Eletrophysiology

To investigate the eletrophysiological effect of rat adrenomedullin (rADM) on barosensitive neurons in the rostral ventrolateral medulla (rVLM) and its potential mechanisms, the extracellular recording and multi-barrel iontophoresis methods were used. Of the 29 barosensitive neurons in the rVLM, 20 neurons demonstrated excitatory response to iontophoretically applied rADM and increased the firing rate from (10.8 +/- 2.7) spikes/s to (14.6 +/- 3.6), (19.8 +/- 4.7) and (31.9 +/- 6.4) spikes/s (P<0.05, n=20) at the current of 30, 60 and 90 nA, respectively...

Pure neural leprosy (PNL) is difficult to diagnose because skin lesions and acid-fast bacilli (AFB) in slit smears are absent. At present, the gold standard for PNL diagnosis is the histopathological examination of a peripheral nerve biopsy. Even so, detection of bacteria is difficult and histological findings may be non-specific. Furthermore, nerve biopsy is an invasive procedure that is only possible in specialized centres. Therefore, there is a need for additional diagnostic methods that may help to confirm the clinical diagnosis of PNL...

The authors review the literature on the epidemiology, the clinical and electrophysiological symptoms of somnambulism. The disorder specified as "nREM parasomnia with awakening disorder" belongs to the nREM sleep (awakening) parasomnias. In most of the cases its occurence is familial with the highest prevalence at age 12 year. Above age 12 year most cases recover whereas 6% of prevalence is reported in adults. It is probable that most patients seek medical help only in severe cases associated with injuries, accidents or violence...

One aim of integrative neurophysiology is to understand the relationship between neuronal activity and normal evolution of other physiological parameters. In this respect, anaesthetics or paralyzing agents, that have been shown to have a significant effect on several vital physiological processes, can be seen as a real problem for the interpretation of observations. Eletrophysiological recording in awake animals avoids this problem. Recordings in forebrain areas are now used routinely but a number of specific difficulties have limited their application to the medullary areas...

In this experiment anhydrous glycerol was injected into the mental foramen of rabbits to determine neurolytic effects on the peripheral trigeminal nerve by electrohysiologic and morphologic methods.The rabbits underwent unilateral injection of anhydrous glycerol and the control side was injected with normal saline.The results show that partial fibers are effected (myelinated and unmyelinated fibers at random).Glycerol injection increased the average latencies and reduced the average amplitudes of compound action potentials...

Anterior cingulate cortex (ACC), an important part of the limbic system, has extensive connections with other cortical areas and subcortical nuclei and is involved in modulating many functions. In recent years, an increasing body of evidence in eletrophysiology, functional imaging and behavioral study indicates that ACC is closely involved in processing of pain, especially in the affective dimension of pain. This review will focus on the progress in the study of ACC in processing of pain.

INTRODUCTION: Certain features of event-related potentials (ERPs), electroencephalographic (EEG), and behavioural measures vary with differing states of alertness and/or sedation. PURPOSE: This study was conducted to investigate changes in several measures usually viewed as reflecting states of sedation/sleepiness associated with the use of a range of doses of the hypnotic benzodiazepine (BZD) flunitrazepam (FNZ). METHODS: This was a double blind, independent group design study of the effects of acute oral doses of FNZ in young healthy volunteers...

OBJECTIVE: To explore the effects of exogenous nerve growth factor (NGF) in the regeneration of adult white rabbit inferior alveolar nerves within silicone tubes. METHODS: Twenty-four adult white rabbits were selected. Bilateral 8 mm inferior alveolar nerve gaps were created, and the proximal and distal stumps were inserted into a 12 mm silicone tube. The right side silicone tube was filled with exogenous NGF (experimental group) and the contralateral side was filled with saline (control group)...

Chédiak-Higashi syndrome is a rare hematological disease characterized by increased fusion of cytoplasmatic granules. Neurological symptoms occur in approximately half of the patients. We describe the clinical, eletrophysiological, hematological and radiological findings in a girl who had Chédiak-Higashi syndrome and seizures.

OBJECTIVE: To evaluate and compare in a double-blinded and prospective study the incidence of adverse reactions between two contrast agents used for coronary angiography and ventriculography. The first agent was the non-ionic, dimeric, isotonic contrast medium iodixanol (Visipaque), the other was the ionic dimeric contrast medium ioxaglate (Hexabrix). METHODS: A total of 110 consecutive patients were randomized and received either iodixanol 320 mgl/ml or ioxaglate 320 mgl/ml...

Clostridium difficile has been pointed out as an important agent of diarrheal diseases associated with antibiotic use. However, due to its complexity, the physiopathology of these diseases is only partially elucidated, although a series of scientific works has demonstrated the importance of toxins A and B in the pathogenesis of the inflammatory diarrhea induced by this microorganism. The inflammatory mechanisms involved in the biological activities of these toxins are complex. There are some studies demonstrating that toxin B has no enterotoxic activity in vivo...

Soman (pinacolymethylphosphonofluoridate), a highly potent, irreversible inhibitor of cholinesterase, causes intense convulsions, neuropathology and, ultimately, death. There is evidence that certain brain structures are selectively vulnerable to the pathological consequences of soman-induced seizures. A working hypothesis is that central nervous system (CNS) structures with the earliest and most severe signs of neuropathology may be key sites for the initiation of the seizures. Fos, the immediate-early gene product, increases rapidly in several animal seizure models...

Electrophysiologic findings suggesting the coexistence of dual atrioventricular (AV) nodal pathways and accessory AV connections have been previously described. Anterograde conduction through the accessory pathway (AP) may preclude the diagnosis of AV nodal dual pathway physiology during atrial stimulation. This study reports on a patient with manifest Wolff-Parkinson-White syndrome with clinically documented paroxysmal atrial fibrillation, in whom dual AV nodal pathways were unmasked after successful radiofrequency ablation of two accessory AV connections...

No abstract text is available yet for this article.

No abstract text is available yet for this article.

Tuberous sclerosis is a neurologic disease affecting various organs with a triade: sebaceum adenoma, mental retardation and seizures. This report presents a case of a patient with tuberous sclerosis and third degree A-V block with complete invasive and non-invasive evaluation. The patient had sincope and complete A-V block with QRS complexes showing right bundle branch block morphology. The echocardiogram showed dilated cardiomyopathy with diffuse left ventricular dysfunction and had normal coronary arteriography...

Beta-2 adrenergic receptors were found in a human heart and their role in regulation of inotropic properties during last year was proved. The aim of our study was comparison of effects of selective (metoprolol) and nonselective (propranolol) beta-receptors blockade on cardiac electrophysiological properties. The study was carried out in 20 patients in the majority without organic heart injury and clinical symptoms of the sinus node dysfunction as well as atroioventricular conduction disorders. Method of the transoesophageal left atrial stimulation was utilized...

In an effort to investigate the possibility of noncholinergic nicotine sites within the brain, psychopharmacological, biochemical and eletrophysiological studies were undertaken with nicotine and various newly synthesized derivatives of nicotine and piperidine. When 1-10 micrograms of (-)-nicotine was injected into the region of the lateral ventricle of rats through implanted cannulae, there resulted a characteristic prostration immobilization syndrome, which was accompanied by seizures and tremors at the higher dose range...

Passive transfer of experimental autoimmune myasthenia gravis (EAMG) was achieved using the gamma globulin fraction and purified IgG from sera of rats immunized with Electrophus electricus (eel) acetylcholine receptor (AChR). This demonstrates the critical role of anti-AChR antibodies in impairing neuromuscular transmission in EAMG. Passive transfer of anti-AChR antibodies from rats with chronic EAMG induced signs of the acute phase of EAMG in normal recipient rats, including invasion of the motor end-plate region by mononuclear inflammatory cells...