Brain imaging based on functional MRI (fMRI) provides a powerful tool for characterizing age-related changes in functional anatomy. However, between-population comparisons confront potential differences in measurement properties. The present experiment explores the feasibility of conducting fMRI studies in nondemented and demented older adults by measuring hemodynamic response properties in an ...

INTRODUCTION The purpose of our study was to determine whether hypothermia has any effects on physiological hemodynamic responses to epinephrine (Epi), and whether rewarming reverses these effects. METHODS Sprague-Dawley rats were instrumented to measure mean arterial pressure (MAP), and left ventricular (LV) pressure-volume changes were recorded by using a Millar pressure-volume conductance ...

Hu D, Huang L. Negative hemodynamic response in the cortex: evidence opposing neuronal deactivation revealed via optical imaging and electrophysiological recording. J Neurophysiol 114: 2152–2161, 2015. First published July 15, 2015; doi:10.1152/jn.00246.2015.— Functional brain imaging techniques depend on the relationship between regional hemodynamic responses and neural activity. The positive ...

Opioids are well known to cause cardiovascular depression. The aim of the present investigation was to determine whether an interaction of opioid derivatives with catecholamines might be involved in these hemodynamic alterations. Six comatose patients were enrolled into a prospective, nonrandomized pilot trial. All patients first received a continuous i.v. infusion of dobutamine (10 microgram. ...

OBJECTIVES To evaluate the hemodynamic responses to nociceptive stimuli in children submitted to videolaparoscopic appendectomy under balanced anesthesia with isoflurane and dexmedetomidine. METHODS Randomized, double-blind and placebo-controlled study involving 26 children submitted to videolaparoscopic appendectomy carried out at Hospital São Lucas (PUCRS) between May 2004 and February 2005...

In the present multiple case study, we examined hemodynamic changes in the brain in response to motor execution (ME) and motor imagery (MI) of swallowing in dysphagia patients compared to healthy matched controls using near-infrared spectroscopy (NIRS). Two stroke patients with cerebral lesions in the right hemisphere, two stroke patients with lesions in the brainstem, and two neurologically he...

background: to determine whether islamic fasting would change cerebral blood flow during ramadan. methods: the study group comprised 20 subjects (16 males and 4 females) on a regimen of 1 month food and water intake restriction, according to islamic fasting ritual. subjects were evaluated for cerebral bolo flow through a middle cerebral artery (mca) by means of transcranial doppler (tcd), the d...

objective(s):the present study investigated the effect of long-term mild cerebral hypoperfusion induced by permanent unilateral (right) common carotid artery occlusion (uco) on the dorsal hippocampal neurons in rats. materials and methods:sixty four male sprague-dawley rats aged 4 months were divided into two groups of sham and uco. these two groups were further divided into 4 sets of histopath...

Introduction The important role of fMRI in geriatrics is to assess the change of brain activation related to early signs of cognitive impairments. Various cognitive tasks increased the activation in the frontal or parietal areas in elderly subjects. On the other hand, age-related reduction of BOLD signal in the primary visual area (V1) has been discussed [1 3]. In this study, we investigated th...

The mechanism of resting or nocturnal angina relative to primary alterations in myocardial oxygen supply or demand (MVO2) is still uncertain. We studied 23 patients (15 males, eight females, ages 45-83 years) with coronary artery disease (CAD) and rest angina using electrocardiographic and hemodynamic monitoring by intra-arterial line and Swan-Ganz thermodilution catheter. Data were recorded co...