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1.
Int J Mol Sci ; 24(18)2023 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-37762512

RESUMO

The renal system is engaged in metabolic syndrome (MS) and metabolites of arachidonic acid (AA) participate in renal homeostasis and disruption of functionality. Hibiscus sabdariffa L (HSL) is used as a diuretic and could improve renal function. The aim of this study was to assess if treatment with HSL at 2% improves renal function in MS through the metabolites of AA. A total of 24 male Wistar rats were divided into four groups: Group 1, control (C); Group 2, MS with 30% sucrose in drinking water, Group 3, MS plus HSL infusion at 2% (MS+HSL); and Group 4, C+HSL. We evaluated the perfusion pressure changes (∆-PP), the activities of cyclooxygenases (COXs), the percentage of AA, the expressions of PLA2, COX2, COX1, 5-LOX, TAXS and CYP450, and the concentrations of prostaglandins in the kidney from rats with MS. There was a decrease in the ∆-PP, in the activities of COXs, and the expressions of COX2 and CYP450 (p ≤ 0.03, respectively)as well asPGE2, TxB2, and LKB4 (p ≤ 0.01, respectively). However, the percentage of AA and expressions of PLA2 and PGE1 (p = 0.01, respectively) were increased in C and MS+HSL. The HSL treatment improved the function and anatomical structure of the kidneys in the MS rats, through antioxidant molecules, and inhibited the pathways that metabolize the AA including that of PLA2, COX2, 5-LOX, TAXS, and CYP450 while favoring the COX1 pathway. This improves the vascular resistance of renal arterioles.


Assuntos
Hibiscus , Síndrome Metabólica , Masculino , Ratos , Animais , Ácido Araquidônico , Ratos Wistar , Ciclo-Oxigenase 2 , Síndrome Metabólica/tratamento farmacológico , Rim/fisiologia , Fosfolipases A2
2.
Int J Mol Sci ; 23(20)2022 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-36293383

RESUMO

Deodorized garlic (DG) may favor the activity of the antioxidant enzymes and promote the synthesis of hydrogen sulfide (H2S). The objective was to test if DG favors an increase in H2S and if it decreases the oxidative stress caused by lipopolysaccharide (LPS) in rat hearts. A total of 24 rats were divided into 4 groups: Group 1 control (C), Group 2 LPS, Group 3 DG, and Group 4 LPS plus DG. The cardiac mechanical performance (CMP), coronary vascular resistance (CVR), and oxidative stress markers, such as total antioxidant capacity (TAC), glutathione (GSH), selenium (Se), lipid peroxidation (LPO), thiols, hydrogen sulfide (H2S), and the activities and expressions of thioredoxin reductase (TrxR), glutathione peroxidase (GPx), and glutathione-S-transferase (GST), cystathionine synthetase (CBS), cystathionine γ-lyase (CTH), iNOS, and eNOS-p, were analyzed in the heart. Infarct zones in the cardiac tissue were present (p = 0.01). The CMP and CVR decreased and increased (p ≤ 0.05), TAC, GSH, H2S, NO, thiols, and GST activity (p ≤ 0.01) decreased, and LPO and iNOS increased (p ≤ 0.05). The activities and expressions of TrxR, GPx, eNOS-p, CTH, and CBS (p ≤ 0.05) decreased with the LPS treatment; however, DG normalized this effect. DG treatment decreases heart damage caused by LPS through the cross-talk between the H2S and NO systems.


Assuntos
Alho , Sulfeto de Hidrogênio , Selênio , Animais , Ratos , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Cistationina beta-Sintase/metabolismo , Cistationina gama-Liase/metabolismo , Alho/metabolismo , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Sulfeto de Hidrogênio/farmacologia , Sulfeto de Hidrogênio/metabolismo , Lipopolissacarídeos/farmacologia , Estresse Oxidativo , Selênio/farmacologia , Compostos de Sulfidrila/farmacologia , Tiorredoxina Dissulfeto Redutase/metabolismo , Transferases/metabolismo
3.
Life (Basel) ; 12(7)2022 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-35888108

RESUMO

Cardiovascular regulatory mechanisms that fail to compensate for ultrafiltration and cause hypovolemia during hemodialysis (HD) are not completely understood. This includes the interaction between the autonomic nervous system and the biochemistry that regulates blood pressure and modulates cardiac activity and vascular tone in response to hypovolemia in patients treated with HD. The objective was to evaluate the association of spectral indices of heart rate variability (HRV) with serum levels of angiotensin II, angiotensin 1-7, nitric oxide and total antioxidant capacity during HD. Electrocardiographic records were obtained from 20 patients during HD (3 h), from which HRV data and spectral power data in the very-low-frequency (VLF), low-frequency (LF) and high-frequency (HF) bands were generated. Three blood samples per patient were collected during HD (0.0, 1.5, 3.0 h) to determine the levels of biomarkers involved in the pressor response during HD. Angiotensin II had a positive correlation with VLF (r = 0.390) and with LF/HF (r = 0.359) and a negative correlation with LF (r = -0.262) and HF (r = -0.383). There were no significant correlations between HRV and the other biomarkers. These results suggest that during HD, VLF could reflect the serum levels of angiotensin II, which may be associated with the autonomic response to HD.

4.
Molecules ; 27(3)2022 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-35164296

RESUMO

The transient vanilloid receptor potential type 1 (TRPV1) regulates neuronal and vascular functions mediated by nitric oxide (NO) and by the calcitonin gene-related peptide (CGRP). Here, we study the participation of TRPV1 in the regulation of myocardial injury caused by ischemia-reperfusion and in the control of NO, tetrahydrobiopterin (BH4), the cGMP pathway, CGRP, total antioxidant capacity (TAC), malondialdehyde (MDA) and phosphodiesterase-3 (PDE-3). Isolated hearts of Wistar rats perfused according to the Langendorff technique were used to study the effects of an agonist of TRPV1, capsaicin (CS), an antagonist, capsazepine (CZ), and their combination CZ+CS. The hearts were subjected to three conditions: (1) control, (2) ischemia and (3) ischemia-reperfusion. We determined cardiac mechanical activity and the levels of NO, cGMP, BH4, CGRP, TAC, MDA and PDE-3 in ventricular tissue after administration of CS, CZ and CZ+CS. Western blots were used to study the expressions of eNOS, iNOS and phosphorylated NOS (pNOS). Structural changes were determined by histological evaluation. CS prevented damage caused by ischemia-reperfusion by improving cardiac mechanical activity and elevating the levels of NO, cGMP, BH4, TAC and CGRP. TRPV1 and iNOS expression were increased under ischemic conditions, while eNOS and pNOS were not modified. We conclude that the activation of TRPV1 constitutes a therapeutic possibility to counteract the damage caused by ischemia and reperfusion by regulating the NO pathway through CGRP.


Assuntos
Coração/fisiopatologia , Traumatismo por Reperfusão Miocárdica/fisiopatologia , Óxido Nítrico/metabolismo , Estresse Oxidativo , Canais de Cátion TRPV/metabolismo , Animais , Masculino , Traumatismo por Reperfusão Miocárdica/metabolismo , Ratos , Ratos Wistar , Transdução de Sinais
5.
Blood Purif ; 50(2): 180-187, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33454709

RESUMO

INTRODUCTION: Patients in hemodiafiltration (HDF) eliminate volume overload by ultrafiltration. Vascular volume loss is among the main mechanisms contributing to adverse events such as intradialytic hypotension. Here, we hypothesize that the intradialytic exercise (IDEX) is an intervention that could improve the acute response of physiological mechanisms involved during vascular volume loss. To test this hypothesis, we evaluated the hemodynamic response to mild aerobic exercise during HDF. METHODS: Nineteen end-stage renal disease (ESRD) patients (11 women: 40 ± 10.8 years old, and 8 men: 42 ± 21 years old) receiving HDF thrice a week, with 6 months of previous physical conditioning, participated in this study. Three HDF sessions were scheduled for each patient: 1 resting in supine position, 1 resting in sitting position, and 1 doing aerobic exercise. The first 2 sessions were taken as control. The ultrafiltration rate was set to 800 mL/h in each session. The hemodynamic response was monitored through the relative blood volume (RBV), and cardiovascular variables measured noninvasively by photoplethysmography. Adequacy variables such as Kt/V and percentage reduction of urate, urea, creatinine (Cr), and phosphate were also monitored. FINDINGS: The decrease rate of the RBV was smaller in the session with IDEX compared to the sessions with no exercise. No differences were found neither in the cardiovascular variables nor in the adequacy variables among the 3 sessions. There were no hypotension events during the session with exercise, and 8 events during the sessions without exercise (p = 0.002). DISCUSSION: Mild exercise during HDF decreased the RBV drop and was associated with less hypotension events. The lack of differences in the hemodynamic variables suggests an adequate acute response of cardiovascular compensation variables to intradialytic hypovolemia.


Assuntos
Volume Sanguíneo , Exercício Físico , Hemodiafiltração , Falência Renal Crônica/terapia , Adulto , Feminino , Hemodiafiltração/efeitos adversos , Hemodiafiltração/métodos , Hemodinâmica , Humanos , Hipotensão/etiologia , Falência Renal Crônica/sangue , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Adulto Jovem
6.
Artigo em Inglês | MEDLINE | ID: mdl-31557799

RESUMO

The purpose of the present study was to analyze the actions of transient receptor potential vanilloid type 1 (TRPV1) agonist capsaicin (CS) and of its antagonist capsazepine (CZ), on cardiac function as well as endothelial biomarkers and some parameters related with nitric oxide (NO) release in L-NG-nitroarginine methyl ester (L-NAME)-induced hypertensive rats. NO has been implicated in the pathophysiology of systemic arterial hypertension (SAHT). We analyzed the levels of nitric oxide (NO), tetrahydrobiopterin (BH4), malondialdehyde (MDA), total antioxidant capacity (TAC), cyclic guanosin monophosphate (cGMP), phosphodiesterase-3 (PDE-3), and the expression of endothelial nitric oxide synthase (eNOS), guanosine triphosphate cyclohydrolase 1 (GTPCH-1), protein kinase B (AKT), and TRPV1 in serum and cardiac tissue of normotensive (118±3 mmHg) and hypertensive (H) rats (165 ± 4 mmHg). Cardiac mechanical performance (CMP) was calculated and NO was quantified in the coronary effluent in the Langendorff isolated heart model. In hypertensive rats capsaicin increased the levels of NO, BH4, cGMP, and TAC, and reduced PDE-3 and MDA. Expressions of eNOS, GTPCH-1, and TRPV1 were increased, while AKT was decreased. Capsazepine diminished these effects. In the hypertensive heart, CMP improved with the CS treatment. In conclusion, the activation of TRPV1 in H rats may be an alternative mechanism for the improvement of cardiac function and systemic levels of biomarkers related to the bioavailability of NO.


Assuntos
Coração/efeitos dos fármacos , Hipertensão/metabolismo , Miocárdio/metabolismo , Óxido Nítrico/metabolismo , Canais de Cátion TRPV/metabolismo , Animais , Biomarcadores/sangue , /metabolismo , Pressão Sanguínea , Capsaicina/análogos & derivados , Capsaicina/farmacologia , Capsaicina/uso terapêutico , Avaliação Pré-Clínica de Medicamentos , Hipertensão/tratamento farmacológico , Masculino , NG-Nitroarginina Metil Éster , Óxido Nítrico Sintase Tipo III , Estresse Oxidativo , Proteínas Proto-Oncogênicas c-akt , Ratos , Ratos Wistar , Canais de Cátion TRPV/agonistas , Canais de Cátion TRPV/antagonistas & inibidores , Resistência Vascular
7.
Arch. cardiol. Méx ; 87(1): 61-71, ene.-mar. 2017. tab, graf
Artigo em Espanhol | LILACS | ID: biblio-887494

RESUMO

Resumen: Objetivo: Mejorar la identificación de cimas y pies en el pulso fotopletismográfico (PPG, por sus siglas en inglés), deformado por efecto del ruido miocinético, mediante la implementación de un dedal modificado y filtrado adaptativo. Método: Se obtuvo el PPG en 10 voluntarios sanos empleando 2 sistemas de fotopletismografía colocados en el dedo índice de cada mano, y registrándolos simultáneamente durante 3 min. Durante el primer minuto de registro, ambas manos estuvieron en reposo, y durante los 2 min posteriores, solo la mano izquierda realizó movimientos cuasi-periódicos para añadir ruido miocinético. Se emplearon 2 metodologías para procesar las señales fuera de línea, en una se usó un filtro con el algoritmo de mínimos cuadrados promediados (LMS, por sus siglas en inglés) y en la otra se hizo un preprocesamiento adicional al filtrado LMS. Ambas metodologías fueron comparadas y la de menor error porcentual en la señal recuperada se utilizó para valorar la mejora en la identificación de cimas y pies del PPG. Resultados: El error promedio obtenido fue del 22.94% para la primera metodología, y del 3.72% para la segunda. Los errores en la identificación de cimas y pies antes de filtrar el PPG fueron del 24.26 y 48.39%, respectivamente, una vez filtrados, disminuyeron a 2.02 y 3.77%, respectivamente. Conclusiones: El filtrado adaptativo basado en el algoritmo LMS, más una etapa de preprocesamiento, permite atenuar el ruido miocinético en el PPG, y aumentar la efectividad en la identificación de cimas y pies de pulso, que resultan de gran importancia para una valoración médica.


Abstract: Objective: To improve the identification of peaks and feet in photoplethysmographic (PPG) pulses deformed by myokinetic noise, through the implementation of a modified fingertip and applying adaptive filtering. Method: PPG signals were recordedfrom 10 healthy volunteers using two photoplethysmography systems placed on the index finger of each hand. Recordings lasted three minutes andwere done as follows: during the first minute, both handswere at rest, and for the lasting two minutes only the left hand was allowed to make quasi-periodicmovementsin order to add myokinetic noise. Two methodologies were employed to process the signals off-line. One consisted on using an adaptive filter based onthe Least Mean Square (LMS) algorithm, and the other includeda preprocessing stage in addition to the same LMS filter. Both filtering methods were compared and the one with the lowest error was chosen to assess the improvement in the identification of peaks and feet from PPG pulses. Results: Average percentage errorsobtained wereof 22.94% with the first filtering methodology, and 3.72% withthe second one. On identifying peaks and feet from PPG pulsesbefore filtering, error percentages obtained were of 24.26% and 48.39%, respectively, and once filtered error percentageslowered to 2.02% for peaks and 3.77% for feet. Conclusions: The attenuation of myokinetic noise in PPG pulses through LMS filtering, plusa preprocessing stage, allows increasingthe effectiveness onthe identification of peaks and feet from PPG pulses, which are of great importance for medical assessment.


Assuntos
Humanos , Fotopletismografia/métodos , Modelos Lineares , Artefatos
8.
Arch Cardiol Mex ; 87(1): 61-71, 2017.
Artigo em Espanhol | MEDLINE | ID: mdl-27956339

RESUMO

OBJECTIVE: To improve the identification of peaks and feet in photoplethysmographic (PPG) pulses deformed by myokinetic noise, through the implementation of a modified fingertip and applying adaptive filtering. METHOD: PPG signals were recordedfrom 10 healthy volunteers using two photoplethysmography systems placed on the index finger of each hand. Recordings lasted three minutes andwere done as follows: during the first minute, both handswere at rest, and for the lasting two minutes only the left hand was allowed to make quasi-periodicmovementsin order to add myokinetic noise. Two methodologies were employed to process the signals off-line. One consisted on using an adaptive filter based onthe Least Mean Square (LMS) algorithm, and the other includeda preprocessing stage in addition to the same LMS filter. Both filtering methods were compared and the one with the lowest error was chosen to assess the improvement in the identification of peaks and feet from PPG pulses. RESULTS: Average percentage errorsobtained wereof 22.94% with the first filtering methodology, and 3.72% withthe second one. On identifying peaks and feet from PPG pulsesbefore filtering, error percentages obtained were of 24.26% and 48.39%, respectively, and once filtered error percentageslowered to 2.02% for peaks and 3.77% for feet. CONCLUSIONS: The attenuation of myokinetic noise in PPG pulses through LMS filtering, plusa preprocessing stage, allows increasingthe effectiveness onthe identification of peaks and feet from PPG pulses, which are of great importance for medical assessment.


Assuntos
Fotopletismografia/métodos , Artefatos , Humanos , Modelos Lineares
9.
J Endocrinol ; 232(2): 221-235, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27872198

RESUMO

Oophorectomy in adult rats affected cardiac mitochondrial function. Progression of mitochondrial alterations was assessed at one, two and three months after surgery: at one month, very slight changes were observed, which increased at two and three months. Gradual effects included decrease in the rates of oxygen consumption and in respiratory uncoupling in the presence of complex I substrates, as well as compromised Ca2+ buffering ability. Malondialdehyde concentration increased, whereas the ROS-detoxifying enzyme Mn2+ superoxide dismutase (MnSOD) and aconitase lost activity. In the mitochondrial respiratory chain, the concentration and activity of complex I and complex IV decreased. Among other mitochondrial enzymes and transporters, adenine nucleotide carrier and glutaminase decreased. 2-Oxoglutarate dehydrogenase and pyruvate dehydrogenase also decreased. Data strongly suggest that in the female rat heart, estrogen depletion leads to progressive, severe mitochondrial dysfunction.


Assuntos
Mitocôndrias Cardíacas/metabolismo , Ovariectomia , Fosforilação Oxidativa , Consumo de Oxigênio/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Aconitato Hidratase/metabolismo , Animais , Feminino , Malondialdeído/metabolismo , Ratos , Superóxido Dismutase/metabolismo
10.
Molecules ; 21(11)2016 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-27792195

RESUMO

The antioxidant properties of aged garlic extract (AGE) on cardiovascular functioning (CF) in metabolic syndrome (MS) remains poorly studied. Here we study the AGE effects on CF in a rat model of MS. Control rats plus saline solution (C + SS), MS rats (30% sucrose in drinking water from weaning) plus saline solution (MS + SS), control rats receiving AGE (C + AGE 125 mg/Kg/12 h) and MS rats with AGE (MS + AGE) were studied. MS + SS had increased triglycerides, systolic blood pressure, insulin, leptin, HOMA index, and advanced glycation end products. AGE returned their levels to control values (p < 0.01). Cholesterol was decreased by AGE (p = 0.05). Glutathion and GPx activity were reduced in MS + SS rats and increased with AGE (p = 0.05). Lipid peroxidation was increased in MS + SS and AGE reduced it (p = 0.001). Vascular functioning was deteriorated by MS (increased vasocontraction and reduced vasodilation) and AGE improved it (p = 0.001). Coronary vascular resistance was increased in MS rats and AGE decreased it (p = 0.001). Cardiac performance was not modified by MS but AGE increased it. NO measured in the perfusate liquid from the heart and serum citrulline, nitrites/nitrates were decreased in MS and AGE increased them (p < 0.01). In conclusion, AGE reduces MS-induced cardiovascular risk, through its anti-oxidant properties.


Assuntos
Antioxidantes/administração & dosagem , Alho/química , Testes de Função Cardíaca/efeitos dos fármacos , Síndrome Metabólica/tratamento farmacológico , Extratos Vegetais/administração & dosagem , Animais , Antioxidantes/farmacologia , Pressão Sanguínea/efeitos dos fármacos , Colesterol/sangue , Modelos Animais de Doenças , Produtos Finais de Glicação Avançada/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Síndrome Metabólica/fisiopatologia , Extratos Vegetais/farmacologia , Ratos , Ratos Wistar , Triglicerídeos/sangue
11.
Rev. neurol. (Ed. impr.) ; 62(9): 403-407, 1 mayo, 2016. ilus, graf
Artigo em Espanhol | IBECS | ID: ibc-151861

RESUMO

Introducción. El reflejo venoarteriolar (RVA) lo provoca un incremento en la presión venosa transmural al colocar una parte del cuerpo en el sentido de la aceleración gravitatoria por debajo del corazón. Objetivo. Evaluar el RVA en sujetos sanos al levantar una parte del cuerpo por encima del corazón. Sujetos y métodos. En 16 sujetos sanos (20-65 años) se estudió el RVA mediante cambios en el flujo sanguíneo de la piel con un fotopletismógrafo digital infrarrojo colocado en el pulpejo en sujetos sanos durante las siguientes condiciones: brazo derecho a la altura del corazón, brazo derecho 40 cm por debajo del corazón y brazo derecho 40 cm por encima del corazón. Las variables medidas fueron: amplitud del flujo sanguíneo de la piel con el brazo a la altura del corazón (amplitud basal), porcentaje de disminución del flujo sanguíneo de la piel con el brazo por debajo del corazón y porcentaje de aumento del flujo sanguíneo de la piel con el brazo por encima del corazón. Resultados. El porcentaje de vasoconstricción con el brazo derecho por debajo del corazón fue del 35%, y el de vasodilatación, del 50%. Conclusiones. La evaluación del RVA con el brazo por debajo del corazón provoca vasoconstricción, y la elevación del brazo produce una importante vasodilatación. La vasoconstricción y la vasodilatación se mantienen mientras la extremidad se mantenga por encima o por debajo del corazón. Éste es un estudio potencialmente muy útil y económico para estudiar la inervación de la microcirculación en diversas neuropatías periféricas de fibras delgadas y mixtas (AU)


Introduction. The veno-arteriolar reflex (VAR) is triggered by an increase in the transmural venous pressure on placing a part of the body in the same direction as the gravitational acceleration below the heart. Aim. To assess the VAR in healthy subjects on raising a part of the body above the level of the heart. Subjects and methods. VAR was studied in 16 healthy subjects (20-65 years old) by means of changes in the blood flow in the skin detected using a digital infrared photoplethysmograph attached to the fingertip under the following conditions: right arm at the height of the heart, right arm below the heart and right arm below the level of the heart. The variables measured were: amplitude of the blood flow in the skin with the arm raised to the height of the heart (baseline amplitude), percentage decrease of the blood flow in the skin with the arm below the heart and percentage increase in blood flow with the arm above the heart. Results. The percentage of vasoconstriction with the right arm below the heart was 35%, and that of vasodilation, 50%. Conclusions. Evaluation of the VAR with the arm below the heart causes vasoconstriction, and elevation of the arm causes an important degree of vasodilation. Vasoconstriction and vasodilation are maintained while the limb is kept above or below the heart. This is an economical and potentially very useful way of studying the innervation of the microcirculation in a number of different peripheral neuropathies of thin and mixed fibres (AU)


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Vasoconstrição/fisiologia , Vasodilatação/fisiologia , Microcirculação/fisiologia , Arteríolas/lesões , Arteríolas/patologia , Homeostase/fisiologia , Sistema Nervoso Autônomo/lesões , Sistema Nervoso Autônomo/patologia , Sistema Nervoso Autônomo/fisiologia , Sistema Nervoso Simpático/lesões , Sistema Nervoso Simpático/patologia , Sistema Nervoso Simpático/fisiologia , Fotopletismografia/instrumentação , Fotopletismografia/métodos , Fotopletismografia , Ultrassonografia Doppler/instrumentação , Ultrassonografia Doppler/métodos , Ultrassonografia Doppler , Termografia/instrumentação , Termografia/métodos , Termografia
12.
Physiol Rep ; 4(24)2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-28039403

RESUMO

Myogenic vascular response is a form of systemic and regional vasoconstriction produced increasing the intra-arterial pressure by gravity. Here, the vasoconstriction due to the myogenic response, induced by the gravitational action in a dependent limb, is separated from that caused by the baroreceptor reflex. Regional changes of skin blood flow (SBF), total blood volume of the finger (TBVF), pulse pressure (PP), heart rate (HR), systolic, and diastolic blood pressure (BP) were analyzed in 10 healthy young subjects in supine and upright positions. By lowering the arm in supine position, SBF decreased compared to its basal measurement, PR increased, and PP contracted, indicating arterial vasoconstriction that rise BP TBVF increased, demonstrating an increment in venous volume. HR did not change, reflecting no action of the baroreceptor reflex. In upright position with lowered arm, there was an additional increase in BP variables, demonstrating vasoconstriction. Moreover, BP and HR showed oscillations at 0.1 Hz reflecting the entrance of the baroreceptor reflex. The action of gravity in a dependent limb in supine position induces a regional vasoconstriction and an increase of BP due to activation of the myogenic response, while the baroreceptor reflex or other neural factors do not appear to operate. In the upright position with the arm dependent, there is a further increase in regional vasoconstriction and BP with reciprocal changes in HR, indicating the entrance of the baroreceptor superimposed to the myogenic response. This study demonstrates that the myogenic and baroreceptor vasoconstriction can be separated in vivo.


Assuntos
Barorreflexo , Postura , Decúbito Dorsal , Vasoconstrição , Adulto , Pressão Sanguínea , Gravitação , Frequência Cardíaca , Humanos , Pele/irrigação sanguínea , Adulto Jovem
13.
Artif Organs ; 40(7): 684-91, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26582542

RESUMO

Hemodialysis (HD) is usually performed with the gradually decreasing ultrafiltration rate (UFR) profile (dUFR). The aim of the present study was to compare the hemodynamic response to HD with the dUFR to that of HD with the gradually increasing UFR profile (iUFR). The study population included 10 patients (three women, mean age: 28 ± 8 years) undergoing maintenance HD who had reached dry weight without taking antihypertensive medications. Each patient received (in random order) one HD session with the dUFR and another with the iUFR (both with 3 h total UFR = 2200 mL). Hemodynamic response was evaluated with a brachial blood pressure (BP) monitor, echocardiogram and Portapres to measure digital BP, heart rate, cardiac output, stroke volume, and peripheral resistance. Mean values were compared at each HD hour during the first 3 h of a 4-h HD session. The HD characteristics, including Kt/V, were similar for both UFR profiles. Relative blood volume decreased more gradually and linearly with the iUFR. Hemodynamic variables were not significantly different between the two profiles, but brachial BP was more stable with the iUFR. Digital diastolic BP increased with both profiles. Peripheral resistance increased with both profiles, and tended to increase more with the iUFR. Echocardiographic variables changed similarly during the HD session with both profiles. In conclusion, these two UFR profiles are similar in most hemodynamic variables. The statistical equivalence of both profiles suggests that either could be prescribed based on the clinical characteristics of the patient.


Assuntos
Hemodinâmica , Diálise Renal/métodos , Ultrafiltração/métodos , Adulto , Pressão Sanguínea , Débito Cardíaco , Feminino , Frequência Cardíaca , Humanos , Masculino , Adulto Jovem
14.
Arq Neuropsiquiatr ; 72(10): 762-7, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25337727

RESUMO

UNLABELLED: Cardiovascular variability (CVV) has been evaluated in patients with Parkinson's disease (PD) in other countries and exhibit ethnic differences. OBJECTIVE: We investigated heart rate variability (HRV) and blood pressure variability (BPV) in Mexican patients with PD. METHOD: We further compared HRV and BPV between this group and young healthy controls (YHC) in order to estimate, for the first time in our country, the magnitude of the difference. Twenty patients were examined. Time- and frequency-domain CVV parameters were studied during supine rest (SR), active standing (AS) and controlled breathing. These measurements were compared to those of 20 YHC. RESULTS: In the three conditions tested, our study showed a decrease in almost all HRV parameters in PD patients; on the contrary, decreased BPV parameters were found less frequently and only during SR and AS. CONCLUSION: Our results indicate that HRV is impaired in PD. Some BPV parameters are also diminished.


Assuntos
Pressão Sanguínea/fisiologia , Frequência Cardíaca/fisiologia , Doença de Parkinson/fisiopatologia , Estudos de Casos e Controles , Eletrocardiografia , Feminino , Humanos , Masculino , México , Pessoa de Meia-Idade
15.
Arq. neuropsiquiatr ; 72(10): 762-767, 10/2014. tab, graf
Artigo em Inglês | LILACS | ID: lil-725335

RESUMO

Cardiovascular variability (CVV) has been evaluated in patients with Parkinson's disease (PD) in other countries and exhibit ethnic differences. Objective We investigated heart rate variability (HRV) and blood pressure variability (BPV) in Mexican patients with PD. Method We further compared HRV and BPV between this group and young healthy controls (YHC) in order to estimate, for the first time in our country, the magnitude of the difference. Twenty patients were examined. Time- and frequency-domain CVV parameters were studied during supine rest (SR), active standing (AS) and controlled breathing. These measurements were compared to those of 20 YHC. Results In the three conditions tested, our study showed a decrease in almost all HRV parameters in PD patients; on the contrary, decreased BPV parameters were found less frequently and only during SR and AS. Conclusion Our results indicate that HRV is impaired in PD. Some BPV parameters are also diminished. .


A variabilidade cardiovascular (VCV) tem sido avaliada em doentes parkinsonianos em vários países e apresenta diferenças étnicas. Objetivo Investigar a variabilidade da frequência cardíaca (VFC) e a variabilidade da pressão arterial (VPA) em doentes parkinsonianos mexicanos. Método Comparamos VFC e VPA entre o grupo de estudo e controles jovens (CJ), a fim de estimar a magnitude da diferença. CVV foi estudada no domínio do tempo e da frequência durante repouso supino (RS), ortostase ativa (OA) e respiração controlada. Estas medições foram comparadas com aquelas de 20 CJ. Resultados Nosso estudo mostrou diminuição em quase todos os parâmetros da VFC em doentes parkinsonianos. A diminuição dos parâmetros da VPA foi encontrada com menos frequência. Conclusão Nossos resultados indicam que a VFC é prejudicada na doença de Parkinson. Alguns parâmetros do VPA também são reduzidos. .


Assuntos
Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pressão Sanguínea/fisiologia , Frequência Cardíaca/fisiologia , Doença de Parkinson/fisiopatologia , Estudos de Casos e Controles , Eletrocardiografia , México
16.
Clin Exp Hypertens ; 36(3): 123-31, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-23734849

RESUMO

We investigated the effects of Hibiscus sabdariffa Linnaeus (HSL)-fed infusion on the fatty acid (FA) profile in liver of metabolic syndrome (MS) rats and its possible effect on vascular reactivity. Body mass, intra-abdominal fat, triglycerides, insulin, blood pressure, saturated, monounsaturated FA, NEFAs, Δ(9)-, Δ(6)-desaturases and vasoconstriction were increased, while vasorelaxation, polyunsaturated FA, endothelial nitric oxide and [Formula: see text]/[Formula: see text] ratio decreased in MS versus Control, but HSL infusion modified it and increased Δ(5)-desaturase. The results suggest that the alteration in FA liver metabolism in the MS contributes to impaired vascular reactivity, but treatment with of HSL infusion can improve this condition.


Assuntos
Ácidos Graxos/metabolismo , Hibiscus/química , Fígado/metabolismo , Síndrome Metabólica/tratamento farmacológico , Fitoterapia , Preparações de Plantas/uso terapêutico , Vasodilatação/efeitos dos fármacos , Animais , Insulina/sangue , Gordura Intra-Abdominal/metabolismo , Fígado/irrigação sanguínea , Fígado/efeitos dos fármacos , Masculino , Síndrome Metabólica/metabolismo , Ratos , Triglicerídeos/sangue
17.
Cardiol Res Pract ; 2013: 603913, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24222884

RESUMO

Background. Ivabradine is an If ion current inhibitor that has proved to reduce mortality in patients with systolic heart failure by slowing heart rate without decreasing myocardial contractility. Photoplethysmography is a simple, low-cost optical technique that can evaluate vascular function and detect changes in blood flow, pulse, and swelling of tissular microvascular space. Objective. To evaluate the effect of ivabradine on endothelial function by photoplethysmography in diastolic and right heart failure patients. Methodology. 15 patients were included (mean age of 78.1 ± 9.2 years) with optimally treated diastolic and right heart failure. They underwent photoplethysmography before and after induced ischemia to evaluate the wave blood flow on the finger, using the maximum amplitude time/total time (MAT/TT) index. Two measurements were made before and after oral Ivabradine (mean 12.5 mg a day during 6 months of followup). Results. In the study group, the MAT/TT index was 29.1 ± 2.2 versus 24.3 ± 3.2 (P = 0.05) in basal recording and 30.4 ± 2.1 versus 23.3 ± 2.9 (P = 0.002), before versus after ischemia and before versus after Ivabradine intervention, respectively. Conclusions. Ivabradine administration improves endothelial function (shear stress) in diastolic and right heart failure patients.

18.
Cardiol J ; 19(6): 612-7, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23224924

RESUMO

BACKGROUND: The utility of L-arginine and L-citrulline in treatment of arterial hypertension by increasing vascular oxide nitric availability has been demonstrated. Photoplethysmography, a simple and low-cost optical technique, makes it possible to assess vascular function and to detect changes in blood flow, pulse and swelling of the microvascular tissular space. The aim of the study was to evaluate the effect of L-citrulline supplementation on functional class, ejection fraction and peripheral blood flow in patients with systolic heart failure. METHODS: Thirty-five stable outpatients attending the Heart Failure Clinic at the INCMNSZ underwent clinical evaluation, radioisotopic ventriculography and photoplethysmography before and at the end of 4 months. They were randomized into two groups: experimental group, with oral L-citrulline supplementation (3 g/day, n = 20) and control group, without supplementation (n = 15). RESULTS: In the experimental group the left ventricular ejection fraction (LVEF) increased 20.3% at rest and 12.7% with stress, as well as the right ventricular ejection fraction at rest of 15.10% and 14.88% with stress. In addition, functional class improved in 35%, and the maximum amplitude time/total time (MAT/TT) index decreased 23.1%. These changes were statistically significant compared with the control group. CONCLUSIONS: Citrulline supplementation significantly improved the LVEF, the endothelial function (MAT/TT index) and functional class. Citrulline can be an important co-adjuvant in the treatment of stable and stable systolic heart failure patients.


Assuntos
Arginina/administração & dosagem , Citrulina/administração & dosagem , Suplementos Nutricionais , Insuficiência Cardíaca Sistólica/tratamento farmacológico , Função Ventricular Esquerda/efeitos dos fármacos , Administração Oral , Idoso , Estudos de Casos e Controles , Endotélio Vascular/efeitos dos fármacos , Feminino , Seguimentos , Insuficiência Cardíaca Sistólica/diagnóstico por imagem , Insuficiência Cardíaca Sistólica/fisiopatologia , Hemodinâmica/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Óxido Nítrico/sangue , Pacientes Ambulatoriais , Fotopletismografia , Cintilografia , Volume Sistólico/efeitos dos fármacos , Resultado do Tratamento
19.
Arch Cardiol Mex ; 82(3): 197-203, 2012.
Artigo em Espanhol | MEDLINE | ID: mdl-23021355

RESUMO

OBJECTIVE: To develop a portable signal monitoring equipment for electrocardiography (ECG) and heart rate (HR), communicated with a mobile phone using the Bluetooth (BT) communication protocol for display of the signal on screen. METHODS: A monitoring system was designed in which the electronic section performs the ECG signal acquisition, as well as amplification, filtering, analog to digital conversion and transmission of the ECG and HR using BT. Two programs were developed for the system. The first one calculates HR through QRS identification and sends the ECG signals and HR to the mobile, and the second program is an application to acquire and display them on the mobile screen. RESULTS: We developed a portable electronic system powered by a 9 volt battery, with amplification and bandwidth meeting the international standards for ECG monitoring. The QRS complex identification was performed using the second derivative algorithm, while the programs allow sending and receiving information from the ECG and HR via BT, and viewing it on the mobile screen. The monitoring is feasible within distances of 15 m and it has been tested in various mobiles telephones of brands Nokia®, Sony Ericsson® and Samsung®. CONCLUSIONS: This system shows an alternative for mobile monitoring using BT and Java 2 Micro Edition (J2ME) programming. It allows the register of the ECG trace and HR, and it can be implemented in different phones.


Assuntos
Telefone Celular , Eletrocardiografia Ambulatorial/instrumentação , Frequência Cardíaca , Humanos
20.
Arch. cardiol. Méx ; 82(3): 197-203, jul.-sept. 2012. ilus
Artigo em Espanhol | LILACS | ID: lil-685329

RESUMO

Objetivo: Desarrollar un equipo de monitoreo de señales de electrocardiografía (ECG) y frecuencia cardiaca (FC) portátil, comunicado con un teléfono móvil mediante el protocolo de comunicación Bluetooth (BT), para su visualización en pantalla. Métodos: Se diseñó un sistema de monitoreo que en su sección electrónica realiza la adquisición de la señal de ECG, así como su amplificación, filtrado, conversión analógica a digital y transmisión por BT del ECG y la FC. Se desarrollaron dos programas para el sistema. El primero calcula la FC a través de la identificación del QRS, y envía las señales del ECG y FC al teléfono móvil. El segundo es una aplicación que permite adquirirlas y visualizarlas en la pantalla del móvil. Resultados: Se desarrolló un sistema electrónico portátil alimentado por una batería de 9 volts, de amplificación y ancho de banda que cumplen con los estándares internacionales, para monitoreo de ECG. La identificación del complejo QRS se realizó con el algoritmo de la segunda derivada, mientras que los programas realizados permiten enviar y recibir la información del ECG y la FC a través de BT, para visualizarlos en la pantalla del móvil. El monitoreo es factible hasta 15 m de distancia. Se probó en distintos móviles de Nokia®, Sony Ericsson® y Samsung®. Conclusiones: Este sistema muestra una alternativa de monitoreo móvil, con un teléfono por medio de BT y la programación en Java 2 Micro Edition (J2ME). Permite registrar el trazo del ECG y la FC, y puede implementarse en diferentes móviles.


Objective: To develop a portable signal monitoring equipment for electrocardiography (ECG) and heart rate (HR), communicated with a mobile phone using the Bluetooth (BT) communication protocol for display of the signal on screen. Methods: A monitoring system was designed in which the electronic section performs the ECG signal acquisition, as well as amplification, filtering, analog to digital conversion and transmission of the ECG and HR using BT. Two programs were developed for the system. The first one calculates HR through QRS identification and sends the ECG signals and HR to the mobile, and the second program is an application to acquire and display them on the mobile screen. Results: We developed a portable electronic system powered by a 9 volt battery, with amplification and bandwidth meeting the international standards for ECG monitoring. The QRS complex identification was performed using the second derivative algorithm, while the programs allow sending and receiving information from the ECG and HR via BT, and viewing it on the mobile screen. The monitoring is feasible within distances of 15 m and it has been tested in various mobiles telephones of brands Nokia®, Sony Ericsson® and Samsung®. Conclusions: This system shows an alternative for mobile monitoring using BT and Java 2 Micro Edition (J2ME) programming. It allows the register of the ECG trace and HR, and it can be implemented in different phones.


Assuntos
Humanos , Telefone Celular , Eletrocardiografia Ambulatorial/instrumentação , Frequência Cardíaca
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