67 resultados para Alostase. Envelhecimento da população. Cortisol


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The advantages of the use of vegetable fibers on the synthetic fibers, such as glass fibers, in the reinforcements in composites are: low cost, low density, good tenacity, good thermal properties and reduced use of instruments for their treatment or processing. However, problems related to poor performance of some mechanical natural fibers, have hindered its direct use in structural elements. In this sense, the emergence of alternative materials such as hybrids composites, involving natural and synthetic fibers, has been encouraged by seeking to improve the performance of structural composites based only on natural fibers. The differences between the physical, chemical and mechanical properties of these fibers, especially facing the adverse environmental conditions such as the presence of moisture and ultraviolet radiation, is also becoming a concern in the final response of these composites. This piece of research presents a comparative study of the strength and stiffness between two composite, both of ortoftalic polyester matrix, one reinforced with fibers of glass-E (CV) and other hybrid reinforced with natural fibers of curauá and fiberglass-E (CH). All the comparative study is based on the influence of exposure to UV rays and steam heated water in composites, simulating the aging environment. The conditions for the tests are accelerated through the use of the aging chamber. The composites will be evaluated through tests of uniaxial static mechanical traction and bending on three points. The composite of glass fiber and hybrid manufacturing industry are using the rolling manual (hand lay-up) and have been developed in the form of composites. All were designed to meet possible structural applications such as tanks and pipes. The reinforcements used in composites were in the forms of short fiber glass-E quilts (450g/m2 - 5cm) of continuous wires and fuses (whose title was of 0.9 dtex) for the curauá fibers. The results clearly show the influence of aging on the environmental mechanical performance of the composite CV and CH. The issues concerning the final characteristics of the fracture for all types of cargoes studied were also analyzed

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There are a number of damaging mechanisms that various materials can suffer in service. However, when working with polymer composite materials, this is something that requires analysis, especially when exposed to adverse environmental conditions. Thus, the objective of the present thesis is the study of the direct influence of environmental aging and the form of hybridization of the reinforcement woven on the structural stability, surfacedegradation and fracture process of polymer composites laminates. For this, the development of two polymer composite laminates was necessary, where one of them was reinforced with a bi-directional woven with hybrid strandsofkevlar-49/glass-Efibers, and the other also with a bi-directionalwoven, however with weft and warpformed of alternating strandsof Kevlar-49 fibers and glass-E fiber The reinforcementwoven are industrially manufactured. Both laminates use a polyester resin as a matrixand are made up of four layers each. All laminates were industrially prepared by the hand lay-up method of manufacturing. To do this, test specimens were manufactured of the respective laminates and submitted to environmental aging accelerated through the aging chamber. They were exposed to alternating cycles of UV radiation and moisture (heated steam) for a standard defined period. At the end of the exposure period the specimens were subjected to mechanical tests of uniaxial tensile and bending in three points and to the characterizationsof the fracture and surface deterioration. In addition, they were submitted to a structural degradation assessment by the measurement of mass variation technique (MMVT) and the measurement of thickness variation technique (MTVT), this last technique being developed in this thesis. At the end of the analysis it was observed that the form of hybridization of the reinforcement woven and the aging process directly influence with losses or gain in mechanical properties, with losses in the structural degradation and in the formation and propagation of damage mechanism of the developedcomposite laminates

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The growing demand in the use of composite materials necessitates a better understanding of its behavior related to many conditions of loading and service, as well as under several ways of connections involved in mechanisms of structural projects. Within these project conditions are highlighted the presence of geometrical discontinuities in the area of cross and longitudinal sections of structural elements and environmental conditions of work like UV radiation, moisture, heat, leading to a decrease in final mechanical response of the material. In this sense, this thesis aims to develop studies detailed (experimental and semi-empirical models) the effects caused by the presence of geometric discontinuity, more specifically, a central hole in the longitudinal section (with reduced cross section) and the influence of accelerated environmental aging on the mechanical properties and fracture mechanism of FGRP composite laminates under the action of uniaxial tensile loads. Studies on morphological behavior and structural degradation of composite laminates are performed by macroscopic and microscopic analysis of affected surfaces, in addition to evaluation by the Measurement technique for mass variation (TMVM). The accelerated environmental aging conditions are simulated by aging chamber. To study the simultaneous influence of aging/geometric discontinuity in the mechanical properties of composite laminates, a semiempirical model is proposed and called IE/FCPM Model. For the stress concentration due to the central hole, an analisys by failures criteria were performed by Average-Stress Criterion (ASC) and Point-Stress Criterion (PSC). Two polymeric composite laminates, manufactured industrially were studied: the first is only reinforced by short mats of fiberglass-E (LM) and the second where the reinforced by glass fiber/E comes in the form of bidirectional fabric (LT). In the conception configurations of laminates the anisotropy is crucial to the final mechanical response of the same. Finally, a comparative study of all parameters was performed for a better understanding of the results. How conclusive study, the characteristics of the final fracture of the laminate under all conditions that they were subjected, were analyzed. These analyzes were made at the macroscopic level (scanner) microscope (optical and scanning electron). At the end of the analyzes, it was observed that the degradation process occurs similarly for each composite researched, however, the LM composite compared to composite LT (configurations LT 0/90º and LT ±45º) proved to be more susceptible to loss of mechanical properties in both regarding with the central hole as well to accelerated environmental aging

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The utilization of synthetic fibers for plastic reinforcement is more and more frequent and this growing interest requires that their mechanic behavior under the most variable conditions of structural applications be known. The use of such materials in the open and exposed to the elements is one of them. In this case, it becomes extremely necessary to study their mechanical properties (strength, stiffness) and the mechanism of fracture by which the environment aging them out. In order to do that, the material must be submitted to hot steam and ultraviolet radiation exposure cycles, according to periods of time determined by the norms. This study proposal deals with the investigation of accelerated environmental aging in two laminated polymeric composites reinforced by hybrid woven made up of synthetic fibers. The configurations of the laminated composites are defined as: one laminate reinforced with hybrid woven of glass fibers/E and Kevlar fibers/49 (LHVK) and the other laminate is reinforced with hybrid tissue of glass fibers/E and of carbon fibers AS4 (LHVC). The woven are plane and bidirectional. Both laminates are impregnated with a thermofix resin called Derakane 470-300 Epoxy Vinyl-Ester and they form a total of four layers. The laminates were industrially manufactured and were made through the process of hand-lay-up. Comparative analyses were carried out between their mechanical properties by submitting specimen to uniaxial loading tractions and three-point flexion. The specimen were tested both from their original state, that is, without being environmentally aging out, and after environmental aging. This last state was reached by using the environmental aging chamber

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This work aims to analyze the policy of economic promotion in the Brazilian cities of medium and great size (with population above of 50.000 hab.). The objective of the research is to launch light in the debate on the regional and municipal development, presenting the recent hypotheses supplied by literature. Of complementary form, had for specific objective presents the results of the Research of Basic Information of Cities - PIM, of Brazilian Institute of Geography and Statistics (IBGE), in two surveys carried through together to the Brazilian local governments (1999 and 2009). It analyzes the instruments of economic promotion used by local governments and the influence of the development variables, as the Local Human Index of Development (HID-L) and the Local Gross Domestic Product (GDP-L). The research sample that factors as HID-L and GDP-L has significant influence in economic promotion of cities and must be taken in account in the definition of the local strategies of development

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The strength of respiratory muscle are frequently assessed by maximal inspiratory and expiratory pressure, however, the maneuvers to assess PImax and PEmax are difficult for many patients. The sniff nasal inspiratory pressure (SNIP) is a simple and noninvasive technique use to assess inspiratory muscles strength. Reference values have been previous established for SNIP in adults but no previous studies have provided reference values for SNIP in adult Brazilian population. The main objective of this study were propose reference values of SNIP for Brazilian population through establishment of relationship between anthropometric measurements, physical activity profile and SNIP and at the same time compare the values obtained with reference values previously published. We studied 117 subjects (59 male and 58 female) distributed in different age grouped 20-80 years old. The results showed on significant positive relationship between SNIP and height and negative correlation with age (p<0.05). In the multiple linear regression analysis only age continued to have an independent predictive role for the two dependent variables that correlated with SNIP. The values of SNIP found in Brazilian population were higher when compared with predict values of previous studies. The results of this study provide reference equations of SNIP for health Brazilian population from 20 to 80 years old

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The frailty in the elderly is characterized by decreased physiological reserves, and is associated with increased risk of disability and high vulnerability to morbidity and mortality. This study is part of a multicentric project on Frailty in Elderly Brazilians (REDE FIBRA). Aims: to investigate characteristics, prevalence and associated factors related to frailty. Metodology: We interviewed 391 elderly patients aged 65 years, selected randomly. Data collection was performed using a multidimensional questionnaire containing information about socio-demographic and clinical variables. To characterize the frail elderly, was considered the phenotype proposed by Fried. Data were analyzed using descriptive statistics, bivariate analysis (χ ²) and binary logistic regression. Results: The prevalence of frailty was 17.1%. In the final model of multivariate analysis, was obtained as factors associated with frailty: advanced chronological age (p <0.001), have comorbidity (p <0.035), show dependence on performing basic activities of daily living (p <0.010) and instrumental (p <0.003) and have poor perception of health status (p <0030). Conclusions: The factors associated with frailty suggest a predictive model helping to understand the syndrome, guiding actions that minimize adverse effects on the aging process

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Introdução: The scales of cognitive screening are important tools for early detection of dementia, creating the possibility of developing measures to slow this process and assist in the management of the disease. Objective: To validate the Leganés Cognitive Test (Prueba Cognitive de Leganés) (PCL) for cognitive screening in low educated elderly Brazilians. Methods: The study sample was composed of 59 elderly residents from the city of Santa Cruz, Brazil with low schooling levels. Reliability was analyzed with a 2-day interval between assessments, and concurrent validity was assessed using the Mini Mental State Examination (MMSE). Results: According to the PCL, the prevalence of dementia was 11.8%. The scale items showed a moderate to strong correlation between domains (p <0.01), and inter-rater reliability exhibited ICC = 0.81, 95% CI (0.72-0.88). Factor analysis resulted in two factors: memory and orientation. Interscale agreement was considered poor (k = - 0.02), supporting the hypothesis of an educational impact on final MMSE scores. Conclusion: The results suggest that PCL has acceptable levels of reliability for use in low educated elderly Brazilians

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Introduction: The SPPB provides information about physical function and is a predictor of adverse events in the elderly. Frailty is a multidimensional syndrome that increases susceptibility to diseases and disability. However it may be possible to prevent or postpone frailty if is identified early. Our objective is to analyze SPPB s ability in screening for frailty a community-dwelling young elderly from cities with distinct socioeconomic conditions. Methods: Data were originated from community dwelling adults (65-74 years old) in Canada (Saint Bruno; n = 60) and Brazil (Santa Cruz; n = 64). SPPB was used to assess physical performance. Frailty was defined as the presence of ≥ 3 of these criteria: weight loss, exhaustion, weakness, mobility limitation and low physical activity. One point was given for each criterion met, totalizing a frailty score ranged from 0 to 5. The Linear Regression and Receiver Operating Characteristics analyses were performed to evaluate the SPPB s screening ability. Results: Mean age was 69.48, 10.0% of the Saint Bruno s sample and 28.1% of Santa Cruz s were frail (p = 0.001), the SPPB score means were 9.6 and 8.5 respectively (p = 0.01). SPPB correlated with the frailty score (R2 = 0.33), with better results for Saint Bruno. A cutoff of 9 in SPPB had good sensitivity and specificity in discriminating frail from non frail in Saint Bruno (AUC = 0.81) but showed fair results in Santa Cruz (AUC = 0.61). Conclusion: The SPPB has moderate ability in predicting frailty among older adult s population, and is an useful test to identify people with good functionality and low frailty when SPPB scores are ≥9

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Background: The Pilates Method is a modality of exercise that has been growing in recent decades, but few researches has been conducted with elderly and little is known about its benefits in this population. Objective: To evaluate the effect of a program of Mat Pilates exercises in muscle performance and postural balance in elderly women. Materials and Method: This is a randomized controlled trial that evaluated the muscle performance (isokinetic dynamometer Biodex System 3 Pro®) and postural balance (Balance Master System®) of 33 women aged 65-80 years. The experimental group (EG) participated of a 12-week program of Mat Pilates exercises with two weekly sessions. Data normality was verified by the Shapiro - Wilk test and were adopted p value < 0.05 as significance level. Results: There were no differences between groups after training. However, the EG showed an increase in the values of extension and flexion average power to 60 ° / s after training (32.19 W to 37.04 W and 14.48 W to 17.56 W, respectively). Conclusion: The proposed exercise program was not effective in the total work and average power of flexor and extensor of the knee, as well as static and dynamic balance of participants

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Introdução: Vem sendo crescente o número de pesquisas que buscam o entendimento das relações entre os desfechos adversos à saúde e as concentrações do cortisol salivar, o qual é um marcador de estresse biológico. O cortisol parece seguir dois estágios de resposta: em situações de baixo/moderado estresse ocorre ativação do eixo Hipotálamo-Pituitária-Adrenal, aumentando o nível do cortisol, entretanto, quando o estresse persiste, o eixo HPA parece tornar-se hipoativo. A sintomatologia depressiva parece ter relação com as concentrações do cortisol, no entanto, essa relação é controversa na literatura. Objetivo: Analisar a relação entre sintomatologia depressiva e concentrações do cortisol em uma amostra de idosos do Nordeste brasileiro, residentes na comunidade. Métodos: Estudo observacional analítico, de caráter transversal, em uma amostra de 256 idosos (≥ 65 anos), residentes na comunidade. A sintomatologia depressiva foi avaliada pela versão brasileira da Center for Epidemiologic Studies-Depression Scale (≥ 16) e as concentrações do cortisol através da coleta salivar (ao acordar, 30 minutos após acordar, 60 minutos após acordar, às 15 horas e antes de dormir), além de medidas compostas. Como co-variáveis foram avaliadas condições sociodemográficas e de saúde. Para análise das medidas do cortisol entre idosos com e sem presença da sintomatologia depressiva, e entre os sexos, foi realizado o teste t de Student. Para verificar as diferenças entre as medidas do cortisol em cada curva foi utilizada a Análise de Variância (ANOVA) de medidas repetidas, com teste post-hoc de Bonferroni. Resultados: Houve diferença significativa para a medida de cortisol salivar ao acordar, entre os idosos com presença e ausência da sintomatologia depressiva (p=0,04). Não houve significância em relação ao sexo. Na análise entre as medidas de cada curva, foi observado que nos idosos com sintomatologia depressiva a 1ª medida não teve diferença significativa em relação à 2ª e 3ª medidas. Além disso, não houve diferença significativa da 4ª medida em relação à 5ª, demonstrando um maior nível noturno de cortisol para os idosos com sintomatologia depressiva, sem declínio, com aspecto plano da curva. Conclusão: Parece existir relação entre sintomatologia depressiva e hipocortisolismo. Entretanto, no Brasil, as condições adversas de vida podem levar ao estresse crônico e serem fatores fortes suficientes para sobrepor maiores diferenças que pudessem existir em relação à presença da sintomatologia depressiva

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Introduction: Hypoestrogenism is the main characteristic of female aging. It promotes significant changes in body composition, both in fat mass as in lean body mass, leading to a decrease in muscle strength and physical performance. Objective: The aim of this study was to test whether menopausal status and hormone levels are associated with muscular strength and physical performance in middle-aged women. Methods: In a cross-sectional study it was collected sociodemographic data, gynecological history, anthropometric and biochemical measures in women aged 40 to 65 years in Parnamirim-RN. The menopause status (pre, peri and post menopause) was determined by menstrual history. All women underwent three dimensions of physical performance assessment: handgrip dynamometry, gait speed and chair stands test - Short Physical Performance Battery (SPPB). Categorical data were presented as absolute and relative frequencies. Quantitative data were showed as mean and standard deviation and the normality of distribution was verified with Kolmogorov-Smirnov (KS) test. Biochemical measures of estradiol and follicle-stimulating hormone (FSH) were transformed to log10. ANOVA with Tukey post-test for comparison of variables between the groups pre, peri and post-menopausal was performed and then multiple linear regression analyzes. Results: Two hundred and seventy eight women aged 50.2 (±5.58) years composed this study, being 50 women in premenopausal status (18%), 122 in perimenopausal (43.9%), and 106 postmenopausal stage (38.1%). The groups were different in age (p=0.001), marital relationship duration (p <0.001), number of pregnancies (p=0.001) and parity (p=0.001). Differences in biochemical measures were observed among the groups: estradiol (p<0.001), FSH (p<0.001), total cholesterol (p=0.001). There were no differences in gait velocity between menopausal status. Values in mean of grip strength decreased by postmenopausal women to perimenopausal and premenopausal ones (24.5 ± 5.1, 25.6 ± 5.4, 26.9 ± 4.9 for post-stage, pre and peri menopausas, respectively, p = 0.02) and the performance of chair stands test was better in premenopausal women compared with that in peri and postmenopausal status (p = 0.02). In multiple linear regression for muscle strength, the variables that remained were: age, estradiol and somatic symptoms measured by Menopause Rating Scale-MRS (R2=0.15). While for the xiv chair-stands test the predictors were number of births and FSH values (R2=0.04). Conclusion: There is a relationship between the stages of menopause and muscle performance in measures of grip strength and sit-up test and these are influenced by the fall of estrogens levels. Data suggest that the decrease in muscle strength and physical performance already appear in the transition to menopause stage, pointing to the need for more research in this area and appropriate preventive interventions

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Population aging is one of the greatest challenges to contemporary public health and, in this perspective, the functional capacity emerges as an important feature in geriatric assessment. The oral health of elderly, in turn, deserves special attention because, historically, in the dental services, this population group was not considered a priority for attention, which is verified by high rates of edentulism found even among these individuals. The present study proposes to examine the relationship between oral health status and functional capacity in an elderly population. To this end, intra-oral epidemiological examination was performed to assess the degree of dental caries, periodontal status, use and need of prosthesis and the presence of lesions. Functional capacity was assessed by the Independence in Activities of Daily Living, which considers the independence or not in the performance of six self-care functions. Socioeconomic and demographic characteristics and general health status were also investigated, in view of the possibility of intervention of these variables in the investigated relation. An factor analysis of the principal components was conducted which resulted four indicators of oral health conditions, representative of the population studied. 441 seniors were enrolled with mean age of 71.7 (± 8.7) years, the majority being female (68%). Functional capacity was dichotomized into completely independent individuals (89.6%) and dependent on at least one of the functions considered (10.4%). There was an association between functional capacity and the indicators related to the presence of many teeth and dental caries, and to that associated with the use and need of prostheses. These associations in turn, lost statistical significance when adjusting for confounding variables, combined in separate models for each indicator. Some of these variables, however, remained associated with functional capacity. It is considered that the study of oral health status of elderly, associeted with the search for an association with functional capacity is important in the construction of indicators necessary for planning preventive and therapeutic interventions that reduce the risk for loss of ability in daily physical functions and their consequences, as the harm in the oral self-care

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The aim of this study was to assess the impact of the Family Health Program (FHP) on a number of oral health indicators in the population of Natal, Brazil. The study is characterized as a quasi-random community intervention trial. The intervention is represented by the implementation of an Oral Health Team (OHT) in the FHP prior to the study. A total of 15 sectors covered by the FHP with OHT were randomly drawn and paired with another 15 sectors, based on socioeconomic criteria, not covered by the teams. A few sectors were lost over the course of the study, resulting in a final number of 22 sectors, 11 covered and 11 not covered. We divided the non-covered areas into two conditions, one in which we considered areas that had some type of assistance program such as the Community Agents Program (CAP), FHP without OHT, BHU (Basic Health Unit) or no assistance, and the other, in which we considered areas that had only BHU or no assistance. Community Health Agents (CHAs) and Dental Office Assistants (DOAs) applied a questionnaire-interview to the most qualified individual of the household and the data obtained per household were transformed into the individual data of 7186 persons. The results show no statistical difference between the oral health outcomes analyzed in the areas covered by OHT in the FHP and in non-covered areas that have some type of assistance program, with a number of indicators showing better conditions in the non-covered areas. When we considered the association between covered and non-covered areas under the second condition, we found a statistical difference in the coverage indicators. Better conditions were found in covered areas for indicators such as I have not been to the dentist in the last year with p < 0.001 and OR of 1.64 and I had no access to dental care with p < 0.001 and OR of 2.22. However, the results show no impact of FHP with OHT on preventive action indicators under both non-covered conditions. This can be clearly seen when we analyze the toothache variable, which showed no significant difference between covered and non-covered areas. This variable is one of the most sensitive when assessing oral health programs, with p of 0.430 under condition 1 and p of 0.038 under condition 2, with CI = 0.70-0.90. In the analysis of health indicators in children where the proportion of deaths in children under age 1, the rate of hospitalization for ARI (Acute Respiratory Infections) in those under age 5 and the proportion of individuals born underweight were considered, a better condition was found in all the outcomes for areas with FHP. Therefore, we can conclude that oral health in the FHP has little effect on oral health indicators, even though the strategy improves the general health conditions of the population, as, for example child health

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A disfunção sexual corresponde a alterações em uma ou mais fases da resposta sexual humana e apresenta maior prevalência na população feminina. Ademais, a participação de alguns fatores como obesidade e níveis dos hormônios esteroidais na disfunção sexual feminina (DSF) permanece incerta. O presente estudo deteve-se na análise da ocorrência de DSF numa população de mulheres portadoras de obesidade, cadastradas no Ambulatório de Cirurgia Bariátrica do Hospital Universitário Onofre Lopes, da Universidade Federal do Rio Grande do Norte, no município de Natal, RN. O estudo foi realizado em uma amostra composta por trinta e uma mulheres, com idade entre 20 e 50 anos, com índice de massa corpórea (IMC) > 30 Kg/m2. A todas as pacientes foi aplicado um questionário composto por uma seção com dados socio-econômicos, e outra abordando a saúde sexual feminina, sendo esta última correspondente ao Female Sexual Function Index (FSFI), para diagnóstico de DSF. A partir dessa caracterização, as pacientes foram reunidas nos grupos CD (pacientes com disfunção, n= 9) e SD (sem disfunção, n= 22). Para a análise do efeito da obesidade na DSF, as pacientes foram reunidas nos grupos 1 (6 pacientes com IMC grau I e II: entre 30 e 40 Kg/m2) e 2 (25 com IMC grau III: acima de 40). Para o estudo da participação dos hormônios esteroidais foram determinadas as concentrações séricas de cortisol, estradiol e dehidroepiandrosterona (DHEA) pelo método de quimiluminescência. A análise estatística dos dados foi realizada usando os testes ANOVA, MANOVA (Pillai), além de análise de Cluster. Para identificar as diferenças entre os domínios do FSFI, foi usado o teste T de Student. A significância considerada para todos os testes foi para p< 0,01. Das pacientes estudadas, 25,8% apresentaram DSF de acordo com o escore total do FSFI. A análise estatística posterior evidenciou que as diferenças ocorreram para os domínios desejo, excitação e orgasmo. Não foi encontrada relação da presença de DSF com os diferentes graus de obesidade ou com os níveis hormonais dos esteróides cortisol, estradiol ou DHEA. Contudo, foi encontrado aumento significativo nos níveis séricos de estradiol para o grupo 1, que corresponde ao de menor índice de IMC. Estes resultados mostram que a prevalência de DSF não diferiu entre os graus I,II e III de obesidade das pacientes deste estudo mas, quando presente, a disfunção ocorre nos domínios desejo, excitação e orgasmo. A maior concentração de estradiol encontrada nas pacientes de menor índice de IMC sugere uma possível relação entre as duas variáveis que precisa ser investigada em estudos futuros.