21 resultados para Hilduin, 770?-842?

em Biblioteca Digital da Produção Intelectual da Universidade de São Paulo


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Temporal and spatial fluctuations of environmental parameters are normally assigned as causes of variations in morpho-phenological characters of seaweeds and in their epibionts, but formal tests of such hypotheses are lacking, especially in narrow gradients. The present study evaluated the influence of a very small depth gradient (1 to 3 m) and of subtle seasonality characteristic of tropical areas on morpho-phenological traits and on the occurrence of sessile epiphytic organisms using a controlled orthogonal sampling design in a sublittoral population of the tropical brown alga Sargassum cymosum. Four temporal samples were obtained over a one-year period at three depths using nine replicates. The wet weight, maximum length, number of primary and secondary branches, and proportion of secondary branches with receptacles were recorded. Epibiosis was estimated by visual evaluation of percentage cover on secondary branches. Algal morphology varied as a function of the period of the year (weaker effect) and depth (stronger effect) but in different ways for each variable analysed. In general, fronds tended to be shorter, heavier, and more ramified in shallower areas. In relation to time, the morphological characters tended mostly to present higher values in January (summer) and/or April (autumn). Frequency of receptacles did not depend on algal morphology and depth at all but varied in time, although only in the deepest area. Epibiosis also did not depend on algal morphology but varied in relation to time (stronger effect) and, to a lesser extent, depth (weaker effect). The effect of time upon epibiosis also depended on the biological group analysed. These data support the hypothesis that algal morphology varies in relation to period of the year and depth, even under small temporal and spatial environmenal gradients.

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Aim: This study evaluates the contribution of inhibitory pain pathways that descend to the spinal cord through the dorsolateral funiculus (DLF) on the effect of intrathecal gabapentin against spinal nerve ligation (SNL)-induced behavioral hypersensitivity to mechanical stimulation in rats. Main method: Rats were submitted to a sham or complete ligation of the right LS and L6 spinal nerves and a sham or complete DLF lesion. Next, the changes induced by intrathecal administration of gabapentin on the paw withdrawal threshold of rats to mechanical stimulation were evaluated electronically. Key findings: Intrathecal gabapentin (200 mu g/5 mu l) that was injected 2 or 7 days after surgery fully inhibited the SNL-induced behavioral hypersensitivity to mechanical stimulation in sham DLF-Iesioned rats; gabapentin was effective against the SNL-induced behavioral hypersensitivity to mechanical stimulation also in DLF-Iesioned rats. Significance: The effect of intrathecally administered gabapentin against SNL-induced behavioral hypersensitivity to mechanical stimulation in rats does not depend on the activation of nerve fibers that descend to the spinal cord via the DLF. (C) 2012 Elsevier Inc. All rights reserved.

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Introduction: The aim of the present study was to evaluate the physicochemical properties of a bioceramic root canal sealer, Endosequence BC Sealer. Radiopacity, pH, release of calcium ions (Ca2+), and flow were analyzed, and the results were compared with AH Plus cement. Methods: Radiopacity and flow were evaluated according to ISO 6876/2001 standards. For the radiopacity analysis, metallic rings with 10-mm diameter and 1-mm thickness were filled with cements. The radiopacity value was determined according to radiographic density (mm Al). The flow test was performed with 0.05 mL of cement placed on a glass plate. A 120-g weight was carefully placed over the cement. The largest and smallest diameters of the disks formed were measured by using a digital caliper. The release of Ca2+ and pH were measured at periods of 3, 24, 72, 168, and 240 hours with spectrophotometer and pH meter, respectively. Data were analyzed by analysis of variance and Tukey test (P < .05). Results: The bioceramic endodontic cement showed radiopacity (3.84 mm Al) significantly lower than that of AH Plus (6.90 mm Al). The pH analysis showed that Endosequence BC Sealer showed pH and release of Ca2+ greater than those of AH Plus (P < .05) during the experimental periods. The flow test revealed that BC Sealer and AH Plus presented flow of 26.96 mm and 21.17 mm, respectively (P < .05). Conclusions: Endosequence BC Sealer showed radiopacity and flow according to ISO 6876/2001 recommendations. The other physicochemical properties analyzed demonstrated favorable values for a root canal sealer. (J Endod 2012;38:842-845)

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Cerebral amyloid angiopathy (CAA) is an age-associated disease characterized by amyloid deposition in cerebral and meningeal vessel walls. CAA is detected in the majority of the individuals with dementia and also in a large number of non-demented elderly individuals. In addition, CAA is strongly associated with Alzheimer's disease (AD) pathology. Mechanical consequences including intra-cerebral or subarachnoid hemorrhage remains CAA most feared complication, but only a small fraction of CAA results in severe bleeding. On the hand the non-mechanical consequences in cerebrovascular regulation are prevalent and may be even more deleterious. Studies of animal models have provided strong evidence linking the vasoactive A beta 1-40, the main species found in CAA, to disturbances in endothelial-dependent factors, disrupting cerebrovascular regulation Here, we aimed to review experimental findings regarding the non-mechanical consequences of CAA for cerebrovascular regulation and discuss the implications of these results to clinical practice. (C) 2012 Elsevier Inc. All rights reserved.

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The umbilical cord blood (UCB) is an important source of hematopoietic stem cells with great deal of interest in regenerative medicine. The UCB cells have been extensively studied as an alternative to the bone marrow transplants. The challenge is to define specific methods to purify and characterize these cells in different animal species. This study is aimed at morphological characterization of progenitor cells derived from UCB highlighting relevant differences with peripheral blood of adult in dog and cats. Therefore, blood was collected from 18 dogs and 5 cats' umbilical cords from fetus in various developmental stages. The mononuclear cells were separated using the gradient of density Histopaque-1077. Characterization of CD34+ cells was performed by flow cytometric analysis and transmission electron microscopy. Granulocytes (ancestry of the basophiles, eosinophiles, and neutrophiles) and agranulocytes (represented by immature lymphocytes) were identified. We showed for the first time the ultrastructural features of cat UCB cells. Microsc. Res. Tech. 75:766770, 2012. (C) 2011 Wiley Periodicals, Inc.

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Excesses on positron and electron fluxes-measured by ATIC and the PAMELA and Fermi-LAT telescopes-can be explained by dark matter annihilation in the Galaxy, however, it requires large boosts on the dark matter annihilation rate. There are many possible enhancement mechanisms such as the Sommerfeld effect or the existence of dark matter clumps in our halo. If enhancements on the dark matter annihilation cross section are taking place, the dark matter annihilation in the core of the Earth will be enhanced. Here we use recent results from the IceCube 40-string configuration to probe generic enhancement scenarios. We present results as a function of the dark matter-proton interaction cross section, sigma(chi p) weighted by the branching fraction into neutrinos f(nu(nu) over bar) as a function of a generic boost factor B-F, which parametrizes the expected enhancement of the annihilation rate. We find that dark matter models that require annihilation enhancements of O(100) or more and that annihilate significantly into neutrinos are excluded as an explanation for these excesses. We also determine the boost range that can be probed by the full IceCube telescope.

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For the first time, we introduce a generalized form of the exponentiated generalized gamma distribution [Cordeiro et al. The exponentiated generalized gamma distribution with application to lifetime data, J. Statist. Comput. Simul. 81 (2011), pp. 827-842.] that is the baseline for the log-exponentiated generalized gamma regression model. The new distribution can accommodate increasing, decreasing, bathtub- and unimodal-shaped hazard functions. A second advantage is that it includes classical distributions reported in the lifetime literature as special cases. We obtain explicit expressions for the moments of the baseline distribution of the new regression model. The proposed model can be applied to censored data since it includes as sub-models several widely known regression models. It therefore can be used more effectively in the analysis of survival data. We obtain maximum likelihood estimates for the model parameters by considering censored data. We show that our extended regression model is very useful by means of two applications to real data.

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Background: The high and increasing prevalence of Dilated Cardiomyopathy (DCM) represents a serious public health issue. Novel technologies have been used aiming to improve diagnosis and the therapeutic approach. In this context, speckle tracking echocardiography (STE) uses natural myocardial markers to analyze the systolic deformation of the left ventricle (LV). Objective: Measure the longitudinal transmural global strain (GS) of the LV through STE in patients with severe DCM, comparing the results with normal individuals and with echocardiographic parameters established for the analysis of LV systolic function, in order to validate the method in this population. Methods: Seventy-one patients with severe DCM (53 +/- 12 years, 72% men) and 20 controls (30 +/- 8 years, 45% men) were studied. The following variables were studied: LV volumes and ejection fraction calculated by two and three-dimensional echocardiography, Doppler parameters, Tissue Doppler Imaging systolic and diastolic LV velocities and GS obtained by STE. Results: Compared with controls, LV volumes were higher in the DCM group; however, LVEF and peak E-wave velocity were lower in the latter. The myocardial performance index was higher in the patient group. Tissue Doppler myocardial velocities (S', e', a') were significantly lower and E/e' ratio was higher in the DCM group. GS was decreased in the DCM group (-5.5% +/- 2.3%) when compared with controls (-14.0% +/- 1.8%). Conclusion: In this study, GS was significantly lower in patients with severe DCM, bringing new perspectives for therapeutic approaches in this specific population. (Arq Bras Cardiol 2012;99(3):834-842)

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Lectins are carbohydrate-binding proteins of non-imune origin. This group of proteins is distributed widely in nature and they have been found in viruses, microorganisms, plants and animals. Lectins of plants have been isolated and characterized according to their chemical, physical-chemical, structural and biological properties. Among their biological activities, we can stress its fungicidal action. It has been previously described the effect of the lectins Dviol, DRL, ConBr and LSL obtained from the seeds of leguminous plants on the growth of yeasts isolated from vaginal secretions. In the present work the experiments were carried out in microtiter plates and the results interpreted by both methods: visual observations and a microplate reader at 530nm. The lectin concentrations varied from 0.5 to 256 mu g/mL, and the inoculum was established between 65-70% of trammitance. All yeast samples isolated from vaginal secretion were evaluated taxonomically, where were observed macroscopic and microscopic characteristics to each species. The LSL lectin did not demonstrate any antifungal activity to any isolate studied. The other lectins DRL, ConBr and DvioL, showed antifungal potential against yeast isolated from vaginal secretion. These findings offering offer a promising field of investigation to develop new therapeutic strategies against vaginal yeast infections, collaborating to improve women's health.

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In this study, the CH2Cl2 extract from leaves of Piper chimonantifolium was subjected to several chromatographic separation procedures to afford one chromene (gaudichaudianic acid) as a major compound as well as two flavonoids (dihydrooroxylin and pinocembrin) and three steroids (sitosterol, sitosteryl palmitate and stigmasterol). The structures of all determined compounds were characterised by spectrometric analysis, mainly mass spectrometry and NMR, as well as their optical properties. This article describes the first phytochemical study of the leaves of P. chimonantifolium and an evaluation of the antifungal activity of its major compounds.

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Introduction: Human T-cell lymphotropic virus type 1 (HTLV-1) infection is intractable and endemic in many countries. Although a few individuals have severe symptoms, most patients remain asymptomatic throughout their lives and their infections may be unknown to many health professionals. HTLV-1 can be considered a neglected public health problem and there are not many studies specifically on patients' needs and emotional experiences. Objective: To better understand how women and men living with HTLV-1 experience the disease and what issues exist in their healthcare processes. Methods: A qualitative study using participant observation and life story interview methods was conducted with 13 symptomatic and asymptomatic patients, at the outpatient clinic of the Emilio Ribas Infectious Diseases Institute, in Sao Paulo, Brazil. Results and Discussion: The interviewees stated that HTLV-1 is a largely unknown infection to society and health professionals. Counseling is rare, but when it occurs, focuses on the low probability of developing HTLV-1 related diseases without adequately addressing the risk of infection transmission or reproductive decisions. The diagnosis of HTLV-1 can remain a stigmatized secret as patients deny their situations. As a consequence, the disease remains invisible and there are potentially negative implications for patient self-care and the identification of infected relatives. This perception seems to be shared by some health professionals who do not appear to understand the importance of preventing new infections. Conclusions: Patients and medical staff referred that the main focus was the illness risk, but not the identification of infected relatives to prevent new infections. This biomedical model of care makes prevention difficult, contributes to the lack of care in public health for HTLV-1, and further perpetuates the infection among populations. Thus, HTLV-1 patients experience an "invisibility" of their complex demands and feel that their rights as citizens are ignored.

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The number of citations received by authors in scientific journals has become a major parameter to assess individual researchers and the journals themselves through the impact factor. A fair assessment therefore requires that the criteria for selecting references in a given manuscript should be unbiased with regard to the authors or journals cited. In this paper, we assess approaches for citations considering two recommendations for authors to follow while preparing a manuscript: (i) consider similarity of contents with the topics investigated, lest related work should be reproduced or ignored; (ii) perform a systematic search over the network of citations including seminal or very related papers. We use formalisms of complex networks for two datasets of papers from the arXiv and the Web of Science repositories to show that neither of these two criteria is fulfilled in practice. By representing the texts as complex networks we estimated a similarity index between pieces of texts and found that the list of references did not contain the most similar papers in the dataset. This was quantified by calculating a consistency index, whose maximum value is one if the references in a given paper are the most similar in the dataset. For the areas of "complex networks" and "graphenes", the consistency index was only 0.11-0.23 and 0.10-0.25, respectively. To simulate a systematic search in the citation network, we employed a traditional random walk search (i.e. diffusion) and a random walk whose probabilities of transition are proportional to the number of the ingoing edges of the neighbours. The frequency of visits to the nodes (papers) in the network had a very small correlation with either the actual list of references in the papers or with the number of downloads from the arXiv repository. Therefore, apparently the authors and users of the repository did not follow the criterion related to a systematic search over the network of citations. Based on these results, we propose an approach that we believe is fairer for evaluating and complementing citations of a given author, effectively leading to a virtual scientometry.

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This paper aims to provide an improved NSGA-II (Non-Dominated Sorting Genetic Algorithm-version II) which incorporates a parameter-free self-tuning approach by reinforcement learning technique, called Non-Dominated Sorting Genetic Algorithm Based on Reinforcement Learning (NSGA-RL). The proposed method is particularly compared with the classical NSGA-II when applied to a satellite coverage problem. Furthermore, not only the optimization results are compared with results obtained by other multiobjective optimization methods, but also guarantee the advantage of no time-spending and complex parameter tuning.

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Objectives. To evaluate whether the overall dysphonia grade, roughness, breathiness, asthenia, and strain (GRBAS) scale, and the Consensus Auditory Perceptual Evaluation-Voice (CAPE-V) scale show the same reliability and consensus when applied to the same vocal sample at different times. Study Design. Observational cross-sectional study. Methods. Sixty subjects had their voices recorded according to the tasks proposed in the CAPE-V scale. Vowels /a/ and /i/ were sustained between 3 and 5 seconds. Reproduction of six sentences and spontaneous speech from the request "Tell me about your voice" were analyzed. For the analysis of the GRBAS scale, the sustained vowel and reading tasks of the sentences was used. Auditory-perceptual voice analyses were conducted by three expert speech therapists with more than 5 years of experience and familiar with both the scales. Results. A strong correlation was observed in the intrajudge consensus analysis, both for the GRBAS scale as well as for CAPE-V, with intraclass coefficient values ranging from 0.923 to 0.985. A high degree of correlation between the general GRBAS and CAPE-V grades (coefficient = 0.842) was observed, with similarities in the grades of dysphonia distribution in both scales. The evaluators indicated a mild difficulty in applying the GRBAS scale and low to mild difficulty in applying the CAPE-V scale. The three evaluators agreed when indicating the GRBAS scale as the fastest and the CAPE-V scale as the most sensitive, especially for detecting small changes in voice. Conclusions. The two scales are reliable and are indicated for use in analyzing voice quality.

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Contrastes radiológicos iodados – CI são causa de lesão renal aguda – LRA. Avaliar o efeito renoprotetor do bicarbonato de sódio (Bic) sobre a função renal (clearance de creatinina, Jaff é, Clcr-ml/min/100g) e o perfi l oxidativo (excreção de peróxidos, PU e de malondealdeído urinários, FOX-2 e TBARs, nmol/mgCr ) em ratos com CI. Ratos machos adultos Wistar, 250-300g, tratados 1x/dia, por 5 dias, foram divididos nos grupos: Salina (solução salina 0,9%, 3ml/kg/dia, intraperitoneal-i.p.); CI (ioxitalamato de meglumina e sódio, 3ml/kg, i.p); Bic+Salina (Bic 3ml/kg, i.p, 1 hora antes e 1 hora depois da Salina); Bic+CI (Bic 3ml/ kg, i.p, 1 hora antes e 1 hora depois do CI). CI induziu LRA e o Bic confi rmou seu efeito renoprotetor antioxidante (Clcr/TBARs/PU Salina: 0,59±0,03/0,11±0,02/1,29±0,24 vs Bic+Salina 0,58±0,03/0,13±0,02/1,32±0,64 vs CI 0,22±0,02A/0,19±0,02A/4,77±0, 24A vs Bic+CI 0,51±0,04B/0,13±0,3B/1,80± 0,04B, A/B p<0,05). O Bic confi rmou efeito protetor na LRA por CI, podendo ser considerado como possibilidade terapêutica para pacientes submetidos a CI.