Brewers' spent grain (BSG) is a fibre and protein-rich by-product of beer-brewing. Fermenting BSG with can further increase its content of soluble fibre, protein and certain antioxidants. Since nutrients rich in BSG can improve postprandial glycaemic response, this study assessed the postprandial glucose response (PPGR) and postprandial insulin response (PPIR) controlling effect of consuming 30% wheat flour substituted biscuits with autoclaved BSG (ABSG) or fermented BSG (FBSG) in individuals with metabolic syndrome (MetS).
View Article and Find Full Text PDFScope: Okara is a fiber-rich food by-product whereby biovalorization with Rhizopus oligosporus can improve its nutritional quality, generating fermentable substrates for improved gut health maintenance. This study evaluates the impact of okara- and biovalorized okara-containing biscuits consumption on gut health in Singapore adults.
Methods And Results: Participants consume control (C), 20% flour-substituted okara (AOK), and 20% flour-substituted biovalorized okara (RO) biscuits for three weeks, with assessment of gut metabolites, microbiome, and dietary intake.
Asian representation in sport is increasing, yet there remains a lack of reference values for the Asian athlete's heart. Consequently, current guidelines for cardiovascular screening recommend using Caucasian athletes' norms to evaluate Asian athletes. This study aims to outline electrocardiographic and echocardiographic characteristics of the Asian athlete's heart using a Singaporean prospective registry of Southeast (SE) Asian athletes.
View Article and Find Full Text PDFSports-related sudden cardiac death is a rare but devastating consequence of sports participation. Certain pathologies underlying sports-related sudden cardiac death could have been picked up pre-participation and the affected athletes advised on appropriate preventive measures and/or suitability for training or competition. However, mass screening efforts - especially in healthy young populations - are fraught with challenges, most notably the need to balance scarce medical resources and sustainability of such screening programmes, in healthcare systems that are already stretched.
View Article and Find Full Text PDFBackground And Objectives: Few studies have been published that evaluate the usefulness of different caries- diagnostic modalities in general dental practice. The goal of this study was to compare the results of screening for coronal dental caries in a general dental practice using clinical observations, radiographs, laser fluorescence (DIAGNOdent™) (LF), and optical coherence tomography (OCT). Diagnostic agreement between OCT and LF versus standard clinical techniques for detecting caries was determined in 40 subjects.
View Article and Find Full Text PDFUndersea Hyperb Med
March 2014
Objective: This study examined whether military diving during a National Serviceman's two-year term of service affected his hearing threshold levels.
Methods: A retrospective cohort study was designed to examine the hearing thresholds of divers (mean age 20.9 years) who enlisted between 2001 and 2010 (n = 748).
A lumped parameter model of the cardiovascular system has been developed and optimized using experimental data obtained from 13 healthy subjects during graded head-up tilt (HUT) from the supine position to [Formula: see text]. The model includes descriptions of the left and right heart, direct ventricular interaction through the septum and pericardium, the systemic and pulmonary circulations, nonlinear pressure volume relationship of the lower body compartment, arterial and cardiopulmonary baroreceptors, as well as autoregulatory mechanisms. A number of important features, including the separate effects of arterial and cardiopulmonary baroreflexes, and autoregulation in the lower body, as well as diastolic ventricular interaction through the pericardium have been included and tested for their significance.
View Article and Find Full Text PDFAnnu Int Conf IEEE Eng Med Biol Soc
August 2015
This study investigated whether arterial blood pressure waveform analysis could be useful for estimating left ventricular outflow (LVO) and total peripheral resistance (TPR) in preterm infants. A cohort of 27 infants were studied, with 89 measurements of left ventricular outflow (LVO) using Doppler echocardiography and arterial pressure using catheters, performed in 0, 12, 24 and 36 hours after birth. TPR was computed as mean arterial pressure divided by LVO.
View Article and Find Full Text PDFVery preterm infants are at high risk of death and serious permanent brain damage, as occurs with intraventricular hemorrhage (IVH). Detrended fluctuation analysis (DFA) that quantifies the fractal correlation properties of physiological signals has been proposed as a potential method for clinical risk assessment. This study examined whether DFA of the arterial blood pressure (ABP) signal could derive markers for the identification of preterm infants who developed IVH.
View Article and Find Full Text PDFBackground: Cardiac output (CO) and systemic vascular resistance (SVR) are two important parameters of the cardiovascular system. The ability to measure these parameters continuously and noninvasively may assist in diagnosing and monitoring patients with suspected cardiovascular diseases, or other critical illnesses. In this study, a method is proposed to estimate both the CO and SVR of a heterogeneous cohort of intensive care unit patients (N=48).
View Article and Find Full Text PDFAnnu Int Conf IEEE Eng Med Biol Soc
June 2012
The concept of early goal-directed therapy emphasizes the need for early diagnosis and intervention to achieve better therapeutic outcomes in critical care. There has been rapidly growing interest in the use of the photoplethysmogram (PPG), also known as the "pulse oximetry waveform", as a noninvasive diagnostic tool in this clinical setting. The peripheral PPG exhibits beat-to-beat variability driven by physiological mechanisms such as respiration and sympathetic vascular activity.
View Article and Find Full Text PDFAnnu Int Conf IEEE Eng Med Biol Soc
June 2012
Near-infrared spectroscopy (NIRS) for cerebral circulation monitoring has gained popularity in the neonatal intensive care setting, with studies showing the possibility of identifying preterm infants with intraventricular hemorrhage (IVH) by transfer function analysis of arterial blood pressure (BP) and NIRS measures. In this study, we examined a number of NIRS-derived measures in a cohort of preterm infants with IVH (n = 5) and without IVH (n = 12) within 1-3 hours after birth. The IVH infants were found to have significantly higher tissue oxygenation index (TOI), lower fractional tissue oxygen extraction (FTOE) and lower coherence between arterial BP and deoxygenated hemoglobin (HHb) in the very low frequency range (VLF, 0.
View Article and Find Full Text PDFThe human body possesses a unique set of organs that are responsible for providing homeostatic balance to the body's fluids. Of these, the kidneys regulate fluid and electrolyte balance in order to maintain the intracellular and extracellular fluid volumes and ion composition within tight limits. When kidneys fail to function normally, fluid is retained and several ions and solutes accumulate.
View Article and Find Full Text PDFAssessment of spontaneous slow waves in the peripheral blood volume using the photoplethysmogram (PPG) has shown potential clinical value, but the physiological correlates of these fluctuations have not been fully elucidated. This study addressed the contribution of arterial pressure and muscle sympathetic nerve activity (MSNA) in beat-to-beat PPG variability in resting humans under spontaneous breathing conditions. Peripheral PPG waveforms were measured from the fingertip, earlobe, and toe in young and healthy individuals (n = 13), together with the arterial pressure waveform, electrocardiogram, respiration, and direct measurement of MSNA by microneurography.
View Article and Find Full Text PDFFrequency spectrum analysis of circulatory signals has been proposed as a potential method for clinical risk assessment of preterm infants by previous studies. In this study, we examined the relationships between various spectral measures derived from systemic and cerebral cardiovascular variabilities and the clinical risk index for babies (CRIB II). Physiological data collected from 17 early low birth weight infants within 1-3 h after birth were analysed.
View Article and Find Full Text PDFBiological signals often exhibit self-similar or fractal scaling characteristics which may reflect intrinsic adaptability to their underlying physiological system. This study analysed fractal dynamics of cerebral blood flow in patients supported with ventricular assist devices (VAD) to ascertain if sustained modifications of blood pressure waveform affect cerebral blood flow fractality. Simultaneous recordings of arterial blood pressure and cerebral blood flow velocity using transcranial Doppler were obtained from five cardiogenic shock patients supported by VAD, five matched control patients and five healthy subjects.
View Article and Find Full Text PDFThere is a need for robust techniques for early and accurate diagnosis of acute coronary syndromes (ACSs), to avoid inappropriate discharge of patients. This study examined the use of frequency spectrum analysis of heart rate variability (HRV) and photoplethysmogram (PPG) waveform variability for the identification of high-risk ACS patients defined by an elevated cardiac troponin level. The study cohort comprised a convenience sample of adult patients presenting to the emergency department of the Prince of Wales Hospital over a 4 month period complaining of non-traumatic chest pain.
View Article and Find Full Text PDFSystemic vascular resistance (SVR) classification is useful for the diagnosis and prognosis of critical pathophysiological conditions, with the ability to identify patients with abnormally high or low SVR of immense clinical value. In this study, a supervised classifier, based on Bayes' rule, is employed to classify a heterogeneous group of intensive care unit patients (N = 48) as being below (SVR < 900 dyn s cm(-5)), within (900 ⩽ SVR ⩽ 1200 dyn s cm(-5)) or above (SVR > 1200 dyn s cm(-5)) the clinically accepted range for normal SVR. Features derived from the finger photoplethysmogram (PPG) waveform and other routine cardiovascular measurements (heart rate and mean arterial pressure) were used as inputs to the classifier.
View Article and Find Full Text PDFThe fundamental determinants of human dynamic cerebral autoregulation are poorly understood, particularly the role of vascular compliance and the myogenic response. We sought to 1) determine whether capacitive blood flow associated with vascular compliance and driven by the rate of change in mean arterial blood pressure (dMAP/dt) is an important determinant of middle cerebral artery velocity (MCAv) dynamics and 2) characterise the impact of myogenic blockade on these cerebral pressure-flow velocity relations in humans. We measured MCAv and mean arterial pressure (MAP) during oscillatory lower body negative pressure (n =8) at 0.
View Article and Find Full Text PDFBackground: The insertion of Ventricular Assist Devices is a common strategy for cardiovascular support in patients with refractory cardiogenic shock. This study sought to determine the impact of ventricular assist devices on the dynamic relationship between arterial blood pressure and cerebral blood flow velocity.
Methods: A sample of 5 patients supported with a pulsatile ventricular assist device was compared with 5 control patients.
Low frequency variability in the fingertip photoplethysmogram (PPG) waveform has been utilized for inferring sympathetic vascular control, but its relationship with a quantitative measure of vascular tone has not been established. In this study, we examined the association between fingertip PPG waveform variability (PPGV) and systemic vascular resistance (SVR) obtained from thermodilution cardiac output (CO) and intra-arterial pressure measurements in 48 post cardiac surgery intensive care unit patients. Among the hemodynamic measurements, both CO (P < 0.
View Article and Find Full Text PDFThis paper proposes a novel model-based control methodology for a computer-controlled hemodialysis system, designed to maintain the hemodynamic stability of end-stage renal failure patients undergoing fluid removal during hemodialysis. The first objective of this paper is to introduce a linear parameter varying system to model the hemodynamic response of patients during hemodialysis. Ultrafiltration rate (UFR) and dialysate sodium concentration (DSC) are imposed as the inputs, and the model computes the relative blood volume (RBV), percentage change in heart rate ( ∆HR), and systolic blood pressure (SBP) during the course of hemodialysis.
View Article and Find Full Text PDFThe Windkessel properties of the vasculature are known to play a significant role in buffering arterial pulsations, but their potential importance in dampening low-frequency fluctuations in cerebral blood flow has not been clearly examined. In this study, we quantitatively assessed the contribution of arterial Windkessel (peripheral compliance and resistance) in the dynamic cerebral blood flow response to relatively large and acute changes in blood pressure. Middle cerebral artery flow velocity (MCA(V); transcranial Doppler) and arterial blood pressure were recorded from 14 healthy subjects.
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