We have compared results from hotspots and pocket druggability analysis of SmTGR with the experimental binding sites found in this work, with our results indicating only limited coincidence between experimental and computational results. Finally, we discuss that binding sites at the doorstop/NADPH binding site and in the SmTGR dimer interface, should be prioritized for developing SmTGR inhibitors as new antischistosomal drugs
Impact of cash transfers on the association between prenatal exposures to high temperatures and low birthweight: Retrospective analysis from the LEAP 1000 study.
Get PDFOBJECTIVE: To explore the associations between prenatal temperature exposures and low birthweight (LBW) and modification by cash transfer (CT) receipt. DESIGN: Retrospective cohort study.
SETTING: Five rural districts in Northern Ghana.
POPULATION OR SAMPLE: A total of 3016 infants born to women interviewed as part of the Livelihood Empowerment Against Poverty (LEAP 1000) impact evaluation between 2015 and 2017.
METHODS: Birthweight was collected using household surveys administered to LEAP 1000 eligible women. We used a UNICEF-developed multiple imputation approach to address missingness of birthweight and applied an empirical heaping correction to the multiply imputed birthweight data. Survey data were linked to the European Centre for Medium-Range Weather Forecasts Reanalysis 5-hourly temperature averaged to weeks for 2011-2017 using community centroids. Using distributed-lag nonlinear models, we explored the lag-specific associations between weekly average temperatures greater than 30°C and LBW, and stratified by LEAP 1000 treatment.
MAIN OUTCOME MEASURES: Low birthweight (<2.5 kg).
RESULTS: Twelve percent (n = 365) of infants were LBW; the mean ± SD birthweight was 3.02 ± 0.37 kg. Overall, increasing temperatures were associated with increased odds of LBW, with the greatest odds observed in the 3 weeks before birth (odds ratio 1.005-1.025). These positive associations were even larger among comparison infants and null among treatment infants.
CONCLUSIONS: Our study found increased odds of LBW with high weekly average temperatures throughout pregnancy and the preconception period and demonstrate mitigated effects by the LEAP 1000 CT program. More evidence on the potential of CTs to serve as adaptation interventions in low- and middle-income countries is needed to protect pregnant persons and their infants from the impacts of climate change
Risk of fractures in half a million survivors of 20 cancers: a population-based matched cohort study using linked English electronic health records.
Get PDFBACKGROUND: A history of multiple myeloma, prostate cancer, and breast cancer has been associated with adverse bone health, but associations across a broader range of cancers are unclear. We aimed to compare the risk of any bone fracture and major osteoporotic fractures in survivors of a wide range of cancers versus cancer-free individuals. METHODS: In this population-based matched cohort study, we used electronic health records from the UK Clinical Practice Research Datalink linked to hospital data. We included adults (aged ≥18 years) eligible for linkage, and we restricted the study start to Jan 2, 1998, onwards and applied administrative censoring on Jan 31, 2020. The cancer survivor group included survivors of the 20 most common cancers. Each individual with cancer was matched (age, sex, and general practice) to up to five controls (1:5) who were cancer-free. The primary outcomes were any bone fracture and any major osteoporotic fracture (pelvic, hip, wrist, spine, or proximal humeral fractures) occurring more than 1 year after index date (ie, the diagnosis date of the matched individual with cancer). We used Cox regression models, adjusted for shared risk factors, to estimate associations between cancer survivorship and bone fractures. FINDINGS: 578 160 adults with cancer diagnosed in 1998-2020 were matched to 3 226 404 cancer-free individuals. Crude incidence rates of fractures in cancer survivors ranged between 8·39 cases (95% CI 7·45-9·46) per 1000 person-years for thyroid cancer and 21·62 cases (20·18-23·18) per 1000 person-years for multiple myeloma. Compared with cancer-free individuals, the risk of any bone fracture was increased in 15 of 20 cancers, and of major osteoporotic fractures in 17 of 20 cancers. Effect sizes varied: adjusted hazard ratios (HRs) were largest for multiple myeloma (1·94, 95% CI 1·77-2·13) and prostate cancer (1·43, 1·39-1·47); HRs in the range 1·20-1·50 were seen for stomach, liver, pancreas, lung, breast, kidney, and CNS cancers; smaller associations (HR <1·20) were observed for malignant melanoma, non-Hodgkin lymphoma, leukaemia, and oesophageal, colorectal, and cervical cancers. Increased risks of major osteoporotic fracture were noted most substantially in multiple myeloma (2·25, 1·96-2·58) and CNS (2·12, 1·56-2·87), liver (1·62, 1·01-2·61), prostate (1·60, 1·53-1·67), and lung cancers (1·60, 1·44-1·77). Effect sizes tended to reduce over time since diagnosis but remained elevated for more than 5 years in several cancers, such as multiple myeloma and stomach, lung, breast, prostate, and CNS cancers. INTERPRETATION: Survivors of most types of cancer were at increased risk of bone fracture for several years after cancer, with variation by cancer type. These findings can help to inform mitigation and prevention strategies. FUNDING: Wellcome Trust
Standardised protocol for a prospective international multicentre clinical-based evaluation of point-of-care tests for the screening of genital and extragenital chlamydial and gonococcal infections in men who have sex with men and for the screening of genital chlamydial, gonococcal and Trichomonas vaginalis infections in at risk women.
Get PDFINTRODUCTION: In 2016, WHO estimated there were roughly 374 million new infections among adults of the following four curable sexually transmitted infections (STIs): chlamydia (caused by Chlamydia trachomatis (CT)), gonorrhoea (Neisseria gonorrhoeae (NG)), syphilis (Treponema pallidum) and trichomoniasis (Trichomonas vaginalis (TV)). Accurate point-of-care tests (POCTs) for screening of genital and extragenital CT, NG and TV infections are of great value and have been developed during recent decade. Several tests are commercially available and have shown encouraging performance compared with 'gold-standard' reference tests in laboratory-based studies. However, there is limited data on their clinical performance, including at the POC. Key populations, such as men who have sex with men (MSM), are at higher risk of these STIs at genital and extragenital sites and these STIs are often asymptomatic, especially in extragenital sites and in women. We will conduct a clinical-based evaluation to assess the performance characteristics and acceptability to end-users of molecular-based diagnostic technology for POC/near patient use of the Xpert CT/NG (Cepheid, Sunnyvale, California, USA) test for screening of genital, anorectal and pharyngeal CT and NG infections in MSM and the Xpert CT/NG and Xpert TV (Cepheid, Sunnyvale, California, USA) for screening of genital CT, NG and TV among women at risk for these STIs compared with gold-standard reference nucleic acid amplification tests. This master protocol outlines the overall research approach that will be used in seven countries.
METHOD AND ANALYSES: Consecutive MSM and women at risk presenting at the clinical sites in high, and low- and middle-income countries will be enrolled. The POCTs to be evaluated are Xpert CT/NG and Xpert TV. All procedures will be carried out by trained healthcare staff and tests performed in strict accordance with the manufacturer's instructions. The sensitivity, specificity, positive and negative predictive values for each POCT will be calculated. The study is ongoing with recruitment expected to be completed in all countries by mid-2022 to late-2022.
ETHICS AND DISSEMINATION: Prior to enrolment, this core protocol was independently peer-reviewed and approved by the research project review panel (RP2) of the WHO Department of Sexual and Reproductive Health and Research and by the WHO Ethics Review Committee (ERC). The core protocol has been slightly adapted accordingly to individual countries and adaptations approved by both RP2 and ERC, as well as all relevant institutional review boards at each participating site. Results will be disseminated through peer-reviewed journals and presented at relevant national/international conferences
The impact of pyrethroid-pyriproxyfen and pyrethroid-chlorfenapyr long-lasting insecticidal nets on density of primary malaria vectors Anopheles gambiae s.s. and Anopheles coluzzii in Benin: a secondary analysis of a cluster randomised controlled trial.
Get PDFBACKGROUND: Long-lasting insecticidal nets (LLINs) may have different impacts on distinct mosquito vector species. We assessed the efficacy of pyrethroid-pyriproxyfen and pyrethroid-chlorfenapyr LLINs on the density of Anopheles gambiae s.s. and An. coluzzii compared to pyrethroid-only nets in a three-arm cluster randomised control trial in Benin.
METHODS: Indoor and outdoor collections of adult mosquitoes took place in 60 clusters using human landing catches at baseline and every 3 months for 2 years. After morphological identification, around 15% of randomly selected samples of An. gambiae s.l. were dissected to determine parity, species (using PCR).
RESULTS: Overall, a total of 46,613 mosquito specimens were collected at baseline and 259,250 in the eight quarterly collections post-net distribution. Post-net distribution, approximately 70% of the specimens of An. gambiae s.l. speciated were An. coluzzii, while the rest were mostly composed of An. gambiae s.s. with a small proportion (< 1%) of hybrids (An. gambiae/coluzzii). There was no evidence of a significant reduction in vector density indoors in either primary vector species [An. coluzzii: DR (density ratio) = 0.62 (95% CI 0.21-1.77), p = 0.3683 for the pyrethroid-pyriproxyfen LLIN and DR = 0.56 (95% CI 0.19-1.62), p = 0.2866 for the pyrethroid-chlorfenapyr LLIN, An. gambiae s.s.: DR = 0.52 (95% CI 0.18-1.46), p = 0.2192 for the pyrethroid-pyriproxyfen LLIN and DR = 0.53 (95% CI 0.19-1.46), p = 0.2222 for the pyrethroid-chlorfenapyr]. The same trend was observed outdoors. Parity rates of An. gambiae s.l. were also similar across study arms.
CONCLUSIONS: Compared with pyrethroid-only LLINs, pyrethroid-chlorfenapyr LLINs and pyrethroid-pyriproxyfen LLINs performed similarly against the two primary mosquito species An. gambiae s.s. and An. coluzzii in Benin
Study protocol: a pragmatic, cluster-randomized controlled trial to evaluate the effect of implementation of the Truenat platform/MTB assays at primary health care clinics in Mozambique and Tanzania (TB-CAPT CORE).
Get PDFBACKGROUND: In 2020, the WHO-approved Molbio Truenat platform and MTB assays to detect Mycobacterium tuberculosis complex (MTB) and resistance to rifampicin directly on sputum specimens. This primary health care center-based trial in Mozambique and Tanzania investigates the effect of Truenat platform/MTB assays (intervention arm) combined with rapid communication of results compared to standard of care on TB diagnosis and treatment initiation for microbiologically confirmed TB at 7 days from enrolment.
METHODS: The Tuberculosis Close the Gap, Increase Access, and Provide Adequate Therapy (TB-CAPT) CORE trial employs a pragmatic cluster randomized controlled design to evaluate the impact of a streamlined strategy for delivery of Truenat platform/MTB assays testing at primary health centers. Twenty-nine centers equipped with TB microscopy units were selected to participate in the trial. Among them, fifteen health centers were randomized to the intervention arm (which involves onsite molecular testing using Truenat platform/MTB assays, process process optimization to enable same-day TB diagnosis and treatment initiation, and feedback on Molbio platform performance) or the control arm (which follows routine care, including on-site sputum smear microscopy and the referral of sputum samples to off-site Xpert testing sites). The primary outcome of the study is the absolute number and proportion of participants with TB microbiological confirmation starting TB treatment within 7 days of their first visit. Secondary outcomes include time to bacteriological confirmation, health outcomes up to 60 days from first visit, as well as user preferences, direct cost, and productivity analyses.
ETHICS AND DISSEMINATION: TB-CAPT CORE trial has been approved by regulatory and ethical committees in Mozambique and Tanzania, as well as by each partner organization. Consent is informed and voluntary, and confidentiality of participants is maintained throughout. Study findings will be presented at scientific conferences and published in peer-reviewed international journals.
TRIAL REGISTRATION: US National Institutes of Health's ClinicalTrials.gov, NCT04568954. Registered 23 September 2020
Long-term outcomes after severe childhood malnutrition in adolescents in Malawi (LOSCM): a prospective observational cohort study.
Get PDFBACKGROUND: Research on long-term outcomes of severe childhood malnutrition is scarce. Existing evidence suggests potential associations with cardiometabolic disease and impaired cognition. We aimed to assess outcomes in adolescents who were exposed to severe childhood malnutrition compared with peers not exposed to severe childhood malnutrition.
METHODS: In Long-term Outcomes after Severe Childhood Malnutrition (LOCSM), we followed up adolescents who had 15 years earlier received treatment for severe childhood malnutrition at Queen Elizabeth Central Hospital in Blantyre, Malawi. Adolescents with previous severe childhood malnutrition included in LOCSM had participated in an earlier follow-up study (ChroSAM) at 7 years after treatment for severe childhood malnutrition, where they were compared to siblings and age-matched children in the community without previous severe childhood malnutrition. We measured anthropometry, body composition, strength, glucose tolerance, cognition, behaviour, and mental health during follow-up visits between Sept 9, 2021, and July 22, 2022, comparing outcomes in adolescents exposed to previous severe childhood malnutrition with unexposed siblings and adolescents from the community assessed previously (for ChroSAM) and newly recruited during current follow-up. We used a linear regression model to adjust for age, sex, disability, HIV, and socioeconomic status. This study is registered with the International Standard Randomised Controlled Trial Number Registry (ISRCTN17238083).
FINDINGS: We followed up 168 previously malnourished adolescents (median age 17·1 years [IQR 16·5 to 18·0]), alongside 123 siblings (18·2 years [15·0 to 20·5]), and 89 community adolescents (17·1 years [16·3 to 18·1]). Since last measured 8 years previously, mean height-for-age Z (HAZ) scores had improved in previously malnourished adolescents (difference 0·33 [95% CI 0·20 to 0·46]) and siblings (0·32 [0·09 to 0·55]), but not in community adolescents (difference -0·01 [-0·24 to 0·23]). Previously malnourished adolescents had sustained lower HAZ scores compared with siblings (adjusted difference -0·32 [-0·58 to -0·05]) and community adolescents (-0·21 [-0·52 to 0·10]). The adjusted difference in hand-grip strength between previously malnourished adolescents and community adolescents was -2·0 kg (-4·2 to 0·3). For child behaviour checklist internalising symptom scores, the adjusted difference for previously malnourished adolescents was 2·8 (0·0 to 5·5) compared with siblings and 2·1 (-0·1 to 4·3) compared with community adolescents. No evidence of differences between previously malnourished adolescents and unexposed groups were found in any of the other variables measured.
INTERPRETATION: Catch-up growth into adolescence was modest compared with the rapid improvement seen in childhood, but provides optimism for ongoing recovery of height deficits. We found little evidence of heightened non-communicable disease risk in adolescents exposed to severe childhood malnutrition, although long-term health implications need to be monitored. Further investigation of associated home and environmental factors influencing long-term outcomes is needed to tailor preventive and treatment interventions.
FUNDING: The Wellcome Trust
Effects of community-based interventions for stillbirths in sub-Saharan Africa: a systematic review and meta-analysis.
Get PDFBACKGROUND: Sub-Saharan Africa (SSA) alone contributed to 42% of global stillbirths in 2019, and the rate of stillbirth reduction has remained slow. There has been an increased uptake of community-based interventions to combat stillbirth in the region, but the effects of these interventions have been poorly assessed. Our objectives were to examine the effect of community-based interventions on stillbirth in SSA.
METHODS: In this systematic review and meta-analysis, we searched eight databases (MEDLINE [OvidSP], Embase [OvidSP], Cochrane Central Register of Controlled Trials, Global Health, Science Citation Index and Social Science Citation index [Web of Science Core Collection], CINAHL [EBSCOhost] and Global Index Medicus) and four grey literature sources from January 1, 2000 to July 7, 2023 for relevant studies from SSA. Community-based interventions targeting stillbirths solely or as part of complex interventions, with or without hospital interventions were included, while hospital-only interventions, microcredit schemes and maternity waiting home interventions were excluded. Study quality was assessed using the Cochrane risk of bias and National Heart, Lung and Blood Institute's tools. The study outcome was odds of stillbirth in intervention versus control communities. Pooled odds ratios (ORs) were estimated using random-effects models, and subgroup analyses were performed by intervention type and strategies. Publication bias was evaluated by funnel plot and Egger's test. This study is registered with PROSPERO, CRD42021296623.
FINDINGS: Of the 4223 records identified, seventeen studies from fifteen SSA countries were eligible for inclusion. One study had four arms (community only, hospital only, community and hospital, and control arms), so information was extracted from each arm. Analysis of 13 of the 17 studies which had community-only intervention showed that the odds of stillbirth did not vary significantly between community-based intervention and control groups (OR 0.96; 95% CI 0.78-1.17, I2 = 57%, p ≤ 0.01, n = 63,884). However, analysis of four (out of five) studies that included both community and health facility components found that in comparison with community only interventions, this combination strategy significantly reduced the odds of stillbirth by 17% (OR 0.83; 95% CI 0.79-0.87, I2 = 11%, p = 0.37, n = 244,868), after excluding a study with high risk of bias. The quality of the 17 studies were graded as poor (n = 2), fair (n = 9) and good (n = 6).
INTERPRETATION: Community-based interventions alone, without strengthening the quality and capacity of health facilities, are unlikely to have a substantial effect on reducing stillbirths in SSA.
FUNDING: Nuffield Department of Population Health, Balliol College, the Clarendon Fund, Medical Research Council