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This study investigates the controllability of a Volterra evolution equation with impulsive terms and nonlocal initial conditions. With the aid of the resolvent operator generated by the linear part of the equation, mild solutions can be defined. Notably, the resolvent operator lacks compactness and equicontinuity. Additionally, the compactness of the impulsive and nonlocal functions is not required. Sufficient conditions for controllability are obtained through measures of noncompactness in Banach spaces. Functional differential equations and hyperbolic partial differential equations can be solved with these results. An example is given to illustrate the validity of the presented results. [ABSTRACT FROM AUTHOR]

When the evolution family is hyperbolic and satisfies the Acquistapace-Terreni conditions, the existence and uniqueness of an almost automorphic mild solution and a weighted pseudo almost automorphic mild solution in distribution of mean-filed nonautonomous stochastic evolution equations driven by fractional Brownian motion is proved. Examples illustrating the main results are included. [ABSTRACT FROM AUTHOR]

BACKGROUND: Evolving climatic conditions impact the behavior of microorganisms. The lack of efficiency of beneficial microorganisms against pathogens can be due to these evolving abiotic factors more favorable to the development and adaptation of pathogens. It is therefore of great interest to understand their impact (especially temperature increase and relative humidity (RH) variation) on pathogenic and non‐pathogenic microorganisms. This work aimed to examine the possible effects of increasing temperature (20, 25, 30 and 33 °C) and RH (40%, 50%, 60% and 80%) on the growth and mycotoxin production (deoxynivalenol (DON) and zearalenone (ZEN)) of Fusarium graminearum, on the growth of three commercial biocontrol agents (BCAs; Mycostop®, Xedavir® and Polyversum®) and on the pathogen–BCA interaction. RESULTS: Results demonstrated that BCAs have contrasting impacts on the growth and mycotoxinogenesis of F. graminearum depending on abiotic factors. At 25 °C and regardless of RH, commercial BCAs limit DON production by F. graminearum, but at 30 °C and intermediate RH, Xedavir® is no longer effective. The ability of Xedavir® to control the production of ZEN production by F. graminearum is also affected by abiotic factors. However, increasing temperature has an opposite effect on its ability to control the accumulation of ZEN. Polyversum® oomycete is the BCA with the most resilient efficacy against F. graminearum toxinogenesis under the different abiotic factors. CONCLUSION: This work provides new knowledge of the effect of these abiotic parameters on the interaction between BCA and F. graminearum, especially on the production of mycotoxins. It paves the way for the development of efficient and resilient mycotoxin biocontrol strategies using beneficial microorganisms against F. graminearum, thus contributing to global food security. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Background: Vertical transmission of hepatitis C virus (HCV) is the primary cause of hepatitis C in the pediatric population. Nonetheless, only a small proportion of HCV-exposed children are tested. This study aimed to measure the proportion of HCV-exposed children tested and infected in Western New York and to identify factors influencing the odds of testing and infection in this population. Methods: This was a 11-year retrospective chart review study in which clinical, demographic, and behavioral data for HCV-exposed children and their mothers were collected. This period included year 2019 when a hepatitis C program began promoting early hepatitis C screening among infants born to mothers positive for hepatitis C. PCR-based detection of hepatitis C was used for children under 18 months of age and antibody testing for children above 18 months of age, followed by PCR if the antibody testing was positive. Logistic regression models were used to determine which characteristics associate with testing and infection status. Results: From a total of 133 children evaluated in clinic for hepatitis C from 2011 to 2021, 96.2% (128/133) were seen from 2019 to 2021. Among the 133 HCV-exposed children in our sample, 72.1% (96/133) were tested for HCV, 62.4% (83/133) were tested by PCR, 9.0% (12/133) tested by antibody, and 5.2% (5/95) of those tested were infected. Only one child out of 12 was positive for hepatitis C antibody yet, subsequent PCR testing was negative in this child. Among all five hepatitis C infected children, four were diagnosed with neonatal abstinence syndrome, five had maternal history of illicit drug use, one had maternal history of HIV infection, and all of them were identified after the hepatitis C program open in 2019. The odds of a child being tested were lower for those accompanied by their biological mother at their clinic visit (odds ratio, 0.16; 95% CI, 0.06–0.45). Conclusions: Screening programs on hepatitis C vertical transmission improved detection of hepatitis C among exposed children. The proportion of children born to mothers with hepatitis C in Western New York that were positive for hepatitis C was 5.2%, suggesting that similar proportion of exposed infants born before 2019 were lost for follow up. [ABSTRACT FROM AUTHOR]

In this work, we prove strong convergence on small time interval of order 1 / 2 − ϵ for arbitrarily small ϵ > 0 of the Euler-Maruyama approximation for additive Brownian motion with Hölder continuous drift satisfying a linear growth condition. The proof is based on direct estimations of functional of the Euler-Maruyama approximation. The order of convergence does not depend on the Hölder index of the drift, thus generalizing the results obtained in [10] to both Linear growth and to an optimal convergence order. [ABSTRACT FROM AUTHOR]

Problem Like most low- and middle-income countries, Viet Nam has a scarcity of rehabilitation professionals and lacks training programmes that meet international standards. Approach In 2018, four Vietnamese medical universities, the Université Catholique de Louvain, the Université Libre de Bruxelles, the Humanity & Inclusion charity and World Physiotherapy agreed to collaborate on strengthening pre-service education for physiotherapists in the country. Local setting Viet Nam has a favourable environment for nurturing rehabilitation services and education: development funds have been available; government investment is increasing; and rehabilitation education has existed for many decades. Relevant changes The collaboration resulted in the establishment of: (i) a 4-year, competency-based, entry-level curriculum for physiotherapists (bachelor's degree); (ii) opportunities for continuing professional development; (iii) a 2-year master's programme for physiotherapy lecturers and clinical supervisors; and (iv) a national physiotherapy association. In addition, four students were supported in studying for PhD degrees. Strong collaboration and comprehensive and complementary interventions have laid the foundations for sustainable, high-quality, educational programmes for physiotherapists, which will improve access to, and the standard of, rehabilitation services in Viet Nam, thereby leading to better patient outcomes. Lessons learnt Curricula for entry-level physiotherapy programmes should be competency-based, be actively managed by national educators and meet international standards while being responsive to local priorities. To strengthen the rehabilitation workforce, educators involved in teaching and supervising training programmes should have the skills and knowledge required. A national professional physiotherapy association should be established to provide continuing professional development for physiotherapists and to take part in international collaborations. [ABSTRACT FROM AUTHOR]

In this paper, we study the existence and continuous dependence on coefficients of mild solutions for first-order McKean–Vlasov integrodifferential equations with delay driven by a cylindrical Wiener process using resolvent operator theory and Wasserstein distance. Under the situation that the nonlinear term depends on the probability distribution of the state, the existence and uniqueness of solutions are established. An example illustrating the general results is included. [ABSTRACT FROM AUTHOR]

Salmonella enterica is the most common foodborne pathogen worldwide. It causes two types of diseases, a self-limiting gastroenteritis and an invasive, more threatening, infection. Salmonella gastroenteritis is caused by several serotypes and is common worldwide. In contrast, invasive salmonellosis is rare in high-income countries (HIC) while frequent in low- and middle-income countries (LMIC), especially in sub-Saharan Africa (sSA). Invasive Nontyphoidal Salmonella (iNTS), corresponding to serotypes other than Typhi and Paratyphi, have emerged in sSA and pose a significant risk to public health. We conducted a whole-genome sequence (WGS) analysis of 72 strains of Salmonella isolated from diarrheic human patients and chicken meat sold in multipurpose markets in Dakar, Senegal. Antimicrobial susceptibility testing combined with WGS data analysis revealed frequent resistance to fluoroquinolones and the sulfamethoxazole-trimethoprim combination that are among the most used treatments for invasive Salmonella. In contrast, resistance to the historical first-line drugs chloramphenicol and ampicillin, and to cephalosporins was rare. Antimicrobial resistance (AMR) was lower in clinical isolates compared to chicken strains pointing to the concern posed by the excessive use of antimicrobials in farming. Phylogenetic analysis suggested possible transmission of the emerging multidrug resistant (MDR) Kentucky ST198 and serotype Schwarzengrund from chicken to human. These results stress the need for active surveillance of Salmonella and AMR in order to address invasive salmonellosis caused by nontyphoidal Salmonella strains and other important bacterial diseases in sSA. [ABSTRACT FROM AUTHOR]

The aim of this study was to develop a set of experiments to screen and decipher the mechanisms of biocontrol agents (BCAs), isolated from commercial formulation, against two major mycotoxigenic fungi in cereals, Fusarium graminearum and Fusarium verticillioides. These two phytopathogens produce mycotoxins harmful to human and animal health and are responsible for the massive use of pesticides, for the protection of cereals. It is therefore essential to better understand the mechanisms of action of alternative control strategies such as the use of BCAs in order to optimize their applications. The early and late stages of interaction between BCAs and pathogens were investigated from germination of spores to the effects on perithecia (survival form of pathogen). The analysis of antagonist activities of BCAs revealed different strategies of biocontrol where chronological, process combination and specialization aspects of interactions are discussed. Streptomyces griseoviridis main strategy is based on antibiosis with the secretion of several compounds with anti-fungal and anti-germination activity, but also a mixture of hydrolytic enzymes to attack pathogens, which compensates for an important deficit in terms of spatial colonization capacity. It has good abilities in terms of nutritional competition. Trichoderma asperellum is capable of activating a very wide range of defenses and attacks combining the synthesis of various antifungal compounds (metabolite, enzymes, VOCs), with different targets (spores, mycelium, mycotoxins), and direct action by mycoparasitism and mycophagy. Concerning Pythium oligandrum, its efficiency is mainly due to its strong capacity to colonize the environment, with a direct action via microbial predation, stimulation of its reproduction at the contact of pathogens and the reduction of perithecia formation. [ABSTRACT FROM AUTHOR]

The actinobacteria Streptomyces sp. AV05 appears to be a potential biocontrol agent (BCA) against mycotoxigenic fungi. It was found to significantly inhibit F. verticillioides growth and mycotoxin production during their co-cultivation. F. verticillioides growth was durably affected while the decrease of the toxin production levels was reversible, suggesting different BCA actions. The study of both transcriptomes brought useful information on the microbial interaction. RNA-seq data indicated that the dual interaction modified genetic expression of both microorganisms as 18.5 % of the genes were differentially expressed for the fungus against 3.8 % for the actinobacteria. Fungal differentially expressed genes (DEGs) were equally up and down regulated while bacterial ones were mainly upregulated. We especially focused the analysis of DEGs on fungal defense reaction to bacterial attack. For example, if this potential BCA implements a strategy of antibiosis with the over expression of 'siderophore-interacting protein' linked to the production of bacteriocins, the fungus in a state of stress is able to adapt its metabolism by up-regulation of amidase. It could correspond to the induction of resistance gene clusters and suggest a detoxification process. Moreover fumonisins-related pathway appears underexpressed in the presence of Streptomyces that explain the reduction of fumonisin accumulation observed. • Fusarium verticillioides is a mycotoxigenic fungus contaminating cereal crop. • Streptomyces sp. AV05 is a potential BCA for F. verticillioides. • Transcriptome study help to understand antagonistic mechanisms. • Fusarium transcriptome is more impacted by confrontation than Streptomyces one. [ABSTRACT FROM AUTHOR]

Located in the south of Senegal, the Upper-Casamance (present-day Kolda region) has a strong vegetation dynamic mainly due to the clearing of land for agricultural needs, bush fires, population growth and uncontrolled logging. In such a situation, mapping and quantification of changes in vegetation cover become relevant for a more rational and sustainable management of plant resources, but also for the achievement of the Sustainable Development Goals. This study aims to detect the degradation and regeneration of vegetation cover during the last two decades in Upper-Casamance. It is based on an analysis of the trends of MODIS NDVI images time series acquired over the period 2000-2018, on a land cover and use changes (LULCC) maps established from Landsat images (ETM+ 1999 and OLI 2018), and a joint analysis of NDVI and LULCC trends. Data processing is based on the calculation of the Kendall correlation (τ) and the p significance test at the 10% threshold, and on a multistage unsupervised classification, respectively. The study shows significant changes in land cover and land use, including conversion from forest to savannah (13.5%), and from savannah to crop and habitat areas (7.9%). Significant negative trends in NDVI (related to forest-savanna conversion and forest-cropping and habitat areas) are observed in 2.1% of the study area and indicate vegetation degradation especially along the border with Gambia, on the Pata-Ndorna axis, in the centre of the study area, and around Medina Gounass. On the other hand, significant positive trends on 1.8% of the study area are evidence of regeneration in the south and are linked to the conversion of cultivated areas into savanna and forest. Joint analysis of NDVI and LULCC trends indicated significant degradation in south of Kerewane and Niaming, on the Ndorna-Pata axis, around Medina Gounass, and towards Saré Coly; and significant regeneration at the northeast border, north of Mampatim, to the south towards Bagadadji and Medina El Hadji, and between Linkering-Paroumba. This analysis also revealed that the two sources of data (NDVI et Landsat) are spatially consistent and that most of the trends in vegetation productivity are explained by changes in land use and not by climate. [ABSTRACT FROM AUTHOR]

Background: Population-wide interventions using malaria testing and treatment might decrease the reservoir of Plasmodium falciparum infection and accelerate towards elimination. Questions remain about their effectiveness and evidence from different transmission settings is needed. Methods: A pilot quasi-experimental study to evaluate a package of population-wide test and treat interventions was conducted in six health facility catchment areas (HFCA) in the districts of Kanel, Linguère, and Ranérou (Senegal). Seven adjacent HFCAs were selected as comparison. Villages within the intervention HFCAs were stratified according to the 2013 incidences of passively detected malaria cases, and those with an incidence ≥ 15 cases/1000/year were targeted for a mass test and treat (MTAT) in September 2014. All households were visited, all consenting individuals were tested with a rapid diagnostic test (RDT), and, if positive, treated with dihydroartemisinin-piperaquine. This was followed by weekly screening, testing and treatment of fever cases (PECADOM++) until the end of the transmission season in January 2015. Villages with lower incidence received only PECADOM++ or case investigation. To evaluate the impact of the interventions over that transmission season, the incidence of passively detected, RDT-confirmed malaria cases was compared between the intervention and comparison groups with a difference-in-difference analysis using negative binomial regression with random effects on HFCA. Results: During MTAT, 89% (2225/2503) of households were visited and 86% (18,992/22,170) of individuals were tested, for a combined 77% effective coverage. Among those tested, 291 (1.5%) were RDT positive (range 0–10.8 by village), of whom 82% were < 20 years old and 70% were afebrile. During the PECADOM++ 40,002 visits were conducted to find 2784 individuals reporting fever, with an RDT positivity of 6.5% (170/2612). The combination of interventions resulted in an estimated 38% larger decrease in malaria case incidence in the intervention compared to the comparison group (adjusted incidence risk ratio = 0.62, 95% CI 0.45–0.84, p = 0.002). The cost of the MTAT was $14.3 per person. Conclusions: It was operationally feasible to conduct MTAT and PECADOM++ with high coverage, although PECADOM++ was not an efficient strategy to complement MTAT. The modest impact of the intervention package suggests a need for alternative or complementary strategies. [ABSTRACT FROM AUTHOR]

Background: Malaria surveillance requires powerful tools and strategies to achieve malaria elimination. Rapid diagnostic tests for malaria (RDTs) are easily deployed on a large scale and are helpful sources of parasite DNA. The application of sensitive molecular techniques to these RDTs is a modern tool for improving malaria case detection and drug resistance surveillance. Several studies have made it possible to extract the DNA of Plasmodium falciparum from RDTs. The knowledge of gametocyte carriage in the population is important to better assess the level of parasite transmission in elimination settings. The aim of this study was to detect P. falciparum gametocytes from used RDTs by quantitative PCR for molecular monitoring of malaria transmission. Methods: DNA was extracted from 303 RDT devices (SD Bioline Malaria Pf) using the Chelex-100 protocol. qPCR was performed in a 20 μL reaction to detect and quantify transcripts of the pfs25 gene. The cycle threshold (Ct) was determined by the emission fluorescence corresponding to the initial amount of amplified DNA. Results: The study found an overall prevalence of 53.47% with an average Ct of 32.12 ± 4.28 cycles. In 2018, the prevalence of gametocytes was higher in the Ranérou district (76.24%) than in the Saint-Louis district (67.33%) where an increase in the number of gametocyte carriers in 2018 was noted, in comparison with 2017. Conclusions: RDTs are a good source of DNA for molecular monitoring of gametocyte carriage. This method is a simple and effective tool to better understand the level of malaria transmission with a view to elimination. [ABSTRACT FROM AUTHOR]

This work deals with the influence of envelope thickness and solar absorption on the time lag and the decrement factor. For this, a test cell of 1 m3 of volume is built with a material commonly used in construction in Senegal, the compressed earth brick stabilized with cement. The ambient-air temperature inside and outside of test cell and solar direct normal irradiance is measured. The test cell is modeled using EnergyPlus software. The comparison of experimental and theoretical ambient-air temperature puts out a great linear showing the reliability of the model. The time lag and the decrement factor are calculated using the air-sol equivalent temperature of the test cell and the inside ambient-air temperature. The time lag and decrement factor of the compressed stabilized earth brick envelope are respectively 0.22 and 6.6 h showing the good thermal inertia of those bricks. A parametric study is performed to determine the effect of envelope thickness and solar absorptivity on the time lag and decrement factor. The results show that the decrement factor decreases with envelope thickness while the time lag increases linearly and that an envelope thickness of 32 cm has a decrement factor of around zero with a maximum time lag of about 12 h for this type of material. The envelope's solar absorption has a moderate effect on the decrement factor and time lag. [ABSTRACT FROM AUTHOR]

In this work, we study the asymptotic behavior of the mild solutions of a class of stochastic partial functional integrodifferential equation on Hilbert spaces. Using the stochastic convolution developed, we establish the exponential stability in p − mean square with p ≥ 2. Also, pathwise exponential stability is proved for p> 2. We extend the result of an example is provided for illustration. [ABSTRACT FROM AUTHOR]

Nearly half the world’s population burns solid fuel for cooking, heating, and lighting. The incomplete combustion of these fuels is associated with detrimental health and environmental effects. The design and distribution of improved cookstoves that increase combustion efficiency and reduce indoor air pollution are a global priority. However, promoting exclusive and sustainable use of the improved stoves has proved challenging. In 2012, we conducted a survey in a community in rural Senegal to describe stove ownership and preferences for different stove technologies. This report aims to describe local stove and fuel use, to identify household preferences related to stove features and function, and to elicit the community perceptions of cleaner-burning stove alternatives with a focus on liquid propane gas. Similar to many resource-limited settings, biomass fuel use was ubiquitous and multiple stoves were used, even when cleaner burning alternatives were available; less than 1% of households that owned a liquid propane stove used it as the primary cooking device. Despite nearly universal use of the traditional open fire (92% of households), women did not prefer this stove when presented with other options. Propane gas, solar, and improved cookstoves were all viewed as more desirable when compared to the traditional open fire, however first-hand experience and knowledge of these stoves was limited. The stove features of greatest value were, in order: large cooking capacity, minimal smoke production, and rapid heating. Despite the low desirability and smoke emisions from the traditional open fire, its pervasive use, even in the presence of alternative stove options, may be related to its ability to satisfy the practical needs of the surveyed cooks, namely large cooking capacity and rapid, intense heat generation. Our data suggest women in this community want alternative stove options that reduce smoke exposure, however currently available stoves, including liquid propane gas, do not address all of the cooks’ preferences. [ABSTRACT FROM AUTHOR]

In this work, we develop the necessary conditions of optimality for partially observed control problems governed by stochastic integrodifferential equations of neutral type on Hilbert spaces driven by relaxed controls. Under suitable conditions, we establish the existence and the uniqueness of mild solution which has a continuous modification. We prove the continuity of the control to the solution map. Then we consider an optimal control problem of Bolza type. Using these results we give necessary conditions of optimality for a class of stochastic integrodifferential equations of neutral type on Hilbert spaces. [ABSTRACT FROM AUTHOR]

Malaria infection is a multifactorial disease partly modulated by host immuno-genetic factors. Recent evidence has demonstrated the importance of Interleukin-17 family proinflammatory cytokines and their genetic variants in host immunity. However, limited knowledge exists about their role in parasitic infections such as malaria. We aimed to investigate IL-17A serum levels in patients with severe and uncomplicated malaria and gene polymorphism's influence on the IL-17A serum levels. In this research, 125 severe (SM) and uncomplicated (UM) malaria patients and 48 free malaria controls were enrolled. IL-17A serum levels were measured with ELISA. PCR and DNA sequencing were used to assess host genetic polymorphisms in IL-17A. We performed a multivariate regression to estimate the impact of human IL-17A variants on IL-17A serum levels and malaria outcomes. Elevated serum IL-17A levels accompanied by increased parasitemia were found in SM patients compared to UM and controls (P < 0.0001). Also, the IL-17A levels were lower in SM patients who were deceased than in those who survived. In addition, the minor allele frequencies (MAF) of two IL-17A polymorphisms (rs3819024 and rs3748067) were more prevalent in SM patients than UM patients, indicating an essential role in SM. Interestingly, the heterozygous rs8193038 AG genotype was significantly associated with higher levels of IL-17A than the homozygous wild type (AA). According to our results, it can be concluded that the IL-17A gene rs8193038 polymorphism significantly affects IL-17A gene expression. Our results fill a gap in the implication of IL-17A gene polymorphisms on the cytokine level in a malaria cohort. IL-17A gene polymorphisms also may influence cytokine production in response to Plasmodium infections and may contribute to the hyperinflammatory responses during severe malaria outcomes. [ABSTRACT FROM AUTHOR]

As effective onchocerciasis control efforts in Africa transition to elimination efforts, different diagnostic tools are required to support country programs. Senegal, with its long standing, successful control program, is transitioning to using the SD BIOLINE Onchocerciasis IgG4 (Ov16) rapid test over traditional skin snip microscopy. The aim of this study is to demonstrate the feasibility of integrating the Ov16 rapid test into onchocerciasis surveillance activities in Senegal, based on the following attributes of acceptability, usability, and cost. A cross-sectional study was conducted in 13 villages in southeastern Senegal in May 2016. Individuals 5 years and older were invited to participate in a demographic questionnaire, an Ov16 rapid test, a skin snip biopsy, and an acceptability interview. Rapid test technicians were interviewed and a costing analysis was conducted. Of 1,173 participants, 1,169 (99.7%) agreed to the rapid test while 383 (32.7%) agreed to skin snip microscopy. The sero-positivity rate of the rapid test among those tested was 2.6% with zero positives 10 years and younger. None of the 383 skin snips were positive for Ov microfilaria. Community members appreciated that the rapid test was performed quickly, was not painful, and provided reliable results. The total costs for this surveillance activity was $22,272.83, with a cost per test conducted at $3.14 for rapid test, $7.58 for skin snip microscopy, and $13.43 for shared costs. If no participants had refused skin snip microscopy, the total cost per method with shared costs would have been around $16 per person tested. In this area with low onchocerciasis sero-positivity, there was high acceptability and perceived value of the rapid test by community members and technicians. This study provides evidence of the feasibility of implementing the Ov16 rapid test in Senegal and may be informative to other country programs transitioning to Ov16 serologic tools. [ABSTRACT FROM AUTHOR]

In this work, we consider the question of controllability of a class of integrodifferential equations on Hilbert space with measures as controls. We assume that the linear part has a resolvent operator in the sense given by R. Grimmer. We generalize the original work of N. Ahmed on vector measures, and we use it to develop necessary and sufficient conditions for weak and the exact controllability of the integrodifferential equation. Using the latter, we prove that exact controllability of the integrodifferential equation implies exact controllability of a perturbed integrodifferential equation. Controllability problem for the perturbed system is formulated fixed point problem in the space of vector measures. Our results cover impulsive controls as well as regular controls. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Abstract: Laboratory follow-up of HIV patients in resource-limited settings requires appropriate instruments for CD4 T cell enumeration. In this study, we evaluated the application of a simplified, mobile and robust flow cytometry system, the Apogee Auto 40 analyzer (Auto40) using thermoresistant reagents, for CD4 T cell enumeration. We measured the absolute CD4 counts in fresh whole blood samples from 170 Senegalese subjects, including 129 HIV-positive (HIV+) patients and 41 HIV-negative (HIV−) controls. Based on volumetric primary CD4 gating, cells were stained with commercially available reagents (Easy MoAb CD4;Bio-D, Valenzano, Italy) and analyzed on the Auto40. The results were compared with those from the FACSCount system (Becton Dickinson, San Jose, USA). Repeatability analysis was performed on duplicate testing of 49 samples on both FACSCount and Auto40. The intra-run precision was measured by 10 replicates using 3 clinical blood samples with low, intermediate and high CD4 concentrations. The results from the two instruments were in good agreement. The percent similarity between the results of both instruments was 99%±relative standard deviation of 12.7%. The concordance correlation coefficient was 0.99. The absolute bias and limits of agreement (LOA) between the two instruments, calculated by Bland–Altman analysis, were clinically acceptable (bias: +4 cells/μl; LOA: −111 to +120 cells/μl). The clinical agreement between the two instruments at a cutoff of 200 CD4 cells/μl was 94%. The repeatability of measurements on the Auto40 was also similar to that observed with FACSCount system (bias +0.1 cells/μl, coefficient of variation 2.5% vs bias −1.1cells/μl, coefficient of variation 2.9% respectively). In conclusion, our results indicate that the Auto 40 system, using thermoresistant reagents, is suitable for CD4 T cell enumeration and will be a helpful tool to improve HIV laboratory monitoring in resource-limited settings. [Copyright &y& Elsevier]

Background: The use of artemisinin as a monotherapy resulted in the emergence of artemisinin resistance in 2005 in Southeast Asia. Monitoring of artemisinin combination therapy (ACT) is critical in order to detect and prevent the spread of resistance in endemic areas. Ex vivo studies and genotyping of molecular markers of resistance can be used as part of this routine monitoring strategy. One gene that has been associated in some ACT partner drug resistance is the Plasmodium falciparum multidrug resistance protein 1 (pfmdr1) gene. The purpose of this study was to assess the drug susceptibility of P. falciparum populations from Thiès, Senegal by ex vivo assay and typing molecular markers of resistance to drug components of ACT currently used for treatment. Methods: The ex vivo susceptibility of 170 P. falciparum isolates to chloroquine, amodiaquine, lumefantrine, artesunate, and artemether was determined using the DAPI ex vivo assay. The high resolution melting technique was used to genotype the pfmdr1 gene at codons 86, 184 and 1246. Results: A significant decrease in IC50 values was observed between 2012 and 2013: from 13.84 to 6.484 for amodiaquine, 173.4 to 113.2 for lumefantrine, and 39.72 to 18.29 for chloroquine, respectively. Increase of the wild haplotype NYD and the decrease of the mutant haplotype NFD (79 and 62.26 %) was also observed. A correlation was observed between the wild type allele Y184 in pfmdr1 and higher IC50 for all drugs, except amodiaquine. Conclusion: This study has shown an increase in sensitivity over the span of two transmission seasons, marked by an increase in the WT alleles at pfmdr1. Continuous the monitoring of the ACT used for treatment of uncomplicated malaria will be helpful. [ABSTRACT FROM AUTHOR]

Objectives: To describe severe malaria cases with bacterial infection. Patients and Methods: we conduct a prospective, descriptive and analytical study during 8 months. Results: Fifteen of the 86 severe malaria cases had bacterial infections: enteritis (7 cases), urinary tract infection (4 cases), meningitis (4 cases), pneumonia (cases), sepsis (1 case), and sinusitis (1 case). Convulsions, jaundice, abnormal bleeding, pulmonary edema were more frequent in patients with associated infections. The average number of leukocytes and CRP were significantly higher in patients with bacterial infection. The mean parasite density was higher in patients without bacterial infection (56,362 / mm3 vs. 239,162.2 ± 3326 / mm 3 ± 7175.3). Lethality was higher in patients with bacterial infection (20% against 16.9%). Conclusion: Bacterial infections are common in severe malaria and may influence the prognosis. [ABSTRACT FROM AUTHOR]

• The existence and the uniqueness of mild solutions of random integrodifferential equations are studied • We develop a new tool in the resolvent operator theory and apply several fixed-point theorems • We establish the properties of mean-square stability and attractiveness • We apply the theoretical outcomes to a type of the Heath-Jarrow-Morton-Musiela (HJMM) equation In this paper, the existence and the uniqueness of mild solutions of random integrodifferential equations are studied. To obtain random solutions, we develop a new tool in the resolvent operator theory and apply several fixed-point theorems. In addition, we establish the properties of mean-square stability and attractiveness. In the end, examples are worked out and we apply the theoretical outcomes to a type of the Heath-Jarrow-Morton-Musiela (HJMM) equation. [ABSTRACT FROM AUTHOR]

Helicobacter pylori (H. pylori) is a major gastric pathogen that has been associated with humans for more than 60,000 years. H. pylori causes different gastric diseases including dyspepsia, ulcers and gastric cancers. Disease development depends on several factors including the infecting H. pylori strain, environmental and host factors. Another factor that might influence H. pylori colonization and diseases is the gastric microbiota that was overlooked for long because of the belief that human stomach was a hostile environment that cannot support microbial life. Once established, H. pylori mainly resides in the gastric mucosa and interacts with the resident bacteria. How these interactions impact on H. pylori-caused diseases has been poorly studied in human. In this study, we analyzed the interactions between H. pylori and two bacteria, Streptocccus mitis and Lactobacillus fermentum that are present in the stomach of both healthy and gastric disease human patients. We have found that S. mitis produced and released one or more diffusible factors that induce growth inhibition and coccoid conversion of H. pylori cells. In contrast, both H. pylori and L. fermentum secreted factors that promote survival of S. mitis during the stationary phase of growth. Using a metabolomics approach, we identified compounds that might be responsible for the conversion of H. pylori from spiral to coccoid cells. This study provide evidences that gastric bacteria influences H. pylori physiology and therefore possibly the diseases this bacterium causes. [ABSTRACT FROM AUTHOR]

Background In Martinique, prostate cancer incidence rates have been increasing since the 1980s and are actually among the highest worldwide. Exposure to lifestyle (changes in dietary habits), environmental factors (exposure to organochlorine pesticides) and modifications in diagnostic and screening procedures, are favored etiological hypotheses. The aim of the present study is to describe and interpret prostate cancer incidence trends over the past 25 years (1981-2005) in Martinique. Methods Data on incident prostate cancer cases from 1981 to 2005 were obtained from the populationbased Martinique Cancer Registry. World age-standardised incidence rates were calculated and an age-period-cohort model was used to determine average annual variations for prostate cancer during the study period. Age and period effects were assessed, employing the method proposed by Clayton and Schifflers. Relative changes in prostate cancer incidence, at fiveyear intervals between 1981 and 2005, were also studied with an organochlorine pesticide exposure index, built as a proxy of the relative intensity of chlordecone use on the island between 1973 and 1993. Results Prostate cancer incidence was found to increase by 5.07% annually between 1981 and 2005. Compared to 1981-1985, prostate cancer relative risk, in men aged 50-74 years and 75 years and above was respectively 5.98% and 3.07% from 2001 to 2005. An inverse association between population pesticide exposure levels and prostate cancer risk was also highlighted, with highest prostate cancer incidences observed in urban zones showing the lowest soil contamination levels by the chlordecone pesticide (zone 1). Conclusion No conclusive association was found between the intensity of pesticide use and the subsequent rise in prostate cancer incidence. However, it remains necessary to develop and reinforce continuous monitoring of prostate cancer incidence and mortality trends on the island. Further studies are also needed in order to consider other risk factors such as modifications in diagnostic and screening procedures over the last 25 years. [ABSTRACT FROM AUTHOR]

Tuberculosis (TB) is a global public health problem exacerbated by the HIV epidemic. Here we evaluate a candidate TB vaccine, MVA85A, in a Phase I study in HIV-infected adults in Senegal. 24 patients were enrolled: Group 1∶12, antiretroviral therapy (ART) naïve, adults, with CD4 counts >300 and HIV RNA load <100 000 copies/ml. Group 2∶12 adults, stable on ART, with CD4 counts >300, and an undetectable HIV RNA load. Safety was evaluated by occurrence of local and systemic adverse events (AEs) and by monitoring of CD4 count, HIV RNA load, haematology and biochemistry. Immunogenicity was evaluated by ex-vivo interferon-gamma ELISpot assay. 87.7% of AEs were mild; 11.6% were moderate; and 0.7% were severe. 29.2% of AEs were systemic; 70.8% were expected local AEs. There were no vaccine-related Serious Adverse Events (SAEs) or clinically significant effects on HIV RNA load or CD4 count. In ART naive subjects, the first MVA85A immunisation induced a significant immune response at 1 and 4 weeks post-immunisation, which contracted to baseline by 12 weeks. Durability of immunogenicity in subjects on ART persisted out to 24 weeks post-vaccination. A second dose of MVA85A at 12 months enhanced immunogenicity in ART naïve subjects. Subjects on ART had higher responses after the first vaccination compared with ART naïve subjects; responses were comparable after 2 immunisations. In conclusion, MVA85A is well-tolerated and immunogenic in HIV-infected subjects in Senegal. A two dose regimen in ART naïve subjects is comparable in immunogenicity to a single dose in subjects on ART. Clinicaltrials.gov trial identifier NCT00731471. [ABSTRACT FROM AUTHOR]

Background Malaria treatment efforts are hindered by the rapid emergence and spread of drug resistant parasites. Simple assays to monitor parasite drug response in direct patient samples (ex vivo) can detect drug resistance before it becomes clinically apparent, and can inform changes in treatment policy to prevent the spread of resistance. Methods Parasite drug responses to amodiaquine, artemisinin, chloroquine and mefloquine were tested in approximately 400 Plasmodium falciparum malaria infections in Thiès, Senegal between 2008 and 2011 using a DAPI-based ex vivo drug resistance assay. Drug resistance-associated mutations were also genotyped in pfcrt and pfmdr1. Results Parasite drug responses changed between 2008 and 2011, as parasites became less sensitive to amodiaquine, artemisinin and chloroquine over time. The prevalence of known resistanceassociated mutations also changed over time. Decreased amodiaquine sensitivity was associated with sustained, highly prevalent mutations in pfcrt, and one mutation in pfmdr1 - Y184F - was associated with decreased parasite sensitivity to artemisinin. Conclusions Directly measuring ex vivo parasite drug response and resistance mutation genotyping over time are useful tools for monitoring parasite drug responses in field samples. Furthermore, these data suggest that the use of amodiaquine and artemisinin derivatives in combination therapies is selecting for increased drug tolerance within this population. [ABSTRACT FROM AUTHOR]

Immune activation has been suggested to increase susceptibility to human immunodeficiency virus type 1 (HIV-1) transmission, while at the same time it could be deemed essential for mounting an effective antiviral immune response. In this study, we compared levels of T cell activation between exposed seronegative (ESN) partners in HIV-1 discordant couples and HIV-unexposed control subjects in Dakar, Senegal. ESN subjects showed lower levels of CD38 expression on CD4(+) T cells than did control subjects. However, this was found to be associated with concurrent differences in the use of condoms: ESN subjects reported a higher degree of condom use than did control subjects, which correlated inversely with CD38 expression. In addition, we observed markedly higher levels of T cell activation in women compared with men, irrespective of sexual behavior. These findings question the relevance of low-level CD4(+) T cell activation in resistance to HIV-1 infection and underscore the need to take gender and sexual behavior characteristics of high-risk populations into account when analyzing correlates of protective immunity. [ABSTRACT FROM AUTHOR]

Immune activation has been suggested to increase susceptibility to human immunodeficiency virus type 1 (HIV-1) transmission, while at the same time it could be deemed essential for mounting an effective antiviral immune response. In this study, we compared levels of T cell activation between exposed seronegative (ESN) partners in HIV-1 discordant couples and HIV-unexposed control subjects in Dakar, Senegal. ESN subjects showed lower levels of CD38 expression on CD4+ T cells than did control subjects. However, this was found to be associated with concurrent differences in the use of condoms: ESN subjects reported a higher degree of condom use than did control subjects, which correlated inversely with CD38 expression. In addition, we observed markedly higher levels of T cell activation in women compared with men, irrespective of sexual behavior. These findings question the relevance of low-level CD4+ T cell activation in resistance to HIV-1 infection and underscore the need to take gender and sexual behavior characteristics of high-risk populations into account when analyzing correlates of protective immunity. [ABSTRACT FROM AUTHOR]

West Africa is shifting towards an increasing liberalization of agricultural markets. This trend will continue in line with current trade negotiations at the World Trade Organization (WTO) and between the European Union and African, Caribbean and Pacific (ACP) countries. The objective of this paper is to assess the impact of these negotiations on the livestock sector in the region. Livestock systems, in spite of their technical weakness, are strongly integrated with markets. Liberalization has had an important impact on national livestock sectors, especially dairying and poultry production. Imports of poultry meat increased, for example, from 500 to 17,000 tonnes between 1996 and 2002 in Senegal. Similar changes have been seen in Ghana and Ivory Coast. The dairy sector has had to compete with milk powder imports for years, but this competition seems to be limited by market segmentation, which explains the recent good prospects for local milk production. In addition, powdered milk production has had a significant role in the establishment of a local dairy industry. African countries should invest further in trade negotiations if they are to increase national capacities, eg via improvements in the negotiating power of administration services and the encouragement of national and regional research networks for market analysis. [ABSTRACT FROM AUTHOR]

Background: The type III secretion system (TTSS) is an important virulence determinant of Gram-negative bacterial pathogens. It enables the injection of effector proteins into the cytosol of eukaryotic cells. These effectors ultimately manipulate the cellular functions of the infected organism. Salmonella enterica serovar Typhimurium encodes two virulence associated TTSSs encoded by the Salmonella Pathogenicity Islands (SPI) 1 and 2 that are required for the intestinal and systemic phases of the infection, respectively. However, recent studies suggest that the roles of these TTSSs are not restricted to these compartments. The regulation of TTSSs in Salmonella is very complex with several regulators operating to activate or to repress expression depending on the environmental conditions. Results: We performed a systematic analysis of the regulation of type III effectors during growth in vitro. We have tested the ability of seven regulatory genes to regulate ten effector genes. Each regulator was expressed in the absence of the other six to avoid cascade effects. Our results confirm and extend the previously reported regulation of TTSS1 and TTSS2 effectors by InvFSicA and SsrB respectively. Conclusion: The set of strains constructed for this study can be used to quickly and systematically study the regulation of newly identified effector genes of Salmonella enterica. The approach we have used can also be applied to study complex regulatory cascades in other bacterial species. [ABSTRACT FROM AUTHOR]

La rétrocession des antirétroviraux fait partie du suivi et participe à l'éducation thérapeutique (ETP) des patients vivants avec le VIH (PVVIH). Nous avons souhaité évaluer une dispensation délocalisée au sein d'un service de maladies infectieuses, en recueillant les motivations des patients et en faisant une évaluation économique. La dispensation hospitalière pouvant être une source de recettes non négligeable pour un établissement hospitalier. La pharmacie à usage intérieur (PUI) de notre établissement dispose d'une unité de vente au public ouverte en continu du lundi au vendredi de 8 h à 17 h et le samedi de 9 h à 16 h. Et d'une deuxième antenne délocalisée, ouverte du lundi au vendredi de 09 h à 17 h. Dans cette antenne, les préparatrices en pharmacie (PPH) ont réalisé de façon prospective une enquête sur le choix des patients du lieu de dispensation, en évaluant les motifs de ce choix. Un bilan financier de la rétrocession des antirétroviraux a été fait sur une année d'exercice. Intérêt pour les patients : sur une période de 10 jours, 124 patients consécutifs prenant leur traitement dans l'antenne délocalisée ont été interrogés, dont 88 (71 %) habitaient dans le département, 35 hors département (28 %) et une SDF. Parmi ces patients, 112 (90 %) avaient une dispensation hospitalière exclusive, et 12 (10 %) une dispensation mixte en ville et à l'hôpital. Parmi les patients habitant hors département, 28 (80 %) avaient une dispensation hospitalière exclusive. Les raisons évoquées pour la dispensation hospitalière exclusive étaient : l'habitude, 65 (52 %), discrétion/confidentialité, 51 (41 %), pratique, 45 (36 %), peu ou pas d'attente, 29 (23 %), pas besoin de commander, 6 (5 %) et autres, 13 (10 %). Intérêt pour l'établissement : Sur l'année 2019, 7951 titres de cessions ont été émis concernant 1223 patients venus au moins une fois et 855 patients venus au moins 3 fois. Les marges liées à la facturation de ces médicaments (22€ par ligne de traitement) ont généré une recette de 286 968€. À cette somme, s'ajoute la marge réalisée sur certains médicaments génériques de l'ordre de 250 000€ sur un an. Ce qui fait un total de plus de 500 000€ environ pour une année d'exercice. Dans cette file active d'environ 1400 PVVIH, plus de la moitié prennent leur traitement antirétroviral à la PUI et les recettes générées sont conséquentes. Si « l'habitude » est la première cause invoquée (52 %), le souci de « confidentialité/discrétion » est cité par 40 % des patients. Si la distance par rapport au lieu d'habitation constitue un frein à la dispensation hospitalière, le développement de l'ETP, l'existence de locaux adaptés, une plus grande disponibilité, en présence et en horaires d'ouverture peut attirer davantage de patients à la pharmacie hospitalière. Le gain pour la CPAM et pour les hôpitaux est réel et mérite une réflexion selon l'importance de la file active et le lieu de résidence des patients. [ABSTRACT FROM AUTHOR]

The article evaluates the human immunodeficiency virus (HIV)-1 p24 antigenemia and level of CD8+CD38+ T cells as surrogate markers of HIV-1 RNA viral load in HIV-1-infected patients in Dakar, Senegal. The authors compared a heat-denatured (HD) HIV p24 amplified enzyme-linked immunosorbent assay from Perkin-Elmer and CD8+CD38+ T-cell levels determined by flow cytometry. The result of the evaluation was discussed.

Reports on the comparison of CD4 cell counts in blood samples from HIV infected and uninfected subjects with the use of a research/clinical flow cytometer in volunteer subjects from Dakar, Senegal. Availability of parallel CD4 measurements; Avoidance of limitations with regard to sample throughput and workload; Advantage of microbead-based technology; Basis of the volumetric measurements of the sample fluid level.

The food grade bacterium Lactococcus iactis is a potential vehicle for protein delivery in the gastrointestinal tract. As a model, we constructed lactococcal strains producing antigens of infectious bursal disease virus (IBDV). IBDV infects chickens and causes depletion of B-lymphoid cells in the bursa of Fabricius and subsequent immunosuppression, morbidity, or acute mortality. The two major IBDV antigens, i.e., VP2 and VP3, that form the viral capsid were expressed and targeted to the cytoplasm, the cell wall, or the extracellular compartment of L. lactis. Whereas VP3 was successfully targeted to the three compartments by the use of relevant expression and export vectors, VP2 was recalcitrant to export, thus confirming the difficulty of translocating naturally nonsecreted proteins across the bacterial membrane. This defect could be partly overcome by fusing VP2 to a naturally secreted protein (the staphylococcal nuclease Nuc) that carried VP2 through the membrane. Lactococcal strains producing Nuc-VP2 and VP3 in various bacterial compartments were administered orally to chickens. The chickens did not develop any detectable immune response against VP2 and VP3 but did exhibit an immune response against Nuc when Nuc-VP2 was anchored to the cell wall of lactococci. [ABSTRACT FROM AUTHOR]

Designs an expression and export system that enables the targeting of a reporter protein Nuc, a staphylococcal nuclease, to specific locations in Lactococcus lactis. Improvement in protein export; Prevention of interaction of secreted Nuc with the cell wall; Effect of the nature of protein N terminus on protein release in a medium; Applications of protein targeting procedures in various lactic acid bacteria hosts.

The bond Grüneisen parameter of gallium arsenide's first shell was directly evaluated using temperature-dependent Extended X-ray Absorption Fine Structure (EXAFS) data. A quasi-harmonic approach based on the anharmonic contribution to parallel Mean Square Relative Displacement (MSRD) has led to a positive and weakly temperature-dependent linear bond Grüneisen parameter (GP) of GaAs in the entire region (14–300 K). For all temperatures, we report linear bond GPs greater than those retrieved with EXAFS using an anharmonic Einstein model. The comparison with volumic Grüneisen parameters given by diffraction or dilatometric techniques shows a significant difference which could be attributed to the different definitions used to connect frequency and bond length (or lattice parameter). These results are an evidence of the inadequacy of the quasi-harmonic model to deal with local properties using EXAFS. • GaAs' linear bond Grüneisen parameter (GP) is positive • GaAs' linear bond GP is weakly temperature dependent. • Linear bond GPs are higher than those given by anharmonic correlated Einstein model. • A marked difference is found between linear bond GPs given by EXAFS and XRD. • The quasi-harmonic model cannot deal with local properties using EXAFS. [ABSTRACT FROM AUTHOR]

Antimicrobial resistance (AMR) is a global public health threat. Quality data on AMR are needed to tackle the rise of multidrug-resistant clones. These data are rare in low-income countries, especially in sub-Saharan Africa. In this study, we investigated the rise of extended-spectrum β-lactamase–producing (ESBL) Enterobacteriaceae in Bangui, Central African Republic. We collected 278 fecal samples from 0–5-year-old children admitted to the Pediatric University Hospital Complex in Bangui from July to September 2021. Enterobacteriaceae were isolated and identified, and their susceptibility to 19 antibiotics was tested. We recovered one and two Enterobacteriaceae species from 208 and 29 samples, respectively. One clone of each species from each sample was further characterized, for a total of 266 isolates. Escherichia coli predominated, followed by Klebsiella. AMR was frequent, with 98.5% (262/266) of the isolates resistant to at least one antibiotic. Additionally, 89.5% (238/266) of the isolates were multidrug resistant, with resistance being frequent against all tested antibiotics except carbapenems and tigecycline, for which no resistance was found. Importantly, 71.2% (198/278) of the children carried at least one ESBL species, and 85.3% (227/266) of the isolates displayed this phenotype. This study confirms the rise of ESBL Enterobacteriaceae in Bangui and stresses the need for action to preserve the efficacy of antibiotics, as crucial for the treatment of bacterial infections. [ABSTRACT FROM AUTHOR]

In the context of food transition, the agrifood sector has experienced increasingly strong demand for horticultural products. Fresh fruits and vegetables are mainly vehicles of microorganisms, including pathogens that cause human infections. Food safety and compliance with health standards in the fruits and vegetable value chain are significant concerns and multiple challenges, given the prevalence of foodborne pathologies in Southern countries, particularly in Senegal. This study aimed to describe the bacterial community and assess the microbiological quality of a range of fruits and vegetables sold on street stalls and open-air markets in Dakar, the capital city of Senegal. Samples purchased in seven sites were analyzed to isolate Escherichia coli (E. coli), Salmonella spp. and Vibrio spp. Some primary samples with a positive microbiological culture were subjected to DNA extraction and subsequent metagenomic analysis. A total of 240 fresh fruit and vegetable samples were collected, including lettuce (n = 40), tomatoes (n = 40), mango slices (n = 40), onion slices (n = 40), mint leaves (n = 40), strawberries and grapes (each n = 20). Of these samples, 50.83% (122/240) and 60.41% (145/240) were contaminated with E. coli and Vibrio spp., respectively, while Salmonella was not isolated in any product. E. coli and Vibrio spp. contamination levels, 1.3 103 to 6 106 Colonies Forming Units per gram of sample (CFU/g) and 4.55 102 to 8.73 106 CFU/g, respectively, were significantly above the thresholds acceptable for human consumption. The most contaminated samples were lettuce, with a prevalence of 98% (39/40) for E. coli and Vibrio spp. followed by mint leaves with 100% (40/40) and 93% (37/40) of the samples containing E. coli and Vibrio spp. respectively. Out of 46 samples sequenced, the metagenomic analysis revealed high contamination rates for E. coli, Vibrio spp. and Salmonella spp., with 100%, 67.39% and 93.47% of prevalence, respectively. On the other hand, the alpha diversity analysis shows high bacterial diversity in lettuce and mint leaf samples, while the beta diversity analysis highlighted the presence of two major clusters. Our results stress the need for a surveillance system that extends this investigation to a national scale while increasing the number of sampling sites and products analyzed. [ABSTRACT FROM AUTHOR]

Background: Acinetobacter baumannii is a gram-negative, opportunistic pathogen, that is responsible for a wide variety of infections and is a significant cause of hospital-acquired infections. A. baumannii is listed by the World Health Organization (WHO) as a critical priority pathogen because of its high level of antibiotic resistance and the urgent need for alternative treatment solutions. To address this challenge, bacteriophages have been used to combat bacterial infections for more than a century, and phage research has regained interest in recent years due to antimicrobial resistance (AMR). However, although the vast majority of deaths from the AMR crisis will occur in developing countries in Africa and Asia, few phages' studies have been conducted in these regions. In this study, we present a comprehensive characterization of the bacteriophages vAbBal23 and vAbAbd25, actives against extremely drug-resistant (XDR) A. baumannii. Methods: Phages were isolated from environmental wastewaters in Dakar, Senegal. The host-range, thermal and pH stabilities, infection kinetics, one step growth assay, antibiofilm activity assay, sequencing, and genomic analysis, were performed to characterize the isolated phages. Results: Comparative genomic and phylogenetic analyses revealed that vAbBal23 and vAbAbd25 belong to the Caudoviricetes class, Autographiviridae family and Friunavirus genus. Both phages demonstrated activity against strains with capsular type KL230. They were stable over a wide pH range (pH 3 to 9) and at temperatures ranging from 25 °C to 40 °C. Additionally, the phages exhibited notable activity against both planktonic and biofilm cells of targeted extremely drug resistant A. baumannii. The results presented here indicate the lytic nature of vAbBal23 and vAbAbd25. This is further supported by the absence of genes encoding toxins, resistance genes and bacterial virulence factors, highlighting their potential for future phage applications. Conclusion: Phages vAbBal23 and vAbAbd25 are promising biological agents that can infect A. baumannii, making them suitable candidates for use in phage therapies. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the interactions between wheat plant (spikelets and straws), a strain of mycotoxigenic pathogen Fusarium graminearum and commercial biocontrol agents (BCAs). The ability of BCAs to colonize plant tissue and inhibit the pathogen or its toxin production was observed throughout two phases of the life cycle of pathogens in natural conditions (colonization and survival). All evaluated BCAs showed effective reduction capacities of pathogenic traits. During establishment and the expansion stage, BCAs provoked an external growth reduction of F. graminearum (77–93% over the whole kinetic studied) and mycotoxin production (98–100% over the whole kinetic studied). Internal growth of pathogen was assessed with digital droplet polymerase chain reaction (ddPCR) and showed a very strong reduction in the colonization of the internal tissues of the spikelet due to the presence of BCAs (98% on average). During the survival stage, BCAs prevented the formation of conservation perithecia of the pathogen on wheat straw (between 88 and 98% of perithecia number reduction) and showed contrasting actions on the ascospores they contain, or perithecia production (−95% on average) during survival form. The mechanisms involved in these different interactions between F. graminearum and BCAs on plant matrices at different stages of the pathogen's life cycle were based on a reduction of toxins, nutritional and/or spatial competition, or production of anti-microbial compounds. [ABSTRACT FROM AUTHOR]

ABSTRACT There is a growing recognition of the importance of transboundary shared natural resources. However, with limited resources, international policymakers need to be able to prioritize regions before allocating resources and addressing transboundary problems. River basins are perhaps the most natural transboundary division and, as such, provide an ecological framework for environmental assessments. The health of watersheds that are divided by political boundaries are at particular risk due to differential land management practices within each watershed. In Africa, more than any other continent, over 60% of the geographical area is a transboundary watershed. In this article, a comparative study of the five major basins in Africa—the Congo, Chad, Nile, Niger, and Zambezi—has been carried out using consistent geospatial data sets at 1-km resolution. Population, land cover type, and protected areas were used to assess the current status, characteristic differences, and impending pressure on river basin resources for each watershed. In addition, a focused study within the Nile River basin is used to compare the particular differences between countries. [ABSTRACT FROM AUTHOR]

An amendment to this paper has been published and can be accessed via the original article. [ABSTRACT FROM AUTHOR]

Background Genome-wide association studies have identified several nonfunctional tag single-nucleotide polymorphisms (SNPs) associated with severe malaria. We hypothesized that causal SNPs could play a significant role in severe malaria by altering promoter or enhancer activity. Here, we sought to identify such regulatory SNPs. Methods SNPs in linkage disequilibrium with tagSNPs associated with severe malaria were identified and were further annotated using FUMA. Then, SNPs were prioritized using the integrative weighted scoring method to identify regulatory ones. Gene reporter assays were performed to assess the regulatory effect of a region containing candidates. The association between SNPs and severe malaria was assessed using logistic regression models in a Senegalese cohort. Results Among 418 SNPs, the best candidates were rs116525449 and rs79644959, which were in full disequilibrium between them, and located within the ARL14 promoter. Our gene reporter assay results revealed that the region containing the SNPs exhibited cell-specific promoter or enhancer activity, while the SNPs influenced promoter activity. We detected an association between severe malaria and those 2 SNPs using the overdominance model and we replicated the association of severe malaria with the tagSNP rs116423146. Conclusions We suggest that these SNPs regulate ARL14 expression in immune cells and the presentation of antigens to T lymphocytes, thus influencing severe malaria development. [ABSTRACT FROM AUTHOR]

Evaluations of treatment efficacy in Duchenne muscular dystrophy (DMD), a rare genetic disease that results in progressive muscle wasting, require an understanding of the 'meaningfulness' of changes in functional measures. We estimated the minimal detectable change (MDC) for selected motor function measures in ambulatory DMD, i.e., the minimal degree of measured change needed to be confident that true underlying change has occurred rather than transient variation or measurement error. MDC estimates were compared across multiple data sources, representing >1000 DMD patients in clinical trials and real-world clinical practice settings. Included patients were ambulatory, aged ≥4 to <18 years and receiving steroids. Minimal clinically important differences (MCIDs) for worsening were also estimated. Estimated MDC thresholds for >80% confidence in true change were 2.8 units for the North Star Ambulatory Assessment (NSAA) total score, 1.3 seconds for the 4-stair climb (4SC) completion time, 0.36 stairs/second for 4SC velocity and 36.3 meters for the 6-minute walk distance (6MWD). MDC estimates were similar across clinical trial and real-world data sources, and tended to be slightly larger than MCIDs for these measures. The identified thresholds can be used to inform endpoint definitions, or as benchmarks for monitoring individual changes in motor function in ambulatory DMD. [ABSTRACT FROM AUTHOR]

Listeriosis is a foodborne infection caused by Listeria monocytogenes. Three main forms of listeriosis are well characterised, but little is known about L monocytogenes -associated spontaneous bacterial peritonitis. We used data from the French national surveillance of listeriosis to perform a nationwide retrospective study. All patients with L monocytogenes isolated by culture from a peritoneal fluid sample in France between April 1, 1993, and Dec 31, 2022, were included. Individuals for whom bacterial peritonitis was not confirmed and those who also had another type of invasive listeriosis were excluded. A standardised checklist was used to collect demographic, clinical, and biological data as well as antibiotic treatment and follow-up data. The primary outcome was to determine the characteristics of L monocytogenes -associated spontaneous bacterial peritonitis. We did descriptive analyses and assessed risk factors for 1-month mortality using an exploratory multivariable Cox model analysis. Among the 8768 L monocytogenes cases reported, 208 (2%) were patients with L monocytogenes -associated spontaneous bacterial peritonitis. Mean age was 65 years (SD 13), 50 (24%) of 208 patients were female, and 158 (76%) were male (no data on race or ethnicity were available). 200 (98%) of 205 patients with L monocytogenes -associated spontaneous bacterial peritonitis with available data had immunosuppressive comorbidities, including cirrhosis (148 [74%] of 201 with available data), ongoing alcoholism (58 [62%] of 94), and ongoing neoplasia (60 [31%] of 195). Causes of ascites included cirrhosis (146 [70%] of 208), ongoing neoplasia (26 [13%]), end-stage heart failure (13 [6%]), and peritoneal dialysis (11 [5%]). Among those with available data, presentation was pauci-symptomatic and non-specific; only 67 (50%) of 135 patients presented with fever, 49 (37%) of 132 with abdominal pain, and 27 (21%) of 129 with diarrhoea. 61 (29%) of 208 patients were dead at 1 month, 92 (44%) were dead at 3 months, and 109 (52%) were dead at 6 months after diagnosis. Ongoing neoplasia (hazard ratio 2·42 [95% CI 1·05–5·56]; p=0·039), septic shock (8·03 [2·66–24·02]; p=0·0021), and high blood leukocyte count (1·05 [1·00–1·09]; p=0·045) were independently associated with 1-month mortality. Despite the non-specific and mild presentation of L monocytogenes -associated spontaneous bacterial peritonitis, the outcome is poor and similar to that of neurolisteriosis, and so identification of L monocytogenes in ascitic fluid samples requires urgent parenteral amoxicillin-based treatment to avoid a fatal outcome. Institut Pasteur, Inserm, and French Public Health Agency. For the French translation of the abstract see Supplementary Materials section. [ABSTRACT FROM AUTHOR]