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Intestinal absorption of macromolecules during viral enteritis: an experimental study on rotavirus-infected conventional and germ-free mice.
Epithelial transport and degradation of horseradish peroxidase (HRP), a macromolecular tracer, was studied in conventional and germ-free suckling mice following an experimental infection with rotavirus. Conventional and germ-free mice developed diarrhea from days 2 to 8 postinfection (pi), with growth failure. In mucosal homogenates, infectious virus detected by immunofluorescence on MA 104 cells was present from day 2 through day 8 pi in germ-free mice, but persisted longer (day 13 pi) in conventional mice. Only mild histological lesions were observed during diarrhea, but obvious macrovacuolation of epithelial cells and increased cellular density occurred during the convalescence period (days 9 to 13 pi). Intact and degraded HRP fluxes from mucosa to serosa were measured in vitro on segments of jejunum mounted in Ussing chambers. Both groups of mice developed increased HRP permeability during the experimental period, but at different times after inoculation: during the diarrheal period (days 2 and 3 pi) conventional mouse epithelium absorbed five times more HRP than noninfected controls and during the convalescence period (days 9 to 13 pi) HRP absorption in germ-free mice rose 10-fold as compared to its level before infection. In both cases, this increase in HRP permeability was entirely due to an increase in intact HRP absorption, probably via a transcellular route, and occurred without any alteration in degraded HRP transport. These results indicate that in mice, rotavirus infection causes a transient rise in gut permeability to undegraded proteins. The intestinal microflora seems to affect the timing, magnitude, and duration of this increased permeability
Age and growth of Distichodus antonii (Schilthuis, 1891) (Pisces, Teleostei, Distichontidae) in Pool Malebo, Congo River
The estimation of demographic parameters of Distichodus antonii, in Pool Malebo (Congo River), was obtained from analysis of 36 good scales samples. L‡ was estimated at 107.91 cm, K at 0.10 .year-1 and t0 at -0.67 year-1. The growth parameters calculated from this method revealed that this fish has a slow growth rate and it reaches a large size. The analysis of marginal increase shows that the formation of annulus takes place to the dry season. During the dry season, the environmental conditions are
disturbed and the access to food becomes difficult. This is probably the base of the stress that induces the formation of annuli on the scales
Profil épidémiologique et prise en charge de l’éclampsie au Sénégal: À propos de 62 cas
Introduction: L'objectif de cette étude etait d'apprécier les caractéristiques épidémiologiques et cliniques de l'éclampsie et d'évaluer la prise encharge et le pronostic maternel et périnatal.Méthodes: étude descriptive rétrospective sur 3 années (2007-2010) dans un service de Gynécologie Obstétrique de Dakar (Sénégal). Le critère d'inclusion était toute crise convulsive en période gravido-puerpérale dans un contexte de prééclampsie.Résultats: sur un total de 4587 accouchements, 62 cas d'éclampsie étaient enregistrés représentant une incidence de 1,35%. Le profil retrouvéétait celui d'une jeune femme (24 ans), primipare (58.1%), habitant la banlieue dakaroise (83.8%), porteuse d'une grossesse à terme (56.5%),mal suivie (82.3%) et référée par un poste de santé environnant (82.3%). La crise était survenue en antépartum et en post-partum dans 72.5 et 27,5% respectivement. Toutes les patientes présentaient une HTA ; l''dème et la protéinurie étaient retrouvés dans 72.5 et 84% respectivement. La majorité des patientes (88%) avait présenté plus de deux crises et l'état de mal éclamptique concernait 14.5% des cas. Le sulfate de magnésium était utilisé chez toutes les patientes. La césarienne était le mode d'accouchement largement adopté (75.5%) pour les patientes reçues en antépartum. Le pronostic maternel était marqué par un cas de décès. La mortalité périnatale était de 130%. Conclusion: L'éclampsie est un problème de santé publique dans les pays en développement. Les principaux facteurs de risque sont la primiparité et l'âge jeûne. L'administration du sulfate de magnésium et la césarienne permettent d'améliorer le pronostic maternel et foetal. La prévention passe nécessairement par un suivi prénatal de qualité
Accouchement de jumeaux conjoints de découverte fortuite au cours du travail au CHU de Dakar
L’objectif de cette étude était de rapporter 3 cas de jumeaux conjoints, discuter de l’importance du diagnostic anténatal et de décrire les particularités diagnostiques, thérapeutiques et évolutives. Sur 45700 accouchements du 1er Février 2009 au 31 Décembre 2011, 3 cas de jumeaux conjoints ont été enregistrés, soit 1 cas pour 15000 accouchements. Ces cas ont été diagnostiqués au cours du travail au décours d’une dystocie mécanique ou d’une césarienne réalisée pour une autre indication. Il s’agissait d’un cas de jumeaux conjoints thoraco-omphalopages, un cas de diprosopes et un cas de dicéphales. L’accouchement dans les trois cas était fait par voie haute permettant d’extraire des mort-nés frais. Nous insistons sur l’intérêt d’un diagnostic anténatal précoce par le recours à l’échographie afin d’éviter les accidents mécaniques d’un accouchement qui ne saurait s’accomplir par voie basse.Key words: Jumeaux conjoints, diprosopes, dicéphales, thoraco-omphalopage
Are bisphosphonates effective in the treatment of osteoarthritis pain? A meta-analysis and systematic review.
Osteoarthritis (OA) is the most common form of arthritis worldwide. Pain and reduced function are the main symptoms in this prevalent disease. There are currently no treatments for OA that modify disease progression; therefore analgesic drugs and joint replacement for larger joints are the standard of care. In light of several recent studies reporting the use of bisphosphonates for OA treatment, our work aimed to evaluate published literature to assess the effectiveness of bisphosphonates in OA treatment
Plasmonically Enhanced Reflectance of Heat Radiation from Low-Bandgap Semiconductor Microinclusions
Increased reflectance from the inclusion of highly scattering particles at
low volume fractions in an insulating dielectric offers a promising way to
reduce radiative thermal losses at high temperatures. Here, we investigate
plasmonic resonance driven enhanced scattering from microinclusions of
low-bandgap semiconductors (InP, Si, Ge, PbS, InAs and Te) in an insulating
composite to tailor its infrared reflectance for minimizing thermal losses from
radiative transfer. To this end, we compute the spectral properties of the
microcomposites using Monte Carlo modeling and compare them with results from
Fresnel equations. The role of particle size-dependent Mie scattering and
absorption efficiencies, and, scattering anisotropy are studied to identify the
optimal microinclusion size and material parameters for maximizing the
reflectance of the thermal radiation. For composites with Si and Ge
microinclusions we obtain reflectance efficiencies of 57 - 65% for the incident
blackbody radiation from sources at temperatures in the range 400 - 1600
{\deg}C. Furthermore, we observe a broadbanding of the reflectance spectra from
the plasmonic resonances due to charge carriers generated from defect states
within the semiconductor bandgap. Our results thus open up the possibility of
developing efficient high-temperature thermal insulators through use of the
low-bandgap semiconductor microinclusions in insulating dielectrics.Comment: Main article (8 Figures and 2 Tables) + Supporting Information (8
Figures
The Molecular Clockwork of the Fire Ant Solenopsis invicta
This is an open-access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication
The metabolic basis of adolescent idiopathic scoliosis: 2011 report of the “metabolic” workgroup of the Fondation Yves Cotrel
OBJECTIVE: The purpose of this review is to elucidate the metabolic processes involved in the pathogenesis of adolescent idiopathic scoliosis (AIS) in light of research by the present authors as well as current literature. METHODS: Pathogenetic mechanism
DNA resection in eukaryotes: deciding how to fix the break
DNA double-strand breaks are repaired by different mechanisms, including homologous
recombination and nonhomologous end-joining. DNA-end resection, the first step in
recombination, is a key step that contributes to the choice of DSB repair. Resection, an
evolutionarily conserved process that generates single-stranded DNA, is linked to checkpoint
activation and is critical for survival. Failure to regulate and execute this process results in
defective recombination and can contribute to human disease. Here, I review recent findings on
the mechanisms of resection in eukaryotes, from yeast to vertebrates, provide insights into the
regulatory strategies that control it, and highlight the consequences of both its impairment and its
deregulation
Karyotype, Sex Determination, and Meiotic Chromosome Behavior in Two Pholcid (Araneomorphae, Pholcidae) Spiders: Implications for Karyotype Evolution
There are 1,111 species of pholcid spiders, of which less than 2% have published karyotypes. Our aim in this study was to determine the karyotypes and sex determination mechanisms of two species of pholcids: Physocyclus mexicanus (Banks, 1898) and Holocnemus pluchei (Scopoli, 1763), and to observe sex chromosome behavior during meiosis. We constructed karyotypes for P. mexicanus and H. pluchei using information from both living and fixed cells. We found that P. mexicanus has a chromosome number of 2n = 15 in males and 2n = 16 in females with X0-XX sex determination, like other members of the genus Physocyclus. H. pluchei has a chromosome number of 2n = 28 in males and 2n = 28 in females with XY-XX sex determination, which is substantially different from its closest relatives. These data contribute to our knowledge of the evolution of this large and geographically ubiquitous family, and are the first evidence of XY-XX sex determination in pholcids
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