Immunosuppressive activity of the blood serum of patients with cancer of the corpus uteri

In 40 patients with endometrial carcinoma of I-IV stage reaction of suppression of migration and adhesion of leukocytes (RSML and RSAL) in response to antigen prepared from the same tumour and in the presence of autoserum of blood of these patients, was studied. The index of antibody-forming cells (IAFC) and percentage of rosette-producing cells (RPC) in mice spleen after their infusion before immunization by sheep erythrocytes blood serum of the mentioned patients were also investigated. It was ascertained, that in all cases with using of autoserum of patients with endometrial carcinoma, especially on late stages, significant diminution of positive RSML and RSAL and decrease of IAFC and RPC take place. It was concluded that blood serum of patients with endometrial carcinoma gives evidence of immunosuppressive activity at late stages of the process.     

Soft X-ray emission from the plasma of a conductor exploding in a strong longitudinal magnetic field

Previous experiments with the electric explosion of conductors in a strong (50 T) longitudinal magnetic field showed the formation of a relatively low-density plasma around the central part of the explosion channel, which exhibited expansion at a velocity on the order of 10–20 km/s [1, 2]. Expansion of the plasma was accompanied by displacement of the magnetic field from the explosion channel, which was manifested by a diamagnetic signal. An analysis of the plasma energy balance is hindered by the lack of reliable data about radiative energy losses. Here, we report the first experimental results on the radiation pulse kinetics and the first estimates of the radiation energy.     

Response of the hypothalamic neurons to stimulation of the vestibular nerve and lateral vestibular nucleus in rabbits

Effects of single, double, and rhythmic stimulation upon hypothalamic neurons responding to the 1st excitatory phase of lateral vestibular nucleus stimulation, were studied. The data obtained show that activation of some hypothalamic neurons following stimulation of the lateral vestibular nucleus has a monosynaptic character. The findings suggest that ascending afferents from the lateral vestibular nucleus to the hypothalamus pass via oligo- as well as polysynaptic pathways.     

An IR-Radiometer with Internal Signal Modulation

An infrared (IR) radiometer electrical circuit on the basis of photoresistors and photodiodes made of silicon doped with zinc (Si<Zn>) as well as the narrow bandgap semiconductor alloy Pb_0.78Sn_0.22Te is presented. In the circuit suggested a bridge with the photoreceiver connected to the radiometer input and immediately fed by signal generators functions as a radiation modulator. The threshold sensitivity turned out on a recorder is 2·10^?13 W·Hz^?1/2 (for the n⁺?n?n⁺ structures made of Si<Zn>, λ=0.8?l.2μm, T=300K); 1.4·10^?15W·Hz^?1/2 (for p⁺?n?n⁺ S-diodes on the basis of Si<Zn>, λ=0.8?1.2μm, T=300K) and 10^?12W·Hz^1/2 (for photodiodes on the basis of Pb_0.78Sn_0.22Te, λ=8?13μm, T=77K).     

Functional role of vacuolization of the T-system of skeletal muscle fibers

T-tubules of skeletal muscle fibres easily transform into large vacuoles under the influence of various factors. These include osmotic shock produced by the efflux of small molecular weight molecules (e.g. glycerol), hypertonic shock, muscle fatigue and muscle damage. In most cases, vacuolation is reversible but the molecular mechanisms involved are not clear. Also, the functional role of reversible vacuolation has not been established. However, three possibilities may be considered. (1) Redistribution of ions and water between the cytoplasm and the extracellular space comprised by the T-system. Thus, the formation of large vacuoles may be a mechanisms for rapid osmoregulation that corresponds to regulated volume decrease in other types of cell. However, in our hands, inhibitors of various pathways that participate in volume regulation had no effect on reversible vacuolation. (2) Resealing of mechanical damage of the plasma membrane. This is usually accompanied by the development near the damaged membrane of numerous vacuoles which we have observed by confocal microscopy and use of a hydrophobic dye (RH414), to arise in part from T-tubules. (3) By confocal microscopy, it has also been shown that extracellular fluorescein dextran (Mr = 10,000), and both plasmid DNA (pUC18) and sonicated high molecular weight DNA stained with YOYO, enter vacuoles derived from T-tubules. This finding may indicate that reversible vacuolation, in the absence of membrane damage, could provide a pathway from the extracellular environment to the cytoplasm that is additional or complimentary to endocytosis; it may also be particularly relevant to the ability of muscle to be transfected by the direct injection of DNA. These several observations strongly indicate that the function of the T-system in skeletal muscle fibers is not restricted to excitation-contraction coupling.     

Effect of sterols on melittin incorporation into liposomal membranes

Effects of various sterols on the values of intensity, spectrum position and polarization of tryptophan fluorescence (P) of melittin incorporated in lecithin liposomes at different lipid/protein molar ratios (Ri) were studied. A difference in sterol effects has been revealed at the values of Ri > 5. At Ri < 5, fluorescence parameters were determined mainly by melittin in the aqueous solution. Assuming that melittin was bound to lecithin, the lecithin/melittin binding ratio was found to be in the range of 25-50. Unlike cholesterol and stigmasterol, the incorporation into membranes of ergosterol and 7-dehydrocholesterol produced a decrease in the intensity of tryptophan fluorescence and an increase in the P value. This difference might result from the presence of an additional double bond in one of sterol rings of ergosterol and 7-dehydrocholesterol molecules. Analysis of the results obtained enabled us to suggest that the structure of the steroid B ring is responsible for the effect exerted by sterols on melittin-lipid interactions.     

Investigations of solar cells with porous silicon as antireflection layer

The possibility of using porous silicon layers as antireflection coating instead of the antireflection coatings in common silicon solar cells was investigated. A technology for the manufacture of porous silicon antireflection layers was developed. The comparison of the photovoltaic and optical characteristics of investigated samples of solar cells with ZnS antireflection coating and with porous silicon antireflection coating is presented. It is shown that the formation of the porous layer under optimal technological regimes leads to significant improvement of the main photovoltaic parameters–short-circuit current and open-circuit voltage.     

High-energy radiation generated during electric explosion of a conductor in a longitudinal magnetic field

Our recent experiments [1] with the electric explosion of conductors in vacuum with an applied strong longitudinal magnetic field showed that this process was accompanied by radiation capable of penetrating through metal layers of considerable thickness. The high intensity of this radiation allowed it to be reliably detected outside the vacuum chamber using a photographic film with an amplifying luminescent (ZnS) screen situated in a paper envelope at a distance above 3 m from the region of explosion. In the same series of experiments, it was established that elements of the setup situated in the vicinity of the explosion exhibited residual radioactivity. This radioactivity was manifested, in particular, by flare spots on a photographic film in contact with an amplifying phosphor screen contained in a paper cassette that was placed inside the solenoid gap upon the discharge. No such explosion-induced radioactivity was observed in analogous experiments performed without an applied magnetic field. This paper presents the first results of investigations of the induced radioactivity, in which the activation detector was a gold ring situated at a distance of about 0.2 m from the axis of the exploding conductor.