[Relationship between inertial features of the upper extremity and simple reaction time in boys and girls aged 17-18].

The latent period of visual sensor-motor reaction depends, in part, on the sensory and integrative processes in the brain, but is also influenced by the rate of the muscle contraction. There is no clear evidence in the literature whether the rotational inertia of segments of limbs has any direct effect on the reaction time. The aim of our study was to identify this relationship. The study involved 566 right handed students aged 16-17 of both genders beginning their post puberty period. Reaction time was measured during experimental adduction of the forearm and hand, using a special rotating handle and lever connected to a computer that recorded the reaction time (+/- 1 ms). Calculations of the rotational inertia were carried out using regression models by Zatsiorsky and other authors. Each gender group was divided into three subgroups: with high, medium and low values of rotational inertia. It was found that individuals with high values of rotational inertia of forearm and wrist demonstrated significantly longer reaction times. This pattern was apparent in both gender groups. Although males illustrated greater values of rotational inertia than females they demonstrated relatively shorter reaction times. This contradiction can be explained by greater muscle power of young men. We recommend taking into account the amount of rotational inertia of the responsive segment in all kinds of research which require measurement of reaction time.

[Cardiac pathology and autonomic dysfunction in patients with vertebral and spinal cord injury].

The disturbances of cardiovascular function were examined in 103 patients with vertebral and spinal cord injury. To evaluate myocardial conduction time and regulation of heart rate we used the method of spiroarteriocardiorythmography. Comparative power spectral and time domain analyses of heart rate variability were carried out in patient and healthy individuals. The autonomic nervous system dysfunction revealed in patients result in severe cardiovascular complications and is associated with high risk of heart diseases.

[Information capability of the test with radioadaptive response in functiional evaluation of pilots].

Information capability of the radioadaptive response test was assessed during functional evaluation of pilots in the course of adaptation to fight factors. Functional evaluation was made on the system level, i.e., by cardiorespiratory parameters (spirometry and arteriorcardiography), the cellular level by individual sensitivity to ionized radiatiin of metabolic shifts (laser correlation spectroscopy of biological liquids). Changes in molecular composition of blood serum and cardiorespiratory functions were compared with individual radiosensitivity of pilots with varying fight time. Incidence of and strength of lymphocytes' RAR decreased with increasing flight hours. In light scattering spectra the input of particles with small hydrodynamic radius (no more than 11 nm) reduced and that of large particles (more than 200 nm) increased. Total power of the cardiac rhythm variability (CRV) spectrum decreased whereas stress-index grew in value. Breathing test raised peripheral systolic and diastolic blood pressure in masked pilots w/o RAR. Besides, it reduced total spectrum of systolic pressure variability and input of very low frequencies. In the group of RAR pilots, relative input of low frequencies into CRV grew and of high frequencies decreased; blood pressure did not alter Decreased input of small particles and increased input of large particles in light scattering as compared with baseline values were found only in RAR pilots suggesting shifts in metabolism and humoral immunity. It can be hypothesized that level of individual radiosensitivity reflects general resistance of organism to negative factors of environment.

[Anti-acetylcholine receptor antibodies: effect of immunosuppressive drug therapy in patients with myasthenia gravis].

We studied anti-acetylcholine receptor antibodies (ARAb) in 25 patients with myasthenia gravis before and after the immunosuppressive drug (steroid) therapy and in 22 patients before and after thymectomy. The clinical effect after the treatment was correlated with the reduction of ARAb levels by more than 20% in 62% of patients. The ARAb levels did not change, or even increased, in 15% patients despite the improvement of their clinical state. We showed the direct correlation between the clinical improvement and the decrease of ARAb level.

[Functional characteristics of cardiovascular system in adolescents with prehypertension].

Based on the results of sanogenetic monitoring the health of schoolchildren found that among high school students to the proportion of adolescents with elevated blood pressure (hypertension + hypernormotension) increases from 15-20% in 8th class to 30-50% in 9-11th classes, while the proportion of adolescents with hypertension was 3.7% in all age groups. Comparison of blood pressure with parameters of neurovegetative regulation of the cardiovascular system revealed that the presence of high normal blood pressure in 13-14-year-olds and 17-18-year-olds correlated with an increase in the proportion of low frequencies in the spectrum of HRV and lower values of the sensitivity of arterial baroreflex. At the age of 15-16 years, high-normal blood pressure accompanied by a decrease in heart rate, increase the sensitivity of arterial baroreflex and correlates with reduced power high-frequency part of the spectrum of HRV. When performing a functional test (an increase of "dead" breathing space) in hypernormotension teenagers 15-16 years, unlike normotensive peers, there is a reduction of finger blood pressure, and relative power of low frequencies in the spectrum of HRV, which may be associated with maladaptive functional changes in the sympathetic unit of autonomic regulation.

[Clinical features of myasthenia related with autoantibodies to muscle specific tyrosine kinase (MuSK)].

Anti-acetylcholine receptor antibodies are detected in 80 to 90% of patients with generalized myasthenia gravis - seropositive myasthenia gravis (SPMG). Approximately 10% to 20% of patients with autoimmune MG do not have antibodies to acetylcholine receptor (AChR) - seronegative MG (SNMG). An immunological study of the blood serum of patients with SNMG revealed patients with or without antibodies to muscle specific tyrosine kinase (MuSK+ and MuSK-, respectively). A clinical study of 13 MuSK+ patients with myasthenia showed that this group was characterized by predominant affect of mimic and bulbar muscles with the rare involvement of eye movement and body muscles. In Musk+ patients with myasthenia, the clinical efficacy of antitoxin esterase drugs was minimal or absent. No unequivocal conclusion on the clinical pattern of this form of myasthenia has been made.

[Use of laser correlation spectroscopy for evaluation of metabolic changes in workers engaged in radiation-dangerous industry].

The pattern of metabolic changes was studied in nuclear fuel plant workers by laser correlation spectroscopy (LCS) of biological fluids (blood serum and plasma, urine, oropharyngeal lavages (OPL). Plasma samples were divided into 3 groups: 1) control (unirradiated) samples; 2) those irradiated by below 100 mZv; 2) those irradiated by more than 100 mZv. With larger dose irradiation, the contribution of small particles (6-8 nm) to the dispersion of increased and the proportion of large components (300-400 nm) decreased. There was a correlation between the total accumulated dose, the dose in the past 9 months and the changes in the contribution of the above groups of particles to light diffusion. The found regulations in the changes of the subfraction composition of blood agree with earlier data on changes in the serum of nuclear fuel workers. Analysis of urine samples revealed an increase in the contribution of catabolic processes. That of OPL showed the preponderance of anabolic changes over catabolic ones in the presence of a considerable contribution of normologically similar LC spectra. Differences were found in the pattern of metabolic changes in relation to technological stages. Although the nature of the observed spectral transformations remains unknown, the simplicity and rapidity of the LCS technique may be considered as a suitable tool for detecting the effects caused by small dose irradiation and other factors.

[Use of a cytogenetic method for buccal epithelium study, and a method of laser correlation spectrometry for health disturbances monitoring in children].

Buccal epithelium cytogenetic disturbances were studied in schoolchildren from Moscow schools, a country school (Novgorod region) and a Moscow boarding school for chindren with musculoskeletal diseases (scoliosis and kyphosis). The minimal mean frequency of cells with karyorrhexis were revealed in children from an ecologically pure Novgorod region. Moscow schoolchildren demonstrated more than 13-fold higher level of this parameter. Children with spinal deformities had an intermediate frequency. Cells with karyolysis minimal mean frequency were observed in Moscow pupils. Children from Novgorod demonstrated a statistically valid higher level of this parameter, and the maximum was reached in Moscow boarding school. No difference between these groups was revealed in a study of the mean frequency of binucleated cells, cells with pyknosis, cells with micronuclei, or "broken eggs" incidence. Laser correlation spectrometry (LCS) method was used for parallel studies. It was shown that the distribution of spectra in Moscow pupils and in children with spinal deformities differs from that in children living in ecologically pure region. Normal spectra prevailed in pupils of country school, who demonstrated, in addition, high levels of anabolic and low levels of catabolic type metabolism. The examined Moscow schoolchildren demonstrated almost the same incidence of normal spectra. They differed from the country children by statistically valid reduction of anabolic type spectra, and by increased levels of catabolic type spectra. Young patients with spinal deformities demonstrated the maximum incidence of catabolic type spectra. The authors suggest the availability of a qualitative correlation between both the monitoring methods used in this study. It was shown that children living in unfavorable conditions and patients with musculoskeletal diseases manifested an enhanced incidence of buccal epithelium cells with karyorrhexis and karyolysis, as well as higher levels of catabolic type spectra accompanied by reduction of normal and anabolic type spectra.

[Lambert-Eatone myastenic syndrome].

A detailed comparative analysis of neurologic symptoms in 45 patients with Lambert-Eatone myastenic syndrome (LEMS) and 42 patients with generalized myasthenia allowed us to single out clinical patterns facilitating disease diagnosis and differentiation. There were no clinical differences in patients having LEMS with or without paraneoplastic process. Electromyography study revealed the presence of typical phenomena: a reduced amplitude of compound muscle action potential and incremental response at 40-Hz stimulation. The compound muscle action potential tripled after 20 s of maximal voluntary contraction. Sera from 89% of patients with LEMS contained IgG antibodies that immunoprecipitate a radiolabeled complex of a selective antagonist of P/Q type voltage-gated calcium channels. The degree of inhibition of calcium influx by patient's IgG correlated with the reduction in amplitude of the resting compound muscle action potential.

[Polysystemic assessment of the state of sanogenesis in workers employed in nuclear fuel plants. The analysis of metabolism regulation processes]. / Polisistemnaia otsenka sostoianiia sanogeneza rabotnikov predpriiatiia iaderno-toplivnogo tsikla.Analiz reguliatsii obmennykh protsessov.

Using the method of laser correlation spectroscopy of biological fluids (blood serum, urine, oropharyngeal washout fluid) we studied the types of metabolic shifts in workers employed in nuclear fuel complex plant. In was found that the incidence of catabolic shifts considerably increased in workers with higher level of occupational exposure. In individuals contacting with open radiation sources we found the contribution of anabolic immunomodifying shifts with predominance of autoimmune sensibilization. A risk group for blood diseases was identified.

[Polysystemic assessment of the state of sanogenesis in workers employed in nuclear fuel plants. The analysis of functional state of cardiovascular, respiratory, and psychomotor systems]. / Polisistemnaia otsenka sostoianiia sanogeneza rabotnikov predpriiatiia iaderno-toplivnogo tsikla.Analiz funktsional'nogo sostoianiia serdechno-sosudistoi, dykhatel'noi i psikhomotornoi sistem.

The state of the cardiovascular, respiratory, and psychomotor systems of workers employed in nuclear fuel plant was evaluated using a computer-assisted laboratory complex. It was found that neuroendocrine regulation of the peripheral circulation and muscular activity responsible for fine motions are most vulnerable to industrial hazardous factors.