118 resultados para 303.861
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From our reading over the current year 2010 we have singled out 8 items which seem to us significant for the practice of medicine. Small doses of colchicine are useful in the treatment of gout. No efficacious treatment for muscular cramps can be recommended. A cervical collar can be usefully prescribed for the treatment of cervical radiculopathy. A single dose of azithromycin can be envisaged as a third line treatment of syphilis. High doses of vitamin D should not be prescribed for the prevention of fractures in elderly women because of the risks of falling. The wearing of bifocals can be associated with these risks. A clinical score is available to help with the diagnosis of thoracic pain. The NT-pro BNP is of limited use for the follow-up of patients suffering from heart failure.
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BACKGROUND: Postmenopausal women with hormone receptor-positive early breast cancer have persistent, long-term risk of breast-cancer recurrence and death. Therefore, trials assessing endocrine therapies for this patient population need extended follow-up. We present an update of efficacy outcomes in the Breast International Group (BIG) 1-98 study at 8·1 years median follow-up. METHODS: BIG 1-98 is a randomised, phase 3, double-blind trial of postmenopausal women with hormone receptor-positive early breast cancer that compares 5 years of tamoxifen or letrozole monotherapy, or sequential treatment with 2 years of one of these drugs followed by 3 years of the other. Randomisation was done with permuted blocks, and stratified according to the two-arm or four-arm randomisation option, participating institution, and chemotherapy use. Patients, investigators, data managers, and medical reviewers were masked. The primary efficacy endpoint was disease-free survival (events were invasive breast cancer relapse, second primaries [contralateral breast and non-breast], or death without previous cancer event). Secondary endpoints were overall survival, distant recurrence-free interval (DRFI), and breast cancer-free interval (BCFI). The monotherapy comparison included patients randomly assigned to tamoxifen or letrozole for 5 years. In 2005, after a significant disease-free survival benefit was reported for letrozole as compared with tamoxifen, a protocol amendment facilitated the crossover to letrozole of patients who were still receiving tamoxifen alone; Cox models and Kaplan-Meier estimates with inverse probability of censoring weighting (IPCW) are used to account for selective crossover to letrozole of patients (n=619) in the tamoxifen arm. Comparison of sequential treatments to letrozole monotherapy included patients enrolled and randomly assigned to letrozole for 5 years, letrozole for 2 years followed by tamoxifen for 3 years, or tamoxifen for 2 years followed by letrozole for 3 years. Treatment has ended for all patients and detailed safety results for adverse events that occurred during the 5 years of treatment have been reported elsewhere. Follow-up is continuing for those enrolled in the four-arm option. BIG 1-98 is registered at clinicaltrials.govNCT00004205. FINDINGS: 8010 patients were included in the trial, with a median follow-up of 8·1 years (range 0-12·4). 2459 were randomly assigned to monotherapy with tamoxifen for 5 years and 2463 to monotherapy with letrozole for 5 years. In the four-arm option of the trial, 1546 were randomly assigned to letrozole for 5 years, 1548 to tamoxifen for 5 years, 1540 to letrozole for 2 years followed by tamoxifen for 3 years, and 1548 to tamoxifen for 2 years followed by letrozole for 3 years. At a median follow-up of 8·7 years from randomisation (range 0-12·4), letrozole monotherapy was significantly better than tamoxifen, whether by IPCW or intention-to-treat analysis (IPCW disease-free survival HR 0·82 [95% CI 0·74-0·92], overall survival HR 0·79 [0·69-0·90], DRFI HR 0·79 [0·68-0·92], BCFI HR 0·80 [0·70-0·92]; intention-to-treat disease-free survival HR 0·86 [0·78-0·96], overall survival HR 0·87 [0·77-0·999], DRFI HR 0·86 [0·74-0·998], BCFI HR 0·86 [0·76-0·98]). At a median follow-up of 8·0 years from randomisation (range 0-11·2) for the comparison of the sequential groups with letrozole monotherapy, there were no statistically significant differences in any of the four endpoints for either sequence. 8-year intention-to-treat estimates (each with SE ≤1·1%) for letrozole monotherapy, letrozole followed by tamoxifen, and tamoxifen followed by letrozole were 78·6%, 77·8%, 77·3% for disease-free survival; 87·5%, 87·7%, 85·9% for overall survival; 89·9%, 88·7%, 88·1% for DRFI; and 86·1%, 85·3%, 84·3% for BCFI. INTERPRETATION: For postmenopausal women with endocrine-responsive early breast cancer, a reduction in breast cancer recurrence and mortality is obtained by letrozole monotherapy when compared with tamoxifen montherapy. Sequential treatments involving tamoxifen and letrozole do not improve outcome compared with letrozole monotherapy, but might be useful strategies when considering an individual patient's risk of recurrence and treatment tolerability. FUNDING: Novartis, United States National Cancer Institute, International Breast Cancer Study Group.
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This article presents an experimental study about the classification ability of several classifiers for multi-classclassification of cannabis seedlings. As the cultivation of drug type cannabis is forbidden in Switzerland lawenforcement authorities regularly ask forensic laboratories to determinate the chemotype of a seized cannabisplant and then to conclude if the plantation is legal or not. This classification is mainly performed when theplant is mature as required by the EU official protocol and then the classification of cannabis seedlings is a timeconsuming and costly procedure. A previous study made by the authors has investigated this problematic [1]and showed that it is possible to differentiate between drug type (illegal) and fibre type (legal) cannabis at anearly stage of growth using gas chromatography interfaced with mass spectrometry (GC-MS) based on therelative proportions of eight major leaf compounds. The aims of the present work are on one hand to continueformer work and to optimize the methodology for the discrimination of drug- and fibre type cannabisdeveloped in the previous study and on the other hand to investigate the possibility to predict illegal cannabisvarieties. Seven classifiers for differentiating between cannabis seedlings are evaluated in this paper, namelyLinear Discriminant Analysis (LDA), Partial Least Squares Discriminant Analysis (PLS-DA), Nearest NeighbourClassification (NNC), Learning Vector Quantization (LVQ), Radial Basis Function Support Vector Machines(RBF SVMs), Random Forest (RF) and Artificial Neural Networks (ANN). The performance of each method wasassessed using the same analytical dataset that consists of 861 samples split into drug- and fibre type cannabiswith drug type cannabis being made up of 12 varieties (i.e. 12 classes). The results show that linear classifiersare not able to manage the distribution of classes in which some overlap areas exist for both classificationproblems. Unlike linear classifiers, NNC and RBF SVMs best differentiate cannabis samples both for 2-class and12-class classifications with average classification results up to 99% and 98%, respectively. Furthermore, RBFSVMs correctly classified into drug type cannabis the independent validation set, which consists of cannabisplants coming from police seizures. In forensic case work this study shows that the discrimination betweencannabis samples at an early stage of growth is possible with fairly high classification performance fordiscriminating between cannabis chemotypes or between drug type cannabis varieties.
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OBJECTIVE: This article analyses the influence of treatment duration on survival in patients with invasive carcinoma of the cervix treated by radical radiation therapy. METHOD: Three hundred and sixty patients with FIGO stage IB-IIIB carcinoma of the cervix were treated in Lausanne (Switzerland) with external radiation and brachytherapy as first line therapy. Median therapy duration was 45 days. Patients were classified according to the duration of the therapies, taking 60 days (the 75th percentile) as an arbitrary cut-off. RESULTS: The 5-year survival was 61% (S.E. = 3%) for the therapy duration group of less than 60 days and 53% (S.E. = 7%) for the group of more than 60 days. In terms of univariate hazard ratio (HR), the relative difference between the two groups corresponds to a 50% increase of deaths (HR = 1.53, 95% CI = 1.03-2.28) for the longer therapy duration group (P = 0.044). In a multivariate analysis, the magnitude of estimated relative hazards for the longer therapies are confirmed though significance was reduced (HR = 1.52, 95% CI = 0.94-2.45, P = 0.084). CONCLUSION: These findings suggest that short treatment duration is a factor associated with longer survival in carcinoma of the cervix.
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BACKGROUND: Bullous pemphigoid (BP), pemphigus vulgaris (PV) and pemphigus foliaceus (PF) are autoimmune bullous diseases characterized by the presence of tissue-bound and circulating autoantibodies directed against disease-specific target antigens of the skin. Although rare, these diseases run a chronic course and are associated with significant morbidity and mortality. There are few prospective data on gender- and age-specific incidence of these disorders. OBJECTIVES: Our aims were: (i) to evaluate the incidence of BP and PV/PF in Swiss patients, as the primary endpoint; and (ii) to assess the profile of the patients, particularly for comorbidities and medications, as the secondary endpoint. METHODS: The protocol of the study was distributed to all dermatology clinics, immunopathology laboratories and practising dermatologists in Switzerland. All newly diagnosed cases of BP and pemphigus occurring between 1 January 2001 and 31 December 2002 were collected. In total, 168 patients (73 men and 95 women) with these autoimmune bullous diseases, with a diagnosis based on clinical, histological and immunopathological criteria, were finally included. RESULTS: BP showed a mean incidence of 12.1 new cases per million people per year. Its incidence increased significantly after the age of 70 years, with a maximal value after the age of 90 years. The female/male ratio was 1.3. The age-standardized incidence of BP using the European population as reference was, however, lower, with 6.8 new cases per million people per year, reflecting the ageing of the Swiss population. In contrast, both PV and PF were less frequent. Their combined mean incidence was 0.6 new cases per million people per year. CONCLUSIONS; This is the first comprehensive prospective study analysing the incidence of autoimmune bullous diseases in an entire country. Our patient cohort is large enough to establish BP as the most frequent autoimmune bullous disease. Its incidence rate appears higher compared with other previous studies, most likely because of the demographic characteristics of the Swiss population. Nevertheless, based on its potentially misleading presentations, it is possible that the real incidence rate of BP is still underestimated. Based on its significant incidence in the elderly population, BP should deserve more public health concern.
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Delamination and foundering of the lower continental crust (LCC) into the mantle is part of the crust-forming mechanism. However, knowledge of the composition and mineralogy of the preserved or delaminated LCC over geological timescales remains scarce. We provide a synopsis of recent research within the Kohistan arc (Pakistan) and demonstrate that hydrous and less hydrous liquid lines of descent related to flux assisted and decompression mantle melting, respectively, produce compositionally different lower crustal rocks. The argument refers to two lower crustal sections exposed in Kohistan, the older Southern Plutonic Complex (SPC) and the younger Chilas Complex. The SPC typifies a hydrous, high-pressure fractionation sequence of olivine-pyroxenes-garnet-Fe/Ti-oxide-amphibole-plagioclase. The Chilas Complex illustrates a less hydrous fractionation sequence of olivine-clinopyroxene-orthopyroxene-plagioclase-amphibole. Despite the similarity of the Chilas Complex rocks to proposed lower crust compositions, the less hydrous fractionation results in unrealistically small volumes of silica-rich rocks, precluding the Chilas Complex gabbros to represent the magmatic complement to the upper crust. The composition of the SPC lower crust differs markedly from bulk lower crust estimates, but is complementary to silica-rich rocks exposed along this section and in the Kohistan batholith. These observations inspire a composite model for the formation of continental crust (CC) where the negatively buoyant delaminated and the buoyant preserved lower continental crusts (LCC) differ in genesis, mineralogy, and composition. We propose that the upper, non-sedimentary subsequent removal of the complementary, negatively buoyant garnet-pyroxene-amphibole-plagioclase-rich cumulates. In contrast, the LCC, which is buoyant and preserved over geological timescales, is formed by less hydrous parental mantle melts. We suggest that the bulk continental crust composition is related to mixing of these petrologically not directly related end members. Published by Elsevier B.V.
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Canine distemper virus (CDV), a mobillivirus related to measles virus causes a chronic progressive demyelinating disease, associated with persistence of the virus in the central nervous system (CNS). CNS persistence of morbilliviruses has been associated with cell-to-cell spread, thereby limiting immune detection. The mechanism of cell-to-cell spread remains uncertain. In the present study we studied viral spread comparing a cytolytic (non-persistent) and a persistent CDV strain in cell cultures. Cytolytic CDV spread in a compact concentric manner with extensive cell fusion and destruction of the monolayer. Persistent CDV exhibited a heterogeneous cell-to-cell pattern of spread without cell fusion and 100-fold reduction of infectious viral titers in supernatants as compared to the cytolytic strain. Ultrastructurally, low infectious titers correlated with limited budding of persistent CDV as compared to the cytolytic strain, which shed large numbers of viral particles. The pattern of heterogeneous cell-to-cell viral spread can be explained by low production of infectious viral particles in only few areas of the cell membrane. In this way persistent CDV only spreads to a small proportion of the cells surrounding an infected one. Our studies suggest that both cell-to-cell spread and limited production of infectious virus are related to reduced expression of fusogenic complexes in the cell membrane. Such complexes consist of a synergistic configuration of the attachment (H) and fusion (F) proteins on the cell surface. F und H proteins exhibited a marked degree of colocalization in cytolytic CDV infection but not in persistent CDV as seen by confocal laser microscopy. In addition, analysis of CDV F protein expression using vaccinia constructs of both strains revealed an additional large fraction of uncleaved fusion protein in the persistent strain. This suggests that the paucity of active fusion complexes is due to restricted intracellular processing of the viral fusion protein.
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A method is proposed for the estimation of absolute binding free energy of interaction between proteins and ligands. Conformational sampling of the protein-ligand complex is performed by molecular dynamics (MD) in vacuo and the solvent effect is calculated a posteriori by solving the Poisson or the Poisson-Boltzmann equation for selected frames of the trajectory. The binding free energy is written as a linear combination of the buried surface upon complexation, SASbur, the electrostatic interaction energy between the ligand and the protein, Eelec, and the difference of the solvation free energies of the complex and the isolated ligand and protein, deltaGsolv. The method uses the buried surface upon complexation to account for the non-polar contribution to the binding free energy because it is less sensitive to the details of the structure than the van der Waals interaction energy. The parameters of the method are developed for a training set of 16 HIV-1 protease-inhibitor complexes of known 3D structure. A correlation coefficient of 0.91 was obtained with an unsigned mean error of 0.8 kcal/mol. When applied to a set of 25 HIV-1 protease-inhibitor complexes of unknown 3D structures, the method provides a satisfactory correlation between the calculated binding free energy and the experimental pIC5o without reparametrization.
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L'angio-CT post-mortem est un examen peu invasif qui permet d'investiguer le système vasculaire d'une manière détaillée impossible à obtenir lors d'une autopsie conventionnelle. Le groupe de recherche lausannois sur l'angio-CT a développé un protocole standardisé pour une technique appelée «angio-CT post-mortem en phases multiples», qui permet de réaliser des angio-CT de manière simple et d'améliorer le diagnostic radiologique. De plus, de nouveaux équipements incluant une pompe à perfusion, du matériel prêt à l'emploi et un produit de contraste spécifique ont été développés. L'angio-CT permet la détection d'une source d'hémorragie, d'une malformation du système vasculaire, de lésions d'artériosclérose, d'une occlusion d'un vaisseau et la visualisation de l'anatomie vasculaire.
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As collaborators of Anders Pape Møller, we were shocked and surprised to read that he was accused of data fabrication ("Ecologists roiled by misconduct case," G. Vogel, F. Proffitt, R. Stone, News of the Week, 30 Jan., p. 606). We have never had cause to be concerned about any aspect of our collaborations with Møller. He is an amazing scientist, and his great organizational skills are a model for how to be productive in the face of competing time demands. Most of us are capable of much more than we actually accomplish, but we lack the dedication and self-discipline to follow through like Anders Møller. This is the secret of his phenomenal effectiveness that has been so puzzling to the scientific community. His achievements may have caused negative responses from some of his competitors. We would like to see a full, objective, and independent inquiry into the allegations. Our experience tells us that Anders Møller has an exceptionally complete focus on any task at hand, be it fieldwork, data analysis, or paper writing; this, combined with more than a little natural talent, is sufficient to explain his exceptional productivity. We have worked with him on a variety of projects, including collecting data, sometimes under arduous conditions, and in all our dealings with him, his behavior has been beyond reproach. We would ask colleagues to restrain from further public condemnation until such time as any allegations have been proven beyond doubt.
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Light toxicity is suspected to enhance certain retinal degenerative processes such as age-related macular degeneration. Death of photoreceptors can be induced by their exposure to the visible light, and although cellular processes within photoreceptors have been characterized extensively, the role of the retinal pigment epithelium (RPE) in this model is less well understood. We demonstrate that exposition to intense light causes the immediate breakdown of the outer blood-retinal barrier (BRB). In a molecular level, we observed the slackening of adherens junctions tying up the RPE and massive leakage of albumin into the neural retina. Retinal pigment epithelial cells normally secrete vascular endothelial growth factor (VEGF) at their basolateral side; light damage in contrast leads to VEGF increase on the apical side - that is, in the neuroretina. Blocking VEGF, by means of lentiviral gene transfer to express an anti-VEGF antibody in RPE cells, inhibits outer BRB breakdown and retinal degeneration, as illustrated by functional, behavioral and morphometric analysis. Our data show that exposure to high levels of visible light induces hyperpermeability of the RPE, likely involving VEGF signaling. The resulting retinal edema contributes to irreversible damage to photoreceptors. These data suggest that anti-VEGF compounds are of therapeutic interest when the outer BRB is altered by retinal stresses.