Developing clinical indication for multisite pacing.

The artificial activation of the heart modifies the mechanics of contraction and relaxation. While only little basic research has been addressed to this question, clinical observations showed that for hypertrophic as well as dilated cardiomyopathies appropriate pacing techniques can be useful. Pacing can influence the activation sequence. The spread out from a single site is slow, and so hypercontractility deminshed. With the use of multiple electrodes, two atrial and/or two ventricular, conduction delays in the atria or ventricles can be eliminated. Synchronisation of the cardiac activation has an anti-arrhythmic and positiv inotropic effect. This may lead to new indications for pacemakers or better to be named cardiac synchronisers.

Admissions of patients with alcohol intoxication in the Emergency Department: a growing phenomenon.

QUESTION UNDER STUDY: To investigate the change over time in the number of ED admissions with positive blood alcohol concentration (BAC) and to evaluate predictors of BAC level. METHODS: We conducted a single site retrospective study at the ED of a tertiary referral hospital (western part of Switzerland) and obtained all the BAC performed from 2002 to 2011. We determined the proportion of ED admissions with positive BAC (number of positive BAC/number of admissions). Regression models assessed trends in the proportion of admissions with positive BAC and the predictors of BAC level among patients with positive BAC. RESULTS: A total of 319,489 admissions were recorded and 20,021 BAC tests were performed, of which 14,359 were positive, divided 34.5% female and 65.5% male. The mean (SD) age was 41.7(16.8), and the mean BAC was 2.12(1.04) permille (g of ethanol/liter of blood). An increase in the number of positive BAC was observed, from 756 in 2002 to 1,819 in 2011. The total number of admissions also increased but less: 1.2 versus 2.4 times more admissions with positive BAC. Being male was independently associated with a higher (+0.19 permille) BAC, as was each passing year (+0.03). A significant quadratic association with age indicated a maximum BAC at age 53. CONCLUSION: We observed an increase in the percentage of admissions with positive BAC that was not limited to younger individuals. Given the potential consequences of alcohol intoxication, and the large burden imposed on ED teams, communities should be encouraged to take measures aimed at reducing alcohol intoxication.

Chest wall syndrome among primary care patients: a cohort study.

BACKGROUND: The epidemiology of chest pain differs strongly between outpatient and emergency settings. In general practice, the most frequent cause is the chest wall pain. However, there is a lack of information about the characteristics of this syndrome. The aims of the study are to describe the clinical aspects of chest wall syndrome (CWS). METHODS: Prospective, observational, cohort study of patients attending 58 private practices over a five-week period from March to May 2001 with undifferentiated chest pain. During a one-year follow-up, questionnaires including detailed history and physical exam, were filled out at initial consultation, 3 and 12 months. The outcomes were: clinical characteristics associated with the CWS diagnosis and clinical evolution of the syndrome. RESULTS: Among 24 620 consultations, we observed 672 cases of chest pain and 300 (44.6%) patients had a diagnosis of chest wall syndrome. It affected all ages with a sex ratio of 1:1. History and sensibility to palpation were the keys for diagnosis. Pain was generally moderate, well localised, continuous or intermittent over a number of hours to days or weeks, and amplified by position or movement. The pain however, may be acute. Eighty-eight patients were affected at several painful sites, and 210 patients at a single site, most frequently in the midline or a left-sided site. Pain was a cause of anxiety and cardiac concern, especially when acute. CWS coexisted with coronary disease in 19 and neoplasm in 6. Outcome at one year was favourable even though CWS recurred in half of patients. CONCLUSION: CWS is common and benign, but leads to anxiety and recurred frequently. Because the majority of chest wall pain is left-sided, the possibility of coexistence with coronary disease needs careful consideration.

Me interesa : web de notícies personal

El projecte tracta d'un portal web que té com a funció principal mostrar informació de diferents pàgines web en una sola plana web a través dels RSS. La web mostra la informació de diferents maneres: - L'usuari visitant podrà consultar aquella informació que desitgi d'entre tota la informació general de la que disposa la web. - L'usuari registrat pot personalitzar aquella informació que és del seu interès i organitzar-la al gust. Es disposa d'una part per l'administració de la web on es gestiona tota la informació general i es poden consultar informes analítics.

Atrial septal pacing for the termination of atrial fibrillation: study in a biophysical model of human atria.

AIMS: While successful termination by pacing of organized atrial tachycardias has been observed in patients, single site rapid pacing has not yet led to conclusive results for the termination of atrial fibrillation (AF). The purpose of this study was to evaluate a novel atrial septal pacing algorithm for the termination of AF in a biophysical model of the human atria. METHODS AND RESULTS: Sustained AF was generated in a model based on human magnetic resonance images and membrane kinetics. Rapid pacing was applied from the septal area following a dual-stage scheme: (i) rapid pacing for 10-30 s at pacing intervals 62-70% of AF cycle length (AFCL), (ii) slow pacing for 1.5 s at 180% AFCL, initiated by a single stimulus at 130% AFCL. Atrial fibrillation termination success rates were computed. A mean success rate for AF termination of 10.2% was obtained for rapid septal pacing only. The addition of the slow pacing phase increased this rate to 20.2%. At an optimal pacing cycle length (64% AFCL) up to 29% of AF termination was observed. CONCLUSION: The proposed septal pacing algorithm could suppress AF reentries in a more robust way than classical single site rapid pacing. Experimental studies are now needed to determine whether similar termination mechanisms and rates can be observed in animals or humans, and in which types of AF this pacing strategy might be most effective.

Pediatric morphea (localized scleroderma): review of 136 patients.

BACKGROUND: Morphea is an autoimmune inflammatory sclerosing disorder that may cause permanent functional disability and disfigurement. OBJECTIVES: We sought to determine the clinical features of morphea in a large pediatric cohort. METHODS: We conducted a retrospective chart review of 136 pediatric patients with morphea from one center, 1989 to 2006. RESULTS: Most children showed linear morphea, with a disproportionately high number of Caucasian and female patients. Two patients with rapidly progressing generalized or extensive linear morphea and arthralgias developed restrictive pulmonary disease. Initial oral corticosteroid treatment and long-term methotrexate administration stabilized and/or led to disease improvement in most patients with aggressive disease. LIMITATIONS: Retrospective analysis, relatively small sample size, and risk of a selected referral population to the single site are limitations. CONCLUSIONS: These data suggest an increased prevalence of morphea in Caucasian girls, and support methotrexate as treatment for problematic forms. Visceral manifestations rarely occur; the presence of progressive problematic cutaneous disease and arthralgias should trigger closer patient monitoring.

Dopamine receptors on dispersed bovine anterior pituitary cells

The dopamine antagonist [3H]-domperidone-[3H]-DOM-bound to a single class of high-affinity (Kd = 1.24 +/- 0.14 nM) and saturable receptors on dispersed bovine anterior pituitary (AP) cells. The binding of [3H]-DOM was stereoselective and reversible with agonists and antagonists. Dopamine competitions for [3H]-DOM binding modeled best for a single site consistent with an interaction with a homogeneous population of receptors. The mean number of specific binding sites labeled by [3H]-DOM was 53,000 per cell in dispersed AP cells consisting of 42% lactotrophs. Dispersed bovine AP cells attached to extracellular matrix within 3 h, and prolactin secretion from these cells was effectively inhibited by dopamine. Several observations suggested that [3H]-DOM-labeled receptors on dispersed bovine AP cells were restricted to the outer plasma membrane and not internalized. These included (1) the rapid and complete dissociation of specific [3H]-DOM binding; (2) the ability of treatment with acid or proteolytic enzymes to entirely remove specifically bound [3H]-DOM, and (3) the lack of effect of metabolic inhibitors on specific [3H]-DOM binding.

Calcium phosphate transfection generates mammalian recombinant cell lines with higher specific productivity than polyfection.

Transfection with polyethylenimine (PEI) was evaluated as a method for the generation of recombinant Chinese hamster ovary (CHO DG44) cell lines by direct comparison with calcium phosphate-DNA coprecipitation (CaPO4) using both green fluorescent protein (GFP) and a monoclonal antibody as reporter proteins. Following transfection with a GFP expression vector, the proportion of GFP-positive cells as determined by flow cytometry was fourfold higher for the PEI transfection as compared to the CaPO4 transfection. However, the mean level of transient GFP expression for the cells with the highest level of fluorescence was twofold greater for the CaPO4 transfection. Fluorescence in situ hybridization on metaphase chromosomes from pools of cells grown under selective pressure demonstrated that plasmid integration always occurred at a single site regardless of the transfection method. Importantly, the copy number of integrated plasmids was measurably higher in cells transfected with CaPO4. The efficiency of recombinant cell line recovery under selective pressure was fivefold higher following PEI transfection, but the average specific productivity of a recombinant antibody was about twofold higher for the CaPO4-derived cell lines. Nevertheless, no difference between the two transfection methods was observed in terms of the stability of protein production. These results demonstrated the feasibility of generating recombinant CHO-derived cell lines by PEI transfection. However, this method appeared inferior to CaPO4 transfection with regard to the specific productivity of the recovered cell lines.

Initial and Extended Use of Femoral Versus Nonfemoral Double-Lumen Vascular Catheters and Catheter-Related Infection During Continuous Renal Replacement Therapy.

BACKGROUND: The risk of catheter-related infection or bacteremia, with initial and extended use of femoral versus nonfemoral sites for double-lumen vascular catheters (DLVCs) during continuous renal replacement therapy (CRRT), is unclear. STUDY DESIGN: Retrospective observational cohort study. SETTING & PARTICIPANTS: Critically ill patients on CRRT in a combined intensive care unit of a tertiary institution. FACTOR: Femoral versus nonfemoral venous DLVC placement. OUTCOMES: Catheter-related colonization (CRCOL) and bloodstream infection (CRBSI). MEASUREMENTS: CRCOL/CRBSI rates expressed per 1,000 catheter-days. RESULTS: We studied 458 patients (median age, 65 years; 60% males) and 647 DLVCs. Of 405 single-site only DLVC users, 82% versus 18% received exclusively 419 femoral versus 82 jugular or subclavian DLVCs, respectively. The corresponding DLVC indwelling duration was 6±4 versus 7±5 days (P=0.03). Corresponding CRCOL and CRBSI rates (per 1,000 catheter-days) were 9.7 versus 8.8 events (P=0.8) and 1.2 versus 3.5 events (P=0.3), respectively. Overall, 96 patients with extended CRRT received femoral-site insertion first with subsequent site change, including 53 femoral guidewire exchanges, 53 new femoral venipunctures, and 47 new jugular/subclavian sites. CRCOL and CRBSI rates were similar for all such approaches (P=0.7 and P=0.9, respectively). On multivariate analysis, CRCOL risk was higher in patients older than 65 years and weighing >90kg (ORs of 2.1 and 2.2, respectively; P<0.05). This association between higher weight and greater CRCOL risk was significant for femoral DLVCs, but not for nonfemoral sites. Other covariates, including initial or specific DLVC site, guidewire exchange versus new venipuncture, and primary versus secondary DLVC placement, did not significantly affect CRCOL rates. LIMITATIONS: Nonrandomized retrospective design and single-center evaluation. CONCLUSIONS: CRCOL and CRBSI rates in patients on CRRT are low and not influenced significantly by initial or serial femoral catheterizations with guidewire exchange or new venipuncture. CRCOL risk is higher in older and heavier patients, the latter especially so with femoral sites.

Cdc42 oscillations in yeasts.

A fundamental problem in cell biology is how cells define one or several discrete sites of polarity. Through mechanisms involving positive and negative feedback, the small Rho-family guanosine triphosphatase Cdc42 breaks symmetry in round budding yeast cells to define a single site of polarized cell growth. However, it is not clear how cells can define multiple sites of polarization concurrently. We discuss a study in which rod-shaped fission yeast cells, which naturally polarize growth at their two cell ends, exhibited oscillations of Cdc42 activity between these sites. We compare these findings with similar oscillatory behavior of Cdc42 detected in budding yeast cells and discuss the possible mechanism and functional outputs of these oscillations.

Perceptions of twelve-step mutual-help groups and their associations with motivation, treatment attendance and alcohol outcomes among chronically homeless individuals with alcohol problems.

BACKGROUND: Twelve-step mutual-help groups (TMGs) are among the most available forms of support for homeless individuals with alcohol problems. Qualitative research, however, has suggested that this population often has negative perceptions of these groups, which has been shown to be associated with low TMG attendance. It is important to understand this population's perceptions of TMGs and their association with alcohol outcomes to provide more appropriate and better tailored programming for this multiply affected population. The aims of this cross-sectional study were to (a) qualitatively examine perception of TMGs in this population and (b) quantitatively evaluate its association with motivation, treatment attendance and alcohol outcomes. METHODS: Participants (N=62) were chronically homeless individuals with alcohol problems who received single-site Housing First within a larger evaluation study. Perceptions of TMGs were captured using an open-ended item. Quantitative outcome variables were created from assessments of motivation, treatment attendance and alcohol outcomes. RESULTS: Findings indicated that perceptions of TMGs were primarily negative followed by positive and neutral perceptions, respectively. There were significant, positive associations between perceptions of TMGs and motivation and treatment attendance, whereas no association was found for alcohol outcomes. CONCLUSIONS: Although some individuals view TMGs positively, alternative forms of help are needed to engage the majority of chronically homeless individuals with alcohol problems.

Analysis of a Plant Complex Resistance Gene Locus Underlying Immune-Related Hybrid Incompatibility and Its Occurrence in Nature

Mechanisms underlying speciation in plants include detrimental (incompatible) genetic interactions between parental alleles that incur a fitness cost in hybrids. We reported on recessive hybrid incompatibility between an Arabidopsis thaliana strain from Poland, Landsberg erecta (Ler), and many Central Asian A. thaliana strains. The incompatible interaction is determined by a polymorphic cluster of Toll/interleukin-1 receptor-nucleotide binding-leucine rich repeat (TNL) RPP1 (Recognition of Peronospora parasitica1)-like genes in Ler and alleles of the receptor-like kinase Strubbelig Receptor Family 3 (SRF3) in Central Asian strains Kas-2 or Kond, causing temperature-dependent autoimmunity and loss of growth and reproductive fitness. Here, we genetically dissected the RPP1-like Ler locus to determine contributions of individual RPP1-like Ler (R1R8) genes to the incompatibility. In a neutral background, expression of most RPP1-like Ler genes, except R3, has no effect on growth or pathogen resistance. Incompatibility involves increased R3 expression and engineered R3 overexpression in a neutral background induces dwarfism and sterility. However, no individual RPP1-like Ler gene is sufficient for incompatibility between Ler and Kas-2 or Kond, suggesting that co-action of at least two RPP1-like members underlies this epistatic interaction. We find that the RPP1-like Ler haplotype is frequent and occurs with other Ler RPP1-like alleles in a local population in Gorzów Wielkopolski (Poland). Only Gorzów individuals carrying the RPP1-like Ler haplotype are incompatible with Kas-2 and Kond, whereas other RPP1-like alleles in the population are compatible. Therefore, the RPP1-like Ler haplotype has been maintained in genetically different individuals at a single site, allowing exploration of forces shaping the evolution of RPP1-like genes at local and regional population scales.

Design and implementation of a multipurpose reactor for scale-up studies

In the theoretical part, the different polymerisation catalysts are introduced and the phenomena related to mixing in the stirred tank reactor are presented. Also the advantages and challenges related to scale-up are discussed. The aim of the applied part was to design and implement an intermediate-sized reactor useful for scale-up studies. The reactor setting was tested making one batch of Ziegler–Natta polypropylene catalyst. The catalyst preparation with a designed equipment setting succeeded and the catalyst was analysed. The analyses of the catalyst were done, because the properties of the catalyst were compared to the normal properties of Ziegler–Natta polypropylene catalyst. The total titanium content of the catalyst was slightly higher than in normal Ziegler–Natta polypropylene catalyst, but the magnesium and aluminium content of the catalyst were in the normal level. By adjusting the siphonation tube and adding one washing step the titanium content of the catalyst could be decreased. The particle size of the catalyst was small, but the activity was in a normal range. The size of the catalyst particles could be increased by decreasing the stirring speed. During the test run, it was noticed that some improvements for the designed equipment setting could be done. For example more valves for the chemical feed line need to be added to ensure inert conditions during the catalyst preparation. Also nitrogen for the reactor needs to separate from other nitrogen line. With this change the pressure in the reactor can be kept as desired during the catalyst preparation. The proposals for improvements are presented in the applied part. After these improvements are done, the equipment setting is ready for start-up. The computational fluid dynamics model for the designed reactor was provided by cooperation with Lappeenranta University of Technology. The experiments showed that for adequate mixing with one impeller, stirring speed of 600 rpm is needed. The computational fluid dynamics model with two impellers showed that there was no difference in the mixing efficiency if the upper impeller were pumping downwards or upwards.

La ferme du Bas-de-la-Baie, 1673-1759 : contribution zooarchéologique à l'étude des sites ruraux

Ce mémoire présente les résultats d'une recherche zooarchéologique portant sur deux occupations d'un site du début de la colonisation à Baie-Saint-Paul (XVIIe-XVIIIe siècle). L'analyse de leurs assemblages fauniques, totalisant 1175 restes osseux, a démontré le caractère diamétralement opposé des deux occupations. Le site d'habitation des goudronniers a révélé une exploitation des ressources sauvages visant à suppléer un élevage déficient et fournir un revenu d'appoint par le commerce des fourrures. Pour sa part, le site de la ferme établie par le Séminaire de Québec a révélé une alimentation basée sur les produits de l'élevage, mais supplée par la chasse de gibier disponible dans les environs immédiats du site. La différence d'exploitation faunique soulignée par l'étude zooarchéologique du site de la ferme du Bas-de-la-Baie a également permis de confirmer le rôle central de l'élevage pour les sites ruraux de la vallée laurentienne tout en soulignant leur variabilité, visible au sein de l'élevage et dans l'apport supplémentaire fourni par la chasse et la pêche.

La pratique médicale des omnipraticiens : influence des contextes organisationnel et géographique

L’utilisation des services de santé est au centre de l’organisation des soins. La compréhension des processus qui déterminent cette utilisation est essentielle pour agir sur le système de santé et faire en sorte qu’il réponde mieux aux besoins de la population. L’objectif de cette thèse est de comprendre le phénomène complexe qu’est l’utilisation des services de santé en s’intéressant à la pratique des médecins omnipraticiens. En nous appuyant sur le cadre théorique de Donabedian, nous décomposons les déterminants de l’utilisation des services de santé en trois niveaux : le niveau individuel, le niveau organisationnel, et le niveau environnemental. Pour tenir compte de la complexité des phénomènes de cette étude nous proposons de nous appuyer sur l’approche configurationnelle. Notre question de recherche est la suivante : dans quelle mesure le mode d’exercice des omnipraticiens influence-t-il la prestation des services et comment l’environnement géographique et la patientèle modulent-ils cette relation ? Nous avons utilisé des bases de données jumelées du Collège des médecins du Québec, de la Régie d’assurance maladie du Québec et de la banque de données iCLSC. Notre échantillon est constitué des médecins omnipraticiens de l’année 2002, ayant satisfait aux critères d’inclusion, ce qui représente près de 70% de la population totale. Des analyses de correspondances multiples et des classifications ascendantes hiérarchiques ont été utilisées pour réaliser la taxonomie des modes d’exercice et des contextes géographiques. Nous avons construit des indicateurs d’utilisation des services de santé pour apprécier la continuité, la globalité, l’accessibilité et la productivité. Ces indicateurs ont été validés en les comparant à ceux d’une enquête populationnelle. Nous présentons tout d’abord les modes d’exercice des médecins qui sont au nombre de sept. Deux modes d’exercice à lieu unique ont émergé : le mode d’exercice en cabinet privé d'une part, caractérisé par des niveaux de continuité et productivité élevés, le mode d’exercice en CLSC d'autre part présentant un niveau de productivité faible et des niveaux de globalité et d'accessibilité légèrement au-dessus de la moyenne. Dans les cinq autres modes d’exercice, les médecins exercent leur pratique dans une configuration de lieux. Deux modes d’exercice multi-institutionnel réunissent des médecins qui partagent leur temps entre les urgences, les centres hospitaliers et le cabinet privé ou le CLSC. Les médecins de ces deux groupes présentent des niveaux d’accessibilité et de productivité très élevés. Le mode d’exercice le moins actif réunit des médecins travaillant en cabinet privé et en CHLSD. Leur niveau d’activité est inférieur à la moyenne. Ils sont caractérisés par un niveau de continuité très élevé. Le mode d’exercice ambulatoire regroupe des médecins qui partagent leur pratique entre le CLSC, le cabinet privé et le CHLSD. Ces médecins présentent des résultats faibles sur tous les indicateurs. Finalement le mode d’exercice hospitaliste réunit des médecins dont la majorité de la pratique s’exerce en milieu hospitalier avec une petite composante en cabinet privé. Dans ce mode d’exercice tous les indicateurs sont faibles. Les analyses ont mis en évidence quatre groupes de territoires de CSSS : les ruraux, les semi-urbains, les urbains et les métropolitains. La prévalence des modes d’exercice varie selon les contextes. En milieu rural, le multi-institutionnel attire près d’un tiers des médecins. En milieu semi-urbain, les médecins se retrouvent de façon plus prédominante dans les modes d’exercice ayant une composante CLSC. En milieu urbain, les modes d’exercice ayant une composante cabinet privé attirent plus de médecins. En milieu métropolitain, les modes d’exercice moins actif et hospitaliste attirent près de 40% des médecins. Les omnipraticiens se répartissent presque également dans les autres modes d’exercice. Les niveaux des indicateurs varient en fonction de l’environnement géographique. Ainsi l’accessibilité augmente avec le niveau de ruralité. De façon inverse, la productivité augmente avec le niveau d’urbanité. La continuité des soins est plus élevée en régions métropolitaines et rurales. La globalité varie peu d’un contexte à l’autre. Pour pallier à la carence de l’analyse partielle de l’organisation de la pratique des médecins dans la littérature, nous avons créé le concept de mode d’exercice comme la configuration de lieux professionnels de pratique propre à chaque médecin. A notre connaissance, il n’existe pas dans la littérature, d’étude qui ait analysé simultanément quatre indicateurs de l’utilisation des services pour évaluer la prestation des services médicaux, comme nous l’avons fait. Les résultats de nos analyses montrent qu’il existe une différence dans la prestation des services selon le mode d’exercice. Certains des résultats trouvés sont documentés dans la littérature et plus particulièrement quand il s’agit de mode d’exercice à lieu unique. La continuité et la globalité des soins semblent évoluer dans le même sens. De même, la productivité et l’accessibilité sont corrélées positivement. Cependant il existe une tension, entre les premiers indicateurs et les seconds. Seuls les modes d’exercice à lieu unique déjouent l’arbitrage entre les indicateurs, énoncé dans l’état des connaissances. Aucun mode d’exercice ne présente de niveaux élevés pour les quatre indicateurs. Il est donc nécessaire de travailler sur des combinaisons de modes d’exercice, sur des territoires, afin d’offrir à la population les services nécessaires pour l’atteinte concomitante des quatre objectifs de prestation des services. Les modes d’exercice émergents (qui attirent les jeunes médecins) et les modes d’exercice en voie de disparition (où la prévalence des médecins les plus âgés est la plus grande) sont préoccupants. A noter que les modes d’exercice amenés à disparaître répondent mieux aux besoins de santé de la population que les modes d’exercice émergents, au regard de tous nos indicateurs. En conclusion, cette thèse présente trois contributions théoriques et trois contributions méthodologiques. Les implications pour les recherches futures et la décision indiquent que, si aucune mesure n’est mise en place pour renverser la tendance, le Québec risque de vivre des pénuries dans la prestation des services en termes de continuité, globalité et accessibilité.