Evaluation of antibody response to Plasmodium falciparum in children according to exposure of Anopheles gambiae s.l or Anopheles funestus vectors

<p>Abstract</p> <p>Background</p> <p>In sub-Saharan areas, malaria transmission was mainly ensured by <it>Anopheles. gambiae </it>s.l. and <it>Anopheles. funestus </it>vectors. The immune response status to <it>Plasmodium falciparum </it>was evaluated in children living in two villages where malaria transmission was ensured by dissimilar species of <it>Anopheles </it>vectors (<it>An. funestus vs An. gambiae </it>s.l.).</p> <p>Methods</p> <p>A multi-disciplinary study was performed in villages located in Northern Senegal. Two villages were selected: Mboula village where transmission is strictly ensured by <it>An. gambiae </it>s.l. and Gankette Balla village which is exposed to several <it>Anopheles </it>species but where <it>An. funestus </it>is the only infected vector found. In each village, a cohort of 150 children aged from one to nine years was followed during one year and IgG response directed to schizont extract was determined by ELISA.</p> <p>Results</p> <p>Similar results of specific IgG responses according to age and <it>P. falciparum </it>infection were observed in both villages. Specific IgG response increased progressively from one-year to 5-year old children and then stayed high in children from five to nine years old. The children with <it>P. falciparum </it>infection had higher specific antibody responses compared to negative infection children, suggesting a strong relationship between production of specific antibodies and malaria transmission, rather than protective immunity. In contrast, higher variation of antibody levels according to malaria transmission periods were found in Mboula compared to Gankette Balla. In Mboula, the peak of malaria transmission was followed by a considerable increase in antibody levels, whereas low and constant anti-malaria IgG response was observed throughout the year in Gankette Balla.</p> <p>Conclusion</p> <p>This study shows that the development of anti-malaria antibody response was profoundly different according to areas where malaria exposure is dependent with different <it>Anopheles </it>species. These results are discussed according to i) the use of immunological tool for the evaluation of malaria transmission and ii) the influence of <it>Anopheles </it>vectors species on the regulation of antibody responses to <it>P. falciparum</it>.</p

Effect of different stages of maturity and postharvest treatments on quality and storability of pineapple

A study was undertaken to evaluate the effects of different maturity stages and postharvest treatments on the storage behavior of Pineapple fruits. Two distinct maturity stages viz., premature (30 days before attaining optimum maturity) and optimum mature fruits were harvested and placed in the laboratory room. On the same day six postharvest treatments viz., control, preserved in unperforated polyethylene bag, tilt, 100 ppm NAA, 200 ppm NAA, and 300 ppm NAA were assigned to that fruits. The two-factor experiment was laid out in a completely randomized design with three replications. There was significant variation between two maturity stages and among different treatments in relation to fruit characteristics. At 18 days of storage, premature fruits contained the maximum shelf-life (19.33 days), total weight loss (16.00%), moisture content (92.66%), total titratable acidity (0.77%), ascorbic acid content (17.49 mg/100g fruit) while the minimum (14.5 days), (14.67%), (90.66%), (0.68%), (9.75 mg/100g fruit) in optimum mature fruits, respectively. On the other hand, optimum mature fruits had higher dry matter content (14.78%), edible portion (67.77%), TSS (16.03%), pulp to peel ratio (2.56), total sugar content (13.5%) while these were minimum (12.57%), (65.16%), (14.43%), (2.37), (10.56%) in pre mature fruits, respectively. The fruits treated with 100 ppm NAA treatment showed the highest shelf life (22.83 days), pulp to peel ratio (2.94), total titratable acidity (0.67%), ascorbic acid content (16.78 mg/100g fruit pulp) and the lowest was in total sugar content (10.96%). Fruits treated with unperforated polythene bag gave the maximum edible portion (71.72%), moisture content (88.3%), and the minimum were in weight loss (3.42%), dry matter content (11.7%), TSS (14.68%). On the other hand, fruits with 5% tilt treatment showed the minimum total titratable acidity (0.58%) and ascorbic acid content (12.28 mg/100 g fruit pulp). Fruits with control represented the highest weight loss (19.135%), dry matter content (13.7%), total sugar content (12.75%) and the lowest were in shelf life (12.66 days), edible portion (60.098%), pulp to peel ratio (1.93). Among the treated and untreated fruits, unperforated polyethylene bag and 100 ppm NAA treatment exhibited better storage performance

Polymer-Based Sustained-Release Dosage Forms for Protein Drugs, Challenges, and Recent Advances

While the concept of using polymer-based sustained-release delivery systems to maintain therapeutic concentration of protein drugs for extended periods of time has been well accepted for decades, there has not been a single product in this category successfully commercialized to date despite clinical and market demands. To achieve successful systems, technical difficulties ranging from protein denaturing during formulation process and the course of prolonged in vivo release, burst release, and incomplete release, to low encapsulation efficiency and formulation complexity have to be simultaneously resolved. Based on this updated understanding, formulation strategies attempting to address these aspects comprehensively were reported in recent years. This review article (with 134 citations) aims to summarize recent studies addressing the issues above, especially those targeting practical industrial solutions. Formulation strategies representative of three areas, microsphere technology using degradable hydrophobic polymers, microspheres made of water soluble polymers, and hydrophilic in vivo gelling systems will be selected and introduced. To better understand the observations and conclusions from different studies for different systems and proteins, physicochemical basis of the technical challenges and the pros and cons of the corresponding formulation methods will be discussed