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1.
Nano Lett ; 24(19): 5920-5928, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38708934

RESUMO

A significant challenge in direct seawater electrolysis is the rapid deactivation of the cathode due to the large scaling of Mg(OH)2. Herein, we synthesized a Pt-coated highly disordered NiCu alloy (Pt-NiCu alloy) electrode with superior solidophobic behavior, enabling stable hydrogen generation (100 mA cm-2, >1000 h durability) and simultaneous production of Mg(OH)2 (>99.0% purity) in electrolyte enriched with Mg2+ and Ca2+. The unconventional solidophobic property primarily stems from the high surface energy of the NiCu alloy substrate, which facilitates the adsorption of surface water and thereby compels the bulk formation of Mg(OH)2 via homogeneous nucleation. The discovery of this solidophobic electrode will revolutionarily simplify the existing techniques for seawater electrolysis and increase the economic viability for seawater electrolysis.

2.
Am J Obstet Gynecol MFM ; 6(4): 101338, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38453019

RESUMO

BACKGROUND: In nonpregnant individuals, the rate-pressure product, the product of heart rate and systolic blood pressure, is used as a noninvasive surrogate of myocardial O2 consumption during cardiac stress testing. Pregnancy is considered a physiological cardiovascular stress test. Evidence describing the impact of pregnancy on myocardial O2 demand, as assessed by the rate-pressure product, is limited. OBJECTIVE: This study aimed to describe changes in the rate-pressure product for each pregnancy trimester, during labor and delivery, and the postpartum period among low-risk pregnancies. STUDY DESIGN: This was a retrospective cohort study that assessed uncomplicated pregnancies delivered vaginally at term. We collected rate-pressure product (heart rate × systolic blood pressure) values preconception, during pregnancy for each trimester (at ≤13 weeks + 6/7 days, at 14 weeks + 0/7 days through 27 weeks + 6/7 days, and at ≥28 weeks + 0/7 days), during the labor and delivery encounter (hospital admission until complete cervical dilation, complete cervical dilation until placental delivery, and after placental delivery until hospital discharge), and during the outpatient postpartum visit at 2 to 6 weeks after delivery. We calculated the percentage change at each time point from the preconception rate-pressure product (delta rate-pressure product). We used a mixed-linear model to analyze differences in the mean delta rate-pressure product over time and the influence of prepregnancy age, prepregnancy body mass index, and neuraxial anesthesia status during labor and delivery on these estimates. RESULTS: Our cohort comprised 316 patients. The mean rate-pressure product increased significantly from preconception starting at the third trimester of pregnancy and during labor and delivery (P≤.05). The mean delta rate-pressure product peaked at 12% and 38% in the third trimester and during labor and delivery, respectively. Prepregnancy body mass index was inversely correlated with the mean delta rate-pressure product changes (estimate, -0.308; 95% confidence interval, -0.536 to -0.80; P=.008). In contrast, neither the prepregnancy age, nor neuraxial anesthesia status during labor had a significant influence on this parameter. CONCLUSION: This study validates the transient but significant increase in the rate-pressure product, a clinical estimate of myocardial O2 demand, during uncomplicated pregnancies delivered vaginally at term. Pregnant individuals with lower prepregnancy body mass index experienced a sharper increase in this parameter. Patients who receive neuraxial anesthesia during labor and delivery experience similar changes in the rate-pressure product as those who did not.


Assuntos
Pressão Sanguínea , Frequência Cardíaca , Humanos , Feminino , Gravidez , Adulto , Estudos Retrospectivos , Pressão Sanguínea/fisiologia , Frequência Cardíaca/fisiologia , Período Pós-Parto/fisiologia , Trimestres da Gravidez/fisiologia , Consumo de Oxigênio/fisiologia , Trabalho de Parto/fisiologia , Parto Obstétrico/métodos , Parto Obstétrico/estatística & dados numéricos , Adulto Jovem , Estudos de Coortes
3.
J Am Heart Assoc ; 12(24): e031627, 2023 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-38108241

RESUMO

BACKGROUND: Both nighttime systolic blood pressure and pulse rate are associated with adverse outcomes in patients with chronic kidney disease (CKD). However, nighttime double product (DP), which is the product of nighttime systolic blood pressure and pulse rate, has not yet been investigated in this context. The present study aimed to explore the prognostic value of nighttime DP for adverse outcomes in patients with CKD and hypertension. METHODS AND RESULTS: This retrospective cohort study included a total of 1434 patients with nondialysis CKD complicated by hypertension. The patients were enrolled in Zhuhai and Guangzhou, China, with a median follow-up of 23.8 months. Patient enrollment for the high or low nighttime DP group was performed on the basis of the cutoff value determined by time-dependent receiver operator characteristic curve analysis. The primary end point was a composite of major cardiovascular and cerebrovascular events, and the secondary end point was all-cause death and composite renal end point. The 24-hour circadian DP rhythm was established via multiple-component cosinor analysis. Cox regression was used to explore the association between nighttime DP and adverse outcomes. The DP of nondialysis patients with CKD and hypertension showed a diurnal rhythm, which varied with renal function. After adjustment, high nighttime DP was associated with a higher risk for major cardiovascular and cerebrovascular events (hazard ratio [HR], 5.823 [95% CI, 2.382-14.233]), all-cause death (HR, 4.978 [95% CI, 2.205-11.240]), and composite renal event (HR, 1.661 [95% CI, 1.128-2.447]), compared with low nighttime DP. These associations were independent of nighttime systolic blood pressure and PR. CONCLUSIONS: The present cohort study demonstrated that DP had diurnal fluctuations and nighttime DP was an important prognostic factor in nondialysis patients with CKD and hypertension, outperforming traditional risk factors, including systolic blood pressure and pulse rate.


Assuntos
Hipertensão , Insuficiência Renal Crônica , Humanos , Estudos de Coortes , Prognóstico , Estudos Retrospectivos , Monitorização Ambulatorial da Pressão Arterial/métodos , Hipertensão/complicações , Hipertensão/diagnóstico , Hipertensão/epidemiologia , Insuficiência Renal Crônica/complicações , Insuficiência Renal Crônica/diagnóstico , Insuficiência Renal Crônica/epidemiologia , Pressão Sanguínea/fisiologia , Ritmo Circadiano/fisiologia
4.
Artigo em Inglês | MEDLINE | ID: mdl-37344400

RESUMO

BACKGROUND: The current study aimed to investigate the determinants of high double product (DP) by evaluating the association between resting DP, which is calculated as systolic blood pressure (SBP) multiplied by heart rate (HR), and blood test results and lifestyle factors. METHODS: This research included 973 participants in the baseline survey of the KOBE study, which included a cohort of urban residents. The possible DP determinants were identified by examining the association between lifestyle factors and laboratory findings and DP by analyzing covariance adjusted for sex and age. Logistic regression analysis was performed with high DP (SBP × HR ≥ 9145 mmHg beats/min or quintile according to sex) as outcome and DP determinants as independent variables. RESULTS: Age, hematocrit, and gamma-glutamyl transferase (log) level were positively associated with a high DP in both men and women. In addition, a high DP was positively associated with Homeostatic Model Assessment for Insulin Resistance score in women alone. Meanwhile, the amount of exercise was negatively associated with a high DP in men alone. CONCLUSIONS: High DP values at rest were associated with insulin resistance, gamma-glutamyl transferase, and the amount of exercise in participants without underlying disease.


Assuntos
Resistência à Insulina , Masculino , Humanos , Feminino , Estudos Transversais , Japão , População Urbana , Pressão Sanguínea/fisiologia , Frequência Cardíaca/fisiologia , Transferases
5.
Arch. cardiol. Méx ; 92(4): 446-453, Oct.-Dec. 2022. tab, graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1429678

RESUMO

Resumen Objetivo: El índice de eficiencia miocárdica (IEM) correlaciona el consumo miocárdico de oxígeno (MVO2) con el consumo máximo de oxígeno, el cual proporciona información sobre la eficiencia cardiovascular (EfCV). En deportistas, el IEM mejora posterior a un microciclo de entrenamiento, en el paciente con enfermedad cardiovascular sometido a un programa de rehabilitación cardiaca y prevención secundaria PRHCyPS, el comportamiento del IEM podría resultar un estimador relacionado con mejoría derivado de un periodo de entrenamiento. El objetivo del estudio fue determinar el comportamiento del IEM posterior a un PRCyPS en pacientes con cardiopatías y riesgo cardiovascular alto (RCVA). Métodos: Estudio de cohorte ambilectivo, descriptivo, analítico, no aleatorizado. Se seleccionaron pacientes con cardiopatías de etiología mixta con RCVA ingresados a un PRCyPS durante 4-6 semanas. A todos los pacientes se les realizó una prueba de ejercicio máximo en banda antes y después del PRCyPS. Se determinaron umbrales de consumo de oxígeno (VO2) pico, equivalentes metabólicos-carga, doble producto e IEM. Se estableció un punto de corte del IEM mediante una curva ROC con un valor de 7.37 con un área bajo la curva de 0.68 (IC 95%: 0.61-0.76; p < 0.001), sensibilidad 0.60 y 1-especificidad de 0.35. Resultados: Se incluyeron 193 pacientes con una media de edad de 62.3 años, en su mayoría del sexo masculino (66.2%). Se observaron porcentajes de cambio en el IEM -27.1% (p < 0.001), MET 43.1% (p < 0.001), doble producto 5.7% (p < 0.01) y MVO2: 8.3% (p < 0.01) al término del PRCyPS. Conclusiones: Se observó un cambio significativo en el IEM posterior a un PRCyPS, lo cual se asoció a una mejoría en la EfCV, sugiriendo que este pueda considerarse como un parámetro clínico que evaluar en los programas de rehabilitación cardiaca.


Abstract Objective: The myocardial efficiency index (MEI) correlates the Myocardial Oxygen Consumption (MVO2) with the Maximum Oxygen Consumption (VO2max), this index provides information about the cardiovascular efficiency (CVEf). In athletes, the MEI improves after a micro-cycle training, however in patients with cardiovascular disease undergoing Cardiac Rehabilitation Program (CRP), IEM behavior could be a good estimator related to the improvement training period. The objective of this study was to determine the myocardial efficiency index behavior in patients with heart disease and high cardiovascular risk (HCVR) after a CRP. Methods: Ambilective, descriptive, analytical, non-randomized cohort study was conducted. Patients with heart disease of mixed etiology and HCVR admitted to a CRP for 4-6 weeks were selected. All patients performed a maximal exercise test in band before and after the CPR. Thresholds of VO2 peak, METs-load, Double product (DP) and MEI were determined. A cut-off point for the MEI was established using a ROC curve with a value of 7.37, area under the curve: 0.68 (95% CI 0.61 - 0.76, p < 0.001), sensitivity 0.60 and 1-specificity 0.35. Results: 193 patients with a mean age of 62.3 years were included, predominantly men (66.2%). Percentages changes in the MEI-27.1% (p < 0.001),METs-43.1% (p < 0.001),DP 5.7% (p < 0.01), and MVO2: 8.3% (p < 0.01) were observed at the end of CRP. Conclusions: Significant change in the MEI were observed after CRP associated to CVEf improvement, suggesting that this parameter could be considered as a good clinical tool in the CRP care programs.

6.
Arch Cardiol Mex ; 92(4): 446-453, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36413696

RESUMO

OBJECTIVE: The myocardial efficiency index (MEI) correlates the Myocardial Oxygen Consumption (MVO2) with the Maximum Oxygen Consumption (VO2max), this index provides information about the cardiovascular efficiency (CVEf). In athletes, the MEI improves after a micro-cycle training, however in patients with cardiovascular disease undergoing Cardiac Rehabilitation Program (CRP), IEM behavior could be a good estimator related to the improvement training period. The objective of this study was to determine the myocardial efficiency index behavior in patients with heart disease and high cardiovascular risk (HCVR) after a CRP. METHODS: Ambilective, descriptive, analytical, non-randomized cohort study was conducted. Patients with heart disease of mixed etiology and HCVR admitted to a CRP for 4-6 weeks were selected. All patients performed a maximal exercise test in band before and after the CPR. Thresholds of VO2 peak, METs-load, Double product (DP) and MEI were determined. A cut-off point for the MEI was established using a ROC curve with a value of 7.37, area under the curve: 0.68 (95% CI 0.61 - 0.76, p < 0.001), sensitivity 0.60 and 1-specificity 0.35. RESULTS: 193 patients with a mean age of 62.3 years were included, predominantly men (66.2%). Percentages changes in the MEI-27.1% (p < 0.001),METs-43.1% (p < 0.001),DP 5.7% (p < 0.01), and MVO2: 8.3% (p < 0.01) were observed at the end of CRP. CONCLUSIONS: Significant change in the MEI were observed after CRP associated to CVEf improvement, suggesting that this parameter could be considered as a good clinical tool in the CRP care programs.


OBJETIVO: El índice de eficiencia miocárdica (IEM) correlaciona el consumo miocárdico de oxígeno (MVO2) con el consumo máximo de oxígeno, el cual proporciona información sobre la eficiencia cardiovascular (EfCV). En deportistas, el IEM mejora posterior a un microciclo de entrenamiento, en el paciente con enfermedad cardiovascular sometido a un programa de rehabilitación cardiaca y prevención secundaria PRHCyPS, el comportamiento del IEM podría resultar un estimador relacionado con mejoría derivado de un periodo de entrenamiento. El objetivo del estudio fue determinar el comportamiento del IEM posterior a un PRCyPS en pacientes con cardiopatías y riesgo cardiovascular alto (RCVA). MÉTODOS: Estudio de cohorte ambilectivo, descriptivo, analítico, no aleatorizado. Se seleccionaron pacientes con cardiopatías de etiología mixta con RCVA ingresados a un PRCyPS durante 4-6 semanas. A todos los pacientes se les realizó una prueba de ejercicio máximo en banda antes y después del PRCyPS. Se determinaron umbrales de consumo de oxígeno (VO2) pico, equivalentes metabólicos-carga, doble producto e IEM. Se estableció un punto de corte del IEM mediante una curva ROC con un valor de 7.37 con un área bajo la curva de 0.68 (IC 95%: 0.61-0.76; p < 0.001), sensibilidad 0.60 y 1-especificidad de 0.35. RESULTADOS: Se incluyeron 193 pacientes con una media de edad de 62.3 años, en su mayoría del sexo masculino (66.2%). Se observaron porcentajes de cambio en el IEM ­27.1% (p < 0.001), MET 43.1% (p < 0.001), doble producto 5.7% (p < 0.01) y MVO2: 8.3% (p < 0.01) al término del PRCyPS. CONCLUSIONES: Se observó un cambio significativo en el IEM posterior a un PRCyPS, lo cual se asoció a una mejoría en la EfCV, sugiriendo que este pueda considerarse como un parámetro clínico que evaluar en los programas de rehabilitación cardiaca.


Assuntos
Reabilitação Cardíaca , Cardiopatias , Masculino , Humanos , Pessoa de Meia-Idade , Feminino , Estudos de Coortes , Miocárdio , Teste de Esforço
7.
Lasers Med Sci ; 37(6): 2655-2665, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35235082

RESUMO

The aim of the present study was to analyze the effects of light-emitting diode therapy (LEDT) on cardiovascular effort during a single bout of high-intensity interval training (HIIT) and on blood pressure (BP), salivary nitrite, and heart rate variability (HRV) responses after the exercise session in postmenopausal women. Sixteen postmenopausal women between 50 and 70 years of age participated in the present study. The intervention comprised two sessions: placebo plus HIIT and LEDT plus HIIT, with a 14-day interval between sessions. The oxygen uptake (VO2), heart rate (HR), and rating of perceived exertion (RPE) were monitored throughout the HIIT sessions. Salivary samples were taken before, immediately post, and 30' and 60' post-HIIT sessions for nitric oxide (NO) analysis. In addition, HR and BP were checked before, 15 min, 30 min, 45 min, and 60 min post-HIIT sessions. HR data were used to calculate the HRV indices. Cardiovascular parameters during HIIT and BP, HRV, and NO responses were not different between placebo and LEDT conditions (p > 0.05). BP responses increased after compared to pre-exercise (p < 0.01). HRV was impaired post- compared to pre-exercise (p < 0.05). LEDT did not improve physiological performance during HIIT and did not accelerate the recovery of BP and autonomic modulation or change the NO release after exercise in postmenopausal women.


Assuntos
Treinamento Intervalado de Alta Intensidade , Feminino , Frequência Cardíaca/fisiologia , Humanos , Nitritos , Consumo de Oxigênio , Pós-Menopausa
8.
Res Q Exerc Sport ; 93(4): 749-757, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-34709130

RESUMO

Purpose: The aim of this study was to analyze the blood pressure (BP) and heart rate variability (HRV) responses in untrained postmenopausal women submitted to acute single sessions of high-intensity interval training (HIT). Method: Sixteen postmenopausal women (59.9 ± 5.6 years, 26.7 ± 3.0 kg/m2) participated in a random order of two acute sessions in a balanced crossover format: control without exercise in sitting position or HIT session. BP and heart rate (HR) were recorded before and during 60 min following the sessions. Results: Diastolic (DBP), mean BP (MBP), and double product (DPO) showed interaction (p < .01). DBP, MBP, and DPO increased (p < .01) after HIT but not after the control session. The area under the curve (AUC) of DBP (p = .02) and DPO (p < .01) were different between conditions. Time and frequency indices of HRV presented interaction (p < .05) which impaired these indices post-HIT, but not post-control. The AUC of time and frequency HRV indices were different between conditions. Conclusions: A single session of HIT may increase BP and cardiac stress and cause perturbation of the autonomic function in untrained postmenopausal women.


Assuntos
Treinamento Intervalado de Alta Intensidade , Feminino , Humanos , Pressão Sanguínea/fisiologia , Exercício Físico/fisiologia , Frequência Cardíaca/fisiologia , Pós-Menopausa , Estudos Cross-Over
9.
Open Respir Med J ; 16: e187430642201170, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-37273960

RESUMO

Background: Although asthmatics may present reduced exercise capacity, data on their cardiovascular responses during exercise testing have been scarcely investigated. The aim of this pilot case-control study is to test: a) whether double product (DP), an index of cardiovascular reserve, differs among patients with severe and mild-moderate asthma, and b) whether DP is associated with asthma control level, physical activity (PA) and exercise capacity, in asthmatics population. Materials and Methods: A group of patients with severe asthma (group S) and a matched group of patients with mild-moderate asthma (group M) was studied. All participants completed asthma control and physical activity (IPAC) questionnaires, lung function measurements and six-minute walk test. The exercise capacity (as 6-minute walk distance (6MWD) and corresponding work), the Borg Dyspnea, the rating of perceived excursion and the average PA METS were recorded. Results: A total of 18 patients were studied. DP at exercise end was significantly lower in group S, compared to group M (16412.2±4732.1 vs. 18594.8±3984.4 mmHgXbpm; p=0.041) and was moderately associated with % predicted 6MWD (r=0.592; p=0.001). Group S patients were also presented with lower moderate intensity PA, compared to group M, while exercise capacity was similar between the groups. Asthma control level had no impact on exercise capacity nor PA parameters. Conclusion: Patients with severe asthma may have impaired cardiovascular reserve as established by DP, even when exercise capacity is indifferent from patients with milder disease. As an easy-to-assess parameter, DP may offer further information in the functional evaluation of these patients.

10.
Clin Chim Acta ; 513: 50-56, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33307063

RESUMO

Serum chitotriosidase (CTO) activity was proposed as a biomarker in sarcoidosis being potentially useful in diagnostics. Nevertheless, a common duplication polymorphism (c.1049_1072dup24, Dup24) of the CTO gene influences CTO activity and thereby compromises its use in sarcoidosis. Here we aimed to substitute CTO activity with CTO concentration to prevent the confounding effect of Dup24. CTO activity, concentration and genetic backgrounds were determined in 80 histopathology proven sarcoidosis patients and 133 healthy individuals. CTO activities were lower in healthy individuals and sarcoidosis patients heterozygous for Dup24 mutation (472 ± 367 mU/L, n = 49; 2300 ± 2105 mU/L, n = 29) than in homozygous wild types (838 ± 856 mU/L, n = 81; 5125 ± 4802 mU/L, n = 48; p < 0.001, respectively). Sera of Dup24 homozygous individuals had no CTO activity. CTO concentrations were also lower in healthy individuals and sarcoidosis patients heterozygous for Dup24 mutation (7.2 ± 1.9 µg/L, n = 11; 63.16 ± 56.5 µg/L, n = 29) than in homozygous wild types (18.9 ± 13.0 µg/L, n = 36; 157.1 ± 132.4 µg/L, n = 47, p < 0.001, respectively) suggestive for an interaction between Dup24 mutation and CTO concentration determinations. We also identified a healthy Hungarian male subject without CTO activity carrying a rare mutation (c.(965_993)del), which mutation has been considered unique for Cypriot population to date. Taken together, CTO concentration determination does not add to the CTO activity measurement when CTO is used as a biomarker in sarcoidosis. Therefore, genotyping of CTO gene should be involved in the interpretation of laboratory findings.


Assuntos
Hexosaminidases , Sarcoidose , Hexosaminidases/genética , Humanos , Masculino , Mutação , Polimorfismo Genético , Sarcoidose/diagnóstico , Sarcoidose/genética
11.
J Clin Hypertens (Greenwich) ; 22(12): 2332-2342, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33035393

RESUMO

Systolic (SBP) and diastolic blood pressure (DBP) and mean arterial pressure (MAP) are risk factors for cardiovascular mortality (CVM). Pulse pressure (PP) is considered as an easily available marker of vascular stiffness and the double product (DP) as a marker of cardiac workload. Therefore, we have examined the predictive value of PP and DP in the Ludwigshafen Risk and Cardiovascular Health study, a monocentric cohort study of 3316 patients referred to coronary angiography. An increase of SBP or PP by 1mmHg increased the risk of CVM with hazard ratios of 1.009 (95% CI, 1.005-1.012) and 1.016 (1.012-1.020), respectively. Increasing DP by 100 mm Hg/min was associated with a 1.010 (1.007-1.013) higher risk of CVM. In patient subgroups with coronary artery disease (CAD) and heart failure (HF), PP and DP predicted CVM better than SBP or MAP. In a multivariate analysis adjusted for sex, BMI, diabetes, eGFR, hazard ratios for CVM for z-standardized PP, DP, SBP, and HR were 1.20, 1.16, 1.12, and 1.14. After adding age to the multivariate analysis, only DP and HR remained significant. We provide evidence that PP and DP are powerful predictors of CVM and all-cause mortality in a CV medium- to high-risk population, especially in patients with CAD and HF. While DP proved to be an independent predictor of cardiovascular and all-cause mortality also in multivariate analysis, PP was no independent predictor in our cohort with widespread antihypertensive treatment (>85%). PP is associated with age, presence of diabetes, obesity, and impaired renal function.


Assuntos
Pressão Sanguínea , Hipertensão , Anti-Hipertensivos/uso terapêutico , Estudos de Coortes , Humanos , Hipertensão/tratamento farmacológico , Fatores de Risco
12.
Int J Exerc Sci ; 13(6): 1156-1166, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32922648

RESUMO

The study aims at measuring the effects of six weeks of specific circuit training (SCT) according to the 15-15 modality, on selected physiological parameters in national top-level basketball players. It was an intervention study, undertaken with 44 senior players randomly assigned to two groups depending on the program: intervention (IG: n = 22; SCT) and control (CG: n = 22; usual content of the defending champion team's), submitted to a six-week training block. The heart rate recovery at 1 (HRR1) and then 2 (HRR2) minutes, the double product (DP) and V̇O2max were assessed prior to and at the end of the training period. As appropriate, the Student t-test on paired or independent samples, was used to compare measures and groups. At the end of the training period, the HRR1 decreased by 14.2% (p = 0.01) and 14.1% (p = 0.03) respectively in IG and CG. The mean HRR2 was higher in IG than in GC (63 ± 8 bpm versus 57 ± 6 bpm, p = 0.003) at the end of the training period. The variation of DP in IG was not significant (p = 0. 42) while it increased by 7.2% (p = 0.0005) in CG. The V̇O2max increased by 6.5% (p < 0. 001) in IG but not in CG (p = 0.50). The specific circuit training block in the 15-15 modality improved heart rate recovery at one minute and V̇O2max, but had no effect on the double product in the basketball players studied.

13.
Artigo em Inglês | MEDLINE | ID: mdl-32605106

RESUMO

Perceived lack of time is one of the most often cited barriers to exercise participation. High intensity interval training has become a popular training modality that incorporates intervals of maximal and low-intensity exercise with a time commitment usually shorter than 30 min. The purpose of this study was to examine the effects of short-term run interval training (RIT) on body composition (BC) and cardiorespiratory responses in undergraduate college students. Nineteen males (21.5 ± 1.6 years) were randomly assigned to a non-exercise control (CON, n = 10) or RIT (n = 9). Baseline measurements of systolic and diastolic blood pressure, resting heart rate (HRrest), double product (DP) and BC were obtained from both groups. VO2max and running speed associated with VO2peak (sVO2peak) were then measured. RIT consisted of three running treadmill sessions per week over 4 weeks (intervals at 100% sVO2peak, recovery periods at 40% sVO2peak). There were no differences in post-training BC or VO2max between groups (p > 0.05). HRrest (p = 0.006) and DP (p ≤ 0.001) were lower in the RIT group compared to CON at completion of the study. RIT lowered HRrest and DP in the absence of appreciable BC and VO2max changes. Thereby, RIT could be an alternative model of training to diminish health-related risk factors in undergraduate college students.


Assuntos
Hemodinâmica/fisiologia , Treinamento Intervalado de Alta Intensidade , Corrida , Humanos , Masculino , Consumo de Oxigênio , Estudantes
14.
Heart Lung Circ ; 29(10): 1511-1516, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32224086

RESUMO

BACKGROUND: Autonomic nerve system and endothelial function play important roles in vasospastic angina. Elevated heart rate (HR), blood pressure (BP), and double product (DP) can increase endothelial-dependent coronary artery dilation and blood flow. However, the impact of HR, BP, and DP on occurrence and severity of VSA in the clinical setting is unclear. METHOD: A total of 170 patients undergoing intracoronary acetylcholine (ACh) provocation test during hospitalisation was included. Resting HR, BP, and DP were measured at least four times, and their variabilities were evaluated by standard deviations (SD) and coefficient of variations (CVs). Angiographic coronary artery vasospasm was defined as total or subtotal occlusion induced by ACh provocation. RESULTS: Mean±SD HR (65.7±9.1 vs 69.6±7.9 beats per minute; p=0.003), systolic BP (122.3±13.4 vs 127.7±14.6 mmHg; p=0.01), and DP (8,001±1,229 vs 8,903±1,495; p<0.001) were significantly lower in patients with a positive ACh test than the counterpart, whereas SD and CV of both HR and systolic BP were not significantly different between the two groups. Mean HR, BP, and DP progressively decreased with increase in the number of vessels with angiographic vasospasm. Multivariate analysis showed current smoking and lower DP as independent predictors of the greater number of vessels with provoked angiographic vasospasm. CONCLUSIONS: Resting HR, BP, and DP were lower in patients with vasospastic angina, especially in those with severe vasospasm.


Assuntos
Acetilcolina/administração & dosagem , Sistema Nervoso Autônomo/fisiopatologia , Pressão Sanguínea/fisiologia , Vasoespasmo Coronário/diagnóstico , Frequência Cardíaca/fisiologia , Descanso/fisiologia , Vasoconstrição/efeitos dos fármacos , Idoso , Angiografia Coronária , Vasoespasmo Coronário/fisiopatologia , Feminino , Seguimentos , Humanos , Injeções Intra-Arteriais , Masculino , Estudos Retrospectivos , Índice de Gravidade de Doença , Vasodilatadores/administração & dosagem
15.
J Am Coll Nutr ; 39(5): 414-421, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-31526307

RESUMO

Objective: This study investigated the effect of a single administration of dark or milk chocolate on blood pressure (BP), heart rate (HR), and double product (DP) in young healthy women at rest and during acute mental stress.Method: Measurements consisted of anthropometry, BP, and HR. Mean arterial BP (MAP) and DP were computed. The relative reactivity of individual variables was quantified as to their percentage change during the rest or test of mental arithmetic (MA) with respect to the respective baseline value. All subjects underwent two tests of MA-one before chocolate administration and the second one 2 hours after chocolate (1 mg/g of body weight) ingestion.Results: Two hours after ingestion at rest, dark chocolate administration resulted in a significant increase in relative values of systolic BP and DP by 5.1% ± 1.4% and 13.7% ± 3.2%, respectively, compared to the responses in the milk chocolate group (-2.4% ± 1.6% and 0.6% ± 3.4%, respectively, p < 0.04 for both comparisons) without changes in diastolic BP, HR, and MAP. During MA-induced acute stress, the relative magnitude of the reactivity of diastolic BP, HR, MAP, and DP decreased by about 10, 16, 8, and 23 percentage points, respectively, 2 hours after ingestion of dark chocolate compared to the relative reactivity determined before dark chocolate ingestion. Milk chocolate failed to affect any of the above-mentioned parameters at rest or during stress.Conclusions: The single oral intake of 85% dark chocolate increased relative values of systolic BP and DP at rest but buffered the reactivity of diastolic BP, HR, MAP, and DP during mental stress, which was not found after ingestion of milk chocolate. Thus, dark chocolate might have a beneficial effect during acute stress due to its ability to buffer cardiovascular reactivity in young healthy women.


Assuntos
Sistema Cardiovascular/efeitos dos fármacos , Catequina/farmacocinética , Chocolate , Ingestão de Alimentos/fisiologia , Estresse Psicológico/dietoterapia , Doença Aguda , Adulto , Pressão Sanguínea/efeitos dos fármacos , Cognição/efeitos dos fármacos , Feminino , Frequência Cardíaca/efeitos dos fármacos , Humanos , Descanso/fisiologia , Estresse Psicológico/fisiopatologia , Adulto Jovem
16.
Stress ; 23(3): 248-255, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31466500

RESUMO

The relationship between subjective stress perception and the objective stress response to acute stress stimuli is not sufficiently understood. The aim of the present study was to test the hypothesis that the neuroendocrine response in socially evaluated cold pressor test (CPT) depends on the extent of perceived stressfulness of the stimulus. The test was performed in 24 healthy male volunteers. Subjective stress perception was assessed using nine visual analog scales. The subjects were divided to low and high stress perception groups according to the median split of the scores. Subjects with high stress perception exhibited slightly lower values of systolic blood pressure and lower overall concentrations of salivary cortisol compared to subjects with low stress perception. Salivary alpha-amylase activity did not show significant changes. Salivary aldosterone decreased in time in subjects with low but increased early after the test in subjects with high stress perception. Interestingly, salivary concentrations of the pro-inflammatory cytokine interleukin-1beta were considerably higher in subjects with high stress perception, particularly immediately before the test. The differences in salivary cortisol and interleukin-1beta were confirmed by the analysis with distress as a continuous covariate. Distress scores correlated negatively with salivary cortisol and positively with interleukin-1beta. The rate pressure product, which is a global measure of energy consumption by the heart, was significantly higher immediately before than after the stress exposure. The present findings show that concentrations of interleukin-1beta are a sensitive component of the stress response at the time before the stressful event.Lay summaryIt is generally expected that higher perceived stressfulness of a stimulus is accompanied by higher activation of stress-related systems. This study evaluating a combined psychosocial and physical stress situation in healthy men provides evidence that individual parameters of the stress response are differently related to perceived stress intensity. Subjects with high stress perception exhibited lower systolic blood pressure and salivary cortisol, higher interleukin-1beta, marginal differences in alpha amylase and aldosterone compared to subjects with low stress perception, which might be important for stress coping.


Assuntos
Hidrocortisona , alfa-Amilases Salivares , Humanos , Interleucina-1beta , Masculino , Saliva , Estresse Psicológico
17.
Clin Chim Acta ; 500: 155-162, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31672631

RESUMO

Establishing the diagnosis of sarcoidosis most often requires biopsy and histopathologic evaluation, since there is no single marker with sufficient specificity and sensitivity for the disease. Our aims were to determine and compare the diagnostic accuracies of several potential biomarkers and to develop a combined biomarker analysis tool for the diagnosis of sarcoidosis. 133 healthy individuals and 104 patients with suspected sarcoidosis and diagnostic thoracic surgery were enrolled into this study. Histopathologic results were contrasted to biomarker levels of chitotriosidase (CTO), serum amyloid-A (SAA), soluble interleukin-2 receptor (sIL-2R), lysozyme (LZM) or angiotensin converting enzyme (ACE). Sarcoidosis was confirmed by histopathology in 69 patients. CTO activity, sIL-2R concentration and ACE activity could discriminate between sarcoidosis and control patients, while SAA and LZM concentrations could not. A new combined parameter, which was derived from the multiplication of ACE by CTO activities (double product) showed the best diagnostic accuracy in this clinical study: (AUC = 0.898, sensitivity: 90.5%, specificity: 79.3%, positive and negative predictive values: 90.5% and 79.3%, respectively). Sarcoidosis can be diagnosed with the combined analysis of ACE and CTO activities more accurately than with single serum biomarkers in the absence of invasive biopsy in the majority of cases with pulmonary manifestation of sarcoidosis.


Assuntos
Análise Química do Sangue , Hexosaminidases/sangue , Peptidil Dipeptidase A/sangue , Sarcoidose/sangue , Sarcoidose/diagnóstico , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
18.
Breast Cancer ; 26(6): 729-737, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31087274

RESUMO

BACKGROUND: Breast cancer treatment may increase non-cancer related mortality risk due to unintended cardiovascular consequences. The aim of this study was to investigate the strongest correlate of cardiovascular health (CVH) in female breast cancer survivors, cardiorespiratory fitness or fatness. METHODS: Fifty-one women (59 ± 9 years, BMI 26.4 ± 4.8 kg/m2) previously diagnosed and treated for primary breast cancer were assessed using pulse wave analysis to determine central arterial wave reflection (augmentation index, AIx) and central systolic blood pressure (cSBP). A composite Z score calculated which incorporated central double product and AIx, as an indicator of CVH. Dual energy X-ray absorptiometry was used to obtain total body fat percentage (BF%). Cardiorespiratory fitness was determined using the single-stage walk test to predict maximal oxygen uptake ([Formula: see text]). RESULTS: Linear regression analysis revealed that fitness was associated with AIx after adjusting for BF %, age and time post-treatment completion (ß = - 0.271, p = 0.010). A significant association between BF% and AIx after adjusting for fitness and age was found (ß = 0.166, p = 0.0005); however, this association was lost when time post-treatment was included in the model (ß = 0.166, p = 0.167). Both fitness (ß = - 0.347, p = 0.0005) and BF% (ß = 0.333, p = 0.013) were independently associated with CVH in the fully adjusted model. CONCLUSIONS: This study provides evidence for an association between cardiorespiratory fitness and cardiovascular health in female breast cancer survivors. While fatness may be associated with cardiovascular health, it appears to be more strongly associated with age.


Assuntos
Composição Corporal/fisiologia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/mortalidade , Sobreviventes de Câncer , Aptidão Cardiorrespiratória/fisiologia , Adulto , Fatores Etários , Idoso , Pressão Sanguínea , Índice de Massa Corporal , Doenças Cardiovasculares/etiologia , Quimiorradioterapia/efeitos adversos , Feminino , Frequência Cardíaca , Humanos , Modelos Lineares , Pessoa de Meia-Idade , Prognóstico , Taxa de Sobrevida
19.
Rev. bras. ciênc. mov ; 27(2): 48-54, abr.-jun.2019. ilus
Artigo em Português | LILACS | ID: biblio-1008615

RESUMO

: O treino com oclusão vascular (OV) tem sido amplamente utilizado devido a seus benefícios. No entanto, ainda permanecem escassos os estudos em relação às respostas cardiovasculares a este tipo de treino. O objetivo deste estudo foi verificar as respostas hemodinâmicas e trabalho do miocárdio com diferentes níveis de oclusão vascular no exercício de extensão unilateral de joelho. Recrutamos 14 voluntários e estes foram submetidos a um protocolo de três séries de 15 repetições com 30% de uma repetição máxima no exercício de extensão unilateral de joelho com diferentes níveis de OV, sendo eles: sem oclusão (SO), oclusão parcial (OP) e oclusão total (OT). A pressão arterial sistólica (PAS) e frequência cardíaca (FC) foram verificadas em repouso e ao final de cada série do protocolo. A análise de variância de duas entradas com post hoc de Bonferroni foi utilizado para verificar diferença entre os tipos de oclusão, tendo nível de significância quando p<0.05. Observou-se diferença da PAS, FC e duploproduto (DP) entre as séries e o repouso (p<0,001). Independentemente do tipo de execução, a PAS, FC e DP foram maiores na 2ª e 3ª séries comparadas à 1ª. A OP e OT proporcionaram maiores valores de PAS na 3ª série comparada à 2ª série (p= 0,036; p=0,025). Por fim, houve diferença na 3ª série entre a OT e SO (p= 0,01). O presente estudo conclui que a sobrecarga cardiovascular tem relação direta com o volume de exercício e o nível de oclusão....(AU)


Vascular occlusion (VO) training has been widely used because of its benefits. However, there are still few studies regarding cardiovascular responses to this type of training. The objective of this study was to verify hemodynamics responses and myocardial workload with different occlusion levels on unilateral knee extension exercise. We recruited 14 volunteers and were submitted to a protocol of three series of 15 repetitions with 30% of a maximal repetition in the exercise of with different levels of OV, being: no occlusion (NO), partial occlusion (PO) and total occlusion (TO). Systolic blood pressure (SBP) and heart rate (HR) were checked at rest and at the end of each protocol series. Bonferroni post hoc twoway analysis of variance was used to verify the difference between occlusion types, with significance level when p <0.05. A difference of SBP, HR and double-product (DP) between series and rest was observed (p<0.001). Regardless of the type of execution, SBP, HR and DP were higher in the 2nd and 3rd grades compared to the 1st. The PO and TO provided higher SBP values in the 3rd grade compared to the 2nd grade (p = 0.036, p = 0.025). Finally, there was a difference in the 3rd grade between TO and NO (p =0.01). It's concluded that the cardiovascular overload has direct relation with exercise volume and occlusion level....(AU)


Assuntos
Humanos , Masculino , Feminino , Pressão Arterial , Frequência Cardíaca , Educação Física e Treinamento , Exercício Físico
20.
Cardiol J ; 26(1): 20-28, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-29131282

RESUMO

BACKGROUND: Chronic heart failure (CHF) is an important epidemiological and therapeuthic issue with poor prognosis. The aim of the study was to estimate the prognostic value of daytime heart rate (HR), blood pressure (BP), their products and quotients in patients with CHF. METHODS: The study included 80 stable patients with CHF and reduced left ventricular ejection frac- tion (LVEF ≤ 35%). Physical examination, laboratory blood tests, electrocardiogram, chest X-ray, echocardiography, 6-minute walk test, telemetry monitoring and BP measurements were performed in all participants. We estimated mean daytime: BP, HR, their products and quotients. The follow-up period was 6 months. Major adverse cardiac events (MACE) included: death, cardiovascular death, hospitalization due to CHF exacerbation. RESULTS: The analysis involved all recruited patients with CHF (91% men) aged 59 ± 12 years, in New York Heart Association class 2.15 ± 0.57 and reduced LVEF (mean LVEF: 23 ± 6%). The 3-month and 6-month mortality rates were 4% and 6%, respectively. There was a significant correlation between diastolic blood pressure (DBP), all-cause mortality (p = 0.048) and CHF decompensation (p = 0.0004) after 3-month observation period. No relationship was found between HR or systolic blood pressure (SBP) and MACE. Both higher SBP × HR and DBP × HR products were related to lower risk of heart failure exacerbations during 6-month follow-up. None of the analyzed products or ratios had an impact on mortality in this study group. CONCLUSIONS: Diastolic blood pressure, SBP × HR and DBP × HR products may be useful in sub- sequent heart failure exacerbation risk stratification. Moreover, DBP value may predict short-term mortality in patients with CHF.


Assuntos
Pressão Sanguínea/fisiologia , Ritmo Circadiano/fisiologia , Insuficiência Cardíaca/fisiopatologia , Frequência Cardíaca/fisiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Causas de Morte/tendências , Teste de Esforço , Feminino , Seguimentos , Insuficiência Cardíaca/epidemiologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Polônia/epidemiologia , Prognóstico , Estudos Prospectivos , Fatores de Risco , Volume Sistólico/fisiologia , Taxa de Sobrevida/tendências , Adulto Jovem
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