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1.
PLoS Negl Trop Dis ; 16(3): e0010115, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35263327

RESUMO

BACKGROUND: Evidence from recent studies in Schistosoma mansoni-endemic areas show an age-associated immunity that is positively correlated with IgE titres to Schistosoma mansoni-specific tegumental allergen-like protein 1 (SmTAL1). The structural homology between SmTAL1 and the S. haematobium-specific TAL1 (ShTAL1) has been verified, yet it remains unclear whether similar age- and immune-associated trends characterize ShTAL1. This community-based intervention study was conducted to assess whether ShTAL1IgE responses post-treatment with praziquantel (PZQ) might be associated with a reduced risk to re-infection with S. haematobium. METHODOLOGY/PRINCIPAL FINDINGS: This study was conducted at Agona Abodom, Central Region, Ghana, and involved 114 participants aged 6 to 55 years. EDTA blood samples were collected at baseline and 7 weeks after PZQ treatment (Follow-up). Baseline and Follow-up titres of specific IgG1, IgG4, and IgE antibodies to the S. haematobium-specific adult worm antigen (ShAWA), the Sh-specific soluble egg antigen (ShSEA), and the Sh-specific tegumental-allergen-like 1 protein (ShTAL1) in plasma samples were measured using sandwich ELISA. Participants at both time points also provided stool and urine for helminth egg detection by microscopy. Prevalence of S. haematobium at baseline was 22.80%, and decreased to 3.50% at Follow-up. The egg reduction rate (ERR) was 99.87%. Overall plasma levels of ShTAL1-IgE increased 7 weeks post-PZQ treatment, and with increasing age; whiles S. haematobium infection prevalence and intensity decreased. For S. haematobium-infected participants who were egg-negative at Follow-up (N = 23), minimal median levels of ShTAL1-IgE were observed for all age groups prior to treatment, whilst median levels increased considerably among participants aged 12 years and older at Follow-up; and remained minimal among participants aged 11 years or less. In the univariate analysis, being aged 12 years or older implied an increased likelihood for ShTAL1-IgE positivity [12-14 years (cOR = 9.64, 95% CI = 2.09-44.51; p = 0.004); 15+ years (cOR = 14.26, 95% CI = 3.10-65.51; p = 0.001)], and this remained significant after adjusting for confounders [12-14 years (aOR = 22.34, 95% CI = 2.77-180.14; p = 0.004); ≥15 years (aOR = 51.82, 95% CI = 6.44-417.17; p < 0.001)]. Conversely, median ShTAL1-IgG4 titres were hardly detectible at Follow-up. CONCLUSIONS/SIGNIFICANCE: These findings demonstrate that increased IgE levels to ShTAL1 7 weeks after PZQ treatment could be associated with a reduced risk to re-infection, and adds to the large body of evidence suggesting a protective role of the treatment-induced ShTAL1 antigen in schistosomiasis infections. It was also quite clear from this work that apart from being persistently S. haematobium-positive, elevated ShTAL1-IgG4 levels at Follow-up could be indicative of susceptibility to re-infection. These outcomes have important implications in vaccine development, and in shifting the paradigm in mass chemotherapy programmes from a 'one-size-fits-all' approach to more sub-group-/participant-specific strategies in endemic areas.


Assuntos
Anti-Helmínticos , Esquistossomose Urinária , Alérgenos , Animais , Anti-Helmínticos/uso terapêutico , Feminino , Gana/epidemiologia , Humanos , Imunoglobulina E , Imunoglobulina G , Masculino , Praziquantel/uso terapêutico , Reinfecção , Schistosoma haematobium , Schistosoma mansoni , Esquistossomose Urinária/tratamento farmacológico , Esquistossomose Urinária/epidemiologia , Resultado do Tratamento
2.
PLoS Negl Trop Dis ; 13(3): e0007235, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30908481

RESUMO

Visceral leishmaniasis (VL) is a major problem worldwide and causes significant morbidity and mortality. Existing drugs against VL have limitations, including their invasive means of administration long duration of treatment regimens. There are also concerns regarding increasing treatment relapses as well as the identification of resistant clinical strains with the use of miltefosine, the sole oral drug for VL. There is, therefore, an urgent need for new alternative oral drugs for VL. In the present study, we show the leishmanicidal effect of a novel, oral antimalarial endoperoxide N-251. In our In vitro studies, N-251 selectively and specifically killed Leishmania donovani D10 amastigotes with no accompanying toxicity toward the host cells. In addition, N-251 exhibited comparable activities against promastigotes of L. donovani D10, as well as other L. donovani complex parasites, suggesting a wide spectrum of activity. Furthermore, even after a progressive infection was established in mice, N-251 significantly eliminated amastigotes when administered orally. Finally, N-251 suppressed granuloma formation in mice liver through parasite death. These findings indicate the therapeutic effect of N-251 as an oral drug, hence suggest N-251 to be a promising lead compound for the development of a new oral chemotherapy against VL.


Assuntos
Antimaláricos/administração & dosagem , Antiprotozoários/administração & dosagem , Leishmania donovani/efeitos dos fármacos , Leishmaniose Visceral/tratamento farmacológico , Compostos de Espiro/administração & dosagem , Tetraoxanos/administração & dosagem , Animais , Antimaláricos/farmacologia , Antiprotozoários/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Modelos Animais de Doenças , Leishmania donovani/fisiologia , Leishmaniose Visceral/patologia , Fígado/patologia , Camundongos Endogâmicos BALB C , Compostos de Espiro/farmacologia , Tetraoxanos/farmacologia , Resultado do Tratamento
3.
Anal Cell Pathol (Amst) ; 2018: 4675380, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30631746

RESUMO

Schistosomiasis is a neglected tropical disease that affects 200 million people and accounts for 100,000 deaths annually. In endemic geographical areas, schistosomiasis has been implicated as an etiological agent in the pathogenesis of bladder, colorectal, and renal carcinoma largely due to Schistosoma eggs in tissues that comes with chronic infection. Several studies have also reported cases of association between Schistosoma infection and prostate cancer. The possible causal association is however poorly understood. We hypothesized in this study that infection of the prostate cells with Schistosoma spp promotes cancer. Urine samples from individuals living in Galilea, a schistosomiasis endemic community in the Ga South District of Ghana, were collected and screened for Schistosoma infection via microscopy and multiplex PCR. Soluble egg antigens (SEA) were prepared from Schistosoma egg-positive urine samples and assessed for the ability to induce cancer-like phenotypes including excessive proliferation, oxidative stress (reduced glutathione (GSH) depletion), and diminished apoptosis in cultured human prostate (PNT2) cells. Molecular analysis revealed infecting schistosome species to be S. haematobium and S. mansoni. Prostate cell proliferation was significantly induced by 12.5 µg/ml SEA (p = 0.029). Also, SEA dose-dependently depleted cellular GSH. Flow cytometric analysis and fluorescence staining revealed that SEA dose-dependently diminished apoptosis, significantly, in prostate cells. Findings of this study suggest that schistosome infection may play a role in the pathogenesis of prostate cancer. In vivo studies are however needed to confirm this association.


Assuntos
Antígenos de Helmintos/metabolismo , Carcinogênese/patologia , Óvulo/metabolismo , Próstata/patologia , Próstata/parasitologia , Schistosoma/imunologia , Animais , Apoptose , Linhagem Celular , Núcleo Celular/metabolismo , Proliferação de Células , Feminino , Glutationa/metabolismo , Humanos , Masculino , Estresse Oxidativo , Prevalência , Esquistossomose/epidemiologia , Esquistossomose/patologia , Esquistossomose/urina
4.
Ocul Immunol Inflamm ; 25(5): 678-684, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27081842

RESUMO

PURPOSE: To evaluate associations between IFN-γ +874T/A and TNF-α-308G/A polymorphism with the development of Toxoplasma retinochoroiditis. METHODS: By ARMS-PCR, a cross-sectional genetic study involving 30 patients with Toxoplasma retinochoroiditis and 87 controls was carried out. RESULTS: IFN-γ +874: by comparing with the AA genotype, individuals with the TT genotype had a 3.4 odds ratio (OR); AT had a 1.6 OR; and the T allele had a higher OR (1.6), indicating a likely susceptibility of IFN-γ +874T to the infection, though the overall distribution was not significant (p = 0.259). For TNF-α-308G/A, individuals with both GA and AA genotypes had lower ORs when compared with the GG genotype, implying the A allele could confer protection against Toxoplasma ocular lesions. CONCLUSIONS: IFN-γ +874T allele may increase the risk of ocular lesions in Toxoplasma infection. The principle of natural selection seems to also play a role. The less common TNF-308A allelic form could be protective against the development of Toxoplasma ocular infection.


Assuntos
Coriorretinite/genética , Interferon gama/genética , Polimorfismo de Nucleotídeo Único , Toxoplasmose Ocular/genética , Fator de Necrose Tumoral alfa/genética , Adulto , Coriorretinite/diagnóstico , Coriorretinite/epidemiologia , Estudos Transversais , Feminino , Amplificação de Genes , Frequência do Gene , Genótipo , Gana/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Reação em Cadeia da Polimerase , Toxoplasmose Ocular/diagnóstico , Toxoplasmose Ocular/epidemiologia
5.
Trials ; 17: 37, 2016 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-26792672

RESUMO

BACKGROUND: 'Home-grown' school feeding programmes are complex interventions with the potential to link the increased demand for school feeding goods and services to community-based stakeholders, including smallholder farmers and women's groups. There is limited rigorous evidence, however, that this is the case in practice. This evaluation will examine explicitly, and from a holistic perspective, the simultaneous impact of a national school meals programme on micronutrient status, alongside outcomes in nutrition, education and agriculture domains. The 3-year study involves a cluster-randomised control trial designed around the scale-up of the national school feeding programme, including 116 primary schools in 58 districts in Ghana. The randomly assigned interventions are: 1) a school feeding programme group, including schools and communities where the standard government programme is implemented; 2) 'home-grown' school feeding, including schools and communities where the standard programme is implemented alongside an innovative pilot project aimed at enhancing nutrition and agriculture; and 3) a control group, including schools and households from communities where the intervention will be delayed by at least 3 years, preferably without informing schools and households. Primary outcomes include child health and nutritional status, school participation and learning, and smallholder farmer income. Intermediate outcomes along the agriculture and nutrition pathways will also be measured. The evaluation will follow a mixed-method approach, including child-, household-, school- and community-level surveys as well as focus group discussions with project stakeholders. The baseline survey was completed in August 2013 and the endline survey is planned for November 2015. RESULTS: The tests of balance show significant differences in the means of a number of outcome and control variables across the intervention groups. Important differences across groups include marketed surplus, livestock income, per capita food consumption and intake, school attendance, and anthropometric status in the 2-5 and 5-15 years age groups. In addition, approximately 19 % of children in the target age group received some form of free school meals at baseline. CONCLUSION: Designing and implementing the evaluation of complex interventions is in itself a complex undertaking, involving a multi-disciplinary research team working in close collaboration with programme- and policy-level stakeholders. Managing the complexity from an analytical and operational perspective is an important challenge. The analysis of the baseline data indicates that the random allocation process did not achieve statistically comparable treatment groups. Differences in outcomes and control variables across groups will be controlled for when estimating treatment effects. TRIAL REGISTRATION NUMBER: ISRCTN66918874 (registered on 5 March 2015).


Assuntos
Fenômenos Fisiológicos da Nutrição do Adolescente , Agricultura , Fenômenos Fisiológicos da Nutrição Infantil , Serviços de Alimentação , Estado Nutricional , Avaliação de Programas e Projetos de Saúde , Projetos de Pesquisa , Instituições Acadêmicas , Adolescente , Criança , Pré-Escolar , Análise Custo-Benefício , Coleta de Dados , Educação , Gana , Humanos , Micronutrientes , Tamanho da Amostra
6.
Food Nutr Bull ; 36(3): 264-75, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26385950

RESUMO

BACKGROUND: Nutritional anemia is a public health problem among Ghanaian schoolchildren. There is need to employ dietary modification strategies to solve this problem through school and household feeding programs. OBJECTIVE: To evaluate the effectiveness of cowpea-based food containing fish meal served with vitamin C-rich drink to improve iron stores and hemoglobin concentrations in Ghanaian schoolchildren. METHODS: The study involved cross-sectional baseline and nutrition intervention phases. There were 150 participants of age 6 to 12 years. They were randomly assigned to 3 groups, fish meal -vitamin C (n = 50), vitamin C (n = 50), and control (n = 50), and given different cowpea-based diets for a 6-month period. Height and weight measurements were done according to the standard procedures, dietary data were obtained by 24-hour recall and food frequency questionnaire, hemoglobin concentrations were determined by Hemocue Hemoglobinometer, and serum ferritin and complement-reactive protein (CRP) were determined by enzyme-linked immunosorbent assay. Participants' blood samples were examined for malaria parasitemia and stools for helminthes using Giemsa stain and Kato-Katz techniques, respectively. RESULTS: Mean ferritin concentration was not significantly different among groups. End line mean or change in hemoglobin concentrations between fish meal-vitamin C group (128.4 ± 7.2/8.3 ± 10.6 g/L) and control (123.1 ± 6.6/4.2 ± 10.4 g/L) were different, P < .05. Change in prevalence of anemia in fish meal-vitamin C group (19.5%) was different compared to those of vitamin C group (9.3%) and the control (12.2%). Levels of malaria parasitemia and high CRP among study participants at baseline and end line were 58% and 80% then 55% and 79%, respectively. Level of hookworm infestation was 13%. CONCLUSION: Cowpea-based food containing 3% fish meal and served with vitamin C-rich drink improved hemoglobin concentration and minimized the prevalence of anemia among the study participants.


Assuntos
Anemia Ferropriva/prevenção & controle , Alimentos Fortificados , Malária/epidemiologia , Anemia Ferropriva/sangue , Animais , Ácido Ascórbico/administração & dosagem , Bebidas , Proteína C-Reativa/metabolismo , Criança , Estudos Transversais , Feminino , Ferritinas/sangue , Peixes , Gana/epidemiologia , Hemoglobinas , Humanos , Masculino , Serviços de Saúde Escolar , Inquéritos e Questionários , Resultado do Tratamento , Verduras
7.
Bioorg Med Chem Lett ; 25(15): 3030-3, 2015 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-26048790

RESUMO

Human African trypanosomiasis (HAT), commonly known as sleeping sickness has remained a serious health problem in many African countries with thousands of new infected cases annually. Chemotherapy, which is the main form of control against HAT has been characterized lately by the viewpoints of toxicity and drug resistance issues. Recently, there have been a lot of emphases on the use of medicinal plants world-wide. Morinda lucida Benth. is one of the most popular medicinal plants widely distributed in Africa and several groups have reported on its anti-protozoa activities. In this study, we have isolated one novel tetracyclic iridoid, named as molucidin, from the CHCl3 fraction of the M. lucida leaves by bioassay-guided fractionation and purification. Molucidin was structurally elucidated by (1)H and (13)C NMR including HMQC, HMBC, H-H COSY and NOESY resulting in tetracyclic iridoid skeleton, and its absolute configuration was determined. We have further demonstrated that molucidin presented a strong anti-trypanosomal activity, indicating an IC50 value of 1.27 µM. The cytotoxicity study using human normal and cancer cell lines indicated that molucidin exhibited selectivity index (SI) against two normal fibroblasts greater than 4.73. Furthermore, structure-activity relationship (SAR) study was undertaken with molucidin and oregonin, which is identical to anti-trypanosomal active components of Alnus japonica. Overlapping analysis of the lowest energy conformation of molucidin with oregonin suggested a certain similarities of aromatic rings of both oregonin and molucidin. These results contribute to the future drug design studies for HAT.


Assuntos
Iridoides/química , Iridoides/farmacologia , Morinda/química , Tripanossomicidas/química , Tripanossomicidas/farmacologia , Trypanosoma/efeitos dos fármacos , Animais , Linhagem Celular , Linhagem Celular Tumoral , Humanos , Iridoides/isolamento & purificação , Modelos Moleculares , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Relação Estrutura-Atividade , Tripanossomíase Africana/tratamento farmacológico
8.
BMJ Open ; 3(2)2013.
Artigo em Inglês | MEDLINE | ID: mdl-23430601

RESUMO

OBJECTIVE: To evaluate the content of school textbooks as a tool to prevent tobacco use in developing countries. DESIGN: Content analysis was used to evaluate if the textbooks incorporated the following five core components recommended by the WHO: (1) consequences of tobacco use; (2) social norms; (3) reasons to use tobacco; (4) social influences and (5) resistance and life skills. SETTING: Nine developing countries: Bangladesh, Cambodia, Laos, Nepal, Sri Lanka, Benin, Ghana, Niger and Zambia. TEXTBOOKS ANALYSED: Of 474 textbooks for primary and junior secondary schools in nine developing countries, 41 were selected which contained descriptions about tobacco use prevention. RESULTS: Of the 41 textbooks, the consequences of tobacco use component was covered in 30 textbooks (73.2%) and the social norms component was covered in 19 (46.3%). The other three components were described in less than 20% of the textbooks. CONCLUSIONS: A rather limited number of school textbooks in developing countries contained descriptions of prevention of tobacco use, but they did not fully cover the core components for tobacco use prevention. The chance of tobacco prevention education should be seized by improving the content of school textbooks.

9.
Malar J ; 10: 187, 2011 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-21745377

RESUMO

BACKGROUND: In 2005, Ghana replaced chloroquine with artemisinin-based combination therapy as the first-line treatment for uncomplicated malaria. The aim of this work was to determine for the first time, polymorphisms in the putative pfATPase6 and pftctp, pfmdr1, pfcrt genes in Ghanaian isolates, particularly at a time when there is no report on artemisinin resistance in malaria parasites from Ghana. The sensitivity of parasite isolates to anti-malaria drugs were also evaluated for a possible association with polymorphisms in these genes. METHODS: The prevalence of point mutations in the above Plasmodium falciparum genes were assessed from filter-paper blood blot samples by DNA sequencing. In vitro drug sensitivity test was carried out on some of the blood samples from volunteers visiting hospitals/clinics in southern Ghana using a modified version of the standard WHO Mark III micro-test. RESULTS: All successfully tested parasite isolates were sensitive to artesunate; while 19.4%, 29.0% and 51.6% were resistant to quinine, amodiaquine and chloroquine respectively. The geometric mean of IC50 value for artesunate was 0.73 nM (95% CI, 0.38-1.08), amodiaquine 30.69 nM (95% CI, 14.18-47.20) and chloroquine 58.73 nM (95% CI, 38.08-79.38). Twenty point mutations were observed in pfATPase6 gene, with no L263E and S769N. All mutations found were low in frequency, except D639G which was observed in about half of the isolates but was not associated with artesunate response (p = 0.42). The pftctp gene is highly conserved as no mutation was observed, while CVIET which is chloroquine-resistant genotype at codon 72-76 of the pfcrt gene was identified in about half of the isolates; this was consistent with chloroquine IC50 values (p = 0.001). Mutations were present in pfmdr1 gene but were not associated with artemisinin response (p = 1.00). CONCLUSION: The pfATPase6 gene is highly polymorphic with D639G appearing to be fixed in Ghanaian isolates. These may just be spontaneous mutations as all parasite isolates that were tested displayed satisfactory in vitro response to artesunate. However, there is no improvement in susceptibility of the parasites to chloroquine five years after its proscription.


Assuntos
Antimaláricos/farmacologia , Artemisininas/farmacologia , ATPases Transportadoras de Cálcio/genética , Plasmodium falciparum/efeitos dos fármacos , Plasmodium falciparum/genética , Polimorfismo Genético , Artesunato , Estudos Transversais , Gana , Humanos , Proteínas de Membrana Transportadoras/genética , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Testes de Sensibilidade Parasitária , Mutação Puntual , Proteínas de Protozoários/genética
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