Efeitos Agudos da Bebida Energética sobre Parâmetros Autonômicos e Cardiovasculares em Indivíduos com Diferentes Capacidades Cardiorrespiratórias: Um Ensaio Controlado, Randomizado, Crossover e Duplo Cego / Acute Effects of Energy Drink on Autonomic and Cardiovascular Parameters Recovery in Individuals with Different Cardiorespiratory Fitness: A Randomized, Crossover, Double-Blind and Placebo-Controlled Trial

Resumo Fundamento Tem-se sugerido que o consumo de bebidas energéticas (BEs) possa afetar a atividade cardiovascular. Objetivos Investigar os efeitos agudos da ingestão de BE sobre a variabilidade da frequência cardíaca (VFC) recuperação cardiovascular após exercício aeróbico moderado em homens de diferentes capacidades cardiorrespiratórias. Métodos Este é um estudo randomizado, duplo cego, crossover, controlado por placebo. Vinte e oito jovens adultos foram divididos em dois grupos de acordo com o pico de consumo de oxigênio (pico de VO2): (1) pico de VO2 alto (AO) - pico de VO2 > 52,15 mL/Kg/min, e (2) pico de VO2 baixo (BO) - pico de VO2 <52,15 mL/Kg/min. Os indivíduos de ambos os grupos foram submetidos a dois protocolos de exercícios em ordem aleatória: exercício moderado aeróbico (60% de pico de VO2) após a ingestão de 250 mL de água (protocolo placebo) ou 250 mL de BE (protocolo BE). Durante os testes de exercício, foram registrados valores de parâmetros cardiorrespiratórios e de VFC. Resultados Foram observadas diferenças significativas para o índice de LF (unidades normalizadas) entre "repouso" e "Rec1" nos grupos de AO e BO durante o protocolo BE. Para a razão LF/HF, foram observadas diferenças significativas entre "repouso" e Rec1 nos grupos AO e BO nos protocolos BE. Conclusão A ingestão aguda de BE retardou a recuperação da frequência cardíaca após o exercício em indivíduos com capacidade cardiorrespiratória baixa e indivíduos com capacidade cardiorrespiratória alta.

Abstract Background It has been suggested that the consumption of energy drinks (ED) may affect cardiovascular activity. Objectives to investigate the acute effects of ED intake on heart rate variability (HRV) and cardiovascular recovery after moderate aerobic exercise in males with different cardiorespiratory capacities. Methods This is a randomized, double-blind, crossover, placebo-controlled study. Twenty-eight young adults were split into two groups according to their peak oxygen consumption (VO2peak) values: (1) High VO2 peak (HO) - VO2 peak > 52.15 mL/kg/min, and (2) low VO2 peak (LO) - peak VO2 <52.15 mL/kg/min. Subjects of both groups underwent two exercise protocols in randomized order: moderate aerobic exercise (60% of VO2peak) following the intake of 250 mL of water (placebo protocol) or 250 mL of ED (ED protocol). During the exercise tests, values of cardiorespiratory and HRV parameters were recorded. Results Significant differences were observed for the LF (normalized units) index between rest and Rec1 in HO energy and LO groups during the ED protocol. For the LF/HF ratio, significant differences were seen between rest and Rec1 in HO and LO during ED protocols. Conclusion Acute ED intake delayed heart rate recovery after exercise in subjects with low and high cardiorespiratory fitness.

Risk of cardiovascular disease in soccer referees: a cross sectional study

Introducrion: although the mortality rate among soccer players is low, it causes much impact on the entire community and is a fascinating conundrum. Objetive: to evaluate the cardiovascular risk of soccer referees, to describe the frequency of cardiovascular risk considering age groups younger and older than 35 years old and to relate the Framingham and PROCAM indices for the comparison of cardiovascular risk in soccer referees. Methods: We analyzed 50 referees of Paulista Soccer Federation subjected to clinical and laboratory based evaluations at the Center for Sports Health at the Faculty of Medicine of ABC, and were divided into two groups: lower and higher than 35 years of age. For analysis involving all variables of the study it was initially carried out as a descriptive evaluation of the entire group, and then the Framingham and PROCAM methods were applied in a two-dimensional way. Finally, the logistic regression analysis was applied. Anthropometric statistics, blood pressure, laboratory tests and ergospirometric values were within normal limits. Results: referees older than 35 years old presented significant increased values of waist circumference, body mass index, glucose blood levels, lower VO2max and higher cardiovascular risk according to Framingham and PROCAM. Conclusion: the risk for coronary heart disease was higher in referees older than 35 years old.

Introdução: embora a taxa de mortalidade entre os jogadores de futebol seja baixa, ela causa muito impacto em toda a comunidade e é um enigma fascinante.Objetivo: avaliar o risco cardiovascular de árbitros de futebol, descrever a frequência de risco cardiovascular considerando faixas etárias menores e maiores de 35 anos e relacionar os índices de Framingham e PROCAM para comparação de risco cardiovascular em árbitros de futebol.Métodos: foram analisados 50 árbitros da Federação Paulista de Futebol submetidos a avaliações clínicas e laboratoriais no Centro de Saúde Esportiva da Faculdade de Medicina do ABC, divididos em dois grupos: menores e maiores de 35 anos. Para a análise envolvendo todas as variáveis do estudo foi realizada inicialmente como uma avaliação descritiva de todo o grupo e, em seguida, foram aplicados os métodos de Framingham e PROCAM de forma bidimensional. Por fim, foi aplicada a análise de regressão logística. Estatísticas antropométricas, pressão arterial, exames laboratoriais e valores ergoespirométricos estavam dentro da normalidade.Resultados: os árbitros com mais de 35 anos apresentaram valores significantemente aumentados de circunferência da cintura, índice de massa corporal, glicemia, menor VO2máx e maior risco cardiovascular segundo Framingham e PROCAM.Conclusão: o risco de doença coronariana foi maior em árbitros com mais de 35 anos.

A Versatile Nanocarrier-Cubosomes, Characterization, and Applications.

The impact of nanotechnology on the exponential growth of several research areas, particularly nanomedicine, is undeniable. The ability to deliver active molecules to the desired site could significantly improve the efficiency of medical treatments. One of the nanocarriers developed which has drawn researchers' attention are cubosomes, which are nanosized dispersions of lipid bicontinuous cubic phases in water, consisting of a lipidic interior and aqueous domains folded in a cubic lattice. They stand out due to their ability to incorporate hydrophobic, hydrophilic, and amphiphilic compounds, their tortuous internal configuration that provides a sustained release, and the capacity to protect and safely deliver molecules. Several approaches can be taken to prepare this structure, as well as different lipids like monoolein or phytantriol. This review paper describes the different methods to prepare nanocarriers. As it is known, the physicochemical properties of nanocarriers are very important, as they influence their pharmacokinetics and their ability to incorporate and deliver active molecules. Therefore, an extensive characterization is essential to obtain the desired effect. As a result, we have extensively described the most common techniques to characterize cubosomes, particularly nanocarriers. The exceptional properties of the cubosomes make them suitable to be used in several applications in the biomedical field, from cancer therapeutics to imaging, which will be described. Taking in consideration the outstanding properties of cubosomes, their application in several research fields is envisaged.

In Vitro CRISPR/Cas9 Transfection and Gene-Editing Mediated by Multivalent Cationic Liposome-DNA Complexes.

Clustered regularly interspaced short palindromic repeats (CRISPR) and CRISPR-associated nuclease 9 (Cas9) gene-editing offers exciting new therapeutic possibilities for disease treatment with a genetic etiology such as cancer, cardiovascular, neuronal, and immune disorders. However, its clinical translation is being hampered by the lack of safe, versatile, and effective nonviral delivery systems. Herein we report on the preparation and application of two cationic liposome−DNA systems (i.e., lipoplexes) for CRISPR/Cas9 gene delivery. For that purpose, two types of cationic lipids are used (DOTAP, monovalent, and MVL5, multivalent with +5e nominal charge), along with three types of helper lipids (DOPC, DOPE, and monoolein (GMO)). We demonstrated that plasmids encoding Cas9 and single-guide RNA (sgRNA), which are typically hard to transfect due to their large size (>9 kb), can be successfully transfected into HEK 293T cells via MVL5-based lipoplexes. In contrast, DOTAP-based lipoplexes resulted in very low transfection rates. MVL5-based lipoplexes presented the ability to escape from lysosomes, which may explain the superior transfection efficiency. Regarding gene editing, MVL5-based lipoplexes achieved promising GFP knockout levels, reaching rates of knockout superior to 35% for charge ratios (+/−) of 10. Despite the knockout efficiency being comparable to that of Lipofectamine 3000® commercial reagent, the non-specific gene knockout is more pronounced in MVL5-based formulations, probably resulting from the considerable cytotoxicity of these formulations. Altogether, these results show that multivalent lipid-based lipoplexes are promising CRISPR/Cas9 plasmid delivery vehicles, which by further optimization and functionalization may become suitable in vivo delivery systems.

pH-sensitive nanoliposomes for passive and CXCR-4-mediated marine yessotoxin delivery for cancer therapy.

Background: Yessotoxin (YTX), a marine-derived drug, was encapsulated in PEGylated pH-sensitive nanoliposomes, covalently functionalized (strategy I) with SDF-1α and by nonspecific adsorption (strategy II), to actively target chemokine receptor CXCR-4. Methods: Cytotoxicity to normal human epithelial cells (HK-2) and prostate (PC-3) and breast (MCF-7) adenocarcinoma models, with different expression levels of CXCR-4, were tested. Results: Strategy II exerted the highest cytotoxicity toward cancer cells while protecting normal epithelia. Acid pH-induced fusion of nanoliposomes seemed to serve as a primary route of entry into MCF-7 cells but PC-3 data support an endocytic pathway for their internalization. Conclusion: This work describes an innovative hallmark in the current marine drug clinical pipeline, as the developed nanoliposomes are promising candidates in the design of groundbreaking marine flora-derived anticancer nanoagents.

Autonomic modulation at rest and in response to postural change in adolescents with Duchenne muscular dystrophy: a cross-sectional study / Modulação autonômica em repouso e em resposta a mudanças posturais em adolescentes com distrofia muscular de Duchenne: um estudo transversal

ABSTRACT Background: Analysis of autonomic modulation after postural change may inform the prognosis and guide treatment in different populations. However, this has been insufficiently explored among adolescents with Duchenne muscular dystrophy (DMD). Objective: To investigate autonomic modulation at rest and in response to an active sitting test (AST) among adolescents with DMD. Methods: Fifty-nine adolescents were included in the study and divided into two groups: 1) DMD group: adolescents diagnosed with DMD; 2) control group (CG): healthy adolescents. Participants' weight and height were assessed. Lower limb function, motor limitations and functional abilities of the participants in the DMD group were classified using the Vignos scale, Egen classification and motor function measurement, respectively. The following variables were assessed before, during and after AST: systolic blood pressure (SBP), diastolic blood pressure (DBP), respiratory rate (f), oxygen saturation and heart rate (HR). To analyze the autonomic modulation, the HR was recorded beat-by-beat. Heart rate variability (HRV) indices were calculated in the time and frequency domains. Results: Differences in relation to groups were observed for all HRV indices, except LF/HF, oxygen saturation, HR and f (p < 0.05). Differences in relation to time and the interaction effect between group and time were observed for RMSSD, SD1, SD2, SD1/SD2, LFms2 and LFnu, HFun, SBP and DBP (p < 0.05). Differences in relation to time were also observed for the indice SDNN, FC and f (p < 0.05). Conclusions: Performing the AST promoted reduced autonomic modulation and increased SBP, DBP and HR in adolescents with DMD.

Resumo Antecedentes: A análise da modulação autonômica após mudanças posturais pode gerar informações prognósticas e orientar o tratamento em diferentes populações. Porém, isso não foi suficientemente explorado em adolescentes com DMD. Objetivo: Investigar a modulação autonômica em repouso e em resposta ao teste ativo sentado (TAS) em adolescentes com DMD. Métodos: 59 adolescentes foram incluídos no estudo e divididos em dois grupos: 1) Grupo DMD: adolescentes com diagnóstico de DMD; 2) Grupo controle: adolescentes saudáveis. O peso e a altura dos participantes foram avaliados. No grupo DMD, a funcionalidade de membros superiores, limitações motoras, e habilidades funcionais foram classificadas pela escala de Vignos, Egen Klassification, e motor function measure respectivamente. Pressão arterial sistólica (PAS), pressão arterial diastólica (PAD), frequência respiratória (f), saturação de oxigênio, e frequência cardíaca (FC) foram avaliadas em repouso, durante e após o TAS. Para analisar a modulação autonômica, a FC foi registrada batimento a batimento. Os índices de variabilidade da frequência cardíaca (VFC) foram calculados nos domínios do tempo e da frequência. Resultados: Diferenças entre os grupos foram observadas para todos os índices da VFC, exceto LF/HF, saturação de oxigênio, FC e f (p<0,05). Diferenças em relação ao tempo e interação entre grupo e tempo foram observadas para RMSSD, SD1, SD2, SD1/SD2, LFms2, LFun, HFnu, SBP e DBP (p<0,05). Diferenças em relação ao tempo foram também observadas para o índice SDNN, FC e f (p<0,05). Conclusões: A realização do TAS promoveu redução da modulação autonômica e aumento da PAS, PAD e FC em adolescentes com DMD.

Effect of air pollution on the autonomic modulation of heart rate in overweight adults / Efeito da poluição atmosférica na modulação autonômica da frequência cardíaca em indivíduos com excesso de peso

ABSTRACT Objective: To analyze the effect of air pollution on heart rate variability in overweight individuals. Methods: A total of 46 adult individuals, both sexes, aged between 18 and 49 years and with body mass index >25kg/m2 were analyzed. All volunteers were students from public schools of two cities in the state of São Paulo. The clinical, demographic and anthropometric data of each individual, as well as heart rate variability through time domain, geometric and frequency indices were collected. For the air quality analysis, the following variables were investigated: concentration of carbon dioxide, particulate matter, temperature and relative humidity. The analysis was carried out with descriptive and analytical statistics, adopting a level of significance of 5%. Results: There was a reduction in overall heart rate variability in overweight individuals by the following indices: mean standard deviation of all normal RR intervals, long-term standard deviation of continuous RR intervals, ratio of short-and long-term standard deviation of continuous RR intervals. In addition, the indices responsible for parasympathetic control showed a downward trend in their values, as well as the low frequency index, which represented sympathetic action, although not significant. Conclusion: Overweight individuals exposed to air pollution had lower heart rate variability than the Control Group.

RESUMO Objetivo: Analisar o efeito da poluição atmosférica na variabilidade da frequência cardíaca em indivíduos com excesso de peso. Métodos: Foram analisados 46 indivíduos adultos, de ambos os sexos, com idade entre 18 e 49 anos e índice de massa corporal >25kg/m2. Todos os voluntários eram estudantes da Educação de Jovens e Adultos em duas cidades do estado de São Paulo. Foram coletadas informações clínicas, demográficas e antropométricas de cada indivíduo, bem como a variabilidade da frequência cardíaca, por meio dos índices do domínio do tempo, geométricos e de frequência. Para a análise da qualidade do ar, foram investigadas as variáveis concentração de dióxido de carbono, material particulado, temperatura e umidade do ar. A análise se deu por estatística descritiva e analítica, adotando-se nível de significância de 5%. Resultados: Ocorreu redução na variabilidade da frequência cardíaca geral nos indivíduos com excesso de peso por meio dos índices geométricos (desvio padrão a longo prazo dos intervalos RR contínuos, e a razão entre as variações curta e longa dos intervalos RR) e o domínio do tempo (desvio padrão da média de todos os intervalos RR normais). Índices responsáveis pelo controle parassimpático mostraram-se com tendência de queda em seus valores, bem como o índice de baixa frequência que representava a ação do simpático, embora com valores não significativos. Conclusão: Indivíduos com excesso de peso expostos à poluição atmosférica apresentaram menor variabilidade da frequência cardíaca em comparação ao Grupo Controle.

Secondary particles formed from the exhaust of vehicles using ethanol-gasoline blends increase the production of pulmonary and cardiac reactive oxygen species and induce pulmonary inflammation.

BACKGROUND: Ethanol vehicles release exhaust gases that contribute to the formation of secondary organic aerosols (SOA). OBJECTIVE: To determine in vivo toxicity resulting from exposure to SOA derived from vehicles using different ethanol-gasoline blends (E0, E10, E22, E85W, E85S, E100). METHODS: Exhaust emissions from vehicles using ethanol blends were delivered to a photochemical chamber and reacted to produce SOA. The aerosol samples were collected on filters, extracted, and dispersed in an aqueous solutions and intratracheally instilled into Sprague Dawley rats in doses of 700 µg/0.2 ml. After 45 min and 4 h pulmonary and cardiac chemiluminescence (CL) was measured to estimate the amount of reactive oxygen species (ROS) produced in the lungs and heart. Inflammation was measured by differential cell count in bronchoalveolar lavages (BAL). RESULTS: Statistically and biologically significant differences in response to secondary particles from the different fuel formulations were detected. Compared to the control group, animals exposed to SOA from gasoline (E0) showed a significantly higher average CL in the lungs at 45 min. The highest CL averages in the heart were observed in the groups exposed to SOA from E10 and pure ethanol (E100) at 45 min. BAL of animals exposed to SOA from E0 and E85S had a significant increased number of macrophages at 45 min. BAL neutrophil count was increased in the groups exposed to E85S (45 min) and E0 (4 h). Animals exposed to E0 and E85W had increased BAL lymphocyte count compared to the control and the other exposed groups. DISCUSSION: Our results suggest that SOA generated by gasoline (E0), followed by ethanol blends E85S and E85W, substantially induce oxidative stress measured by ROS generation and pulmonary inflammation measured by the recruitment of white blood cells in BAL.

Correction to: Reply to the letter "Cardiac autonomic evaluation in breast cancer patients: role of cytokines and heart rate recovery".

Unfortunately, errors occurred in the original article.

Cardiac autonomic modulation impairments in advanced breast cancer patients.

AIM: To compare cardiac autonomic modulation in early- versus advanced-stage breast cancer patients before any type of cancer treatment and investigate associated factors. METHODS AND RESULTS: This cross-sectional study included women (30-69 years old) with primary diagnosis of breast cancer and women with benign breast tumors. We evaluated cardiac modulation by heart rate variability and assessed factors of anxiety, depression, physical activity, and other relevant medical variables. Patients were divided into three groups based on TNM staging of cancer severity: early-stage cancer (n = 42), advanced-stage cancer (n = 37), or benign breast tumors to serve as a control (n = 37). We analyzed heart rate variability in time and frequency domains. The advanced-stage cancer group had lower vagal modulation than early-stage and benign groups; also, the advance-stage group had lower overall heart rate variability when compared to benign conditions. Heart rate variability was influenced by age, menopausal status, and BMI. CONCLUSIONS: Heart rate variability seems to be a promising, non-invasive tool for early diagnosis of autonomic dysfunction in breast cancer and detection of cardiovascular impairments at cancer diagnosis. Cardiac autonomic modulation is inversely associated with breast cancer staging.

Effects of water ingestion throughout exercise and recovery on cardiac autonomic modulation during and after exercise

Purpose: To analyze the effects of water intake on heart rate variability (HRV) during and after exercise. Methods: Thirty-one young males performed three different procedures: I) a maximal exercise test to determine the load for the protocols; II) the control protocol (CP); III) the experimental protocol (EP). The protocols comprised 10 minutes at rest, 90 minutes of treadmill exercise (60% of VO2 peak), and 60 minutes of recovery. No rehydration beverage consumption was allowed during the CP. During the EP, the participants were given water every 15 minutes, being that the amount of water to be ingested by each volunteer was divided over the time of exercise and recovery. For the analysis of HRV data, time and frequency domain indices were investigated in the following moments (M): M1 (5 minutes final of rest), M2 (25-30 minutes of exercise), M3 (55-60 minutes of exercise), M4 (85-90 minutes of exercise), M5 (5-10 minutes of recovery), M6 (15-20 minutes of recovery), M7 (25-30 minutes of recovery), M8 (40-45 minutes of recovery), and M9 (55-60 minutes of recovery). Results: There was no statistically significant difference between the groups that were examined during the exercise. HRV values for the CP and EP at the end of the exercise period were as follows SDNN (5.95±1.89 vs 6.89±2.11); RMSSD (3.29±0.78 vs 3.39±0.95); HF [nu] (24.06±14.26 vs 19.10±11.94); LF [nu] (75.93±14.26 vs 80.89±11.94); HF [ms2] (0.90±1.16 vs 0.94±0.89); LF [ms2] (4.65±5.94 vs 5.35±5.09); and LF/HF ratio (4.64±3.15 vs 6.95±5.57). HRV values for the CP and the EP at the end of the recovery period were as follows: SDNN (39.63±19.63 vs 49.95±17.79); RMSSD (21.63±15.55 vs 36.43±22.73); HF [ms2] (285.51±392.27 vs 699.29±699.66); LF [nu] (74.55±13.25 vs 61.19±19.27); and HF [nu] (25.44±13.25 vs 38.8±19.27). Conclusion: The hydration with water was not enough to significantly influence the linear HRV indices during exercise; however, it promoted faster recovery of these variables after exercise

Symbolic analysis of heart rate variability and its interaction with p-value of normality tests applied on RR intervals / Análise simbólica da variabilidade da frequência cardíaca e sua interação com valor-p de testes de normalidade aplicado em intervalos RR

OBJECTIVE: A previous study suggested that the p-value of normality test applied to RR intervals is an index able to quantify Heart Rate Variability (HRV) through correlation of traditional time and frequency domain indices. We investigate the association between the p-value of normality test applied in RR intervals and symbolic analysis of HRV. METHOD: We evaluated 32 healthy women between 18 and 30 years old. RR intervals were used for HRV analysis and we performed symbolic analysis, where RR intervals are joined by symbols. Sets of three consecutive symbols (RR intervals) were grouped into four types of clusters, as follows: 1. Three equal symbols (zero variation); 2: two equal, one divergent symbol (one variation); 3. Three different symbols monotonically ascending or descending (two like variations); 4. Three different symbols, forming a peak or a trough (two unlike variations). Frequency of occurrence of each type of cluster was calculated. Normality tests were applied to all RR intervals and the p-value was calculated. We computed the correlations between the p-value of normality test and symbolic analysis of HRV. RESULTS: Correlation coefficients between the p-value of normality test from Kolmorogov-Smirnov test and the four types of clusters showed no correlation for any of them. Likewise, the correlation coefficient index between the p-value of normality test calculated from the Shapiro-Wilk test and symbolic analysis produced no significant results for any of the four types of clusters. CONCLUSION: There was no significant correlation between the p-value of normality test and HRV symbolic analysis. The physiological significance of this result is that the PNT is not related to chaotic behavior of HRV.

OBJETIVO: Um estudo anterior sugeriu que o valor "p" do teste de normalidade (PNT) aplicado a intervalos RR é um índice capaz de quantificar variabilidade da frequência cardíaca através da correlação tradicional dos índices de tempo e frequência. Investigamos a associação entre o teste PNT aplicado a intervalos RR e a análise simbólica da variabilidade da frequência cardíaca. MÉTODO: Foram avaliadas 32 mulheres saudáveis entre 18 e 30 anos de idade. Os intervalos RR foram utilizados para análise da variabilidade da frequência cardíaca; foi realizada uma análise simbólica, onde intervalos RR são unidos por símbolos. Grupos de três símbolos consecutivos foram agrupados em quatro tipos de aglomerados, a saber: 1: três símbolos iguais (variação zero); 2: dois símbolos iguais, um divergente (uma variação); 3: três símbolos diferentes, monotonicamente crescentes ou decrescentes (duas variações iguais); 4: três símbolos diferentes, formando um pico ou uma calha (duas variações desiguais). Foi calculada a frequência de ocorrência de cada tipo de cluster. Testes de normalidade foram aplicados a todos os intervalos RR e o valor de "p" foi calculado. Calculamos as correlações entre o PNT e análise simbólica de HRV. RESULTADOS: Os coeficientes de correlação entre PNT de teste Kolmorogov-Smirnov e os quatro tipos de clusters não mostraram correlação com qualquer um deles. Da mesma forma, o coeficiente de correlação entre o índice PNT calculado a partir do teste de Shapiro-Wilk e a análise simbólica não produziu resultados significativos para qualquer dos quatro tipos de aglomerados. CONCLUSÃO: Não houve correlação significativa entre o PNT e análise simbólica da variabilidade da frequência cardíaca. O significado fisiológico deste resultado é que o PNT não está relacionado ao comportamento caótico da VFC.

Heart rate variability measure in breast cancer patients and survivors: A systematic review.

PURPOSE: In the current study, we aimed to review literature findings showing the clinical importance of cardiac autonomic modulation assessed by heart rate variability analysis in breast cancer (BC) patients and survivors. METHODS: We conducted a systematic review according to The PRISMA Statement in Medline, Scopus and Web of Science (_-2015) databases. The search was limited to articles in English language, published in peer-reviewed journals, and with adult age samples only (e.g., women, patients, or survivors, diagnosed with BC in any stage). We included observational studies and randomized trials. Detailed heart rate variability analysis (instruments, data collection protocol, and analysis methods) was required. Search terms included autonomic nervous system, heart rate variability, sympathetic and parasympathetic nervous system, autonomic dysfunction, vagal nervous and breast neoplasms, breast cancer and breast tumor. RESULTS: Twelve studies were included in this review. The clinical importance of cardiac autonomic modulation assessed by heart rate variability analysis in BC patients and survivors is demonstrated by association with effects of BC surgery, and treatments, and the adverse effects of surgery and treatments on survivors (e.g., cardiotoxicity, fatigue, and stress). LIMITATIONS: The strength of evidence of included studies is low: small samples size and heterogeneity, presence of confounders, and observational studies design. CONCLUSIONS: The heart rate variability analysis could be used as a complementary non-invasive tool for the early diagnosis and better prognosis of autonomic dysfunction, and survival in BC patients. There are many potential clinical applications of heart rate variability analysis in BC patients, and the employment of such approaches could lead to lower impairment of autonomic function in this individuals.

Higuchi fractal dimension applied to RR intervals in children with Attention Deficit Hyperactivity Disorder

BACKGROUND: Attention deficit hyperactivity disorder (ADHD) is categorized by a lowered attention span, recklessness, and hyperactivity. Autonomic nervous system inequality has previously been studied using the same data by chaotic global techniques. We aim to compare the autonomic function of children with ADHD and controls by analyzing heart rate variability (HRV) METHODS: 28 children with ADHD (22 boys, mean age 10.0 years ± 1.9 years) and 28 controls (15 boys, mean age 9.9 years ± 1.8 years) rested in supine position with spontaneous breathing for 20 minutes. Heart rate was recorded beat by beat. HRV analysis was performed by Higuchi Fractal Dimension technique. RESULTS: ADHD promoted an increase in the Higuchi Fractal Dimension. The optimum value of Kmax was 10. CONCLUSION: ADHD significantly altered cardiac autonomic modulation as measured by the Higuchi fractal dimension of HRV. It can therefore be stated that ADHD has increased the complexity of the HRV signal through cardiac autonomic modulation.

INTRODUÇÃO: O transtorno de deficit de atenção e hiperatividade (TDAH) é caracterizado por um período reduzido de atenção, impulsividade e hiperatividade. O desequilíbrio na função do sistema nervoso autônomo (SNA) tem sido previamente estudado utilizando-se técnicas globais da teoria do caos. OBJETIVO: comparar a função autonômica de crianças com TDAH e controles por meio da análise da variabilidade da frequência cardíaca (VFC) MÉTODO: 28 crianças com TDAH (22 meninos, com média de idade de 10,0 anos ± 1,9 anos) e 28 controles (15 meninos, com média de idade de 9,9 anos ± 1,8 anos) permaneceram em decúbito dorsal, com respiração espontânea por 20 minutos. A frequência cardíaca foi registrada batimento a batimento e a análise da VFC foi realizada pela técnica de Dimensão Fractal Higuchi. RESULTADOS: TDAH promoveu um aumento na Dimensão Fractal Higuchi. O valor ideal de Kmax foi 10. CONCLUSÃO: O TDAH alterou significantemente a modulação autonômica cardíaca, como demonstrado pela Dimensão Fractal Higuchi da VFC. Assim, pode-se afirmar que crianças com TDAH apresentaram aumento das respostas caóticas neste tipo de análise da modulação autonômica cardíaca.

Efeitos de um programa multidisciplinar sobre a modulação autonômica de crianças e adolescentes com sobrepeso e obesidade / Effects of a multidisciplinary program on autonomic modulation in overweight or obese children and adolescents

PURPOSE: this study evaluated the effects of a multidisciplinary program on autonomic modulation in overweight or obese children and adolescents. METHODS: fifteen individuals with 10,93 ± 2,28 years were submitted to autonomic evaluation using heart rate variability before and after a program based on physical exercises for three months, three times a week, 60 minutes per session and psychological and nutritional counseling. Data was analyzed using the paired t-test or Wilcoxon test and the level of significance was set at P < 0.05. RESULTS: multidisciplinary program was able to promote benefits in autonomic modulation observed thought temporal (SDNN: 39,96 ± 10,33 x 49,44 ± 12,31; p = 0,019; rMSSD: 28,97 ± 11,50 x 37,26 ± 11,17; p = 0,018), spectral (LFnu: 64,49 ± 12,21 x 56,74 ± 11,18; p = 0,014; HFnu: 35,50 ± 12,21 x 43,25 ± 11,18; p = 0,014) and geometrical (SD1: 20,51 ± 8,13 x 26,36 ± 7,90; p = 0,018 SD2: 52,31 ± 13,04 x 64,58 ± 16,33; p = 0,031) indices in overweigh and obese children and adolescents. Also, after the intervention there was a reduction on resting heart rate (88,53 ± 9,24 x 83,09 ± 7,93; p = 0,023) and there were changes in the classification of overweigh 26,67% x 46,66% and obesity 73,33% x 53,33%, although not significant changes in body mass index. CONCLUSIONS: exercise program together with nutritional and psychological counseling is able to promote benefits in autonomic modulation in children and adolescents who are overweight or obese.

OBJETIVO: avaliar a influência de um programa multidisciplinar na modulação autonômica de crianças e adolescentes com sobrepeso e obesidade. MÉTODO: quinze indivíduos com 10,93 ± 2,28 anos foram submetidos a avaliação da modulação autonômica por meio da variabilidade da frequência cardíaca antes e após um programa de atividades físicas conduzido por três meses, com frequência de três vezes na semana por 60 minutos cada sessão, associado com aconselhamento nutricional e psicológico. Para análise estatística foi utilizado teste T para dados pareados ou teste de Wilcoxon com significância de p < 0,05. RESULTADOS: o programa multidisciplinar foi capaz de influenciar positivamente a modulação autonômica o que pode ser observado por índices temporais (SDNN = 39,96 ± 10,33 vs. 49,44 ± 12,31; p = 0,019; rMSSD = 28,97 ± 11,50 vs. 37,26 ± 11,17; p = 0,018), espectrais (LFnu = 64,49 ± 12,21 vs. 56,74 ± 11,18; p = 0,014; HFnu = 35,50 ± 12,21 vs. 43,25 ± 11,18; p = 0,014) e geométricos (SD1 = 20,51 ± 8,13 vs. 26,36 ± 7,90; p = 0,018; SD2 = 52,31 ± 13,04 vs. 64,58 ± 16,33; p = 0,031) de variabilidade em crianças e adolescentes com sobrepeso e obesidade. Adicionalmente, após a intervenção houve redução da frequência cardíaca de repouso (88,53 ± 9,24 vs. 83,09 ± 7,93; p = 0,023) e mudanças na classificação da obesidade dos indivíduos para sobrepeso 26,67% vs. 46,66% e obesidade 73,33% vs. 53,33%. Apesar disso, não houve diferença significante no índice de massa corporal. CONCLUSÕES: um programa de exercícios associado com aconselhamento nutricional e psicológico foi capaz de promover benefícios na modulação autonômica em crianças e adolescentes com sobrepeso e obesidade.

A single bout of exercise with a flexible pole induces significant cardiac autonomic responses in healthy men

OBJECTIVES: Flexible poles can provide rapid eccentric and concentric muscle contractions. Muscle vibration is associated with a "tonic vibration reflex” that is stimulated by a sequence of rapid muscle stretching, activation of the muscle spindles and stimulation of a response that is similar to the myotatic reflex. Literature studies analyzing the acute cardiovascular responses to different exercises performed with this instrument are lacking. We investigated the acute effects of exercise with flexible poles on the heart period in healthy men. METHOD: The study was performed on ten young adult males between 18 and 25 years old. We evaluated the heart rate variability in the time and frequency domains. The subjects remained at rest for 10 min. After the rest period, the volunteers performed the exercises with the flexible poles. Immediately after the exercise protocol, the volunteers remained seated at rest for 30 min and their heart rate variability was analyzed. RESULTS: The pNN50 was reduced at 5-10 and 15-20 min after exercise compared to 25-30 min after exercise (p = 0.0019), the SDNN was increased at 25-30 min after exercise compared to at rest and 0-10 min after exercise (p = 0.0073) and the RMSSD was increased at 25-30 min after exercise compared to 5-15 min after exercise (p = 0.0043). The LF in absolute units was increased at 25-30 min after exercise compared to 5-20 min after exercise (p = 0.0184). CONCLUSION: A single bout of exercise with a flexible pole reduced the heart rate variability and parasympathetic recovery was observed approximately 30 min after exercise. .

Integrative aspects of the relationship between stress and heart rate variability / Aspectos integrativos da relação entre o estresse e a regulação autonômica cardíaca

The literature indicates stress as a response of the organism to a stimulation that requires enormous efforts to adapt to the changes in the environment and the body. When an individual is subjected to stress, the autonomic nervous system is triggered, the sympathetic pathway is activated, and the parasympathetic system is suppressed, which exerts several effects on the cardiovascular system and affects heart rate variability. This research aimed to conduct a literature review to find andanalyze the studies that address clearly the implications of stress on heart rate variability. The methodology employed was an active search in the databases SciELO, PubMed and Lilacs. The results were five articles, most of which suggest a relationship between stress and heart rate variability. We observed that the majority of the studies indicated a strong association between stress and cardiac autonomic activity. The stress is present in the daily activities of the population, especially in labor. The subject is vast, however, were observed in the references the effects of stress on the body making it vulnerable to diseases. Thus, this information may contributeto the aid of preventive strategies against stress and diseases of the cardiovascular system.

A literatura mostra que o estresse é uma resposta do organismo frente a um estímulo que o impõe a produzir um esforço mais elevado para se adaptar às circunstâncias que estão ocorrendo, tanto no ambiente como no organismo. Quando um indivíduo é submetido a tensão, o sistema nervoso autônomo é disparado, ativando a via simpática e o sistema parassimpático é suprimida, exercendo vários efeitos sobre o sistema cardiovascular e atingindo a variabilidade da frequência cardíaca. A presente pesquisa teve por objetivo realizar uma revisão de literatura, a fim de encontrar e analisar estudos que abordem de forma clara as implicações do estresse sobre a variação da frequência cardíaca. O método empregado foi uma busca ativa nas bases de dados SciELO, Lilacs e PubMed. Os resultados encontrados foram de cinco trabalhos, cuja maioria sugere uma relação entre o estresse e variações da frequência cardíaca. A maioria dos estudos demonstrou uma associação entre estresse e a atividade autonômica cardíaca. O estresse está presente nas atividades cotidianas da população, principalmente nas laborais. O assuntoé vasto, porém, foram observados nas referências os efeitos doestresse sobre o organismo, tornando-o vulnerável a doenças. Assim,essas informações podem contribuir para o auxílio de estratégiaspreventivas ao estresse e a patologias do sistema cardiovascular.