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Poli(U)-dependent binding of yeast tRNA(Phe) lacking the 3'-terminal CA or CCA residues, and fragments of tRNA prepared by splitting the tRNA(Phe) at the G18 or 7mG46 nucleotides, to the 70S ribosomal P-site was studied. Equilibrium binding constants and free energies of binding were measured. The contribution of C74 and C75 was estimated at 3.9 kJ/mol and 3.0 kJ/mol, respectively, at 10 mM Mg2+ and 30 degrees C. The free energies of the binding of the anticodon arm the tRNA lacking its CCA terminus, and the tRNA fragment containing bases N1-N45 were found to be nearly equal. These results indicate that only the anticodon arm and the CCA terminus take part in deacylated tRNA-P-site interaction.

Spatial light modulators (SLM) are considered as the main elements of optical data processing systems. Liquid crystal SLMs (LCSLM) having high performance parameters are normally used in optical systems as image transducers and optical filters. The value of LCSLM for optical data processing is increased by combining image transducing and image preprocessing functions in the same sample. Such a combination improves the flexibility and productivity of optical data processing methods, and simplifies optical setup. Among realized preprocessing functions of LCSLM are the edge enhancement, the selection of nonstationary objects, the optical analog of lock-in-amplifier, image subtraction, and spatial selection of the image details corresponding to their intensity. Most of mentioned preprocessing functions and new features like IR-sensitivity, IR-modulation are primarily realized in LC SLM at P.N.Lebedev Institute. The physical mechanisms for these opportunities are discussed together with possible improvements in parameters and features. Recently observed new electro-optical effects in ferroelectric liquid crystals are reported as ones giving new opportunity to combine image preprocessing and fast response.

An IR-spatial filter is proposed for usage in a focal plane. This filter screens the IR-array locally, where the IR signal is followed by a signal in the visible region (only noisy signals or jamming interferences are assumed to be followed by visible light). The filter discussed here is based on a photosensitive spatial light (IR) modulator, abruptly diminishing its transmittance in IR, when (and where) visible light intensity is over the settled threshold. The experiments were performed when the attenuation of interference was about one order.

The poly(U)-dependent bindings of yeast tRNAPhe, its derivative depleted of 3'-terminal adenosine, and 15-nucleotide having a sequence of yeast tRNAPhe anticodon arm to the P site of Escherichia coli 70S ribosomes were compared. The equilibrium and rate constants were determined. Data indicate that the anticodon arm (N28-N42) contributes the major fraction of the binding free energy (-45.3 kJ/mol at 10 mM Mg2+ and 30 degrees C). Other parts of the tRNAPhe molecule besides A76 (N1-N27 and N43-N75) bring additional-6.0 kJ/mol, and A76 contributes-2.4 kJ/mol.

The review of the literature data and the authors' data on interferon action inhibitors being one of the components of interferon system is presented. The methods of the production of various types of interferon action inhibitors, their characteristics and the main differences between them are described. The possible mechanisms of inhibitors' actions are considered. It was shown that the study of interferon action inhibitors is important in both the theoretical and practical aspects.

The results of the clinical trials of human recombinant interferon alpha-2 (reaferon) make it possible to come to the conclusion that the preparation is well-tolerated and produces a pronounced therapeutic effect in a number of viral and oncological diseases. The Pharmacological Committee of the USSR has recommended reaferon for use in acute hepatitis B, hairy cell leukemia, renal cancer at stage IV, disseminated sclerosis, ocular herpes. The use of reaferon has been found to be promising in the treatment of papillomatosis of the larynx, Kaposi's sarcoma, mycosis fungoides, chronic myeloleukemia.

Clinical trials of the gene engineered human alpha 2-interferon as ointment were performed. The ointment was used in the treatment of patients with relapsing herpes of various localization, relapsing aphthous stomatitis and pemphigus vulgaris. It was shown that the ointment was harmless and its therapeutic effect was favourable. The preparation is recommended for introduction into the practice of public health.

A stability of homeotropically aligned C*FLC layer and the optical response 20 μs in electric field 2 4 V/μm at room temperature are advantages for fast FLC devices.

A review is given of recent progress in the development and applications of spatial light modulators (controlled transparencies) in the form of photosensitive multilayer structures containing a liquid crystal. A considerable improvement is reported in the most important parameters of the process of modulation of light such as the sensitivity (now 10−11 J/cm2), resolution (now 300 mm−1), and speed of response (hundreds and thousands of frames per second). There has been an expansion in the functional capabilities: the modulators can now handle infrared radiation, identify boundaries of objects and regions with time-dependent illumination in converted images, modulate light at one or several stable transmission levels, etc. Some new applications are described, particularly those in processing of television images and in real-time interferometry.

An investigation was made of spatial light modulators utilizing the electrooptic effects in a liquid-crystal layer, acting as the insulator in a photosensitive metal–insulator–semiconductor structure. The semiconductor was a crystal of bismuth silicate or germanate. A high value of the energy sensitivity, up to 2 cm2μJ (for total modulation of light), was obtained; the intensity of the control (switching) light in the blue part of the spectrum was 25–30 μ W/cm2. The resolution was up to 200 lines/mm (deduced from the fall to half the maximum value of the frequency-contrast characteristic). The liquid crystals employed made it possible to reach a frame repetition frequency of 30–50 sec−1 at room temperature. A two-frequency supply of the modulator structure made it possible to achieve a controlled memory regime with a data storage time up to 2 sec, and with recording and erasure times of ~1 msec.

An investigation was made of spatial modulation of light in structures formed from an insulated semiconductor and a liquid crystal. It was found that the modulation parameters (sensitivity and resolution) were influenced strongly by the accumulation of carriers in the semiconductor when the structure was subjected to an alternating voltage. A resolution of about 100 lines/mm and a sensitivity down to 10−9 J/cm2 were achieved for a structure with gallium arsenide as the semiconductor.

An experimental study revealed the absence of competitive suppression of one of the counterpropagating waves in a rotating YAG:Nd3+ ring laser operated under transient acoustooptic mode locking conditions. This absence was attributed to different time shifts of the counterpropagating ultrashort pulses relative to a loss minimum in a modulation period on increase in the difference between the eigenfrequencies of the counterpropagating waves in the ring resonator. Two new ways of determination of the velocity of rotation of a solid-state ring laser were developed: one is based on splitting of the frequencies of cophasal modulation of the intensities of the counterpropagating waves under transient mode locking conditions and the other is based on the frequencies of relaxational oscillations under mode locking conditions.

A description is given of a number of optical devices which can be used in interferometry, holography, and optical information processing. Feedback in an optically controlled spatial modulator makes it possible to stabilize the intensity of laser radiation (temporally and spatially), to make an intensity modulator, and to perform image filtering. Probably the most interesting is the realization of a dynamic memory which, in particular, can be used to convert an image into binary form. An important use for devices with feedback is to solve equations of mathematical physics.

The use of optical methods for the investigation of the electronic structure of oxide ferrimagnets is complicated by the large variety of possible types of electron transitions whose energies are close to each other and lie in the near infrared, visible, and near ultraviolet regions of the spectrum. Therefore, for the correct identification of the transitions, it is desirable to apply traditional optical spectroscopy, which permits quantitative evaluation of the transition intensities (oscillator strength), in conjunction with magnetooptical (MO) methods providing information on weak intraconfigurational transitions which are not manifest in ordinary absorption or reflection spectra.

Methods of the realization of a tabular optical processor with variable operators are considered. The structure and functional links between the units of the processor are discussed. A detailed analysis is made of the operation of a unit of controlled light beams, units for recording and readout of holograms, immediate-access memory, and a data processing unit made up from optically controlled transparencies. Difficulties and prospects of the construction of optical and optoelectronic variants of this new high-performance processor are considered. It is noted that the optoelectronic variant of the processor may be realized within a few years.

Theoretical and experimental investigations were made of the scattering of surface electromagnetic waves at an interface between a metal and a liquid crystal in metal–insulator–metal–liquid crystal structures. Surface electromagnetic waves were created as a result of electron tunneling in the metal–insulator–metal part of a structure and these waves were scattered by a periodic inhomogeneity of the permittivity of the liquid crystal.

The influence of the flame retardant chemical tris(2,3-dibromopropyl) phosphate, and the related chemical species, tripropyl phosphate and 2,3-dibromopropanol, on the products of pyrolysis of poly(ethylene terephthalate), has been examined as a function of chemical concentration. The species containing phosphourus only and bromine only had little effect on the composition and concentration of the pyrolysis products. The tris(2,3-dibromopropyl) phosphate had a significant effect upon the pyrolysis product distribution, and is capable of influencing the decomposition reactions of poly(ethylene terephthalate).

The results of an experimental investigation of the operation of an electrode in argon containing 0.15% of potassium at temperatures from 1400 to 1800 °C and a pressure of 1 atmosphere when the gas and the electrode are in thermal equilibrium are presented. The current-voltage characteristics obtained are compared with the theory of electrode processes developed previously [1, 2]. Good agreement is obtained between the theoretical and experimental data.

A study was made of light emitted as a result of decay of surface plasma oscillations in metal–oxide–metal structures. An absolute increase in the intensity of this light and its control were achieved by using a medium external to the metal film. This medium was a liquid crystal forming a domain structure in a static electric field. The arrangement provided a convenient means for investigating the processes of radiative decay of surface plasmons.

The results of the study of the antiproliferative effect of swine leukocyte interferon and of an inhibitor of interferon effect in experimental mice with transplanted Krebs-2 ascitic carcinoma cells are presented. The interferon inhibitor exerted antiproliferative effect similar to that of native swine interferon. Combined use of swine interferon and interferon inhibitor did not lead to summation of the antiproliferative effect of these preparations.

In the presence of methanol 50S ribosomal subunits reveal two independents sites for binding of deacylated tRNA and/or AcPhe-tRNA. The site with lower affinity was identified with the donor (P') site as the dissociation constant (Ka) for AcPhe-tRNA was equal to the Michaelis constant for its reaction with puromycin both at 0 degrees C and 25 degrees C. Log Ka increases linearly with methanol concentration. This suggests that there are no conformational transitions of the interacting components, the affinity increases only quantatively due to lowering of the dielectric constant of water, and the site can exist even in the absence of methanol, but its Ka may be too low to be measured. It follows from these data that the higher-affinity site, which is observed both in the absence and presence of methanol, cannot be the P' site as it was generally believed. By all its properties it is more like the additional E site, which has been recently found on 70S ribosomes. Specifically, its affinity for deacylated tRNA is about 1000-fold higher than for AcPhe-tRNA (in the P'-site they are almost the same).

Studies on the antagonists of interferon effect ("stimulon", "TAI", "blocker", "antiinterferon") formed under the influence of viruses and mitogens as well as those found in noninfected tissues deal largely with their blocking effect on the antiviral activity of interferon. Previously we had found an inhibitor of antiviral effect in preparations of human cadaverous and swine leukocyte interferons. This paper presents the results of studies on some physico-chemical properties of an inhibitor of the effect of swine leukocyte interferon and its antiproliferative activity. The inhibitor is resistant to the effect of nucleases and lyophilization, manifests limited heterospecificity towards interferons and cell cultures, has marked antiproliferative activity in different cell cultures including those of tumor origin.

The use of the routine method for inactivation of the inductor virus by acidification of interferon to pH 2.0 resulted in a significant decrease in the antiviral activity of pig leukocytic interferon, since the preparation was highly sensitive to changes in the pH values. The use of 0.1 per cent solution of formalin provided complete inactivation of the virus. The antiviral activity of interferon treated with formalin was on an average 5 times higher than that of the preparation incubated at pH 2.5-2.6. Precipitation of pig interferon with polyethylene glycol promoted both increasing of the titers of the antiviral activity of the preparation and elimination of the formalin residues from it. Interferon prepared with this procedure was not toxic in tissue cultures, had no side effects when applied to the eye mucosa and was absolutely harmless when administered to animals. It was shown that inactivation of the inductor virus with formalin was in principle possible in human leukocytic interferon.

A comparative study of different methods for concentration of porcine leukocyte interferon active in human cells was carried out. Ultrafiltration in an apparatus TCF-10 was found to be the most effective method of concentration by which preparations of porcine interferon showing antiviral activity up to 1 X 10(6) IU/ml were obtained. The total antiviral activity of concentrated interferon was twice as high as that of the native preparation. This increase of the total initial activity is due to the removal in the process of concentration of an inhibitor of antiviral activity which was isolated and concentrated. The concentrated preparation of porcine leukocyte interferon is now undergoing trials in veterinary and medicine.

The results of the experimental (preclinical) study of interferon alpha2 from Pseudomonas sp VG-84 obtained from the All-Union Research Institute of Genetics and Selection of Industrial Microorganisms in comparison with the preparations of interferon alpha2 from E. coli 74 and natural human interferon (obtained from the Gamaleya Institute of Epidemiology and Microbiology) are presented. Interferon alpha2 from Pseudomonas, a highly purified preparation, has been shown to possess pronounced biological activity (antiviral and antiproliferative) in the culture of human cells. The medicinal form of the preparation has proved to be completely safe and areactive for animals, which makes it possible to recommend the preparation for testing on volunteers.

An ointment containing porcine leucocytic interferon (PLI) with the use of lanolin as the base and addition of human serum albumin for stabilization of the antiviral activity and Tris-or Hepes-buffer solutions for stabilization of the medium pH value was studied. The trials on volunteers with herpetic affections of the face and genitalia showed absolute safety of the drug, its areactivity and sufficiently high therapeutic efficacy as compared to an ointment containing human leucocytic interferon. The positive effect was observed in 52 out of 78 patients. On the basis of these data the PLI may be recommended for further clinical trials.

A simple method for increasing the activity of human leukocyte interferon is described. It is based on the removal from the native preparation of a presumed inhibitor of antiviral effect followed by condensation of the resulting fractions by thin-canal cells TCF-10 of an Amicon apparatus. With this method of concentration there was no loss of the general initial antiviral activity. Depending on the titer of the initial interferon and the condensation degree, the native interferon was concentrated 32--350-fold. The resulting concentrated interferon preparation is nontoxic, areactogenic, safe in animal trials and may be recommended for trials as a therapeutic-prophylactic means in various viral diseases.

The ointment containing pig leukocytic interferon had a pronounced therapeutic effect in herpetic affections of the face skin and genitalia. It prevented eruption, shortened the period of its healing and eliminated subjective sensations. The therapeutic effect was observed in 265 (87.7 per cent) out of 302 patients with recurring Herpes simplex treated with ointment.

Different means of attenuating the leukemogenic activity were studied comparatively with a continuous strain of bone marrow cells derived from mice infected with Rauscher leukemia virus. Treatment of leukemic cells with neuraminidase, like their cultivation at suboptimal temperature resulted in a complete loss of leukemogenic activity, as evidenced by 100% survival of experimental animals and the absence of splenomegaly. In parallel experiments with concanavallin A and 5-bromdeoxyuridine treatment, development of splenomegaly was retarded and lethality of the animals reduced by 70 and 20%, rnd 20%, respectively. These results permit to raise the problem of using the above-memtioned methods for the attenuation of leukemogenic activity as an approach to prepare material with the immunizing activity.

We review the present status of the Baikal Neutrino Project and present results of a search for upward going atmospheric neutrinos, WIMPs and magnetic monopoles obtained with the detector NT-200. Also, the results of a search for very high energy neutrinos are presented. An upper limit on the v e+v μ+v T neutrino diffuse flux of E 2 · F(E) < 1.3 · 10 -6 cm-2 s-1 sr-1 GeV within a neutrino energy range 104 ÷ 107 GeV is obtained, assuming an E -2 behaviour of the neutrino spectrum and flavor ratio v e+v μ+v T = 1: 1: 1- We describe the moderate upgrade of NT-200 planned for the next years and discuss a possible detector on the Gigaton scale.

We synthesized a series of new di-cholesteryl esters of several diacids. One of the compounds containing both of a diyne unit and long alkylene units, in the form of a thin solid film, showed stable iridescent colours in the visible region after rapid cooling process from the temperature of the cholesteric liquid crystalline phase. Measurement of selective reflectance of visible light, X-ray diffraction, optical rotation dispersion of the solid films proved that the films remained the cholesteric ordering of the molecules. The cholesteric structure in the solid films were completely stable at room temperature. The colour of the solid film was totally, partially or in imagewise manner changed into selected colours by adjusting the temperature of the surface just before the rapid cooling process. The property of this compound can be applicable to memory media with high density using the spectrum of light, or to thermosensitive full-colour recording materials.

We review the present status of the Baikal Neutrino Project. The construction and performance of the large deep underwater Cherenkov detector NT-200 with 192 PMTs [1], which is currently taking data in Lake Baikal, are described. Some results from intermediate detector stages are presented.