Synovialosarcome cervical: a propos d’un cas

Introduction : Le synovialosarcome est une tumeur maligne agressive. Les localisations cervico-faciales sont très rares. Nous rapportons un nouveau cas de synovialosarcome dans la région antéro-latérale du cou.Observation : Il s’agit d’un patient âgé de 37 ans, qui a consulté pour une volumineuse tuméfaction latéro-cervicale évoluant depuis 8 mois. La TDM a montré une masse tissulaire bien limitée de la région antérolatérale gauche du cou qui se rehausse faiblement après injection de produit de contraste. Le patient a eu une exérèse tumorale complète. L’examen anatomopathologique a conclu à un synovialosarcome. L’évolution était marquée par la récidive locale rapide, après 15 jours, pour laquelle il a été réopéré avec une radio-chimiothérapie post opératoire. Cependant le patient a présenté une métastase pulmonaire avec une poursuite évolutive.Conclusion : Le synovialosarcome cervical ne présente pas de spécificité clinique et radiologique. Le traitement de choix est la chirurgie.La valeur du traitement adjuvant n’est pas encore bien définie. Le pronostic est mauvais.Mots clés : synovialosarcome, région cervicale, chirurgie, radiothérapie, récidiveIntroduction : The synovial sarcoma is a malignant and aggressive tumor. The cervicofacial locations are rares. We report a new case of synovial sarcoma in the anterolateral region of the neck.Observation : He is a 37 years old patient, with a large latero-cervical tumefaction evolving for 8 months. CT showed well circumscribed tissue mass of the left anterolateral area neck which enhances low after contrast injection. The patient had a complete tumor resection. Histological examination concluded a synovial sarcoma. The evolution was marked by rapid local recurrence, after 15 days, for which he was reoperated with postoperative chemoradiotherapy. However, the patient had a pulmonary metastasis with continued progression.Conclusion : The cervical synovial sarcoma has no specific clinical and radiological character. The treatment of choice is surgery. The value of adjuvant therapy is not well defined. The prognosis is poor.Keywords : synovial sarcoma, neck, surgery, radiotherapy, recurrenc

Structural characterization of Si(m)Ge(n) strained layer superlattices

SimGen strained layer superlattice (SLS) structures were grown by molecular beam epitaxy on GexSi1-x buffer layers on Si substrates to determine the effects of buffer layer composition, SLS thickness ratio, and superlattice periodicity, on the overall quality of these structures. X-ray diffraction methods were used to determine how closely actual periodicities and compositions met targeted values, and to evaluate the quality of these samples. In most instances the as-grown structures matched the targeted values to within 10%, though in some instances deviations of 20-25% in either the period or composition were observed. The quality of the SLS structures was greatly dependent on the composition of the buffer layer on which it was grown. SimGen SLS structures grown on Si- and Ge-rich buffer layers were of much higher quality than SimGem SLSs grown on Ge0.50Si0.50 layers, but the x-ray rocking curves of the SimGen samples indicated that they were far from perfect and contained moderate levels of defects. These results were confirmed by cross sectional transmission electron microscopy, which showed that the SimGem structures contained significant numbers of dislocations and that the layers were nonuniform in thickness and wavy in appearance. SimGen structures, however, displayed fewer defects but some dislocations and nonparallelism of layers were still observed

Effect of Hetrovalent substitution at Mn site on the Magnetic and Transport Properties of La0.67_{0.67}Sr0.33_{0.33}MnO3_3

Magnetic and transport properties of Ti substituted La$_{0.67}$Sr$_{0.33}$MnO$_3$ are drastically affected with a change in preparation conditions. Low temperature infra-red absorption measurements reveal that this is perhaps due to inhomogeniety in substitution of Ti$^{4+}$ on Mn sites. It is found that, in the high temperature annealed samples, the substitution of Ti supresses the double exchange interaction due to the formation of Mn$^{3+}$-O-Ti$^{4+}$ chains. While in the low temperature annealed case substitution of Ti causes formation of isolated ferromagnetic clusters linked to each other by a variable range hopping polaron.Comment: 11 pages, 8 figures, accepted in J. Magn. Magn. Magn. Mate

Acinetobacter nematophilus sp. nov., Alcaligenes nematophilus sp. nov., Enterobacter nematophilus sp. nov., and Kaistia nematophila sp. nov., Isolated from Soil-Borne Nematodes and Proposal for the Elevation of Alcaligenes faecalis subsp. faecalis, Alcaligenes faecalis subsp. parafaecalis, and Alcaligenes faecalis subsp. phenolicus to the Species Level.

Four bacterial strains, A-IN1T, A-TC2T, E-TC7T, and K-TC2T, isolated from soil-borne nematodes of the species Oscheius tipulae and Acrobeloides bodenheimeri, were found to represent new species of the genera Acinetobacter, Alcaligenes, Enterobacter, and Kaistia, respectively. In this study, we described these new species using a polyphasic taxonomic approach that included wholegenome and whole-proteome phylogenomic reconstructions, core genome sequence comparisons, and phenotypic characterization. Phylogenomic reconstructions using whole-genome and wholeproteome sequences show that A-IN1T is closely related to Acinetobacter guillouiae DSM 590T and to Acinetobacter bereziniae LMG 1003T. The dDDH values between A-IN1T and these latest strains are 25.1 and 39.6%, respectively, which are below the 70% divergence threshold for prokaryotic species delineation. A-TC2T is closely related to Alcaligenes faecalis subsp. faecalis DSM 30030T and to Alcaligenes faecalis subsp. phenolicus DSM 16503T. The dDDH values between A-TC2T and these latest strains are 47.0 and 66.3%, respectively. In addition, the dDDH values between Alcaligenes faecalis subsp. faecalis DSM 30030T, Alcaligenes faecalis subsp. phenolicus DSM 16503T, and Alcaligenes faecalis subsp. parafaecalis are always lower than 70%, demonstrating that the three strains represent species within the genus Alcaligenes rather than subspecies within Alcaligenes faecalis. E-TC7T is closely related to Enterobacter kobei DSM 13645T, Enterobacter chuandaensis 090028T, and to Enterobacter bugandensis STN0717-56T. The dDDH values between E-TC7T and these strains are 43.5, 42.9, and 63.7%, respectively. K-TC2T is closely related to Kaistia terrae DSM 21341T and to Kaistia defluvii JCM 18034T. The dDDH values between these strains are 29.2 and 30.7%, respectively. Several biochemical tests allow to differentiate the type strains of the newly described species from the type strains of their more closely related species. Based on the results of this polyphasic taxonomic approach, the following new species are proposed: Acinetobacter nematophilus sp. nov. with A-IN1T (=CCM 9231T =CCOS 2018T) as the type strain, Alcaligenes nematophilus sp. nov. with A-TC2T (=CCM 9230T =CCOS 2017T) as the type strain, Enterobacter nematophilus sp. nov. with E-TC7T (=CCM 9232T =CCOS 2020T) as the type strain, and Kaistia nematophila sp. nov. with K-TC2T (=CCM 9239T =CCOS 2022T) as the type strain. In addition, we propose the elevation of Alcaligenes faecalis subsp. faecalis, Alcaligenes faecalis subsp. parafaecalis, and Alcaligenes faecalis subsp. phenolicus to the species level. Therefore, we propose the creation of Alcaligenes parafaecalis sp. nov. with DSM 13975T as the type strain, and Alcaligenes phenolicus sp. nov. with DSM 16503T as the type strain. Our study contributes to a better understanding of the biodiversity and phylogenetic relationships of bacteria associated with soil-borne nematodes