Search results for "reflex"
showing 10 items of 622 documents
Lack of genetic association of neutral endopeptidase (NEP) with complex regional pain syndrome (CRPS)
2010
Complex regional pain syndrome (CRPS) is a condition that is characterized by severe pain and exaggerated neurogenic inflammation, which may develop after injury or surgery. Neurogenic inflammation is mediated by neuropeptides, such as calcitonin gene-related peptide (CGRP) and substance P (SP) that are released from nociceptors. Genetic factors may play a role in CRPS as was suggested by the occurrence of familial cases and several genetic association studies investigating mainly the human leukocyte antigen (HLA) system. Here we investigated the role of neutral endopeptidase (NEP), a key enzyme in neuropeptide catabolism. NEP dysfunction resulting in reduced inactivation of neuropeptides m…
Cerebrovascular and cardiovascular variability interactions investigated through conditional joint transfer entropy in subjects prone to postural syn…
2017
Objective: A model-based conditional transfer entropy approach was exploited to quantify the information transfer in cerebrovascular (CBV) and cardiovascular (CV) systems in subjects prone to develop postural syncope. Approach: Spontaneous beat-to-beat variations of mean cerebral blood flow velocity (MCBFV) derived from a transcranial Doppler device, heart period (HP) derived from surface electrocardiogram, mean arterial pressure (MAP) and systolic arterial pressure (SAP) derived from finger plethysmographic arterial pressure device were monitored at rest in supine position (REST) and during 60° head-up tilt (TILT) in 13 individuals (age mean ± standard deviation: 28 ± 9 years, min-max r…
Masseter reflex and blink reflex abnormalities in Chiari II malformation.
2001
Masseter reflex and blink reflex were evaluated in 64 patients with a myelomeningocele and Chiari II malformation. In 46 patients, no brainstem signs or symptoms were present. Brainstem dysfunction related to Chiari II malformation occurred in 18 patients. The masseter reflex was more frequently abnormal in the symptomatic than asymptomatic patients (P = 0.02). Although the blink reflex was similarly affected in the two groups of patients (P > 0.1), it was very sensitive, being abnormal in 83% of symptomatic and 65% of asymptomatic patients. Concomitant abnormality of masseter reflex and the late contralateral blink reflex component (R2c) was almost exclusively found in symptomatic patients…
Isolated cranial nerve palsies in multiple sclerosis
1997
During a 10 year period 24 patients with definite multiple sclerosis with isolated cranial nerve palsies were studied (third and fourth nerve: one patient each, sixth nerve: 12 patients, seventh nerve: three patients, eighth nerve: seven patients), in whom cranial nerve palsies were the presenting sign in 14 and the only clinical sign of an exacerbation in 10 patients. MRI was carried out in 20 patients and substantiated corresponding brainstem lesions in seven patients (third nerve: one patient, sixth nerve: four patients, eighth nerve: two patients). Additional abnormal findings of electro-oculography, or masseter reflex, or blink reflex, or combinations of these were found in 20 patients…
Functional correlates of vertical gaze palsy and other ocular motor deficits in PSP: An FDG-PET study
2014
Abstract Objective To determine the functional correlates of vertical gaze palsy and other ocular motor deficits in patients with progressive supranuclear palsy (PSP) using [ 18 F]fluorodeoxyglucose (FDG-)PET. Methods Twenty-six patients with PSP underwent clinical examination of vertical gaze combined with FDG-PET scans to assess regional cerebral glucose metabolism as a marker of neuronal activity. Of these, eighteen PSP patients were also investigated by electrical nystagmography to determine horizontal ocular motor deficits. Statistical parametric mapping analyses were performed to correlate regional neuronal activity with ocular motor functions. Results In categorical comparisons, pati…
Differential Effects of Dry Eye Disorders on Metabolomic Profile by 1H Nuclear Magnetic Resonance Spectroscopy
2014
We used1H NMR spectroscopy to analyze the metabolomic profile of reflex tears from patients with dry eye disorders (DEDs). 90 subjects were divided into 2 groups: (1) patients with DEDs (DEDG;n = 55) and (2) healthy subjects (CG;n = 35). Additionally, the DEDG was subdivided into 2 subgroups based on DED severity: mild-to-moderate and moderate (n = 22andn = 33, resp.). Personal interviews and systematized ophthalmologic examinations were carried out. Reflex tears (20–30 μL) were collected by gently rubbing in the inferior meniscus of both eyelids with a microglass pipette and stored at −80°C until analysis. NMR spectra were acquired using a standard one-dimensional pulse sequence with water…
Electrophysiological brainstem testing in the diagnosis of reversible brainstem ischemia.
2002
The aim of this study was to evaluate the sensitivity of multimodal electrophysiological brainstem testing in the diagnosis of clinically suspected reversible ischemic deficits of the brainstem compared with diffusion weighted MR imaging. We investigated 158 consecutive patients presenting with signs of acute brainstem dysfunction. Serial electrophysiological brainstem tests including masseter reflex, blink reflex, masseter inhibitory reflex, AEP, MEP, EOG and the oculoauricular phenomenon were applied. In 14 of the 158 patients neurological deficits resolved in less than 24 hours, which was suggestive of a transitory ischemic attack (TIA), 19 patients had brainstem signs for more than 24 h…
Pontine lesions mimicking acute peripheral vestibulopathy
1999
OBJECTIVES Clinical signs of acute peripheral vestibulopathy (APV) were repeatedly reported with pontine lesions. The clinical relevance of such a mechanism is not known, as most studies were biased by patients with additional clinical signs of brainstem dysfunction. METHODS Masseter reflex (MassR), blink reflex (BlinkR), brainstem auditory evoked potentials (BAEPs), and DC electro-oculography (EOG) were tested in 232 consecutive patients with clinical signs of unilateral APV. RESULTS Forty five of the 232 patients (19.4%) had at least one electrophysiological abnormality suggesting pontine dysfunction mainly due to possible vertebrobasilar ischaemia (22 patients) and multiple sclerosis (ei…
Changes in muscle activity with increasing running speed.
2005
Electromyographic (EMG) activity of the leg muscles and the ground reaction forces were recorded in 17 elite male middle-distance runners, who performed isometric maximal voluntary contractions (MVC) as well as running at different speeds. Electromyograms were recorded from the gluteus maximus, vastus lateralis, biceps femoris, gastrocnemius and tibialis anterior. The results indicated that the averaged EMG (aEMG) activities of all the muscles studied increased (P < 0.05) with increasing running speed, especially in the pre-contact and braking phases. At higher speeds, the aEMG activities of the gastrocnemius, vastus lateralis, biceps femoris and gluteus maximus exceeded 100% MVC in these s…
Autonomic dysfunction in patients with achalasia.
1995
It has been previously shown that patients with achalasia may have motor abnormalities of the stomach, small bowel and biliary system. This study investigates whether a disturbance of extraintestinal autonomic function occurs. Autonomic function studies were performed in 15 patients with achalasia and 15 age- and sex-matched healthy controls. Pupillo-grams were obtained during darkness, light exposure and after pilocarpine administration. Cardiovascular function studies included determinations of heart rate variation during deep breathing and orthostasis. In addition, we determined blood pressure changes in response to sustained handgrip, cold exposure and orthostasis. Neurohormonal functio…