116 research outputs found

    Caracterização funcional da hipertrofia miocárdica induzida pelo isoproterenol e de sua regressão

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    OBJETIVO: Analisar as disfunções da hipertrofia miocárdica induzida pelo isoproterenol e de sua regressão. Corações isolados hipertrofiados por isoproterenol (ISO) (8 dias) e após 22 dias de sua suspensão (regressão) foram distendidos. MÉTODOS: Até pressão de repouso (Pr) de 60mmHg, analisaram-se: pressão desenvolvida máxima (PDmáx.); estresse sistólico (sigmamáx); inclinação da reta estresses/deformações; constante de relaxamento; rigidez da câmara e rigidez miocárdica. RESULTADOS: Nos corações hipertrofiados (H) as variações de volume (deltaV) necessárias para Pr=60mmHg foram heterogêneas. Em alguns (H1; n=10) deltaV equivaleu à dos controle (C) enquanto em outros (H2; n=10) foi inferior, e também diferiram quanto ao peso seco, complacência ventricular, rigidez miocárdica, constante de relaxamento,e sigmamáx. PDmáx dos grupos H1 e H2 foram superiores às de C (n=8) e Regressão (R) (n=8). Contudo, sigmamáx de H2 foi menor que C, H1 e R. O mecanismo de Frank-Starling foi deprimido nos corações hipertrofiados. A constante de relaxamento de H2 indicou retardo no decaimento da pressão associado a menor complacência ventricular e rigidez miocárdica acentuada. CONCLUSÃO: Hipertrofia miocárdica induzida pelo ISO não é homogênea. Alguns corações têm alterações pouco expressivas; outros têm comprometimento das funções sistólica e diastólica. A hipertrofia miocárdica reduz a capacidade de gerar força e aprimora a capacidade em variar pressão por aumento da relação massa/volume. Há, também, comprometimento da complacência ventricular e da rigidez muscular.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Universidade Federal de São Paulo (UNIFESP) Laboratório de Fisiologia CardíacaUNIFESP, Laboratório de Fisiologia CardíacaSciEL

    Impatto organizzativo di radio-223 nel trattamento del mCRPC

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    Le caratteristiche di radio-223 e i vincoli imposti dalle normative vigenti rendono necessari la definizione di un percorso clinico-assistenziale ottimale e di modelli operativi che garantiscano di poter gestire al meglio tutte le potenziali criticità legate all’utilizzo del farmaco nel trattamento del mCRP

    Pennes' bioheat equation vs. porous media approach in computer modeling of radiofrequency tumor ablation

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    [EN] The objective of this study was to compare three different heat transfer models for radiofrequency ablation of in vivo liver tissue using a cooled electrode and three different voltage levels. The comparison was between the simplest but less realistic Pennes' equation and two porous media-based models, i.e. the Local Thermal Non-Equilibrium (LTNE) equations and Local Thermal Equilibrium (LTE) equation, both modified to take into account two-phase water vaporization (tissue and blood). Different blood volume fractions in liver were considered and the blood velocity was modeled to simulate a vascular network. Governing equations with the appropriate boundary conditions were solved with Comsol Multiphysics finite-element code. The results in terms of coagulation transverse diameters and temperature distributions at the end of the application showed significant differences, especially between Pennes and the modified LTNE and LTE models. The new modified porous media-based models covered the ranges found in the few in vivo experimental studies in the literature and they were closer to the published results with similar in vivo protocol. The outcomes highlight the importance of considering the three models in the future in order to improve thermal ablation protocols and devices and adapt the model to different organs and patient profiles.This work was supported by the Spanish Ministerio de Economia, Industria y Competitividad under "Plan Estatal de Investigacion, Desarrollo e Innovacion Orientada a los Retos de la Sociedad", Grant No "RTI2018-094357-B-C21" and by the Italian Government MIUR Grant No "PRIN-2017F7KZWS".Tucci, C.; Trujillo Guillen, M.; Berjano, E.; Iasiello, M.; Andreozzi, A.; Vanoli, GP. (2021). Pennes' bioheat equation vs. porous media approach in computer modeling of radiofrequency tumor ablation. Scientific Reports. 11(1):1-13. https://doi.org/10.1038/s41598-021-84546-6S113111Chu, K. F. & Dupuy, D. E. 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    FOLFOX activity in a rare case of metastatic colonic adenocarcinoma of the tongue: A case report

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    Abstract Background Adenocarcinomas of the oral cavity are rare neoplasms, and only four cases of primary colonic adenocarcinoma of the tongue have ever been described in literature. Very few information about chemotherapy sensitiveness of this type of neoplasia is available, with only one regimen that showed some activity in a metastatic patient. Case presentation We describe the case of a patient bearing a metastatic colonic adenocarcinoma of the tongue submitted to a first-line chemotherapy with oxaliplatin, 5-fluorouracil and folinic acid (FOLFOX regimen). After chemotherapy the patient obtained the complete disappearance of the primitive neoplasia located in the body of the tongue, and a tumor size reduction > 50% of liver and lung metastases. Conclusions This case demonstrated the activity of the combination of oxaliplatin and 5-fluorouracil in this very rare neoplasia. The FOLFOX regimen might be considered either in advanced and especially in the neoadjuvant setting, when the reduction of the primary tumor is highly needed
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