In silico characterisation of putative Plasmodium falciparum vaccine candidates in African malaria populations.

Genetic diversity of surface exposed and stage specific Plasmodium falciparum immunogenic proteins pose a major roadblock to developing an effective malaria vaccine with broad and long-lasting immunity. We conducted a prospective genetic analysis of candidate antigens (msp1, ama1, rh5, eba175, glurp, celtos, csp, lsa3, Pfsea, trap, conserved chrom3, hyp9, hyp10, phistb, surfin8.2, and surfin14.1) for malaria vaccine development on 2375 P. falciparum sequences from 16 African countries. We described signatures of balancing selection inferred from positive values of Tajima's D for all antigens across all populations except for glurp. This could be as a result of immune selection on these antigens as positive Tajima's D values mapped to regions with putative immune epitopes. A less diverse phistb antigen was characterised with a transmembrane domain, glycophosphatidyl anchors between the N and C- terminals, and surface epitopes that could be targets of immune recognition. This study demonstrates the value of population genetic and immunoinformatic analysis for identifying and characterising new putative vaccine candidates towards improving strain transcending immunity, and vaccine efficacy across all endemic populations

Molecular Epidemiology of Endemic Human T-Lymphotropic Virus Type 1 in a Rural Community in Guinea-Bissau

Human T-Lymphotropic Virus type 1 (HTLV-1) affects millions of people worldwide. It is very similar to Simian T-Lymphotropic Virus, a virus that circulates in monkeys. HTLV-1 causes a lethal form of leukemia (Adult T-cell Leukemia) and a debilitating neurological syndrome (HTLV-associated myelopathy/tropical spastic paraparesis) in approximately 5% of infected people. Based on sequence variation, HTLV-1 can be divided into 7 subtypes (1a–1g) with the Cosmopolitan subtype 1a further subdivided into subgroups (A–E). We examined HTLV-1 diversity in a rural area in Guinea-Bissau, a country in West Africa with a high HTLV-1 prevalence (5%). We found that most viruses belong to the Cosmopolitan subtype 1a, subgroup D, but 2 viruses belonged to subtype 1g. This subtype had thus far only been found in monkey hunters in Cameroon, who were probably recently infected by monkeys. Our findings indicate that this subtype has spread beyond Central Africa. An important, unresolved question is whether persons with this subtype were infected by monkeys or through human-to-human transmission

Clinical and Virological Study of Dengue Cases and the Members of Their Households: The Multinational DENFRAME Project

Dengue is the most important mosquito-borne viral disease in humans. This disease is now endemic in more than 100 countries and threatens more than 2.5 billion people living in tropical countries. It currently affects about 50 to 100 million people each year. It causes a wide range of symptoms, from an inapparent to mild dengue fever, to severe forms, including dengue hemorrhagic fever. Currently no specific vaccine or antiviral drugs are available. We carried out a prospective clinical study in South-East Asia and Latin America, of virologically confirmed dengue-infected patients attending the hospital, and members of their households. Among 215 febrile dengue subjects, 177 agreed to household investigation. Based on our data, we estimated the proportion of dengue-infected household members to be about 45%. At the time of the home visit, almost three quarters of (29/39) presented an inapparent dengue infection. The proportion of inapparent dengue infection was higher in South-East Asia than in Latin America. These findings confirm the complexity of dengue disease in humans and the need to strengthen multidisciplinary research efforts to improve our understanding of virus transmission and host responses to dengue virus in various human populations

Guidelines for the use and interpretation of assays for monitoring autophagy (4th edition)1.

In 2008, we published the first set of guidelines for standardizing research in autophagy. Since then, this topic has received increasing attention, and many scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Thus, it is important to formulate on a regular basis updated guidelines for monitoring autophagy in different organisms. Despite numerous reviews, there continues to be confusion regarding acceptable methods to evaluate autophagy, especially in multicellular eukaryotes. Here, we present a set of guidelines for investigators to select and interpret methods to examine autophagy and related processes, and for reviewers to provide realistic and reasonable critiques of reports that are focused on these processes. These guidelines are not meant to be a dogmatic set of rules, because the appropriateness of any assay largely depends on the question being asked and the system being used. Moreover, no individual assay is perfect for every situation, calling for the use of multiple techniques to properly monitor autophagy in each experimental setting. Finally, several core components of the autophagy machinery have been implicated in distinct autophagic processes (canonical and noncanonical autophagy), implying that genetic approaches to block autophagy should rely on targeting two or more autophagy-related genes that ideally participate in distinct steps of the pathway. Along similar lines, because multiple proteins involved in autophagy also regulate other cellular pathways including apoptosis, not all of them can be used as a specific marker for bona fide autophagic responses. Here, we critically discuss current methods of assessing autophagy and the information they can, or cannot, provide. Our ultimate goal is to encourage intellectual and technical innovation in the field

Bis(triphenyltin) oxalate

The centrosymmetric structure of bis(triphenyltin) oxalate contains essentially four-coordinated tin and monodentate carboxylate moieties despite a Mossbauer quadrupole splitting of 2.8 mm s(-1) and a Sn-119 NMR chemical shift of -503 ppm. Copyright (C) 2003 John Wiley Sons, Ltd

Synthesis, spectroscopic studies and crystal structure of (Et4N)(SnMe3)(7)(HASO(4))(4) center dot 2H(2)O

On allowing tetraethylammonium dihydrogen arsenate dihydrate to react with trimethyltin chloride, the title compound has been obtained and characterized by infrared, Mossbauer and NMR techniques. Its crystal structure has been determined and consists of layers containing both corner sharing AsO4H tetrahedra and trans-O2SnC3 entities. It contains large cavities in which tetraethylamonium cations are located. (C) 2004 Elsevier B.V. All rights reserved

Evaluation Du Test De Diagnostic Rapide NOVA Utilisé Pour Rechercher L’antigène HBS de l’Hépatite B Chez Les Donneurs De Sang Au Centre Hospitalier National Mathlaboul Fawzaini De Touba

RésuméDans les pays en développement, les tests rapides immuno-chromatographiques sont couramment utilisés pour le dépistage du virus de l’hépatite B (VHB) au niveau des banques de sang. L’usage de ces tests nécessite une validation préalable. L’objectif de l’étude était d’évaluer les performances du test NOVA utilisé pour le dépistage de l’antigène HBs chez des donneurs de sang au Centre Hospitalier National Mathlaboul Fawzaini de Touba.En janvier 2019, des échantillons de sang provenant de donneurs avaient fait l’objet de dépistage du VHB avec le test rapide NOVA. Les résultats obtenus ont été comparés avec ceux de l’automate Cobas e-411 dont le principe consiste en un dosage par chimiluminescence. La sensibilité du test, la spécificité ainsi que les valeurs prédictives positive et négative ont été calculées pour vérifier la fiabilité du kit. Au total 111 échantillons ont été collectés. Les résultats des tests positifs obtenus avec le kit NOVA et le Cobas e-411 étaient de 17 et 19 respectivement. Par rapport à l’automate Cobas, les résultats ont donné une sensibilité et une spécificité du test NOVA de 89,47 % et 100 % respectivement ; les VPP et les VPN étaient respectivement de 100 % et 97,87 %.Les résultats obtenus montrent que le test NOVA a une bonne spécificité. Cependant la sensibilité est relativement faible pour un usage dans les banques de sang. La méthode chimiluminescente étant plus sensible et plus spécifique devrait être privilégiée dans le dépistage de masse pour plus de fiabilité et de qualité.Mots clés : Test rapide, Hépatite B, Donneurs de sangAbstractIn developing countries, rapid immuno-chromatographic tests are commonly used to screen blood banks for hepatitis B virus (HBV). The use of these tests requires prior validation. The objective of the study was to evaluate the performance of the NOVA test used to screen blood donors for HBs antigen at the National Hospital Center Mathlaboul Fawzaini in Touba.In January 2019, blood samples from donors were screened for HBV using the NOVA rapid test. The results obtained were compared with those of the Cobas e-411 automated chemiluminescent assay. Test sensitivity, specificity, and positive and negative predictive values were calculated to verify the fiability of the kit. A total of 111 samples were collected. The positive test results obtained with the NOVA kit and the Cobas e-411 were 17 and 19 respectively. Compared to the Cobas system, the results gave a NOVA test sensitivity and specificity of 89.47% and 100% respectively; PPV and NPV were 100% and 97.87% respectively.The results obtained show that the NOVA test has good specificity. However, the sensitivity is relatively low for use in blood banks. The chemiluminescent method being more sensitive and more specific should be preferred in mass screening for more reliability and quality.Key words: Rapid test, Hepatitis B, Blood donor

Acute and recurrent symptomatic urinary tract infections in women

It has become clear in recent years that the human intestinal microbiota plays an important role in maintaining health and thus is an attractive target for clinical interventions. Scientists and clinicians have become increasingly interested in assessing the ability of probiotics and prebiotics to enhance the nutritional status of malnourished children, pregnant women, the elderly, and individuals with non-communicable disease-associated malnutrition. A workshop was held by the International Scientific Association for Probiotics and Prebiotics (ISAPP), drawing on the knowledge of experts from industry, medicine, and academia, with the objective to assess the status of our understanding of the link between the microbiome and under-nutrition, specifically in relation to probiotic and prebiotic treatments for under-nourished individuals. These discussions led to four recommendations: (1) The categories of malnourished individuals need to be differentiated. To improve treatment outcomes, subjects should first be categorized based on the cause of malnutrition, additional health-concerns, differences in the gut microbiota, and sociological considerations. (2) Define a baseline healthy gut microbiota for each category. Altered nutrient requirement (for example, in pregnancy and old age) and individual variation may change what constitutes a healthy gut microbiota for the individual. (3) Perform studies using model systems to test the effectiveness of potential probiotics and prebiotics against these specific categories. These should illustrate how certain microbiota profiles can be altered, as members of different categories may respond differently to the same treatment. (4) Perform robust well-designed human studies with probiotics and/or prebiotics, with appropriate, defined primary outcomes and sample size. These are critical to show efficacy and understand responder and non-responder outcomes. It is hoped that these recommendations will lead to new approaches that combat malnutrition. © 2014 Landes Bioscience