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Heterologous expression in yeast of mCYP11A1 fusions with different topogenic signals of yeast mitochondrial proteins for artificial channeling to different translocases of the inner membrane was used to gain insight in the mechanism of its topogenesis in mitochondria. To ensure insertion of the CYP11A1 domain into the inner mitochondrial membrane during the process of translocation, topogenic sequences containing transmembrane segments of Bcs1p(1-83), DLD(1-72), and full-sized AAC protein were used when constructing modified forms of CYP11A1, and the Su9(1-112) addressing signal was included to stimulate membrane insertion of CYP11A1 after its translocation to the matrix. Alternatively, to promote slippage of the hybrid molecules into the matrix, the hybrid of mCYP11A1 with the precursor of steroidogenic mitochondria matrix protein adrenodoxin (preAd) was designed. The extra sequences used for intramitochondrial sorting of CYP11A1 apparently ensured predicted topology of hybrid molecules in yeast mitochondria. All of the addressing sequences, containing transmembrane domains, provided effective insertion of the hybrid proteins AAC-mCYP11A1, Bcs1p(1-83)-mCYP11A1, DLD(1-72)-mCYP11A1 and Su9(1-116)-mCYP11A1 into the inner membrane. preAd-mCYP11A1 hybrid molecules were shown to be translocated across the inner membrane and tightly associated with the membrane on its matrix side but not membrane inserted. Measuring specific activities of hybrid proteins in the mitochondrial fractions upon addition of Ad and AdR showed that the hybrids predetermined for cotranslocational insertion of CYP11A1 into the inner membrane were more active in the reaction of cholesterol side-chain cleavage than those destined for insertion on the matrix side of the IM, the Ad-mCYP11A1 hybrid demonstrating only residual enzyme activity. The data obtained reinforce the proposal that complete transfer of the polypeptide chain into the matrix is not a necessary stage in its topogenesis, but rather persistent interaction of the polypeptide chain with the membrane during the process of translocation is of importance for heme binding, folding and membrane insertion.

The conditions are studied under which stable ion acoustic envelope solitons propagating perpendicular to the magnetic field lines can exist in the ionospheric plasma. The amplitudes, frequencies, and lengths of the waves are determined. The results obtained are compared with the experimental data. It is suggested that such solitons play an important role in both the formation of an ionization front and its motion across the magnetic field and also give rise to a fluctuation precursor in explosive ionospheric experiments.

We found that inhibitors of mitochondrial respiratory chain complexes III (myxothiazol) and I (piericidin A) in some epithelial carcinoma cell lines induce transcription of the p53-responsive SESN2 gene that plays an important role in stress response and homeostatic regulation. However, the effect did not depend on p53 because i) there was no induction of p53 after the treatment with piericidin A; ii) after the treatment with myxothiazol the peak of SESN2 gene upregulation occurred as early as 5h, before the onset of p53 activation (13h); iii) a supplementation with uridine that abolishes the p53 activation in response to myxothiazol did not abrogate the induction of SESN2 transcripts; iv) in the p53 negative HCT116 p53 -/- cells SESN2 transcription could be also induced by myxothiazol. In response to the respiratory chain inhibitors we observed an induction of ATF4, the key transcription factor of the integrated stress response (ISR). We found that the induction of SESN2 transcripts could be prevented by the ISR inhibitory small molecule ISRIB. Also, by inhibiting or overexpressing ATF4 with specific shRNA or ATF4-expressing constructs, respectively, we have confirmed the role of ATF4 in the SESN2 gene upregulation induced by mitochondrial dysfunction. At a distance of 228 bp upstream from the SESN2 transcription start site we found a candidate sequence for the ATF4 binding site and confirmed its requirement for the induction of SESN2 in luciferase reporter experiments. We suggest that the upregulation of SESN2 by mitochondrial dysfunction provides a homeostatic feedback that attenuates biosynthetic processes during temporal losses of energy supply from mitochondria thereby assisting better adaptation and viability of cells in hostile environments.

Several vertical sections are investigated in the HgBr2-PbBr2-CsBr system by the methods of physicochemical analysis. Six compounds, namely, CsHg2Br5, CsHgBr3, Cs2HgBr4, CsPb2Br5, CsPbBr3, and Cs4PbBr6, are formed in the bordering binaries of the ternary system. By the results of investigation, the projection of the liquidus surface of the HgBr2-PbBr2-CsBr system on the composition triangle is constructed, and the fields of primary crystallization of nine phases are plotted, namely, HgBr2, PbBr2, CsBr, CsHg2Br5, CsHgBr3, Cs2HgBr4, CsPb2Br5, CsPbBr3, and Cs4PbBr6. An immiscibility region is found in the system. This region occupies a considerable part of the primary crystallization field of PbBr2. The coordinates of invariant points are determined, and isotherms are plotted.

Results are presented from processing the measurement data on low-frequency fluctuations from the North Star active explosive ionospheric experiment. The fluctuation precursor signal was processed by the wavelet analysis method. The structures revealed are identified as ion acoustic envelope solitons.

The main objective of this work was to investigate the temporal variability of hydrochemical parameters in two coastal regions of the Northeastern Black Sea: the Gelendzhik bay, influenced by anthropogenic activities and the Golubaya bay an open coastal region. Dissolved oxygen, biochemical oxygen demand, pH, alkalinity, phosphate, organic phosphorus, silicates, nitrates, nitrites, ammonia, organic nitrogen, oil products and heavy metals were measured. Si/P and Si/N ratios showed that the Gelendzhik bay waters were significantly enriched in nitrogen and phosphorus compounds. Unlike the Golubaya bay, phosphates were always present in the Gelendzhik bay, and development of photo-synthesis was not limited by these. Features of seasonal variability of nutrients in the Gelendzhik bay (increased concentrations and pronounced summer–autumn maximum) appeared to be a result of human impact—outflow of nutrients with shore input and recreational activities during the summer holiday season. The data obtained indicate...

Study on the morphology and morphogenesis of wing membranes in Bats has revealed some peculiarities in their structure and development. Understanding the embryogenesis of these animals, as well as attraction of data obtained on their molecular genetics and paleontology, allows one to single out some factors that could have initiated evolutionary modifications in development programs. A scenario of the key morphofunctional transformations in the forelimbs during the evolution of chiropterans is given.

The HgBr2-CsPbBr3 (1) and CsHgBr3-PbBr2 (2) joins of the HgBr2-PbBr2-CsBr system are studied using differential thermal analysis (DTA) and X-ray powder diffraction. Both joins are non-quasi-binary. The primary phase fields, joint crystallization fields, and invariant temperatures are determined along these joins. X-ray powder diffraction results validate the diagrams mapped for these joins.

The data of experimental laboratory studies into the methane sorption kinetics in samples of mineral coals of different metamorphism grade and petrographic composition are presented. Their relation to the character of gas emission from gas-saturated coal seams is considered. The dependence of the gas emission type on the size of undisturbed fragment of coal and methane diffusion coefficient is revealed.

The dimethylformamide-water system was studied by proton spin-spin relaxation (296 K) and refractometry (298 K), and the results in combination with published densimetric data (293 K) and data on the sound velocities (293 K) were used to simulate the associative equilibria. A consistent scheme of heteroassociative equilibria in the dimethylformamide-water system was suggested. The compositions of the heteroassociates were determined, and their stability constants (in the mole fraction scale), relaxation efficiency coefficients, limiting refractive indices, limiting sound velocities, and limiting densities were calculated.

A method of measuring the thermal conductivity of solid heat-insulating materials based on the integral form of Fourier's equation, obtained by an integro-interpolation method is described. The theoretical basis for the calculation formula of the method, the results of investigations of the formula using a thermal model, the circuit of a device which realizes the theoretical formula, and the accuracy and time characteristics of the proposed method are presented.

The phase diagram of the PbBr2-BaBr2 system over the entire concentration range is studied for the first time by differential thermal analysis and X-ray powder diffraction analysis. No new compounds are formed in the system. The phase diagram is represented by a continuous series of solid solutions (type I by Rooseboom’s classification). The unit cell parameters change as a linear function of composition.

Topogenesis of cytochrome p450scc, a resident protein of the inner membrane of adrenocortical mitochondria, is still obscure. In particular, little is known about the cause of its tissue specificity. In an attempt to clarify this point, we examined the process in Saccharomyces cerevisiae cells synthesizing cytochrome p450scc as its native precursor (pCYP11A1) or versions in which its N-terminal addressing presequence had been replaced with those of yeast mitochondrial proteins: CoxIV(1-25) and Su9(1-112). We found the pCYP11A1 and CoxIV(1-25)-mCYP11A1 versions to be effectively imported into yeast mitochondria and subjected to proteolytic processing. However, only minor portions of the imported proteins were incorporated into mitochondrial membranes, whereas their bulk accumulated as aggregates insoluble in 1% Triton X-100. Along with previously published data, this suggests that a distinguishing feature of the import of the CYP11A1 precursors into yeast mitochondria is their easy translocation into the matrix where the foreign proteins mainly undergo proteolysis or aggregation. The fraction of CYP11A1 that happens to be inserted into the inner mitochondrial membrane is effectively converted into the catalytically active holoenzyme. Experiments with the Su9(1-112)-mCYP11A1 construct bearing a re-export signal revealed that, after translocation of the fused protein into the matrix and its processing, the Su9(67-112) segment ensures association of the mCYP11A1 body with the inner membrane, but proper folding of the latter does not take place. Thus it can be said that the most specific stage of CYP11A1 topogenesis in adrenocortical mitochondria is its confinement and folding in the inner mitochondrial membrane. In yeast mitochondria, only an insignificant portion of the imported CYP11A1 follows this mechanism.

Generation of energy in mitochondria is subjected to physiological regulation at many levels, and its malfunction may result in mitochondrial diseases. Mitochondrial dysfunction is associated with different environmental influences or certain genetic conditions, and can be artificially induced by inhibitors acting at different steps of the mitochondrial electron transport chain (ETC). We found that a short-term (5 h) inhibition of ETC complex III with myxothiazol results in the phosphorylation of translation initiation factor eIF2α and upregulation of mRNA for the activating transcription factor 4 (ATF4) and several ATF4-regulated genes. The changes are characteristic for the adaptive integrated stress response (ISR), which is known to be triggered by unfolded proteins, nutrient and metabolic deficiency, and mitochondrial dysfunctions. However, after a prolonged incubation with myxothiazol (13–17 h), levels of ATF4 mRNA and ATF4-regulated transcripts were found substantially suppressed. The suppression was dependent on the p53 response, which is triggered by the impairment of the complex III-dependent de novo biosynthesis of pyrimidines by mitochondrial dihydroorotate dehydrogenase. The initial adaptive induction of ATF4/ISR acted to promote viability of cells by attenuating apoptosis. In contrast, the induction of p53 upon a sustained inhibition of ETC complex III produced a pro-apoptotic effect, which was additionally stimulated by the p53-mediated abrogation of the pro-survival activities of the ISR. Interestingly, a sustained inhibition of ETC complex I by piericidine did not induce the p53 response and stably maintained the pro-survival activation of ATF4/ISR. We conclude that a downregulation of mitochondrial ETC generally induces adaptive pro-survival responses, which are specifically abrogated by the suicidal p53 response triggered by the genetic risks of the pyrimidine nucleotide deficiency.

The processes of association of rhodamine‐6G molecules in aqueous solutions of polyacrylic acid are studied by spectroscopic methods. The efficiency of formation of the dimers of rhodamine 6G as a function of the concentration of the polyelectrolyte and its chain length is established. The angles between monomer molecules in the dimers of rhodamine 6G are determined for different concentrations of the polyacrylic acid and lengths of the polyion chain.

When studying the fate of mammalian apocytochrome P450scc (apo-P450scc) imported in small amounts into isolated yeast mitochondria, we found that it undergoes degradation, this process being retarded if recipient mitochondria are preloadedin vivo(to about 0.2% of total organelle protein) with a fusion protein composed of mammalian adrenodoxin reductase and adrenodoxin (AdR-Ad); in parallel we observed aggregation of apo-P450scc. These effects suggest some overload of Pim1p protease and/or mtHsp70 system by AdR-Ad, as both of them are involved in the degradation of apo-P450scc (see Savel'evet al. J. Biol. Chem.273, 20596–20602, 1998). However, under the same conditions AdR-Ad was not able to impede the import of proteins into mitochondria and the development of the mitochondrial respiratory machinery in yeast, the processes requiring the mtHsp70 system and Pim1p, respectively. These data imply that chaperones and Pim1p protease prefer their natural targets in mitochondria to imported foreign proteins.

Glass formation is studied along the CsHgBr3-CsPbBr3, Cs2HgBr4-CsPbBr3, and CsHg2Br5-CsPbBr3 sections of the HgBr2-PbBr2-CsBr ternary system. The glass formation region is demarcated. Characteristic temperatures are determined by differential thermal analysis; the ratio Tg/Tm and the Hruby factor HR for glassy samples are determined. The data are analyzed, and the most promising glass compositions along the specified sections are determined.

The results of studies of glass formation in the binary subsystems of the ternary system HgBr2-PbBr2-CsBr and in several samples whose compositions lie near ternary eutectic points of the indicated ternary systems are reported. The conditions for glass formation have been determined. The characteristic temperatures have been determined by DTA, and Tg/Tm ratios and HR factors for glassy samples calculated.

The reactions of aliphatic β-amino-β-trifluoromethylvinyl ketones with an excess of ethylenediamine at room temperature afforded the corresponding 2,3-dihydro-1H-1,4-diazepines or substituted 2-acetonyl-2-trifluoromethylimidazolidines (the latter were obtained when the approach to the carbonyl group was sterically hindered).

To analyze protein degradation in mitochondria and the role of molecular chaperone proteins in this process, bovine apocytochrome P450scc was employed as a model protein. When imported into isolated yeast mitochondria, P450scc was mislocalized to the matrix and rapidly degraded. This proteolytic breakdown was mediated by the ATP-dependent PIM1 protease, a Lon-like protease in the mitochondrial matrix, in cooperation with the mtHsp70 system. In addition, a derivative of P450scc was studied to which a heterologous transmembrane region was fused at the amino terminus. This protein became anchored to the inner membrane upon import and was degraded by the membrane-embedded, ATP-dependent m-AAA protease. Again, degradation depended on the mtHsp70 system; it was inhibited at non-permissive temperature in mitochondria carrying temperature-sensitive mutant forms of Ssc1p, Mdj1p, or Mge1p. These results demonstrate overlapping substrate specificities of PIM1 and them-AAA protease, and they assign a central role to the mtHsp70 system during the degradation of misfolded polypeptides by both proteases.

Physically transparent cornea, lens, and vitreous body are not transparent from histophysiological viewpoint and hence, cannot directly transmit light to the retina. The lens forms from two primordia in the course of the eye development: ectodermal (for capsular epithelium) and neuroglia (for lenticular stroma). These data suggest that the neuroglia migrating from the internal leaflet of the ocular goblet is a source of stromal fibroblasts of the corneal proper substance and also presents the fibroblast differons in the human ocular vitreous body and in the lenticular posterior pole. The common source in the development of the stroma of the transparent structures of the eye is explained and confirmed by the fact that the cornea, lens, vitreous body, and the retinal and brain neuroglia contain special proteins common for all these structures, crystallins. The structural relationship and origin of fibroblasts of the transparent ocular media underlie the identical functions of crystallin production; the physical and chemical characteristics of crystallins prevent the diffusion of light and cumulate it in one direction. In addition, our data on the neuroglial origin of the lenticular stroma suggest that the lenticular cells can act as Muller's glia, regulating the transformed energy flow. Hence, the fibers and stromal cells of the cornea, lens, vitreous body, and retinal glia can serve as components of the universal conduction system perceiving light, transforming it into another type of energy (presumably into electromagnetic waves or some motor pulse), and only then sending it to the photosensor cells. As a result, we have one-way light conduction due to stromal cells of transparent eye structures and inability of the retina to identify these cells. We therefore conclude that the cells located in front of the retina are invisible for the photoreceptors, because they conduct stimulation being not transparent in the physical sense, but just physiologically. We see only what this unique conduction system allows us to see.

Transgenic Saccharomyces cerevisiae yeast strains were constructed which express CYP2D6 and CYP3A4 genes under control of an artificial promoter. When added to the growth medium, sparteine, a substrate for CYP2D6, was shown to increase the content of this cytochrome P450 isoform in yeast cells. No such increase was observed when a proteinase-deficient yeast mutant was used as a parent strain. Nifedipine, a substrate for CYP3A4, failed to affect the level of CYP3A4 expression even in wild yeast cells. These results suggest that expression of CYP2D6 in human liver can at least partially be controlled post-transcriptionally by its inductors while for CYP3A4 such a mechanism is hardly possible.

The formamide-water system has been studied by the proton spin-spin relaxation method. The compositions of the resulting heterosolvates have been determined along with the stability constants on the mole fraction scale, and the relaxation efficiency coefficients.

In order to develop a model system for studying drug metabolism, we constructed recombinant yeast strains expressing human liver cytochromes P450. A high yield of cDNA-derived CYP2D6 was obtained, due to optimization of the initiation ATG codon context. The PCR-based site-mutagenesis method was used to introduce an AAA sequence immediately before the initiation codon resulting in increased translation of the GAL10-CYC1-derived mRNA. The use of a peptidase-deficient yeast strain also helped to increase the CYP2D6 content. A P450 content of 250 +/- 30 pmol per mg of microsomal protein was achieved. HPLC analysis confirmed that heterologously expressed CYP2D6 catalysed the oxidation of debrisoquine and dextromethorphan, two prototype substrates for CYP2D6. The Km for debrisoquine 4-hydroxylase was found to be 50 microM and Vmax 7.5 pmol mg-1 min-1. Dextromethorphan O-demethylase activity in CYP2D6-containing microsomes was characterized by Km 8.5 microM and Vmax 700 pmol mg-1 min-1. Biotransformation of debrisoquine and dextromethorphan was not detected in control microsomes. Yeast synthesizing CYP2D6 represents a useful in vitro system for studying xenobiotic metabolism.

The structure of the formic acid-water system was studied by proton spin-spin relaxation at 298 K. The simplest compositions of the heterosolvates were determined.

The effect of experimental hyperlipidemia on functional activity of macrophages was studied in CBA and C57Bl/6 mice resistant and sensitive to the formation of aorta lesions, respectively. Two-month atherogenic diet increased the content of cholesterol in the serum and cells of peritoneal exudate in mice of both strains. In parallel, production of nitrites and 5'-nucleotidase activity in peritoneal macrophages increased, while parameters of phagocytosis, pinocytosis, and NBT test remained unchanged. Changes in the state of macrophages can be explained by increased cholesterol content. The absence of differences in functional activity of macrophages in CBA and C57Bl/6 mice indicates that the observed shifts are insignificant for the development of fatty streaks in the aorta.

Many patients with epilepsy receive treatment in polytherapy. Selection of antiepileptic drugs (AEDs) for the combination should be carried out in accordance with the principles of rational polytherapy, taking into account the mechanism of action, pharmacokinetic (PK) and pharmacodynamic (PD) properties of drugs. Along with levetiracetam, gabapentin, vigabatrin and pregabalin, lacosamide (LCM) shows superior PK profile in rating of all AED and can be combined with any of them. The goal of this study was to evaluate efficacy and tolerability of LCM in patients with uncontrolled partial onset seizures (POS) in routine clinical practice.181 patient's charts from 14 sites in Russia have been analyzed in retrospective manner. Patients 16 years old and older with POS with or without secondary generalization were included. Documented observation period of up to 12 months after initiation or until discontinuation of LCM therapy. Primary effectiveness variables was retention at Observational Point 3 (approximately 12 months). Other variables were: percentage change from historical baseline in seizure frequency, 50% and 75% treatment response and seizure-free status at the Observational Points 1, 2 and 3 (approximately 3, 6 and 12 months) and incidence and reason of treatment discontinuation.retention rate was high with 89.5% after 12-month observation. The development of seizure frequency showed a continuous decrease in terms of 50%, 75% treatment respond rates and seizure free status. A total of 5 adverse drug reactions leading to discontinuation of LCM therapy were recorded in 5 of 181 patients (2.8%) during the observation period. The high retention rate observed in this retrospective chart review is assumed to indicate a good tolerability and effectiveness of an adjunctive LCM treatment in patients with uncontrolled partial epilepsy in Russia.Цель исследования. Оценка эффективности и переносимости лакосамида (ЛКМ) у пациентов с неконтролируемой фокальной эпилепсией в условиях реальной клинической практики. Материал и методы. Ретроспективно проанализированы медицинские карты 181 пациента в возрасте от 16 лет и старше в 14 клинических центрах РФ с неконтролируемыми парциальными приступами с вторичной генерализацией или без нее. Анализируемый период составил 12 мес от начала приема ЛКМ. Первичной конечной точкой было удержание на терапии ЛКМ в течение 12 мес. Оценивались изменение частоты приступов по показателям 50, 75 и 100%, частота и причина прекращения лечения. Результаты. Уровень удержания на препарате к концу 12-го мес наблюдения составил 89,5%. Динамика частоты приступов показала постоянное снижение в течение всего анализируемого периода по показателям 50 и 75% ответа и ремиссии. За весь период наблюдения было зарегистрировано 5 нежелательных побочных реакций, потребовавших отмены ЛКМ у 5 (2,8%) пациентов. Высокий уровень удержания и низкий процент отмены лечения из-за развития нежелательных побочных реакций позволяет сделать вывод о благоприятной переносимости и хорошей эффективности ЛКМ в режиме дополнительной терапии у пациентов с неконтролируемой фокальной эпилепсией.Цель исследования. Оценка эффективности и переносимости лакосамида (ЛКМ) у пациентов с неконтролируемой фокальной эпилепсией в условиях реальной клинической практики. Материал и методы. Ретроспективно проанализированы медицинские карты 181 пациента в возрасте от 16 лет и старше в 14 клинических центрах РФ с неконтролируемыми парциальными приступами с вторичной генерализацией или без нее. Анализируемый период составил 12 мес от начала приема ЛКМ. Первичной конечной точкой было удержание на терапии ЛКМ в течение 12 мес. Оценивались изменение частоты приступов по показателям 50, 75 и 100%, частота и причина прекращения лечения. Результаты. Уровень удержания на препарате к концу 12-го мес наблюдения составил 89,5%. Динамика частоты приступов показала постоянное снижение в течение всего анализируемого периода по показателям 50 и 75% ответа и ремиссии. За весь период наблюдения было зарегистрировано 5 нежелательных побочных реакций, потребовавших отмены ЛКМ у 5 (2,8%) пациентов. Высокий уровень удержания и низкий процент отмены лечения из-за развития нежелательных побочных реакций позволяет сделать вывод о благоприятной переносимости и хорошей эффективности ЛКМ в режиме дополнительной терапии у пациентов с неконтролируемой фокальной эпилепсией.

Mammalian cytochrome P450scc (CYP11Alp) is a pseudointegral protein of the inner membrane of mitochondria with the active center exposed in the matrix. Upon import of the CYP11Alp precursor into yeast mitochondria, only a minor part was incorporated into the inner mitochondrial membrane and acquired catalytic activity (Kovaleva, I. E., Novikova, L. A., Nazarov, P. A., Grivennikov, S. I., and Luzikov, V. N. (2003) Eur. J. Biochem., 270, 222–229). The present work is an attempt to increase the efficiency of this process by substitution of the inherent N-terminal presequence of CYP11Alp by the addressing signal of D-lactate dehydrogenase (D-LD) of the yeast Saccharomyces cerevisiae. D-LD is known to be inserted into the inner membrane of mitochondria through its transmembrane domain located close to the N-terminus of the polypeptide chain in such a way that the protein globule is exposed in the intermembrane space. The hybrid protein D-LD(1–72)-mCYP11Alp synthesized in yeast cells was imported into yeast mitochondria, underwent processing, and was inserted into the inner membrane on the side of the intermembrane space. In the presence of adrenodoxin and adrenodoxin reductase, the hybrid protein exhibited cholesterol side-chain cleavage activity. Thus, CYP11Alp insertion into the inner membrane of mitochondria mediated by the D-LD topogenic signal resulted in the catalytically active mCYP11Alp domain in the hybrid protein.

The paper presents the results of field tests of a hopper wagon after carriage of mineral fertilizers, which are further to be used for grain carriage. The tests were carried out step by steps: washings from the inner surface of the hopper wagon after carriage of mineral fertilizers in order to identify chemical substances and 12 hours after its abrasive sandblasting; washings from the inner surface, air sampling for filters and into absorbable solutions after completion of wagon blowing 2 hours after dust removal and 30 days after application of an Epovin enamel. It has been concluded that most ions as components of mineral fertilizers were found in the amounts greater than the maximum acceptable concentrations on the walls and inside the hopper wagon after mechanical cleaning of its inner surface of the wagon that carries minerals, as well as its subsequent abrasive sandblasting and blowing.

The effect of experimental hyperlipidemia on functional activity of macrophages was studied in CBA and C57Bl/6 mice resistant and sensitive to the formation of aorta lesions, respectively. Two-month atherogenic diet increased the content of cholesterol in the serum and cells of peritoneal exudate in mice of both strains. In parallel, production of nitrites and 5'-nucleotidase activity in peritoneal macrophages increased, while parameters of phagocytosis, pinocytosis, and NBT test remained unchanged. Changes in the state of macrophages can be explained by increased cholesterol content. The absence of differences in functional activity of macrophages in CBA and C57Bl/6 mice indicates that the observed shifts are insignificant for the development of fatty streaks in the aorta.

It has earlier been shown that CYP11A1 (cytochrome P450scc precursor), synthesized in yeast cells, is imported into yeast mitochondria. However, in large part the foreign protein undergoes degradation or aggregates. In this work, we tried to prevent aggregation of CYP11A1 and stimulate its insertion into the mitochondrial inner membrane by substituting cholesterol (a substrate for cytochrome P450scc) for ergosterol in yeast cells. To this end, an ergosterol-deficient Saccharomyces cerevisiae mutant, growing in the presence of cholesterol and expressing a modified bovine CYP11A1 gene, was used. Under defined conditions, the mitochondrial respiratory system developed in this yeast and CYP11A1 with the CoxIV targeting presequence was imported into the mitochondria, being then proteolytically processed. However, substitution of cholesterol for ergosterol did not result in lowered aggregation of the imported CYP11A1 and its increased content in the SMP fraction. Hence, the presence of cholesterol is not instrumental in proper intramitochondrial compartmentalization and folding of CYP11A1.

Progress in emergency medicine in the prevention and liquidation of hazardous cargo-induced accidents is analyzed. The results of development of theoretical aspects, search for adequate individual protective means and methods for chemical decontamination of hazardous cargo residues are summarized.

CsZn2Br5 crystals are studied by X-ray diffraction. The compound crystallizes in the monoclinic system with the unit cell parameters a = 6.8880(12) A, b = 10.4703(19) A, c = 6.5197(9) A, β = 108.25°, V = 446.55 A3, ρcalcd = 4.960 g/cm3. Refractive indices are n p = 1.640 and n p = 1.754.

To analyze protein degradation in mitochondria and the role of molecular chaperone proteins in this process, bovine apocytochrome P450scc was employed as a model protein. When imported into isolated yeast mitochondria, P450scc was mislocalized to the matrix and rapidly degraded. This proteolytic breakdown was mediated by the ATP-dependent PIM1 protease, a Lon-like protease in the mitochondrial matrix, in cooperation with the mtHsp70 system. In addition, a derivative of P450scc was studied to which a heterologous transmembrane region was fused at the amino terminus. This protein became anchored to the inner membrane upon import and was degraded by the membrane-embedded, ATP-dependent m-AAA protease. Again, degradation depended on the mtHsp70 system; it was inhibited at non-permissive temperature in mitochondria carrying temperature-sensitive mutant forms of Ssc1p, Mdj1p, or Mge1p. These results demonstrate overlapping substrate specificities of PIM1 and the m-AAA protease, and they assign a central role to the mtHsp70 system during the degradation of misfolded polypeptides by both proteases.

In the rat placenta symplastotrophoblast the activity of glucose-6-phosphatase increased and that of Mg-adenosine-thriphosphatase and succinate dehydrogenase decreased under the influence of joint and separate action of acetone vapour and high air humidity. The activity of alkaline phosphatase is oppressed only at high humidity or in combination of high humidity and acetone.

Some aspects of formation and functioning of the cholesterol hydroxylase system were studied. A hybrid protein was synthesized in E. coli composed of the modified form of the (NADPH)adrenodoxin reductase precursor (N-terminal domain) and the shortened adrenodoxin precursor (C-terminal domain). The modified reductase precursor contained 12 extra amino acid residues at the N-terminus and the N-terminally shortened adrenodoxin precursor had 17 C-terminal amino acids of its targeting presequence. The hybrid reduced cytochrome P450scc in a reconstituted system. Thus, neither the extra 44 amino acids at the N-terminus of the reductase nor the 17 amino acid linker affected the interaction of the active sites in the hybrid protein. These modifications do not interfere with the binding of prosthetic groups and formation of the active sites of two enzymes in the E. coli cells. Modified N-terminal sequence of the hybrid does not affect its import into heterologous mitochondria.