Hypertrophie bilatérale du canal du Wharton révélatrice d’un Syndrome de Gougerot Sjögren

Le canal de Wharton draine les secrétions de la glande sousmaxillaire. Les étiologies de la dilatation de ce canal sont nombreuses: mégacanaux salivaires idiopathiques, lithiase salivaire, dilatation canalaire résultant d'une sténose tumorale ou traumatique et calcinose salivaire. Cette dernière est due à la présence de multiples concrétions parenchymateuses bilatérales dans un groupe de glandes. Il existerait une relation entre calcinose et Syndrome de Gougerot Sjögren (SGS). Patiente de 55 ans sans antécédents pathologiques notables était hospitalisée pour exploration d'une hypertrophie du canal de Wharton et une sécheresse buccale et oculaire évoluant depuis un an. L'examen somatique notait une hypertrophie des glandes sous maxillaires, une hypertrophie des canaux de Wharton surtout à droite sans calcul palpable sur leur trajet et l'orifice de Wharton était libre. Le reste de l'examen était sans particularités. La scintigraphie salivaire montrait une perfusion et une captation faible des glandes parotides et sous maxillaires, cet aspect est en faveur d'un syndrome sec. L'échographie cervicale était sans anomalies. Le bilan immunologique (anticorps antinucléaires, anti SSA, anti SSB, facteur rhumatoïde) était positif. Le «Break up time» (BUT) était altéré à 3'' en faveur d'une xérophtalmie. La biopsie des glandes salivaires accessoires objectivait une sialadénite stade III de Chisholm confirmant le diagnostic du SGS et la patiente a été mise sous traitement symptomatique.Pan African Medical Journal 2015; 2

Tunisian Toxoplasma gondii strains genotyping by the use of AK69 marker

<p>Abstract</p> <p>Background</p> <p>Clinical manifestation due to infection by <it>Toxoplasma gondii </it>is closely linked to the infecting strain of the parasite. Several genetic markers are available to determinate its genotype but few of them are able to discriminate between the three predominant lineages, namely types I, II and III. The number of markers decreases when atypical, recombinant/mixed genotypes need to be identified.</p> <p>Findings</p> <p>In our study, the contribution of sequence polymorphisms in the AK69 gene as typing markers for <it>T. gondii </it>was investigated for the first time in an epidemiological study. The coding region of the marker was amplified, sequenced and aligned for different <it>Toxoplasma </it>strains. The identified nucleotide polymorphism at 12 positions was able to highly discriminate between the different congenital toxoplasmosis Tunisian strains. Moreover the high detection sensitivity level of the marker enabled unambiguous identification of mixed/recombinant genotypes directly.</p> <p>Conclusion</p> <p>It can be, thus, very useful for direct typing in areas where such genotypes are frequently encountered, mainly in the African continent.</p

A STAT3-decoy oligonucleotide induces cell death in a human colorectal carcinoma cell line by blocking nuclear transfer of STAT3 and STAT3-bound NF-κB

<p>Abstract</p> <p>Background</p> <p>The transcription factor STAT3 (signal transducer and activator of transcription 3) is frequently activated in tumor cells. Activated STAT3 forms homodimers, or heterodimers with other TFs such as NF-κB, which becomes activated. Cytoplasmic STAT3 dimers are activated by tyrosine phosphorylation; they interact with importins via a nuclear localization signal (NLS) one of which is located within the DNA-binding domain formed by the dimer. In the nucleus, STAT3 regulates target gene expression by binding a consensus sequence within the promoter. STAT3-specific decoy oligonucleotides (STAT3-decoy ODN) that contain this consensus sequence inhibit the transcriptional activity of STAT3, leading to cell death; however, their mechanism of action is unclear.</p> <p>Results</p> <p>The mechanism of action of a STAT3-decoy ODN was analyzed in the colon carcinoma cell line SW 480. These cells' dependence on activated STAT3 was verified by showing that cell death is induced by STAT3-specific siRNAs or Stattic. STAT3-decoy ODN was shown to bind activated STAT3 within the cytoplasm, and to prevent its translocation to the nucleus, as well as that of STAT3-associated NF-κB, but it did not prevent the nuclear transfer of STAT3 with mutations in its DNA-binding domain. The complex formed by STAT3 and the STAT3-decoy ODN did not associate with importin, while STAT3 alone was found to co-immunoprecipitate with importin. Leptomycin B and vanadate both trap STAT3 in the nucleus. They were found here to oppose the cytoplasmic trapping of STAT3 by the STAT3-decoy ODN. Control decoys consisting of either a mutated STAT3-decoy ODN or a NF-κB-specific decoy ODN had no effect on STAT3 nuclear translocation. Finally, blockage of STAT3 nuclear transfer correlated with the induction of SW 480 cell death.</p> <p>Conclusions</p> <p>The inhibition of STAT3 by a STAT3-decoy ODN, leading to cell death, involves the entrapment of activated STAT3 dimers in the cytoplasm. A mechanism is suggested whereby this entrapment is due to STAT3-decoy ODN's inhibition of active STAT3/importin interaction. These observations point to the high potential of STAT3-decoy ODN as a reagent and to STAT3 nucleo-cytoplasmic shuttling in tumor cells as a potential target for effective anti-cancer compounds.</p

The effect of post-lunch napping on mood, reaction time, and antioxidant defense during repeated sprint exercice

To compare the effects of two nap opportunities (20 and 90 min) to countermeasure the transient naturally occurring increased sleepiness and decreased performances during the post-lunch dip (PLD). Fourteen highly trained judokas completed in a counterbalanced and randomized order three test sessions (control (No-nap), 20- (N20) and 90-min (N90) nap opportunities). Test sessions consisted of the running-based anaerobic sprint test (RAST), simple and multiple-choice reaction times (MCRT) and the Epworth sleepiness scale (ESS). From the RAST, the maximum (Pmax), mean (Pmean) and minimum (Pmin) powers were calculated. Blood samples were taken before and after the RAST to measure the effect of pre-exercise napping on energetic and muscle damage biomarkers and antioxidant defense. N20 increased Pmax and Pmean compared to No-nap (p < 0.001, d = 0.59; d = 0.66) and N90 (p < 0.001, d = 0.98; d = 0.72), respectively. Besides, plasma lactate and creatinine increased only when the exercise was performed after N20. Both N20 (p < 0.001, d = 1.18) and N90 (p < 0.01, d = 0.78) enhanced post-exercise superoxide dismutase activity compared to No-nap. However, only N20 enhanced post-exercise glutathione peroxidase activity (p < 0.001, d = 1.01) compared to pre-nap. Further, MCRT performance was higher after N20 compared to No-nap and N90 (p < 0.001, d = 1.15; d = 0.81, respectively). Subjective sleepiness was lower after N20 compared to No-nap (p < 0.05, d = 0.92) and N90 (p < 0.01, d = 0.89). The opportunity to nap for 20 min in the PLD enhanced RAST, MCRT performances, and antioxidant defense, and decreased sleepiness. However, the opportunity of 90 min nap was associated with decreased repeated sprint performances and increased sleepiness, probably because of the sleep inertia

The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance

INTRODUCTION Investment in Africa over the past year with regard to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing has led to a massive increase in the number of sequences, which, to date, exceeds 100,000 sequences generated to track the pandemic on the continent. These sequences have profoundly affected how public health officials in Africa have navigated the COVID-19 pandemic. RATIONALE We demonstrate how the first 100,000 SARS-CoV-2 sequences from Africa have helped monitor the epidemic on the continent, how genomic surveillance expanded over the course of the pandemic, and how we adapted our sequencing methods to deal with an evolving virus. Finally, we also examine how viral lineages have spread across the continent in a phylogeographic framework to gain insights into the underlying temporal and spatial transmission dynamics for several variants of concern (VOCs). RESULTS Our results indicate that the number of countries in Africa that can sequence the virus within their own borders is growing and that this is coupled with a shorter turnaround time from the time of sampling to sequence submission. Ongoing evolution necessitated the continual updating of primer sets, and, as a result, eight primer sets were designed in tandem with viral evolution and used to ensure effective sequencing of the virus. The pandemic unfolded through multiple waves of infection that were each driven by distinct genetic lineages, with B.1-like ancestral strains associated with the first pandemic wave of infections in 2020. Successive waves on the continent were fueled by different VOCs, with Alpha and Beta cocirculating in distinct spatial patterns during the second wave and Delta and Omicron affecting the whole continent during the third and fourth waves, respectively. Phylogeographic reconstruction points toward distinct differences in viral importation and exportation patterns associated with the Alpha, Beta, Delta, and Omicron variants and subvariants, when considering both Africa versus the rest of the world and viral dissemination within the continent. Our epidemiological and phylogenetic inferences therefore underscore the heterogeneous nature of the pandemic on the continent and highlight key insights and challenges, for instance, recognizing the limitations of low testing proportions. We also highlight the early warning capacity that genomic surveillance in Africa has had for the rest of the world with the detection of new lineages and variants, the most recent being the characterization of various Omicron subvariants. CONCLUSION Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve. This is important not only to help combat SARS-CoV-2 on the continent but also because it can be used as a platform to help address the many emerging and reemerging infectious disease threats in Africa. In particular, capacity building for local sequencing within countries or within the continent should be prioritized because this is generally associated with shorter turnaround times, providing the most benefit to local public health authorities tasked with pandemic response and mitigation and allowing for the fastest reaction to localized outbreaks. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century

Solving numeric problems in Tunisian context : normative and neuropsychological approach

Bien qu’elle constitue une piste prometteuse dans le champ de la neuropsychologie, la question de résolution de problèmes reste un domaine très peu exploré par les chercheurs. Dans cette optique et afin d’étudier le fonctionnement exécutif, nous avons fait recours à un protocole comportant des problèmes solubles et d’autres insolubles (auxquels il n’y a pas de réponses possibles) auprès d’une population tunisienne saine et pathologique. Ainsi, dans une étude préliminaire, la moitié des sujets sains tunisiens résolvait les problèmes insolubles en dépit de tout dysfonctionnement exécutif, une perturbation qui semble spécifique à la pathologie frontale d’après la littérature. Afin d’expliquer ce comportement de résolution, plusieurs explications ont été évoquées notamment exécutive en termes d’adhérence cognitive (Le Gall et al., 2001), mais aussi sociocognitive en lien avec le besoin d’approbation sociale plus particulièrement (Souissi, 2013). En effet, l’objectif de la présente recherche est d’examiner la capacité de résolution de problèmes numériques auprès de la population tunisienne saine et malade et expliquer plus particulièrement le comportement de résolution de problèmes insolubles précédemment décrit chez certains d’entre eux. Nous explorerons plus particulièrement les performances des sujets tunisiens sains (n=45) comparés à des malades porteurs de lésions frontales (n=21) et postérieures (n=11). Nous examinerons l’impact des variables socioculturelles telles que la désirabilité sociale, l’orientation culturelle et la dépendance au contexte sur l’ensemble des performances. Les résultats plaident en faveur d’un lien entre la résolution de problèmes solubles et les fonctions exécutives chez les trois groupes de participants. En revanche, la résolution de problèmes insolubles semble expliquée par la désirabilité sociale chez les sujets contrôles alors qu’elle est liée à un dysfonctionnement exécutif chez les malades frontaux.Although it is a promising topic in the field of neuropsychology, the question of problem solving remains a largely unexplored field of study for researchers. In order to study executive function, we used a protocol that contains both soluble problems and insoluble ones (if they dot not have possible answers), by observing Tunisian participants who are either healthy or patients with brain damage. Thus, in a preliminary study, half of the Tunisian healthy subjects proposed solutions for insoluble problems, outside of any executive dysfunction. This disturbance seemsto be a specific charasteristic of frontal pathology according to the literature.In order to explain this problem solving behavoiur, several explanation were mentionned, notably an executive explanation in terms of cognitive adhesion (Le Gall et al., 2001), but also a sociocognitive one in relation to the need for social approval (Souissi, 2013).In fact, the main objective of this research is to examine this cognitive adherence among the Tunisain healthy subjects and cerebrospinate patients, while explaining this problem-solving behavior for insoluble questions ; a behavior that was previously described in some of them. We explore the performance of Tunisian healthy subjects (n=45) compared to patients with frontal (n=21) and posterior (n=11) lesions. We will also examine the impact of sociocultural variables , such as social desirability, cultural orientation and contextual dependance, on overall performances. Th result argue in favor of a link between solving soluble problems and executive functions in the three groups of participants. However, solving insoluble problems seems to be explained by social desirability for healthy subjects, while it is linked to executive dysfunctionfor patients with frontal lesions

Résilience et capacité d'adaptation des systèmes d'exploitation agricoles méditerranéens aux changements climatiques : application à la basse vallée de Medjerda-Tunisie

Le changement climatique menacera probablement la durabilité de la plupart des systèmes agricoles en région méditerranéenne et notamment au sud de la méditerranée. Le comportement des systèmes agricoles sera différent selon les régions sur la base de contextes biophysique, socio-économique, institutionnel et politique. L'objectif de cette thèse est d'analyser la résilience et la capacité d'adaptation au changement climatique des exploitations agricoles en prenant comme référence celles de la Basse Vallée de Medjerda (Nord de la Tunisie). Pour répondre à cet objectif, trois questions principales sont successivement abordées. Le premier chapitre décrit, en se basant sur une large revue de littérature, les effets agri environnementaux du changement climatique en région méditerranéenne et particulièrement en Tunisie. Le deuxième chapitre analyse les effets potentiels du changement climatique sur la résilience des exploitations agricoles de la Basse Vallée de Medjerda (BVM). Pour faire bref, la résilience d'une exploitation est sa capacité à assurer par elle-même sa viabilité économique et par conséquent sa pérennité. Pour ce faire, un cadre conceptuel a été construit. Ce cadre est basé sur trois étapes impliquant la définition de l'échelle spatiale, les forces exogènes, les indicateurs et les seuils de persistance. A cet effet, une chaîne de modèles biophysique-socioéconomique au niveau régional a été utilisée pour simuler l'effet du changement climatique d'une part sur les rendements des cultures et sur la salinité du sol à l'échelle de la parcelle, et d'autre part sur la résilience et la capacité d'adaptation des exploitations agricoles. Cette approche quantitative permet la simulation de stratégie d'adaptation agricole système en calculant trois indicateurs : le stock de terres, le stock de main-d'œuvre et le flux des revenus, en réponse au changement climatique. Le troisième chapitre évalue les stratégies d'adaptation possibles permettant de faire face aux effets du changement climatique. Ces stratégies ont été identifiées dans le cadre d'une approche participative, en concertation avec les agriculteurs et les experts locaux au niveau de la BVM et simulées en utilisant la chaîne de modèles. Les résultats de cette étude montrent une hétérogénéité des comportements des exploitations agricoles en fonction de la diversité et du degré d‘intensification des activités de production agricoles (végétale et animale). Les exploitations agricoles les plus diversifiées et les moins intensifiées avec une activité animale importante semblent être plus résilientes au changement climatique que les exploitations spécialisées ayant un système de production intensif. Nous constatons que les stratégies d'adaptation basées sur l'augmentation des doses d'irrigation pour satisfaire les besoins croissants en eau des cultures, l'irrigation de complément des céréales, et l'amélioration de l'efficience des systèmes d'irrigation améliorent la résilience des exploitations agricoles de la Basse Vallée de Medjerda. Ces stratégies ont un effet plus important sur la profitabilité des exploitations agricoles si elles sont accompagnées par une tarification d'eau binôme. Les résultats de cette étude montrent que les systèmes agricoles peuvent s'adapter au changement climatique de différentes façons. La méthodologie utilisée peut être adaptée à d'autres régions de la Méditerranée et permettra d'aider les experts et les décideurs politiques à proposer et tester des stratégies d'adaptation au changement climatique dans ces régions.Climate change would impact sustainability of most agricultural systems in the Mediterranean region and particularly in the south of the Mediterranean. It is expected that agricultural systems react differently depending on biophysical, socioeconomic and political contexts of each agriculture. The objective of this thesis is to analyze the resilience and adaptive capacity to climate change of the farming systems of the Low Valley of Medjerda (Northern Tunisia). To meet this objective, three main steps are developed. The first chapter describes, based on a literature review, the agri-environmental effects of climate change in the Mediterranean region and particularly in Tunisia. The second chapter analyzes the potential impact of climate change on the resilience of the farming systems in the Low Valley of Medjerda (LVM). To do this, an operational Framework was built. The third chapter assesses the possible adaptive strategies to cope with the effects of climate change. These strategies have been identified through a participatory approach, in consultation with farmers and local experts in the LVM watershed. For this purpose, a chain of regional biophysical-socio-economic models was used to simulate the effect of climate change, on crop yields and soil salinity at field scale, and on the resilience and adaptability of farming systems. The results of this study show heterogeneous behaviors of farming systems depending on the diversity and the degree of intensification of agricultural production (crop and livestock). More diversified and less intensified farming systems with a large animal activity seem to be more resilient than specialized farms with intensive production system. In addition, as expected, we find that adaptation strategies based on the increasing of irrigation doses to meet the increased crop water requirements (SIrr.am), supplemental irrigation of cereal (SIrr.c) and the improvement of the efficiency of irrigation systems (SIrr.sys)improve the resilience of farming systems in the LVM watershed. These strategies have a greater effect on the profitability of farming systems if they are accompanied by a binominal water tariff. The methodology used in this research can be adapted for other Mediterranean regions and assist experts and policy makers to propose and test strategies for adapting to climate change in these regions

Résolution de problèmes numériques en contexte tunisien : approche normative et neuropsychologique.

Although it is a promising topic in the field of neuropsychology, the question of problem solving remains a largely unexplored field of study for researchers. In order to study executive function, we used a protocol that contains both soluble problems and insoluble ones (if they dot not have possible answers), by observing Tunisian participants who are either healthy or patients with brain damage. Thus, in a preliminary study, half of the Tunisian healthy subjects proposed solutions for insoluble problems, outside of any executive dysfunction. This disturbance seemsto be a specific charasteristic of frontal pathology according to the literature.In order to explain this problem solving behavoiur, several explanation were mentionned, notably an executive explanation in terms of cognitive adhesion (Le Gall et al., 2001), but also a sociocognitive one in relation to the need for social approval (Souissi, 2013).In fact, the main objective of this research is to examine this cognitive adherence among the Tunisain healthy subjects and cerebrospinate patients, while explaining this problem-solving behavior for insoluble questions ; a behavior that was previously described in some of them. We explore the performance of Tunisian healthy subjects (n=45) compared to patients with frontal (n=21) and posterior (n=11) lesions. We will also examine the impact of sociocultural variables , such as social desirability, cultural orientation and contextual dependance, on overall performances. Th result argue in favor of a link between solving soluble problems and executive functions in the three groups of participants. However, solving insoluble problems seems to be explained by social desirability for healthy subjects, while it is linked to executive dysfunctionfor patients with frontal lesions.Bien qu’elle constitue une piste prometteuse dans le champ de la neuropsychologie, la question de résolution de problèmes reste un domaine très peu exploré par les chercheurs. Dans cette optique et afin d’étudier le fonctionnement exécutif, nous avons fait recours à un protocole comportant des problèmes solubles et d’autres insolubles (auxquels il n’y a pas de réponses possibles) auprès d’une population tunisienne saine et pathologique. Ainsi, dans une étude préliminaire, la moitié des sujets sains tunisiens résolvait les problèmes insolubles en dépit de tout dysfonctionnement exécutif, une perturbation qui semble spécifique à la pathologie frontale d’après la littérature. Afin d’expliquer ce comportement de résolution, plusieurs explications ont été évoquées notamment exécutive en termes d’adhérence cognitive (Le Gall et al., 2001), mais aussi sociocognitive en lien avec le besoin d’approbation sociale plus particulièrement (Souissi, 2013). En effet, l’objectif de la présente recherche est d’examiner la capacité de résolution de problèmes numériques auprès de la population tunisienne saine et malade et expliquer plus particulièrement le comportement de résolution de problèmes insolubles précédemment décrit chez certains d’entre eux. Nous explorerons plus particulièrement les performances des sujets tunisiens sains (n=45) comparés à des malades porteurs de lésions frontales (n=21) et postérieures (n=11). Nous examinerons l’impact des variables socioculturelles telles que la désirabilité sociale, l’orientation culturelle et la dépendance au contexte sur l’ensemble des performances. Les résultats plaident en faveur d’un lien entre la résolution de problèmes solubles et les fonctions exécutives chez les trois groupes de participants. En revanche, la résolution de problèmes insolubles semble expliquée par la désirabilité sociale chez les sujets contrôles alors qu’elle est liée à un dysfonctionnement exécutif chez les malades frontaux

Effect of submarine morphology on environment quality: Case of Monastir bay (Easter Tunisia)

International audienceThe Monastir Bay is characterized by high organic pollution (up to 6% TOC), along the coastal zone and significant eutrophication. Such degradation seems to be strongly related to both characteristics of the supplied water which is rich in organic particles and the submarine morphology showing a flat extending between Khniss and Lamta and a series of shoals and sand bars between Ras Dimass and Kuriates Islands. Results of the hydrodynamics modeling have shown that the submarine morphology of the bay is responsible for the transformation of the waves coming from the open sea (N, E, SE) to the coastal zone, where reduced energy contributes to the concentration of pollution. Wave modeling has also shown that such concentration prevails in low-depth (0 to -3m depth) areas where both surf and breaking zones are almost absent. This case illustrates an example of the Mediterranean coasts vulnerability to pollution under moderate energy conditions

Coastal erosion in the south-eastern Mediterranean: case of beaches in North Tunisia

(IF 1.14; Q2)International audienceThis research is conducted as part of a Spanish International Cooperation Agency project with the aim to investigate the sustainable protection of Tunisian coastal zones, as in the case of Beni Khiar and Dar Chaabane coasts (Hammamet Gulf) separated by Oued El Kebir river. The sedimentary dynamic of these beaches is studied in order to identify the main causes responsible for their erosion by the use of different approaches of in situ measurements and numerical methods. Geophysical surveys and sedimentary analyses have demonstrated that sediments are finer and less carbonated from Beni Khiar to Dar Chaabane. Then, the shoreline mapping of several missions of aerial photos has illustrated a mean shoreline retreat between 3 and 4 m/year. In terms of sand volume, a sediment loss more than 30,000 m3/year at Dar Chaabane has been observed since the hill lake structures were built within Oued El Kebir river in 1996. Finally, modelled hydrodynamic and sedimentary patterns have illustrated the refraction of waves in deep water close to shoals and a high-energy concentration along Dar Chaabane coast. The sediment transport direction is mainly of NE-SW induced by ESE-SE wave-driven alongshore current. Results provided by these approaches have shown the importance of Oued El Kebir sediment yield in supplying the neighbouring beaches. Changes in sedimentary dynamics are affected by the modification of hydrodynamic patters caused by the presence of hydrological dams and the implementations of hotels close to the shoreline. This finding underlines the key role of Oued El Kebir fluvial activity in controlling the equilibrium of beaches and their sensitivity to coastal managements induced by man activities, as in the case of the most Mediterranean beaches