Les tumeurs oncocytaires de la thyroide : a propos de 25 cas

But : Les tumeurs à cellules oncocytaires de la thyroïde (TOT) ont donné jusqu’à ces dernières années de nombreuses controverses, du fait des difficultés à différencier les tumeurs bénignes des tumeurs malignes, entraînant des attitudes thérapeutiques divergentes. L’objectif de cette étude est de voir à travers une revue de littérature les aspects cliniques et pathologiques particuliers aux tumeurs oncocytaires de la thyroïde et d’essayer de réunir les éléments cliniques et anatomopathologiques pouvant prédire l’aspect malin de ces tumeurs. Méthodes : Il s’agit d’une étude rétrospective menée sur une période de 19 ans étalée de janvier 1988 à décembre 2006, pendant laquelle nous avons colligé 25 cas de tumeurs oncocytaires de la thyroïde. La circonstance de découverte était un nodule thyroïdien pour tous les patients. Resultats : Notre travail repose sur une série de 25 tumeurs oncocytaires de la thyroïde, dont 3 cancers oncocytaires (12%). Ces tumeurs représentent 1,2% des tumeurs thyroïdiennes opérées durant la même période. L’âge moyen des patients ayant eu un carcinome oncocytaire était de 65 ans, la taille moyenne de ces carcinomes était de 4 cm. Le traitement a consisté en une loboisthmectomie pour les adénomes et en une thyroïdectomie totale associée à un curage ganglionnaire cervical suivi d’une irathérapie pour les carcinomes. Une seule patiente ayant présenté un carcinome oncocytaire a développé une métastase à distance. L’évolution était favorable chez tous les autres patients avec recul variable de 9 mois à 22 ans avec une moyenne de 5 ans. Conclusion : Les tumeurs oncocytaires de la thyroïde sont reconnues à la lumière des travaux récents comme une entité anatomo-clinique particulière, se différenciant des tumeurs vésiculaires (auxquelles elles ont été longtemps assimilées) par une évolution plus péjorative et par une insensibilité à l’iode radioactif avec une fréquence accrue de métastases pour les carcinomes.Mots clés : tumeur oncocytaire, tumeur à cellules de Hurthle, cancer de la thyroïde, thyroidectomie

Améloblastome mandibulaire place de la radiothérapie

L’améloblastome est la tumeur odontogénique la plus fréquente. il  représente 1% des tumeurs mandibulaires et maxillaires et atteint la mandibule dans 80% des cas. Son traitement se base essentiellement sur la chirurgie lorsque cela est possible. La radiothérapie est réservée aux formes inopérables localement évoluées et métastatiques. Les auteurs rapportent le cas d’un patient présentant un améloblastome mandibulaire kystique traité par radiothérapie exclusive.Mots clés: Améloblastome, mandibule, radiothérapi

Stenose tracheale post-intubation

Objective : Remind the main post-intubation tracheal stenosis etiopathogenic characteristics, specify the preoperative assessment and discuss the different therapeutic modalities.Materials and methods : This retrospective study includes 28 cases of scarring tracheal stenosis treated between 1987 and 2003.Results : They are acquired, secondary to intubation and / or tracheotomy. The results of our study highlight the important role of medical and endoscopic treatment. However, the best treatment of tracheal stenosis remains the surgical treatment based on tracheal resection anastomosis, 89% of good results in our study.Conclusion : Our results indicate that the endoscopic treatment of post-intubation tracheal stenoses can be considered a safe first-line therapy, leaving the complex and relapsing stenoses, for surgical resection.Keywords : Tracheal stenosis, tracheal intubation, tracheotomy

α7-Nicotinic Acetylcholine Receptor: Role in Early Odor Learning Preference in Mice

Recently, we have shown that mice with decreased expression of α7-nicotinic acetylcholine receptors (α7) in the olfactory bulb were associated with a deficit in odor discrimination compared to wild-type mice. However, it is unknown if mice with decreased α7-receptor expression also show a deficit in early odor learning preference (ELP), an enhanced behavioral response to odors with attractive value observed in rats. In this study, we modified ELP methods performed in rats and implemented similar conditions in mice. From post-natal days 5–18, wild-type mice were stroked simultaneously with an odor presentation (conditioned odor) for 90 s daily. Control mice were only stroked, exposed to odor, or neither. On the day of testing (P21), mice that were stroked in concert with a conditioned odor significantly investigated the conditioned odor compared to a novel odor, as observed similarly in rats. However, mice with a decrease in α7-receptor expression that were stroked during a conditioned odor did not show a behavioral response to that odorant. These results suggest that decreased α7-receptor expression has a role in associative learning, olfactory preference, and/or sensory processing deficits

Genetic Relationship between Cocirculating Human Enteroviruses Species C

Recombination events between human enteroviruses (HEV) are known to occur frequently and to participate in the evolution of these viruses. In a previous study, we reported the isolation of a panel of viruses belonging to the Human enterovirus species C (HEV-C) that had been cocirculating in a small geographic area of Madagascar in 2002. This panel included type 2 vaccine-derived polioviruses (PV) that had caused several cases of acute flaccid paralysis in humans. Previous partial sequencing of the genome of these HEV-C isolates revealed considerable genetic diversity, mostly due to recombination. In the work presented herein, we carried out a more detailed characterization of the genomes of viruses from this collection. First, we determined the full VP1 sequence of 41 of these isolates of different types. These sequences were compared with those of HEV-C isolates obtained from other countries or in other contexts. The sequences of the Madagascan isolates of a given type formed specific clusters clearly differentiated from those formed by other strains of the same type isolated elsewhere. Second, we sequenced the entire genome of 10 viruses representing most of the lineages present in this panel. All but one of the genomes appeared to be mosaic assemblies of different genomic fragments generated by intra- and intertypic recombination. The location of the breakpoints suggested potential preferred genomic regions for recombination. Our results also suggest that recombination between type HEV-99 and other HEV-C may be quite rare. This first exhaustive genomic analysis of a panel of non-PV HEV-C cocirculating in a small human population highlights the high frequency of inter and intra-typic genetic recombination, constituting a widespread mechanism of genetic plasticity and continually shifting the HEV-C biodiversity

Diazoxide Promotes Oligodendrocyte Precursor Cell Proliferation and Myelination

Several clinical conditions are associated with white matter injury, including periventricular white matter injury (PWMI), which is a form of brain injury sustained by preterm infants. It has been suggested that white matter injury in this condition is due to altered oligodendrocyte (OL) development or death, resulting in OL loss and hypomyelination. At present drugs are not available that stimulate OL proliferation and promote myelination. Evidence suggests that depolarizing stimuli reduces OL proliferation and differentiation, whereas agents that hyperpolarize OLs stimulate OL proliferation and differentiation. Considering that the drug diazoxide activates K(ATP) channels to hyperpolarize cells, we tested if this compound could influence OL proliferation and myelination.Studies were performed using rat oligodendrocyte precursor cell (OPC) cultures, cerebellar slice cultures, and an in vivo model of PWMI in which newborn mice were exposed to chronic sublethal hypoxia (10% O(2)). We found that K(ATP) channel components Kir 6.1 and 6.2 and SUR2 were expressed in oligodendrocytes. Additionally, diazoxide potently stimulated OPC proliferation, as did other K(ATP) activators. Diazoxide also stimulated myelination in cerebellar slice cultures. We also found that diazoxide prevented hypomyelination and ventriculomegaly following chronic sublethal hypoxia.These results identify KATP channel components in OLs and show that diazoxide can stimulate OL proliferation in vitro. Importantly we find that diazoxide can promote myelination in vivo and prevent hypoxia-induced PWMI

Serological monitoring of vaccination against the major avian viral diseases in poultry breeding farms in Tunisia

A sero-epidemiological study was conducted in six broiler breeding companies and four broiler breeding laying hen companies, covering most of the poultry breeding farms in Tunisia. The objective was to evaluate the effectiveness of the immune response following the application of vaccination protocols established by the owners and carried out against the viruses of Newcastle disease (NDV), infectious bronchitis (IBV) and infectious bursal disease (IBD). During eight visits per farm, questionnaires were completed and 2000 samples were taken. The samples were submitted to indirect ELISA using CIVTEST AVINDV, -IBV, and -IBD kits. For each date and each disease, the mean specific antibody titers and the coefficient of variation were calculated. These indicators revealed that the chicks were in good health, the kinetics of post-vaccination antibodies generally satisfactory, and the overall immune response sufficiently uniform. However, the vaccination protocol recommended by the National Commission for Avian Diseases was not always applied. This either caused a temporary drop in antibody levels resulting in a high risk of infection, or necessitated interventions resulting in economic losses because of vaccine-related costs. This work shows the need for farmers to have a database for the establishment of an immunoprophylaxis program adapted to the epidemiological conditions of these farms