A Bilateral Dysgerminoma: A Rare Presentation of the Swyer Syndrome

peer reviewedSwyer syndrome is a pure gonad dysgenesis associating 46 XY karyotype, primary amenorrhea, presence of female internal genital tract and bilateral streak gonads in a phenotypic female. The diagnosis is usually made at adolescence when the primary amenorrhea is investigated. We report the case of a 25-year-old XY woman who developed a bilateral dysgerminoma from undifferentiated gonads

High-resolution neutron and X-ray diffraction room-temperature studies of an H-FABP-oleic acid complex: study of the internal water cluster and ligand binding by a transferred multipolar electron-density distribution

Crystal diffraction data of heart fatty acid binding protein (H-FABP) in complex with oleic acid were measured at room temperature with high-resolution X-ray and neutron protein crystallography (0.98 and 1.90 Å resolution, respectively). These data provided very detailed information about the cluster of water molecules and the bound oleic acid in the H-FABP large internal cavity. The jointly refined X-ray/neutron structure of H-FABP was complemented by a transferred multipolar electron-density distribution using the parameters of the ELMAMII library. The resulting electron density allowed a precise determination of the electrostatic potential in the fatty acid (FA) binding pocket. Bader's quantum theory of atoms in molecules was then used to study interactions involving the internal water molecules, the FA and the protein. This approach showed H···H contacts of the FA with highly conserved hydrophobic residues known to play a role in the stabilization of long-chain FAs in the binding cavity. The determination of water hydrogen (deuterium) positions allowed the analysis of the orientation and electrostatic properties of the water molecules in the very ordered cluster. As a result, a significant alignment of the permanent dipoles of the water molecules with the protein electrostatic field was observed. This can be related to the dielectric properties of hydration layers around proteins, where the shielding of electrostatic interactions depends directly on the rotational degrees of freedom of the water molecules in the interface.Facultad de Ciencias ExactasInstituto de Física de Líquidos y Sistemas Biológico

High-resolution neutron and X-ray diffraction room-temperature studies of an H-FABP-oleic acid complex: study of the internal water cluster and ligand binding by a transferred multipolar electron-density distribution

Crystal diffraction data of heart fatty acid binding protein (H-FABP) in complex with oleic acid were measured at room temperature with high-resolution X-ray and neutron protein crystallography (0.98 and 1.90 Å resolution, respectively). These data provided very detailed information about the cluster of water molecules and the bound oleic acid in the H-FABP large internal cavity. The jointly refined X-ray/neutron structure of H-FABP was complemented by a transferred multipolar electron-density distribution using the parameters of the ELMAMII library. The resulting electron density allowed a precise determination of the electrostatic potential in the fatty acid (FA) binding pocket. Bader's quantum theory of atoms in molecules was then used to study interactions involving the internal water molecules, the FA and the protein. This approach showed H···H contacts of the FA with highly conserved hydrophobic residues known to play a role in the stabilization of long-chain FAs in the binding cavity. The determination of water hydrogen (deuterium) positions allowed the analysis of the orientation and electrostatic properties of the water molecules in the very ordered cluster. As a result, a significant alignment of the permanent dipoles of the water molecules with the protein electrostatic field was observed. This can be related to the dielectric properties of hydration layers around proteins, where the shielding of electrostatic interactions depends directly on the rotational degrees of freedom of the water molecules in the interface.Facultad de Ciencias ExactasInstituto de Física de Líquidos y Sistemas Biológico

Editorial: Observational studies in ADHD: the effects of switching to modified-release methylphenidate preparations on clinical outcomes and adherence

Patients with ADHD may have better adherence to treatment with modified-release methylphenidate (MPH-MR) formulations, which are taken once daily, compared with immediate-release (IR) formulations, which need to be taken several times a day. Data on long-term outcomes such as adherence may be lacking from randomised controlled trials as these are usually only short-term. Observational studies, if performed and reported appropriately, can provide valuable long-term data on such outcomes, as well as additional information on effectiveness and efficiency, from a real-life setting. By reviewing previous observational studies that have investigated switching treatment from MPH-IR to MPH-MR, results from a new, naturalistic observational study, the OBSEER study, are put into context. We conclude that, based on observational trial data, switching from MPH-IR to MPH-MR is a valid clinical approach, with the potential for improved clinical outcome and treatment adherence

Active Trachoma among Children in Mali: Clustering and Environmental Risk Factors

Active trachoma is not uniformly distributed in endemic areas, and local environmental factors influencing its prevalence are not yet adequately understood. Determining whether clustering is a consistent phenomenon may help predict likely modes of transmission and help to determine the appropriate level at which to target control interventions. In this work, we estimated the magnitude of clustering at different levels and investigated the influence of socio-economic factors and environmental features on active trachoma prevalence among children in Mali (1996–1997 nationwide survey). Clustering revealed significant results at the child, caretaker, household, and village levels. Moreover, beyond some well-established individual risk factors (age between 3 and 5, dirty face, and flies on the face), we found that temperature, sunshine fraction, and presence of rainy days were negatively associated with active trachoma prevalence. This study clearly indicates the importance of directing control efforts both at children with active trachoma as well as those with close contact, and at communities. These results support facial cleanliness and environmental improvements as population-health initiatives to combat blinding trachoma

R&ocirc;le de la chalcone synthase dans la biosynth&egrave;se des flavono&iuml;des au cours de la croissance annuelle des pousses de noyers hybrides (<em>Juglans nigra &times; Juglans regia)</em> adultes et rajeunis. Applications &agrave; l&#39;enracineme

Au cours de la croissance des pousses annuelles de noyer hybride (Juglans nigra &times; Juglans regia), le rajeunissement est marqu&eacute; par une augmentation de la teneur en hydrojuglone glucoside (naphtoquinone) en d&eacute;but de croissance et une diminution de celle en myricitrine (flavonol) en fin de croissance. Ces modifications sont particuli&egrave;rement nettes dans la moelle l&#39;ann&eacute;e du rec&eacute;page, dans le phlo&egrave;me et &agrave; un degr&eacute; moindre dans l&#39;&eacute;corce l&#39;ann&eacute;e suivante. La pr&eacute;paration de la chalcone synthase du noyer (premi&egrave;re enzyme de la voie de biosynth&egrave;se des flavono&iuml;des) a n&eacute;cessit&eacute; l&#39;utilisation d&#39;acide ascorbique &agrave; forte concentration afin d&#39;obtenir &agrave; pH 6,8 une r&eacute;action compl&egrave;te, stable et reproductible. Par ailleurs, nous avons pu montrer l&#39;inhibition de la chalcone synthase par la c&eacute;rul&eacute;nine et les produits de la r&eacute;action et la non-inhibition par les flavonols. Une relation entre l&#39;activit&eacute; chalcone synthase et l&#39;accumulation des principaux flavono&iuml;des du noyer a &eacute;t&eacute; mise en &eacute;vidence au niveau de la pousse enti&egrave;re et plus pr&eacute;cis&eacute;ment de l&#39;ensemble des tissus &laquo;&eacute;corce et phlo&egrave;me&raquo;. L&#39;activit&eacute; chalcone synthase des pousses de noyer cultiv&eacute;es in vitro a &eacute;t&eacute; modul&eacute;e par des apports exog&egrave;nes et par l&#39;expression du g&egrave;ne chalcone synthase antisens. En culture in vitro, nous avons ainsi pu montrer une relation entre un relentissement du m&eacute;tabolisme des flavono&iuml;des et une augmentation de l&#39;aptitude &agrave; l&#39;enracinement. Les r&eacute;sultats obtenus &agrave; partir de pousses transform&eacute;es par le g&egrave;ne chalcone synthase antisens nous conduisent &agrave; &eacute;tudier la r&eacute;gulation de l&#39;expression du g&egrave;ne chalcone synthase antisens en particulier au niveau du phlo&egrave;m

Rupture prématurée des membranes dans les grossesses multiples. Extraction active échoguidée du foetus et poursuite de la grossesse. A propos de deux cas.

Late miscarriage is a well-known complication in multiple pregnancies. Two cases were presented with rupture of the membranes and prolapse of the cord with the death of the presenting fetus are reported. In both cases extraction of the presenting fetus was carried out at 21 weeks of pregnancy followed by cervical cerclage. A triplet pregnancy which was reduced to two fetuses reached 30 weeks and two healthy infants were delivered. A twin pregnancy which was reduced to one fetus, resulted in that one being lost two weeks later when the patient developed chorioamnionitis and septicaemia