Evaluation of changes in the cortical gait control in post-stroke patients induced by the use of the “Regent” soft exoskeleton complex (SEC) by navigated transcranial magnetic stimulation

The mechanisms underlying the locomotion recovery in poststroke patients remain unknown. Navigated transcranial magnetic stimulation (nTMS) is a new method to evaluate the functional state of the motor system. Using of the “Regent” soft exoskeleton complex (SEC) allow to correct walking pattern significantly. The aim of this study was to evaluate the capability of nTMS to assess changes in gait cortical control using SEC in poststroke patients. 14 patients of the subcortical stroke (the mean age was 53.0 years, the mean time from stroke onset was 14.2 months) received 10 training sessions with SEC. The patients received nTMS before and after the sessions, as well as they were clinically evaluated by the Fugl–Meyer scale section for lower extremity and a 10-m walk test. Whereas a reliable reduction in the time of walking for 10 m was recorded after the sessions with the application of SEC, the Fugl-Meyer scale assessment remained unchanged. During nTMS, a reduction was recorded in the average latency of evoked motor response from the affected hemisphere, as well as various patterns of changes in the size and localization of cortical representations of the leg muscles. We have concluded that the nTMS method allowed us to identify the individual patterns of changes in the cortical representations of leg muscles as a result of the use of SEC in post-stroke patients with injuries in a group of locomotor system elements, thus identifying not only the fact of the undergoing neuroplastic processes, but also their direction.     

Lysozymes in insects: what role do they play in nitrogen metabolism?

Abstract. Lysozymes are widely distributed in many organisms as one of the components of defence mechanisms. In herbivores, when nitrogen is not contained in sufficient amounts in the diet, bacteria lysed by stomach lysozymes are used as sources of nitrogen. In ruminants, lysozymes function as digestive enzymes in the true stomach. A convergence of amino acid sequence has been shown between the stomach lysozymes of different ruminants, and similar lysozymes have recently been reported in the gut or salivary gland of insects. In this mini review, the enzymatic and ecological functions of lysozymes in insects, particularly in termites, are introduced, together with future studies that are needed in this field.     

Characteristics of DNA synthesis in Chinese hamster cells in exponential and stationary culture growth stages after cell exposure to elevated temperature

Hyperthermia (43 degrees C for 1 hour) is shown to induce a reduction of DNA synthesis and a change in molecular weight distributions in the pool of newly synthesized DNA in cultured Chinese hamster cells. The DNA synthesis inhibition extent as well as the character of disturbances in DNA replication are different in cells of the exponential and the stationary cultures.     

Polyanions inhibit the binding of autoantibodies with some cellular proteins

Effect of polyanions on reaction of the Ig from sera of patients with systemic lupus erythematosus and scleroderma with cellular proteins was studied by immunoblotting. It has been shown that dextran sulfate, heparin, denatured DNA and poly I inhibited the binding of autoantibodies with some polypeptides. The molecular weight of these antigens was determined. The molecular mechanism of immunological reactions studied and it's role in pathogenesis of autoimmune diseases is discussed.     

A radiometric method for developing the alkaline sucrose gradient sedimentation patterns of DNA from nondividing cells.

A radiometric method for developing the alkaline sucrose gradient sedimentation patterns of DNA from nonlabeled cells is described. The principle of the method is the labeling of the DNA contained in the gradient fractions by means of the binding of a labeled amino acid to DNA in the presence of formaldehyde. The procedure involves incubation of the fractions with the labeling reagent, filtration of the incubation mixtures through nitrocellulose filters, and radiometry of the filters. The relationship between the radioactivity on the filters and the DNA concentration in the sample is linear; the DNA detection sensitivity is sufficient to escape overloading of the gradients. It was shown that the nonlabeled mammalian cell DNA sedimentation patterns developed by the method described and those of DNA from the same cells labeled with [³H]thymidine in vivo are identical.     

The effects of support deprivation and stimulation of the foot support zones on the lateral stiffness and electromyogram of the resting calf muscles

The lateral stiffness and electromyogram characteristics of the resting calf flexor and extensor muscles have been studied in 18 subjects during a seven-day immersion with and without mechanical stimulation of the foot support zones. It has been shown that as early as day 1 of support deprivation, the lateral stiffness steadily decreases in the m. soleus and, in contrast, drastically increases in the m. tibialis anterior. A mechanical stimulation of the foot support zones decreases the rate and degree of the changes observed in both muscles. The tight correlation of the changes in the lateral stiffness with the muscle activity suggests a significant dependence of these changes on the electromyogram characteristics at rest.     

Studies of complex lipids. Synthesis of ionophore derivatives of diphosphatidylglycerol (cardiolipin)

Synthesis of cardiolipin analogues containing an ionophore residue in the fatty acid moiety is described. The ionophore, dibenzo-18-crown-6, has been incorporated into second position of the glycerol residue by acylating mono- and dilysocardiolipin with a modified fatty acid anhydride. Lyso-derivatives of cardiolipin have been prepared by enzymatic hydrolysis of beef heart cardiolipin by snake venom phospholipase A2 (Naja naja oxiana).     

Gamma-irradiation induces in HeLa cells radioresistant DNA synthesis

Cells of a suspension HeLa culture at the logarithmic phase of growth were exposed to 60Co-gamma-rays (5 Gy), incubated in the nutritious medium, and in 4 h subjected to repeated irradiation: the dose-response function and the dynamics of DNA synthesis inhibition were determined. It was shown that DNA synthesis was inhibited to a lesser extent after preirradiation, in other words, DNA synthesis was radioresistant. A correlation between this synthesis and reproductive cell death is discussed.     

基于改进三维生态足迹模型的洞庭湖区生态可持续时空演化研究

洞庭湖是长江流域重要的调蓄湖泊，也是中国重要的农产品主产区。科学评估洞庭湖区生态可持续状态，揭示其时空演化特征，对探究其生态可持续影响因素与作用机理，降低生态赤字具有重要意义。基于碳足迹与生态足迹理论构建了改进的三维生态足迹模型，填补了化石能源无法核算生态承载力的问题，同时调整了不同土地利用类型的参数因子。在对洞庭湖区25个区县进行可持续发展的动态评价分析中，计算了2000—2019年生态赤字、足迹广度与深度的时空分布特征。研究结果表明：(1)近20年来洞庭湖区的人均生态足迹增长速度远高于人均生态承载力，致使人均生态赤字在时间维度上不断增大，空间维度上呈湖滨向周边地区扩散的趋势；(2)洞庭湖区除林地之外的土地利用类型均存在自然资本存量的消耗，且表现为高生态赤字；(3)三次产业结构的分配、土地利用的变化、居民对生活质量的提高以及生态保护政策的有效实施等均会对洞庭湖区的可持续发展产生较大影响；(4)改进后的化石能源账户相较于传统账户的计算方法更能反映真实的碳排量与碳吸收量。研究以期为洞庭湖区土地利用、生态保护以及促进社会经济可持续发展提供科学参考。     

Interrelation between structure and protective action of normal and pathological ceruloplasmins during copper-induced lysis of red blood cells

The origin of the difference between the protective action of ceruloplasmin (CP) from healthy donors blood and of ceruloplasmin-like protein (p-CP) from blood of patients with Wilson disease which they exert during copper-induced lysis of red blood cells (RBC) was elucidated. The difference is due to a significant change in the carbohydrate moiety of p-CP the major proportion of which (65%) does not contain mannose and acetylglucosamine residues. The data of chromatography on lentil lectin reveal that only 4% of p-CP molecules contain the fragment [table: see text] required for binding to RBC receptors. It was shown that the time-courses of copper accumulation in RBC of normal donors and in RBC of patients with Wilson disease (p-RBC) during copper-induced lysis differ markedly from each other. The p-CP is able to prevent copper accumulation in RBC and p-RBC to a significantly less degree than CP. It was also established that CP prevents the decrease of reduced glutathione (GSH) level in RBC to a greater extent than p-CP. In contrast to CP, the p-CP exerts no effect on the decrease in GSH concentration in p-RBC. These results may indicate that no interaction between Cu2+ and reduced glutathione takes place in p-RBC, in contrast to the situation occurring in normal RBC.