Molecular Mechanics: The Conjugate Nitro Group Parameters in the MM2 Force Field

The conjugated nitro group has been included in the π system calculation within the MM2 force field. New parameters have been estimated by a statistical process from X-ray molecular structures recorded in the C.S.D.S. Comparison of the corresponding results with those given by the MM2(91) force field parameters show a clear improvement for dihedral and bond angles. For N-O and C-N bond lengths a slight global improvement is also observed. A closer examination of the results for the latter bond shows that sometimes MM2(91) gives better results for six membered ring nitro compounds. By contrast the parameters proposed here are more adapted to five membered ring derivatives. The derived linear relations permit the study of molecules over a wider range of π indices. The introduction of a correction factor to the calculated molecular π dipole moment in conjunction with a necessary reestimation of some σ-bond dipole moments also leads to improved total molecular dipole moments.     

Fruit damages caused by the broad-winged bush katydid,Scudderia pistillata (Orthoptera: Tettigoniidae) in commercial cranberry bog

In August 2018, unidentified damages were reported on cranberries in a conventional bog located in Quebec (Eastern Canada). Following a field inspection, high percentage of nibbled fruits as well as katydids (Orthoptera: Tettigoniidae) were observed. Several individuals (nymphs and adults) were seen feeding directly on the fruits. Specimens were captured and sent to the “Laboratoire d'expertise et de diagnostic en phytoprotection” of the “Quebec Ministry of Agriculture, Fisheries and Food" (LEDP-MAPAQ). They were identified as Scudderia pistillata Brunner von Wattenwyl (Orthoptera: Tettigoniidae). Subsequently, a systematic fruit sampling was realized into the beds where damages were observed to assess spatial patterns of infestation. To our knowledge, it constitutes the first mention of significant damages associated to this species in cranberry bogs and, in some cases, up to 5% damages to the fruits were observed. This observation suggests that S. pistillata represents a potential pest for this crop. Additionally, a decrease of damage rates was observed when distancing from the north-eastern corner of the bog. Hypothesis in regards of damages' spatial pattern is discussed.     

A Novel Set of Hepatic mRNAs Preferentially Expressed during an Acute Inflammation in Rat Represents Mostly Intracellular Proteins

A cloning of hepatic cDNAs associated with the early phase of an acute, systemic inflammation was carried out by differential screening of arrayed cDNA clones from rat livers obtained at 4-8 h postchallenge with Freund's complete adjuvant. End sequencing of 174 selected clones provided three cDNA groups that coded for: (i) 23 known acute-phase proteins, (ii) 31 known proteins whose change in hepatic synthesis during an acute phase was so far unsuspected, and (iii) 36 novel proteins whose cDNAs were completely sequenced. For 16 proteins in the third group the hepatic mRNA could be detected and quantitated by Northern blot hybridization in Freund's adjuvant-challenged animals, and an extrahepatic expression in healthy animals was further investigated. Matching the open reading frames of the 36 novel proteins with general and specialized data libraries indicated the potential relationships of 16 of these proteins with known protein families/superfamilies and/or the presence of functional domains previously described in other proteins. Overall, our search for novel inflammation-associated proteins selected mostly known or as yet undescribed proteins with an intracellular or membrane location, which extends our knowledge of the proteins involved in the intracellular metabolism of hepatic cells during a systemic, acute-phase response. Finally, some of the cDNAs above allowed us to successfully identify hepatic mRNAs that are differentially expressed in acute vs chronic (polyarthritis) inflammatory conditions in rat.     

Interet de la microinjection de spermatozoides sous la zone pellucide pour le traitement de certaines sterilites masculines

Sub-zonal insemination (SUZI) was evaluated, in a randomized prospective study, as a treatment for certain specific types of male factor infertility. Patients were classified according to the results of an extensive semen analysis as being either IVF failure with either normal or subnormal semen quality, specific (e.g. absent outer dynein arms) or non-specific flagellar dyskinesia, or oligoasthenoteratozoospermia. SUZI was found to be an efficient technique for achieving fertilization and pregnancy for all these indications, while there was a total failure of fertilization in the control, in-vitro inseminated oocytes. A total of 395 oocytes were microinjected and 133 fertilized, among which 75 (19% overall) were diploid. More than 81% of these zygotes cleaved normally, and 31 embryo transfers resulted in seven pregnancies. However, results varied widely between the various indications, suggesting that the underlying pathology responsible for the sterility may influence gamete interaction and early embryonic development independantly of the SUZI technique.     

Une cellule endocrine au cœur du métabolisme: l’adipocyte

Ces quelques exemples montrent bien l’importance que peut jouer le tissu adipeux dans la régulation de l’homéostasie glucidique et lipidique chez l’homme.Ses produits de sécrétions peuvent être bénéfiques (adiponectine) ou délétères quand ils sont produits en excès (IL-6 et TNFα). La localisation des dép?ts de tissu adipeux est aussi importante puisque, à degré d’obésité égal, l’excès de graisse viscérale est associé à une morbidité plus importante. Enfin, il ne faut pas oublier que si nous ne sommes pas tous égaux en ce qui concerne la surcharge pondérale, nous ne le sommes pas non plus en ce qui concerne la répartition des graisses puisque ces deux composants sont sous le contr?le de facteurs génétiques.     

Expression of S100B during embryonic development of the mouse cerebellum

Background  

In the cerebellum of newborn S100B-EGFP mice, we had previously noted the presence of a large population of S100B-expressing cells, which we assumed to be immature Bergmann glial cells. In the present study, we have drawn on this observation to establish the precise spatio-temporal pattern of S100B gene expression in the embryonic cerebellum.     

ComorbiditéS associées au trouble déficit de l’attention avec hyperactivité : Données épidémiologiques et implications thérapeutiques

ADHD has become one of the most frequent cause of referrals for children’ behaviour disorders. ADHD is a prevalent psychiatric condition affecting 5% to 9% of school-age children with regards to DSM-IV R diagnostic criteria. In addition, according to the results of different epidemiological studies, patients with ADHD very often experience comorbid conditions in 50% to 90% of the cases. The most frequent comorbidities include externalised disorders, (oppositional defiant disorder, conduct disorders), learning disorders, internalised disorders (anxiety, depression) and tics (chronic motor tics, Tourette’s syndrome). Given their negative impact on the outcome of ADHD in terms of affective and social functioning, and of social and school adaptation, these comorbid conditions should be carefully and systematically searched, even without any actual complaint. Although management of comorbid psychiatric conditions is never simple nor straightforward, therapeutic option should be considered taking into consideration both management of ADHD and specificity of these comorbidities.