Prédiction des propriétés d'équilibre dans les milieux biologiques et alimentaires par le modèle COSMO-RS

Food and biological systems are generally multicomponent mixtures (including water, organic solvents, dissolved solids, dissolved gases, ionic species, macromolecules). The prediction of the equilibrium properties of such environments requires the use of a fully predictive thermodynamic model. This model must be able to ensure the consistency between experimental data and to ensure the robustness of the simultaneous representation of physical equilibria (liquid-vapour, solubility, etc.) and chemical equilibria (dissociation, redox, complexation, etc.). The chemical potential is an essential property for modelling such equilibria. Its determination depends on two variables: the Gibbs free energy of formation in a chosen reference state, and the prediction of the activity coefficient which also depends on the chosen reference state. The COSMO-RS model is an excellent model for predicting activity coefficients that is widely used in chemical engineering where the studied molecules are generally neutral. This PhD study enabled to extend the performance of the COSMO-RS model toward the treatment of food and biological systems where there are systematically electrolytes in solution (in addition to neutral molecules). A new tool based on the recent advances of quantum mechanics has been developed in order to predict gas phase formation properties. By combining concepts of thermodynamics, quantum physics, electrostatics and statistical physics, it has been demonstrated that it is possible to use the COSMO-RS model to ensure the transition between the gas phase and the condensed phase. In this context, this work demonstrates that it is possible to treat simultaneously physical and chemical equilibria and thus to predict physico-chemical properties (aW, pH, Eh) in food and biological systems using the COSMO-RS model.Les milieux biologiques et alimentaires sont généralement des mélanges contenant un nombre élevé de constituants (eau, solvants organiques, solides dissous, gaz dissous, espèces ioniques, macromolécules). La prédiction des propriétés d’équilibre de tels milieux requiert l’utilisation d’un modèle thermodynamique entièrement prédictif. Ce modèle doit également permettre d’assurer la cohérence entre des données expérimentales et garantir la robustesse de la représentation simultanée des équilibres physiques (liquide-vapeur, solubilité, etc.) et chimiques (dissociation, oxydo-réduction, complexation, etc.). Le potentiel chimique est une donnée indispensable pour modéliser ces équilibres. Sa connaissance dépend de la prédiction de deux variables : l’enthalpie libre de formation dans un état de référence choisi, et le coefficient d’activité qui dépend aussi de l’état de référence choisi. Le modèle COSMO-RS est un excellent modèle de prédiction des coefficients d’activité très largement utilisé dans le domaine du génie chimique où on s’intéresse essentiellement à des molécules neutres. Ce travail de thèse a permis d’étendre les performances du modèle COSMO-RS au traitement des milieux biologiques et alimentaires dans lesquels on trouve systématiquement des électrolytes en solution (en plus des molécules neutres). Un nouvel outil utilisant les récentes avancées de la mécanique quantique a été développé pour prédire les propriétés de formation à l’état gaz. En combinant des concepts de la thermodynamique, de la mécanique quantique, de l’électrostatique, et de la physique statistique, il a été démontré qu’il est possible d’utiliser le modèle COSMO-RS pour faire la transition entre l’état gaz et la phase condensée. Partant de là, ce travail démontre qu’il est maintenant possible de traiter simultanément les équilibres physiques et chimiques et donc de prédire les propriétés physico-chimiques (aW, pH, Eh) dans les milieux biologiques et alimentaires par le modèle COSMO-RS

El impacto del turismo en la Lengua de Barbarie (delta del río Senegal)

Ndiébène Gandiol, a municipality located in the Senegal river delta, has as the main tourism attraction the Langue de Barbarie National Park. This area is currently an incipient ecotourism destination, but the impact of the tourism activity is already clear, both over the environment and over the local society and economy. The article analyses the impact of the tourism over this small and fragile area, an area that has low levels of development and infrastructures and facilities provision. The analysis has been done from interviews to local stakeholders, as well as perception surveys amongst the local population. Lastly, some actions are suggested in order to favor a sustainable management of tourism in the area.Ndiébène Gandiol, un municipio situado en el delta del río Senegal, tiene como principal atractivo turístico el Parque Nacional de la Lengua de Barbarie. Este espacio es actualmente un destino ecoturístico incipiente, pero el impacto de la actividad turística ya es evidente, tanto sobre el medio ambiente como sobre la sociedad y la economía local. El artículo analiza el impacto del turismo sobre este pequeño y frágil territorio, con un bajo nivel de desarrollo y un elevado déficit de equipamientos e infraestructuras. El análisis se realiza a partir de entrevistas a los agentes del territorio, así como de encuestas de percepción entre la población local. Finalmente, se proponen acciones para favorecer una gestión sostenible del turismo en la zona

Les fistules anastomotiques (FA) post-colectomie au Service de Chirurgie Générale de l’Hôpital Aristide Le Dantec

La fistule anastomotique reste la complication la plus redoutée après chirurgie colorectale et continue à poser un problème diagnostique et thérapeutique. Le but de cette étude est de déterminer à la fois la prévalence et les éléments de prises en charge diagnostiques et  thérapeutiques de la fistule colique après colectomie. Nous avons mené une étude rétrospective descriptive des cas de fistule colique après  colectomie sur une période de 7 ans allant de janvier 2007 au décembre 2013. Il y avait 17 patients qui ont présenté une fistule colique parmi les 170 patients ayant bénéficié de colectomie dans notre service soit un taux de 10%. L'âge moyen au moment de l'intervention initiale était de 45,1 ans (extrêmes de 20 et 78 ans). Il y avait une prédominance des patients de sexe masculin (n=13) avec un sex ratio de 3,3. Les pathologies tumorales colorectales (n=9) et le volvulus de colon pelvien (n=7) était les principales indications de colectomie L'intervention initiale a été réalisée en urgence chez 13 patients. Le délai moyen d'apparition de la fistule était de 10,8 jours. Il y avait 10 patients ayant présenté une fistule colo-cutanée et 7 cas de péritonites postopératoires stercorales. Onze de nos patients présentaient une anémie (taux moyen d'hémoglobine de 9,1 g/dl) et 8 patients, une hyperleucocytose (taux moyen de 15100  leucocytes/mm3). Une échographie, réalisée chez 6 patients, était revenue normale chez 1 patient et avait mis en évidence un épanchement intra péritonéal chez 5 patients tandis que La tomodensitométrie (TDM) sans opacification digestive, réalisée chez 2 patients, n'était contributive au diagnostic que chez 1 seul patient. Neuf patients avaient bénéficié de traitement médical seul. Ce dernier consistait en une couverture  antibiotique, un régime hyperprotéique, et un appareillage de la fistule par une poche de colostomie. La fistule s'est fermée spontanément, dans un délai moyen de 15 jours. La reprise chirurgicale a été réaliséechez 8 patients dans un délai moyen de 4,8 jours. Elle a été indiquée pour une péritonite par fistule anastomotique chez 7 patients et pour  persistance de la fistule colocutanée malgré traitement médical chez 1 patient. Le geste chirurgical consistait en une stomie digestive dans 6 cas. Sept patients ont présenté au moins une complication liée à la fistule colique (2 récidives de la fistule, 3 suppurations et 2 éviscérations). La durée moyenne d'hospitalisation était de 55,2 jours (extrêmes de 15et 168 jours). Deux décès étaient enregistrés consécutif à un choc septique. Une accessibilité des moyens thérapeutiques telles que la nutrition parentérale et le drainage percutané nous permettrait de réduire une durée d'hospitalisation prolongée et également des coûts de prise en charge élevés.Mots clés: Colectomie, anastomose, fistule, péritonite, stomi

Bowel Anastomoses: Manual or Mechanical

An anastomosis is a connection between two tubular anatomical structures. Anastomoses have been a great surgical challenge from antiquities to modern times. Main research on the manual techniques and healing processes of digestive anastomoses took place during the 19th century. They were later improved by the advent of mechanical devices in the early 20th century. For both types of anastomoses, local and general conditions required for a good healing are the same. Many devices, both for manual and mechanical anastomoses have been developed. The devices’ uses depend on their availability, surgeons usual practice and the relative difficulty of the anastomosis. The debate is still lively about the advantages and the potential inconveniences of one technique versus the other in regards to many parameters such as operating time and the incidence of anastomotic leakage

Determinants of Success of the Young Entrepreneurship: Case of Young Financed by Fier in Segou Region

This research focuses on a less explored subject but one of considerable importance for the development of the Segou region, mainly the determinants of the success of young entrepreneurs. The objective of this research was to determine the success factors of entrepreneurs (entrepreneurial activities) financed by the FIER Project in the region of Segou. As part of this research, data were collected from a sample of 334 (three hundred and thirty-four) young entrepreneurs who are partners in the project.The results show that six (6) branches of activity were identified which are cattle fattening at 65.3%, followed by sheep fattening at 27.2%, cereal trade at 4.2%, goat breeding at 1.8 %, vegetable gardening at 1.2% ended by the trade of agricultural inputs 0.3%. Almost half of the entrepreneurs interviewed (46.1%) have more than 2 years of experience in their sector of activity, generally between 3 and 4 years. The DFS, partners of the young people in the sample, are CAECE JIGISEME, CVECA/ON, KAFO JIGINEW and NYESIGISO.The results of the logistic regression indicate that the motivation of young people to be their own boss, to value themselves, the experience in the activity, the financing of FIER and the Restitution of the amount received are significant at the threshold of 0.1%, 1 % and 5%. The Wald test confirms variables such as the motivation of the young person, the number of years in the activity, the structure of the financing, the personal contribution, the restitution and the start of production. Keyswords: Rural entrepreneurship, young, determinants, FIER, Segou, ACM. DOI: 10.7176/EJBM/15-6-02 Publication date:March 31st 202

Health facility-based prevalence and potential risk factors of autism spectrum disorders in Mali

Background: The prevalence of autism spectrum disorders (ASD) is 1-2% worldwide, 1 in 68 in the U.S, and unknown in Africa. ASD is under-diagnosed in Mali due to stigma and the lack of appropriate human resources and infrastructure.Objective: To determine the ASD frequency and potential risk factors in Mali.Methods: We identified all the health facilities and community-based organizations involved in the ASD diagnosis and management in Bamako. We established an ASD research and awareness platform in Mali, which encompasses community-based organizations and a multidisciplinary team including psychiatrists, psychologists, pediatricians, geneticists, and public health and social science specialists. Through this platform, we performed a survey in health facilities and organizations where patients with ASD are likely to seek care in Bamako. We reviewed the psychiatric patient registry to obtain basic epidemiological profiles of children with ASD, epilepsy and other psychiatric disorders.Results: We found a health facility-based prevalence of ASD of 4.5% (105/2,343) in Bamako. The mean age at the first outpatient visit was 7.64 ± 3.85 years old. First degree consanguinity of 29.5% (31/105) was more frequent in parents of ASD children versus age and sex matched controls OR= 4.37 [1.96-9.76] p=0.0001.Conclusion: Our data suggest that ASD is more common than expected in Mali. The established ASD awareness and research platform may improve the diagnosis and management of ASD by raising ASD awareness, training of Malian clinicians and researchers in early ASD screening and diagnosis, and strengthening research capacity in genomics of ASD and other mental disorders.Keywords: ASD, prevalence, consanguinity, health facilit

Ring vaccination with rVSV-ZEBOV under expanded access in response to an outbreak of Ebola virus disease in Guinea, 2016: an operational and vaccine safety report.

BACKGROUND: In March, 2016, a flare-up of Ebola virus disease was reported in Guinea, and in response ring vaccination with the unlicensed rVSV-ZEBOV vaccine was introduced under expanded access, the first time that an Ebola vaccine has been used in an outbreak setting outside a clinical trial. Here we describe the safety of rVSV-ZEBOV candidate vaccine and operational feasibility of ring vaccination as a reactive strategy in a resource-limited rural setting. METHODS: Approval for expanded access and compassionate use was rapidly sought and obtained from relevant authorities. Vaccination teams and frozen vaccine were flown to the outbreak settings. Rings of contacts and contacts of contacts were defined and eligible individuals, who had given informed consent, were vaccinated and followed up for 21 days under good clinical practice conditions. FINDINGS: Between March 17 and April 21, 2016, 1510 individuals were vaccinated in four rings in Guinea, including 303 individuals aged between 6 years and 17 years and 307 front-line workers. It took 10 days to vaccinate the first participant following the confirmation of the first case of Ebola virus disease. No secondary cases of Ebola virus disease occurred among the vaccinees. Adverse events following vaccination were reported in 47 (17%) 6-17 year olds (all mild) and 412 (36%) adults (individuals older than 18 years; 98% were mild). Children reported fewer arthralgia events than adults (one [<1%] of 303 children vs 81 [7%] of 1207 adults). No severe vaccine-related adverse events were reported. INTERPRETATION: The results show that a ring vaccination strategy can be rapidly and safely implemented at scale in response to Ebola virus disease outbreaks in rural settings. FUNDING: WHO, Gavi, and the World Food Programme

Expanding Research Capacity in Sub-Saharan Africa Through Informatics, Bioinformatics, and Data Science Training Programs in Mali

Bioinformatics and data science research have boundless potential across Africa due to its high levels of genetic diversity and disproportionate burden of infectious diseases, including malaria, tuberculosis, HIV and AIDS, Ebola virus disease, and Lassa fever. This work lays out an incremental approach for reaching underserved countries in bioinformatics and data science research through a progression of capacity building, training, and research efforts. Two global health informatics training programs sponsored by the Fogarty International Center (FIC) were carried out at the University of Sciences, Techniques and Technologies of Bamako, Mali (USTTB) between 1999 and 2011. Together with capacity building efforts through the West Africa International Centers of Excellence in Malaria Research (ICEMR), this progress laid the groundwork for a bioinformatics and data science training program launched at USTTB as part of the Human Heredity and Health in Africa (H3Africa) initiative. Prior to the global health informatics training, its trainees published first or second authorship and third or higher authorship manuscripts at rates of 0.40 and 0.10 per year, respectively. Following the training, these rates increased to 0.70 and 1.23 per year, respectively, which was a statistically significant increase (p &lt; 0.001). The bioinformatics and data science training program at USTTB commenced in 2017 focusing on student, faculty, and curriculum tiers of enhancement. The program’s sustainable measures included institutional support for core elements, university tuition and fees, resource sharing and coordination with local research projects and companion training programs, increased student and faculty publication rates, and increased research proposal submissions. Challenges reliance of high-speed bandwidth availability on short-term funding, lack of a discounted software portal for basic software applications, protracted application processes for United States visas, lack of industry job positions, and low publication rates in the areas of bioinformatics and data science. Long-term, incremental processes are necessary for engaging historically underserved countries in bioinformatics and data science research. The multi-tiered enhancement approach laid out here provides a platform for generating bioinformatics and data science technicians, teachers, researchers, and program managers. Increased literature on bioinformatics and data science training approaches and progress is needed to provide a framework for establishing benchmarks on the topics

Evolving trends in the management of acute appendicitis during COVID-19 waves. The ACIE appy II study

Background: In 2020, ACIE Appy study showed that COVID-19 pandemic heavily affected the management of patients with acute appendicitis (AA) worldwide, with an increased rate of non-operative management (NOM) strategies and a trend toward open surgery due to concern of virus transmission by laparoscopy and controversial recommendations on this issue. The aim of this study was to survey again the same group of surgeons to assess if any difference in management attitudes of AA had occurred in the later stages of the outbreak. Methods: From August 15 to September 30, 2021, an online questionnaire was sent to all 709 participants of the ACIE Appy study. The questionnaire included questions on personal protective equipment (PPE), local policies and screening for SARS-CoV-2 infection, NOM, surgical approach and disease presentations in 2021. The results were compared with the results from the previous study. Results: A total of 476 answers were collected (response rate 67.1%). Screening policies were significatively improved with most patients screened regardless of symptoms (89.5% vs. 37.4%) with PCR and antigenic test as the preferred test (74.1% vs. 26.3%). More patients tested positive before surgery and commercial systems were the preferred ones to filter smoke plumes during laparoscopy. Laparoscopic appendicectomy was the first option in the treatment of AA, with a declined use of NOM. Conclusion: Management of AA has improved in the last waves of pandemic. Increased evidence regarding SARS-COV-2 infection along with a timely healthcare systems response has been translated into tailored attitudes and a better care for patients with AA worldwide

Haematological consequences of acute uncomplicated falciparum malaria: a WorldWide Antimalarial Resistance Network pooled analysis of individual patient data

Background: Plasmodium falciparum malaria is associated with anaemia-related morbidity, attributable to host, parasite and drug factors. We quantified the haematological response following treatment of uncomplicated P. falciparum malaria to identify the factors associated with malarial anaemia. Methods: Individual patient data from eligible antimalarial efficacy studies of uncomplicated P. falciparum malaria, available through the WorldWide Antimalarial Resistance Network data repository prior to August 2015, were pooled using standardised methodology. The haematological response over time was quantified using a multivariable linear mixed effects model with nonlinear terms for time, and the model was then used to estimate the mean haemoglobin at day of nadir and day 7. Multivariable logistic regression quantified risk factors for moderately severe anaemia (haemoglobin < 7 g/dL) at day 0, day 3 and day 7 as well as a fractional fall ≥ 25% at day 3 and day 7. Results: A total of 70,226 patients, recruited into 200 studies between 1991 and 2013, were included in the analysis: 50,859 (72.4%) enrolled in Africa, 18,451 (26.3%) in Asia and 916 (1.3%) in South America. The median haemoglobin concentration at presentation was 9.9 g/dL (range 5.0–19.7 g/dL) in Africa, 11.6 g/dL (range 5.0–20.0 g/dL) in Asia and 12.3 g/dL (range 6.9–17.9 g/dL) in South America. Moderately severe anaemia (Hb < 7g/dl) was present in 8.4% (4284/50,859) of patients from Africa, 3.3% (606/18,451) from Asia and 0.1% (1/916) from South America. The nadir haemoglobin occurred on day 2 post treatment with a mean fall from baseline of 0.57 g/dL in Africa and 1.13 g/dL in Asia. Independent risk factors for moderately severe anaemia on day 7, in both Africa and Asia, included moderately severe anaemia at baseline (adjusted odds ratio (AOR) = 16.10 and AOR = 23.00, respectively), young age (age < 1 compared to ≥ 12 years AOR = 12.81 and AOR = 6.79, respectively), high parasitaemia (AOR = 1.78 and AOR = 1.58, respectively) and delayed parasite clearance (AOR = 2.44 and AOR = 2.59, respectively). In Asia, patients treated with an artemisinin-based regimen were at significantly greater risk of moderately severe anaemia on day 7 compared to those treated with a non-artemisinin-based regimen (AOR = 2.06 [95%CI 1.39–3.05], p < 0.001). Conclusions: In patients with uncomplicated P. falciparum malaria, the nadir haemoglobin occurs 2 days after starting treatment. Although artemisinin-based treatments increase the rate of parasite clearance, in Asia they are associated with a greater risk of anaemia during recovery