High unhealthy food and beverage consumption is associated with poor diet quality among 12–35-month-olds in Guédiawaye Department, Senegal

BackgroundHigh consumption of unhealthy foods and beverages (UFB) during early childhood is cause for concern, with growing evidence from low- and middle-income countries finding associations with poor diet quality and malnutrition. Research from sub-Saharan Africa remains limited, with no studies quantifying the contribution of UFB to total energy intakes among young children or exploring the relationship between such intakes and diet quality or anthropometric outcomes.ObjectivesAssess UFB consumption patterns and their contribution to total energy intake from non-breastmilk foods/beverages (TEI-NBF), assess the association between high UFB consumption and dietary/nutrition outcomes, and explore drivers of unhealthy food choice among young children in Guédiawaye Department, Senegal.MethodsWe conducted a cross-sectional study of a representative sample of 724 primary caregivers and their 12–35.9-month-old children. The study included a questionnaire, a quantitative four-pass 24-h dietary recall, and anthropometric measurements. The contribution of UFB to TEI-NBF was calculated and terciles generated. Logistic and linear models were used to compare outcomes of high versus low UFB consumption terciles.ResultsUFB contributed on average 22.2% of TEI-NBF, averaging 5.9% for the lowest tercile and 39.9% for the highest. Diets of high UFB consumers, as compared to low, were significantly less dense in protein, fiber, and seven of the 11 micronutrients assessed and significantly denser in total fat, saturated fat, and total sugar. No associations were found with anthropometric outcomes. High UFB consumers were older and more likely to be living in food insecurity. The most common drivers of commercial UFB consumption were related to child preference, the use of these products as behavior management tools, treats, or gifts, and the sharing of these products by someone else eating them.ConclusionHigh UFB consumption is associated with poor diet quality among 12–35-month-olds in Guédiawaye Department, Senegal. Addressing high UFB consumption during this critical developmental period should be prioritized in young child nutrition research, programming, and policy development

Implementing a Care Pathway for small and nutritionally at-risk infants under six months of age: A multi-country stakeholder consultation

Nutritional vulnerability under the age of 6 months is prevalent in low- and middle-income countries with 20.1% infants underweight, 21.3% wasted and 17.6% stunted in a recent review. A novel Care Pathway for improved management of small and nutritionally at-risk infants under 6 months and their mothers (MAMI) has recently been developed to provide outpatient care at large coverage. We aimed to investigate stakeholders' views on the feasibility of its implementation and to identify barriers and enablers. This was an early stage formative mixed-methods study: an online survey plus in-depth interviews with country-level stakeholders in nutrition and child health from different geographical regions and stakeholder groups. 189 stakeholders from 42 countries responded to the online survey and 14 remote interviews were conducted. Participants expressed an urgent need for improved detection and care for small and nutritionally at-risk infants under 6 months. Whilst they considered the MAMI Care Pathway feasible and relevant, they noted it was largely unknown in their country. The most mentioned implementation barriers were: community-specific needs and health care seeking barriers, health workers' lack of competence in breastfeeding counselling and the absence of a validated anthropometric screening method. Possible enablers for its implementation were: patients' preference for outpatient care, integrating the MAMI care pathway into existing maternal and child health programmes and the possibility of a local pilot project. Adaptation to the local context was considered crucial in further scale-up

Antimicrobial peptides resistance mechanism mediated by an ABC transporter coupled to a two-component system in Streptococcus pneumoniae

La résistance aux antibiotiques est un problème majeur de santé publique qui affecte de nombreux pathogènes bactériens. Pour ralentir ce phénomène, des peptides antimicrobiens (PAMs), naturellement synthétisés et impliqués dans la défense immunitaire de différents organismes, est une approche thérapeutique prometteuse. Cependant, les bactéries présentent de nombreux mécanismes capables de contrecarrer l’action de ces peptides. L’un des mécanisme de résistance les plus importants implique une étroite collaboration entre un transporteur ABC et un système de régulation à deux composants (TCS). Pour comprendre le mécanisme de résistance aux PAMs chez Streptococcus pneumoniae, un important pathogène humain, nous avons identifié le TCS associé au transporteur ABC de PAMs. Le TCS01 en collaboration avec un transporteur ABC de type BceAB détecte et induit la résistance à des PAMs structurellement différents mais ciblant l’undécaprényl-pyrophosphate ou le lipide II, essentiels à la biosynthèse du peptidoglycane. Bien que les gènes codant le TCS01 et le transporteur BceAB ne soient pas adjacents, leurs délétions sensibilisent de la même manière S. pneumoniae aux mêmes PAMs. Nous avons montré par des expériences de fluorescence et de qPCR que le TCS01 régulait l’expression du transporteur BceAB. Afin de caractériser le mécansime moléculaire du transporteur BceAB, nous l’avons surexprimé et purifié à partir d’Escherichia coli. Après la reconstitution en liposomes, le transporteur présente des activités ATPase et GTPase significatives qui sont stimulées par les PAMs substrats du système de résistance.Antibiotic resistance is a growing threat to public health affecting many bacterial pathogens. To slow this phenomenon, antimicrobial peptides (AMPs), naturally synthesized and involved in immune defence of several organisms, are a promising therapeutic approach. However, bacteria present plenty mechanisms to thwart thes peptides action. One of the most important resistance mechanisms involves a close collaboration between an ABC transporter and a two-component regulatory system (TCS). To understand the mechanism of resistance to AMPs in Streptococcus pneumoniae, an important human pathogen, we identified the TCS associated with the ABC transporter of AMPs. TCS01 in collaboration with a BceAB-like ABC transporter detect and induc resistance to structurally-unrelated antimicrobial peptides but targeting undecaprenyl-pyrophosphate or lipid II, which are essential for peptidoglycan biosynthesis. Although the genes encoding TCS01 and the BceAB transporter are not located in the same gene cluster, the disruption of either of them equally sensitized S. pneumoniae to the same AMPs. We have shown by fluorescence and qPCR experiments that TCS01 regulates the expression of the BceAB transporter. To characterize the molecular mechanism of the BceAB transporter, we overexpressed and purified it from Escherichia coli. After reconstitution in liposomes, the transporter exhibits subtantial ATPase and GTPase activities which are stimulated by the AMPs substrates of the resistance system

Etude du mécanisme de résistance aux peptides antimicrobiens médié par un transporteur ABC couplé à un système de régulation à deux composants chez Streptococcus pneumoniae

Antibiotic resistance is a growing threat to public health affecting many bacterial pathogens. To slow this phenomenon, antimicrobial peptides (AMPs), naturally synthesized and involved in immune defence of several organisms, are a promising therapeutic approach. However, bacteria present plenty mechanisms to thwart thes peptides action. One of the most important resistance mechanisms involves a close collaboration between an ABC transporter and a two-component regulatory system (TCS). To understand the mechanism of resistance to AMPs in Streptococcus pneumoniae, an important human pathogen, we identified the TCS associated with the ABC transporter of AMPs. TCS01 in collaboration with a BceAB-like ABC transporter detect and induc resistance to structurally-unrelated antimicrobial peptides but targeting undecaprenyl-pyrophosphate or lipid II, which are essential for peptidoglycan biosynthesis. Although the genes encoding TCS01 and the BceAB transporter are not located in the same gene cluster, the disruption of either of them equally sensitized S. pneumoniae to the same AMPs. We have shown by fluorescence and qPCR experiments that TCS01 regulates the expression of the BceAB transporter. To characterize the molecular mechanism of the BceAB transporter, we overexpressed and purified it from Escherichia coli. After reconstitution in liposomes, the transporter exhibits subtantial ATPase and GTPase activities which are stimulated by the AMPs substrates of the resistance system.La résistance aux antibiotiques est un problème majeur de santé publique qui affecte de nombreux pathogènes bactériens. Pour ralentir ce phénomène, des peptides antimicrobiens (PAMs), naturellement synthétisés et impliqués dans la défense immunitaire de différents organismes, est une approche thérapeutique prometteuse. Cependant, les bactéries présentent de nombreux mécanismes capables de contrecarrer l’action de ces peptides. L’un des mécanisme de résistance les plus importants implique une étroite collaboration entre un transporteur ABC et un système de régulation à deux composants (TCS). Pour comprendre le mécanisme de résistance aux PAMs chez Streptococcus pneumoniae, un important pathogène humain, nous avons identifié le TCS associé au transporteur ABC de PAMs. Le TCS01 en collaboration avec un transporteur ABC de type BceAB détecte et induit la résistance à des PAMs structurellement différents mais ciblant l’undécaprényl-pyrophosphate ou le lipide II, essentiels à la biosynthèse du peptidoglycane. Bien que les gènes codant le TCS01 et le transporteur BceAB ne soient pas adjacents, leurs délétions sensibilisent de la même manière S. pneumoniae aux mêmes PAMs. Nous avons montré par des expériences de fluorescence et de qPCR que le TCS01 régulait l’expression du transporteur BceAB. Afin de caractériser le mécansime moléculaire du transporteur BceAB, nous l’avons surexprimé et purifié à partir d’Escherichia coli. Après la reconstitution en liposomes, le transporteur présente des activités ATPase et GTPase significatives qui sont stimulées par les PAMs substrats du système de résistance

Etude du mécanisme de résistance aux peptides antimicrobiens médié par un transporteur ABC couplé à un système de régulation à deux composants chez Streptococcus pneumoniae

Antibiotic resistance is a growing threat to public health affecting many bacterial pathogens. To slow this phenomenon, antimicrobial peptides (AMPs), naturally synthesized and involved in immune defence of several organisms, are a promising therapeutic approach. However, bacteria present plenty mechanisms to thwart thes peptides action. One of the most important resistance mechanisms involves a close collaboration between an ABC transporter and a two-component regulatory system (TCS). To understand the mechanism of resistance to AMPs in Streptococcus pneumoniae, an important human pathogen, we identified the TCS associated with the ABC transporter of AMPs. TCS01 in collaboration with a BceAB-like ABC transporter detect and induc resistance to structurally-unrelated antimicrobial peptides but targeting undecaprenyl-pyrophosphate or lipid II, which are essential for peptidoglycan biosynthesis. Although the genes encoding TCS01 and the BceAB transporter are not located in the same gene cluster, the disruption of either of them equally sensitized S. pneumoniae to the same AMPs. We have shown by fluorescence and qPCR experiments that TCS01 regulates the expression of the BceAB transporter. To characterize the molecular mechanism of the BceAB transporter, we overexpressed and purified it from Escherichia coli. After reconstitution in liposomes, the transporter exhibits subtantial ATPase and GTPase activities which are stimulated by the AMPs substrates of the resistance system.La résistance aux antibiotiques est un problème majeur de santé publique qui affecte de nombreux pathogènes bactériens. Pour ralentir ce phénomène, des peptides antimicrobiens (PAMs), naturellement synthétisés et impliqués dans la défense immunitaire de différents organismes, est une approche thérapeutique prometteuse. Cependant, les bactéries présentent de nombreux mécanismes capables de contrecarrer l’action de ces peptides. L’un des mécanisme de résistance les plus importants implique une étroite collaboration entre un transporteur ABC et un système de régulation à deux composants (TCS). Pour comprendre le mécanisme de résistance aux PAMs chez Streptococcus pneumoniae, un important pathogène humain, nous avons identifié le TCS associé au transporteur ABC de PAMs. Le TCS01 en collaboration avec un transporteur ABC de type BceAB détecte et induit la résistance à des PAMs structurellement différents mais ciblant l’undécaprényl-pyrophosphate ou le lipide II, essentiels à la biosynthèse du peptidoglycane. Bien que les gènes codant le TCS01 et le transporteur BceAB ne soient pas adjacents, leurs délétions sensibilisent de la même manière S. pneumoniae aux mêmes PAMs. Nous avons montré par des expériences de fluorescence et de qPCR que le TCS01 régulait l’expression du transporteur BceAB. Afin de caractériser le mécansime moléculaire du transporteur BceAB, nous l’avons surexprimé et purifié à partir d’Escherichia coli. Après la reconstitution en liposomes, le transporteur présente des activités ATPase et GTPase significatives qui sont stimulées par les PAMs substrats du système de résistance

Functional Overexpression of Membrane Proteins in E. coli: The Good, the Bad, and the Ugly

International audienceOverexpression of properly folded membrane proteins is a mandatory step for their functional and structural characterization. One of the most used expression systems for the production of proteins is Escherichia coli. Many advantageous strains combined with T7 expression systems have been developed over the years. Recently, we showed that the choice of the strain is critical for the functionality of membrane proteins, even when the proteins are successfully incorporated in the membrane (Mathieu et al. Sci Rep. 2019; 9(1):2654). Notably, the amount and/or activity of the T7-RNA polymerase, which drives the transcription of the genes of interest, may indirectly affect the folding and functionality of overexpressed membrane proteins. Moreover, we reported a general trend in which mild detergents mainly extract the population of active membrane proteins, whereas a harsher detergent like Fos-choline 12 could solubilize them irrespectively of their functionality. Based on these observations, we provide some guidelines to optimize the quality of membrane proteins overexpressed in E. col

Effect of Plant Growth Promoting Rhizobacteria (PGPR) and Arbuscular Mycorrhizal Fungi (AMF) on Salt Stress Tolerance of Casuarina obesa (Miq.)

International audienceSalinity is one of the main abiotic stresses limiting plant growth and development. However, the use of salt-tolerant plants combined with beneficial soil microorganisms could improve the effectiveness of biological methods for saline soil recovery. The aim of this study is to identify the Casuarina obesa/ Arbuscular Mycorrhizal fungi (AMF)/Plant Growth Promoting Rhizobacteria (PGPR) association that could be used in salt-land rehabilitation programs. Thus, the plants were grown under greenhouse on sandy soil, inoculated either with PGPR (Pantoea agglomerans and Bacillus sp.), or with AMF (Rhizophagus fasciculatus and Rhizophagus aggregatum) or co inoculated with PGPR and AMF and watered with a saline solution (0, 150, and 300 mM). After 4 months of cultivation, the plants were harvested and the results obtained showed that inoculation improves the survival rate, height and biomass of the plants compared to the control plants. The results also showed that inoculation increases the total amount of chlorophyll and the accumulation of plant proline at all levels of salt concentration. However, P. agglomerans and Bacillus sp. strains alone or in combination with R. fasciculatus increased plant growth. This study showed that these strains of PGPR, whether or not associated with AMF, could be biological tools to improve C. obesa performance under saline stress conditions

Possible influence of Plasmodium/Trypanosoma co-infections on the vectorial capacity of Anopheles mosquitoes

International audienceOBJECTIVE:In tropical Africa, trypanosomiasis is present in endemic areas with many other diseases including malaria. Because malaria vectors become more anthropo-zoophilic under the current insecticide pressure, they may be exposed to trypanosome parasites. By collecting mosquitoes in six study sites with distinct malaria infection prevalence and blood sample from cattle, we tried to assess the influence of malaria-trypanosomiasis co-endemicity on the vectorial capacity of Anopheles.RESULTS:Overall, all animal infections were due to Trypanosoma vivax (infection rates from 2.6 to 10.5%) in villages where the lowest Plasmodium prevalence were observed at the beginning of the study. An. gambiae s.l. displayed trophic preferences for human-animal hosts. Over 84 mosquitoes, only one was infected by Plasmodium falciparum (infection rate: 4.5%) in a site that displayed the highest prevalence at the beginning of the study. Thus, Anopheles could be exposed to Trypanosoma when they feed on infected animals. No Plasmodium infection was observed in the Trypanosoma-infected animals sites. This can be due to an interaction between both parasites as observed in mice and highlights the need of further studies considering Trypanosoma/Plasmodium mixed infections to better characterize the role of these infections in the dynamic of malaria transmission and the mechanisms involved

Identification of a two-component regulatory system involved in antimicrobial peptide resistance in Streptococcus pneumoniae

International audienceTwo-component regulatory systems (TCS) are among the most widespread mechanisms that bacteria use to sense and respond to environmental changes. In the human pathogen Streptococcus pneumoniae , a total of 13 TCS have been identified and many of them have been linked to pathogenicity. Notably, TCS01 strongly contributes to pneumococcal virulence in several infection models. However, it remains one of the least studied TCS in pneumococci and its functional role is still unclear. In this study, we demonstrate that TCS01 cooperates with a BceAB-type ABC transporter to sense and induce resistance to structurally-unrelated antimicrobial peptides of bacterial origin that all target undecaprenyl-pyrophosphate or lipid II, which are essential precursors of cell wall biosynthesis. Even though tcs01 and bceAB genes do not locate in the same gene cluster, disruption of either of them equally sensitized the bacterium to the same set of antimicrobial peptides. We show that the key function of TCS01 is to upregulate the expression of the transporter, while the latter appears the main actor in resistance. Electrophoretic mobility shift assays further demonstrated that the response regulator of TCS01 binds to the promoter region of the bceAB genes, implying a direct control of these genes. The BceAB transporter was overexpressed and purified from E . coli . After reconstitution in liposomes, it displayed substantial ATPase and GTPase activities that were stimulated by antimicrobial peptides to which it confers resistance to, revealing new functional features of a BceAB-type transporter. Altogether, this inducible defense mechanism likely contributes to the survival of the opportunistic microorganism in the human host, in which competition among commensal microorganisms is a key determinant for effective host colonization and invasive path