62 research outputs found

    Modelagem das molécutlas correspontentes aos limites de dissociação do sistema HSO2 ao nível coupled-cluster

    Get PDF
    Anais do III Encontro de Iniciação Científica da Unila - Sessão de Matemática e Física I - 06/11/14 – 13h20 às 15h40 - Unila-PTI - Bloco 09 – Espaço 03 – Sala 03Compostos de enxofre desenvolvem um importante papel nas reações químicas que ocorrem na atmosfera, podendo acarretar problemas como a poluição do ar, a chuva ácida e mudanças climáticas globais. Diversos estudos do sistema HSO 2 têm sido empregados com o intuito de caracterizar a Superfície de Energia Potencial (SEP) para o estado eletrônico básico do sistema. Este trabalho, se soma a esses estudos apresentando cálculos ab initio de alto nível dos estados eletrônicos básicos das moléculas que são obtidas nos limites de dissociação da SEP correspondente ao sistema HSO 2 usando o método de cálculo ab initio denominado em inglês Coupled Cluster. Neste trabalho serão reportados os cálculos otimizados ao nível Coupled Cluster com excitações simples e duplas, incluindo correções para excitações triplas usando teoria de perturbações (CCSD(T)), utilizando as bases de funções consistentes em relação à energia de correlação eletrônica introduzidas pelo Dunning incluindo una função extra de ajuste d (aug-cc- pV(X+d)Z) para o átomo de enxofre e funções aug-cc-pVXZ para os átomos de hidrogênio e oxigênio. As otimizações foram feitas com X=3. Os cálculos pontuais com X=2, 4 e 5, para a extrapolação a base infinita da energia das diferentes moléculas, foram feitos em acordo à metodologia usual que utiliza a geometria otimizada (neste caso com X=3). As energias do ponto-zero da energia vibracional e as frequências de vibração dos modos normais de vibração molecular foram obtidos ao mesmo nível de cálculo. As extrapolações para a base infinita foram calculadas usando modelos de dois e de três parâmetros comumente empregados na literatura. Foram realizadas comparações com os dados teóricos e experimentais da literatura especializada. A concordância com os dados experimentais é boa.Bolsista Probic - Unila; Universidade Federal da Integração Latino-Americana (UNILA

    Mise à jour 2014 des recommandations du GEFPICS pour l’évaluation du statut HER2 dans les cancers du sein en France

    Get PDF
    De nouvelles recommandations internationales pour l’évaluation du statut HER2 dans les cancers du sein, basées sur plus de dix ans d’expérience et sur les résultats d’études cliniques et de concordance entre les différentes techniques de détection, viennent tout juste de voir le jour. Le présent article a pour objet de faire le point sur ces nouvelles recommandations, à la lumière de la publication récente du groupe de travail de l’American Society of Clinical Oncology (ASCO) et du Collège des pathologistes américains (CAP), adaptées à la pratique de la pathologie en France et revues par le groupe GEFPICS. À l’ère de la médecine personnalisée, la détermination du statut HER2 reste un élément phare dans le panel des biomarqueurs théranostiques des cancers du sein. Si l’interprétation du statut HER2 dans les cancers du sein est aisée dans la majorité des cas, un certain nombre de situations anatomocliniques est d’interprétation plus délicate, telles que la possibilité rare mais réelle de l’hétérogénéité intra-tumorale du statut de HER2, les formes à différenciation micropapillaire ou la ré-évaluation du statut des biomarqueurs lors de la rechute métastatique. Ces nouvelles recommandations abordent ces différentes questions, reprécisent les conditions pré-analytiques optimales et les critères d’interprétation (notamment des cas 2+), afin de réduire au maximum le risque de faux négatifs. Plus que jamais, la mobilisation de la spécialité d’anatomo-cytopathologie autour de la qualité des tests théranostiques témoigne de son implication dans la chaîne des soins en cancérologie., Summary International guidelines on HER2 determination in breast cancer have just been updated by the American Society of Clinical Oncology (ASCO) and College of American Pathologists (CAP), on the basis of more than ten-year practice, results of clinical trials and concordance studies. The GEFPICS group, composed of expert pathologists in breast cancer, herein presents these recommendations, adapted to the French routine practice. These guidelines highlight the possible diagnosis difficulties with regards to HER2 status determination, such as intra-tumor heterogeneity, special histological subtypes and biomarker re-evaluation during metastatic relapse. Pre-analytical issues and updated scoring criteria (especially for equivocal cases) are detailed, in order to decrease the occurrence of false negative cases. In the era of personalized medicine, pathologists are more than ever involved in the quality of oncotheranostic biomarker evaluation.

    Recommandations du GEFPICS concernant la phase pré-analytique pour l’évaluation de HER2 et des récepteurs hormonaux dans le cancer du sein : mise à jour 2014

    Get PDF
    Les tumeurs fixées et incluses en paraffine sont quotidiennement utilisées pour l’évaluation des biomarqueurs nécessaires au traitement des patientes atteintes d’un cancer du sein invasif. Les nouvelles recommandations internationales sur la phase pré-analytique ont été récemment revues, confirmant l’importance de la prise en charge optimale des prélèvements pour garantir des tests d’immunohistochimie ou d’hybridation in situ de qualité, quel que soit le biomarqueur envisagé. Incluant les procédés de fixation et de préparation des tissus, toutes les procédures pré-analytiques doivent être validées, standardisées et tracées. Elles nécessitent la collaboration et la formation de toutes les personnes impliquées dans le circuit du prélèvement, du préleveur jusqu’au technicien de pathologie et au pathologiste en passant par l’infirmière, ou le coursier. La prise en charge initiale optimale des pièces et une fixation de qualité sont des étapes majeures à maîtriser dans la phase pré-analytique. Cette mise à jour des recommandations du groupe d’étude des facteurs pronostiques immunohistochimiques dans le cancer du sein (GEFPICS) détaille et commente les différentes étapes pré-analytiques. L’observation de ces règles de bonne pratique, l’utilisation rigoureuse de témoins internes et externes et la participation régulière à des programmes d’assurance qualité sont autant de garanties pour une évaluation correcte et pérenne des biomarqueurs oncothéranostiques., Summary Biomarker assessment of breast cancer tumor samples is part of the routine workflow of pathology laboratories. International guidelines have recently been updated, with special regards to the pre-analytical steps that are critical for the quality of immunohistochemical and in situ hybridization procedures, whatever the biomarker analyzed. Fixation and specimen handling protocols must be standardized, validated and carefully tracked. Cooperation and training of the personnel involved in the specimen workflow (e.g. radiologists, surgeons, nurses, technicians and pathologists) are of paramount importance. The GEFPICS’ update of the recommendations herein details and comments the different steps of the pre-analytical process. Application of these guidelines and participation to quality insurance programs are mandatory to ensure the correct evaluation of oncotheranostic biomarkers

    Evolution of overall survival and receipt of new therapies by subtype among 20 446 metastatic breast cancer patients in the 2008-2017 ESME cohort

    Get PDF
    BACKGROUND: Treatment strategies for metastatic breast cancer (MBC) have made great strides over the past 10 years. Real-world data allow us to evaluate the actual benefit of new treatments. ESME (Epidemio-Strategy-Medico-Economical)-MBC, a nationwide observational cohort (NCT03275311), gathers data of all consecutive MBC patients who initiated their treatment in 18 French Cancer Centres since 2008. PATIENTS AND METHODS: We evaluated overall survival (OS) in the whole cohort (N = 20 446) and among subtypes: hormone receptor positive, human epidermal growth factor 2 negative (HR+/HER2-; N = 13 590), HER2+ (N = 3919), and triple-negative breast cancer (TNBC; N = 2937). We performed multivariable analyses including year of MBC diagnosis as one of the covariates, to assess the potential OS improvement over time, and we described exposure to newly released drugs at any time during MBC history by year of diagnosis (YOD). RESULTS: The median follow-up of the whole cohort was 65.5 months (95% CI 64.6-66.7). Year of metastatic diagnosis appears as a strong independent prognostic factor for OS [Year 2016 HR 0.89 (95% CI 0.82-0.97); P = 0.009, using 2008 as reference]. This effect is driven by the HER2+ subcohort, where it is dramatic [Year 2016 HR 0.52 (95% CI 0.42-0.66); P 70% of patients received pertuzumab from 2016 onwards), use of everolimus or eribulin was recorded in less than one-third of HR+/HER2- and TNBC cohorts, respectively, whatever YOD. CONCLUSION: OS has dramatically improved among HER2+ MBC patients, probably in association with the release of several major HER2-directed therapies, whose penetrance was high. This trend was not observed in the other subtypes, but the impact of CDK4/6 inhibitors cannot yet be assessed

    Quality and reporting of clinical guidelines for breast cancer treatment: A systematic review

    Get PDF
    Background: High-quality, well-reported clinical practice guidelines (CPGs) and consensus statements (CSs) underpinned by systematic reviews are needed. We appraised the quality and reporting of CPGs and CSs for breast cancer (BC) treatment. Methods: Following protocol registration (Prospero no: CRD42020164801), CPGs and CSs on BC treatment were identified, without language restrictions, through a systematic search of bibliographic databases (MEDLINE, EMBASE, Web of Science, Scopus, CDSR) and online sources (12 guideline databases and 51 professional society websites) from January 2017 to June 2020. Data were extracted in duplicate assessing overall quality using AGREE II (% of maximum score) and reporting compliance using RIGHT (% of total 35 items); reviewer agreement was 98% and 96% respectively. Results: There were 59 relevant guidance documents (43 CPGs, 16 CSs), of which 20 used systematic reviews for evidence synthesis. The median overall quality was 54.0% (IQR 35.9e74.3) and the median overall reporting compliance was 60.9% (IQR 44.5e84.4). The correlation between quality and reporting was 0.9. Compared to CSs, CPGs had better quality (55.4% vs 44.2%; p ÂĽ 0.032) and reporting (67.18% vs 44.5%; p ÂĽ 0.005). Compared to subjective methods of evidence analysis, guidance documents that used systematic reviews had better quality (76.3% vs 51.4%; p ÂĽ 0.001) and reporting (87.1% vs 59.4%; p ÂĽ 0.001). Conclusion: The quality and reporting of CPGs and CSs in BC treatment were moderately strong. Systematic reviews should be used to improve the quality and reporting of CPGs and CSs.Beatriz Galindo (senor modality) Program by the Ministry of Science, Innovation, and Universities of the Spanish Governmen

    Nothing Lasts Forever: Environmental Discourses on the Collapse of Past Societies

    Get PDF
    The study of the collapse of past societies raises many questions for the theory and practice of archaeology. Interest in collapse extends as well into the natural sciences and environmental and sustainability policy. Despite a range of approaches to collapse, the predominant paradigm is environmental collapse, which I argue obscures recognition of the dynamic role of social processes that lie at the heart of human communities. These environmental discourses, together with confusion over terminology and the concepts of collapse, have created widespread aporia about collapse and resulted in the creation of mixed messages about complex historical and social processes

    Inflammatory Blood Markers as Prognostic and Predictive Factors in Early Breast Cancer Patients Receiving Neoadjuvant Chemotherapy

    No full text
    Background: Inflammatory blood markers, such as neutrophil to lymphocyte ratio (NLR) and platelet to lymphocyte ratio (PLR), have been reported as putative prognostic factors for survival and predictive factors for pathological complete response and toxicity in cancers, however with conflicting results. Methods: We retrospectively analyzed data of 280 patients with early breast cancer receiving neo-adjuvant chemotherapy between 2005 and 2013 in our center. Neutrophil count, lymphocyte count and platelet count before treatment were collected as well as data on pathological complete response, toxicity, recurrence and survival. Results: In multivariate analysis, high PLR was an independent prognostic factor for relapse-free survival (hazard ratio [HR] = 1.91; 95%CI = 1.15–3.16; p = 0.012) and for shorter overall survival (HR = 1.83; 95%CI = 1.03–3.24; p = 0.039). NLR was an independent predictive factor for febrile neutropenia (HR = 0.28; 95%CI = 0.13–0.58; p = 0.001). In triple negative breast cancer molecular subtype, low white blood cell count (<6.75 G/L) was predictive for a higher pathological complete response rate (odds ratio [OR] = 0.29; 95%CI = 0.14–0.61; p < 0.01). Conclusion: In the present study, PLR was found as an independent prognostic factor for survival, while NLR was an independent predictive factor for febrile neutropenia

    Electron transfer to sulfides and disulfides: Intrinsic barriers and relationship between heterogeneous and homogeneous electron-transfer kinetics

    No full text
    The electron-acceptor properties of series of related sulfides and disulfides were investigated in N,N-dimethylformamide with homogeneous (redox catalysis) and/or heterogeneous (cyclic voltammetry and convolution analysis) electrochemical techniques. The electron-transfer rate constants were determined as a function of the reaction free energy and the corresponding intrinsic barriers were determined. The dependence of relevant thermodynamic and kinetic parameters on substituents was assessed. The kinetic data were also analyzed in relation to corresponding data pertaining to reduction of diaryl disulfides. All investigated reductions take place by stepwise dissociative electron transfer (DET) which causes cleavage of the CalkylS or SS bond. A generalized picture of how the intrinsic electrontransfer barrier depends on molecular features, ring substituents, and the presence of spacers between the frangible bond and aromatic groups was established. The reduction mechanism was found to undergo a progressive (and now predictable) transition between common stepwise DET and DET proceeding through formation of loose radical anions. The intrinsic barriers were compared with available results for ET to several classes of dissociative- and nondissociative-type acceptors, and this led to verification that the heterogeneous and the homogeneous data correlate as predicted by the Hush theory
    • …
    corecore