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1.
Magn Reson Chem ; 47(2): 133-41, 2009 Feb.
Article in English | MEDLINE | ID: mdl-19012270

ABSTRACT

Cyclodextrins are used in many drug formulations since their cavities provide microenvironments where drug molecules can enter and form inclusion complexes for controlled drug delivery. Supercritical carbon dioxide (scCO(2)) is an alternative to organic solvents and a very attractive medium for the preparation of these inclusion complexes. The potential ability of triacetyl-beta-cyclodextrin (TA-beta-CD) to form inclusion complexes in addition to its high miscibility in liquid and scCO(2) could offer a chance for an economical and environmental friendly chemical processing. In this work, high-pressure NMR studies were performed in order to obtain information on the molecular structure and dynamics of TA-beta-CD in scCO(2) at 313.15 K and 20 MPa and its ability to form inclusion complexes under these conditions was studied. The influence of scCO(2) on a number of NMR spectral parameters, such as chemical shifts, spin-spin coupling constants, nuclear Overhauser effect (NOE) and spin-lattice relaxation (T(1)) has been studied. We unequivocally show for the first time structural changes of TA-beta-CD in scCO(2), like acetyl chain orientation and overall shape distortions that can affect its inclusion capability in this medium. The possibility of cavity self-closure is discussed and the results of two inclusion studies that support cavity self-closure, with the angiotensin-converting enzyme inhibitor, captopril, and the nonsteroid anti-inflammatory drug, flufenamic acid, are presented.


Subject(s)
Carbon Dioxide , Cyclodextrins/chemistry , Drug Carriers/chemistry , Magnetic Resonance Spectroscopy/methods , Pressure , Angiotensin-Converting Enzyme Inhibitors/administration & dosage , Anti-Inflammatory Agents, Non-Steroidal/administration & dosage , Captopril/administration & dosage , Flufenamic Acid/administration & dosage , Green Chemistry Technology , Molecular Structure
2.
Magn Reson Chem ; 46(4): 316-22, 2008 Apr.
Article in English | MEDLINE | ID: mdl-18306173

ABSTRACT

Solid-state (23)Na and (31)P magic-angle spinning nuclear magnetic resonance spectroscopy and X-ray crystallography have been used to study the structures of the chain metaphosphates NaCa(PO(3))(3) and NaSr(PO(3))(3). The compounds are isostructural and crystallise in space group P(-1) with the following parameters: NaCa(PO(3))(3), a = 6.711 A, b = 6.934 A, c = 7.619 A, alpha = 83.44 degrees , beta = 81.41 degrees , gamma = 82.80 degrees ; NaSr(PO(3))(3)a = 6.805 A, b = 7.133 A, c = 7.720 A and alpha = 83.71 degrees , beta = 80.48 degrees , gamma = 82.87 degrees . Both structures contain anionic metaphosphate chains of (PO(3))(n) (n) with ionic contacts to Na(+) ions in distorted octahedral sites and Ca(2+) (or Sr(2+)) in distorted dodecahedral sites. (31)P and (23)Na NMR are entirely consistent with the crystallographic data and an empirical method for assigning (31)P resonances to particular crystallographically unique P atoms is described.


Subject(s)
Calcium/chemistry , Phosphates/chemistry , Sodium/chemistry , Strontium/chemistry , Crystallography, X-Ray , Magnetic Resonance Spectroscopy/methods , Magnetic Resonance Spectroscopy/standards , Models, Molecular , Molecular Structure , Phosphorus Isotopes , Reference Standards , Sodium Isotopes , Spectrophotometry, Infrared/methods , Temperature
3.
Ter Arkh ; 79(11): 10-6, 2007.
Article in Russian | MEDLINE | ID: mdl-18219965

ABSTRACT

AIM: To study seasonal and age features of etiological structure of acute intestinal infections (AII) in the territory of the RF. MATERIAL AND METHODS: A total of 7388 AII inpatients aged from 1 day to 90 years from 7 cities (Moscow, St-Petersburg, Nizhniy Novgorod, Chelyabinsk, Tyumen, Makhachkala and Khabarovsk) of the RF participated in a trial conducted from December 2001 to September 2006 The patients were examined with diagnostic tests based on polymerase chain reaction (PCR) for detection of rotaviruses of group A (RVA), noroviruses, astroviruses, adenoviruses, salmonella, termophilic campilobacteria, shigella and enteroinvasive Escherichia coli (EIEC). RESULTS: The above agents were detected in 72% children and 52% adults. In children RVA and noroviruses occurred most frequently (29.5% and 11%, respectively). The adults carried most often salmonella (9.3%), noroviruses (8.4%), RVA (7.8%) and Schigella in combination with EIEC (7.0%). CONCLUSION: Viral agents are essential or prevailing causative agents of AII at different ages. Seasonal and age-related trends of AII morbidity are characterized.


Subject(s)
Communicable Diseases/complications , Communicable Diseases/epidemiology , Gastrointestinal Diseases/epidemiology , Gastrointestinal Diseases/microbiology , Seasons , Adolescent , Adult , Age Distribution , Aged , Aged, 80 and over , Child , Child, Preschool , Communicable Diseases/rehabilitation , Female , Gastrointestinal Diseases/virology , Hospitalization/statistics & numerical data , Humans , Infant , Infant, Newborn , Length of Stay/statistics & numerical data , Male , Middle Aged , Russia/epidemiology
4.
Bioorg Med Chem ; 7(12): 2899-904, 1999 Dec.
Article in English | MEDLINE | ID: mdl-10658594

ABSTRACT

New 6beta-cysteinesulfonamidopenicillanic acids and their sulfoxides were synthesized by sulfonylation of 6beta-aminopenicillanic acid or its (S)-sulfoxide with (R)-N-benzyloxycarbonylcysteinesulfonyl chloride ethyl ester (2a, 1b) and (R)-N-benzyloxycarbonylcysteinesulfonyl chloride benzyl ester (2a, 2b). The corresponding 6beta-cysteinesulfonamidopenicillanic acids sulfones 1c and 2c were prepared by oxidation of the sulfoxides 1b and 2b with potassium permanganate in aqueous medium. When combined with ampicillin some of the compounds reduced the minimal inhibitory concentrations of ampicillin against beta-lactamase producing strains.


Subject(s)
Penicillanic Acid/analogs & derivatives , beta-Lactamase Inhibitors , Drug Interactions , Drug Resistance, Microbial , Drug Therapy, Combination/pharmacology , Gram-Negative Bacteria/drug effects , Gram-Positive Bacteria/drug effects , Magnetic Resonance Spectroscopy , Penicillanic Acid/chemical synthesis , Penicillanic Acid/pharmacology , Structure-Activity Relationship
5.
Biokhimiia ; 55(8): 1356-61, 1990 Aug.
Article in Russian | MEDLINE | ID: mdl-2288982

ABSTRACT

The changes in the structure and RNA-polymerase activity of rat liver cell chromatin after a single injection of cycloheximide (3 mg/kg of body mass) were studied. The cycloheximide-induced fluctuations in protein synthesis rates are concomitant with episodes of drastic changes in the chromatin structure. The reorganization of the general protein structure is associated with an increase or a decrease of the RNA-polymerase II activity. The data obtained suggest that the activation-inactivation of RNA-polymerase II in cell nuclei is due to reorganization of chromatin infrastructures--from higher levels of the electron-dense chromatin package to the unfolded nucleosomes of the transcriptionally active protein.


Subject(s)
Chromatin/metabolism , Liver/metabolism , Protein Biosynthesis , Animals , Chromatin/chemistry , Cycloheximide/pharmacology , Enzyme Activation , Liver/enzymology , Macromolecular Substances , Male , Protein Conformation , RNA Polymerase II/antagonists & inhibitors , RNA Polymerase II/metabolism , Rats
6.
Biull Eksp Biol Med ; 108(9): 350-1, 1989 Sep.
Article in Russian | MEDLINE | ID: mdl-2514813

ABSTRACT

An experimental investigation of the ability of the chondroitinsulphate preparation produced from cattle tracheas, of rumalon and chonsuride to stimulate the regeneration of cutaneous coverings in case of their injury was carried out. A strength of the surgical cicatrix and its elongation at rupture in two weeks' injections of chondroitinsulphate increased in comparison with control. A stimulating effect of chondroitinsulphate to regeneration of flesh wound in case of local single action didn't differ essentially from the effect of chonsuride. In case of application of the preparations, an area of wound for the rats received chondroitinsulphate was already on the eighth day twice as less in comparison with the animals treated with chonsuride. Thus, a stimulating effect of chondroitinsulphate preparation to the regeneration of damaged cutaneous coverings by both parenteral and local administration was shown.


Subject(s)
Chondroitin Sulfates/therapeutic use , Chondroitin/analogs & derivatives , Cicatrix/drug therapy , Wound Healing/drug effects , Animals , Drug Evaluation, Preclinical , Male , Rats , Rats, Inbred Strains , Stimulation, Chemical , Time Factors , Tissue Extracts/therapeutic use
7.
Tsitologiia ; 30(12): 1487-91, 1988 Dec.
Article in Russian | MEDLINE | ID: mdl-2854674

ABSTRACT

Blood plasma, serum and its fractions containing components of different molecular masses obtained by dialysis and gradual ultrafiltration were tested for their action on the sodium currents of voltage clamped internally perfused neuroblastoma cells. Blood plasma free of platelet factor 4, serum and its fractions containing components of molecular masses more than 50 kD produced an increase in sodium channel currents and shifts in activation and inactivation curves along the voltage axis towards more negative or positive potentials, respectively. Moreover, the serum deficient in components with the molecular masses less than 50 kD produced a more prominent effect on all the parameters tested. Thus, the low-molecular fractions were suggested to exert an inhibitory activity on the stimulatory effects produced by the high-molecular components of the serum.


Subject(s)
Blood Proteins/pharmacology , Neuroblastoma/physiopathology , Plasma/physiology , Sodium Channels/drug effects , Animals , Blood Proteins/isolation & purification , Humans , Membrane Potentials/drug effects , Mice , Molecular Weight , Sodium Channels/physiology , Tumor Cells, Cultured
8.
Tsitologiia ; 30(1): 92-6, 1988 Jan.
Article in Russian | MEDLINE | ID: mdl-2833830

ABSTRACT

A study was made of the activity and heat resistance of preparations of Na, K-ATPase, Mg-ATPase and succinate dehydrogenase of the lake frog R. ridibunda caused by the heat shock of animals. A decrease in the activity and an increase in the heat resistance of all the three enzymes studied were observed. The level of individual correlations between these parameters remained unchanged. An increase in the heat resistance of Na, K-ATPase occurs at the expense of a higher threshold of its thermal inactivation without changes in the affinity of this enzyme to Na+ and K+. Under discussion is the question of the functional significance of the changes observed.


Subject(s)
Energy Metabolism , Heat Exhaustion/enzymology , Rana ridibunda/metabolism , Ranidae/metabolism , Animals , Ca(2+) Mg(2+)-ATPase/metabolism , Kidney/enzymology , Liver/enzymology , Sodium-Potassium-Exchanging ATPase/metabolism , Succinate Dehydrogenase/metabolism , Temperature
9.
Tsitologiia ; 29(1): 108-12, 1987 Jan.
Article in Russian | MEDLINE | ID: mdl-3031860

ABSTRACT

A study was made of the correlation between the levels of the activity and heat resistance of Na,K-ATPase, Mg-ATPase and succinate dehydrogenase (SDG) in Rana ridibunda. A correlation was observed between the activities of two ATPases, and between either of them and the activity of liver SDG. The correlation coefficient between the heat resistance levels was statistically significant only in SDG of liver and muscles. The question whether the criterion of T50% inactivation may be good for a comparative appraisal of the heat resistance of enzymes is under discussion.


Subject(s)
Energy Metabolism , Hot Temperature , Rana ridibunda/metabolism , Ranidae/metabolism , Animals , Ca(2+) Mg(2+)-ATPase/metabolism , Enzyme Stability , Hibernation , Kidney/enzymology , Liver/enzymology , Muscles/enzymology , Rana temporaria , Sodium-Potassium-Exchanging ATPase/metabolism , Succinate Dehydrogenase/metabolism
10.
Tsitologiia ; 28(5): 524-9, 1986 May.
Article in Russian | MEDLINE | ID: mdl-3016954

ABSTRACT

The heat resistance of SDG, Na, K-ATPase and Mg-ATPase of the grass frog was determined in January, March and May, the number of animals examined being 30-40 in either experiment. It was found that the average level of the heat resistance of the enzymes studied shows significant, often differently directed changes, which depend on the physiological state of an organism. Negligible correlation between the thermal sensitivity of different enzymes of an organism during hibernation, completely disappear during the activity state.


Subject(s)
Adenosine Triphosphatases/metabolism , Energy Metabolism , Hot Temperature , Rana temporaria/physiology , Succinate Dehydrogenase/metabolism , Animals , Ca(2+) Mg(2+)-ATPase/metabolism , Female , Hibernation , Male , Oviposition , Seasons , Sodium-Potassium-Exchanging ATPase/metabolism , Temperature
11.
Tsitologiia ; 28(4): 418-21, 1986 Apr.
Article in Russian | MEDLINE | ID: mdl-3012838

ABSTRACT

The activity of SDG, Na, K-ATPase and Mg-ATPase of the grass frog was determined in January, March and May, the number of animals examined being 30-40 in either series of experiments. In May (period of reproduction) the average activity of the above enzymes was higher than in January and March. This was observed both in males and females. A correlation between enzymatic activities of each single organism in March and May significantly increased. The role of these changes in the increase of viability of the organism is discussed.


Subject(s)
Adenosine Triphosphatases/metabolism , Energy Metabolism , Rana temporaria/physiology , Succinate Dehydrogenase/metabolism , Animals , Ca(2+) Mg(2+)-ATPase/metabolism , Female , Liver/enzymology , Male , Muscles/enzymology , Reproduction , Seasons , Sodium-Potassium-Exchanging ATPase/metabolism
12.
Tsitologiia ; 28(2): 181-5, 1986 Feb.
Article in Russian | MEDLINE | ID: mdl-3010518

ABSTRACT

The surface activity and effect of histone, sodium deoxycholate and Triton X-100 on N+,K+-ATPase have been compared. It has been found that the coefficient of surface tightness on the borderline of suspension of ATPase containing membranes/air decreases with the increase in concentrations of these agents. The enzyme activity undergoes biphasic modification increasing with lower and decreasing with higher concentrations of the agents. The effectiveness of the agents depends on the charge of their molecules. The mechanism of interaction between Na+,K+-ATPase and the above modifiers is discussed.


Subject(s)
Cell Membrane/enzymology , Sodium-Potassium-Exchanging ATPase/metabolism , Animals , Cell Membrane/drug effects , Deoxycholic Acid/pharmacology , Detergents/pharmacology , Dose-Response Relationship, Drug , Drug Interactions , Electrochemistry , Guinea Pigs , Histones/pharmacology , In Vitro Techniques , Octoxynol , Polyethylene Glycols/pharmacology , Surface Tension , Suspensions
13.
Tsitologiia ; 27(2): 230-2, 1985 Feb.
Article in Russian | MEDLINE | ID: mdl-2986329

ABSTRACT

The activity and heat resistance of succinate dehydrogenase (SDG), Na, K-ATPase and Mg-ATPase of the grass frog (39 specimens) have been determined. No correlation was found between individual levels of heat resistance both of either enzyme examined and of the same enzyme but taken from different tissues (SDG of liver and muscles). The average level of heat resistance of SDG in liver is significantly higher than that in m. gastrocnemius. A statistically significant correlation was observed between individual levels of enzyme activity in the internal organs (SDG of liver, Na, K-ATPase and Mg-ATPase of kidney). The activity of SDG of muscles does not correlate with that of either partner.


Subject(s)
Adenosine Triphosphatases/metabolism , Energy Metabolism , Hot Temperature , Sodium-Potassium-Exchanging ATPase/metabolism , Succinate Dehydrogenase/metabolism , Animals , Ca(2+) Mg(2+)-ATPase , Drug Stability , Kidney/enzymology , Liver/enzymology , Muscles/enzymology , Rana temporaria
14.
Tsitologiia ; 25(2): 210-3, 1983 Feb.
Article in Russian | MEDLINE | ID: mdl-6134364

ABSTRACT

A comparison was made between the heat resistance levels of two enzymatic preparations: the actomyosinic and the transport ATPases of two species of frogs (grass and lake frogs) differing in their thermophilia. The interspecies differences in the heat resistance were found to be 6 degrees C for the actomyosinic and 3 degrees C for the transport ATPase in favour of the more thermophilic lake frog. In both species the myosinic ATPase is more sensitive to heat than the transport one. The high heat resistance of the transport ATPase is due to a higher threshold of its sensitivity to temperature.


Subject(s)
Actomyosin/metabolism , Adenosine Triphosphate/metabolism , Hot Temperature , Rana ridibunda/metabolism , Rana temporaria/metabolism , Ranidae/metabolism , Sodium-Potassium-Exchanging ATPase/metabolism , Animals , Biological Transport , Calcium-Transporting ATPases/metabolism , Drug Stability , Species Specificity , Temperature
15.
Biull Eksp Biol Med ; 91(2): 216-8, 1981 Feb.
Article in Russian | MEDLINE | ID: mdl-7194701

ABSTRACT

Specific features of the effect of lactin and hyphotocin or their combinations on lactopoiesis were studied in experiments on female white rats being in the stage of fading lactation. In a morphological examination of the mammary gland it was discovered that changes characteristic of galactopoiesis increase under the influence of lactin are accompanied by milk delay in lactopoietic lobules. Hyphotocin that intensifies lactation increases milk secretion without inhibiting the physiological involution of the gland. Simultaneous injection of lactin and hyphotocin stimulates lactation and inhibits the morphological involution of the mammary gland.


Subject(s)
Mammary Glands, Animal/metabolism , Milk/metabolism , Oxytocin/administration & dosage , Prolactin/administration & dosage , Animals , Animals, Newborn , Drug Interactions , Female , Lactation/drug effects , Oxytocin/pharmacology , Pregnancy , Prolactin/pharmacology , Rats
17.
Mikrobiologiia ; 45: 400-5, 1976.
Article in Russian | MEDLINE | ID: mdl-1004242

ABSTRACT

The activity of ubiquinone-dependent enzyme systems was studied in mitochondrial fractions of the yeast Candida guilliermondii cultivated on the medium containing carbohydrates of hydrocarbons as a source of carbon. The activity of NADH2-oxidase and succinate-CoQ-reductase was higher in systems with mitochondrial fractions from the cells grown on the medium with n-paraffins than in mitochondrial fractions from the cells cultivated on the medium with glucose. About 30% of intracellular ubiquinone is located in the mitochondrial fraction of hydrocarbon oxidizing yeast cells; however, the activity of enzymes was stimulated upon introduction of exogeneous ubiquinones into the systems. Therefore, exogeneous ubiquinones may be involved in the electron transport chain during oxidation of reduced substrates. Both ubiquinone-dependent enzyme systems are resistant to storage.


Subject(s)
Candida/metabolism , Ubiquinone/metabolism , Candida/enzymology , Electron Transport , Glucose/metabolism , Hydrocarbons/metabolism , Mitochondria/enzymology , NADH, NADPH Oxidoreductases/metabolism , Oxidation-Reduction , Succinate Dehydrogenase/metabolism
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