Projects / Programmes
Fiziološki mehanizmi nevroloških bolezni (Slovene)
| Code |
Science |
Field |
Subfield |
| 3.03.00 |
Medical sciences |
Neurobiology |
|
| Code |
Science |
Field |
| B640 |
Biomedical sciences |
Neurology, neuropsychology, neurophysiology |
| B560 |
Biomedical sciences |
Urology, nephrology |
Single fibre electromyography, axonal microstimulation, neuromuscular transmission, safety factor, neuromuscular junction disorders, uroneurophysiology, uroneurology, sacral nervous system, bulbocavernosus reflex, anal sphincter, electromyography, pudendal SEP, enuresis, transcranial stimulation, motor cortex, corticobulbar tract jitter, single motor unit, Charcot-Marie-Tooth disease type 1, CMT1A duplication, hereditary neuropathy with liability to pressure palsies, HNPP deletion, Thr118Met PMP22 amino acid substitution
Researchers (38)
Organisations (1)
Abstract
In the first part of the project, microelectrophysiology of muscle with stimulation single fibre EMG, we investigated the effect of neural activity upon the level of mRNA for acetylcholinesterase. Aboundant fibrillation in the regenerating muscle maintained this level at 80% of the control value. Single fibre EMG was used for semiquantitative estimation of spontaneous activity in denervated muscle fibres and in the fibrillating myotubes. A method for diagnostic assessment of the neuromuscular jitter in the frontalis muscle was developed. The relationship between the jitter at individual neuromuscular junctions and their safety factor was studied.
In the second part of the project, uroneurophysiology in the studies of the sacral nervous system lesions, we developed and applied modified clinical neurophysiological methods for assessment of patients with involvement of the sacral neuromuscular system and sacral dysfunctions (lower urinary tract, anorectal, sexual dysfunctions). We have further developed mechanical stimulation to elicit sacral reflexes and cerebral somatosensory evoked potentials in children and have performed several studies to standardise anal sphincter EMG. Among the patients groups studied were boys with enuresis, women with incontinence after vaginal deliveries, and patients with conus and cauda equina lesions. The uroneurophysiological methods developed serve as a clinically useful tool in assessment of lesions in the sacral neuromuscular system. Apart from the use in diagnosis, recording of the bulbocavernosus reflex has proved to be a potentially useful intraoperative monitoring method in patients in whom the sacral nervous system is at risk during surgical procedures.
The third part of the project comprises studies on physiological mechanisms of noninvasive electrical and magnetic brain stimulation in man. We examined the corticobulbar influence on the facial muscle motoneurons by studying single motor unit responses. The peristimulus time histogram technique and latency variability of single motor unit responses were used to obtain evidences of monosynaptic cortical projections to the facial motoneurons. The synaptic transmission efficiency at this site was, in comparison to the spinal level, of the same magnitude. In a similar study we found that the facial muscle responses after magntic brain stimulation may at list partially be due also to their reflex activation. The stimulating round coil namely covers a large area of the skull and can concurrently stimulate the motor cortex and the trigeminal nerve sensory afferents which in turn trigger the blink reflex.
In the fourth part of the project, molecular genetic studies of the demyelinative type of hereditary motor and sensory polyneuropathy, it was determined that the dominantly inherited CMT1A duplications and HNPP deletions on chromosome 17p11.2 are, as in most other European countries, the most common mutations also in Slovene patients. No signs of polymorphism or potentially recessive mutation were found at the specific Thr118Met PMP22 site.
