109 resultados para Estresse abiótico


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The main problem faced by the shrimp industry are the infectious diseases. The hypodermal and hematopoietic necrosis infection (IHHN) is one of the major cause of disease in the cultured shrimp, Litopenaeus vannamei. Environmental changes involving water quality, oxygen concentration, salinity, temperature, stocking density, presence of pathogens, among others, triggering a stressing condition for the cultured shrimp, weakening them and allowing the outbreak of diseases. The stress on the animal leads to a change in the molecules immune response components, which can be used as indicators of shrimp health. Thus, the objective of the present study was to evaluate the effect of salinity, stocking density and IHHNV infection on the L. vannamei shrimp. The immune parameters used to check the shrimp health were the total hemocytes counts (THC), the agglutinating activity (AA) and the clotting time (CT) of the serum of shrimp. These parameters were analyzed in healthy and IHHNV-infected shrimp, grown in low (0-0.5 ), medium (19-24 ) and high (> 38 ) salinity, and extensive (7-12 cam.m-2), semi-intensive (15-25 cam.m-2) and intensive (33-45 cam.m -2) stocking density. The IHHNV infection rate was significantly higher in low salinity (P<0.005) and intensive density (P<0.005), both stressful conditions for L. vannamei. Low salinity significantly increased THC (P<0.05) and decreased and CT (P<0.05) in healthy and infected shrimp, but AA (P<0.05) significantly decreased in healthy shrimp at medium salinity. Culture intensification did not affect the THC, AA and CT of healthy and infected shrimp (P>0.05). The IHHNV infection did not affect any immune parameters of shrimp cultured at different salinities and stocking densities. It is necessary to emphasize that this study was conducted in shrimp grown in ponds, where several environmental factors are acting simultaneously. Thus, further studies are needed about the influence of other environmental factors on the immune parameters of shrimp cultured in pond

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It is a Cross-sectional and multi-disciplinary study whose population selection was made by department of human resources (composed by a Manager, an Oncologist and a Psychologist) from the hospital where this research was realized. They also collaborated with important information about the work of that professionals in the hospital. We also counted on a Statistic who made study design calculating the sample and analyzing data. This research issued Evaluating health professionals anxiety levels who care for cancer terminally ill and their feelings about that work as well as identifying the factors which have influence on it. 100 health professionals from the Hospital which is a reference on cancer caring in Brazil situated in the city of Natal, state of Rio Grande do Norte, participated of this research. There was a sample loss of 21%. Data were collected through a questionnaire and State-Trait Anxiety Inventory (STAI). Results showed that 15% of the professionals have low State Anxiety levels, 70% Medium State Anxiety levels and 15% high State anxiety levels. The Number of Patients and Working in another Institution have interfered in the anxiety levels. Doctors and Nursing Assistants and Technicians have got the highest high State Anxiety percentage (25%). 73% of them declare to feel some sort of different behavior and/or feelings in caring for terminally ill. The most remarkable professionals feelings were Suffering and Sadness, and Terminally ill Children was the most difficult age group to care for. We conclude that work overload and having more than one job can interfere in professional stress levels and anxiety. Dealing with terminally ill, specially children one, can cause on the professionals psychological suffering. It s recommended the development of supporting and training strategies to reduce and/or to prevent Stress and Anxiety high levels

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Introdução: Os hormônios estrogênicos possuem importante papel na defesa contra as espécies reativas do oxigênio, fato que se evidencia na maior incidência de doenças cardiovasculares e neurodegenerativas após a menopausa. O exercício físico melhora as defesas antioxidantes, contudo em altas cargas e em baixas concentrações de estrógeno possui efeito aditivo ao dano oxidativo. O ácido α-lipóico possui uma ampla gama de ação antioxidante e poderia contribuir para diminuição do dano nestas condições. Objetivo: O objetivo deste estudo é caracterizar a ação do ácido α-lipóico sobre a adaptação antioxidante e funções reprodutivas de ratas submetidas a natação moderada. Material e métodos: Os animais foram submetidos a natação diária (1 hora) e sacrificados após 30, 60 e 90 dias. Os animais foram divididos em controles sedentários e exercitados; suplementados (ácido α-lipóico 100mg/Kg/dia) sedentários e exercitados e animais ovariectomizados e suplementados com ácido lipóico. Avaliou-se diariamente o ciclo estral e os seguintes marcadores de estresse oxidativos foram mensurados em fígado e sangue: atividade enzimática da SOD, GPx e CAT, além do SRAT e GSH. Resultados: O protocolo de exercício aumentou a duração do ciclo estral no grupo controle exercitado, sobretudo na fase diestral. Neste mesmo grupo, houve diminuição da lipoperoxidação com melhora da atividade antioxidante da SOD e GPx. O grupo exercitado e suplementado não apresentou alteração na duração do ciclo estral e manteve os benefícios sobre o sistema antioxidante antes observado nos animais exercitados. A suplementação antioxidante juntamente com a natação em períodos superiores a 30 dias, diminuiu o processo de adaptação antioxidante quando comparado aos animais somente exercitados. Nos animais ovariectomizados, o exercício e a suplementação com ácido lipóico não promoveu adaptação antioxidante ao contrário dos demais grupos. Conclusão: O aumento na duração do ciclo estral e a melhora nos marcadores de estresse oxidativo seriam uma resposta adaptativa frente ao exercício moderado. O ácido lipóico impediu a alteração no ciclo induzida pelo exercício, mas preservou a melhoria no sistema antioxidante. A depleção estrogênica provocada pela ovariectomia eleva o potencial de dano oxidativo gerado pelo exercício. A ação antioxidante do LA na presença de estrógeno diminuiu excessivamente o dano oxidativo, comprometendo a adaptação antioxidante a natação. Nos animais ovariectomizados, contudo, o AL promoveu adaptação antioxidante ao exercício

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A prática regular de exercício físico possibilita redução dos efeitos das disfunções hormonais e envelhecimento biológico natural que promovem desajustes hemodinâmicos, vasculares e músculo-esqueléticos, principalmente na população feminina no período pós-menopausa. Nesta fase da vida, o exercício aquático representa mais do que uma forma de ajuste funcional, é uma forma de manutenção de independência para as atividades da vida diária (AVD s) e melhoria na qualidade de vida. Este estudo teve como objetivo avaliar as modificações adquiridas pela prática regular de um programa de exercício aquático concorrente de intensidade moderada no nível de óxido nítrico (ON), no índice de resistividade arterial (IR), no perfil lipídico, na capacidade funcional e na qualidade de vida de idosas. A amostra foi formada por idosas (60 a 80 anos) selecionadas por randomização, por sorteio simples divididas em grupo controle e grupo de intervenção as quais foram submetidas a um programa de exercícios aquáticos proposto inicialmente em projeto piloto, por 12 semanas (n=34) e o ensaio clínico teve duração de 16 semanas (n=40). Foi coletada amostra sanguínea das idosas e avaliado o perfil lipídico pelo método enzimático com kit Labtest e o ON por medida indireta a partir da concentração de nitrito no sobrenadante das células em cultura em leitor de ELISA. A avaliação das artérias carótidas e vertebrais foi feita utilizando o método de ultra-som Doopler. A capacidade funcional foi avaliada por quatro testes que simulam atividades da vida diária que são: caminhar 10 metros (C10m), levantar da posição sentada (LPS), levantar da cadeira e locomover-se pela casa (LCLC) e o de levantar-se da posição decúbito ventral (LPDV). No estudo piloto foi avaliado o índice geral de autonomia funcional (IG) e a qualidade de vida através do questionário WHOQOL-100. Empregou-se a análise de variância (ANOVA) com medidas repetidas nos fatores grupo (GH e GC) e tempo (pré e pós-teste) para as comparações intra e intergrupos nas variáveis seguida do post hoc de Scheffé. Utilizou-se o teste de correlação de Pearson e adotado o valor de p<0,05 para a significância estatística. Houve aumento do ON circulante, redução nos índices de resistividade arterial, melhoria significativa nos níveis de colesterol e triglicérides e ganho na capacidade funcional das idosas após a intervenção. Existiu correlação inversa entre a resistividade da artéria vertebral direita (VERTD) e níveis de ON e entre a VERTD e os níveis plasmáticos de HDL, assim como entre estes e o teste C10m nas idosas em estudo. Não houve modificações significativas na qualidade de vida das idosas. Em conclusão, o programa de exercício proposto foi capaz de oferecer melhorias funcionais, aumentar o nível de óxido nítrico circulante, diminuindo a resistência arterial promovendo modificações no perfil lipídico de idosas

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Objectives: The purpose of the current study was to diagnose military police officers in Natal, Brazil as to the level and phase of stress in which they find themselves and the prevalent symptomatology (physical or mental). Methodology: Descriptive, crosscut study that investigated a sample of 264 individuals taken from a population of 3,193 military police officers of the Capital Police Command (CPC) in Natal, Brazil. The data were collected using the Lipp Stress Symptoms for Adults Inventory LSSI, and analyzed by tabulations, percentage calculations, t-test for proportions and Pearson s chi-squared test for associations between stress, symptomatology and military rank. Data collection was between June/2004 and January/2005. Results: It was found that 52.6% of the officers had symptoms of stress and 47.4% symptomatology of stress. This was distributed across all ranks, especially mid and upper-level officers as well as corporals and privates, with predominance in the resistance phase (36%) and a prevalence of psychological symptoms (76%). The only variable investigated that was related to stress was gender (P = 0.0337). Conclusions: It was concluded that there is stress among all ranks of military police officers in Natal, Brazil, especially mid and upper-level officers, corporals and privates, with a prevalence of psychological symptoms, low levels of physical symptoms and predominance in the resistance phase. It seems that stress levels do not differ significantly from those found in Brazilian men and women and do not indicate a situation of chronic fatigue

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Neste trabalho procuramos estudar o fenômeno do bruxismo, definido como o ato de apertar e/ou ranger os dentes, hábito prejudicial à região orofacial relacionado a varáveis psicossociais. O bruxismo é frequentemente associado aos aspectos emocionais, entre os mais ressaltados, a ansiedade e o estresse, podendo implicar em alterações das estruturas orofaciais, modificações funcionais e inclusive com repercussões sociais. Deste modo, torna-se relevante evidenciar que a pesquisa foi desenvolvida, visando o contexto multidisciplinar, abrangendo a Fonoaudiologia, Odontologia e Psicologia. Objetivo: verificar associação entre bruxismo, ansiedade e as principais queixas referentes à função mastigatória. Método: participaram oitenta voluntários, divididos entre grupo com bruxismo (N=40) e sem bruxismo (N=40), do sexo masculino e feminino. O diagnóstico do bruxismo foi realizado através do exame clínico. Para avaliar os níveis de ansiedade empregou-se o Inventário de Ansiedade Traço e Estado e para os aspectos psicossociais um questionário com questões estruturadas referentes às atividades diárias, focando a função mastigatória (para o grupo com bruxismo). Resultados:: Os resultados permitem evidenciar diferenças significativas entre os grupos analisados, a média e desvio padrão de ansiedade estado no grupo com bruxismo, 42,7±9,6 e sem bruxismo 38,6±8,2 (p ≤0,04) e de ansiedade traço respectivamente 44,5±11,0 e controle 40,7±9,5 (p ≤0,11). O relato dos participantes com bruxismo evidenciou como principais queixas durante a mastigação, dor na face ao mastigar, cansaço muscular na face, cefaleia ao mastigar e presença de ruídos articulares. Conclusões: Evidenciamos uma associação dos fatores emocionais como a ansiedade e o bruxismo, e como resultante os pacientes apontam que a função mastigatória encontra-se depreciada

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Purpose: assess the frequency of stress and anxiety levels in infertile women, correlate these aspects with risk factors and qualitatively analyze feelings resultant from the inability to conceive, in order to obtain data for specific psychological guidance. Methods: the case-control study included a total of 302 women, 152 being infertile (case group: 30.3 ± 5.4 years), and 150 non-fertile (control group: 25.7 ± 7.9 years). The quantitative approach involved the application of Lipp s Stress Symptoms Inventory (LSSI) and State-Trait Anxiety Inventory (STAI), whereas the qualitative approach consisted of a semi-structured interview. Response variables considered were: stress frequency and anxiety scores (State and Trait). Statistical analysis compared frequencies and medians between groups, by means of qui-squared and Mann-Whitney tests, respectively, and constructed logistical regression models to test associations between response variables and risk factors considered. Qualitative data were analyzed descriptively and categorized in order to perform correspondence analysis. The level of significance was 5%. Results: in the study sample, stress frequency was higher in the case group than in the control(61.8 and 36.0%, respectively), however, significant differences were not observed between groups in relation to stress phases and predominant symptomology type. With respect to anxiety, there were no significant differences between case and control groups as to median state scores [39.5 (35.0 46.0) and 41.0 (35.7 47.0 ); respectively) and anxiety trait scores [44.0 (34.0 51.0) and 42.0 (36.0 49.2); respectively). Risk factors significantly associated with greater risk for high anxiety scores in the case group were: primary infertility, unawareness of the causal factor, diagnostic phase investigation, religion, lack of children from other marriages and the fact that the woman was previously married. The qualitative approach demonstrated that infertility provokes emotional responses, such as sadness, anxiety, anger, fear and guilt. Conclusions: it can be concluded that infertile women are more vulnerable to stress; however, they are capable of adapting to stressful events without serious physical or psychological compromising

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Schistosomiasis is an ancient disease caused by helminth Schistosoma mansoni and is a public health problem in Brazil. The granulomatous lesion, typical of the disease, associates itself with increase in the oxidative damage through the generation of free radicals. The aim of this work was to evaluate the occurrence of changes in parameters oxidant / antioxidant that are part of the human defense system, and observe whether they would cause oxidative stress in subjects with schistosomiasis. Moreover, correlating with some biochemical and hematological parameters. Two groups were selected for study, consisting of individuals of both sexes, aged between 16 and 30 years. A control group, formed by individuals without schistosomiasis (n = 30) and a test group, formed by individuals with schistosomiasis (n = 30). The evaluation of lipid peroxidation in plasma was performed by determination of malondialdehyde and antioxidant defense by the quantification of reduced glutathione and catalase activity. For the parameters that assess oxidative stress, the results showed a decrease in the content of reduced glutathione and no change in the activity of catalase, with an increase in the value of malondialdehyde. Therefore, the data found suggest the occurrence of oxidative stress in subjects with schistosomiasis. Of the parameters that assess hepatic function, only levels of aspartate aminotransferase have been high, while there was a decrease of bilirubine. There was a significant change in the lipid profile (p <0.5), however with regard to the renal function of patients, there was a decrease in creatinine. The assessment hematological, made through hemogram and the quantification of hemoglobin, shows increase of eosinophils individuals in the group test, which can be related to the presence of the parasite. The amendments suggest the involvement of oxidative stress in the pathophysiology of this disease

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Recently, it has been a increasing interest in the antioxidative role of natural products to aid the endogenous protective biological systems against the deleterious effects of oxygen (ROS) and nitrogen (RNS) reactive species. Many antioxidant compounds, naturally occurring from plant sources. Natural antioxidants can protect and prevent the human body from oxidative stress and retard the progress of many diseases in which free radical are involved. Several plants used in the folk medicine to treat certain disorders that are accompanied by inflammation and other pharmacological properties have been proved their attributed properties, such antioxidant activity. Turnera ulmifolia Linn. var. elegans (Turneraceae), frequently employed by population as a medicinal plant, demonstrated antioxidant activity by in vitro and in vivo assays, using its leaf hydroethanolic extract (10%) he in vitro DPPH radical-scanvenging activity showed a strong antioxidant activity (86.57% ± 0.14), similar to Carduus marianus and catequine effects. For the in vivo assays, adult female Wistar rats (n=48) with carbon tetrachloride hepatic injury induced (2,5mL/kg i.p.) were used, Six groups or rats were uses (n=8) [G1 = control (1,25 mL/kg i.p. vehicle); G2 = CCl4 (2,5 mL/kg i.p.); G3 = CCl4 + extract 7 days (500 mg/kg p.o.); G4 = CCl4 + Legalon® 7 days (50 mg/kg p.o.), G5 = CCl4 + extract 21 days (500 mg/kg p.o.) e G6 = CCl4 + Legalon® 21 days (50 mg/kg p.o.)]. The hepatic oxidative injury was evaluated through biochemical parameters [alanine amino transferase (ALT), aspartate amino transferase (AST)] histopathological study, while thiobarbituric acid reactive products (TBAR), glutathione (GSH), catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GPx) levels were used to evaluate proantioxidant parameters. The plant extract tested was found effective as hepatoprotective as evidenced by a decreasing in the ALT and AST activities (p<0.001) and TBAR (plasma, p<0.001 and liver, p<0.001). Levels of GSH (blood, p<0.001 and liver, p<0.001) and antioxidant enzymes [CAT erythrocyte (p<0.05) and hepatic (p<0.01); SOD erythrocyte (p<0.001) and hepatic (p<0.001); GPx erythrocyte (p<0.001) and hepatic (p<0.001)] were also significantly increased. Histopathological changes induced by CCl4 were significantly reduced by the extract treatment. The data obtained were comparable to that of Legalon®, a reference hepatoprotective drug. The results showed that T. ulmifolia leaf extract protects against CCl4 induced oxidative damage. Therefore, this effect must be associated to its antioxidant activity, attributed to the phenolic compounds, present in these extract, which can act as free radical scavengers

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Bone is a dynamic tissue that is in constant process of remodeling in response to mechanical stress and hormonal changes. This study aimed to understand the relationship between the biochemical changes, which women in the menopausal transition are subject to, and how the use of an alternative therapy with lipoic acid (LA) could influence these changes. The study of double-blind, was carried out in perimenopausal women that underwent a three month treatment with 600 mg of AL compared with another group that received placebo during the same period. This study showed that women had a waist circunference and body mass index above the values recommended by WHO (WC ≥ 80 cm; BMI > 25kg/m2). Associated with this, these women had increased concentrations of total cholesterol and triglycerides, and borderline LDL (Total Cholesterol > 200mg/dL; Triglycerides > 150mg/dL; LDL >130mg/dL). These changes were not affected by treatment with AL. There were no shifts in liver profile (ALT, AST and GGT), kidney profile (urea, creatinine, total protein and albumin), mineral profile (Total Calcium, Ionized Calcium, Phosphorus and Magnesium) as well in bone markers (osteocalcin, Total Alkaline Phosphatase and Tartrate Resistant Acid Phosphatase) after treatment with LA. The results of the oxidative profile showed that treatment with LA decreased GPx activity (p < 0,01), while for the TBARS, GSH and SOD activity there were no differences. With regard to SOD, this enzyme will submit to be high in the placebo group after 3 months of study (p<0,05). The expression of RANKL mRNA was reduced (p < 0,05) and of RANK increased (p <0.001), after treatment with LA, while the expression of IL-6 and TNF-ɑ genes were no changed. We conclude that women already in the perimenopause stage have changes in lipid profile and body composition that could induce shifts in oxidative and bone metabolism. However, LA treatment has provided an effective effect in the oxidative and bone profile since the earliest markers such as GPx activity and mRNA expression of RANKL, respectively, were reduced associated with no change in SOD activity. These results suggest a beneficial and protective effect of LA, indicating it potential as an alternative treatment to help the to prevent the complications associated with estrogen deficiency

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

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Post-menopause is a period of women s life cycle that is characterized by estrogen depletion and therefore increasing cardiovascular diseases, neurodegenerative disorders, urogenital atrophy, osteoporosis, hot flushes and sexual discomfort incidences. Estrogen is a hormone with comfirmed antioxidant action and its depletion is related to oxidative stress instalation and damaging various important biomolecules. Regular physical activity has been identified as a factor involved in reducing women s post-menopausal complications in addition to improving antioxidant defense by reducing the oxidative damage and consequently improving life s quality in this part of the population. This study aims to evaluate the influence of hypoestrogenism in antioxidant adaptation due to regular exercise, by determining reduced glutathione (GSH) and Thiobarbituric Acid Reactive Substances (SRAT) concentrations and antioxidant enzymes glutathione peroxidase (GPx), Superoxide Dismutase (SOD) and Catalase (CAT) activities in blood, brain and liver of rats. To achieve this goal we used 50 Wistar rats, weighing 180-250g which were divided into two groups, control - GC (25) and ooforectomized - GO (25). Each group was subdivided into five subgroups: Not-trained - S (5), Not-trained Acute Exercise - SEA (5), regular exercise 30 days - E30 (5), regular exercise 60 days - E60 (5) and regular exercise 90 days - E90 (5). Each of the three subgroups exercised regularly was subjected to acute exercise on the eve and the day of sacrifice to collect biological samples of blood, liver and brain and subsequent determination of SRAT concentration, GSH content and antioxidant enzymes GPx, SOD and CAT activities. The results indicated that the sedentary animals acutely exercised presented oxidative stress and regular physical activity led to antioxidant adaptation. In ooforectomized group the antioxidant adaptation seen in control animals showed to be impaired. Unlike the results from blood and liver, in brain there was a shield against oxidative damage originated by the exercise and that hypoestrogenism led to a loss of this natural antioxidant potential. Therefore, hypoestrogenism interferes negatively in antioxidant adaptation due to regular exercise

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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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This dissertation focuses on the narratives of children hospitalized with chronic diseases. The overall goal is to deduce, from the look of the child health care, hospital class contributions to the process of school inclusion. The research is part of the qualitative ethnographical approach and is based on the principles and research methods (auto)biographical in education and schooling in hospital. Participated in the investigation 05(five) children, aged between 06 (six) and 12 (twelve) years of age, treated at the Center for Children s Onco-Hematology, Varela Santiago Children s Hospital in Natal-RN. The corpus used for the analysis comprises five (05) narrative interviews, 03 (three) drawings made by children as well as records in the researcher s field diary. The sources were collected during the months of August 2010 to February 2011. The analysis revealed that the inclusion of the hospital class, and ensure the right to education, contributes to the construction of strategies for coping with illness and hospitalization, as it promotes autonomy, comfort, playfulness and self-knowledge, the rand the world, easing the stress of hospitalization. The figure of the teacher took the class hospital in the voices of children, a reliever and minimizing the role of double exclusion that cause illness and hospitalization, showing the contributions to (re) construction of identity and subjectivity constitution strengthened. The children interviewed said that the hospital class leave the hospital more cheerful. The playfulness and learning experiences in the hospital are seen by children as actions that go beyond the physical treatment of the disease, since it provides them with acceptance and understanding of hospitalization and illness, to give them affective security and emotional. In conclusion, the narratives of children confirm that the service class hospital ensures continuity of schooling, but they reveal, namely, that this service provides them socialization among peers and with adults, strengthening the emotional, social and cognitive biopsychosocial perspective of attention

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A laserterapia de baixa potência (LBP) tem demonstrado recentemente ser capaz de aumentar a resistência à fadiga, bem como potencializar o desempenho neuromuscular através de seus efeitos metabólicos e fotoquímicos. Estudos anteriores mostraram que o LBP reduziu o estresse oxidativo do exercício, promovendo um retardo da fadiga muscular e minimizando seus efeitos deletérios. O objetivo desse estudo foi avaliar se a aplicação do LBP antes de um protocolo de fadiga teria efeito sobre o desempenho neuromuscular nas variáveis eletromiográficas e dinamométricas do músculo sóleo em sujeitos saudáveis. Esta pesquisa caracterizou-se como um estudo experimental do tipo ensaio clínico controlado, randomizado e cego, no qual participaram 60 voluntários de ambos os sexos, com faixa etária entre 18 e 28 anos e fisicamente ativos, segundo o questionário internacional para a prática de atividade física (IPAQ). Os sujeitos foram alocados randomicamente em três grupos: Controle (G1), Placebo (G2) e Laser (G3) e todos os voluntários foram submetidos a uma avaliação inicial (AV-1), um Protocolo de Fadiga e uma avaliação final (AV-2), compostas por contrações isocinéticas para flexão plantar a uma velocidade de 90°/s. Os resultados encontrados nesse estudo mostraram que não houve diferença estatística entre os três grupos da pesquisa nas variáveis eletromiográficas de RMS e Frequência Mediana, contudo, em relação à dinamometria, o grupo que recebeu a aplicação do Laser obteve um índice de fadiga significativamente menor (p=0,04) quando comparado aos grupos Controle e Placebo. Além disso, a aplicação do laser pré-exercício também resultou em um aumento nas variáveis de desempenho potência e trabalho. Com isso, pode-se concluir que o LBP foi capaz de melhorar o desempenho do sóleo em sujeitos saudáveis, justificado pelo aumento da resistência à fadiga