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1.
BMC Pregnancy Childbirth ; 21(1): 805, 2021 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-34863125

RESUMO

BACKGROUND: To evaluate the performance of the Fetal Medicine Foundation (FMF) preterm preeclampsia (PE) screening algorithm in an indigenous South Asian population. METHODS: This was a prospective observational cohort study conducted in a tertiary maternal fetal unit in Delhi, India over 2 years. The study population comprised of 1863 women carrying a singleton pregnancy and of South Asian ethnicity who were screened for preterm pre-eclampsia (PE) between 11 and 14 weeks of gestation using Mean Arterial Pressure (MAP), transvaginal Mean Uterine Artery Pulsatility Index (UtAPI) and biochemical markers - Pregnancy Associated Plasma Protein-A (PAPP-A) and Placental Growth Factor.. Absolutemeasurements of noted biomarkers were converted to multiples of the expected gestational median (MoMS) which were then used to estimate risk for preterm PE < 37 weeks using Astraia software. Women with preterm PE risk of ≥1:100 was classified as as high risk. Detection rates (DR) at 10% false positive rate were calculated after adjusting for prophylactic aspirin use (either 75 or 150 mg). RESULTS: The incidence of PE and preterm PE were 3.17% (59/1863) and 1.34% (25/1863) respectively. PAPP-A and PlGF MoM distribution medians were 0.86 and 0.87 MoM and significantly deviated from 1 MoM. 431 (23.1%) women had a risk of ≥1:100, 75 (17.8%) of who received aspirin. Unadjusted DR using ≥1:100 threshold was 76%.Estimated DRs for a fixed 10% FPR ranged from 52.5 to 80% depending on biomarker combination after recentering MoMs and adjusting for aspirin use. CONCLUSION: The FMF algorithm whilst performing satisfactorily could still be further improved to ensure that biophysical and biochemical markers are correctly adjusted for indigenous South Asian women.


Assuntos
Algoritmos , Programas de Rastreamento/métodos , Pré-Eclâmpsia/diagnóstico , Pré-Eclâmpsia/etnologia , Primeiro Trimestre da Gravidez , Pressão Arterial/fisiologia , Biomarcadores , Estudos de Coortes , Feminino , Fundações , Humanos , Índia/etnologia , Perinatologia , Fator de Crescimento Placentário/metabolismo , Gravidez , Proteína Plasmática A Associada à Gravidez/metabolismo , Estudos Prospectivos , Fluxo Pulsátil/fisiologia , Risco
2.
Undersea Hyperb Med ; 48(2): 157-168, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33975406

RESUMO

Introduction: Safe administration of critical care hyperbaric medicine requires specialized equipment and advanced training. Equipment must be tested in order to evaluate function in the hyperbaric environment. High-frequency percussive ventilation (HFPV) has been used in intensive care settings effectively, but it has never been tested in a hyperbaric chamber. Methods: Following a modified U.S. Navy testing protocol used to evaluate hyperbaric ventilators, we evaluated an HFPV transport ventilator in a multiplace hyperbaric chamber at 1.0, 1.9, and 2.8 atmospheres absolute (ATA). We used a test lung with analytical software for data collection. The ventilator uses simultaneous cyclic pressure-controlled ventilation at a pulsatile flow rate (PFR)/oscillatory continuous positive airway pressure (oCPAP) ratio of 30/10 with a high-frequency oscillation percussive rate of 500 beats per minute. Inspiratory and expiratory times were maintained at two seconds throughout each breathing cycle. Results: During manned studies, the PFR/oCPAP ratios were 26/6, 22/7, and 22.5/8 at an airway resistance of 20cm H2O/L/second and 18/9, 15.2/8.5, and 13.6/7 at an airway resistance of 50 cm/H2O/L/second at 1, 1.9, and 2.8 ATA. The resulting release volumes were 800, 547, and 513 mL at airway resistance of 20 cm H2O/L/sec and 400, 253, and 180 mL at airway resistance of 50 cm/H2O/L/sec at 1, 1.9, and 2.8 ATA. Unmanned testing showed similar changes. The mean airway pressure (MAP) remained stable throughout all test conditions; theoretically, supporting adequate lung recruitment and gas exchange. A case where HFPV was used to treat a patient for CO poisoning was presented to illustrate that HFPV worked well under HBO2 conditions and no complications occurred during HBO2 treatment. Conclusion: The HFPV transport ventilator performed adequately under hyperbaric conditions and should be considered a viable option for hyperbaric critical care. This ventilator has atypical terminology and produces unique pulmonary physiology, thus requiring specialized training prior to use.


Assuntos
Ventilação de Alta Frequência/instrumentação , Oxigenoterapia Hiperbárica/instrumentação , Lesão por Inalação de Fumaça/terapia , Ventiladores Mecânicos , Acidose/etiologia , Idoso , Resistência das Vias Respiratórias , Pressão Atmosférica , Intoxicação por Monóxido de Carbono/complicações , Feminino , Ventilação de Alta Frequência/métodos , Humanos , Oxigenoterapia Hiperbárica/métodos , Pulmão/fisiologia , Respiração com Pressão Positiva/instrumentação , Respiração com Pressão Positiva/métodos , Troca Gasosa Pulmonar/fisiologia , Fluxo Pulsátil , Valores de Referência , Respiração
3.
Ann Vasc Surg ; 71: 308-314, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32768540

RESUMO

BACKGROUND: Neuromuscular electrical stimulator (NMES) devices increase blood flow to the lower limb by a process of intermittent muscular contraction initiated by a transdermal stimulus to the common peroneal nerve. However, its effects on localized microvascular blood supply to lower limb wounds are unknown. This study is a single-center open label study measuring the effect of neuromuscular stimulation of the common peroneal nerve on the microvascular blood flow within the wound bed of arterial leg ulcers. METHODS: Eights patients with ischemic lower limb wounds had an NMES (geko™) applied to the common peroneal nerve. Baseline and intervention analysis of blood flow to the wound bed and edge was performed using Laser Speckle Contrast Imaging. Mean flow (flux) and pulse amplitude (pulsatility) were measured. RESULTS: Stimulation of the common peroneal nerve with the NMES resulted in a significantly increased flux and pulsatility in both the wound bed and the wound edge in all 8 patients. CONCLUSIONS: Neuromuscular electrical stimulation immediately increases microcirculatory blood flow to the wound bed and edge in patients with ischemic lower limb wounds. These data may provide mechanistic insight into the clinical efficacy of NMES in healing wounds. www.clinicaltrials.gov NCT03186560.


Assuntos
Terapia por Estimulação Elétrica , Úlcera da Perna/terapia , Extremidade Inferior/irrigação sanguínea , Extremidade Inferior/inervação , Microcirculação , Nervo Fibular , Idoso , Idoso de 80 Anos ou mais , Terapia por Estimulação Elétrica/efeitos adversos , Feminino , Humanos , Imagem de Contraste de Manchas a Laser , Úlcera da Perna/diagnóstico por imagem , Úlcera da Perna/fisiopatologia , Masculino , Pessoa de Meia-Idade , Fluxo Pulsátil , Fluxo Sanguíneo Regional , Resultado do Tratamento , Cicatrização
4.
Medicine (Baltimore) ; 99(11): e19501, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32176092

RESUMO

BACKGROUND: Clinical and basic research supports that blood glucose fluctuation is an important predictor of diabetic vascular disease and an etiology of lower extremity atherosclerosis, which is an important pathological basis for lower extremity vascular diseases. Previous Chinese National Natural Science Foundation trials (No. 81503566) have reported that the traditional Chinese medicine Shenqi compound can reduce blood glucose fluctuation and low-grade inflammation, and protect blood vessels; however, there are no high-quality clinical evidences available to support the same. This multicenter randomized controlled trial aims to obtain more clinical evidence to confirm the efficacy and safety of Shenqi compound in type 2 diabetes with lower extremity atherosclerosis. METHODS: A multicenter RCT will be implemented in this study for a 32-week study period (8 weeks for intervention and 24 weeks for follow-up). Participants will be recruited from the Teaching Hospital of Chengdu University of TCM, Mianyang Hospital of TCM, and Shuangliu Hospital of TCM. Sixty participants will be randomly divided into a treatment group (basic treatment combined with traditional Chinese medicine Shenqi Compound) or a control group (basic treatment combined with Chinese medicine placebo) with 30 participants in each group. Patients will be selected considering the following inclusion criteria: age between 35 and 65 years, and a positive diagnosis for type 2 diabetes with lower extremity atherosclerosis and TCM syndromes. Primary outcome indicator is an arterial color Doppler ultrasound. Secondary outcome indicators include: blood glucose fluctuation indicators (MBG, SDBG, LAGE), islet ß-cell function evaluation indicators (Homa-IR, Homa-islet, SG, SCP), inflammation indicators (NLR, CRP, IL-6), blood lipids, and HbA1c. Safety index includes vital signs (T, P, R, BP), blood, urine, stool routine, liver and renal function, electrocardiogram, and adverse event records. The endpoint event is defined as the presence of gangrene in the lower limbs. DISCUSSION: Explore the clinical effect of traditional Chinese medicine "Shenqi Compound" to reduce blood glucose fluctuation and use HOMA-IR, the area under the glucose curve, and the area under the C-peptide curve to evaluate the effect of protecting islet ß cell function. TRIAL REGISTRATION: Chinese clinical trial registry (ChiCTR-1900027693). Registered on November 23, 2019. http://www.chictr.org.cn.


Assuntos
Aterosclerose/tratamento farmacológico , Diabetes Mellitus Tipo 2 , Angiopatias Diabéticas/tratamento farmacológico , Medicamentos de Ervas Chinesas/uso terapêutico , Hipoglicemiantes/uso terapêutico , Extremidade Inferior/irrigação sanguínea , Medicina Tradicional Chinesa , Aterosclerose/sangue , Aterosclerose/fisiopatologia , Glicemia , China , Angiopatias Diabéticas/sangue , Angiopatias Diabéticas/fisiopatologia , Medicamentos de Ervas Chinesas/administração & dosagem , Humanos , Hipoglicemiantes/administração & dosagem , Fitoterapia , Fluxo Pulsátil , Ensaios Clínicos Controlados Aleatórios como Assunto , Fluxo Sanguíneo Regional , Projetos de Pesquisa
5.
Climacteric ; 23(3): 245-251, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31691621

RESUMO

Objective: This study aimed to assess the effects of daily use of Cimicifuga racemosa on endothelial function through flow-mediated dilation of the brachial artery, when used for 28 days by healthy postmenopausal women.Methods: The double-blind, randomized, placebo-controlled study included two groups of postmenopausal women (n = 31 each). The subjects were clinically assessed and flow-mediated dilation of the brachial artery was measured before and after 28 days of treatment. Patients received dry extract corresponding to 160 mg C. racemosa (extract with 4 mg of triterpene glycosides) or placebo.Results: Mean age, time since menopause, and body mass index in the two groups were similar. The measurements of flow-mediated dilation of the brachial artery, pre and post treatment, respectively, showed a significant increase in patients who used C. racemosa (p = 0.006), unlike patients who used placebo, who did not present changes in the outcome of flow-mediated dilation of the brachial artery after 28 days of use (p ≥ 0.05). When comparing the number of women in both groups who showed an increase in flow-mediated dilation, a significant difference was found in the measurements of the treated group after the use of the medication (p = 0.018).Conclusions: Daily use of 160 mg C. racemosa extract by postmenopausal women for 28 days beneficially influences endothelial function by promoting elasticity of the brachial artery.


Assuntos
Artéria Braquial/fisiologia , Cimicifuga , Fogachos/tratamento farmacológico , Extratos Vegetais/uso terapêutico , Vasodilatadores/uso terapêutico , Velocidade do Fluxo Sanguíneo , Método Duplo-Cego , Endotélio Vascular/efeitos dos fármacos , Feminino , Humanos , Pessoa de Meia-Idade , Fitoterapia , Extratos Vegetais/farmacologia , Estudos Prospectivos , Fluxo Pulsátil , Resultado do Tratamento , Vasodilatadores/farmacologia
6.
J Matern Fetal Neonatal Med ; 33(10): 1631-1637, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-30345864

RESUMO

Background: Severe intrauterine growth restriction complicates approximately 0.4% of the pregnancies. It increases the risk of perinatal morbidity and mortality.Subjects and methods: A double blind placebo controlled trial was conducted in Beni Suef University hospitals during 2017. It included 46 pregnant women with severe intrauterine growth restriction. Women were randomly allocated into two groups each included 23 patients. Intervention group received sildenafil citrate 20 mg orally three times a day, in addition to fish oil and zinc supplementation. Control group received tablets similar to sildenafil and the same treatment as intervention group. Primary outcomes included improvement in umbilical and middle cerebral arteries pulsatility indices and abdominal circumference.Results: Umbilical and middle cerebral arteries Doppler indices showed significant difference between groups after intake of sildenafil. Umbilical artery pulsatility index decreased significantly (p value = .001) while middle cerebral artery pulsatility index increased significantly in intervention group (p value0.001). Moreover, abdominal circumference growth velocity improved after two weeks of sildenafil intake (p value = .001).Conclusions: Sildenafil citrate may improve uteroplacental and fetal cerebral perfusion in pregnancies complicated by severe intrauterine growth restriction. It also improves abdominal circumference growth velocity. A wide scale randomized trials are needed for evaluation of neonatal and long term morbidity and mortality outcomes of pregnancies treated by sildenafil citrate.


Assuntos
Retardo do Crescimento Fetal/tratamento farmacológico , Citrato de Sildenafila/administração & dosagem , Vasodilatadores/administração & dosagem , Administração Oral , Adulto , Peso ao Nascer , Método Duplo-Cego , Egito , Feminino , Óleos de Peixe/uso terapêutico , Humanos , Recém-Nascido , Artéria Cerebral Média/diagnóstico por imagem , Artéria Cerebral Média/efeitos dos fármacos , Placenta/irrigação sanguínea , Placenta/efeitos dos fármacos , Gravidez , Fluxo Pulsátil , Citrato de Sildenafila/efeitos adversos , Ultrassonografia Pré-Natal , Artérias Umbilicais/diagnóstico por imagem , Artérias Umbilicais/efeitos dos fármacos , Vasodilatadores/efeitos adversos , Zinco/administração & dosagem
7.
J Manipulative Physiol Ther ; 42(1): 66-74, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30955908

RESUMO

OBJECTIVE: The purpose of this study was to explore vertebral artery hemodynamic changes associated with McKenzie therapeutic cervical movements in healthy individuals. METHODS: A single-group repeated-measure design was used to examine 20 healthy participants aged 22.05 (1.69) years, mean (standard deviation). Vertebral artery volume flow, diameter, resistive index, time-averaged maximum velocity, and pulsatility index were measured using Duplex ultrasound. Vertebral artery hemodynamics were measured at cervical neutral positions then compared against vertebral artery hemodynamics measured during end-range loading and after repeated McKenzie therapeutic movements. Wilcoxon signed rank tests were used for comparisons, and standardized mean differences (SMDs) were calculated to quantify the changes in size. RESULTS: Repeated retraction with extension in a sitting position and end-range retraction with extension in supine position were significantly associated with an increase in vertebral artery volume flow, P ≤ .01, and the SMD suggests small-medium changes in size. Statistical significant vertebral artery dilation was observed in the sitting position with protraction, combined retraction with extension, and flexion, P ≤ .01, yet the SMD suggested small changes in size. End-range flexion was significantly associated with a reduction in vertebral artery pulsatility index, and the SMD suggested large changes in size. Repeated retraction with extension in supine position was significantly associated with an increase in vertebral artery time-averaged maximum velocity, yet the SMD revealed no clinically important difference. CONCLUSION: For the healthy participants in this study, McKenzie cervical movements were mostly associated with an increase in vertebral artery hemodynamics.


Assuntos
Velocidade do Fluxo Sanguíneo/fisiologia , Manipulação da Coluna/métodos , Fluxo Pulsátil/fisiologia , Fluxo Sanguíneo Regional/fisiologia , Artéria Vertebral/diagnóstico por imagem , Artéria Vertebral/fisiologia , Vértebras Cervicais , Feminino , Voluntários Saudáveis , Humanos , Masculino , Decúbito Dorsal , Ultrassonografia Doppler Dupla , Adulto Jovem
8.
Ultrasound Obstet Gynecol ; 53(4): 454-464, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30126005

RESUMO

OBJECTIVE: To assess studies reporting reference ranges for umbilical artery (UA) and fetal middle cerebral artery (MCA) Doppler indices and cerebroplacental ratio (CPR), using a set of predefined methodological quality criteria for study design, statistical analysis and reporting methods. METHODS: This was a systematic review of observational studies in which the primary aim was to create reference ranges for UA and MCA Doppler indices and CPR in fetuses of singleton gestations. A search for relevant articles was performed in MEDLINE, EMBASE, CINAHL, Web of Science (from inception to 31 December 2016) and references of the retrieved articles. Two authors independently selected studies, assessed the risk of bias and extracted the data. Studies were scored against a predefined set of independently agreed methodological criteria and an overall quality score was assigned to each study. Linear multiple regression analysis assessing the association between quality scores and study characteristics was performed. RESULTS: Thirty-eight studies met the inclusion criteria. The highest potential for bias was noted in the following fields: 'ultrasound quality control measures', in which only two studies demonstrated a comprehensive quality-control strategy; 'number of measurements taken for each Doppler variable', which was apparent in only three studies; 'sonographer experience', in which no study on CPR reported clearly the experience or training of the sonographers, while only three studies on UA Doppler and four on MCA Doppler did; and 'blinding of measurements', in which only one study, on UA Doppler, reported that sonographers were blinded to the measurement recorded during the examination. Sample size estimations were present in only seven studies. No predictors of quality were found on multiple regression analysis. Reference ranges varied significantly with important clinical implications for what is considered normal or abnormal, even when restricting the analysis to the highest scoring studies. CONCLUSIONS: There is considerable methodological heterogeneity in studies reporting reference ranges for UA and MCA Doppler indices and CPR, and the resulting references have important implications for clinical practice. There is a need for the standardization of methodologies for Doppler velocimetry and for the development of reference standards, which can be correctly interpreted and applied in clinical practice. We propose a set of recommendations for this purpose. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.


Intervalos de referencia para los índices Doppler de la arterias umbilical y cerebral media del feto y la relación cerebroplacentaria: una revisión sistemática OBJETIVO: Evaluar los estudios que informan sobre intervalos de referencia para los índices Doppler y la relación cerebroplacentaria (RCP) de la arteria umbilical (AU) y la arteria cerebral media (ACM) del feto, mediante un conjunto de criterios de calidad metodológica predefinidos para el diseño del estudio, el análisis estadístico y los métodos de notificación. MÉTODOS: Esta fue una revisión sistemática de estudios observacionales en los que el objetivo principal fue crear intervalos de referencia para los índices Doppler de la AU y la ACM y la RCP de fetos de gestaciones con feto único. Se realizó una búsqueda de artículos relevantes en MEDLINE, EMBASE, CINAHL, Web of Science (desde el inicio hasta el 31 de diciembre de 2016) y en las referencias de los artículos recuperados. Dos autores, de forma independiente, seleccionaron los estudios, evaluaron el riesgo de sesgo y extrajeron los datos. Los estudios se calificaron según un conjunto predefinido de criterios metodológicos acordados de forma independiente y se asignó una puntuación de calidad global a cada estudio. Se realizó un análisis de regresión múltiple lineal para evaluar la asociación entre las puntuaciones de calidad y las características del estudio. RESULTADOS: Un total de 38 estudios cumplieron los criterios de inclusión. El mayor potencial de sesgo se observó en los siguientes casos: 'medidas de control de calidad del ultrasonido', donde sólo dos estudios demostraron una estrategia integral de control de calidad; 'número de mediciones tomadas para cada variable Doppler', que solo fue aparente en tres estudios; 'experiencia del ecografista', puesto que ningún estudio sobre la RCP informó claramente sobre la experiencia o la formación de los ecografistas, y tan solo lo hicieron tres estudios sobre el Doppler de la AU y cuatro sobre el Doppler de la ACM; y 'mediciones a ciegas', donde tan sólo un estudio sobre el Doppler de la AU comunicó que los ecografistas no tuvieron acceso a la medición registrada durante el estudio. Las estimaciones del tamaño de la muestra sólo se comunicaron en siete estudios. No se encontraron predictores de calidad en el análisis de regresión múltiple. Los intervalos de referencia variaron significativamente con implicaciones clínicas importantes para lo que se considera normal o anómalo, incluso cuando se restringió el análisis a los estudios con mayor puntuación. CONCLUSIONES: Existe una heterogeneidad metodológica considerable en los estudios que informan sobre los intervalos de referencia para los índices Doppler de la AU y la ACM y la RCP, y las referencias resultantes tienen implicaciones importantes para la práctica clínica. Es necesario estandarizar las metodologías de la velocimetría Doppler y desarrollar estándares de referencia que puedan ser interpretados y aplicados correctamente en la práctica clínica. Se propone una serie de recomendaciones para este fin.


Assuntos
Artéria Cerebral Média/diagnóstico por imagem , Valor Preditivo dos Testes , Fluxo Pulsátil , Ultrassonografia Doppler , Artérias Umbilicais/diagnóstico por imagem , Feminino , Idade Gestacional , Humanos , Artéria Cerebral Média/embriologia , Estudos Observacionais como Assunto , Variações Dependentes do Observador , Gravidez , Valores de Referência , Ultrassonografia Pré-Natal
9.
Physiol Rep ; 5(10): e13288, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28526782

RESUMO

Previous studies have suggested that the risk of ischemic stroke increases immediately after drinking coffee. Indeed, drinking coffee, that is, caffeine, acutely increases arterial stiffness as well as blood pressure and peripheral vascular resistance. On the other hand, it has been reported that arterial stiffening is associated with elevation in the pulsatility index (PI) of cerebral blood flow (CBF), which increases the risk of brain disease. However, the effect of drinking coffee on the PI of the CBF and its interaction with arterial stiffness remain unknown. Against this background, we hypothesized that an acute increase in arterial stiffness induced by drinking coffee augments cerebral pulsatile stress. To test this hypothesis, in 10 healthy young men we examined the effects of drinking coffee on the PI of middle cerebral artery blood velocity (MCAv) and brachial-ankle pulse wave velocity (baPWV) as indices of cerebral pulsatile stress and arterial stiffness, respectively. Mean arterial blood pressure and baPWV were higher (P < 0.01 and P = 0.02), whereas mean MCAV and mean cerebrovascular conductance index were lower upon drinking coffee (P = 0.02 and P < 0.01) compared with a placebo (decaffeinated coffee). However, there was no difference in the PI of MCAv between drinking coffee and the placebo condition. These findings suggest that drinking coffee does not increase cerebral pulsatile stress acutely despite an elevation in arterial stiffness in the systemic circulation.


Assuntos
Cafeína/administração & dosagem , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/fisiologia , Café , Fluxo Pulsátil/efeitos dos fármacos , Rigidez Vascular/efeitos dos fármacos , Adulto , Índice Tornozelo-Braço , Pressão Arterial/efeitos dos fármacos , Velocidade do Fluxo Sanguíneo/efeitos dos fármacos , Pressão Sanguínea/efeitos dos fármacos , Córtex Cerebral/irrigação sanguínea , Hemodinâmica/efeitos dos fármacos , Humanos , Masculino , Análise de Onda de Pulso , Adulto Jovem
10.
Neurobiol Aging ; 50: 30-38, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27842268

RESUMO

Pulsatile secretion of gonadotropin-releasing hormone (GnRH)/luteinizing hormone (LH) decreases during aging. Kisspeptin (encoded by Kiss1) neurons in the arcuate nucleus coexpress neurokinin B (Tac3) and dynorphin (Pdyn) and are critical for regulating the GnRH/LH pulse. We therefore examined kisspeptin neurons by histochemistry and pulsatile LH release in rats aged 2-3 (Young), 12-13 (Young-Middle), 19-22 (Late-Middle), and 24-26 (Old) months. Total LH concentrations, sampled for 3 hours, decreased in both sexes with aging. In females, numbers of Tac3 and Pdyn neurons were significantly reduced in all aging rats, and numbers of Kiss1 neurons were significantly reduced in Late-Middle and Old rats. In males, numbers of all 3 neuron-types were significantly decreased in all aging rats. GnRH agonist induced LH release in all animals; however, the increased LH concentration in all aging rats was less than that in Young rats. These results suggest that expression of each gene in kisspeptin neurons may be controlled individually during aging, and that reduction of their expression or change in pituitary responsiveness may cause attenuated pulsatile LH secretion.


Assuntos
Envelhecimento/patologia , Envelhecimento/fisiologia , Dinorfinas/metabolismo , Hipotálamo/metabolismo , Kisspeptinas/metabolismo , Hormônio Luteinizante/metabolismo , Neurocinina B/metabolismo , Neurônios/metabolismo , Neurônios/patologia , Animais , Dinorfinas/fisiologia , Feminino , Histocitoquímica , Hipotálamo/citologia , Hipotálamo/patologia , Kisspeptinas/fisiologia , Masculino , Menopausa/metabolismo , Menopausa/fisiologia , Neurocinina B/fisiologia , Neurônios/fisiologia , Fluxo Pulsátil , Ratos Wistar
11.
Am J Obstet Gynecol ; 214(3): 399.e1-8, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26721782

RESUMO

BACKGROUND: In 2012, yoga was practiced by 20 million Americans, of whom 82% were women. A recent literature review on prenatal yoga noted a reduction in some pregnancy complications (ie, preterm birth, lumbar pain, and growth restriction) in those who practiced yoga; to date, there is no evidence on fetal response after yoga. OBJECTIVES: We aimed to characterize the acute changes in maternal and fetal response to prenatal yoga exercises using common standardized tests to assess the well-being of the maternal-fetal unit. STUDY DESIGN: We conducted a single, blinded, randomized controlled trial. Uncomplicated pregnancies between 28 0/7 and 36 6/7 weeks with a nonanomalous singleton fetus of women who did not smoke, use narcotics, or have prior experience with yoga were included. A computer-generated simple randomization sequence with a 1:1 allocation ratio was used to randomize participants into the yoga or control group. Women in the yoga group participated in a 1-time, 1 hour yoga class with a certified instructor who taught a predetermined yoga sequence. In the control group, each participant attended a 1-time, 1 hour PowerPoint presentation by an obstetrician on American Congress of Obstetricians and Gynecologists recommendations for exercise, nutrition, and obesity in pregnancy. All participants underwent pre- and postintervention testing, which consisted of umbilical and uterine artery Doppler ultrasound, nonstress testing, a biophysical profile, maternal blood pressure, and maternal heart rate. A board-certified maternal-fetal medicine specialist, at a different tertiary center, interpreted all nonstress tests and biophysical profile data and was blinded to group assignment and pre- or postintervention testing. The primary outcome was a change in umbilical artery Doppler systolic to diastolic ratio. Sample size calculations indicated 19 women per group would be sufficient to detect this difference in Doppler indices (alpha, 0.05; power, 80%). Data were analyzed using a repeated-measures analysis of variance, a χ(2), and a Fisher exact test. A value of P < .05 was considered significant. RESULTS: Of the 52 women randomized, 46 (88%) completed the study. There was no clinically significant change in umbilical artery systolic to diastolic ratio (P = .34), pulsatility index (P = .53), or resistance index (P = .66) between the 2 groups before and after the intervention. Fetal and maternal heart rate, maternal blood pressure, and uterine artery Dopplers remained unchanged over time. When umbilical artery indices were individually compared with gestational age references, there was no difference between those who improved or worsened between the groups. CONCLUSION: There was no significant change in fetal blood flow acutely after performing yoga for the first time in pregnancy. Yoga can be recommended for low-risk women to begin during pregnancy.


Assuntos
Feto/fisiologia , Artérias Umbilicais/fisiologia , Artéria Uterina/fisiologia , Yoga , Adulto , Pressão Sanguínea , Feminino , Frequência Cardíaca Fetal , Humanos , Movimento , Gravidez , Cuidado Pré-Natal , Fluxo Pulsátil , Método Simples-Cego , Ultrassonografia Doppler , Artérias Umbilicais/diagnóstico por imagem , Artéria Uterina/diagnóstico por imagem , Resistência Vascular , Adulto Jovem
12.
Maturitas ; 82(2): 228-35, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26316026

RESUMO

INTRODUCTION: Hypertension is a major contributor to the global burden of cardiovascular diseases and its prevalence increases progressively with ageing. Therefore the identification of effective, age-friendly exercise and nutritional interventions which lower blood pressure (BP) is a research priority. OBJECTIVE: To undertake a pilot RCT examining the efficacy of isometric handgrip exercise (IHGE) and beetroot juice (a rich source of inorganic nitrate) consumption in modifying clinic and 24-h ambulatory BP (24-h ABP), peripheral arterial function and plasma asymmetric dimethylarginine (ADMA) in older overweight and obese adults. DESIGN: Thirty middle age and older adults (62±5 years) were randomised to: (a) bilateral IHGE at 50% of maximal voluntary contraction (8 min/day), (b) 140 ml/day of concentrated beetroot juice, or (c) no-intervention (control group), for 7 days. All groups followed a standardised diet to control nitrate intake. Clinic and 24-h ABP, peripheral arterial function quantified by pulse wave velocity (PWV) and arterial volume distensibility were assessed before and after intervention. SETTING: Clinical ageing research unit, Newcastle University. RESULTS: At baseline, there were no between-group differences in age, handgrip strength, clinic or 24-h ABP, BMI, waist circumference, fat mass, physical activity level, energy intake or urinary and plasma nitrate concentrations. After intervention, there were no significant effects on clinic systolic and diastolic BP or 24-h ABP, PWV (p=0.54), arterial volume distensibility (p=0.89), or ADMA (p=0.45). CONCLUSIONS: IHGE or beetroot juice consumption for 7 days did not affect BP or peripheral arterial function in overweight and obese middle age and older adults. Ageing may reduce the effects of these interventions on vascular function and studies are needed to test this hypothesis.


Assuntos
Exercício Físico , Força da Mão/fisiologia , Hipertensão/prevenção & controle , Nitratos/administração & dosagem , Fitoterapia , Adulto , Idoso , Envelhecimento , Arginina/análogos & derivados , Arginina/sangue , Beta vulgaris , Pressão Sanguínea , Monitorização Ambulatorial da Pressão Arterial , Suplementos Nutricionais , Feminino , Humanos , Hipertensão/sangue , Hipertensão/fisiopatologia , Masculino , Pessoa de Meia-Idade , Nitratos/sangue , Nitratos/urina , Obesidade/fisiopatologia , Sobrepeso/fisiopatologia , Fluxo Pulsátil , Resultado do Tratamento
13.
Int J Cardiovasc Imaging ; 31(6): 1139-48, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25951915

RESUMO

Recently, left atrial (LA) vortex flow analysis using contrast transesophageal echocardiography (TEE) has been shown to be feasible and has demonstrated significant differences in vortex flow morphology and pulsatility between normal subjects and patients with atrial fibrillation (AF). However, the relationship between LA vortex flow and electrophysiological properties and the clinical significance of LA vortex flow are unknown. The aims of this study were (1) to compare LA vortex flow parameters with LA voltage and (2) to assess the predictive value of LA vortex flow parameters for the recurrence of AF after radiofrequency catheter ablation (RFCA). Thirty-nine patients with symptomatic non-valvular AF underwent contrast TEE before undergoing RFCA for AF. Quantitative LA vortex flow parameters were analyzed by Omega flow (Siemens Medical Solution, Mountain View, CA, USA). The morphology and pulsatility of LA vortex flow were compared with electrophysiologic parameters that were measured invasively. Hemodynamic, electrophysiological, and vortex flow parameters were compared between patients with and without early recurrence of AF after RFCA. Morphologic parameters, including LA vortex depth, length, width, and sphericity index were not associated with LA voltage or hemodynamic parameters. The relative strength (RS), which represents the pulsatility power of LA, was positively correlated with LA voltage (R = 0.53, p = 0.01) and LA appendage flow velocity (R = 0.73, p < 0.001) and negatively correlated with LA volume index (R = -0.56, p < 0.001). Patients with recurrent AF after RFCA showed significantly lower RS (1.7 ± 0.2 vs 1.9 ± 0.4, p = 0.048) and LA voltage (0.9 ± 0.7 vs 1.7 ± 0.8, p = 0.004) than patients without AF recurrence. In the relatively small LA dimension group (LA volume index ≤ 33 ml/m(2)), RS was significantly lower (2.1 ± 0.3 vs 1.7 ± 0.1, p = 0.029) in patients with the recurrent AF. Quantitative LA vortex flow analysis, especially RS, correlated well with LA voltage. Decreased pulsatility strength in the LA was associated with recurrent AF. LA vortex may have incremental value in predicting the recurrence of AF.


Assuntos
Potenciais de Ação , Fibrilação Atrial/diagnóstico , Função do Átrio Esquerdo , Ecocardiografia Doppler em Cores , Ecocardiografia Transesofagiana , Técnicas Eletrofisiológicas Cardíacas , Hemodinâmica , Adulto , Idoso , Fibrilação Atrial/diagnóstico por imagem , Fibrilação Atrial/fisiopatologia , Fibrilação Atrial/cirurgia , Pressão Atrial , Ablação por Cateter , Meios de Contraste , Feminino , Fluorocarbonos , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Projetos Piloto , Valor Preditivo dos Testes , Fluxo Pulsátil , Recidiva , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento
14.
Respir Physiol Neurobiol ; 216: 1-8, 2015 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-26003848

RESUMO

Bubbles nucleate and develop after decompression at active spots on the luminal aspect of ovine large blood vessels. Series of bubbles were shown to detach from the active spot with a mean diameter of 0.7-1.0mm in calm conditions. The effect of mechanical disturbance (striking the bowl containing the vessel or tangential flow) was studied on ovine blood vessels stretched on microscope slides and photographed after hyperbaric exposure. Diameter on detachment after a heavy blow to the bowl was 0.87 ± 0.43 mm (mean ± SD), no different from bubbles which detached without striking the bowl (0.86 ± 0.28 mm). Bubble diameter on detachment during pulsatile tangential flow at 234 cm/min, 0.99 ± 0.36 mm, was not smaller than that seen in the same blood vessels in calm conditions (0.81 ± 0.34 mm). The active spots were stained for lipids, proving their hydrophobicity. The most abundant active spots, which produced only a few bubbles, did not stain for lipids thereafter. The possibility that phospholipids were removed along with detached bubbles may correlate with acclimation to diving. The finding of bubble production at the active spots matches observed phenomena in divers: variable sensitivity to decompression, acclimation to diving, the effect of elevated gas load on increased bubble formation, a higher bubble score in the second dive on the same day, and unexplained neurological symptoms after decompression. Large bubbles released from the arterial circulation give serious cause for concern.


Assuntos
Vasos Sanguíneos/fisiologia , Descompressão , Gases/sangue , Animais , Circulação Sanguínea , Descompressão/métodos , Oxigenoterapia Hiperbárica , Técnicas In Vitro , Estimulação Física/métodos , Fluxo Pulsátil/fisiologia , Ovinos , Estatísticas não Paramétricas
15.
Ann Vasc Surg ; 29(4): 650-3, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25752987

RESUMO

BACKGROUND: We present 7 cases of pulsatile tinnitus (PT) of venous origin in younger women seen over a period of 24 years and treated by Internal Jugular Bulb ligation. METHODS: All patients had a pulsatile bruit in one side of the neck that disappeared when gentle pressure over the internal jugular vein (IJV) caused it to collapse as seen in a duplex scan. Their computed tomography showed a dominant venous system with a high jugular bulb on the side of the bruit. RESULTS: The IJV was ligated under local anesthesia. Five patients in whom the ligation was done above the facial vein were cured. Two patients in whom the ligation was done below the facial vein experienced a decrease but not disappearance of the PT. CONCLUSIONS: Once other possible causes for PT have been discarded, ligation of the IJV above the facial vein cures this condition.


Assuntos
Veias Jugulares/cirurgia , Fluxo Pulsátil , Zumbido/cirurgia , Adulto , Fatores Etários , Anestesia Local , Feminino , Humanos , Veias Jugulares/diagnóstico por imagem , Veias Jugulares/fisiopatologia , Ligadura , Pessoa de Meia-Idade , Flebografia/métodos , Fluxo Sanguíneo Regional , Indução de Remissão , Estudos Retrospectivos , Fatores Sexuais , Fatores de Tempo , Zumbido/diagnóstico , Zumbido/fisiopatologia , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Ultrassonografia Doppler Dupla , Adulto Jovem
16.
Nutrients ; 6(12): 5992-6004, 2014 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-25533009

RESUMO

BACKGROUND AND AIMS: Atherosclerotic cardiovascular disease is the most common cause of mortality in patients with end-stage kidney disease. Chronic kidney disease patients often exhibit a deficiency in L-carnitine due to loss during hemodialysis (HD). We studied the effects of L-carnitine supplementation on brachial-ankle pulse wave velocity (baPWV), a marker of atherosclerosis, in HD patients. METHODS: This was a prospective, open-label, randomized, parallel controlled, multi-center trial testing the anti-atherosclerotic efficacy of oral L-carnitine administration (20 mg/kg/day). HD patients (n = 176, mean age, 67.2 ± 10.3 years old; mean duration of HD, 54 ± 51 months) with plasma free L-carnitine deficiency (<40 µmol/L) were randomly assigned to the oral L-carnitine group (n = 88) or control group (n = 88) and monitored during 12 months of treatment. RESULTS: There were no significant differences in baseline clinical variables between the L-carnitine and control groups. L-carnitine supplementation for 12 months significantly increased total, free, and acyl carnitine levels, and reduced the acyl/free carnitine ratio. The baPWV value decreased from 2085 ± 478 cm/s at baseline to 1972 ± 440 cm/s after six months (p < 0.05) to 1933 ± 363 cm/s after 12 months (p < 0.001) of L-carnitine administration, while no significant changes in baPWV were observed in the control group. Baseline baPWV was the only factor significantly correlated with the decrease in baPWV. CONCLUSIONS: L-carnitine supplementation significantly reduced baPWV in HD patients. L-carnitine may be a novel therapeutic strategy for preventing the progression of atherosclerotic cardiovascular disease.


Assuntos
Índice Tornozelo-Braço , Velocidade do Fluxo Sanguíneo/efeitos dos fármacos , Carnitina/farmacologia , Administração Oral , Idoso , Aterosclerose/mortalidade , Aterosclerose/prevenção & controle , Biomarcadores/sangue , Carnitina/análogos & derivados , Carnitina/sangue , Carnitina/deficiência , Suplementos Nutricionais , Feminino , Humanos , Falência Renal Crônica/complicações , Falência Renal Crônica/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fluxo Pulsátil , Diálise Renal/efeitos adversos
17.
Afr Health Sci ; 14(3): 743-52, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25352897

RESUMO

BACKGROUND: To design the pulse information which includes the parameter of pulse-position, pulse-number, pulse-shape and pulse-force acquisition and analysis system with function of dynamic recognition, and research the digitalization and visualization of some common cardiovascular mechanism of single pulse. METHODS: To use some flexible sensors to catch the radial artery pressure pulse wave and utilize the high frequency B mode ultrasound scanning technology to synchronously obtain the information of radial extension and axial movement, by the way of dynamic images, then the gathered information was analyzed and processed together with ECG. Finally, the pulse information acquisition and analysis system was established which has the features of visualization and dynamic recognition, and it was applied to serve for ten healthy adults. RESULTS: The new system overcome the disadvantage of one-dimensional pulse information acquisition and process method which was common used in current research area of pulse diagnosis in traditional Chinese Medicine, initiated a new way of pulse diagnosis which has the new features of dynamic recognition, two-dimensional information acquisition, multiplex signals combination and deep data mining. CONCLUSIONS: The newly developed system could translate the pulse signals into digital, visual and measurable motion information of vessel.


Assuntos
Medicina Tradicional Chinesa/métodos , Fluxo Pulsátil/fisiologia , Pulso Arterial , Artéria Radial/diagnóstico por imagem , Artéria Radial/fisiologia , Humanos , Ultrassonografia Doppler
18.
Eur J Endocrinol ; 170(1): 121-9, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24114435

RESUMO

OBJECTIVE: Estrogen stimulates pulsatile secretion of GH, via mechanisms that are largely unknown. An untested hypothesis is that estradiol (E2) drives GH secretion by amplifying interactions among GH-releasing hormone (GHRH), somatostatin (SS), and GH-releasing peptide (GHRP). DESIGN: The design comprised double-blind randomized prospective administration of transdermal E2 vs placebo to healthy postmenopausal women (n=24) followed by pulsatile GHRH or SS infusions for 13 h overnight with or without continuous GHRP2 stimulation. METHODS: End points were mean concentrations, deconvolved secretion, and approximate entropy (ApEn; a regularity measure) of GH. RESULTS: By generalized ANOVA models, it was observed that E2 vs placebo supplementation: i) augmented mean (13-h) GH concentrations (P=0.023), GHRH-induced pulsatile GH secretion over the first 3 h (P=0.0085) and pulsatile GH secretion over the next 10 h (P=0.054); ii) increased GHRP-modulated (P=0.022) and SS-modulated (P<0.001) GH ApEn; and iii) did not amplify GHRH/GHRP synergy during pulsatile GH secretion. By linear regression, E2 concentrations were found to be positively correlated with GH secretion during GHRP2 infusion (P=0.022), whereas BMI was found to be negatively correlated with GH secretion during GHRH (P=0.006) and combined GHRH/GHRP (P=0.015) stimulation. E2 and BMI jointly determined triple (combined l-arginine, GHRH, and GHRP2) stimulation of GH secretion after saline (R²=0.44 and P=0.003) and pulsatile GHRH (R²=0.39 and P=0.013) infusions. CONCLUSION: In summary, in postmenopausal women, E2 supplementation augments the amount (mass) and alters the pattern (regularity) of GH secretion via interactions among GHRH, SS, GHRP, and BMI. These outcomes introduce a more complex model of E2 supplementation in coordinating GH secretion in aging women.


Assuntos
Estradiol/uso terapêutico , Terapia de Reposição de Estrogênios , Hormônio Liberador de Hormônio do Crescimento/metabolismo , Hormônio do Crescimento Humano/metabolismo , Sobrepeso/metabolismo , Adeno-Hipófise/efeitos dos fármacos , Somatostatina/metabolismo , Idoso , Arginina/administração & dosagem , Índice de Massa Corporal , Método Duplo-Cego , Estradiol/administração & dosagem , Estradiol/efeitos adversos , Estradiol/farmacocinética , Terapia de Reposição de Estrogênios/efeitos adversos , Retroalimentação Fisiológica/efeitos dos fármacos , Feminino , Hormônio Liberador de Hormônio do Crescimento/administração & dosagem , Hormônio do Crescimento Humano/sangue , Humanos , Infusões Intravenosas , Pessoa de Meia-Idade , Oligopeptídeos/administração & dosagem , Oligopeptídeos/metabolismo , Sobrepeso/sangue , Sobrepeso/fisiopatologia , Adeno-Hipófise/metabolismo , Adeno-Hipófise/fisiopatologia , Pós-Menopausa , Fluxo Pulsátil/efeitos dos fármacos , Somatostatina/administração & dosagem , Adesivo Transdérmico
19.
J Hum Hypertens ; 28(5): 333-9, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24048291

RESUMO

There is limited evidence on the effect of potassium supplementation on the vasculature in patients at increased cardiovascular risk. Potassium increases aldosterone and there is a strong association of hyperaldosteronism with poor cardiac outcomes. We aimed to determine whether potassium supplementation has a significant medium-term effect on aldosterone levels and, if so, what the overall effect of this is on vascular function in patients at moderate cardiovascular disease risk. Forty patients at moderate cardiovascular disease risk were included in a randomised placebo-controlled crossover study. Patients were assigned to 64 mmol potassium chloride or placebo for 6 weeks. Vascular function was assessed using pulse-wave analysis including the detection of a change in augmentation index to salbutamol and nitroglycerine-induced vasodilation. There was no change in augmentation index with potassium vs placebo (25.2±1.4 vs. 26.0±1.3%, respectively). Potassium improved brachial systolic blood pressure (131.8±2.2 vs. 137.1±2.4 mm Hg; P=0.013), central systolic blood pressure (123.2±2.3 vs. 128.4±2.3 mm Hg; P=0.011) and central diastolic blood pressure (80.3±1.3 vs. 83.7±1.4 mm Hg; P=0.019). Plasma renin activity and serum aldosterone both increased with potassium (P=0.001 and P=0.048 respectively). We found that potassium supplementation had no effect on endothelial function or pulse-wave analysis. It lowered brachial systolic and central blood pressure. It was associated with increased plasma renin activity and serum aldosterone.


Assuntos
Pressão Sanguínea/efeitos dos fármacos , Hipertensão/tratamento farmacológico , Potássio na Dieta/administração & dosagem , Fluxo Pulsátil/efeitos dos fármacos , Sistema Renina-Angiotensina/efeitos dos fármacos , Adulto , Idoso , Aldosterona/sangue , Pressão Sanguínea/fisiologia , Estudos Cross-Over , Método Duplo-Cego , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/fisiologia , Feminino , Hemodinâmica/efeitos dos fármacos , Hemodinâmica/fisiologia , Humanos , Hipertensão/fisiopatologia , Masculino , Pessoa de Meia-Idade , Fluxo Pulsátil/fisiologia , Renina/sangue , Sistema Renina-Angiotensina/fisiologia , Medição de Risco , Sódio na Dieta/administração & dosagem
20.
J Tradit Chin Med ; 34(6): 673-7, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25618971

RESUMO

OBJECTIVE: To investigate a quantitative method for using radial artery pulse waveforms to assess the effect of pulsatile flow during cardiopulmonary bypass (CPB). METHODS: A total of 34 adults with heart disease who underwent open-heart surgery between April 2010 and January 2011 were randomized into a pulsatile perfusion group (n = 17) and a non-pulsatile perfusion group (n = 17). Radial arterial pulse waveforms of pulsatile and non-pulsatile perfusion patients were observed and compared before and during CDB. RESULTS: No pulse waveform could be detected at patients' radial artery in both groups when the aorta was cross-clamped. Pulse waveforms could be detected at pulsatile perfusion patients' radial artery, but could not be detected at non-pulsatile perfusion patients' radial artery during CPB. Additionally, patients' pulse waveforms during pulsatile perfusion were lower than those before the operation. CONCLUSION: Our findings indicate that radial artery sphygmogram can be used as a valid indicator to evaluate the effectiveness of pulsatile perfusion during CPB.


Assuntos
Cardiopatias/cirurgia , Fluxo Pulsátil , Artéria Radial/fisiopatologia , Adulto , Ponte Cardiopulmonar , Feminino , Cardiopatias/fisiopatologia , Frequência Cardíaca , Humanos , Masculino , Pessoa de Meia-Idade
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