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In Burkina Faso untreated Solid Urban Wastes (SUW) are commonly used as agricultural fertilizers. This study aims to highlight the impacts of this current practice on soil agronomic properties and crop production. Sampling was carried out in Ouagadougou sub-urban agricultural fields. Agronomic tests, physical and chemical analyses were carried out following lab common procedures. The fertility of the soils was assessed through a greenhouse experiment with maize as test crop. The results showed that amendment significantly increased the pH, total C, N, P and available P contents as p-values were

Legume and Cereal Cropping in Zaï System with Different Organo-mineral Amendments - Productivity and Impact on Biological Properties of Degraded Bare Alfisol in North Sudanian Zone of Burkina Faso. Zaï is an agricultural practice that allows the cultivation of abandoned degraded soils. An experiment was conducted from 2006 to 2012 in Burkina Faso to assess the impact of this practice on the production of sorghum and cowpea, as well as on the biological properties of soils. The experiment was set up according to a factorial experimental design in Fischer blocks. The crops were grown in the trial , received different types of organic (manure, compost) and mineral (rock phosphate) input. The results showed that the intake of simple manure and compost significantly increased the yield of the two crops. The addition of phosphate (2 t.ha-1) to compost (3 t.ha-1) and to manure (3 t.ha-1) increased the yields of cowpea and sorghum respectively by 70 to 80% and 88 to 160% compared to sole compost and manure applications. The biological activity of the soil was not influenced by the type of crop but rather by organo-mineral intakes. The combination of rock phosphate to manure had a particularly positive effect on soil biological activity. The natural phosphate intake associated with organic matter therefore appears essential to maintain crop production and soil properties.

Objectives of this prospective study conducted from November 2011 to July 2013 in Bobo-Dioulasso were to evaluate seroprevalence of toxoplasma infection and to screen maternal and congenital toxoplasmosis during pergravidique monitoring. Material and methods -Techniques of High Sensitivity Direct Agglutination (HSDA) and ELFA (enzyme linked fluorescent assay) respectively were used for the detection of IgG and IgM toxoplasma. The IgG avidity assay was used for the dating of seroconverswn. Screening and monitoring for fetal lesions were echographic. In case of seroconversion, a prenatal treatment with pyrimethamine and sulfamide was introduced. Systematically and regularly immunoassay surveillance of newborn from cases of recent pergravidique toxoplasmosis was performed until complete and final negativity of serology. Results- In total 301 pregnant were included. The overall seroprevalence was 31.9%. Three cases of seroconversion (0.9%) including two cases at the 22nd and one at the 41th week of amenorrhea were noted. Series of obstetrical echography have detected no case of fetal Toxoplasma gondii infection and no congenital toxoplasmosis was detected. Conclusion-This study underlines the importance of implementation of a legal disposition for screening and routine monitoring of toxoplasmosis during pregnancy. This is due to the low rate (31.9%) of toxoplasma immunity among gestante in Burkina Faso that may lead to pergravidique acute toxoplasmosis or congenital toxoplasmosis whose outcome is often fatal. [ABSTRACT FROM AUTHOR]

With the ongoing development of conjugate vaccines battling infectious diseases, there is a need for novel carriers. Although tetanus toxoid and CRM197 belong to the traditional carrier proteins, outer-membrane vesicles (OMVs) are an excellent alternative: in addition to their size, OMVs have self-adjuvanting properties due to the presence of genetically detoxified lipopolysaccharide (LPS) and are therefore ideal as a vaccine component or antigen carrier. An essential aspect of their development for vaccine products is characterization of OMVs with respect to size and purity. We report on the development of a field-flow fractionation multiangle light-scattering (FFF-MALS) method for such characterization. Here, we introduced NIST-traceable particle-size standards and BSA as a model protein to verify the precision of the size and purity analysis of the OMVs. We executed a validation program according to the principles provided in the ICH Guidelines Q2 (R1) to assess the quality attributes of the results obtained by FFF-MALS analysis. All validation characteristics showed excellent results with coefficients of variation between 0.4 and 7.32%. Estimation of limits of detection for hydrodynamic radius and particle concentration revealed that as little as 1 μg OMV still yielded accurate results. With the validated method, we further characterized a full downstream purification process of our proprietary OMV. This was followed by the evaluation of other purified OMVs from different bacterial origin. Finally, functionalizing OMVs with N -γ-(maleimidobutyryl)oxysuccinimide-ester (GMBS), generating ready-to-conjugate OMVs, did not affect the structural integrity of the OMVs and as such, they could be evaluated with the validated FFF-MALS method.

The potential of lipid nanoparticles (LNPs) as nucleic acid delivery vehicles has been demonstrated in recent years, culminating in the emergency use approval of LNP-based mRNA SARS-CoV-2 vaccines in late 2020. The determination of RNA content relative to LNP size can be important to the understanding of efficacy and adverse effects. This work presents the first description of a facile and rapid analytical method for online, size-dependent RNA payload distribution measurement using data from multi-angle light scattering, ultraviolet and refractive index detectors following separation of the LNPs by size-exclusion chromatography. The analysis was validated by size-based fractionation of the LNPs with subsequent offline analysis of the fractions. Four LNPs formulated with different PEG-lipids and different lipid compositions were tested. Good agreement was observed between the online and offline size-based RNA distributions among all four LNPs, demonstrating the utility of the online method for LNP-encapsulated RNA in general, and suggesting a means for simplified biophysical quantitation of a dosing-related critical quality attribute., (Copyright © 2021 Merck Sharp & Dohme Corp., The Author(s). Published by Elsevier B.V. All rights reserved.)

Analytical size-exclusion chromatography (SEC), commonly used for the determination of the molecular weight of proteins and protein-protein complexes in solution, is a relative technique that relies on the elution volume of the analyte to estimate molecular weight. When the protein is not globular or undergoes non-ideal column interactions, the calibration curve based on protein standards is invalid, and the molecular weight determined from elution volume is incorrect. Multi-angle light scattering (MALS) is an absolute technique that determines the molecular weight of an analyte in solution from basic physical equations. The combination of SEC for separation with MALS for analysis constitutes a versatile, reliable means for characterizing solutions of one or more protein species including monomers, native oligomers or aggregates, and heterocomplexes. Since the measurement is performed at each elution volume, SEC-MALS can determine if an eluting peak is homogeneous or heterogeneous and distinguish between a fixed molecular weight distribution versus dynamic equilibrium. Analysis of modified proteins such as glycoproteins or lipoproteins, or conjugates such as detergent-solubilized membrane proteins, is also possible. Hence, SEC-MALS is a critical tool for the protein chemist who must confirm the biophysical properties and solution behavior of molecules produced for biological or biotechnological research. This protocol for SEC-MALS analyzes the molecular weight and size of pure protein monomers and aggregates. The data acquired serve as a foundation for further SEC-MALS analyses including those of complexes, glycoproteins and surfactant-bound membrane proteins.

Ion-exchange chromatography with multi-angle light scattering (IEX-MALS) is a powerful method for protein separation and characterization. The combination of the high-specificity separation technique IEX with the accurate molar mass analysis achieved by MALS allows the characterization of heterogeneous protein samples, including mixtures of oligomeric forms or protein populations, even with very similar molar masses. Therefore, IEX-MALS provides an additional level of protein characterization and is complementary to the standard size-exclusion chromatography with multi-angle light scattering (SEC-MALS) technique. Here we describe a protocol for a basic IEX-MALS experiment and demonstrate this method on bovine serum albumin (BSA). IEX separates BSA to its oligomeric forms allowing a molar mass analysis by MALS of each individual form. Optimization of an IEX-MALS experiment is also presented and demonstrated on BSA, achieving excellent separation between BSA monomers and larger oligomers. IEX-MALS is a valuable technique for protein quality assessment since it provides both fine separation and molar mass determination of multiple protein species that exist in a sample.

We present a review of high-throughput techniques for the characterization and quality control of proteins in the course of purification, evaluation, and formulation, based on static and dynamic light scattering. Multi-angle static light scattering (MALS) in combination with rapid, low-volume UHPLC size exclusion chromatography is effective in characterizing key biophysical properties, while dynamic light scattering (DLS) in high-throughput microwell-plate format provides large quantities of data in a short time to screen many conditions, excipients, cell lines, or candidate biotherapeutics.

Analysis of weakly self-associating macromolecules at concentrations beyond a few g/L is challenging on account of the confounding effect of thermodynamic nonideality on the association signal. When the reversible association comprises only 1 or 2 oligomeric species in equilibrium with the monomer, the nonideality may be accounted for in a relatively rigorous manner, but if more association states are involved, the analysis becomes quite complex. We show that under reasonable assumptions, the nonideality in a composition-gradient static light scattering measurement may be accounted for in a simple fashion. The correction is applied to determining the stoichiometry and binding affinity of a protein previously characterized via sedimentation equilibrium and dynamic light scattering. The results of the new analysis are remarkably self-consistent and in line with the expectations for the form of self-association predicted previously from analysis of the surface residuals, establishing composition-gradient multi-angle static light scattering with nonideality corrections as a critical technology for characterizing associative interactions in concentrated solutions., (Copyright © 2016 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.)

Background: Outbreaks of methanol poisoning occur frequently on a global basis, affecting poor and vulnerable populations. Knowledge regarding methanol is limited, likely many cases and even outbreaks go unnoticed, with patients dying unnecessarily. We describe findings from the first three large outbreaks of methanol poisoning where Médecins Sans Frontières (MSF) responded, and evaluate the benefits of a possible future collaboration between local health authorities, a Non-Governmental Organisation and international expertise., Methods: Retrospective study of three major methanol outbreaks in Libya (2013) and Kenya (May and July 2014). Data were collected from MSF field personnel, local health personnel, hospital files, and media reports., Findings: In Tripoli, Libya, over 1,000 patients were poisoned with a reported case fatality rate of 10% (101/1,066). In Kenya, two outbreaks resulted in approximately 341 and 126 patients, with case fatality rates of 29% (100/341) and 21% (26/126), respectively. MSF launched an emergency team with international experts, medications and equipment, however, the outbreaks were resolving by the time of arrival., Interpretation: Recognition of an outbreak of methanol poisoning and diagnosis seem to be the most challenging tasks, with significant delay from time of first presentations to public health warnings being issued. In spite of the rapid response from an emergency team, the outbreaks were nearly concluded by the time of arrival. A major impact on the outcome was not seen, but large educational trainings were conducted to increase awareness and knowledge about methanol poisoning. Based on this training, MSF was able to send a local emergency team during the second outbreak, supporting that such an approach could improve outcomes. Basic training, simplified treatment protocols, point-of-care diagnostic tools, and early support when needed, are likely the most important components to impact the consequences of methanol poisoning outbreaks in these challenging contexts.

Background: In sub-Saharan Africa there is an increasing need to leverage available health care workers to provide care for non-communicable diseases (NCDs). This study was conducted to evaluate adherence to Médecins Sans Frontières clinical protocols when the care of five stable NCDs (hypertension, diabetes mellitus type 2, epilepsy, asthma, and sickle cell) was shifted from clinical officers to nurses., Methods: Descriptive, retrospective review of routinely collected clinic data from two integrated primary health care facilities within an urban informal settlement, Kibera, Nairobi, Kenya (May to August 2014)., Results: There were 3,554 consultations (2025 patients); 733 (21%) were by nurses out of which 725 met the inclusion criteria among 616 patients. Hypertension (64%, 397/616) was the most frequent NCD followed by asthma (17%, 106/616) and diabetes mellitus (15%, 95/616). Adherence to screening questions ranged from 65% to 86%, with an average of 69%. Weight and blood pressure measurements were completed in 89% and 96% of those required. Laboratory results were reviewed in 91% of indicated visits. Laboratory testing per NCD protocols was higher in those with hypertension (88%) than diabetes mellitus (67%) upon review. Only 17 (2%) consultations were referred back to clinical officers., Conclusion: Nurses are able to adhere to protocols for managing stable NCD patients based on clear and standardized protocols and guidelines, thus paving the way towards task shifting of NCD care to nurses to help relieve the significant healthcare gap in developing countries.

The objectives of this prospective study, conducted from November 2011 to July 2013, in Bobo-Dioulasso were to evaluate seroprevalence of toxoplasma infection and to screen for maternal and congenital toxoplasmosis during pergravidic monitoring., Material and Methods: Techniques of High Sensitivity Direct Agglutination (HSDA) and Enzyme Linked Fluorescent Assay (ELFA) were used for the detection of IgG and IgM toxoplasma respectively. The IgG avidity assay was used for the dating of seroconversion. Screening and monitoring for fetal lesions were echographic. In case of seroconversion, a prenatal treatment with pyrimethamine and sulphonamide was introduced. Systematically and regularly immunoassay surveillance of newborn from cases of recent pergravidic toxoplasmosis was performed until complete and final negativity of serology., Results: In total 301 pregnant women were included. The overall seroprevalence was 31.9%. Three cases of seroconversion (0.9%) including two cases at the 22 nd and one at the 41 th week of amenorrhea were noted. Series of obstetrical echography have detected no case of fetal Toxoplasma gondii infection and no congenital toxoplasmosis was detected., Conclusion: This study underlines the importance of implementation of a legal disposition for screening and routine monitoring of toxoplasmosis during pregnancy. This is due to the low rate (31.9%) of toxoplasma immunity among gestante in Burkina Faso that may lead to pergravidic acute toxoplasmosis or congenital toxoplasmosis whose outcome is often fatal., (Le comitée de rédaction se réserve le droit de revoyer aux auteurs avant toute soumission à l'avis des lecteurs les manuscrits qui ne seraient pas conformes à ces modalités de présentation. En outre il leur conseille de sonserver un examplaire du manuscrit, des figures et des tableaux.)

Objective: to describe the feasibility and results of at-home follow-up of mothers and newborns discharged early from the maternity ward after normal childbirth., Method: This prospective descriptive study took place during a one month period (April 1-30, 2011) in five maternity units in Bobo-Dioulasso, the second largest city in Burkina Faso. Mothers with normal vaginal deliveries and no complications at the sixth hour postpartum were included in the study with their newborns after informed oral consent. The discharge took place between 12 and 48 hours after delivery. The follow-up took place by telephone, home visits, and emergency hospital visits in cases of complications. A postnatal hospital visit was systematically planned for day 7., Results: The study included 630 mothers and their babies. There were 1567 phone calls made: 27 women could not be reached by telephone after discharge, and 140 home visits took place, either at the mother's request or because of the failure to reach her by telephone. Complications were observed in 55 mothers and 135 babies., Conclusion: Postnatal follow-up at home is required for mothers and their newborns discharged early from the maternity ward after normal childbirth in view of the possibility of complications. This ensures continuity of care to improve survival of mothers and babies. As cell phones become more and more available, they may play an important role as a tool for such follow up.

While light scattering has long been applied to the analysis of biomolecular interactions, recent advances have extended the practical use of light scattering techniques to cover a rather broad range of phenomena. In this paper I review essential light scattering theory as applied to specific interactions under thermodynamically ideal conditions and present examples showing how light scattering elucidates the dynamic equilibrium and kinetic behavior of proteins and other biomacromolecules.

Malaria is still a public health problem in many sub-Saharan countries. This study was undertaken to understand and analyze the relationship between local perceptions of malaria and practices for prevention and management in the department of Gaoua in Burkina Faso. The goal was to improve the effectiveness of prevention and management of malaria in the target population, i.e., children under the age of five. Individual interviews and focus groups using a semi-structured guide were carried out with mothers, traditional healthcare providers and elderly persons in four villages of the department of Gaoua. Findings showed that practices used for treatment and prevention were directly related to perceptions about malaria. Due to poverty, inadequate health service delivery and ignorance, people do not always seek medical attention and express doubts about the efficacy of modern care. Endogenous practices for malaria prevention are directly related to causes described by the population. Modern preventive techniques are not used by the population. For instance nets are misused to protect corpses from flies or for shelter during funerals.