Présentation clinique et investigations adéquates pour torsion ovarienne chez l’enfant et l’adolescente

Background : la torsion ovarienne est une pathologie rare et difficile à diagnostiquer en raison du manque de spécificité de la présentation clinique, des examens complémentaires et de l’imagerie. Cela entraîne un retard diagnostic, potentiellement menaçant pour la survie de l’ovaire. A ce jour, il n’existe pas de guidelines pour les torsions ovariennes. Objectif : l’objectif de ce travail est de comparer les données de la littérature et celles récoltées rétrospectivement au CHUV (Centre hospitalier universitaire vaudois) concernant la prise en charge des torsions ovariennes chez l’enfant et l’adolescente. L’analyse qui en découle devrait pouvoir servir de base à une large étude prospective romande ou nationale afin d’établir un algorithme de prise en charge lors de suspicion clinique de torsion d’ovaire. Méthode : une revue de littérature a été établie afin de servir de comparatif à l’étude descriptive rétrospective menée dans ce travail, comptant dix-sept patientes (pour dix-huit torsions). Une fois les résultats obtenus, une analyse descriptive de la prise en charge des torsions ovariennes a été effectuée et les résultats comparés à la littérature. Résultats : l’âge médian des patientes est de 8,9 ans, la plupart manifestant des douleurs subites ou intermittentes en fosse iliaque droite, souvent associées à des nausées et/ou des vomissements. A l’examen clinique, une douleur à la palpation de l’abdomen est le signe le plus souvent retrouvé. Le principal diagnostic différentiel évoqué lors de cette présentation clinique est l’appendicite, suivie de la torsion ovarienne. Les examens de laboratoire ne sont que peu utiles au diagnostic. L’écho-Doppler, imagerie de choix, montre souvent une augmentation du volume de l’ovaire et la présence d’un kyste associé ou non à une masse. Le CT, l’IRM et l’ASP ne sont que rarement utilisés dans ce contexte. Le délai diagnostic est de 16 heures. Le traitement, par laparoscopie le plus souvent, est soit une conservation de l’ovaire, soit son ablation. Sur toute la durée de notre étude, deux torsions ont récidivé. Conclusion : la prise en charge des torsions ovariennes au CHUV est globalement la même que celle décrite dans la littérature, mais le traitement pourrait davantage être conservateur. Par manque de spécificité de la présentation clinique, le diagnostic de torsion ovarienne n’est pas évoqué dans près de la moitié des cas. L’examen de choix est l’écho- Doppler, mais la présence de flux n’exclut pas une torsion ovarienne. Le faible délai de prise en charge chirurgicale est le reflet d’une bonne prise en charge globale des torsions ovariennes à Lausanne. Une étude prospective à large échelle pourrait permettre la réduction de ce délai par le biais d’une mise en place d’un algorithme de prise en charge

Tunicate cytostatic factor TC14-3 induces a polycomb group gene and histone modification through Ca2+ binding and protein dimerization

<p>Abstract</p> <p>Background</p> <p>As many invertebrate species have multipotent cells that undergo cell growth and differentiation during regeneration and budding, many unique and interesting homeostatic factors are expected to exist in those animals. However, our understanding of such factors and global mechanisms remains very poor. Single zooids of the tunicate, <it>Polyandrocarpa </it><it>misakiensis</it>, can give off as many as 40 buds during the life span. Bud development proceeds by means of transdifferentiation of very limited number of cells and tissues. TC14-3 is one of several different but closely related polypeptides isolated from <it>P. misakiensis</it>. It acts as a cytostatic factor that regulates proliferation, adhesion, and differentiation of multipotent cells, although the molecular mechanism remains uncertain. The Polycomb group (PcG) genes are involved in epigenetic control of genomic activity in mammals. In invertebrates except <it>Drosophila</it>, PcG and histone methylation have not been studied so extensively, and genome-wide gene regulation is poorly understood.</p> <p>Results</p> <p>When Phe⁶⁵of TC14-3 was mutated to an acidic amino acid, the resultant mutant protein failed to dimerize. The replacement of Thr⁶⁹with Arg⁶⁹made dimers unstable. When Glu¹⁰⁶was changed to Gly¹⁰⁶, the resultant mutant protein completely lost Ca²⁺binding. All these mutant proteins lacked cytostatic activity, indicating the requirement of protein dimerization and calcium for the activity. <it>Polyandrocarpa </it><it>Eed</it>, a component of PcG, is highly expressed during budding, like TC14-3. When wild-type and mutant TC14-3s were applied in vivo and in vitro to <it>Polyandrocarpa </it>cells, only wild-type TC14-3 could induce <it>Eed </it>without affecting histone methyltransferase gene expression. Eed-expressing cells underwent trimethylation of histone H3 lysine27. <it>PmEed </it>knockdown by RNA interference rescued cultured cells from the growth-inhibitory effects of TC14-3.</p> <p>Conclusion</p> <p>These results show that in <it>P. misakiensis</it>, the cytostatic activity of TC14-3 is mediated by <it>PmEed </it>and resultant histone modification, and that the gene expression requires both the protein dimerization and Ca²⁺-binding of TC14-3. This system consisting of a humoral factor, PcG, and histone methylation would contribute to the homeostatic regulation of cell growth and terminal differentiation of invertebrate multipotent cells.</p

Impact of the COVID-19 pandemic on the severity and management of acute appendicitis.

The literature seems to indicate that the number of appendectomies dropped at the beginning of the coronavirus disease in 2019 (COVID-19 pandemic), while the number of complicated appendicitis increased due to late presentation. In addition, a longer delay before surgical treatment resulted in a higher morbidity. This study aims to compare the number of appendectomies, the severity, and the management of acute appendicitis during the first two pandemic peaks of COVID-19 with those observed during the same seasonal periods in the previous 2 years in a regional hospital in Switzerland. We retrospectively reviewed and compared the number of appendectomies, rate of complicated appendicitis, delay to consultation and to surgery, distribution of appendectomies over a 24-h schedule, postoperative outcomes, and rates of overall complications in 177 patients, that is, 66 during the COVID-19 pandemic and 111 before the pandemic. No statistical difference was found in the number of appendectomies, duration of symptoms before consultation, median time to surgery, number of appendectomies performed outside the usual scheduled time for non-urgent surgery, length of postoperative stay, or the rates of overall complications. However, there was a trend in the rate of complicated appendicitis (p = .05). In spite of a high incidence rate of COVID-19 in our canton, the impact of COVID-19 on our population did not follow the pattern observed elsewhere. The reasons for this might be that people would still present to the emergency department due to less strict social distancing measures. Great availability of emergency operating room may also account for the unchanged delay preceding surgical treatment and complication rates

The Ligand-Binding Loops in the Tunicate C-type Lectin TC14 are Rigid

C-type lectin-like domains are very common components of extracellular proteins in animals. They bind to a variety of ligands, including carbohydrates, proteins, ice, and CaCO3 crystals. Their structure is characterized by long surface loops in the area of the protein usually involved in ligand binding. The C-type lectin TC14 from Polyandrocarpa misakiensis specifically binds to D-galactose by coordination of the sugar to a bound calcium atom. We have studied the dynamic properties of TC14 by measuring 15N longitudinal and transverse relaxation rates as well as [1H-15N] heteronuclear NOEs. Relaxation rates and heteronuclear NOE data for holo-TC14 show minimal variations, indicating that there is no substantial difference in rigidity between the elements of regular secondary structure and the extended surface loops. Anisotropic tumbling of the elongated TC14 dimer can account for the main fluctuations in relaxation rates. Loss of the bound calcium does not significantly alter the internal dynamics, suggesting that the stability of the loop region is intrinsic and not dependent on the coordination of the calcium ion. Chemical shift differences between the holo and apo form show that main structural changes occur in the calcium-binding site, but smaller structural changes are propagated throughout the molecule without affecting the overall fold. The disappearance of two resonances for residues following the conserved cis-proline 87 (which is located in the calcium-binding site) in the apo form indicates conformational change on an NMR time scale between the cis and trans configurations of this peptide bond in the absence of calcium. Possible implications of these findings for the ligand binding in C-type lectin-like domains are discussed

Lymphatic malformations in children: retrospective review of surgical and interventional management.

Lymphatic malformations (LMs) are classified as macrocystic, microcystic or mixed. Treatment depends on their characteristics: surgery, sclerotherapy, both combined, systemic treatment or observation. This study aims to analyze the surgical and interventional management of LMs in children over the last two decades in our university hospital. Management of children born with LMs between 2000 and 2019 was reviewed. Parameters collected were: malformation characteristics, type of treatment, symptoms, imaging, timing of diagnosis and first treatment, number of interventions, recovery rate, complications and length of stay. Files of 48 children were reviewed: 27 with macrocystic and 21 with microcystic LMs. There was no statistically significant difference in type of treatment except for combined treatment, more performed in microcystic LMs (p = 0.04). Symptoms, imaging, timing of diagnosis and first treatment, number of interventions and complications were not statistically significant. Overall, the number of surgeries was lower than sclerotherapies (p = 0.04). Recovery rate after surgery was higher in macrocystic LMs (p = 0.01). Complications and length of stay were not statistically significant. A good rate of recovery was observed when surgery was performed, with no significant increase in complications and length of stay. A prospective study will be determinant to create a decisional algorithm for children with LMs