2,080 research outputs found

    Estudio epidemiológico de cáncer en la adolescencia en centro de referencia

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    OBJECTIVE: To analyze the epidemiological characteristics of adolescents with cancer referred to an oncologic center, between 2000 and 2006. METHODS: A retrospective descriptive study was carried out in order to evaluate the epidemiological data of patients aged between ten and 19 years at diagnosis and admitted at the Institute of Oncology (IOP/Graacc) of Universidade Federal de São Paulo (UNIFESP), Brazil, between 2000 and 2006. RESULTS: Among 2,362 patients admitted during this period with a diagnosis of cancer, 629 (26.6%) were adolescents. Mean age was 13.7 years, being 56.8% male. Regarding race, 60.7% of the patients were white, 30% mulattoes, 6.5% blacks, and 2.5% of patients had no characterization of race in the medical records. The most frequent types of tumors were: central nervous system tumors (22.1%), osteosarcoma (14.6%), lymphoma (14.5%), and leukemia (14.5%). The overall survival at five years was 73.7%. Adolescents with the diagnosis of rhabdomyosarcoma presented disseminated disease and histology of worse prognosis, which contributed for increasing the mortality rate of this group of patients. CONCLUSIONS: Adolescents with cancer are a group of patients with distinct characteristics when compared to other cancer groups. Our results show differences in the prevalence of tumors during adolescence and childhood, in the later leukemias and central nervous system tumors predominate. It is crucial to facilitate the access of adolescents to oncologic centers in order to provide early diagnosis and proper treatment.OBJETIVO: Analizar las características epidemiológicas de los adolescentes portadores de neoplasias encaminados al Instituto de Oncología Pediátrica (IOP/GRAACC) de la Universidad Federal de São Paulo, entre los años 2000 a 2006. MÉTODOS: Se trata de un estudio retrospectivo descriptivo, en el que fueron evaluados los datos epidemiológicos de los pacientes, con edad entre 10 y 19 años al diagnóstico, admitidos entre los años de 2000 y 2006 en el IOP/GRAACC. RESULTADOS: Del total de 2.362 pacientes admitidos en ese periodo con diagnóstico de cáncer, 629 (26,6%) eran adolescentes. El promedio de edad fue de 13,8 años, siendo la mayoría del sexo masculino (56,8%). Respecto a la raza, 60,7% de los pacientes eran blancos. Los tipos de tumores más frecuentes fueron: tumores de sistema nervioso central (22,1%), osteosarcoma (14,6%), linfomas (14,5%) y leucemias (14,5%). La sobrevida global en cinco años de los 629 pacientes de este estudio fue de 73,7%. Se subraya que los adolescentes con rabdomiosarcoma admitidos al presente estudio presentaban enfermedad diseminada e histología de peor prognosis, contribuyendo al aumento en la tasa de mortalidad de este grupo de pacientes. CONCLUSIONES: Los adolescentes con cáncer corresponden a un grupo de pacientes que presenta características peculiares si comparados a otros grupos oncológicos. Hay diferencia histológica de los tumores de los adolescentes con los de la infancia, en que predominan leucemias y tumores del sistema nervioso central. En ese contexto, es fundamental facilitar el acceso de esos pacientes a centros especializados y ofrecer medios apropiados al diagnóstico temprano y tratamiento adecuado.OBJETIVO: Analisar as características epidemiológicas dos adolescentes portadores de neoplasias encaminhados para o Instituto de Oncologia Pediátrica (IOP/GRAACC) da Universidade Federal de São Paulo (UNIFESP), entre os anos de 2000 a 2006. MÉTODOS: Trata-se de um estudo retrospectivo descritivo, em que foram avaliados os dados epidemiológicos dos pacientes, com idade entre dez e19 anos ao diagnóstico, admitidos do ano 2000 a 2006 no IOP/Graacc. RESULTADOS: Do total de 2.362 pacientes admitidos neste período com diagnóstico de câncer, 629 (26,6%) eram adolescentes. A idade média encontrada foi de 13,8 anos, sendo a maioria do sexo masculino (56,8%). Em relação à raça, 60,7% dos pacientes eram brancos. Os tipos de tumores mais frequentes foram: tumores de sistema nervoso central (22,1%), osteossarcoma (14,6%), linfomas (14,5%) e leucemias (14,5%). A sobrevida global, em cinco anos, dos 629 pacientes deste estudo foi de 73,7%. Destaca-se que os adolescentes com rabdomiossarcoma apresentavam doença disseminada e histologia de pior prognóstico, contribuindo para o aumento na taxa de mortalidade deste grupo de pacientes. CONCLUSÕES: Os adolescentes com câncer correspondem a um grupo de pacientes que apresenta características peculiares quando comparado a outros grupos oncológicos. Há diferença histológica dos tumores dos adolescentes com os da infância, em que predominam leucemias e tumores do sistema nervoso central. Nesse contexto, é fundamental facilitar o acesso desses pacientes a centros especializados e oferecer meios apropriados para o diagnóstico precoce e tratamento adequado.Universidade Federal de São Paulo (UNIFESP), Escola Paulista de Medicina (EPM)UNIFESP Instituto de Oncologia Pediátrica Grupo de Apoio ao Adolescente e a Criança com CâncerUNIFESP, EPMUNIFESP, Instituto de Oncologia Pediátrica Grupo de Apoio ao Adolescente e a Criança com CâncerSciEL

    Circulating microparticles and central blood pressure according to antihypertensive strategy

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    OBJECTIVES: This prospective, randomized, open-label study aimed to compare the effects of antihypertensive treatment based on amlodipine or hydrochlorothiazide on the circulating microparticles and central blood pressure values of hypertensive patients. METHODS: The effects of treatments on circulating microparticles were assessed during monotherapy and after the consecutive addition of valsartan and rosuvastatin followed by the withdrawal of rosuvastatin. Each treatment period lasted for 30 days. Central blood pressure and pulse wave velocity were measured at the end of each period. Endothelial, monocyte, and platelet circulating microparticles were determined by flow cytometry. Central blood pressure values and pulse wave velocity were recorded at the end of each treatment period. RESULTS: No differences in brachial blood pressure were observed between the treatment groups throughout the study. Although similar central blood pressure values were observed during monotherapy, lower systolic and diastolic central blood pressure values and early and late blood pressure peaks were observed in the amlodipine arm after the addition of valsartan alone or combined with rosuvastatin. Hydrochlorothiazide-based therapy was associated with a lower number of endothelial microparticles throughout the study, whereas a higher number of platelet microparticles was observed after rosuvastatin withdrawal in the amlodipine arm. CONCLUSIONS: Despite similar brachial blood pressure values between groups throughout the study, exposure to amlodipine was associated with lower central blood pressure values after combination with valsartan, indicating a beneficial interaction. Differences between circulating microparticles were modest and were mainly influenced by rosuvastatin withdrawal in the amlodipine arm

    Study of temperature effect on macro-synthetic fiber reinforced concretes by means of Barcelona tests: An approach focused on tunnels assessment

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    This paper presents an experimental investigation on the applicability of the Barcelona (BCN) test to evaluate the mechanical properties of a macro-synthetic fiber reinforced concrete (MSFRC) submitted to high temperature environments (up to 600 °C). BCN tests demonstrated that the MSFRC gradually loses tensile strength an energy consumption density with increasing temperature. Temperatures of 400 °C and 570 °C shown to be critical to the MSFRC mechanical performance. The residual mechanical behavior of the macro-synthetic fibers was not affected by the temperature up to 100 °C. For higher temperatures, the reinforcement showed that may lose part of its crystallinity compromising the MSFRC post-cracking performance. The constitutive model used to determine the stress-strain curves of the MSFRC was capable to reproduce the composite behavior after the event of a fire

    Enhanced ferromagnetism in CuO nanowires on the top of CuO nanograins.

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    In the past few years, a considerable effort has been devoted in order to grow magnetoelectric nanostructured materials. Besides fundamental science, they are very attractive in the electronic/spintronic industry as well as magnetic storage media, solar energy conversion due to their nanometer scale. It is believed that CuO is a magnetoelectric multiferroic system where a ferroelectric order is induced by the onset of a magnetic coupling at low temperatures. Furthermore, its simplest composition is the bases of cuprates which bring about the well-known high-temperature superconductivity. Bulk samples of CuO (which has an unpaired electron in the d-shell) show two antiferromagnetic phase transitions – a commensurate collinear state with the magnetic moments along the monoclinic b axis at TN ~ 213 K and an incommensurate spiral state with half of the magnetic moments in the ac plane at TN ~ 230 K

    Brain-inspired nanophotonic spike computing:challenges and prospects

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    Nanophotonic spiking neural networks (SNNs) based on neuron-like excitable subwavelength (submicrometre) devices are of key importance for realizing brain-inspired, power-efficient artificial intelligence (AI) systems with high degree of parallelism and energy efficiency. Despite significant advances in neuromorphic photonics, compact and efficient nanophotonic elements for spiking signal emission and detection, as required for spike-based computation, remain largely unexplored. In this invited perspective, we outline the main challenges, early achievements, and opportunities toward a key-enabling photonic neuro-architecture using III-V/Si integrated spiking nodes based on nanoscale resonant tunnelling diodes (nanoRTDs) with folded negative differential resistance. We utilize nanoRTDs as nonlinear artificial neurons capable of spiking at high-speeds. We discuss the prospects for monolithic integration of nanoRTDs with nanoscale light-emitting diodes and nanolaser diodes, and nanophotodetectors to realize neuron emitter and receiver spiking nodes, respectively. Such layout would have a small footprint, fast operation, and low power consumption, all key requirements for efficient nano-optoelectronic spiking operation. We discuss how silicon photonics interconnects, integrated photorefractive interconnects, and 3D waveguide polymeric interconnections can be used for interconnecting the emitter-receiver spiking photonic neural nodes. Finally, using numerical simulations of artificial neuron models, we present spike-based spatio-temporal learning methods for applications in relevant AI-based functional tasks, such as image pattern recognition, edge detection, and SNNs for inference and learning. Future developments in neuromorphic spiking photonic nanocircuits, as outlined here, will significantly boost the processing and transmission capabilities of next-generation nanophotonic spike-based neuromorphic architectures for energy-efficient AI applications. This perspective paper is a result of the European Union funded research project ChipAI in the frame of the Horizon 2020 Future and Emerging Technologies Open programme.</p

    Omega-3 supplementation from pregnancy to postpartum to prevent depressive symptoms: a randomized placebo-controlled trial

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    Background: Low n-3 polyunsaturated fatty acids (PUFAs) has been linked to depression, but the preventive effect of n-3PUFAs supplementation on maternal depression needs further investigation. We aimed to evaluate the efficacy of a daily dose of n-3 PUFAs supplementation (fish oil) on the prevention of postpartum depression (PPD). Methods: A randomized, placebo-controlled, double blind trial was designed and nested into a cohort study conducted in Rio de Janeiro, Brazil. Sixty pregnant women identified as being at risk for PPD were invited and randomly assigned to receive fish oil capsules [1.8 g (1.08 g of Eicosapentaenoic (EPA) and 0.72 g of Docosapentaenoic (DHA) acids)] or placebo (control). The Edinburgh Postnatal Depression Scale (EPDS) was scored at 5–13 (T0, baseline), 22–24 (T1), 30–32 weeks of gestation (T2) and 4–6 weeks’ postpartum (T3). Supplementation started at week 22–24 of gestation (T1) and lasted for 16 weeks. Serum fatty acids were assayed to evaluate compliance. Prevalence of EPDS ≥11 was the primary outcome, and mean and changes in EPDS score, length of gestation, and birth weight the secondary outcomes. Linear mixed-effect (LME) and random-intercept logistic regression models were performed to test the effect of fish oil supplementation on prevalence of EPDS ≥11 and EPDS scores variation. Results: In intention-to-treat (ITT) analysis, at 30–32 weeks’ gestation women in the fish oil presented higher serum concentration of EPA, DHA and lower n-6/n-3 ratio comparing to the control group. There were no differences between intervention and control groups in the prevalence of EPDS ≥11, EPDS scores over time, or in changes in EPDS scores from pregnancy to postpartum in either the ITT or per-protocol analyses. Women in the fish oil group with previous history of depression presented a higher reduction on the EPDS score from the second to the third trimester in the fish oil comparing to the control group in the ITT analyses [−1.0 (−3.0–0.0) vs. -0.0 (−1.0–3.0), P = 0.038). These results were confirmed on the LME model (β = −3.441; 95%CI: -6.532– -0.350, P = 0.029). Conclusion: Daily supplementation of 1.8 g of n-3 PUFAs during 16 weeks did not prevent maternal depressive symptoms in a sample of Brazilian women
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