[Monomelic amyotrophy]. / Monomelicheskaya amiotrofiya.

Monomelic amyotrophy, also known as Hirayama disease, is a rare neurological disorder characterized by focal and latent onset of upper limb weakness and atrophy in the absence of sensory deficits, bulbar or pyramidal signs. It usually occurs in young patients. The disease usually begins unnoticeably and progresses slowly, and can manifest itself as unilateral or asymmetrical weakness, as well as atrophy of the distal upper limb. Sensory disturbances, reflex changes and signs of lesions of lower motor neurons are rare. This article describes a case of a patient with complaints of weakness not only in the upper but also in the lower extremities.

Morphofunctional Changes in the Spinal Cord of Rats after Contusion Injury with Local Delivery of Methylprednisolone in Combination with a Copolymer.

We studied the neuroprotective effect of local application of methylprednisolone in combination with a block copolymer after contusion spinal cord injury in rats. Histological analysis of the spinal cord showed that delivery of a complex of methylprednisolone with a block copolymer reduced the volume of white and gray matter lesions. An increase in the amplitude of the evoked response of the gastrocnemius muscle was observed during epidural stimulation of the spinal cord 6 h after the injury. The maximum amplitude of the muscle response was greater in the group with local delivery of the methylprednisolone complex with the polymer 72 h after the injury. The obtained results demonstrate the neuroprotective effect of the local administration of the complex and allow to make positive prognosis for the recovery of the sensorimotor functions in rats.

The Effects of Repeated Administration of the Micellar Complex of Methylprednisolone on the Locomotor Activity of a Terrestrial Snails.

We studied the effects of repeated injections of methylprednisolone and its micellar complex with block-copolymer on locomotor activity of a terrestrial snail. It was shown that methylprednisolone solution injected into the hemolymph of the animal produced a direct effect on the muscle system of the animal as soon as 1 h after administration: it slowed down snail locomotion and reduced contractile activity of the foot muscles. The micellar complex of methylprednisolone with block-copolymer prevented this effect during the first 2 days of injection and negatively affected locomotion only in 2 days after injection, the decrease in locomotion in this case was not accompanied by a decrease in contractile activity of the foot muscle.

[Neuromotor apparatus in the condition of gravitational unloading: central and peripheral effects].

The functioning of central and peripheral structures of the gastrocnemius m. neuromotor apparatus was studied in rats exposed to simulated gravitational unloading. Gastrocnemius reflex (H) and motor (M) responses evoked by electrical stimulation of the sciatic nerve were measured after 7, 14, 21 and 35 days of tail-suspension. It was shown that thresholds of registered potentials went down on all days of testing; the H-amplitude rose during every testing and M-amplitude rose after 35 days of the gravitational unloading. Results of the experiments indicate changes in the functioning of motor centers that modulate properties and characteristics of peripheral neuromotor structures. The observed rearrangements can be caused by reduction of the afferent inflow.

[Effect of vibrostimulation of foot and supporting afferentation on functional state of shin muscles in rats during hindlimb unloading].

The goal of this work was to study the influence of daily 3-hr vibrostimulation of the supporting zones of the foot and 3-hr of usual locomotion on the functional state of the soleus, gastrocnemius, and tibial anterior muscles in rats after 7 and 14 days of hindlimb unloading. After 7 days of unloading the soleus weight decreased, while the weight of gastrocnemius and tibial anterior remained unchanged. After 14 days of hindlimb unloading a weight reduction was observed in all studied muscles. Vibrostimulation of the foot and supporting afferentation prevented the loss of weight in gastrocnemius and tibial anterior during the first week of unloading and reduced the negative effect of hindlimb unloading in 14 days. Our results demonstrate that the amplitude of the M-response after 7 days of hindlimb unloading was decreased predominantly in soleus as compared to gastrocnemius and tibial anterior. By the 14 day we observed restoration of the amplitude of the M-response in gastrocnemius and tibial anterior, and the increased amplitude of the M-response in soleus. Different techniques for foot stimulation in rats during hindlimb unloading demonstrated the positive effect in regard to M-response restoration--the amplitude of the M-response was increased in all studied muscles. Thus, our results demonstrate that foot vibrostimulation or supporting afferentation can completely prevent atrophy caused by hindlimb unloading in gastrocnemius and tibial anterior and decrease atrophy in soleus in rats.

[Effect of vibratory stimulation of foot support areas in rats on the functional state of leg muscles and the content of N2A titin isoforms in gravity relief].

In this work, we studied the effect of vibratory stimulation of the foot support zones on the functional state of the leg muscles and the content of N2A titin isoforms in rats under simulated microgravity (hanging model). The results of this study showed that vibratory support zones of the rat foot in a gravity discharge may reduce the incidence in amplitude of the leg muscle motor response and undesirable reduction of the titin content.