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We studied blood serum levels of neurosteroids, dehydroepiandrosterone and its sulfate, in individuals with personality disorders convicted of serious violent crimes. The data were compared with that of a group of mentally and physically healthy persons convicted of acquisitive crimes, and with that of the control group. Significant increase in DHEA in both groups of convicts in comparison with the control was shown. The level of dehydroepiandrosterone sulfate remained unchanged. Increased dehydroepiandrosterone level in the convicted individuals with personality disorders is probably more associated with detention stress than directly with psychopathology or criminal aggression.

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One of the protective mechanisms used by plants to survive under conditions of salt stress caused by high NaCl concentration is the removal of Na+ from the cytoplasm. This mechanism involves a number of Na+/H+-antiporter proteins that are localized in plant plasma and vacuolar membranes. Due to the driving force of the electrochemical H+ gradient created by membrane H+-pumps (H+-ATPases and vacuolar H+-pyrophosphatases), Na+/H+-antiporters extrude sodium ions from the cytoplasm in exchange for protons. In this study, we have identified the gene for the barley vacuolar Na+/H+-antiporter HvNHX2 using the RACE (rapid amplification of cDNA ends)-PCR (polymerase chain reaction) technique. It is shown that the identified gene is expressed in roots, stems, and leaves of barley seedlings and that it presumably encodes a 59.6 kD protein composed of 546 amino acid residues. Antibodies against the C-terminal fragment of HvNHX2 were generated. It is shown that the quantity of HvNHX2 in tonoplast vesicles isolated from roots of barley seedlings remains the same, whereas the rate of Na+/H+ exchange across these membranes increases in response to salt stress. The 14-3-3-binding motif Lys-Lys-Glu-Ser-His-Pro (371-376) was detected in the HvNHX2 amino acid sequence, which is suggestive of possible involvement of the 14-3-3 proteins in the regulation of HvNHX2 function.

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The present paper deals with the study of the efficiency of oral use of the antioxidative drug Immugen (a complex of alpha-tocopherol, oubichinone, selenium aspartate, methionine, and soyabean phospholipids) on a rabbit model of severe alkaline-induced corneal burn. The investigations have indicated that addition of Immugen to the rabbit feed exerts a significant positive effect on the parameters of the local antioxidative system of the eye and causes an increase in the activity of superoxide dismutase and catalase, and, on day 14, in antioxidative activity. The early experimental periods were marked by a slight rise in the frequency of deep corneal ulcerations. Moreover, the long-term clinical effect of use of Immugen appears as a significant increase in the area of the transparency-preserving affected cornea. The findings suggest that the antioxidants can show their optimal effect in the complex therapy for burn processes, including the use of proteinase inhibitors.

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Long-standing cholestatic syndrome (LSCS) was diagnosed in 41 patients with hepatitis A and hepatitis A plus chronic persistent hepatitis B (HA + CPHB). Some patients had a cholestatic form of the disease. Morphological and morphometric liver parameters were measured at the height of icterus in 74 patients. It was found that cholestatic syndrome in patients with HA and HA = CPHB is related to reparative regeneration which always has a favourable outcome.

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Taking the binding of fusicoccin to plasma membranes as an indicator of complex formation between the 14-3-3 dimer and H+-ATPase, we assessed the effect of osmotic stress on the interaction of these proteins in suspension-cultured cells of sugar beet (Beta vulgaris L.). An increase in osmolarity of the cell incubation medium, accompanied by a decrease in turgor, was found to activate the H+ efflux 5-fold. The same increment was observed in the number of high-affinity fusicoccin-binding sites in isolated plasma membranes: the 14-3-3 content in the membranes increased 2- to 3-fold, while the H+-ATPase activity changed only slightly. The data obtained indicate that osmotic regulation of H+-ATPase in the plant plasma membrane is achieved via modulation of the coupling between H+ transport and ATP hydrolysis, and that such regulation involves 14-3-3 proteins.

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All higher plants possess highly specific binding sites for fusicoccin, a metabolite of the fungus Fusicoccum amygdali Del. These sites are harboured in the plasma membranes and formed by a 14-3-3 protein dimer associated with the C-terminal autoinhibitory domain of H+-ATPase. We considered the fusicoccin binding to plasma membranes to be an indicator of complexation between the 14-3-3 dimer and H+-ATPase, we assessed the effect of cold stress on the interaction of these proteins in suspension-cultured sugar beet cells and protoplasts derived from these cells. In both objects, upon lowering the temperature to 0-4 degrees C, a portion of the cytoplasmic 14-3-3 proteins became associated with the plasma membrane, which showed an increasing amount of ATPase/14-3-3 complexes and enhanced ATPase activity. Association between ATPase and 14-3-3 resulted in a several-fold rise in the H+ efflux from protoplasts and intact cells. We suppose that regulation of the H+ pumping under changing external conditions may be based on the interaction between H+-ATPase and the 14-3-3 proteins.

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Experiments aimed at testing the effect of Ca2+ on heat shock-induced changes in protein synthesis of cultured sugar beet cells were performed. Heat shock inhibits the synthesis of non-heat shock proteins (non-HSPs) and promotes the synthesis of a set of HSPs. Extracellular Ca2+ appeared to be strictly required for the synthesis of non-HSPs. Calcium was found to differentially exert its effect on the HSP synthesis: calcium induced (96 and 76 kDa), stimulated (94, 67, 58, 52, 32, 30, 26 and 22 kDa) or did not influence (82, 17 kDa) the de novo production of various HSPs. Cell injury increased if the cells were exposed to high temperature in a Ca(2+)-deficient medium. Calcium supplement to Ca(2+)-depleted cells resulted in the recovery of HSP synthesis and reduced cell injury by heat shock.

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On sugar beet protoplasts that carry two types of fusicoccin-binding sites, a pH downshift in a physiological range (7.0-6.6) markedly enhanced the efficiency of fusicoccin (FC) binding, mainly owing to increased avidity of low-affinity FC-binding sites. This may allow the FC-binding proteins to act as pH-sensitive modulators of cell activity, for instance, via plasma membrane H+-ATPase or potassium channels.

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The NF-kappaB/c-Rel proteins are a family of evolutionarily conserved transcription factors activated during development that in the adult, mediate many processes including the immune response. A high degree of sequence similarity is shared between the NF-kappaB/c-Rel family of transcription factors and the Drosophila Dorsal protein as well as between its cytoplasmic inhibitor, IkappaBalpha, and the Drosophila Cactus protein. Genetic analyses of Dorsal have defined components of a signaling pathway for Dorsal activation, including a serine/threonine kinase, Pelle, placed upstream of Dorsal and Cactus. We demonstrate that this pathway is likely to be conserved in mammals by the isolation of a cDNA that encodes a novel mouse protein highly related to Pelle, mPLK (mouse Pelle-like protein kinase). Expression of mPLK mRNA is developmentally regulated in the mouse and in adult tissue mPLK expression is greatest in the liver, a tissue that expresses a high level of NF-kappaB. Recombinant mPLK produced in bacteria is a protein kinase capable of autophosphorylating and phosphorylating IkappaBalpha.

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Clinical and morphological characteristics were studied for a course of acute viral hepatitis A and delta with long-term cholestatic syndrome in asymptomatic carriers of HBsAg. 149 patients with moderate disease were examined, 53 of them had long-standing cholestasis syndrome. 96 viral hepatitis patients free of cholestasis served control. It is believed that the emergence of long-term intrahepatic cholestasis may be due to the following mechanisms of sinusoid lumina as a result of a drastic enlargement of multinuclear hepatocytes, hyperplasia and hypertrophy of Kupffer's cells. impaired binding of bilirubin in zone III of hepatic acinus. In cholestatic form of hepatitis A there occurs more pronounced reduction of sinusoid volume compared to other variants of viral hepatitis run.

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The efficiency of phage DNA amplification by the method of polymerase chain reaction (PCR) with Tth DNA-polymerase was studied for optimization of PCR conditions. The effect on amplification efficiency of medium ionic strength and pH, the presence of univalent cations, detergents, gelatin, ATP, pyrophosphate, SH-reagents and ratio of concentrations of Mg and dNTPs, primers and template was studied. It has been found that a pH optimum for PCR with Tth DNA-polymerase varies from 8.5 to 9.0. An ionic strength optimum for PCR is about 0.08. The influence of univalent cations on the activity of Tth DNA-polymerase can be expressed as NH4+ greater than Na+ greater than K+. 0.01% Tween-20 significantly increases the efficiency of PCR and 0.01% gelatin inhibits it. Addition of ATP, pyrophosphate, SH-reagents to the reaction mixture did not increase the yield of PCR product. It has been also shown that for the given PCR-system an optimum Mg/dNTPs molar ratio is within the range of 1.5-2.0. An optimum concentration of each of the pair of primers for this PCR-system is about 0.3 microM. The possibility of PCR-amplification of 500-8500 b.p. DNA fragments has been demonstrated.

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Five complementing recessive mutations that exhibit increased bacterial transposon Tn5 precise excision in yeast Saccharomyces cerevisiae were obtained by ethylmethanesulfonate treatment. One of these mutations (tex1) was submitted to extensive genetic analysis. tex1 is a recessive temperature-sensitive mutation resulting in a 20-100-fold increase in Tn5 excision. It also has increased frequencies of ochre mutation reversion, of forward mutation to canavanine resistance, and loss of chromosome III or its right arm. The possible mechanism of tex1 effects is discussed.

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The collection of overlapping lys2 deletions (five in the chromosomal and seven in the plasmid LYS2 gene) is constructed in this work. The deletions overlap the whole coding region of the gene and provide the system for intragenic recombinational mapping of lys2 mutations in one of 14 controlled regions. A portion of these regions can be correlated with the regions on the physical map of LYS2. Mutations in two regions can be easily cloned. The system constructed gives the possibility for the study of intragenic and molecular specificity of mutagenesis.

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Electron microscopy used for examinations of small intestine suspensions of piglets in the prenatal and postnatal periods allowed influenza virions to be identified in virus population. An attempt was made to preserve the discovered population in alternating animal--cell culture--animal passages. Serological examinations of the swine herd confirmed the circulation of influenza viruses in the herd.

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It has been found that at pH 7.4 and 2 mg/ml protein, bovine heart mitochondrial creatine kinase (CKm) contains less than 10% of the dimer. The constant for the CKm octamer dissociation into dimers, Kd, in the presence of substrates forming an analog of the complex of the transient state was found to be equal to 4.9 10(-17) M3. Using this value, the experimental conditions were chosen so as to achieve a practically complete dissociation of the octamer into dimers. Evidence has been obtained suggesting that the octamer does not dissociate into dimers during the time course of the kinetic experiments; the corresponding kinetic parameters of the CKm octamer and dimer are as follows: KMgATPm = 82 microM and 42 microM; KCrm = 8.1 mM and 3.4 mM; Vf = 61 and 60 micrograms-equiv. H+ min-1 mg-1; KMgADPm = 43 microM and 17 microM, KCPm = 0.68 mM and 0.23 mM; Vr = 162 and 111 micrograms-equiv. H+ min-1 mg-1. The experimental and calculated data shed additional light on the physiological role of CKm.

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Outbred laboratory mice, pretreated with an ascites-forming stimulator and an irradiation dose of 6 Gy, can be used for the production of monoclonal antibodies. However, the passage of hybridomas in irradiated outbred mice rapidly leads to the death of the cells. The properties of antibodies obtained from ascitic fluid of outbred mice are no different from those of antibodies obtained from BALB/c mice.

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Beef heart mitochondria suspended in 0.25 M sucrose were treated with 0.3% glutaraldehyde (GA). The membranes were disintegrated by ultrasonication in 0.25 M KCl and precipitated by centrifugation. The relative amount of the membrane-bound mitochondrial creatine kinase (CKm) does not depend on the time course of membrane disruption. The enzyme is not removed by repeated washing of the pellet. It is concluded that this part of CKm is cross-linked to mitochondrial membranes. The maximum amount of the enzyme capable of cross-linking to the membrane with an increase in GA concentration or incubation time makes up to about 50% of the total CKm activity present in the mitochondria. It is concluded also that the CKm binding sites differ with respect to their environment.

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