46 resultados para Métodos de avaliação do risco de LMEMSLT


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Many prey organisms change their phenotype to reduce the predation risk. However, such changes are associated with trade-offs, and can have negative effects on prey growth or reproduction. Understand how preys assess the predation risk is essential to evaluate the adaptive value of predator-induced phenotypic and its ecological consequences. In this study, we performed a mesocosm experiment to test: i) if growth and stoichiometry of Lithobates catesbeianus tadpoles is altered in response to giant water bug presence (Belostoma spp.); ii) if these responses depend on tadpoles density in environment. Here, we show that tadpoles growth and stoichiometry are not changed by predator presence, neither in low nor in high densities. Our results suggest that tadpoles exposed to predation risk regulate their physiology to preserve the elemental stoichiometric homeostase of their body and excretion. Further, point out to need for future studies that elucidate under what conditions growth and stoichiometry are changed in response to predation risk

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The use of pesticides is being used intensively with severe consequences for exposed farmers. This study aimed to describe the socioeconomic and health profiles of 60 farmers in the city of Touros / RN through the questionnaire recommended by: (International Commission for Protection against Environmental Mutagens and Carcinogens (ICPEMC). The analysis of these data allowed to prove the importance of knowledge about the socioeconomic and health profile of rural farmers as a way to understand the reality of this population, that is vulnerable to exposure due to the lack of knowledge and conditions. Aiming to analyze the frequency of micronucleus (MN) and other nuclear abnormalities in oral mucosa cells of 54 farmers that work in the city of Touros / RN it was applied the micronucleus test (MN) in oral mucosa. Our results showed an increased frequency of MN and other nuclear abnormalities related to the exposure and effects of pesticides on health. Based on the results, it is clear that farmers are using pesticide in the wrong way and compromising their health. A Cordel has been developed as a method to taking the results to the people affected by the pesticides. Therefore this study alerts to the need for profound changes in the social, cultural and health context to reduce health risks for both people and for the environment

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The contamination of water bodies with toxic substances causes a decrease in water quality, representing a risk to public health. In this context, human activities are generally seen as the main sources of water degradation. However, elements found naturally in the environment can also compromise water quality. Thus, the Boqueirão‘s dam, located in the municipality of Parelhas (RN, Brazil), was chosen as area for the development of this study, as its geological region is rich in the emission of natural ionizing radiation that produces byproducts like lead and Radon. Moreover, the area has a strong human influence that enhances the risks of pollutant discharge in this body of water.Thus, the objectives of this study were centered (i) in the analysis of risk perception in the city of Parelhas (RN/Brasil) due to the use of the water from the Boqueirão Dam; and (ii) in the assessment of water quality in the Dam using methods that quantify, mainly, heavy metals and radiation levels, as well as these toxics potential of inducing mutations on genetic material. The analysis of risk perception showed that the population in the city of Parelhas can perceive a risk in using the water from the dam and that they can recognize factors that influence the water quality. Regarding the second objective, the set of data point to the contamination of the Dam by heavy metals, as well as levels of radioactive parcicles and Radon – also present in high concentrations in outdoor air and on soil. Thus, it is possible to infer that the population residing in this area is subjected to injuries caused by exposure to natural and anthropogenic contamination. Our findings corroborate with the perception of the population regarding the risks associated with the use of the Dam for several types of activities. It is expected that the information gathered in this study can substantiate activities and future researches in this semiarid region in the Rio Grande do Norte/Brazil. Also, that the set of data can enable a better understanding of the specific toxicological scenario of risk found for the population and the effect of the contamination for the biota, which aids the development of a future risk assessment and a consequent management of this local issue.

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Background: Zinc is an essential nutrient that is required for numerous metabolic functions, and zinc deficiency results in growth retardation, cellmediated immune dysfunction, and cognitive impairment. Objective: This study evaluated nutritional assessment methods for zinc supplementation in prepubertal nonzinc- deficient children. Design: We performed a randomised, controlled, triple-blind study. The children were divided into a control group (10% sorbitol, n = 31) and an experimental group (10 mg Zn/day, n = 31) for 3 months. Anthropometric and dietary assessments as well as bioelectrical measurements were performed in all children. Results: Our study showed (1) an increased body mass index for age and an increased phase angle in the experimental group; (2) a positive correlation between nutritional assessment parameters in both groups; (3) increased soft tissue, and mainly fat-free mass, in the body composition of the experimental group, as determined using bioelectrical impedance vector analysis; (4) increased consumption of all nutrients, including zinc, in the experimental group; and (5) an increased serum zinc concentration in both groups (p < 0.0001). Conclusions: Given that a reference for body composition analysis does not exist for intervention studies, longitudinal studies are needed to investigate vector migration during zinc supplementation. These results reinforce the importance of employing multiple techniques to assess the nutritional status of populations.

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Background: Zinc is an essential nutrient that is required for numerous metabolic functions, and zinc deficiency results in growth retardation, cellmediated immune dysfunction, and cognitive impairment. Objective: This study evaluated nutritional assessment methods for zinc supplementation in prepubertal nonzinc- deficient children. Design: We performed a randomised, controlled, triple-blind study. The children were divided into a control group (10% sorbitol, n = 31) and an experimental group (10 mg Zn/day, n = 31) for 3 months. Anthropometric and dietary assessments as well as bioelectrical measurements were performed in all children. Results: Our study showed (1) an increased body mass index for age and an increased phase angle in the experimental group; (2) a positive correlation between nutritional assessment parameters in both groups; (3) increased soft tissue, and mainly fat-free mass, in the body composition of the experimental group, as determined using bioelectrical impedance vector analysis; (4) increased consumption of all nutrients, including zinc, in the experimental group; and (5) an increased serum zinc concentration in both groups (p < 0.0001). Conclusions: Given that a reference for body composition analysis does not exist for intervention studies, longitudinal studies are needed to investigate vector migration during zinc supplementation. These results reinforce the importance of employing multiple techniques to assess the nutritional status of populations.

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Brazil is among the largest cashew nut producers of the world. However, the roasting process is still carried out artisanally, especially in the Brazilian semiarid region. In face of this occupational problem, the aim of this study was to perform a physical-chemical characterization of the particulate matter (PM) emitted by the roasting of cashew nuts, as well as to determine the occupational risk and molecular mechanisms associated. The most evident PM characteristics were the prevalence of fine particles, typical biomass burning morphologies such as tar ball and the presence of the elements K, Cl, S, Ca and Fe. In addition, atmospheric modeling analyses suggest that these particles can reach neighboring regions of the emission source. Polycyclic aromatic hydrocarbons (PAHs) with carcinogenic potential, such as benzo[a]pyrene, dibenz[a,h]anthracene, benzo[a]anthracene, benzo[b]fluoranthene, chrysene, benzo[k]fluoranthene, indeno[1,2,3-c,d]pyrene and benzo[j]fluoranthene were the most abundant PAHs found in the two air monitoring campaigns. Among the identified oxy-PAH the benzanthrone (7H-benz[d,e]anthracen-7-one) had the highest concentration and the evaluation of lifetime cancer risk showed an increase of 12 to 37 cases of cancer for every 10,000 exposed people. Chemical analysis of roasted cashew nuts identified the PAHs: phenanthrene, benzo[g,h,i]perylene, pyrene and benzo[a]pyrene, besides the 3-pentadecilfenol allergen (urushiol analogue) as prevalent. Occupational exposure to PAHs was confirmed by the increase of urinary 1-hydroxypyrene levels and genotoxic effects were evidenced by the increase on micronuclei and nuclear bud frequency in exfoliated buccal mucosa cells among the exposed workers. Other biomarkers of effects such as karyorrhexis, pyknotic, karyolytic, condensed chromatin and binucleated cells also have their frequencies increased when compared to an unexposed control group. The investigation of the molecular mechanisms associated with the PM organic extract showed cytotoxicity in human lung cell lines (A549) at concentrations ≥ 4 nM BaPeq. Using non-cytotoxic doses the extract was able to activate proteins involved in the DNA damage response pathway (Chk1 and p53). Moreover, the specific contribution of the four most representative PAHs in the cashew nut roasting sample showed that benzo[a]pyrene was the most efficient to activate Chk1 and p53. Finally, the organic extract was able to increase persistently the mRNA expression involved in the PAHs metabolism (CYP1A1 and CYP1B1), inflammatory response (IL-8 and TNF-α) and cell cycle arrest (CDKN1A) for DNA repair (DDB2). The high PM concentrations and its biological effects associated warn of the serious harmful effects of artisanal cashew nut roasting and urgent actions should be taken to the sustainable development of this activity.

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Brazil is among the largest cashew nut producers of the world. However, the roasting process is still carried out artisanally, especially in the Brazilian semiarid region. In face of this occupational problem, the aim of this study was to perform a physical-chemical characterization of the particulate matter (PM) emitted by the roasting of cashew nuts, as well as to determine the occupational risk and molecular mechanisms associated. The most evident PM characteristics were the prevalence of fine particles, typical biomass burning morphologies such as tar ball and the presence of the elements K, Cl, S, Ca and Fe. In addition, atmospheric modeling analyses suggest that these particles can reach neighboring regions of the emission source. Polycyclic aromatic hydrocarbons (PAHs) with carcinogenic potential, such as benzo[a]pyrene, dibenz[a,h]anthracene, benzo[a]anthracene, benzo[b]fluoranthene, chrysene, benzo[k]fluoranthene, indeno[1,2,3-c,d]pyrene and benzo[j]fluoranthene were the most abundant PAHs found in the two air monitoring campaigns. Among the identified oxy-PAH the benzanthrone (7H-benz[d,e]anthracen-7-one) had the highest concentration and the evaluation of lifetime cancer risk showed an increase of 12 to 37 cases of cancer for every 10,000 exposed people. Chemical analysis of roasted cashew nuts identified the PAHs: phenanthrene, benzo[g,h,i]perylene, pyrene and benzo[a]pyrene, besides the 3-pentadecilfenol allergen (urushiol analogue) as prevalent. Occupational exposure to PAHs was confirmed by the increase of urinary 1-hydroxypyrene levels and genotoxic effects were evidenced by the increase on micronuclei and nuclear bud frequency in exfoliated buccal mucosa cells among the exposed workers. Other biomarkers of effects such as karyorrhexis, pyknotic, karyolytic, condensed chromatin and binucleated cells also have their frequencies increased when compared to an unexposed control group. The investigation of the molecular mechanisms associated with the PM organic extract showed cytotoxicity in human lung cell lines (A549) at concentrations ≥ 4 nM BaPeq. Using non-cytotoxic doses the extract was able to activate proteins involved in the DNA damage response pathway (Chk1 and p53). Moreover, the specific contribution of the four most representative PAHs in the cashew nut roasting sample showed that benzo[a]pyrene was the most efficient to activate Chk1 and p53. Finally, the organic extract was able to increase persistently the mRNA expression involved in the PAHs metabolism (CYP1A1 and CYP1B1), inflammatory response (IL-8 and TNF-α) and cell cycle arrest (CDKN1A) for DNA repair (DDB2). The high PM concentrations and its biological effects associated warn of the serious harmful effects of artisanal cashew nut roasting and urgent actions should be taken to the sustainable development of this activity.

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The presence of cyanobacterial blooms in reservoirs intended for supply to the population can create public health problems for many species could produce potentially toxic compounds and these are not eliminated in the conventional procedures used in water treatment plants. So even in amounts less than the maximum allowable limit imposed by MS, cyanotoxins can be present in drinking water distributed to the population, creating a chronic exposure. There is little information about the long-term effects of oral exposure to cyanotoxins. This work aimed to show the exposure orally (v.o) of animals to a crude extract of cyanobacteria containing cyanotoxins to evaluate the reproductive performance of pregnant rats and their offspring and fertility of male rats. The presence of microcystins (MCs) in samples collected during the flowering processes in freshwater reservoirs in the Rio Grande do Norte, was analyzed by enzyme immunoassay and its variants have been identified and quantified by chromatographic methods. It was observed that by administration v.o. cyanobacterial extract containing MCs (40, 100 or 250 ng of MCs / kg / day) did not cause systemic toxicity in adult rats or effect on reproductive performance of male and female rats treated. It was also not observed any changes in skeletal study in the offspring of pregnant rats treated with the extract above. Because the solutions used contained MCs in a concentration equal to or greater than the tolerable daily intake for MCs, the results suggest, therefore, that the development of this work contributed to better assess public health risk as the oral exposure to cyanotoxins, increasing thus the credibility of the maximum allowable limit (LMP) of MCs in drinking water distributed to the population of several countries that use the LMP established by WHO in its legislation

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Analisar a atuação dos enfermeiros de unidade de terapia intensiva na prevenção da úlcera por pressão. Método: trata-se de estudo descritivo desenvolvido com 13 enfermeiros da unidade de terapia intensiva do Hospital Universitário Onofre Lopes (HUOL), em Natal-RN. Foi aplicado um questionário, submetido à análise de conteúdo temática. O estudo foi aprovado pelo Comitê de Ética da Universidade Federal do Rio Grande do Norte (UFRN), sob o CAAE n. 0240.0.051.000-10. Resultados: os enfermeiros reportaram a realização da mudança de decúbito, a avaliação de risco, a discussão com os colegas sobre as medidas adotadas, a higiene e hidratação da pele do paciente através de uso de ácidos graxos essenciais e hidratante corporal, o cuidado com a disposição dos lençóis, de forma a evitar dobras, a utilização de colchão de ar e a aplicação de placas de hidrocoloide nas proeminências ósseas. Conclusão: a prática da prevenção das úlceras por pressão aplicada pelos enfermeiros da unidade de terapia intensiva ocorre sem padronização dos cuidados

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On the aggravation of social problems and the shortage of resources, the improvement of evaluation methods and control of its application, requiring more efficiency, efficacy, effectiveness and participation in its management, has been growing. As a result, emerges the importance of studying and developing such methodologies. The overall goal of this dissertation is to know what are the difficults to incorporate the point of view of executers and beneficiaries in evaluation process. To do so, has been done a research characterized as qualitative, with a field strategy using the case study of two social projects called Petrobras Child Program, situated in the metropolitan region of Natal, and Content Analysis technique for analyze the data. The conclusions of this work can assist in improving the process of projects evaluation financed by Petrobras, contributing with its social role, besides the possibility of encouraging a greater participation of other society actors, such as beneficiaries, in the evaluation process

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Nowadays, evaluation methods to measure thermal performance of buildings have been developed in order to improve thermal comfort in buildings and reduce the use of energy with active cooling and heating systems. However, in developed countries, the criteria used in rating systems to asses the thermal and energy performance of buildings have demonstrated some limitations when applied to naturally ventilated building in tropical climates. The present research has as its main objective to propose a method to evaluate the thermal performance of low-rise residential buildings in warm humid climates, through computational simulation. The method was developed in order to conceive a suitable rating system for the athermal performance assessment of such buildings using as criteria the indoor air temperature and a thermal comfort adaptive model. The research made use of the software VisualDOE 4.1 in two simulations runs of a base case modeled for two basic types of occupancies: living room and bedroom. In the first simulation run, sensitive analyses were made to identify the variables with the higher impact over the cases´ thermal performance. Besides that, the results also allowed the formulation of design recommendations to warm humid climates toward an improvement on the thermal performance of residential building in similar situations. The results of the second simulation run was used to identify the named Thermal Performance Spectrum (TPS) of both occupancies types, which reflect the variations on the thermal performance considering the local climate, building typology, chosen construction material and studied occupancies. This analysis generates an index named IDTR Thermal Performance Resultant Index, which was configured as a thermal performance rating system. It correlates the thermal performance with the number of hours that the indoor air temperature was on each of the six thermal comfort bands pre-defined that received weights to measure the discomfort intensity. The use of this rating system showed to be appropriated when used in one of the simulated cases, presenting advantages in relation to other evaluation methods and becoming a tool for the understanding of building thermal behavior

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A síndrome dos ovários policísticos (SOP) é a desordem endócrina mais comum em mulheres com idade reprodutiva. Seu diagnóstico é firmado através do consenso de Rotterdam na presença de dois dos seguintes critérios: anovulação crônica, sinais clínicos e/ou bioquímicos de hiperandrogenismo e presença de micropolicistos nos ovários. Na SOP, além das características específicas da síndrome é comum a presença de marcadores de risco cardiovascular aumentado como dislipidemia, hipertensão arterial, resistência à insulina e obesidade central Objetivos: Analisar a acurácia diagnóstica da circunferência da cintura (CC), relação cintura-estatura (RCEst), razão cintura-quadril (RCQ) e índice de conicidade (Índice C) para detecção de fatores de risco cardiovascular (FRCV) e síndrome metabólica (SM) em mulheres com síndrome dos ovários policísticos (SOP). Metodologia: Foi realizado estudo transversal envolvendo 108 mulheres na faixa etária de 20-34 anos, com diagnóstico de SOP de acordo com o consenso de Rotterdam. Foram considerados parâmetros clínicos, antropométricos e bioquímicos de avaliação do risco cardiovascular. A análise dos dados foi desenvolvida em duas etapas, conforme descrito a seguir. Fase 1: análise da acurácia dos pontos de corte previamente determinados na literatura nacional para CC, RCEst, RCQ e Índice C, para predição de FRCV; Fase 2: determinação de pontos de corte dos índices antropométricos supracitados, específicos para mulheres com SOP, para discriminação de SM, através da análise da curva ROC (Receiver Operating Characteristic). Resultados: Com base nos achados da fase 1 do estudo, a RCEst foi o marcador que apresentou correlações positivas significativas com o xi maior número de FRCV (pressão arterial, triglicerídeos e glicemia após teste oral de tolerância à glicose), além de correlação negativa com HDL-colesterol. Os demais marcadores antropométricos se correlacionaram positivamente com pressão arterial, enquanto CC e RCQ apresentaram correlação positiva também com triglicerídeos. Todos os indicadores antropométricos apresentaram taxas de sensibilidade superiores a 60%, com destaque para a RCEst que apresentou sensibilidade superior a 70%. Na fase 2 da pesquisa observamos que a CC, RCEst e RCQ apresentaram desempenho semelhante na predição de SM, sendo superiores ao Índice C. Os valores de ponto de corte dos índices antropométricos para discriminar SM foram: CC = 95 cm; RCEst = 0,59; RCQ = 0,88; e Índice C = 1,25. Utilizando esses pontos de corte as taxas de sensibilidade e especificidade da CC e RCEst foram superiores às observadas para RCQ e Índice C. Conclusões: Nossos dados enfatizam a importância da avaliação antropométrica no rastreamento do risco cardiovascular em mulheres com SOP, destacando-se a relevância da RCEst na predição de FRCV clássicos e a necessidade de considerar pontos de corte específicos para mulheres com SOP para discriminação de SM

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Conselho Nacional de Desenvolvimento Científico e Tecnológico

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Conselho Nacional de Desenvolvimento Científico e Tecnológico

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Bipolar disorder has been growing in several countries. It is a disease with high mortality and has been responsible by the social isolation of the patients. Bipolar patients have alterations in circadian timing system, showing a phase shift in various physiological variables. There are several arguments demonstrating alterations in circadian rhythms may be part of the bipolar disorder pathophysiology. Given the necessity for further elucidation, the goal of this study was to validate the forced desynchronization protocol as an animal model for bipolar disorder. To do this, Wistar rats were submitted to a forced desynchronization protocol which consists in a symmetrical light dark cycle with 22h. Under this protocol, rats dissociate the locomotor activity rhythm into two components: one synchronized to the light / dark cycle with 22h, and another component with period longer than 24 hours following the animal endogenous period. These rhythms with different periods sometimes there is coincidence, which we named CAP (Coincidence Active Phase) and the opposite phase, non-coincidence, called NCAP (Non-Concidence Active Phase). The hypothesis is that in CAP animals present a mania-like behavior and animals in NCAP depressive-like behavior. We found some evidence described in detail throughout this thesis. In sum, the animals under forced desynchronization protocol were more stressed, showed an increase in stereotypic behaviors such as grooming and reduction in other behaviors such as risk assessment and vertical exploration when compared to the control group. The CAP animals showed increased locomotor activity, especially during the dark phase when compared to controls (rats under T24) and less depressive behavior in the forced swim test. The animals in NCAP showed a higher anxiety in elevated plus maze, but they don t have ahnedonia. The animals under dissociation have more labeled 5HT1A cells at the amygdala area, which appoint that they have more amygdala inhibition. Taking these data together, we could partially validated the forced desynchronization protocol as an animal model for mood oscillations