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Chemical conversion of the extract of natural resources is a very attractive way to expand the chemical space to discover bioactive compounds. In order to search for new medicines to treat parasitic diseases that cause high morbidity and mortality in affected countries in the world, the ethyl acetate extract from the rhizome of Alpinia galanga (L.) has been chemically converted by epoxidation using dioxirane generated in situ. The biological activity of chemically converted extract (CCE) of A. galanga (L.) significantly increased the activity against Leishmania major up to 82.6 ± 6.2 % at 25 µg/mL (whereas 2.7 ± 0.8% for the original extract). By bioassay-guided fractionation, new phenylpropanoids (1-6) and four known compounds, hydroquinone (7), 4-hydroxy(4-hydroxyphenyl)methoxy)benzaldehyde (8), isocoumarin cis 4-hydroxymelein (9), and (2S,3S,6R,7R,9S,10S)-humulene triepoxide (10) were isolated from CCE. The structures of isolated compounds were determined by spectroscopic analyses of 1D and 2D NMR, IR, and MS spectra. The most active compound was hydroquinone (7) with IC50 = 0.37 ± 1.37 µg/mL as a substantial active principle of CCE. In addition, the new phenylpropanoid 2 (IC50 = 27.8 ± 0.34 µg/mL) also showed significant activity against L. major compared to the positive control miltefosine (IC50 = 7.47 ± 0.3 µg/mL). The activities of the isolated compounds were also evaluated against Plasmodium falciparum, Trypanosoma brucei gambisense and Trypanosoma brucei rhodeisense. Interestingly, compound 2 was selectively active against trypanosomes with potent activity. To the best of our knowledge, this is the first report on the bioactive "unnatural" natural products from the crude extract of A. galanga (L.) by chemical conversion and on its activities against causal pathogens of leishmaniasis, trypanosomiasis, and malaria.
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Alpinia/química , Antimaláricos , Extractos Vegetales/química , Plasmodium falciparum/crecimiento & desarrollo , Propanoles , Trypanosoma brucei gambiense/crecimiento & desarrollo , Trypanosoma brucei rhodesiense/crecimiento & desarrollo , Antimaláricos/química , Antimaláricos/aislamiento & purificación , Antimaláricos/farmacología , Propanoles/química , Propanoles/aislamiento & purificación , Propanoles/farmacología , Tripanocidas/química , Tripanocidas/aislamiento & purificación , Tripanocidas/farmacologíaRESUMEN
Objective: To investigate the magnitude of urogenital schistosomiasis and determinants of transmission among adolescents and young adults in Itilima district, Simiyu region, Northern Tanzania. Methods: A quantitative cross-sectional study was carried out using probability sampling strategies to select 433 secondary school students from five schools among the five wards of Itilima district, an area endemic for urogenital schistosomiasis. A self-administered structured questionnaire was used to gather data on determinants, and urine samples were examined for macrohaematuria and the presence of Schistosoma haematobium using the standard urine filtration technique. Data analysis was performed using descriptive statistics, Chi-squared test and logistic regression. Results: The overall prevalence rates of S. haematobium infection and macrohaematuria among adolescents and young adults were 15.9% and 3%, respectively, with the majority of individuals being lightly infected (85.5%). The determinants for urogenital schistosomiasis among the adolescents and young adults in Itilima district were: being in Form I [adjusted odds ratio (aOR) 2.42, 95% confidence interval (CI) 1.16-11.8; P=0.018]; being resident in Sasago ward (aOR 5.57, 95% CI 1.98-15.67; P=0.001) or Budalabujiga ward (aOR 2.99, 95% CI 1.04-8.56; P=0.042); having positive attitudes towards urogenital schistosomiasis (aOR 3.14, 95% CI 1.27-7.72; P=0.013); swimming in rivers (aOR 1.92, 95% CI 1.06-3.50; P=0.032); and urinating in water bodies (aOR 1.68, 95% CI 1.05-2.69; P=0.032). Conclusions: Urogenital schistosomiasis is prevalent among adolescents and young adults, and serves as a reservoir for transmission of S. haematobium. Preventive chemotherapy campaigns should be extended to adolescents and young adults, and integrated with regular screening, health education and an adequate water supply.
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Rabies is an important zoonosis in Ethiopia, where lack of research is cited as a constraint to implementation of the national rabies control strategy. We conducted a systematic review of publications and theses on rabies in Ethiopia, to document research gaps and areas of knowledge saturation in relation to geographic and species focus, methods and findings. We also examined funding sources and extent of local researcher participation. After screening titles and abstracts, the full text of 119 publications was included in data extraction. More than 40% of publications involved data collection in one region (Oromia); no publications reported findings from Benishangul-Gumuz, Dire Dawa or Gambella. Dogs and wildlife (especially Canis simensis) were the focus of research in 45% and 24% publications, respectively. Descriptive epidemiology (N = 39 publications), ethno-medicine/-pharmacology (N = 17) and knowledge, attitude, and practice surveys (KAP, N = 15) were amongst the most common study designs, while studies involving economic methods (N = 3) and experimental epidemiology to test interventions (N = 3) were under-represented. Incidence surveys (N = 9) commonly used post-exposure prophylaxis administration in humans as a proxy for exposure without laboratory confirmation of the rabies status of the animal. KAP surveys tended to highlight reasonable levels of knowledge of rabies and poor practices, including overreliance on medicinal plants. International researchers were the first or last (senior) author on 42% and 58% of publications, respectively, most of which were funded by international organizations (45/72 publications reporting funding source). Based on this systematic review, we suggest more applied research is needed to address gaps in laboratory surveillance (including in humans, domestic and wild animals); identify effective ways to overcome socio-cultural and other barriers to accessing effective rabies treatments; inform best approaches to incentivizing mass dog vaccination programs; and generate local estimates of the cost-benefit and cost-effectiveness of different control strategies to improve financing and political buy-in for rabies control in Ethiopia.
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BACKGROUND: Strongyloidiasis is a parasitic disease that mainly affects humans and is caused by a roundworm called Strongyloides stercoralis. It is endemic in humid tropical regions that include Africa, Latin America and Southern Asia. Among the public health important soil-transmitted helminths (STHs) classified as neglected tropical diseases, S. stercoralis is the most neglected. A study of schistosomiasis and STHs mapping was conducted and S. stercoralis larvae were detected using the utilized diagnostic method; thus, this current study described the prevalence and risk factors of S. stercoralis infection in districts of Sabach Sanjal and Upper Badibou in The Gambia. METHODS: The cross-sectional study enrolled 851 schoolchildren, ages 7 to 14 years old. The participants were enrolled from 17 schools in Sabach Sanjal and Upper Badibou Districts. The WHO random sampling technique n/50 (25 boys and 25 girls) was used. Stool samples were collected from each participant and Kato-Katz smear method was used to screen for S. stercoralis infection. RESULTS: Out of the total 851 pupils, 76 pupils (8.9%) were positive for S. stercoralis infection. The mean age of infected persons was 10.1 years (±2.2). The prevalence of infection was higher among females (9.2%) than males (8.7%). Rates of infection for age categories 7-10 years and 11-14 years were 12.4% and 4.2%, respectively. Rates of infection by districts were 12.3% for Sabach Sanjal and 7.1% for Upper Badibou. Schoolchildren from Sabach Sanjal were 1.6 times more likely to have strongyloidiasis compared to those from Upper Badibou (aOR = 1.64, p-value = 0.058). Schoolchildren aged 7-10 years were 3.2 times more likely to have strongyloidiasis infection compared to the 11-14-year-olds (aOR = 3.20, p-value <0.001). Schoolchildren who 'sometimes' have water or tissue after defaecation have more infection rate compared to those who 'always' have water or tissue after defaecation. However, this difference was not statistically significant (aOR = 1.36, p-value = 0.308). CONCLUSION: The study revealed the prevalence of strongyloidiasis in Sabach Sanjal and Upper Badibou districts of The Gambia. Kato-Katz technique might be inadequate for detecting S. stercoralis; thus, more studies are needed to determine the true prevalence of the disease in these two districts through the combined use of highly sensitive techniques such as Baermann, Koga Agar Culture and polymerase chain reaction.
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INTRODUCTION: In Bangladesh, the prevention and control strategy of soil-transmitted helminthiasis (STHs) is based on the mass drug administration (MDA) program. Despite bi-annual MDA since 2008, the reported compliance is still below the target, and the STH prevalence is high in several areas. This study was done to assess the feasibility and barriers of integrating health education (HE) intervention to achieve the target MDA compliance in the local context of Bangladesh. MATERIALS AND METHODS: A mixed-method study, utilizing PRISM (Practical Robust Implementation Sustainability Model) framework, was conducted between July 2017 to March 2018 in Dhaka and Sylhet divisions of Bangladesh. A total of 640 school-aged children selected from four different schools were divided into intervention and control groups. Eight focus group discussions (FGDs) and eight in-depth interviews (IDIs) were also conducted among 56 adults, including parents of school-aged children, school teachers, and health officers. RESULTS: Quantitative findings revealed that HE intervention had a significant role (P < .05) to improve the mean knowledge score in the intervention group (3.35) compared to the control group (0.29). STH preventive behaviours and MDA participating attitudes were also significantly increased in the intervention group (P < .05) compared to the control group. Some of the major barriers associated with HE integration identified in the qualitative study were budget deficiencies, inadequate training of program implementers, and information gaps. In contrast, the school environment and positive community attitudes were observed as supportive factors for the integration of HE. CONCLUSION: Increased knowledge score and behaviour changes due to HE intervention demonstrated in this study hint that integration of HE with MDA is feasible and can be promising to promote MDA compliance and to reduce STH prevalence in this setting. However, the allocation of adequate budget, as well as coordination and collaboration with local political context, should be addressed for the sustainability of integration.
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Current efforts for the prevention of malaria have resulted in notable reductions in the global malaria burden; however, they are not enough. Good hygiene is universally considered one of the most efficacious and straightforward measures to prevent disease transmission. This work analyzed whether improved drinking water and sanitation (WS) conditions were associated with a decreased risk of malaria infection. Data were acquired through surveys published between 2006 and 2018 from the Demographic and Health Program in sub-Saharan Africa (SSA). Multiple logistic regression was used for each national survey to identify the associations between WS conditions and malaria infection diagnosed by microscopy or a malaria rapid diagnostic test (RDT) among children (0-59â¯months), with adjustments for age, gender, indoor residual spraying (IRS), insecticide-treated net (ITN) use, house quality, and the mother's highest educational level. Individual nationally representative survey odds ratios (ORs) were combined to obtain a summary OR using a random-effects meta-analysis. Among the 247,440 included children, 18.8% and 24.2% were positive for malaria infection based on microscopy and RDT results, respectively. Across all surveys, both unprotected water and no facility users were associated with increased malaria risks (unprotected water: aOR 1.17, 95% CI 1.07-1.27, Pâ¯=â¯0.001; no facilities: aOR 1.35, 95% CI 1.24-1.47, Pâ¯<â¯0.001; respectively), according to microscopy, whereas the odds of malaria infection were 48% and 49% less among piped water and flush-toilet users, respectively (piped water: aOR 0.52, 95% CI 0.45-0.59, Pâ¯<â¯0.001; flush toilets: aOR 0.51, 95% CI 0.43-0.61, Pâ¯<â¯0.001). The trends of individuals diagnosed by RDT were consistent with those of individuals diagnosed by microscopy. Risk associations were more pronounced among children with a "nonpoor" socioeconomic status who were unprotected water or no facility users. WS conditions are a vital risk factor for malarial infection among children (0-59â¯months) across SSA. Improved WS conditions should be considered a potential intervention for the prevention of malaria in the long term.
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Neglected tropical diseases (NTDs) affect people in the bottom billion poorest in the world. These diseases are concentrated in rural areas, conflict zones and urban slums in Africa and other tropical areas. While the World Health Organization recognizes seventeen priority NTDs, the list of conditions present in Africa and elsewhere that are eligible to be classified as NTDs is much longer. Although NTDs are generally marginalized, their associated neurological burden has been almost completely disregarded. However, reports indicate that trichuriasis, schistosomiasis and hookworm infection, among others, cause impairments in memory and cognition, negatively affecting school attendance rates and educational performance particularly among children, as well as agricultural productivity among adults. Consequently, the neurological impairments have substantial influence on education and economic productivity, thus aggravating and perpetuating poverty in affected societies. However, inadequate research, policy and public health attention has been paid to the neurological burdens associated with NTDs. In order to appropriately address these burdens, we recommend the development of policy interventions that focus on the following areas: (i) the introduction of training programs to develop the capacity of scientists and clinicians in research, diagnostic and treatment approaches (ii) the establishment of competitive research grant schemes to fund cutting-edge research into these neurological impairments, and (iii) the development of public health interventions to improve community awareness of the NTD-associated neurological problems, possibly enhancing disease prevention and expediting treatment.
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As a part of the lymphatic filariasis (LF) transmission assessment survey (TAS)/soil-transmitted helminths (STH) prevalence survey in Western Division of Fiji, a pilot screen for Strongyloides stercoralis (SS) in school children was undertaken using a combination of the Baermann concentration (BC) method and real-time PCR assays. Using BC, faecal samples collected from 111 children of 7 schools were examined. A single child was positive for larvae of SS and underwent a clinical examination finding an asymptomatic infection. Other members of this child's household were screened with BC, finding none infected. Aliquots of 173 faecal samples preserved in ethanol originating from all schools were examined by real-time PCR, and the prevalence of SS infection was 3.5%. Our study confirms the existence of SS infection on Fiji and showed that assessing SS prevalence alongside TAS/STH survey is a convenient access platform, allowing introduction of other surveillance techniques such as BC and real-time PCR.