The effect of microwaves on the bioelectric brain activity

The experiments on rats have shown that the effect of millimeter range electromagnetic radiation on the bioelectric brain activity is dependent on the initial functional state of central nervous system. Microwaves are able to cause a nonspecific electroencephalographic reaction of synchronization and probably the lower the bioelectric brain process dynamics of active rats. Enrichment of electrocorticograms with high-frequency rhythms and increase in degree of bioelectric brain dynamics can be observed in narcosis conditions. The appearance of biological resonance in the brain of narcotized rats preliminary injected aminazin by pulse-modulated microwaves is noted. This is expressed as epileptiform convulsive activity in electrocorticogram. It has been shown that the nonlinear dynamics method may provide a reliable characterization of changing bioelectric brain activity under of nonionized electromagnetic fields. It is possible to modulate the bioelectric brain activity by microwaves to change the functional state of central nervous system and probably of the whole organism.     

Photoperiodism and changes in brain bioelectric activity in schoolchildren in the arctic zone

The dynamics of the main electroencephalographic patterns and their relationship with natural illumination periods have been described in this study. We have determined periods, which are the most favorable for brain functioning and development of cognitive function in northerner schoolchildren. We have found that adaptive changes in bioelectric activity of the brain take place during transitional seasons. An increase in the activity of all EEG rhythms in spring and predominance of the slow-wave Δ and θ activity in autumn have been found. The discovered dynamics of amplitude and spectral parameters of EEG are not dependent on age-related changes. The formation of bioelectric activity of the brain in northerner schoolchildren was mostly affected by the sex of a child and changes in the daytime duration.     

Neuronal Networks on Multielectrode Arrays as High Sensitive Biosensors of the Functional State of Nerve Cells

The dynamics of changes of spontaneous neuronal activity in primary hippocampal cell cultures developing on a multielectrode array (MEA) was studied using a multielectrode system. The intensification of bioelectrical activity, which depended on the duration of cultivation and stabilized by the second week in vitro, has been revealed. An increase in the concentration of glutamate (up to 2 μM) by addition into the incubation medium during the stabilization period resulted in a rapid and significant reorganization of the neuronal network activity pattern. On the other hand, inhibition and subsequent gradual recovery of the neuronal network activity immediately after the neurotransmitter addition at higher concentrations (50 or 100 μM) have been observed. At the same time, on some electrodes in the presence of high doses of glutamate (100 μM), a complete or partially irreversible suppression of the activity has been recorded. A significant reduction in spontaneous activity of the neuronal network, which was not accompanied by neuronal death, also occurred when copper ions (Cu²⁺) at a concentration of 10 μM were added into the incubation medium for 48 h. The obtained data demonstrate high biosensor sensitivity of the neuronal network cultured on the multielectrode array, which makes it possible to use it as an effective test system for studies of biologically active compounds.     

The human body response to factors related to solar activity variations

The effect of nonstationary solar processes on human organism was studied. Daily measurements of electrical conductivity of 22 biologically active points on human skin, arterial pressure, and pulse frequency of 30 persons were performed, and their subjective sensations were registered. A comparative analysis of the data and variations in environment parameters, such as local A-index, atmospheric pressure, temperature, and indices of cosmic rays indicated a coincidence of their main periods. The conclusion is made that the reaction of the human organism on abrupt solar disturbances is biphasic and that there is a semiannual wave of synchronization of work of internal organs. The results are confirmed by simultaneous measurements in different cities.     

Behavioral Activity and Anxiety of Rats under Open Field Conditions in the Norm and after Parenteral Introductions of Xenogenic Cerebrospinal Fluid

We studied the effects of injections of xenogenic cerebrospinal fluid (CSF) on behavioral phenomena in rats under open field conditions. Parenteral introduction of xenogenic liquor in adult male and female rats resulted in appreciable changes in the indices of spontaneous motor activity in the open field. Single and double CSF injections promoted intensification of motor and orientational/research activity followed by inhibition of the respective behavioral manifestations. Repeated CSF injections were accompanied by a gradual decrease in the behavioral activity of rats. In males and females, these changes were nearly synchronous. Injections of CSF also influenced the seasonal dynamics of behavioral phenomena in rats and cyclic changes in the activity of females during the estrous cycle. In the whole, CSF injections exerted more powerful effects than the action of main natural biological regulators (photoperiod and sex cycle). The presence of significant amounts of biologically active substances in the liquor, which are responsible for complex effects on links of the neuroendocrine regulatory system of recipients, is the probable basis of the revealed effects.     

Comprehensive bioelectrographic analysis of mechanisms of the alternative state of consciousness

Using complimentary capacities of modern computer technologies, such as digital electroencephalography and recording of current parameters of meridional biologically active points and evoked energy emission processes, the authors studied the bioelectrographic correlates of an alternative state of consciousness. The phenomenon of phasic activation of energy emission processes during the accomplishment of mental activity in an alternative state of consciousness was revealed for the first time. The data obtained are analyzed from the viewpoint of the specific features of neurophysiological and psychophysical mechanisms of the formation of alternative states of consciousness in conditions of systematic mental training.     

Effect of modified SHF and acoustic stimulation on spectral characteristics of the electroencephalograms of the cat brain

The effect of modulated electromagnetic fields on the spectral parameters of bioelectric brain activity in awake cats was studied by registering the electroencephalogram from the skin surface in the vertex area using carbon electrodes. In the normal electroencephalogram, spectral components in the range above 20 Hz predominated. It was shown that, upon irradiation with electromagnetic field (basic frequency 980 MHz, power density 30-50 microW/cm2), spectral components in the range of 12-18 Hz begin to prevail. A similarity in the redistribution of the power of spectral components upon both acoustic and modulated electromagnetic influences was revealed. The results suggest that there is a a common neurophysiological mechanism by which modulated electromagnetic radiation and acoustic stimulation affect the electrical activity of the brain. This ia consistent with the assumption that the effect of the electromagnetic field on the central nervous system is mediated through the acoustic sensory system.     

Reaction of the biologically active points of the skin to immunization with typhus vaccine

Electroacupuncture diagnosis was used to demonstrate the reaction of biologically active points of the skin (BAPS) to immunization with typhus vaccine. In 7 persons immunized with chemical and live (strain E) typhus vaccines, the reaction differed significantly from the initial parameters and other measurement data obtained in a group of unvaccinated subjects. The reaction of the BAPS was noticeable starting from the first day after vaccination and was far ahead of seroimmune shifts detectable in the host. The best correlation was established between the seroimmune response and the activity of the acupuncture points on meridians X and I (a positive correlation) and on meridians III, VIII and XI (a negative correlation).     

Memory in idiotypic networks due to competition between proliferation and differentiation

A model employing separate dose-dependent response functions for proliferation and differentiation of idiotypically interacting B cell clones is presented. For each clone the population dynamics of proliferating B cells, non-proliferating B cells and free antibodies are considered. An effective response function, which contains the total impact of proliferation and differentiation at the fixed points, is defined in order to enable an exact analysis. The analysis of the memory states is restricted in this paper to a two-species system. The conditions for the existence of locally stable steady states with expanded B cell and antibody populations are established for various combinations of different field-response functions (e.g. linear, saturation, log-bell functions). The stable fixed points are interpreted as memory states in terms of immunity and tolerance. It is proven that a combination of linear response functions for both proliferation and differentiation does not give rise to stable fixed points. However, due to competition between proliferation and differentiation saturation response functions are sufficient to obtain two memory states, provided proliferation preceeds differentiation and also saturates earlier. The use of log-bell-shaped response functions for both proliferation and differentiation gives rise to a “mexican-hat” effective response function and allows for multiple (four to six) memory states. Both a primary response and a much more pronounced secondary response are observed. The stability of the memory states is studied as a function of the parameters of the model. The attractors lose their stability when the mean residence time of antibodies in the system is much longer than the B cells' lifetime. Neither the stability results nor the dynamics are qualitatively chanbed by the existence of non-proliferating B cells: memory states can exist and be stable without non-proliferating B cells. Nevertheless, the activation of non-proliferating B cells and the competition between proliferation and differentiation enlarge the parameter regime for which stable attractors are found. In addition, it is shown that a separate activation step from virgin to active B cells renders the virgin state stable for any choice of biologically reasonable parameters.     

Effect of a high-intensity radiation exposure on brain function in monkeys. Postradiation changes in central coordination of brain bioelectrical processes

In experiments with Macaca fascicularis exposed to high-energy electrons (45 Gy, 6.5 Gy/s) revealed were early changes in the coherent spectrum of EEG semihemispheric leads. These changes were displayed by the increased interrelation between slow-wave fluctuations and decreased coherence within the mid- and high-frequency EEG-rhythms band. The relationship was noted between the changes observed and the clinical symptoms features of early radiation response as well as the dynamics of the CNS functions of exposed animals. Postirradiation changes in the intracellular bioelectric interaction are considered as one of the manifestations of the systemic response of the brain to the harmful effect of radiation.     

High-level expression and purification of biologically active recombinant pokeweed antiviral protein.

Pokeweed antiviral protein (PAP) from the leaves of the pokeweed plant, Phytolacca americana, is a naturally occurring single-chain ribosome-inactivating protein, which catalytically inactivates both prokaryotic and eukaryotic ribosomes. The therapeutic potential of PAP has gained considerable interest in recent years due to the clinical use of native PAP as the active moiety of immunoconjugates against cancer and AIDS. The clinical use of native PAP is limited due to inherent difficulties in obtaining sufficient quantities of a homogenously pure and active PAP preparation with minimal batch to batch variability from its natural source. Previous methods for expression of recombinant PAP in yeast, transgenic plants and Escherichia coli have resulted in either unacceptably low yields or were too toxic to the host system. Here, we report a successful strategy which allows high level expression of PAP as inclusion bodies in E. coli. Purification of refolded recombinant protein from solubilized inclusion bodies by size-exclusion chromatography yielded biologically active recombinant PAP (final yield: 10 to 12 mg/L). The ribosome depurinating in vitro N-glycosidase activity and cellular anti-HIV activity of recombinant PAP were comparable to those of the native PAP. This expression and purification system makes it possible to obtain sufficient quantities of biologically active and homogenous recombinant PAP sufficient to carry out advanced clinical trials. To our knowledge, this is the first large-scale expression and purification of biologically active recombinant PAP from E. coli.     

Characterization and purification of the biologically active v-sis protein generated in silkworm larvae with the Bombyx mori nuclear polyhedrosis virus vector system

The v-sis oncogene of simian sarcoma virus encodes a protein which is homologous to the human platelet-derived growth factor B-chain. The biologically active v-sis protein was expressed in silkworm larvae using the Bombyx mori nuclear polyhedrosis virus vector system. The v-sis protein purified from infected silkworm larvae is a 30 kDa disulfide-linked homodimer. Mitogenic activity of the v-sis protein was comparable to that of PDGF and inhibited by the pretreatment with anti-PDGF antibody. These results show that the recombinant v-sis protein is biologically and antigenically related to PDGF.     

Efficient synthesis and biological evaluation of omega-oxygenated analogues of vitamin K2: study of modification and structure-activity relationship of vitamin K2 metabolites

Novel omega-oxygenated vitamin K2 analogues, which are candidates for metabolites of vitamin K2 homologues, were efficiently synthesized and their apoptosis-inducing activity was evaluated. We revealed that some of those analogues were biologically active and the side-chain part played an important role in apoptosis-inducing activity. Our results can provide useful information to develop the structure-activity relationship of vitamin K2 analogues for new drugs based on vitamin K.     

Flexible polyimide probes with microelectrodes and embedded microfluidic channels for simultaneous drug delivery and multi-channel monitoring of bioelectric activity

The study of intracellular communication requires devices that can not only monitor the bioelectric activity, but also control and observe the biochemical environment at the cellular level. This paper reports on the development and characterisation of implantable polyimide microprobes that allow simultaneous, selective chemical delivery/probing and multi-channel recording/stimulation of bioelectric activity. The key component of the system is a flexible polyimide substrate with embedded microchannels that is batch-fabricated combining polyimide micromachining and a lamination technique. The devices provide platinum microelectrodes on both sides of the polyimide substrate with an active surface between 20 microm x 20 microm and 50 microm x 50 microm. The embedded microchannels permit highly localised drug delivery or probing at the tip of the device via channel outlets adjacent to the microelectrodes. The microelectrodes were characterised by electrical impedance spectroscopy and the microchannels were studied in microflow experiments. Two different fluid delivery schemes were explored in two different designs. The first device type consists of a simple combination of microchannels and microelectrodes on one substrate. Liquids are ejected at the tip of the device by pressure injection techniques. The second device was inspired by the so-called U-tube concept allowing for highly localised delivery of controlled amounts of liquids in the picoliters range. Thus, the influence of chemical compounds on the electrical activity of cells can be studied with high temporal and spatial resolution. The flexible, implantable devices can be used for studying the chemical and electrical information exchange and communication of cells in in vivo and in vitro experiments.     

Formation of microparticulate protein powder using a supercritical fluid antisolvent

Gas antisolvent (GAS) expansion of dimethylsulfoxide (DMSO) and N,N-dimethylformamide (DMFA) solutions with supercritical carbon dioxide was used to produce biologically active powders of insulin. Powders with 90% of the particles smaller than 4 mum and 10% smaller than 1 mum were obtained under all conditions tested when the process was operated continuously, with small liquid droplets sprayed into a flowing supercritical continuum. Slow pressurization of the stagnant protein solution resulted in larger particles. In vivo tests on rats revealed no differences between the biological activity of processed and unprocessed insulin, GAS processing of organic solution appears to be a reliable and effective method for the production of dry, biologically active microparticulate powders of peptides and proteins. (c) 1993 John Wiley & Sons, Inc.     

Correlation between the sizes of Drosophila populations and parameters of solar activity

The relationship between the time series of the dynamics of the numbers of experimental populations of Drosophila melanogaster at the preimaginal stage and three heliogeophysical indices: Wolf numbers, the intensity of the 10.7-cm radio flux, and the Kp-index of geomagnetic activity was analyzed. Statistically significant data were obtained indicating that the dynamics of the number of the populations is related to the heliogeophysical factors, and this relationship depends on the phase of the 11-year cycle of solar activity. It was shown that the fertility of females and the survival of eggs is stimulated by factors associated with solar activity.