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The M1.Bst19I DNA-methyltransferase gene from restriction-modification system Bst19I (recognition sequence 5'-GCATC-3') in Bacillus stearothermophilus 19 has been cloned in the expressing vector pJW, that carries a tandem of thermo inducible promoters P(R)/P(L) from phage lambda. Highly purified enzyme has been isolated by chromatography on various resins from E. coli cells where it accumulates in a soluble form. Study of M1.Bst19I properties has revealed that enzyme has a temperature optimum 50 degrees C and demonstrates the maximum activity at pH 8.0. M1.Bst19I modifies adenine in sequence 5'-GCATC-3'. Kinetic parameters of M1.Bst19I DNA methylation reaction have been determined as follows: Km for lambda DNA is 0.68 +/- 0.07 microM, Km for S-adenosil-L-methionine is 2.02 +/- 0.31 microM. Catalytical constant (kcat) is 1.8 +/- 0.05 min(-1). Comparative analysis of Target Recognition Domain amino acid sequences for M1.Bst19I and others alpha-N6-DNA methyltransferases has allowed to suppose a presence of two types of the enzymes containing a triplet ATG or ATC in the recognition sequence.

Optimal conditions for DNA methylation by the M3.BstF5I enzyme from Bacillus stearothermophilus and kinetic parameters of lambda phage DNA modification and that of a number of oligonucleotide substrates are established. Comparison of M1.BstF5I and M3.BstF5I kinetic parameters revealed that with similar temperature optima and affinity for DNA, M3.BstF5I has nearly fourfold lower turnover number (0.24 min(-1)) and modifies the hemimethylated recognition site with lower efficiency under optimal conditions than the unmethylated one. In contrast to another three methylases of the BstF5I restriction-modification system, the M3.BstF5I enzyme is able to optionally modify the noncanonical 5'-GGATC-3' DNA sequence with a rate more than one order of magnitude lower than the methylation rate of the canonical 5'-GGATG-3' recognition site.

Mammalian DNA methyltransferase 1 (Dnmt1) is responsible for copying DNA methylation patterns during cell division. A number of studies demonstrate that Dnmt1 plays an important role in carcinogenesis, that causes, in particular, significant interest in searching for specific inhibitors of this enzyme. In the present study, with the purpose of design of oligonucleotide inhibitors of human Dnmt1, a number of single-, double-stranded and hairpin DNA-structures, containing canonical or modified enzyme recognition site 5'-CG were constructed on the basis of uniform 22 b sequence. It was shown, that such structural features as C:A-mismatch, phosphorothioates and hairpin are capable to incrementally increase oligonucleotide affinity to Dnmt1. The improvement of inhibitor properties were also achieved by substitution of target cytosine with 5,6-dihydro-5-azacytosine, 5-methyl-2-pyrimidinone and 6-methyl-pyrrolo-[2,3-d]-2-pyrimidinone. The concentrations of the most efficient oligonucleotides caused 50% inhibition of methylation of 1 microM conventional DNA substrate, polymer poly(dI-dC) * poly(dI-dC), were about 10(-7) M. In the equal in vitro conditions the constructed oligonucleotide inhibitors demonstrated much stronger effect compared to known inhibitors of Dnmt1, which were used as controls.

We present the full quantum mechanical expressions for the polarization differential cross sections of the photofragments produced in slow predissociation of a parent molecule via isolated rotational branches. Both radial and Coriolis nonadiabatic interactions between the molecular potential energy surfaces have been taken into account. The expressions describe the recoil angle distribution of the photofragments and the distributions of the photofragment angular momentum polarization (orientation and alignment) in terms of the anisotropy parameters of the ranks K=0,1,2. The explicit expressions for the anisotropy parameters are presented and analyzed which contain contributions from different possible photolysis mechanisms including incoherent, or coherent optical excitation of the parent molecule followed by the radial, or Coriolis nonadiabatic transitions to the dissociative states. The obtained expression for the zeroth-rank anisotropy parameter beta is valid for any molecule and for an arbitrary value of the molecular total angular momentum J. The expressions for the orientation (K=1) and alignment (K=2) anisotropy parameters are given in the high-J limit in terms of the generalized dynamical functions which were analyzed for the case of photolysis of linear/diatomic molecules. As shown, the Coriolis nonadiabatic interaction results in several new photolysis mechanisms which can play an important role in the predissociation dynamics.

The effect of free cadaverine (Cad) on its conjugates formation was analyzed in roots of the common ice plants (Mesembryanthemum crystallinum L.). It was found for the first time that Cad could induce oxidative burst in the roots of adult plants, as was evident from the sharp decrease in the content of Cad soluble or insoluble conjugates. This unusual effect was associated with the increased oxidative degradation of exogenous Cad (1mM, 1.5h) and intense H(2)O(2) production in the root cells of adult plants. Root treatment of both juvenile and adult plants with H(2)O(2) (1mM, 1.5h) reduced the content of soluble Cad conjugates and increased the content of their components, free Cad and phenols. We also found that one of the possible reasons of the negative effect of exogenous diamine on the formation of conjugated forms in adult roots was alkalization of the root apoplast at Cad addition to nutrient medium and the unusual O(2)(-) synthase function as a pH-dependent guaiacol peroxidase in the presence of a high content of H(2)O(2). This was confirmed by the data on the accumulation of O(2)(-) and enhanced superoxide dismutase activity in adult roots under treatment with Cad. It is possible that the accumulation of O(2)(-) together with H(2)O(2) was also responsible for oxidative burst, which induced a decrease in the content of Cad conjugates in adult roots of the common ice plants.

The equilibrium molecular structure and conformation of 1,5-diazabicyclo[3.1.0]hexane (DABH) has been studied by the gas-phase electron-diffraction method at 20 degrees C and quantum-chemical calculations. Three possible conformations of DABH were considered: boat, chair, and twist. According to the experimental and theoretical results, DABH exists exclusively as a boat conformation of C s symmetry at the temperature of the experiment. The MP2 calculations predict the stable chair and twist conformations to be 3.8 and 49.5 kcal mol(-1) above the boat form, respectively. The most important semi-experimental geometrical parameters of DABH (r(e), A and angle)e), deg) are (N1-N5) = 1.506(13), (N1-C6) = 1.442(2), (N1-C2) = 1.469(4), (C2-C3) = 1.524(7), (C6-N1-C2) = 114.8(8), (N5-N1-C2) = 107.7(4), (N1-C2-C3) = 106.5(9), and (C2-C3-C4) = 104.0(10). The natural bond orbital (NBO) analysis has shown that the most important stabilization factor in the boat conformation is the n(N) --> sigma*(C-C) anomeric effect. The geometry calculations and NBO analysis have been performed also for the bicyclohexane molecule.

We present the quantum mechanical expressions for the angular momentum distribution of the photofragments produced in slow predissociation. The paper is based on our recent theoretical treatment [J. Chem. Phys. 123, 034307 (2005)] of the recoil angle dependence of the photofragment multipole moments which explicitly treat the role of molecular axis rotation on the electronic angular momentum polarization of the fragments. The electronic wave function of the molecule was used in the adiabatic body frame representation. The rigorous expressions for the fragment state multipoles which have been explicitly derived from the scattering wave function formalism have been used for the case of slow predissociation where a molecule lives in the excited quasibound state much longer than a rotation period. Possible radial nonadiabatic interactions were taken into consideration. The optical excitation of a single rotational branch and the broadband incoherent excitation of all possible rotational branches have been analyzed in detail. The angular momentum polarization of the photofragments has been treated in the high-J limit. The polarization of the photofragment angular momenta predicted by the theory depends on photodissociation mechanism and can in many cases be significant.

20 elderly patients with average age of 64 +/- 0.1, who had had their atherosclerotic ischemic stroke within the period from one month till one year, have taken Simvatin for two months in the dose of 10 mg. per day. Analysis of the central hemodynamics and lipid metabolism before and after the treatment with Simvatin showed that the medication improves central hemodynamics (linear systolic velocity in common carotid and vertebral arteries increases and peripheral resistance in complicated internal carotid artery and two vertebral arteries decreases, dimension of atherosclerosis plaques and intima-media of common carotid artery decrease. Simvatin lowers the content of cholesterin, lipoprotein and fibrinogens. Positive effect of treatment with Simvatin on the cerebral hemodynamics, intensity of atherosclerotic process and lipid methabolism proves the medication to be recommended in treatment of patients with ischemic stroke in anamnesis.

Plastids have a very interesting transcription apparatus that gives us an opportunity to investigate mono- and multisubunut RNA polymerase interaction under conditions of complex biogenesis of the organelles and the necessity to coordinate the expression of genes located in different cell compartments. The last decade has been a breakthrough in the study of chloroplast RNA polymerases. The most important advances are the discovery of nucleus-encoded RNA polymerase and nuclear gene family for sigma subunits of plastid-encoded RNA polymerase, the obtaining of knockout-mutants on the subunits of plastid-encoded RNA polymerase, and the revelation of this RNA polymerase reorganization during plastid biogenesis. The hypothesis concerning labor division between two plastid RNA polymerases has been proposed. The review focuses on the analysis of modern information about organization, function and evolution of plastid RNA polymerases.

We present the quantum-mechanical expressions for the recoil angle dependence of the photofragment multipole moments which explicitly treat the role of molecular axis rotation on the electronic angular momentum polarization of the fragments. The paper generalizes the result of Siebbeles et al. [J. Chem. Phys. 100, 3610 (1994)] to the case of dissociation of rotating molecules. The electronic wave function of the molecule was used in the adiabatic body-frame representation. The obtained rigorous expressions for the fragment state multipoles have been explicitly derived from the scattering wave-function formalism and then simplified using the quasiclassical approximation in the high-J limit. Possible radial and Coriolis nonadiabatic interactions have been taken into consideration. It is shown that the rotation of the molecular axis is described by a number of rotation factors which depend on the rank of the incident-photon polarization matrix, on the dissociation mechanism, and on the classical angle of rotation of the molecular axis gamma.

Findings of the transcranial ultrasound duplex scanning method given to patients (99 patients aged from 60 to 74 years) who had had ischemic stroke in carotid territory showed that the frequency of different degree of vessel structure formation located on homolateral side to the lesion focus doesn't depend on hemispheric localization of old ischemic stroke. Combined stenoses of carotid and vertebrobasilar vessels were diagnosed twofold in patients with ischemic lesion in the left hemisphere of the brain.

Results of 376 laparoscopies for combined traumas performed during 3 years were analyzed. Characterization of the contingent of the patients and mechanisms of the traumas is given. The diagnosis was correct and exact in 100%, in 78.2% of the patients it was possible to find out the injured organ. The expedience to expand the indications to laparoscopy for combined traumas and to fulfill the operations in the shortest time after admission was stressed. A mathematical evaluation of the strategy of doctor's behavior was made for objectivization of the psychological solution of the doctor concerning the methods of treatment of patients with a combined trauma.

In various eucaryotic organisms double-stranded RNA causes effective degradation of homologous mRNA molecules by a process called RNA interference. RNA interference is a phenomenon associated with gene suppression via regulatory RNA molecules, which are common in plants, animals, and fungi. The discovery of RNA interference stimulated the development of new approaches for suppression of target gene expression, production of stable knockout cell lines and organisms, and also stimulated studies on possible intracellular functions of this phenomenon.

Hysterectomies are arbitrarily pure operations and thus require antibiotic prevention. A great risk for postoperative infections is particularly high after Wertheim's operation. This study evaluated the efficiency of infection prevention in 19 cancer gynecological patients by using the antibiotic augmentin (amoxicillin/clavulanic acid). The first dose was administered 30 minutes before surgery in order to achieve the maximum drug concentration in blood and tissue at surgery. There was no wound suppuration. One patient (5.3%) undergone Werthein's operation was diagnosed to have retroperitoneal hematoma suppuration. One more patient (5.3%) had fever of unknown genesis. Urinary infections that are not considered to be a sign of inefficiency of antibiotic prevention and that were due to long-term catheter placement developed in 4 (21.1%) of the 19 patients. The postoperative period was smooth in 14 (73.7%) of the 19 patients. The perioperative Augumentin administration regimen used by the authors was easy-to-use and beneficial and the drug shows a low toxicity so it may be used for antibiotic prevention in cancer gynecological patients.

A residual tumor after primary cytoreductive surgery is one of the most important factors of survival of patient with advanced ovarian cancer. Maximal cytoreduction can be achieved by different ways. We studied results of extended, combined and standard operations on patients treated in the Russian Cancer Research Center of the Russian Academy of Medical Sciences in 1989-1999. It was found that only optimal cytoreduction resulted in the absence of recurrences and better overall survival of the patients independent of the operation type (extended, combined or standard).

Frequency of postoperation complications at oncological patients deviates in the range from 10 to 70 per cent. The highest frequency of infectious complications is registered after extended and complex operations (cervical carcinoma, cancer of vulva, ovarian cancer). The most frequent aerobic pathogens in oncology are enterococci, staphylococci and streptococci, in the case of urinary tract operations--enterococci and Erscherichia coli. Perioperation prophylaxis with amoxycillin/clavulanate (Augmentin) effective against this microorganisms and also against anaerobic bacteria (usual pathogens of post operation infections in oncogynecology) resulted with lower frequency of wound infections. Demonstrated prophylaxy efficacy was more potent than that of cefotaxime (p < 0.05) or when compared to results of other antibiotics administration after operations only.

We have observed shot noise in the hopping conduction of two-dimensional carriers confined in a p-type SiGe quantum well at a temperature of 4 K. Moreover, shot noise is suppressed relative to its "classical" value 2eI by an amount that depends on the length of the sample and the carrier density. We have found a suppression factor to the classical value of about one-half for a 2 &mgr;m long sample, and of one-fifth for a 5 &mgr;m sample. In each case, the factor decreased slightly as the density increased toward the insulator-metal transition. We explain these results in terms of the characteristic length ( approximately 1 &mgr;m in our case) of the inherent inhomogeneity of hopping transport, obtained from percolation theory.

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.

The paper deals with the data on treatment of 63 patients with serous borderline tumors of the ovary (SBTO). Mean age was 40.2 years. The study included 30 patients (47.6%) with stage IA tumor, 15 (23.8%)--IB, 4 (6.3%)--II and 14 (22.2%)--stage III. Relapse frequency was 14.3%, irrespective of stage and method of therapy. Surgery was given to 18 patients (28.6%), combined therapy--by 45 (71.4%). Recurrent tumor was recorded after surgery in 2 (3.2%) and in 7 (14.8%) after combined therapy. Generally, surgery is the main treatment received by patients with SBTO. Adjuvant chemotherapy was not followed by decrease in relapse rates.

The data on treatment of 50 patients with endometrial stromal sarcoma (Ess) are discussed. Mean age-46.5 years. The group included 28 patients with stage I tumor, 7-stage II, 8-stage III and 7-stage IV. The end results of surgical, combined and complex treatment were followed up in 45 cases. Surgery was given to 24 and combined and complex therapy-to 21 patients. Five- and ten-year survival was 55.6 and 26.7, respectively, whatever mode of therapy and stage.

Outpatient treatment of syphilis was given to 250 patients. All of them received extencilline (benzathine penicillin G) in intramuscular injections. One injection of the drug (2400000 U) was administered for primary seronegative syphilis (15 cases) and for prevention (65 subjects). Two injections with 7-day interval were carried out in the dose 2400000 U for primary seropositive (58 cases), secondary early (14 cases) and recurrent syphilis (36 cases). Patients with secondary recurrent syphilis whose body mass exceeded 85 kg (55 cases) and subjects with latent disease (72 cases) received 3 injections in 7-day intervals. Extencilline proved a potent antisyphilis tool able to rapidly eliminate clinical symptoms of the disease and to promote making serological reactions negative. Extencilline activity is superior to that of bicillin and water-soluble penicillin. Treponema pallidum escape from syphilid surface within 7 treatment hours, on the average. Extencilline is worthy of being used among most effective drugs in outpatient treatment of early syphilis.

Nineteen patients with acute pancreatitis were examined for the activity of LDH, NADH-tetrazolium oxidoreductase, acid phosphatase, the content of calcium salts, cAMP and cGMP in biopsy tissue of the pancreas; pancreatic enzymes and bicarbonates in the duodenal contents and pancreatic juice. The activity of enzymes participating in oxidative metabolism in epithelial cells of the intact pancreas appeared elevated. During the development of destructive changes in the pancreatic parenchyma, the processes of intracellular oxidation get inhibited, the enzymes go out into the intercellular space, calcium transport gets impaired, and acid phosphatase is activated. It has been found that in acute destructive pancreatitis, primarily impaired are epithelial cells of the islets, followed by the impairment of the epithelium of the acini and at the last moment of that of the excretory ducts. The data obtained enable one to regard cyclonucleotides, calcium, pancreatic enzymes and lysosomal hydrolases as pathogenetic elements of acute pancreatitis.

The action of different preparations of interferon on Legionella strains has been studied in vivo and in vitro. The preparations of leukinferon at a concentration of 500 international units (I.U.) and reaferon at a concentration of 10,000 I.U. have been found to produce an inhibiting effect on Legionella strains in vitro, in a medium with carbon-yeast agar. Leukinferon at a concentration of 125 I.U. suppresses the growth of L. pneumophila also in a liquid medium. The preparation of leukinferon at a minimal concentration of 100 I.U. has been found to suppress the development of lethal infection in chick embryos infected with L. pneumophila strain Philadelphia 1.

Altogether 25 patients with peptic ulcer and 26 patients with chronic pancreatitis were examined for gastric and pancreatic secretion. Histamine dihydrochloride (0.008-0.024 mg/kg) was employed to stimulate gastric secretion whereas cholecystokinin (2U/kg/h) and calcium gluconate (16 mg/kg) were used to stimulate pancreatic secretion. Lidocain (1.2 mg/kg), a blocker of Ca2+-channels, and lithium hydroxybutyrate (12 mg/kg), a blocker of phosphatidylinositol transformations, were employed for suppression of gastric and pancreatic secretion. The content of HCl, pepsinogen, fucose, cAMP and cGMP was measured in gastric juice, that of bicarbonates, amylase, lipase, trypsin, cAMP and cGMP in pancreatic juice. It has been shown that mechanisms dependent on cAMP and on extra- and intracellular Ca2+ are involved in the initiation and maintenance of gastric and pancreatic secretion. However, the contribution of those mechanisms is different as applied to the regulation of ions and enzymes, on the one hand, and to various enzymes, on the other.