Phytochemical and comparative antidiabetic studies of leaf extracts of Viscum album from different plant hosts

Phytochemical screening and evaluation of antidiabetic activity of leaf extracts of Viscum album from four different plant hosts were carried out using standard procedures. The results of the phytochemical screening revealed that the different leaf extracts vary in their phytochemical constituents depending on the plant host. Moreso, all the leaf extracts of Viscum album demonstrated significant (p<0.001) lowering of blood glucose level (BGL) in alloxan-induced diabetic rats. The leaf extract of V. album from Dennettia tripetala exhibited the highest antidiabetic activity than the other extracts followed by Citrus sinensis and Pisium guajava and their activities were more pronounced than that of standard drug, glibenclamide during acute study. On prolonged treatment, Viscum album leaf extracts from C. sinensis (VAC ) and P. guajava (VAP) had comparably higher antidiabetic effects than the other extracts and glibenclamide. These were followed by that from Dacroydes edulis (VAD) while Dennettia tripetala (VADT) had the lowest antidiabetic effect. Although V. album possesses antidiabetic property, its antidiabetic efficacy depends on its phytochemical constituents which in turn depends on the plant host.Keywords: Mistletoe, Hyperglycemia, Alloxan, Glibenclamid

Geographical information system and predictive risk maps of urinary schistosomiasis in Ogun State, Nigeria

<p>Abstract</p> <p>Background</p> <p>The control of urinary schistosomiasis in Ogun State, Nigeria remains inert due to lack of reliable data on the geographical distribution of the disease and the population at risk. To help in developing a control programme, delineating areas of risk, geographical information system and remotely sensed environmental images were used to developed predictive risk maps of the probability of occurrence of the disease and quantify the risk for infection in Ogun State, Nigeria.</p> <p>Methods</p> <p>Infection data used were derived from carefully validated morbidity questionnaires among primary school children in 2001–2002, in which school children were asked among other questions if they have experienced "blood in urine" or urinary schistosomiasis. The infection data from 1,092 schools together with remotely sensed environmental data such as rainfall, vegetation, temperature, soil-types, altitude and land cover were analysis using binary logistic regression models to identify environmental features that influence the spatial distribution of the disease. The final regression equations were then used in Arc View 3.2a GIS software to generate predictive risk maps of the distribution of the disease and population at risk in the state.</p> <p>Results</p> <p>Logistic regression analysis shows that the only significant environmental variable in predicting the presence and absence of urinary schistosomiasis in any area of the State was Land Surface Temperature (LST) (B = 0.308, p = 0.013). While LST (B = -0.478, p = 0.035), rainfall (B = -0.006, p = 0.0005), ferric luvisols (B = 0.539, p = 0.274), dystric nitosols (B = 0.133, p = 0.769) and pellic vertisols (B = 1.386, p = 0.008) soils types were the final variables in the model for predicting the probability of an area having an infection prevalence equivalent to or more than 50%. The two predictive risk maps suggest that urinary schistosomiasis is widely distributed and occurring in all the Local Government Areas (LGAs) in State. The high-risk areas (≥ 50% prevalence) however, are confined to scatter foci in the north western part of the State. The model also estimated that 98.99% of schools aged children (5–14 years) are living in areas suitable for urinary schistosomiasis transmission and are at risk of infection.</p> <p>Conclusion</p> <p>The risk maps developed will hopefully be useful to the state health officials, by providing them with detailed distribution of urinary schistosomiasis, help to delineate areas for intervention, assesses population at risk thereby helping in optimizing scarce resources.</p

Urinary schistosomiasis among preschool-aged children in Sahelian rural communities in Mali

<p>Abstract</p> <p>Background</p> <p>Mass chemotherapy with praziquantel is the main control strategy for schistosomiasis in Mali. However, in the national control programme for schistosomiasis and soil-transmitted helminthiasis, infants and preschool-aged children are overlooked in preventive chemotherapy campaigns. We therefore determined the prevalence and intensity of urinary schistosomiasis in children between the ages 1-4 years in three villages across Diema health district, a rural community with endemic schistosomiasis in Mali. For <it>Schistosoma haematobium </it>diagnosis, a single urine sample of 10 ml obtained from each child was subjected to the standard urine filtration method.</p> <p>Results</p> <p>Of the 338 children examined 173 (51.2%) were infected. Both prevalence and intensity of infection varied significantly between communities (p < 0.01). There was no significant difference (p = 0.94) in infection rates between boys (51.2%) and girls (50.3%). Likewise, prevalence did not significantly increase with age (p = 0.86). The overall geometric mean of Williams (GMw) was 18.41 eggs/10 ml urine, with no significant association (p = 0.91) between boys (17.48 eggs/10 ml urine) and girls (19.69 eggs/10 ml urine). However, the GMw significantly increased with age (p = 0.04). Infection of preschool children would occur through early exposure to infected water bodies through both passive and active process.</p> <p>Conclusion</p> <p>Our study showed that preschool children living closely to lakes across in Mali are at high risk to be infected by schistosomiasis and contributed largely to the transmission; therefore schistosomiasis control interventions should also target infants in addition to school children and adults in endemic areas.</p

Putting the treatment of paediatric schistosomiasis into context

Abstract Despite increased international efforts to control schistosomiasis using preventive chemotherapy, several challenges still exist in reaching the target populations. Until recently, preschool-aged children had been excluded from the recommended target population for mass drug administration, i.e. primary school children aged 6–15 years. Our studies and those of others provided the evidence base for the need to treat preschool-aged children that led to recommendations by the World Health Organization to include preschool-aged children in treatment programmes in 2010. The major challenge now lies in the unavailability of a child-size formulation of the appropriate anthelmintic drug, praziquantel. The currently available formulation of praziquantel presents several problems. First, it is a large tablet, making it difficult for young children and infants to swallow it and thus requires its breaking/crushing to allow for safe uptake. Second, it is bitter so it is often mixed with a sweetener to make it palatable for young children. Third, the current formulation of 600 mg does not allow for flexible dose adjustments for this age group. Thus, there is a need to formulate a child-appropriate praziquantel tablet. This paper discusses the target product profile for paediatric praziquantel, as well as knowledge gaps pertinent to the successful control of schistosome infection and disease in preschool-aged children

Neglected Tropical Diseases in Sub-Saharan Africa: Review of Their Prevalence, Distribution, and Disease Burden

The neglected tropical diseases (NTDs) are the most common conditions affecting the poorest 500 million people living in sub-Saharan Africa (SSA), and together produce a burden of disease that may be equivalent to up to one-half of SSA's malaria disease burden and more than double that caused by tuberculosis. Approximately 85% of the NTD disease burden results from helminth infections. Hookworm infection occurs in almost half of SSA's poorest people, including 40–50 million school-aged children and 7 million pregnant women in whom it is a leading cause of anemia. Schistosomiasis is the second most prevalent NTD after hookworm (192 million cases), accounting for 93% of the world's number of cases and possibly associated with increased horizontal transmission of HIV/AIDS. Lymphatic filariasis (46–51 million cases) and onchocerciasis (37 million cases) are also widespread in SSA, each disease representing a significant cause of disability and reduction in the region's agricultural productivity. There is a dearth of information on Africa's non-helminth NTDs. The protozoan infections, human African trypanosomiasis and visceral leishmaniasis, affect almost 100,000 people, primarily in areas of conflict in SSA where they cause high mortality, and where trachoma is the most prevalent bacterial NTD (30 million cases). However, there are little or no data on some very important protozoan infections, e.g., amebiasis and toxoplasmosis; bacterial infections, e.g., typhoid fever and non-typhoidal salmonellosis, the tick-borne bacterial zoonoses, and non-tuberculosis mycobaterial infections; and arboviral infections. Thus, the overall burden of Africa's NTDs may be severely underestimated. A full assessment is an important step for disease control priorities, particularly in Nigeria and the Democratic Republic of Congo, where the greatest number of NTDs may occur