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The nature and frequency of food and beverage marketing on Kenyan national television: a mixed-method analysis of food advertisements, parent and children’s perspectives
No full textInternational audienceBackground Exposure of children and adolescents to unhealthy food through marketing and advertising on television (TV) is associated with increased consumption of unhealthy foods and subsequently, overweight/obesity and diet-related non-communicable diseases (NCDs). This study assessed the nature, frequency, and exposure of children to food and beverage advertisements on TV and the perspectives of children/adolescents and parents on food marketing on TV. Methods Mixed methods, nationally representative study, guided by the International Network for Food and Obesity/NCDs Research, Monitoring and Action Support (INFORMAS) protocol for monitoring food promotion. This entailed simultaneous recording of the three most popular national TV channels in Kenya for eight randomly selected days, 18 h/day, over a 3-month period in 2021-2022. The NOVA classification was used to categorize food based on level of processing. Differences in advertisements by food groups, recording days (weekday/weekend) and seasons (holiday/non-holiday) were assessed. Focus group discussions (n = 14) and in-depth interviews (n = 29) were conducted with school children/adolescents (~ 9-18 years) and parents respectively in three counties, to explore their experiences and perspectives of food advertisements. Data were coded in NVIVO and analyzed thematically. ResultsOf the 3700 advertisements recorded, about a third (36%, n = 1316) comprised of food and beverages; 94.7% (n = 1213) were ultra-processed foods (UPFs), with a mean rate of 2.8 ads/channel per hour, the majority (95.9%, n = 557) of which were broadcast during peak hours. Some of the children interviewed vividly remembered some of the advertised food brands, mainly those related to UPFs. Most parents acknowledged that their children paid attention to food advertisements and sometimes requested and expressed preference for the advertised foods or brands. Parents generally considered food advertising to be safe, with no concerns about unhealthy food exposure to children.</div
Checklist and diversity of tick fauna associated with domestic animals in Cambodia
No full textInternational audienceThe tick fauna in Cambodia is poorly documented, with limited information on the diversity and distribution of tick species. This study aimed to address this knowledge gap by investigating tick species collected from various hosts, and across different habitats and regions of the country. Tick sampling was conducted in urban areas, rural villages, farms, and forest fringes, with additional samples obtained from a wildlife rescue center, caves, and swiftlet nests. Ticks were collected directly from hosts, as well as on vegetation through flagging methods. Tick species were identified morphologically, and selected specimens were subjected to molecular identification using the cox1 gene. A total of 853 vertebrate hosts representing 13 different animals, including five wildlife, were inspected: buffalo, cats, cattle, chickens, dogs, ducks, goats, goose, pigs, pigeons, pangolins, pythons, and wild pigs. From this first nationwide tick collection, a total of 7,461 ticks were collected, comprising six genera and 14 species of ticks, including seven newly identified species such as Carios batuensis, Dermacentor steini, Dermacentor filippovae, Haemaphysalis canestrinii, Haemaphysalis formosensis, Haemaphysalis hystricis, and Haemaphysalis wellingtoni. Rhipicephalus microplus and Rhipicephalus linnaei were the most predominant tick species collected from cattle and dogs, respectively, whereas no ticks were found on buffaloes, chickens, ducks, goose, pigs or pigeons. Results showed that ticks are widely distributed throughout Cambodia, with particularly rich diversity observed in forest fringes habitats. This study also allowed the number of tick species identified in the country with seven additional species, bringing the total to 26
Développement et fabrication par impression 3D d’un système microfluidique ouvrable et instrumenté avec un capteur de bioimpédance pour la culture in vitro de tissus biologiques 3D
No full textCell culture is an indispensable tool in biology. It has led to a better understanding of fundamental biological mechanisms and has been at the heart of progress in biology and medicine. However, conventional culture models (static in vitro 2D and 3D and in vivo) have limitations such as simplified tissue representation and interspecies incompatibility. Microfluidic systems better reproduce the dynamic environment of biological tissues by incorporating features such as interstitial flow. In this way, they facilitate the discovery of new drugs and the development of personalised medicine, in line with the 3Rs rule. Assessing the efficacy of these therapeutic candidates is generally based on measuring post-treatment cell viability. However, these tests are destructive and endpoint, providing no dynamic information about the tissues being studied. Bioimpedance sensors, based on the low-frequency measurement of the opposition of the cell membrane to the passage of an alternating current,provide a non-destructive, real-time measurement of cell density and therefore viability. In this context, the first objective of my thesis was to develop an openable and parallelised microfluidic system integrating a solid 3D tissue model. We defined its geometry by numerical modelling, taking into account the in vivo data available in the literature. We then developed a manufacturing protocol based on 3D printing. We studied its culture capacity by carrying out dynamic cultures of pancreatic cancer cells in 2D monolayers and 3D cultures. The second objective of my thesis was to integrate and characterise an impedance biosensor in the chambers of the microfluidic system. We defined its geometry using numerical modelling and studied its sensitivity. It was manufactured using photolithography and lift-off. Its characterisation enabled us to quantify the impact of geometry and temperature on the electrical measurement. Initial preliminary results validated that the instrumented microsystem could be used to monitor changes in cell density in dynamic 2D and 3D cultures of pancreatic cancer cells.La culture cellulaire constitue un outil indispensable en biologie. Elle a permis de mieux comprendre des mécanismes biologiques fondamentaux et a été au coeur de progrès en biologie et médecine. Cependant, les modèles de culture classiques (statiques in vitro 2D et 3D et in vivo) présentent des limitations telles que la représentation simplifiée du tissu ou l’incompatibilité inter-espèces. Les systèmes microfluidiques reproduisent mieux l'environnement dynamique d’un tissu biologique en intégrant des caractéristiques comme le flux interstitiel. Ils favorisent ainsi la découverte de nouveaux médicaments et le développement de la médecine personnalisée, tout en s’inscrivant dans la lignée de la règle des 3R. L’évaluation de l’efficacité de ces candidats thérapeutiques repose généralement sur la mesure de la viabilité cellulaire post traitement. Ces tests sont cependant destructifs et réalisés en point final, ne fournissant pas d’information dynamique sur les tissus étudiés. Les capteurs de bioimpédance, basés sur la mesure à basse fréquence de l’opposition de la membrane des cellules au passage du courant alternatif, permettent une mesure en temps réel, non destructive,de la densité cellulaire, et donc de la viabilité. Dans ce contexte, le premier objectif de ma thèse a été le développement d'un système microfluidique ouvrable et parallélisé intégrant un modèle tissulaire 3D solide. Nous avons défini sa géométrie par modélisation numérique en prenant en compte les données in vivo disponible dans la littérature. Nous avons ensuite développé un protocole de fabrication reposant sur l’impression 3D. Nous avons étudié sa capacité de culture en réalisant des cultures dynamiques de cellules cancéreuses pancréatiques d’une part en monocouche 2D et d’autre part en culture 3D. Le deuxième objectif de ma thèse consistait à intégrer et caractériser un biocapteur d’impédance dans les chambres du système microfluidique. Nous avons défini sa géométrie par modélisation numérique en étudiant sa sensibilité. Sa fabrication a été réalisée par photolithographie et lift-off. Sa caractérisation a permis de quantifier l’impact de la géométrie et de la température sur la mesure électrique. Des premiers résultats préliminaires ont permis de valider que le microsystème instrumenté permettait le suivi de l’évolution de la densité cellulaire au sein de cultures 2D et 3D dynamique de cellules pancréatiques cancéreuses
Genetics of prelingual isolated deafness and Usher syndrome in the Maghreb and Jordan: Harnessing the potential of homozygosity
No full textInternational audienceThe molecular genetic diagnosis of prelingual sensorineural hearing impairment (HI) is essential for genetic counseling and patient management. Effective diagnosis requires a knowledge of the genetic architecture of HI, which is often lacking. We established a cohort of 450 unrelated patients with familial (at least two affected relatives) severe-to-profound bilateral prelingual HI in five countries with high consanguinity rates: Tunisia, Jordan, Algeria, Morocco, and Mauritania (the TJAMM cohort). Recessive and dominant inheritance were observed in 92% and 8% of cases, respectively; 14% were syndromic. Genome analysis detected 211 different mutations (36% not reported before) in 49 deafness genes, and fully resolved 90% of cases of autosomal recessive isolated deafness (DFNB forms), 89% of the mutations being homozygous. The deafness genes involved were similar in different countries, but their mutations, except a few in GJB2 and LRTOMT , differed considerably, suggesting an overrepresentation of private mutations. Biallelic missense mutations in MYO7A , CDH23 , PCDH15 , USH1C cause either DFNB forms or Usher syndrome type 1 (USH1) ( USH1/DFNB genes). Such mutations were overrepresented (13% of patients), highlighting the importance of distinguishing between these two mutation classes. We hypothesized that current difficulties might stem from the misclassification of certain mutations. By studying the 65 USH1/DFNB missense mutations reported to cause DFNB in the homozygous state, we identified some that, when associated with a loss-of-function mutation, resulted in USH1, a characteristic pattern of some recessive hypomorphic mutations. This reappraised classification of USH1/DFNB mutations has the potential to improve molecular diagnosis and patient management significantly
Cosolvent Effects Question the Role of Water in Native Chemical Ligation
No full textInternational audienceGuanidine hydrochloride and acetonitrile strongly inhibit Native Chemical Ligation (NCL). These effects, considered alongside the cosolvents' impact on water structure, suggest that water actively participates in NCL.</div
Assessment of the in vitro activity and selectivity of Artemisia afra and Artemisia annua aqueous extracts against artemisinin-resistant Plasmodium falciparum
No full textInternational audienceBackgroundThe recent emergence of artemisinin resistance in Africa is drawing scrutiny toward the use of alternative anti-malarial therapy based on Artemisia annua and Artemisia afra phytotherapies. This study aimed to determine if either A. annua and A. afra extracts are active against artemisinin-resistant Plasmodium falciparum isolates and determine the selectivity of inhibitory phytotherapies.MethodsArtemisia extracts were tested in vitro to mimic parasites exposure to extracts in population drinking Artemisia sp. teas. Artemisia extracts were tested in Ring Stage Survival Assays (RSA0−3 h) against Cambodian clinical isolates previously genetically and phenotypically characterized as artemisinin resistant or sensitive. Primary human hepatocytes and a human hepatoblastoma cell line (HepG2 cells) were used to assess the cytotoxicity of Artemisia extracts.ResultsThe study revealed a substantially decreased in vitro activity of A. annua extracts when tested on artemisinin-resistant parasites mutated in the Pfkelch13 gene (RSA50 0.137–2.56 g.L−1) compared to artemisinin-sensitive parasites (RSA50 0.080 g.L−1). Conversely, the A. afra extracts have a similar activity on the isolates tested whether they are sensitive or resistant to artemisinin (RSA50 0.537–0.758 g.L−1) However, the selectivity index for A. afra extracts was much lower than for A. annua extracts (A. afra: 4.628, 4.305 and 6.076 vs A. annua: 387.625, 226.350 and 12.099, respectively for WT, C580Y and R539T).ConclusionsArtemisia annua activity is driven by artemisinin, implicating the same resistance profiles and concerns associated with semisynthetic artemisinin derivatives. Artemisia afra showed artemisinin-independent antiplasmodial activity. However, the molecular basis of this activity is unknown and may not present a sufficient selectivity, thus further characterization of A. afra is essential
Early growth restriction disrupts mice intestinal clock and homeostasis without being prevented by lactoferrin.
No full textInternational audienceBackgroundPreterm infants and growth-restricted newborns are highly susceptible to intestinal inflammation and sepsis. We studied the effects of oral supplementation with bovine lactoferrin (bLf) during lactation in postnatal growth-restricted (PNGR) mice on intestinal development and susceptibility to colitis at weaning.MethodsGrowth restriction was induced in FVB/NRj mice from large litters from postnatal day (PN) 4 to 21. bLf (300 mg/kg/d) was administered from PN8 to PN21. Intestinal function was evaluated at PN21 by morphology, RNA sequencing, microbiota composition, and cecal short chain fatty acid levels. At PN22, acute colitis was induced by 3% dextran sulfate sodium (DSS). Colitis severity was assessed at PN29 histologically and RT-qPCR.ResultsPNGR altered the expression of genes related to circadian rhythm in intestines but did not increase susceptibility to DSS-induced acute colitis post weaning. PNGR-induced growth retardation and intestinal immaturity were not improved by bLf supplementation. bLf supplementation affected the microbiota composition in control, but not PNGR pups, and slightly reduced the inflammatory effects of colitis in PNGR.ConclusionPNGR alters intestinal development by affecting the intestinal transcriptome during lactation. bLf supplementation does not prevent growth restriction effects on gut health but could modulate gut microbiota in control pups during this period.ImpactPostnatal growth restriction induces changes in the intestinal transcriptome with a disruption of clock-related gene expression.Postnatal growth restriction alters intestinal microbiota composition but does not amplify the response to an inflammatory-induced acute colitis after weaning.Bovine lactoferrin supplementation does not improve an induced growth restriction and its altered intestinal barrier structure.Bovine lactoferrin supplementation may induce positive intestinal microbial changes especially in control mice during lactation
Comprehensive Tools for Culturing Blastocystis : A Standardized Resource for Research and Diagnostics
No full textInternational audienceAbstract Blastocystis spp. is a widely prevalent anaerobic protozoan of uncertain pathogenicity found in the gastrointestinal tracts of over 1 billion people worldwide. Despite its potential significance in health and disease, Blastocystis spp. remains challenging to culture axenically due to its anaerobic nature and the diversity of its genetic subtypes. This manuscript presents a standardized toolkit for culturing Blastocystis spp. in xenic and axenic conditions, detailing protocols for the preparation of appropriate liquid and solid media, cryopreservation, and inoculation. By providing a comprehensive set of tools and methodologies, this work aims to streamline research on Blastocystis spp., enabling reproducibility, subtype characterization, and advancements in understanding its role in the gut microbiome and host health. © 2025 The Author(s). Current Protocols published by Wiley Periodicals LLC. Basic Protocol 1 : Establishment of xenic Blastocystis culture from stool samples in liquid medium Basic Protocol 2 : Subculturing from existing Blastocystis liquid culture Support Protocol 1 : Preparation of modified Jones’ medium for Blastocystis culturing Support Protocol 2 : Preparation of trypticase‐yeast extract‐serum‐gastric mucin‐9 (TSGYM‐9) medium for Blastocystis culturing Support Protocol 3 : Preparation of liver extract‐yeast extract‐serum‐gastric mucin (LYSGM) medium for Blastocystis culturing Basic Protocol 3 : Subculturing xenic Blastocystis cultures in diphasic medium Support Protocol 4 : Preparation of Robinson's medium for Blastocystis culturing Support Protocol 5 : Preparation of Ringer's agar slants for Blastocystis culturing Basic Protocol 4 : Axenization of Blastocystis cultures Basic Protocol 5 : Subculturing axenic Blastocystis cultures in diphasic medium Support Protocol 6 : Preparation of Boeck and Drbohlav's Locke‐egg serum (LES) medium for Blastocystis culturing Support Protocol 7 : Preparation of Boeck and Drbohlav's diphasic modified medium (BDMM) for Blastocystis culturing Basic Protocol 6 : Establishment of axenic Blastocystis cultures in Iscove's modified Dulbecco's medium (IMDM) Basic Protocol 7 : Establishment of axenic Blastocystis cultures in soft IMDM agar Basic Protocol 8 : Establishment of axenic Blastocystis cultures on solid IMDM agar Basic Protocol 9 : Optimized method for establishing axenic Blastocystis cultures on solid IMDM agar Basic Protocol 10 : Establishment of axenic Blastocystis cultures in semi‐solid Locke's agar Basic Protocol 11 : Cryopreservation of xenic Blastocystis cultures Basic Protocol 12 : Cryopreservation of axenic Blastocystis cultures Basic Protocol 13 : Inoculation of liquid medium with xenic Blastocystis cultures from frozen stocks Basic Protocol 14 : Inoculation of liquid medium with axenic Blastocystis cultures from frozen stock
Gut microbiota alterations are linked to COVID-19 severity in North African and European populations
No full textInternational audienceAlthough COVID-19 primarily affects the respiratory system, many patients experience gastrointestinal symptoms, suggesting a role for the gut microbiota in disease pathogenesis. To explore this, we performed shotgun metagenomic sequencing on stool samples from 200 COVID-19 patients and 102 healthy controls in Morocco and France. Despite geographic differences in microbiota composition, patients with COVID-19 in both continents exhibited significant gut microbiota alterations, which were more pronounced in severe cases, with similar features compared with controls. Functional pathways, including L-Tryptophan biosynthesis, were disrupted, particularly in patients with severe disease. Machine learning models accurately predicted disease severity based on gut microbial profiles in the Moroccan cohort, though not in the French cohort. These results highlight consistent microbiota changes associated with COVID-19 and support a potential link between gut dysbiosis and disease severity.The ongoing coronavirus disease 19 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has been a major cause of death worldwide in the last three years (World Health Organization). Although COVID-19 is a respiratory illness, about 10-20% of patients suffer from gastrointestinal symptoms, including loss of appetite, diarrhea, nausea, and vomiting 1,2 . These symptoms are often associated with a high level of fecal calprotectin (an indicator of intestinal inflammation) and interleukin 18 (IL-18, a cytokine that mediates intestinal inflammatory reactions) in patients' stools 3,4 . COVID-19 RNA and, more rarely, infectious viruses can be detected in infected patients' fecal samples, suggesting that the gastrointestinal tract is a major target organ of SARS-CoV-2 infection 5,6 . Moreover, the Angiotensin-Converting Enzyme 2 (ACE2) and transmembrane serine protease 2 (TMPRSS2), both critical proteins for entry of SARS-CoV-2 into host cells, are expressed at high levels in the gastrointestinal epithelial cells 7 .Increasing evidence from preclinical models and clinical studies suggests that SARS-CoV-2 infection leads to alterations of the gut microbiota and that gut dysbiosis could be involved in COVID-19 severity 8-15 . Patients experiencing severe COVID-19 have significant alterations in gut microbiota's composition, characterized by a loss of microbial diversity and richness. In several cohorts, SARS-CoV-2 infection was associated with depletion of beneficial taxa, including butyrate producers (e.g., genera from the Ruminococcaceae family) and bacterial species with known immunomodulatory potential (e.g., Faecalibacterium prausnitzii and Eubacterium rectale) 10,16-18 . In contrast, enrichment of potential opportunistic pathobionts was reported in COVID-19 patients, such as Bacteroides nordii, Rothia, Actinomyces, Ruminococcus, and Clostridium hathewayi 10,16-19 . Of interest, a limited number of studies, mostly in Asian populations, pointed out stronger microbiota alterations in patients developing severe COVID-19 15,20,21 . Beyond the taxonomy, recent studies have shown functional alterations linked to COVID-19, including metabolic pathways related to SCFA production and bile acid metabolism 12,22 . However, only European, North American, and Asian populations have been studied in this regard, and no data are available for African patients suffering from COVID-19 infection.In the current study, we compared the gut microbiota of 200 patients with COVID-19 and 102 healthy subjects from Moroccan and French cohorts. Through shotgun metagenomics and targeted quantitative metabolomics, we showed that COVID-19 infection is associated with alterations in the gut microbiota diversity, composition, and functions in both populations. Interestingly, we found common signals in the patients from the two continents. The strength of the alterations is more marked in severe COVID-19 patients. Finally, we showed that a machine learning-based approach using only bacterial taxa could predict COVID-19 infection severity with high accuracy, but it was not transposable from one population to the other
Evolutionarily conserved grammar rules viral factories of amoeba-infecting members of the hyperdiverse Nucleocytoviricota phylum
No full textInternational audienceDespite sharing fewer than 10 core genes, the hyperdiverse Nucleocytoviricota phylum (ranging from poxviruses to giant viruses) universally assembles viral factories (VFs) resembling biomolecular condensates. Regardless, it is unclear how these viruses achieve such a level of functional conservation without clear conserved genetic information. We demonstrate that the VFs produced by amoeba-infecting viruses have liquid-like properties and identify a conserved molecular grammar governing viral factory scaffold protein: charge-patterned intrinsically disordered regions that drive phase separation independently of sequence homology. This grammar predicts functional scaffold proteins across the 15 viral families, revealing evolutionary constraints invisible to sequence or structural analysis. Strikingly, VFs exhibit subcompartmentalization analogous to nuclei, segregating transcription and mRNA processing (inner condensates) from replication (interphase zones) and translation (host cytoplasm). Our work establishes phase separation as a fundamental organizational principle bridging extreme genomic diversity, explaining how biological complexity emerges without gene conservation. This grammar is likely also conserved in non-amoeba-infecting members of the phylum and thus may represent a primordial solution for organelle-like organization, with broad implications for antiviral targeting