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A cornerstone of HIV prevention clinical trials is providing a combination prevention package to all trial participants. The elements included in that standard of care (SoC) package evolve as new prevention modalities are developed. Pre-exposure prophylaxis (PrEP) was recommended by the World Health Organization for persons at high risk of acquiring HIV, but not all countries immediately adopted those recommendations. The South African Medical Research Council (SAMRC) convened a summit to discuss issues relating to SoC and PrEP in HIV prevention clinical trials taking place in lower- to middle-income countries (LMIC). Policymakers, regulators, ethicists, experts in law, researchers, representatives of advocacy groups, and the HIV Vaccine Trials Network (HVTN) presented a framework within which SoC principles could be articulated. A group of subject matter experts presented on the regulatory, ethical, scientific, and historic framework of SoC in clinical trials, focusing on PrEP in South Africa. Summit participants discussed how and when to include new HIV treatment and prevention practices into existing clinical guidelines and trial protocols, as well as the opportunities for and challenges to scaling up interventions. The summit addressed challenges to PrEP provision, such as inconsistent efficacy amongst different populations and various biological, virological, and immunological explanations for this heterogeneity. Advocates and community members propagated the urgent need for accessible interventions that could avert HIV infection. The meeting recommended supporting access to PrEP in HIV prevention trials by (1) developing PrEP access plans for HIV vaccine trials, (2) creating a PrEP fund that would supply PrEP to sites conducting HIV prevention trials via a central procurement mechanism, and (3) supporting the safety monitoring of PrEP. This report summarizes the presentations and discussions from the summit in order to highlight the importance of SoC in HIV prevention clinical trials.
Sujet(s)
Recherche biomédicale , Infections à VIH , Prophylaxie pré-exposition , Infections à VIH/prévention et contrôle , Humains , République d'Afrique du Sud , Norme de soinsRÉSUMÉ
The African Rotavirus Network organised the 12th African Rotavirus Symposium (ARS) from 30 July to 1 August 2019 in Johannesburg, South Africa. The symposium theme "A decade of rotavirus vaccination in Africa - Saving lives and changing the face of diarrhoeal diseases", included sessions aimed at sharing ideas and expertise on prevention and control of diarrhoeal disease in Africa. Inter alia, the delegates reviewed global and regional epidemiological trends on rotavirus diarrhoea, progress and experiences on rotavirus vaccine introduction, including vaccine safety monitoring and impact in Africa, scientific advances in developing newer rotavirus vaccines, surveillance and research on other diarrhoeal pathogens, and providing an enabling environment for networking. Importantly, the 12th ARS served to commemorate the 20th anniversary of the African Rotavirus Network (AfrRN) coinciding with the 50th anniversary of the South African Medical Research Council. Four oral, live-attenuated rotavirus vaccines are currently prequalified by the WHO (Rotarix, RotaTeq, Rotavac and RotaSiil). African countries utilising rotavirus vaccines in routine national immunisation programmes are realising their effectiveness and impact on diarrhoeal disease morbidity. An ~40% reduction in hospitalisations of <5-year-olds with acute gastroenteritis following rotavirus vaccine introduction, was reported between 2006 and 2018 in 92,000 children from the WHO-coordinated African Rotavirus Surveillance Network (AfrRSN) comprising 33 Member States. This was corroborated by a meta-analysis of published data, sourced from January 2000 to August 2018 that reported substantial reductions in rotavirus hospitalisations in countries using rotavirus vaccines. However, it was highlighted that the transition of some countries from Gavi-eligibility and vaccine supply shortfalls present significant challenges to achieving the full impact of rotavirus immunization in Africa. The wide diversity of rotavirus genotypes continues in Africa, with variation observed both geographically and temporally. There is currently no evidence to suggest that the emergence of rotavirus strains not included in the current vaccines do escape vaccine-induced immunity.
Sujet(s)
Infections à rotavirus , Vaccins anti-rotavirus , Rotavirus , Enfant , Enfant d'âge préscolaire , Diarrhée/épidémiologie , Diarrhée/prévention et contrôle , Humains , Nourrisson , Infections à rotavirus/épidémiologie , Infections à rotavirus/prévention et contrôle , République d'Afrique du Sud , VaccinationRÉSUMÉ
The importance of data sharing and biobanking are increasingly being recognised in global health research. Such practices are perceived to have the potential to promote science by maximising the utility of data and samples. However, they also raise ethical challenges which can be exacerbated by existing disparities in power, infrastructure and capacity. The Global Forum on Bioethics in Research (GFBR) convened in Stellenbosch, South Africa in November 2018, to explore the ethics of data sharing and biobanking in health research. Ninety-five participants from 35 countries drew on case studies and their experiences with sharing in their discussion of issues relating to respecting research participants and communities, promoting equitable sharing, and international and national approaches to governing data sharing and biobanking. In this editorial we will briefly review insights relating to each of these three themes.
RÉSUMÉ
BACKGROUND: The five BRICS (Brazil, Russian, Indian, China, and South Africa) countries bear 49% of the world's tuberculosis (TB) burden and they are committed to ending tuberculosis. OBJECTIVES: The aim of this paper is to map the scientific landscape related to TB research in BRICS countries. METHODS: Were combined bibliometrics and social network analysis techniques to map the scientific publications related to TB produced by the BRICS. Was made a descriptive statistical data covering the full period of analysis (1993-2016) and the research networks were made for 2007-2016 (8,366 records). The bubble charts were generated by VantagePoint and the networks by the Gephi 0.9.1 software (Gephi Consortium 2010) from co-occurrence matrices produced in VantagePoint. The Fruchterman-Reingold algorithm provided the networks' layout. FINDINGS: During the period 1993-2016, there were 38,315 peer-reviewed, among them, there were 11,018 (28.7%) articles related by one or more authors in a BRICS: India 38.7%; China 23.8%; South Africa 21.1%; Brazil 13.0%; and Russia 4.5% (The total was greater than 100% because our criterion was all papers with at least one author in a BRICS). Among the BRICS, there was greater interaction between India and South Africa and organisations in India and China had the highest productivity; however, South African organisations had more interaction with countries outside the BRICS. Publications by and about BRICS generally covered all research areas, especially those in India and China covered all research areas, although Brazil and South Africa prioritised infectious diseases, microbiology, and the respiratory system. MAIN CONCLUSIONS: An overview of BRICS scientific publications and interactions highlighted the necessity to develop a BRICS TB research plan to increase efforts and funding to ensure that basic science research successfully translates into products and policies to help end the TB epidemic.
Sujet(s)
Bibliométrie , Recherche biomédicale/statistiques et données numériques , Périodiques comme sujet/statistiques et données numériques , Biais de publication , Tuberculose , Brésil , Chine , Humains , Inde , Russie , République d'Afrique du SudRÉSUMÉ
BACKGROUND The five BRICS (Brazil, Russian, Indian, China, and South Africa) countries bear 49% of the world's tuberculosis (TB) burden and they are committed to ending tuberculosis. OBJECTIVES The aim of this paper is to map the scientific landscape related to TB research in BRICS countries. METHODS Were combined bibliometrics and social network analysis techniques to map the scientific publications related to TB produced by the BRICS. Was made a descriptive statistical data covering the full period of analysis (1993-2016) and the research networks were made for 2007-2016 (8,366 records). The bubble charts were generated by VantagePoint and the networks by the Gephi 0.9.1 software (Gephi Consortium 2010) from co-occurrence matrices produced in VantagePoint. The Fruchterman-Reingold algorithm provided the networks' layout. FINDINGS During the period 1993-2016, there were 38,315 peer-reviewed, among them, there were 11,018 (28.7%) articles related by one or more authors in a BRICS: India 38.7%; China 23.8%; South Africa 21.1%; Brazil 13.0%; and Russia 4.5% (The total was greater than 100% because our criterion was all papers with at least one author in a BRICS). Among the BRICS, there was greater interaction between India and South Africa and organisations in India and China had the highest productivity; however, South African organisations had more interaction with countries outside the BRICS. Publications by and about BRICS generally covered all research areas, especially those in India and China covered all research areas, although Brazil and South Africa prioritised infectious diseases, microbiology, and the respiratory system. MAIN CONCLUSIONS An overview of BRICS scientific publications and interactions highlighted the necessity to develop a BRICS TB research plan to increase efforts and funding to ensure that basic science research successfully translates into products and policies to help end the TB epidemic.
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Humains , Périodiques comme sujet/statistiques et données numériques , Tuberculose , Bibliométrie , Biais de publication , Recherche biomédicale/statistiques et données numériques , République d'Afrique du Sud , Brésil , Chine , Russie , IndeRÉSUMÉ
BACKGROUND: This study was initiated to establish whether any South African ethnomedicinal plants (indigenous or exotic), that have been reported to be used traditionally to repel or kill mosquitoes, exhibit effective mosquito larvicidal properties. METHODS: Extracts of a selection of plant taxa sourced in South Africa were tested for larvicidal properties in an applicable assay. Thirty 3rd instar Anopheles arabiensis larvae were exposed to various extract types (dichloromethane, dichloromethane/methanol) (1:1), methanol and purified water) of each species investigated. Mortality was evaluated relative to the positive control Temephos (Mostop; Agrivo), an effective emulsifiable concentrate larvicide. RESULTS: Preliminary screening of crude extracts revealed substantial variation in toxicity with 24 of the 381 samples displaying 100% larval mortality within the seven day exposure period. Four of the high activity plants were selected and subjected to bioassay guided fractionation. The results of the testing of the fractions generated identified one fraction of the plant, Toddalia asiatica as being very potent against the An. arabiensis larvae. CONCLUSION: The present study has successfully identified a plant with superior larvicidal activity at both the crude and semi pure fractions generated through bio-assay guided fractionation. These results have initiated further research into isolating the active compound and developing a malaria vector control tool.
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Anopheles/effets des médicaments et des substances chimiques , Insecticides/isolement et purification , Insecticides/pharmacologie , Extraits de plantes/isolement et purification , Extraits de plantes/pharmacologie , Plantes médicinales/composition chimique , Rutaceae/composition chimique , Animaux , Évaluation préclinique de médicament/méthodes , Humains , Larve/effets des médicaments et des substances chimiques , République d'Afrique du Sud , Analyse de survieRÉSUMÉ
BACKGROUND: This study was conducted to evaluate whether a selection of South African ethnomedicinal plants included in this study displayed insecticidal properties when screened against adult stages of the mosquito. METHODS: 381 crude extracts of 80 plant taxa in 42 families were sprayed onto ceramic tiles and screened using the cone bio-assay method for insecticide efficacy testing. Blood-fed, female Anopheles arabiensis mosquitoes were exposed to the treated tiles for a period of sixty minutes. Mosquito mortality was monitored for twenty-four hours. RESULTS: Of all the extracts analysed, the highest activity was observed in Ptaeroxylon obliquum (Ptaeroxylaceae) and Pittosporum viridiflorum (Pittosporaceae), a single extract from each, exhibiting more than 50% mortality. A large proportion (81.63%) of the extracts tested displayed low levels of mosquitocidal activity. The remainder of the extracts (17.85%) exhibited no bioactivity (0% mortality). CONCLUSIONS: The screening results have shown that in accordance with WHO standards, none of the crude extracts tested had exhibited greater than 60% mortality against the adult stages of the malaria vector Anopheles arabiensis.
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Anopheles/effets des médicaments et des substances chimiques , Mélanges complexes/pharmacologie , Insecticides/pharmacologie , Dépistage de masse/méthodes , Extraits de plantes/pharmacologie , Animaux , Mélanges complexes/isolement et purification , Femelle , Insecticides/isolement et purification , Extraits de plantes/isolement et purification , République d'Afrique du Sud , Analyse de survieRÉSUMÉ
BACKGROUND: This study was initiated to establish whether any South African ethnomedicinal plants (indigenous or exotic), that have been reported to be used traditionally to repel or kill mosquitoes, exhibit effective mosquito repellent properties. METHODS: Extracts of a selection of South African taxa were tested for repellency properties in an applicable mosquito feeding-probing assay using unfed female Anopheles arabiensis. RESULTS: Although a water extract of the roots of Chenopodium opulifolium was found to be 97% as effective as DEET after 2 mins, time lag studies revealed a substantial reduction in efficacy (to 30%) within two hours. CONCLUSIONS: None of the plant extracts investigated exhibited residual repellencies >60% after three hours.
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Anopheles/effets des médicaments et des substances chimiques , Chenopodium/composition chimique , Insectifuges/pharmacologie , Plantes médicinales/composition chimique , Animaux , Comportement alimentaire/effets des médicaments et des substances chimiques , Femelle , Insectifuges/isolement et purification , Murinae , Racines de plante/composition chimique , Plantes , République d'Afrique du SudRÉSUMÉ
AIM: To investigate the traditional antidiabetic uses of indigenous or naturalised South African plants using an optimised screening and scoring method. MATERIALS AND METHODS: Eleven plant species were screened against Chang liver, 3T3-L1 adipose and C2C12 muscle cells measuring glucose utilisation in all three cell lines and toxicity in the hepatocytes and adipocytes only. A scoring system was devised to aid interpretation of results. RESULTS: Catharanthus roseus results correlated with previously reported in vivo results, with best stimulation of glucose utilisation in hepatocytes. Momordica foetida and Momordica balsamina extracts were active in myocytes but only the latter stimulated glucose utilisation in hepatocytes. Brachylaena discolor gave the best overall results, with all plant parts giving high activity scores and negligible toxicity. In vitro toxicity results for Catharanthus roseus, Vinca major, Momordica balsamina and some Sclerocarya birrea extracts raise concern for chronic use. CONCLUSION: This screening system increases the likelihood of identifying drug candidates using in vitro antidiabetic screening of crude plant extracts, whilst the scoring system aids data interpretation. ETHNOPHARMACOLOGICAL RELEVANCE: The multitude of metabolic steps affected by Type II diabetes offer many drug targets but they complicate in vitro screening to validate traditional uses or find new drug leads from plants.
Sujet(s)
Diabète de type 2/traitement médicamenteux , Hypoglycémiants/pharmacologie , Extraits de plantes/pharmacologie , Plantes médicinales/composition chimique , Cellules 3T3-L1 , Adipocytes/effets des médicaments et des substances chimiques , Adipocytes/métabolisme , Animaux , Lignée cellulaire , Glucose/métabolisme , Hépatocytes/effets des médicaments et des substances chimiques , Hépatocytes/métabolisme , Humains , Hypoglycémiants/isolement et purification , Hypoglycémiants/toxicité , Médecine traditionnelle africaine , Souris , Extraits de plantes/toxicité , République d'Afrique du Sud , Tests de toxicitéRÉSUMÉ
The increasing prevalence and distribution of malaria has been attributed to a number of factors, one of them being the emergence and spread of drug resistant parasites. Efforts are now being directed towards the discovery and development of new chemically diverse antimalarial agents. The present study reports on the in vitro antiplasmodial activity of 134 plant taxa native to or naturalised in South Africa, representing 54 families, which were selected semi-quantitatively using weighted criteria. The plant extracts were tested for in vitro activity against a Plasmodium falciparum strain D10 using the parasite lactate dehydrogenase (pLDH) assay. Of the 134 species assayed, 49% showed promising antiplasmodial activity (IC(50)< or = 10 microg/ml), while 17% were found to be highly active (IC(50)< or = 5 microg/ml). Several plant species and genera were shown for the first time to possess in vitro antiplasmodial activity. These results support a rational rather than random approach to the selection of antiplasmodial screening candidates, and identify a number of promising taxa for further investigation as plant-based antimalarial agents.