996 resultados para CCD(Charge Coupled Device)
Resumo:
Vertebral osteoporotic fracture (VOF) is a major problem of public health. Surgical treatments such as vertebroplasty and kyphoplasty are interesting adjuvant treatments for the management of osteoporosis. A consensus proposed by the principal contributors of this management is important. Regarding the actual data, we propose a vertebroplasty or a kyphoplasty for all patients suffering of an acute VOF. If a previous kyphosis or an important local kyphosis exists, secondary to the acute VOF or others, we propose a kyphoplasty. If the VOF is older and the conservative treatment is inefficient, we propose a vertebroplasty. In all cases, a specific management and treatment of osteoporosis is proposed.
Resumo:
Lower limbs superficial venous thrombosis (SVT) is a relatively frequent disease. Its prevalence among patients consulting their treating physician is estimated to be 10.8% among women and 4.9% among men. Up to 25% of at risk patients with isolated SVT present with a concomitant DVT. Ultrasound imaging may play a role in the management of these patients allowing precise diagnosis, determination of thrombus extension and presence of associated DVT. From data recently appeared in the literature treatment of SVT with prophylactic doses of fondaparinux may be proposed to at risk patients with isolated SVT.
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The aim of a large number of studies on G protein-coupled receptors was centered on understanding the structural basis of their main functional properties. Here, we will briefly review the results obtained on the alpha1-adrenergic receptor subtypes belonging to the rhodopsin-like family of receptors. These findings contribute, on the one hand, to further understand the molecular basis of adrenergic transmission and, on the other, to provide some generalities on the structure-functional relationship of G protein-coupled receptors.
Resumo:
Catecholamines as well as phorbol esters can induce the phosphorylation and desensitization of the alpha1B-adrenergic receptor (alpha1BAR). In this study, phosphoamino acid analysis of the phosphorylated alpha1BAR revealed that both epinephrine- and phorbol ester-induced phosphorylation predominantly occurs at serine residues of the receptor. The findings obtained with receptor mutants in which portions of the C-tail were truncated or deleted indicated that a region of 21 amino acids (393-413) of the carboxyl terminus including seven serines contains the main phosphorylation sites involved in agonist- as well as phorbol ester-induced phosphorylation and desensitization of the alpha1BAR. To identify the serines invoved in agonist- versus phorbol ester-dependent regulation of the receptor, two different strategies were adopted, the seven serines were either substituted with alanine or reintroduced into a mutant lacking all of them. Our findings indicate that Ser394 and Ser400 were phosphorylated following phorbol ester-induced activation of protein kinase C, whereas Ser404, Ser408, and Ser410 were phosphorylated upon stimulation of the alpha1BAR with epinephrine. The observation that overexpression of G protein-coupled kinase 2 (GRK2) could increase agonist-induced phosphorylation of Ser404, Ser408, and Ser410, strongly suggests that these serines are the phosphorylation sites of the alpha1BAR for kinases of the GRK family. Phorbol ester-induced phosphorylation of the Ser394 and Ser400 as well as GRK2-mediated phosphorylation of the Ser404, Ser408, and Ser410, resulted in the desensitization of alpha1BAR-mediated inositol phosphate response. This study provides generalities about the biochemical mechanisms underlying homologous and heterologous desensitization of G protein-coupled receptors linked to the activation of phospholipase C.
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Genotype-based algorithms are valuable tools for the identification of patients eligible for CCR5 inhibitors administration in clinical practice. Among the available methods, geno2pheno[coreceptor] (G2P) is the most used online tool for tropism prediction. This study was conceived to assess if the combination of G2P prediction with V3 peptide net charge (NC) value could improve the accuracy of tropism prediction. A total of 172 V3 bulk sequences from 143 patients were analyzed by G2P and NC values. A phenotypic assay was performed by cloning the complete env gene and tropism determination was assessed on U87_CCR5(+)/CXCR4(+) cells. Sequences were stratified according to the agreement between NC values and G2P results. Of sequences predicted as X4 by G2P, 61% showed NC values higher than 5; similarly, 76% of sequences predicted as R5 by G2P had NC values below 4. Sequences with NC values between 4 and 5 were associated with different G2P predictions: 65% of samples were predicted as R5-tropic and 35% of sequences as X4-tropic. Sequences identified as X4 by NC value had at least one positive residue at positions known to be involved in tropism prediction and positive residues in position 32. These data supported the hypothesis that NC values between 4 and 5 could be associated with the presence of dual/mixed-tropic (DM) variants. The phenotypic assay performed on a subset of sequences confirmed the tropism prediction for concordant sequences and showed that NC values between 4 and 5 are associated with DM tropism. These results suggest that the combination of G2P and NC could increase the accuracy of tropism prediction. A more reliable identification of X4 variants would be useful for better selecting candidates for Maraviroc (MVC) administration, but also as a predictive marker in coreceptor switching, strongly associated with the phase of infection.
Resumo:
These past few years, neoadjuvant strategy has taken an increasing place in the management of breast cancer patients. This strategy is mainly indicated to obtain a tumour bulk regression allowing a breast conserving surgery in patients that otherwise would have undergone mastectomy. Of note, development of new chemotherapy agents and targeted therapies has critically helped in the progress of neoadjuvant strategy as it is currently associated with better pathological response rates. In this context, the pathologist is at the crossroad of this multidisciplinary process. First, he provides on the initial core needle biopsy the tumour pathological characteristics that are critical for the choice of treatment strategy, i.e. histological type, histological grade, proliferative activity (mitotic count and Ki67/MIB1 index labeling), hormone receptor status (oestrogen receptor and progesterone receptor) and HER2 status. Secondly, the pathologist evaluates the pathological response and the status of surgical margins with regards to the residual tumour on the surgical specimen after neoadjuvant treatment. These parameters are important for the management of the patient, since it has been shown that complete pathological response is associated with improved disease free survival. Several grading systems are used to assess the pathological response in breast and axillary lymph nodes. The most frequently used in France are currently the systems described by Sataloff et al. and Chevallier et al. In this review, we detail the different steps involving the pathologist in neoadjuvant setting, with special regards to the quality process and future perspectives such as emerging predictive biomarkers.
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Les dernières recommandations américaines de l'American College of Cardiology et de l'American Heart Association proposent d'abaisser le seuil de prescription de statines pour la prévention cardiovasculaire primaire, et d'abandonner les cibles de LDL-cholestérol pour utiliser le plus souvent des statines de haute intensité. Le Groupe de travail Suisse Lipides et Athérosclérose (GSLA) pense que ces recommandations ne devraient pas être appliquées en Suisse, car elles augmenteraient très fortement le nombre de personnes à bas risque sous statines, chez qui le rapport bénéfice/risque au long cours est incertain, et pourraient diminuer l'importance du style de vie, première priorité dans la prévention cardiovasculaire primaire. En outre, l'abandon des cibles de LDL-cholestérol limite l'individualisation de la prise en charge quant au choix du type et du dosage de la statine, et pourrait diminuer l'adhérence thérapeutique. Pour ces raisons, le GSLA recommande de poursuivre avec les stratégies de prévention bien établies en Suisse et résumées dans les recommandations du GSLA 2012.
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Wound care made great progress during last years related to several factors. The first is an awakening of the importance of wounds. The progress made in the comprehension of the physiopathology of wounds led to innovations in all stages of this complex process which is the wound healing. Autologus platelet concentrate producing growth factors are in use to stimulate the first phase of the healing. The second phase which is the phase of proliferation and secretion is currently better managed with new categories of bandages which are true local treatments. The nutrition became one of the pillars of wound treatments especially among old patients. The reconstructive surgery took great steps since the physiology and the vascular anatomy of the skin and soft tissues are better known. Finally the bio-engineering has entered the treatment of the wound there is more than 20 years ago and methods have improved and become more reliable
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While genetic mutation is a hallmark of cancer, many cancers also acquire epigenetic alterations during tumorigenesis including aberrant DNA hypermethylation of tumor suppressors, as well as changes in chromatin modifications as caused by genetic mutations of the chromatin-modifying machinery. However, the extent of epigenetic alterations in cancer cells has not been fully characterized. Here, we describe complete methylome maps at single nucleotide resolution of a low-passage breast cancer cell line and primary human mammary epithelial cells. We find widespread DNA hypomethylation in the cancer cell, primarily at partially methylated domains (PMDs) in normal breast cells. Unexpectedly, genes within these regions are largely silenced in cancer cells. The loss of DNA methylation in these regions is accompanied by formation of repressive chromatin, with a significant fraction displaying allelic DNA methylation where one allele is DNA methylated while the other allele is occupied by histone modifications H3K9me3 or H3K27me3. Our results show a mutually exclusive relationship between DNA methylation and H3K9me3 or H3K27me3. These results suggest that global DNA hypomethylation in breast cancer is tightly linked to the formation of repressive chromatin domains and gene silencing, thus identifying a potential epigenetic pathway for gene regulation in cancer cells.
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Part 6 of the Manual on Uniform Traffic Control Devices (MUTCD) describes several types of channelizing devices that can be used to warn road users and guide them through work zones; these devices include cones, tubular markers, vertical panels, drums, barricades, and temporary raised islands. On higher speed/volume roadways, drums and/or vertical panels have been popular choices in many states, due to their formidable appearance and the enhanced visibility they provide when compared to standard cones. However, due to their larger size, drums also require more effort and storage space to transport, deploy and retrieve. Recent editions of the MUTCD have introduced new devices for channelizing; specifically of interest for this study is a taller (>36 inches) but thinner cone. While this new device does not offer a comparable target value to that of drums, the new devices are significantly larger than standard cones and they offer improved stability as well. In addition, these devices are more easily deployed and stored than drums and they cost less. Further, for applications previously using both drums and tall cones, the use of tall cones only provides the ability for delivery and setup by a single vehicle. An investigation of the effectiveness of the new channelizing devices provides a reference for states to use in selecting appropriate traffic control for high speed, high volume applications, especially for short term or limited duration exposures. This study includes a synthesis of common practices by state DOTs, as well as daytime and nighttime field observations of driver reactions using video detection equipment. The results of this study are promising for the day and night performance of the new tall cones, comparing favorably to the performance of drums when used for channelizing in tapers. The evaluation showed no statistical difference in merge distance and location, shy distance, or operating speed in either daytime or nighttime conditions. The study should provide a valuable resource for state DOTs to utilize in selecting the most effective channelizing device for use on high speed/high volume roadways where timely merging by drivers is critical to safety and mobility.
Resumo:
Introduction : Les lésions malpighiennes intraépithéliales de bas grade (LSIL) sont un diagnostic rencontré fréquemment lors des frottis de dépistage du cancer du col utérin. Leur prise en charge reste controversée. Au CHUV, avant 2009, un test HPV était effectué chez toutes les femmes avec un diagnostic de L-SIL et seules les patientes avec un test HPV positif pour les hauts risques (HR) étaient adressées en colposcopie. Actuellement, suivant les guidelines européennes de 2006, l'attitude est de faire une colposcopie à toutes les patientes avec un diagnostic initial de L-SIL, sans faire préalablement un test HPV. Cette démarche semble efficiente chez les jeunes patientes, mais pas chez les plus de 30 ans chez qui la prévalence de tests HPV HR positifs est inférieure. Plus de 40% des femmes de plus de 30 ans seraient référées inutilement en colposcopie car elles ne seraient pas infectées par un HPV HR et n'auraient pas de risque d'évolution de leur L-SIL vers une lésion de haut grade. Buts : Comparer les deux différentes prises en charge des femmes de plus de 30 ans présentant un diagnostic de L-SIL, soit celle qui était en vigueur au CHUV avant 2009 et la prise en charge actuelle. Etudier le rôle et l'utilité du test HPV et de la colposcopie dans le suivi de ces femmes. Méthode : Il s'agit d'une étude rétrospective, monocentrique. Nous avons étudié le dossier de toutes les femmes de plus de 30 ans ayant eu une cytologie avec un diagnostic initial de L-SIL du col de l'utérus au CHUV entre le 01.01.09 et le 31.12.10, soit 61 patientes. Résultats : Parmi les 61 femmes inclues dans notre étude 60 ont eu un test HPV effectué lors du diagnostic de L-SIL, dont seuls 29 (48,33%) étaient positifs pour les hauts risques. Comparé aux femmes avec test HPV négatif pour HR, les femmes positives pour HPV HR ont eu un taux inférieur d'évolution spontanément résolutive de leur lésion et un taux supérieur de conisation ou vaporisation du col. Cinq des femmes inclues dans l'étude ont eu une évolution de leurs lésions vers une pathologie plus avancée, dont 4 vers un CIN2 et 1 vers un CIN3. Ces cinq cas étaient positifs pour HPV HR. Conclusion : Les nouvelles guidelines en vigueur au CHUV concernant la prise en charge des femmes avec diagnostic de L-SIL n'étaient pas encore appliquées en 2010, en effet le test HPV a été effectué chez presque la totalité de ces patientes. Ces nouvelles guidelines ne semblent pas être applicables aux femmes de plus de 30 ans, chez qui la prévalence du HPV HR est inférieure, et qui risquent alors de subir des examens complémentaires invasifs, sans qu'il y ait de réel bénéfice sur le pronostic de leur pathologie.