Malaria in Africa: Vector Species' Niche Models and Relative Risk Maps

A central theoretical goal of epidemiology is the construction of spatial models of disease prevalence and risk, including maps for the potential spread of infectious disease. We provide three continent-wide maps representing the relative risk of malaria in Africa based on ecological niche models of vector species and risk analysis at a spatial resolution of 1 arc-minute (9 185 275 cells of approximately 4 sq km). Using a maximum entropy method we construct niche models for 10 malaria vector species based on species occurrence records since 1980, 19 climatic variables, altitude, and land cover data (in 14 classes). For seven vectors (Anopheles coustani, A. funestus, A. melas, A. merus, A. moucheti, A. nili, and A. paludis) these are the first published niche models. We predict that Central Africa has poor habitat for both A. arabiensis and A. gambiae, and that A. quadriannulatus and A. arabiensis have restricted habitats in Southern Africa as claimed by field experts in criticism of previous models. The results of the niche models are incorporated into three relative risk models which assume different ecological interactions between vector species. The “additive” model assumes no interaction; the “minimax” model assumes maximum relative risk due to any vector in a cell; and the “competitive exclusion” model assumes the relative risk that arises from the most suitable vector for a cell. All models include variable anthrophilicity of vectors and spatial variation in human population density. Relative risk maps are produced from these models. All models predict that human population density is the critical factor determining malaria risk. Our method of constructing relative risk maps is equally general. We discuss the limits of the relative risk maps reported here, and the additional data that are required for their improvement. The protocol developed here can be used for any other vector-borne disease

Quinine, an old anti-malarial drug in a modern world: role in the treatment of malaria

Quinine remains an important anti-malarial drug almost 400 years after its effectiveness was first documented. However, its continued use is challenged by its poor tolerability, poor compliance with complex dosing regimens, and the availability of more efficacious anti-malarial drugs. This article reviews the historical role of quinine, considers its current usage and provides insight into its appropriate future use in the treatment of malaria. In light of recent research findings intravenous artesunate should be the first-line drug for severe malaria, with quinine as an alternative. The role of rectal quinine as pre-referral treatment for severe malaria has not been fully explored, but it remains a promising intervention. In pregnancy, quinine continues to play a critical role in the management of malaria, especially in the first trimester, and it will remain a mainstay of treatment until safer alternatives become available. For uncomplicated malaria, artemisinin-based combination therapy (ACT) offers a better option than quinine though the difficulty of maintaining a steady supply of ACT in resource-limited settings renders the rapid withdrawal of quinine for uncomplicated malaria cases risky. The best approach would be to identify solutions to ACT stock-outs, maintain quinine in case of ACT stock-outs, and evaluate strategies for improving quinine treatment outcomes by combining it with antibiotics. In HIV and TB infected populations, concerns about potential interactions between quinine and antiretroviral and anti-tuberculosis drugs exist, and these will need further research and pharmacovigilance

Epidemiology of neurodegenerative diseases in sub-Saharan Africa: a systematic review

BACKGROUND:Sub-Saharan African (SSA) countries are experiencing rapid transitions with increased life expectancy. As a result the burden of age-related conditions such as neurodegenerative diseases might be increasing. We conducted a systematic review of published studies on common neurodegenerative diseases, and HIV-related neurocognitive impairment in SSA, in order to identify research gaps and inform prevention and control solutions. METHODS: We searched MEDLINE via PubMed, 'Banque de Donnees de Sante Publique' and the database of the 'Institut d'Epidemiologie Neurologique et de Neurologie Tropicale' from inception to February 2013 for published original studies from SSA on neurodegenerative diseases and HIV-related neurocognitive impairment. Screening and data extraction were conducted by two investigators. Bibliographies and citations of eligible studies were investigated. RESULTS: In all 144 publications reporting on dementia (n=49 publications, mainly Alzheimer disease), Parkinsonism (PD, n=20), HIV-related neurocognitive impairment (n=47), Huntington disease (HD, n=19), amyotrophic lateral sclerosis (ALS, n=15), cerebellar degeneration (n=4) and Lewy body dementia (n=1). Of these studies, largely based on prevalent cases from retrospective data on urban populations, half originated from Nigeria and South Africa. The prevalence of dementia (Alzheimer disease) varied between <1% and 10.1% (0.7% and 5.6%) in population-based studies and from <1% to 47.8% in hospital-based studies. Incidence of dementia (Alzheimer disease) ranged from 8.7 to 21.8/1000/year (9.5 to 11.1), and major risk factors were advanced age and female sex. HIV-related neurocognitive impairment's prevalence (all from hospital-based studies) ranged from <1% to 80%. Population-based prevalence of PD and ALS varied from 10 to 235/100,000, and from 5 to 15/100,000 respectively while that for Huntington disease was 3.5/100,000. Equivalent figures for hospital based studies were the following: PD (0.41 to 7.2%), ALS (0.2 to 8.0/1000), and HD (0.2/100,000 to 46.0/100,000). CONCLUSIONS: The body of literature on neurodegenerative disorders in SSA is large with regard to dementia and HIV-related neurocognitive disorders but limited for other neurodegenerative disorders. Shortcomings include few population-based studies, heterogeneous diagnostic criteria and uneven representation of countries on the continent. There are important knowledge gaps that need urgent action, in order to prepare the sub-continent for the anticipated local surge in neurodegenerative diseases

A produção científica da enfermagem e a utilização da teoria de Madeleine Leininger: revisão integrativa 1985 - 2011 La producción científica de enfermería y la utilización de la teoría de Madeleine Leininger: revisión integradora 1985 - 2011 Scientific nursing production and Madeleine Leininger's theory: integrated review 1985 - 2011

Trata-se de revisão integrativa cujo objetivo foi refletir sobre a utilização da teoria da diversidade e universalidade do cuidado cultural de Madeleine Leininger na produção científica brasileira de enfermagem. Foram consultadas as bases de dados: Base de Dados de Enfermagem, Literatura Latino-americana e do Caribe em Ciências da Saúde e Scientific Electronic Library Online no período amostral de janeiro de 1985 a janeiro de 2011. Foram selecionados 62 artigos dos quais emergiram quatro grupos segundo a semelhança metodológica: 16,12% tratam de relatos de experiência; 45,16%, de processos investigativos; 22,58%, de reflexão e 16,12%, de revisão sobre a teoria de Leininger. Constatou-se que a teoria é utilizada para favorecer a proposta do cuidado holístico em enfermagem e a intenção de conhecer e respeitar a cultura dos clientes para que as ações da enfermeira alcancem o resultado almejado. Suscita valiosa contribuição ao trazer reflexões e delinear orientações para a prática de enfermagem.<br>Esta es una revisión integradora cuyo objetivo fue reflexionar acerca de la utilización de la teoría de la diversidad y universalidad del cuidado cultural de Madeleine Leininger para la producción científica brasileña de enfermería. Fueron consultadas las siguientes bases de datos: Base de Datos de Enfermería, Literatura Latinoamericana y de Caribe en Ciencias de la Salud y Scientific Electronic Library Online en el periodo de enero de 1985 hasta enero de 2011. Fueron seleccionados 62 artículos de los cuales se ha elegido cuatro grupos de acuerdo a la semejanza metodológica: 16,12% de relatos de experiencia; 45,16% de procesos investigativos; 22,58 % de reflexión y 16,12% de revisión sobre la teoría de Leininger. Se constató que se utiliza la teoría para favorecer la propuesta del cuidado holístico en enfermería y la intención de conocer y respetar la cultura de los clientes para que las acciones de la enfermera lleguen al resultado esperado. Suscita gran contribución porque trae reflexiones y delinea orientaciones para la práctica de enfermería.<br>It is an integrated review which objectified to think over the use of Madeleine Leininger's theory of cultural care diversity and universality for the Brazilian scientific nursing production. The following databases were searched: Nursing Database, Latin-American and Caribbean Health Science Literature, and Scientific Electronic Library Online in the sampling period from January/1985 to January/2011. Sixty-two articles were selected, emerging four groups according to their methodological resemblance: 16,12% are experience accounts; 45,16% are investigative processes; 22,58 % are reflections and 16,12% are review on Leininger's theory. It was found that the theory is used to favors the proposal for nursing holistic care and its purpose of getting to know and respect clients' culture so that nursing actions accomplish the targeted results. It fosters invaluable contribution as it brings about reflections and designs some guidelines for nursing practice

One-pot synthesis, characterization, and antioxidant capacity of sulfur- and oxygen-substituted 1,4-naphthoquinones and a structural study

In the present study, we reported the one-pot synthesis of S,S- and S,O-substituted 1,4-naphthoquinones, their structural studies, and investigation of their antioxidant activity. The multicomponent reactions of 2,3-dichloro-1,4-naphthoquinone with sulfur- and oxygen-containing nucleophiles were investigated to obtain highly functionalized S,S- and S,O-substituted 1,4-naphthoquinone derivatives. All new compounds were characterized on the basis of H-1, F-19, and C-13 nuclear magnetic resonance spectroscopy, mass spectrometry, and Fourier transform infrared spectroscopy. Crystal structure of 2,3-dihydro-2-(hydroxymethyl)naphtho[2,3-b]-1,4-oxathiin-5,10-dione was determined by X-ray diffraction method. The synthesized compounds were screened for their antioxidant capacity and free radical scavenging activity using the cupric reducing antioxidant capacity method and DPPH method, respectively. 3-Chloro-2-[3-(3-chloro-1,4-dihydro-1,4-dioxonaphthalen-2-yloxy)propylsulfanyl]-1,4-naphthoquinone shows the highest antioxidant capacity with 0.63 cupric reducing antioxidant capacity-trolox equivalent antioxidant capacity coefficient