Neuron correlates of the action result acceptor in a functional biotechnical complex structure

This study presents data illustrating neurophysiological features of the efferent-afferent convergence on the cortex neurons. It was established that, during the process of combining stimulation of the pyramidal tract (PT) axons with electrical skin reinforcement, a significant amount of neurons under study changed parameters of the activity evoked by the PT-stimulation. The most clear reconstruction of the PT-responses was obtained in experiments with inclusion of neurons into biotechnical complex by means of the feed back: "neuron-computer-stimulating devices-animal", representing an analogue of the functional system. The role of afferent-efferent convergence of the CNS neurons is discussed in dynamic deployment of the action result acceptor in the functional system of natural behavioural act.     

Formation of lysophospholipids from unsaturated phosphatidylcholines under the influence of hypochlorous acid

The formation of lysophosphatidylcholines from unsaturated phosphatidylcholines upon treatment with hypochlorous acid was evaluated by means of MALDI-TOF mass spectrometry and 31P NMR spectroscopy. With an increasing number of double bonds in a fatty acid residue, the yield of lysophosphatidylcholines with a saturated fatty acid residue increased considerably in comparison to the total amount of higher molecular weight products like chlorohydrins and glycols. High amounts of lysophosphatidylcholines were formed from phospholipids containing arachidonic or docosahexaenoic acid residues. In phospholipids with monounsaturated fatty acid residues, the position of the double bond did not influence the yield of lyso-products. Besides the exclusive formation of chlorohydrin and glycol, hypochlorous acid caused the cleavage of the unsaturated fatty acid residue independent of its location at the first or second position of the glycerol backbone. In contrast, strong alkaline conditions, i.e. saponification led also to a hydrolysis of the saturated fatty acid residue from phosphatidylcholines. It is concluded that both MALDI-TOF mass spectrometry and 31P NMR spectroscopy are able to detect the formation of lysophosphatidylcholines. We conclude also that the formation of lysophospholipids from unsaturated phosphatidylcholines by hypochlorous acid can be relevant in vivo under acute inflammatory conditions.     

Interaction of exogenous hypochlorite or hypochlorite produced by myeloperoxidase + H2O2 + Cl- system with unsaturated phosphatidylcholines

The interaction between unsaturated phosphatidylcholines and either exogenous or endogenous (produced by the enzyme system involving myeloperoxidase (MPO), H₂ O₂ ,and Cl^–) hypochlorite was studied in multilayer liposomes containing oleic, linoleic, and arachidonic acid residues using MALDI TOF mass spectrometry. At pH 7.4, hypochlorite reacts with the double bond of the oleic acid residue in 1-stearoyl-2-oleoyl-sn-glycero-3-phosphocholine producing oleic acid chlorohydrin as the main product. Minor amounts of glycols and epoxides were also detected. The main products of the reaction of hypochlorite with 1-stearoyl-2-oleoyl-sn-glycero-3-phosphocholine were mono and di chlorohydrins of linoleic acid. The signals of monoglycol, epoxide, and glycol or epoxide containing monochlorohydrin derivatives were also present in the mass spectrum. The main products of the reaction of hypochlorite with 1-stearoyl-2-oleoyl-sn-glycero-3-phosphocholine were lysophosphatidylcholine (1-stearoyl-2-oleoyl-sn-glycero-3-phosphocholine) and mono-, di-, and trichlorohydrin. Monoglycol and its derivatives containing one or two chlorohydrin groups were also detected. Along with those, carbonyl compounds (aldehyde and acid) formed as a result of double bond breakage in fifth position of arachidonate were detected. Monochlorohydrin was also found when liposomes comprising 1-stearoyl-2-oleoyl-sn-glycero-3-phosphocholine were incubated in the presence of enzymatic mixture, MPO +H₂ O₂ +Cl^–,at pH 6.0. In the absence of the enzyme or either of its substrates (H₂ O₂ or Cl^–) or in the presence of the MPO inhibitor (sodium azide) or hypochlorite scavengers (taurine or methionine), monochlorohydrin formation was not observed. These data confirm the suggestion that just the hypochlorite generated in MPO catalysis provides for chlorohydrin formation. Thus, the use of MALDI TOF mass spectrometry has shown, along with chlorohydrins, glycols and epoxides as the products of hypochlorite interaction with unsaturated phosphatidylcholines at physiological pH. It was first determined that hypochlorite breaks double bonds in polyunsaturated phosphatidylcholine and also causes lysophosphatidylcholine formation.     

Delayed effects of acute radiation injuries by radioactive carbon (14C-glycine)

A study was made of late biological effects of radioactive carbon (14C-glycine) applied in acute doses. The course of radiation sickness, at its acute stage, is similar to that of acute radiation sickness caused by external gamma-irradiation. The recovery is slow, and the disease becomes chronic exhibiting metabolism disturbances and early death of animals. Radioactive carbon has a pronounced blastomogenic action.     

Low-Molecular-Weight Autoregulatory Factors in the Haloalkaliphilic Bacteria Thioalkalivibrio versutus and Thioalkalimicrobium aerophilum

The haloalkaliphilic, lithoautotrophic, sulfur-oxidizing gram-negative bacteria Thioalkalivibrio versutus and Thioalkalimicrobium aerophilum were found to possess a special system for the autoregulation of their growth. The system includes the extracellular autoinducers of anabiosis (the d₁ factor) and autolysis (the d₂ factor). The principal components of the d₁ factor are alkylhydroxybenzenes, as evidenced by specific qualitative reactions. The principal components of the d₂ factor are free unsaturated fatty acids dominated by oleic acid isomers. Like the respective autoregulators of neutrophilic bacteria, the d₁ factor of haloalkaliphilic bacteria presumably controls their growth and transition to anabiotic state, while the d₂ factor controls autolytic processes. Alkylhydroxybenzenes of both microbial and chemical origin were found to influence bacterial respiration. The low-molecular-weight osmoprotectant glycine betaine enhanced the thermostability of trypsin. This suggests that both glycine betaine and the d₁ factor serve as chemical chaperones.     

Measurement of the rate of O2 consumption by peritoneal macrophages using electron paramagnetic resonance

To study the process of activation of macrophages by silicon dioxide particles, use was made of an electrode-free method for measuring the O2 consumption rate. It was discovered that within the first minute of interaction with silicon dioxide particles the rate of O2 consumption by peritoneal macrophages rose 3-4-fold.     

Genetic Variability and the Potential Range of Darevskia rostombekowi in Transcaucasia

Biology Bulletin - The results of the analysis of the genetic variability of parthenogenetic Darevskia rostombekowi (Darevsky, 1957) species using four microsatellite-containing loci are presented....     

重组人MASP2蛋白在大肠杆菌中的表达和纯化

目的:获得酶原形式的重组人甘露聚糖结合凝集素相关丝氨酸蛋白酶2(MASP2)。方法:在大肠杆菌中诱导表达重组人MASP2全长蛋白,包涵体裂解后,经复性、透析、浓缩、考马斯亮蓝染色、SDS-PAGE及Western印迹,鉴定纯化结果及酶活性。结果:复性后的MASP2蛋白经考马斯亮蓝染色未见杂带。自激活实验表明,当MASP2浓度在1μmool/L以下时,无论在4℃还是37℃,都能较稳定地保持酶原形式;蛋白浓度为3.5μmool/L时只能在4℃保持稳定,37℃发生自激活;蛋白浓度达到12μmool/L后,在4℃时已不能稳定存在。结论:获得了较纯的重组人MASP2蛋白,且具有自激活活性。     

Features of the metabolism of nitric oxide in normal state and inflammation

Brief analysis of the metabolism of nitric oxide in living cells in normal state and pathology and also the analysis of the causes that hampered the progress of these studies were carried out. It was established that most of physiological fluids, including blood, normally contain nitrite and non-thiolate nitroso compounds in concentration less than 100 nM. Literature data from different researchers on the normal range of nitrite concentration in plasma of healthy people from several hundreds of nM to several μM is probably the result of low selectivity of the methods used. But nitrite and non-thiolate nitroso compounds concentration in blood is dramatically increased in case of inflammatory diseases. It is proposed that the main mechanism for the production of these substances in blood is the nitrosyl iron complexes transformation by active oxygen species but not the activation of NO production as it was considered previously.