Phylogenetics of Mycoplasma hominis clinical strains associated with gynecological infections or infertility as disclosed by an expanded multilocus sequence typing scheme

International audienceTo our knowledge, the phylodistribution of M. hominis clinical strains associated with various pathological conditions of the urogenital tract has not been explored hitherto. Here we analyzed the genetic diversity and phylogenetic relationships among 59 M. hominis Tunisian clinical isolates, categorized as gynecological infections-or infertility-associated pathotypes. For this purpose, we developed an expanded multilocus sequence typing (eMLST) scheme, combining the previously reported multilocus sequence typing (MLST) loci (gyrB, tuf, ftsY, uvrA, gap) with a new selected set of putative virulence genes (p120', vaa, lmp1, lmp3, p60), referred herein to as multi-virulence-locus sequence typing (MVLST) loci. In doing so, M. hominis population was segregated into two distinct genetic lineages, which were differentially associated with each pathotype. Such a clear dichotomy was supported by several phylogenetic and population genetic analysis tools. Recombination was found to take place, but not sufficient enough to break down the overall clonal population structure of M. hominis, most likely as a result of purifying selection, which accommodated the most fit clones. In sum, and owing to the eMLST scheme described herein, we provide insightful data on the phylogenetics of M. hominis, arguing for the existence of genetically differentiable urogenital pathotypes. Mycoplasma hominis, which belongs to the Mycoplasmataceae family, in the Mollicutes class, was the first myco-plasma species isolated from humans in 1937 1. It resides, as a commensal, in the lower urogenital tract of healthy persons. Under certain circumstances, M. hominis can cause a variety of genital infections such as bacterial vag-inosis, pelvic inflammatory disease, and cervicitis 2. This microorganism seems to be associated with pregnancy complications and neonatal diseases 3. In addition, several studies reported the pathogenic role of M. hominis in infertility 4,5. More interestingly, this species has been linked to a wide range of extragenital infections (septic arthritis, endocarditis, brain abscess), especially in immunocompromised patients 6-8. To better understand the epidemiology and the mode of spread of M. hominis, several molecular typing systems have been developed. These include Pulse-Field Gel Electrophoresis (PFGE), Restriction Fragment Length Polymorphism (RFLP) analysis, Amplified Fragment Length Polymorphism (AFLP), and Random Amplified Polymorphic DNA (RADP). All these methods have revealed a high degree of both genetic and antigenic het-erogeneity among M. hominis strains 9-12. Although informative, these approaches proved to be quite difficult t

Les Tumeurs Parotidiennes : À Propos De 43 Cas

Les tumeurs des glandes salivaires sont rares, dominées en fréquence par les tumeurs parotidiennes. Elles sont caractérisées par une grande hétérogénéité morpho-histologique. Cliniquement, elles se manifestent le plus souvent par une masse parotidienne non spécifique. A l\'examen histologique, les formes bénignes sont les plus fréquentes dominées par l\'adénome pléomorphe. Le traitement de ces tumeurs demeure chirurgical en premier lieu. Néanmoins, la complication majeure de cette chirurgie reste la paralysie faciale pouvant être transitoire ou permanente. Le but de cet article est d\'analyser chez 43 patients suivis et traités d\'une tumeur parotidienne les différents aspects épidémio- cliniques, radiologiques et histologiques de ces tumeurs.Tumors of the salivary gland are rare, arising predominantly in the parotid gland. They display great pathomorphological variation. Clinically, this tumors manifest, often, as nonspecific parotid masses. Histopathological examination of the tumor specimens\' shows that benign tumors are more frequent, dominated by the pleomorphic adenoma. Treatment of these tumors is mostly surgical. However, facial nerve paralysis remains the main complication of parotid surgery. This study was a retrospective analysis of 43 cases of parotid tumors. Epidemical, clinical, radiological and histological features were studied. Keywords: Tumors, salivary gland, parotid gland, pleomorphic adenoma, benign tumors, surgery, facial nerve paralysis. Journal Tunisien d\'ORL et de chirurgie cervico-faciale Vol. 18 2007: pp. 29-3

Les cellulites cervico-faciales d’origine dentaire: a propos de 150 cas

Les cellulites cervico-faciales d’origine dentaire sont des infections des tissus cellulo-adipeux, de la face et du cou, ayant des potentialités extensives pouvant parfois être graves et engager le pronostic vital. Le but de ce travail est d’étudier le profil épidémioclinique et paraclinique de nos patients, d’évaluer leur prise en charge thérapeutique et leur évolution. Notre étude est rétrospective et a porté sur 150 cas de cellulites cervico-faciales d’origine dentaire colligés sur 10 ans entre 1997 et 2006. La prise en charge thérapeutique était médico-hirurgicale. Les cellulites cervico-faciales d’origine dentaire sont une pathologie potentiellement grave dont la prise en charge est coûteuse et les répercussions socio-professionnelles et économiques sont lourdes d’où l’intérêt d’une politique de prévention efficace et ciblée visant à réduire la morbidité liée à ces infections.Mots clés : cellulites cervicale et faciale, infections dentaire, prévention

Le kyste de la vallecule : a propos de 2 observations

Le kyste de la vallécule est une malformation laryngée rare pouvant parfois mettre en jeu le pronostic vital. Diagnostiqué et traité à temps, le risque de complications et de morbidité peut être écarté. Les auteurs rapportent 2 cas de kystes de la vallécule. La tomodensitométrie a confirmé la présence d’une formation kystique prenant origine au niveau de la vallécule. Une laryngoscopie directe a été faite pour les 2 patients sous anesthésie générale. Le premier malade a eu une résection endoscopique complète du kyste et le 2ème une large marsupialisation au Laser. L’examen anatomopathologique a confirmé la bénignité de la formation kystique dans les 2 cas.Mots-clés : Kyste de la vallécule, laryngoscopie directe, résection endoscopique, marsupialisation

Kyste hydatique cervico mediastinal a propos d’un cas

Le kyste hydatique cervico-médiastinal est extrêmement rare même en pays d’endémie. Il se manifeste généralement par une masse cervico-thoracique et il pose un problème délicat de diagnostic. Les auteurs rapportent le cas d’une femme de 53 ans, qui a consulté pour une masse sus claviculaire gauche évoluant depuis une année. Le bilan radiologique avait conclu au début à un magma d’adénopathies cervico-médiastinales. La patiente a bénéficié, alors, d’une cervicotomie exploratrice avec la découverte en per-opératoire d’un kyste hydatique cervico- médiastinal.Mots clé : Kyste hydatique, localisation cervico-médiastinale, imagerie

Genome Sequences of Two Tunisian Field Strains of Avian <I>Mycoplasma, M. meleagridis<I> and <I>M. gallinarum<I>

International audienceMycoplasma meleagridis and Mycoplasma gallinarum are bacteria that affect birds, but little is known about the genetic basis of their interaction with chickens and other poultry. Here, we sequenced the genomes of M. meleagridis strain MM_26B8_IPT and M. gallinarum strain Mgn_IPT, both isolated from chickens showing respiratory symptoms, poor growth, reduction in hatchability, and loss of production

The role of porcine reproductive and respiratory syndrome (PRRS) virus structural and non-structural proteins in virus pathogenesis

Porcine reproductive and respiratory syndrome (PRRS) is an economically devastating viral disease affecting the swine industry worldwide. The etiological agent, PRRS virus (PRRSV), possesses a RNA viral genome with nine open reading frames (ORFs). The ORF1a and ORF1b replicase-associated genes encode the polyproteins pp1a and pp1ab, respectively. The pp1a is processed in nine non-structural proteins (nsps): nsp1a, nsp1b, and nsp2 to nsp8. Proteolytic cleavage of pp1ab generates products nsp9 to nsp12. The proteolytic pp1a cleavage products process and cleave pp1a and pp1ab into nsp products. The nsp9 to nsp12 are involved in virus genome transcription and replication. The 30 end of the viral genome encodes four minor and three major structural proteins. The GP2a, GP3 and GP4 (encoded by ORF2a, 3 and 4), are glycosylated membrane associated minor structural proteins. The fourth minor structural protein, the E protein (encoded by ORF2b), is an unglycosylated membrane associated protein. The viral envelope contains two major structural proteins: a glycosylated major envelope protein GP5 (encoded by ORF5) and an unglycosylated membrane M protein (encoded by ORF6). The third major structural protein is the nucleocapsid N protein (encoded by ORF7). All PRRSV non-structural and structural proteins are essential for virus replication, and PRRSV infectivity is relatively intolerant to subtle changes within the structural proteins. PRRSV virulence is multigenic and resides in both the non-structural and structural viral proteins. This review discusses the molecular characteristics, biological and immunological functions of the PRRSV structural and nsps and their involvement in the virus pathogenesis

Escherichia coli Nissle 1917 Antagonizes Candida albicans Growth and Protects Intestinal Cells from C. albicans -Mediated Damage

Candida albicans is a pathobiont of the gastrointestinal tract. It can contribute to the diversity of the gut microbiome without causing harmful effects. When the immune system is compromised, C. albicans can damage intestinal cells and cause invasive disease. We hypothesize that a therapeutic approach against C. albicans infections can rely on the antimicrobial properties of probiotic bacteria. We investigated the impact of the probiotic strain Escherichia coli Nissle 1917 (EcN) on C. albicans growth and its ability to cause damage to intestinal cells. In co-culture kinetic assays, C. albicans abundance gradually decreased over time compared with C. albicans abundance in the absence of EcN. Quantification of C. albicans survival suggests that EcN exerts a fungicidal activity. Cell-free supernatants (CFS) collected from C. albicans -EcN co-culture mildly altered C. albicans growth, suggesting the involvement of an EcN-released compound. Using a model of co-culture in the presence of human intestinal epithelial cells, we further show that EcN prevents C. albicans from damaging enterocytes both distantly and through direct contact. Consistently, both C. albicans ’s filamentous growth and microcolony formation were altered by EcN. Taken together, our study proposes that probiotic-strain EcN can be exploited for future therapeutic approaches against C. albicans infections

Phylogenetic characterization of genes encoding for glycoprotein 5 and membrane protein of PRRSV isolate HH08

A porcine reproductive and respiratory syndrome virus (PRRSV) was obtained from clinic samples. Genes 5 and 6 encoding for the viral glycoprotein 5 and a membrane protein of the PRRSV designated as HH08 were amplified by reverse transcription-PCR. These sequences were compared with reference sequences derived from different geographical locations. The results indicated that the virus belongs to the North American type rather than European. Comparative analyses of the genetic diversity between the PRRSV isolate HH08 and other Chinese as well as foreign reference strains of PRRSV were discussed based on the sequence comparison and the topology of phylogenetic trees constructed in this study