296 resultados para Philology, Comparative


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BACKGROUND: The purpose of this study was to explore the potential use of image analysis on tissue sections preparation as a predictive marker of early malignant changes during squamous cell (SC) carcinogenesis in the esophagus. Results of DNA ploidy quantification on formalin-fixed, paraffin-embedded tissue using two different techniques were compared: imprint-cytospin and 6 microm thick tissue sections preparation. METHODS: This retrospective study included 26 surgical specimens of squamous cell carcinoma (SCC) from patients who underwent surgery alone at the Department of Surgery in CHUV Hospital in Lausanne between January 1993 and December 2000. We analyzed 53 samples of healthy tissue, 43 tumors and 7 lymph node metastases. RESULTS: Diploid DNA histogram patterns were observed in all histologically healthy tissues, either distant or proximal to the lesion. Aneuploidy was observed in 34 (79%) of 43 carcinomas, namely 24 (75%) of 32 early squamous cell carcinomas and 10 (91%) of 11 advanced carcinomas. DNA content was similar in the different tumor stages, whether patients presented with single or multiple synchronous tumors. All lymph node metastases had similar DNA content as their primary tumor. CONCLUSIONS: Early malignant changes in the esophagus are associated with alteration in DNA content, and aneuploidy tends to correlate with progression of invasive SCC. A very good correlation between imprint-cytospin and tissue section analysis was observed. Although each method used here showed advantages and disadvantages; tissue sections preparation provided useful information on aberrant cell-cycle regulation and helped select the optimal treatment for the individual patient along with consideration of other clinical parameters.

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Context: Both biallelic and monoallelic mutations in PROK2 or PROKR2 have been found in Kallmann syndrome (KS). Objective: The objective of the study was to compare the phenotypes of KS patients harboring monoallelic and biallelic mutations in these genes. Design and Patients: We studied clinical and endocrine features that reflect the functioning of the pituitary-gonadal axis, and the nonreproductive phenotype, in 55 adult KS patients (42 men and 13 women), of whom 41 had monoallelic mutations and 14 biallelic mutations in PROK2 or PROKR2. Results: Biallelic mutations were associated with more frequent cryptorchidism (70% vs. 34%, P < 0.05) and microphallus (90% vs. 28%, P < 0.001) and lower mean testicular volume (1.2 +/- 0.4 vs. 4.5 +/- 6.0 ml; P < 0.01) in male patients. Likewise, the testosterone level as well as the basal FSH level and peak LH level under GnRH-stimulation were lower in males with biallelic mutations (0.2 +/- 0.1 vs. 0.7 +/- 0.8 ng/ml; P = 0.05, 0.3 +/- 0.1 vs. 1.8 +/- 3.0 IU/liter; P < 0.05, and 0.8 +/- 0.8 vs. 5.2 +/- 5.5 IU/liter; P < 0.05, respectively). Nonreproductive, nonolfactory anomalies were rare in both sexes and were never found in patients with biallelic mutations. The mean body mass index of the patients (23.9 +/- 4.2 kg/m(2) in males and 26.3 +/- 6.6 kg/m(2) in females) did not differ significantly from that of gender-, age-, and treatment-matched KS individuals who did not carry a mutation in PROK2 or PROKR2. Finally, circadian cortisol levels evaluated in five patients, including one with biallelic PROKR2 mutations, were normal in all cases. Conclusion: Male patients carrying biallelic mutations in PROK2 or PROKR2 have a less variable and on average a more severe reproductive phenotype than patients carrying monoallelic mutations in these genes. Nonreproductive, nonolfactory clinical anomalies associated with KS seem to be restricted to patients with monoallelic mutations.

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Résumé A Madagascar, comme dans plusieurs pays en développement, une grande partie de la population utilise les plantes pour se soigner. Plusieurs espèces des plantes sont ainsi utilisées en médecine traditionnelle malgache. Par ailleurs, la plupart de ces plantes ne font l'objet que de très peu d'étude scientifique. En effet, dans le cadre de l'investigation phytochimique de plantes utilisées en médecine traditionnelle malgache et dans la recherche des nouvelles substances biologiquement actives, Hypoestes serpens (Vahl) R. Br. (Acanthaceae) a été étudiée. Elle se présente sous deux variétés (glabre et poilue) qui sont tous utilisées dans la région sud-centre de Madagascar pour traiter la blennorragie. De l'extrait dichlorométhanique des feuilles de H. serpens (Vahl) R. Br. variété glabre, 12 diterpénoides dont 8 nouveaux ont été isolés. Ils ont tous montré une activité antifongique contre un champignon pathogène des plantes, Cladosporium cucumerinum, dans la bioautographie directe sur CCM. Quelques-uns ont également présenté une activité contre une levure saprophyte chez l'homme, Candida albicans et une activité inhibitrice de l'enzyme acétylcholinesterase. Les diterpènoïdes sont déjà considérés comme les principaux métabolites secondaires du genre Hypoestes. Le fractionnement de l'extrait méthanolique a conduit à l'isolement de 5 glycosides des flavonoïdes dont 4 sous formes C-g,lycosides qui n'ont jamais été identifiés dans la famille Acanthaceae. Ces flavonoïdes ont présenté une activité antiradicalaire contre le DPPH. Le fractionnement et la purification des extraits ont été effectués à l'aide des différentes techniques chromatographiques telles que la chromatographie sur colonne ouverte, la filtration sur gel, la chromatographie liquide à haute pression, la chromatographie liquide à moyenne pression et la chromatographie liquide à basse pression. Par ailleurs, les structures des composés isolés ont été élucidées par des techniques spectroscopiques (UV, MS, RMN) et de méthode chimique (hydrolyse acide). En plus de ces techniques, certaines méthodes physiques (cristallographie par rayons-X, mesure de rotation optique) ont été réalisées pour confirmer certaines structures. Comme l'espèce Hypoestes serpens (Vahl) R. Br. se présente en deux variétés, une étude comparative a été effectuée. Cette étude avait montré que ces deux variétés ont une activité biologique similaire. Finalement, une technique analytique couplée, HPLC-UV-APC1-MS a permis de montrer la présence de toutes les substances isolées de la variété glabre dans la variété poilue. Second résumé Depuis des milliers d'almées, l'homme utilise les plantes pour se soigner. De nos jours, même avec le développement de la médecine moderne, la phytothérapie reste toujours la forme des soins de santé abordable et accessible pour la majorité des populations rurales des pays en développement. En outre, les plantes médicinales constituent une source potentielle de molécules biologiquement actives pour les industries pharmaceutiques et actuellement, on estime que 25% des médicaments commercialisés dans le monde sont à base de plantes Dans le cadre de la recherche des nouvelles molécules à intérêt thérapeutique qui pourraient devenir un médicament ou un modèle de structure ("lead compound") pour le développement de nouveaux médicaments, nous avons fait une étude sur l'espèce, Hypoestes serpens (Vahl) R. Br, plante utilisée en médecine traditionnelle malgache. Cette espèce existe en deux variétés, une glabre et une autre poilue qui sont tous utilisées dans la région sud-centre de Madagascar pour traiter la blennorragie. Par ailleurs, les tradipraticiens utilisent de préférence la variété poilue. Dans la première partie de ce présent travail, une investigation phytochimique de H serpens, variété glabre (variété moins utilisée) a d'abord été effectuée afm d'isoler et d'identifier le maximum des molécules biologiquement actives qu'elle contient. De ce fait, 17 composés dont 8 nouveaux ont été isolés. Les potentiels d'activités thérapeutiques des substances isolées ont ensuite été dépistés sur les différents cibles suivants.: deux souches de champignons (Cladosporium cucumerinum et Candida albicans), l'enzyme acétylcholinesterase et le radical DPPH. La deuxième partie de ce travail a été consacrée sur l'étude comparative des deux variétés (glabre et poilue) de H. serpens à la fois sur le plan biologique et sur le plan phytochimique. A l'issue de cette comparaison, nous avons constaté que l'utilisation de ces deux variétés en médecine traditionnelle malgache n'est pas un hasard ; les deux variétés avaient présenté une activité biologique très remarquable et contiennent les mêmes substances actives. Ces résultats démontrent les potentiels thérapeutiques de H serpens en médecine traditionnelle malgache et pourraient également encourager les tradipraticiens à utiliser la variété glabre tout en protégeant la variété poilue qui est en voie de disparition actuellement. En bref, l'investigation phytochimique de H. serpens justifiée par l'isolement et l'identification de certains de ses principes actifs ouvre la voie aux recherches des médicaments d'origine naturelle. Abstract In Madagascar, as in many developing countries, most people use plants to cure. A large number of plant species are employed in Malagasy traditional medicine. Moreover, most of these plants have been subject only very little scientific study. As part of a phytochemical investigation of plants used in Malagasy traditional medicine and in the search for new biologically active substances, Hypoestes serpens (Vah1) R.Br. (Acanthaceae) was investigated. This species exists in two varieties (glabrous and hairy) which are used in the south-center part of Madagascar to treat gonorrhoea. From the dichloromethane extract of the leaves of H. serpens (Vah1) R. Br. glabrous variety, 12 diterpenoids 8 of which were new, were isolated. They showed antifungal activity against the plant pathogen Cladosporium cucumerinum, in the direct TLC bioautography. Some of them also had activity against the yeast Candida athicans and inhibited acetylcholinesterase. The diterpenes are considered as the principal secondary metabolites of the genus Hypoestes. Fractionation of the methanol extract led to the isolation of 5 flavonoid glycosides, 4 of which were C-glycosides, never before identified in the Acanthaceae family. These flavonoids showed radical scavenging activity against DPPH. The fractionation and the purification of the extracts were achieved by different chromatographic techniques such as open-column chromatography, gel filtration, high- pressure liquid chromatography, medium-pressure liquid chromatography and low-pressure liquid chromatography. Moreover, the structures of the isolated compounds were elucidated by spectroscopic techniques (UV, MS, NMR) and chemical technique (acid hydrolysis). In addition, some physical methods (X-ray crystallography, measurement of optical rotation) were performed to confirm some structures. As the species Hypoestes serpens (Vah1) R. Br. is present in two varieties, a comparative study was carried out. This study showed that these two varieties had similar biological activity. Finally, a coupled analytical technique HPLC-UV-APCI-MS showed the presence of the same compounds in both the glabrous and hairy varieties.

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The aim of this study was to develop an ambulatory system for the three-dimensional (3D) knee kinematics evaluation, which can be used outside a laboratory during long-term monitoring. In order to show the efficacy of this ambulatory system, knee function was analysed using this system, after an anterior cruciate ligament (ACL) lesion, and after reconstructive surgery. The proposed system was composed of two 3D gyroscopes, fixed on the shank and on the thigh, and a portable data logger for signal recording. The measured parameters were the 3D mean range of motion (ROM) and the healthy knee was used as control. The precision of this system was first assessed using an ultrasound reference system. The repeatability was also estimated. A clinical study was then performed on five unilateral ACL-deficient men (range: 19-36 years) prior to, and a year after the surgery. The patients were evaluated with the IKDC score and the kinematics measurements were carried out on a 30 m walking trial. The precision in comparison with the reference system was 4.4 degrees , 2.7 degrees and 4.2 degrees for flexion-extension, internal-external rotation, and abduction-adduction, respectively. The repeatability of the results for the three directions was 0.8 degrees , 0.7 degrees and 1.8 degrees . The averaged ROM of the five patients' healthy knee were 70.1 degrees (standard deviation (SD) 5.8 degrees), 24.0 degrees (SD 3.0 degrees) and 12.0 degrees (SD 6.3 degrees for flexion-extension, internal-external rotation and abduction-adduction before surgery, and 76.5 degrees (SD 4.1 degrees), 21.7 degrees (SD 4.9 degrees) and 10.2 degrees (SD 4.6 degrees) 1 year following the reconstruction. The results for the pathologic knee were 64.5 degrees (SD 6.9 degrees), 20.6 degrees (SD 4.0 degrees) and 19.7 degrees (8.2 degrees) during the first evaluation, and 72.3 degrees (SD 2.4 degrees), 25.8 degrees (SD 6.4 degrees) and 12.4 degrees (SD 2.3 degrees) during the second one. The performance of the system enabled us to detect knee function modifications in the sagittal and transverse plane. Prior to the reconstruction, the ROM of the injured knee was lower in flexion-extension and internal-external rotation in comparison with the controlateral knee. One year after the surgery, four patients were classified normal (A) and one almost normal (B), according to the IKDC score, and changes in the kinematics of the five patients remained: lower flexion-extension ROM and higher internal-external rotation ROM in comparison with the controlateral knee. The 3D kinematics was changed after an ACL lesion and remained altered one year after the surgery

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High levels of HIV-1 replication during the chronic phase of infection usually correlate with rapid progression to severe immunodeficiency. However, a minority of highly viremic individuals remains asymptomatic and maintains high CD4+ T cell counts. This tolerant profile is poorly understood and reminiscent of the widely studied nonprogressive disease model of SIV infection in natural hosts. Here, we identify transcriptome differences between rapid progressors (RPs) and viremic nonprogressors (VNPs) and highlight several genes relevant for the understanding of HIV-1-induced immunosuppression. RPs were characterized by a specific transcriptome profile of CD4+ and CD8+ T cells similar to that observed in pathogenic SIV-infected rhesus macaques. In contrast, VNPs exhibited lower expression of interferon-stimulated genes and shared a common gene regulation profile with nonpathogenic SIV-infected sooty mangabeys. A short list of genes associated with VNP, including CASP1, CD38, LAG3, TNFSF13B, SOCS1, and EEF1D, showed significant correlation with time to disease progression when evaluated in an independent set of CD4+ T cell expression data. This work characterizes 2 minimally studied clinical patterns of progression to AIDS, whose analysis may inform our understanding of HIV pathogenesis.

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In specific and obligate interactions the nature and abundance of a given species can have important effects on the survival and population dynamics of associated organisms. In a phylogeographic framework, we therefore expect that the fates of organisms interacting specifically are also tightly interrelated. Here we investigate such a scenario by analyzing the genetic structures of species interacting in an obligate plant-insect pollination lure-and-trap antagonism, involving Arum maculatum (Araceae) and its specific psychodid (Diptera) visitors Psychoda phalaenoides and Psycha grisescens. Because the interaction is asymmetric (i.e., only the plant depends on the insect), we expect the genetic structure of the plant to be related with the historical pollinator availability, yielding incongruent phylogeographic patterns between the interacting organisms.Using insect mtDNA sequences and plant AFLP genome fingerprinting, we inferred the large-scale phylogeographies of each species and the distribution of genetic diversities throughout the sampled range, and evaluated the congruence in their respective genetic structures using hierarchical analyses of molecular variances (AMOVA). Because the composition of pollinator species varies in Europe, we also examined its association with the spatial genetic structure of the plant.Our findings indicate that while the plant presents a spatially well-defined genetic structure, this is not the case in the insects. Patterns of genetic diversities also show dissimilar distributions among the three interacting species. Phylogeographic histories of the plant and its pollinating insects are thus not congruent, a result that would indicate that plant and insect lineages do not share the same glacial and postglacial histories. However, the genetic structure of the plant can, at least partially, be explained by the type of pollinators available at a regional scale. Differences in life-history traits of available pollinators might therefore have influenced the genetic structure of the plant, the dependent organism, in this antagonistic interaction.

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Pseudomonas knackmussii B13 was the first strain to be isolated in 1974 that could degrade chlorinated aromatic hydrocarbons. This discovery was the prologue for subsequent characterization of numerous bacterial metabolic pathways, for genetic and biochemical studies, and which spurred ideas for pollutant bioremediation. In this study, we determined the complete genome sequence of B13 using next generation sequencing technologies and optical mapping. Genome annotation indicated that B13 has a variety of metabolic pathways for degrading monoaromatic hydrocarbons including chlorobenzoate, aminophenol, anthranilate and hydroxyquinol, but not polyaromatic compounds. Comparative genome analysis revealed that B13 is closest to Pseudomonas denitrificans and Pseudomonas aeruginosa. The B13 genome contains at least eight genomic islands [prophages and integrative conjugative elements (ICEs)], which were absent in closely related pseudomonads. We confirm that two ICEs are identical copies of the 103 kb self-transmissible element ICEclc that carries the genes for chlorocatechol metabolism. Comparison of ICEclc showed that it is composed of a variable and a 'core' region, which is very conserved among proteobacterial genomes, suggesting a widely distributed family of so far uncharacterized ICE. Resequencing of two spontaneous B13 mutants revealed a number of single nucleotide substitutions, as well as excision of a large 220 kb region and a prophage that drastically change the host metabolic capacity and survivability.

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La survie actuelle après correction chirurgicale de la Tétralogie de Fallot (TDF) est de 97% à 12 ans. Les principaux risques à long terme sont une régurgitation pulmonaire ou une sténose récidivante de la sortie droite du coeur, une tachycardie ventriculaire pouvant entrainer une mort subite. Le but de cette étude rétrospective est de comparer la correction chirurgicale de la TDF avec patch pulmonaire versus un conduit valvé xénogreffe. Le collectif se compose de 127 patients entre 2 mois et 16 ans, opérés pour une TDF entre l'année 2000 et 2010. La correction chirurgicale était soit avec un patch, soit avec un conduit valvé à la sortie droite. Cette étude montre d'une part qu'il n'y a pas de différence de survie à un mois entre les deux méthodes opératoires. De plus, elle montre que, lors de la pose d'un patch, il y a plus de sept fois plus d'insuffisances valvulaires modérées à sévères après un mois que lors de la pose d'un conduit valvé. D'autre part, elle démontre que la différence de gradient résiduel à la sortie droite entre la correction avec patch ou conduit n'est pas significative et que la valeur du gradient résiduel à la sortie droite en postopératoire n'est pas représentative du gradient résiduel à un mois. De plus, cette étude prouve que les coronaires aberrantes ainsi qu'un shunt palliatif de Blalock-Taussig sont des facteurs de risque indépendants pour une correction avec un conduit valvé.

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(241)Pu was determined in slurry samples from a nuclear reactor decommissioning project at the Paul Scherrer Institute (Switzerland). To validate the results, the (241)Pu activities of five samples were determined by LSC (TriCarb and Quantulus) and ICP-MS, with each instrument at a different laboratory. In lack of certified reference materials for (241)Pu, the methods were further validated using the (241)Pu information values of two reference sediments (IAEA-300 and IAEA-384). Excellent agreement with the results was found between LSC and ICP-MS in the nuclear waste slurries and the reference sediments.