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1.
Stomatologiia (Mosk) ; 102(6): 28-32, 2023.
Article in Russian | MEDLINE | ID: mdl-37997310

ABSTRACT

OBJECTIVE: Conducting a retrospective analysis of the indicators of orthodontic care provided in Ryazan and the Ryazan region from 1999 to 2017. MATERIAL AND METHODS: During the study, institutions providing orthodontic care were divided into three levels of dental organizations. Level 1 medical care centers provide assistance to residents of districts of the region, the results of the work of clinics located in 2 districts of the region were analyzed for the period since 2005 to 2017. Level 2 StMO includes state dental clinics and private dental clinics in the city of Ryazan, where you can get orthodontic care. The work of state structures was analyzed from 1999 to 2011 with a step of 3 years, from 2011 to 2017. - yearly. Level 3 SMEs include specialized departments of universities, where only consultative and diagnostic assistance is provided. An analysis was made of the orthodontic pathology with which the patients treated, as well as an analysis of the orthodontic equipment used for treatment during the study period. RESULTS: The prevalence of AFA among the child population of the region's districts is at the level of 80.10±0.68%, fixed equipment is used 3 times more often in level 1 SMO than in level 2 SMI, and removable equipment is used only 10-20% less often. in the SMC and levels 1 and 2, the main part of the contingent is the child population (97.7-99.1% and 67.82-0.63%, respectively), but in the region for this type of assistance, the appealability among patients over 18 years of age is 10% less than in the city. CONCLUSION: The data obtained indicate the need for changes in the structure of orthodontic care. It is required to allocate at least 2 rates of an orthodontist in each district to provide assistance to the population living in the Ryazan region.


Subject(s)
Dental Care , Child , Humans , Adolescent , Adult , Retrospective Studies
2.
Stomatologiia (Mosk) ; 101(1): 40-45, 2022.
Article in Russian | MEDLINE | ID: mdl-35184532

ABSTRACT

AIM: To assess the impact of the type of retention device on the quality of life of orthodontic patients. MATERIAL AND METHODS: 311 patients were divided into four groups according to age. At the end of active orthodontic treatment, retainers were installed. After 6 months, a questionnaire was conducted using the standard OHIP-14 questionnaire in order to identify the attitude to the equipment used, the presence or absence of relapses and satisfaction with the state of the dental system. RESULTS: The number of relapses in all groups is approximately at the same level, which indicates almost equal opportunities for retainers to retain the achieved result. There is no correlation between the convenience of using a particular type of retainer and the willingness to do so. CONCLUSION: The motivation of patients to use removable or non-removable retention devices to a certain extent depends not only on the type of retainer, but also on the age at which the treatment was performed.


Subject(s)
Orthodontic Retainers , Quality of Life , Dental Care , Humans , Orthodontic Appliance Design , Orthodontic Retainers/adverse effects , Orthodontics, Corrective , Surveys and Questionnaires
3.
Carbohydr Polym ; 229: 115558, 2020 Feb 01.
Article in English | MEDLINE | ID: mdl-31826515

ABSTRACT

Thermoresponsivity of chitosan induced by ß-glycerophosphate (GP) in diluted aqueous solutions has been first studied by high-sensitivity differential scanning calorimetry. It has been found that the GP solutions of chitosan undergo a first-order phase transition upon heating. The onset of this transition coincides with the cloud point of the system. This allows one to identify the thermoresponsivity of chitosan as a macroscopic demonstration of the phase separation transition. The transition temperature, enthalpy, heat capacity increment, and width were determined as functions of GP and chitosan concentrations, and the dielectric constant of the solvent. Based on this data, we suggested that GP binds cooperatively to the chitosan matrix at low temperatures. The standard free energy of GP binding (Δbgint= -6 ±â€¯1 kJ mol-1) was estimated from the DSC data. It was shown that the Okada-Tanaka model of cooperative hydration of polymers adequately describes the thermogram of the GP induced phase transition of chitosan.

4.
Prikl Biokhim Mikrobiol ; 52(5): 489-94, 2016.
Article in Russian | MEDLINE | ID: mdl-29513414

ABSTRACT

A method for the determination of the antimicrobial activity of chitosan with the use of organic salts for the production of pH in the range of 5.5-8.2 was studied. The double-dilution method demonstrated the effectiveness of the determination of the antimicrobial activity of chitosan samples with different molecular weights and solubilities. It was found that the antibacterial activity of chitosan samples with different molecular weights and solubilities. It was found that the antibacterial activity increased at low pH values with increasing molecular weight, but chitosan with a molecular weight of 5-6 kDa showed higher activity at neutral and slightly alkaline pH levels. Determination of the antimicrobial activity of various chitosan samples at different pH values allowed a more reliable assessment of the potential biological activity of chitosan.


Subject(s)
Anti-Bacterial Agents , Bacteria/growth & development , Chitosan , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/pharmacology , Chitosan/chemistry , Chitosan/pharmacology , Hydrogen-Ion Concentration , Molecular Weight
5.
Bioorg Khim ; 41(1): 67-73, 2015.
Article in Russian | MEDLINE | ID: mdl-26050473

ABSTRACT

Antibacterial activity of chitosan with different molecular weight at different pH values against gram-negative Klebsiella pneumoniae was studied. It was found that the dependence of inhibition activity of chitosan on its molecular weight was inversed when the medium pH was increased above 7.0. In acidic media higher molecular weight chitosan had the higher antibacterial activity was occured while and in weak alkaline media oligomeric forms of chitosan displayed the inhibition effect only. Our results showed that the antibacterial activity of chitosan against Klebsiella pneumoniae was closely connected with its polycationic nature, and was dependent on the degree of protonation of chitosan amino groups, which at the same time depended on the degree of polymerization and solution pH values.


Subject(s)
Anti-Bacterial Agents , Chitosan , Klebsiella pneumoniae/growth & development , Oligosaccharides , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/pharmacology , Chitosan/chemistry , Chitosan/pharmacology , Hydrogen-Ion Concentration , Oligosaccharides/chemistry , Oligosaccharides/pharmacology
6.
Bull Exp Biol Med ; 153(4): 550-3, 2012 Aug.
Article in English, Russian | MEDLINE | ID: mdl-22977868

ABSTRACT

We studied the effect of combined preparation on the basis of chitosan containing a bioregulator isolated from cattle serum in a concentration of 10(-10) mg/ml on healing of II-IIIa degree skin burns in mammals in vivo.


Subject(s)
Biological Factors/pharmacology , Burns/drug therapy , Chitosan/pharmacology , Salicylic Acid/pharmacology , Skin/injuries , Wound Healing/drug effects , Animals , Biological Factors/blood , Biological Factors/therapeutic use , Cattle , Chitosan/therapeutic use , Gels , Histological Techniques , Male , Rats , Rats, Wistar , Salicylic Acid/therapeutic use , Skin/drug effects , Skin/pathology , Wound Healing/physiology
8.
Prikl Biokhim Mikrobiol ; 44(1): 111-6, 2008.
Article in Russian | MEDLINE | ID: mdl-18491607

ABSTRACT

Galactomannan from seeds of Cyamopsis tetragonoloba (L.) Taub. (guar) was depolymerized using immobilized enzymatic preparation celloviridin. A set of fragments whose molecular weights varied from 12.6 to 245.6 kDa was obtained. Sulfated derivatives of components of all fractions were synthesized, in which the content of HSO3(-) groups was 48.05% +/- 2.31. All preparations exhibited anticoagulant activity, which was recorded in vitro in two tests--aIIa and aXa. The antithrombin activity (aIIa) was high (up to 65-87 U/mg) and did not depend on the molecular weight of a sulfated derivative; in the second test (aXa), the effect of molecular weight was observed. Biospecific electrophoresis allowed us to detect the ability of galactomannan sulfates to form complexes with protamine sulfate, a classic antidote to heparin.


Subject(s)
Anticoagulants/isolation & purification , Anticoagulants/pharmacology , Blood Coagulation/drug effects , Cyamopsis/chemistry , Mannans/isolation & purification , Mannans/pharmacology , Sulfates/pharmacology , Anticoagulants/chemical synthesis , Anticoagulants/metabolism , Galactose/analogs & derivatives , Glycoside Hydrolases/metabolism , Hydrolysis , Mannans/metabolism , Molecular Weight , Protamines/metabolism , Seeds/chemistry , Sulfates/chemical synthesis , Sulfates/metabolism
9.
Prikl Biokhim Mikrobiol ; 44(6): 688-93, 2008.
Article in Russian | MEDLINE | ID: mdl-19145977

ABSTRACT

A method has been developed, for incorporating macrocyclic polyene antibiotics nistatin and amphotericin B into liposomes containing phosphatidylcholine and cholesterol (7:3) or phosphatidylcholine, cholesterol, and cardiolipin (7:3:1), the membranes of which were modified with an amphiphilic polymer of N-vinylpyrrolidone, carrying one terminal n-octadecyl group and having a molecular weight of 4000 Da. The amount of antibiotics within such liposomal nanocarriers may be as high as 17-22%. It was demonstrated that the modified liposomes have sizes in the range 150-200 nm and exhibit increased long-term storage stability and increased resistance to disrupting agents (Triton X-100 or ethanol) and ultrasound. The antifungal activity of the liposomal preparations obtained exceeded that of the antibiotics not subjected to immobilization.


Subject(s)
Amphotericin B/chemistry , Antifungal Agents/chemistry , Lipids/chemistry , Nystatin/chemistry , Pyrrolidinones/chemistry , Liposomes , Octoxynol/chemistry
10.
Prikl Biokhim Mikrobiol ; 36(2): 173-7, 2000.
Article in Russian | MEDLINE | ID: mdl-10780005

ABSTRACT

Extracellular enzymes--a chitinase and a protease with molecular weights 22 and 32 kDa, respectively--were isolated from Streptomyces kurssanovii cells. After purification on modified regenerated chitin, the enzymes were virtually homogeneous according to denaturing PAGE. Both enzymes were found to degrade chitosan.


Subject(s)
Chitinases/isolation & purification , Endopeptidases/isolation & purification , Streptomyces/enzymology , Chitin/metabolism , Chitinases/biosynthesis , Chitinases/metabolism , Electrophoresis, Polyacrylamide Gel , Endopeptidases/biosynthesis , Endopeptidases/metabolism , Extracellular Space/enzymology , Hydrolysis , Molecular Weight
11.
Biotechnol Appl Biochem ; 21(2): 139-48, 1995 04.
Article in English | MEDLINE | ID: mdl-7718157

ABSTRACT

The preparation of two affinity-chromatography sorbents based on cross-linked chitin are described. Both sorbents retained selectively one of the four extracellular chitinases in the culture supernatant produced by Streptomyces kurssanovii. Chitinases with molecular masses of 42 kDa and 26 kDa were isolated in homogeneous form using one-step affinity-chromatography procedures involving either a fully N-acetylated or a partially N-acetylated cross-linked chitin-type sorbent. Two other chitinases were not selectively bound by the sorbents and, therefore, were not isolated in a homogeneous form. The affinity sorbents were shown to be stable over the period of separation and could be used repeatedly.


Subject(s)
Chitinases/isolation & purification , Chromatography, Affinity/methods , Streptomyces/enzymology , Anticholesteremic Agents , Cells, Cultured , Chitin/analogs & derivatives , Chitin/chemistry , Chitosan , Cross-Linking Reagents/chemistry , Culture Media/chemistry , Hemostatics
12.
Biotechnol Appl Biochem ; 19(2): 199-207, 1994 04.
Article in English | MEDLINE | ID: mdl-8192867

ABSTRACT

One of the four chitinases with a molecular mass of 42 kDa existing in the chitinolytic enzyme complex produced by Streptomyces kurssanovii was separated in homogeneous form using one-step affinity chromatography on cross-linked and phosphorylated chitin-type sorbents. Three other chitinases were not selectively bound by the sorbents and were not obtained in homogeneous form. The affinity sorbents were shown to be stable over the time of separation and could be used repeatedly.


Subject(s)
Chitinases/isolation & purification , Streptomyces/enzymology , Adsorption , Chromatography, Affinity , Cross-Linking Reagents , Culture Media , Electrophoresis, Polyacrylamide Gel , Phosphorylation
13.
Biotechnol Appl Biochem ; 17(2): 251-6, 1993 04.
Article in English | MEDLINE | ID: mdl-8484909

ABSTRACT

The action of a microbial chitinolytic enzyme complex from Streptomyces kurssanovii on chitosan gels with various degrees of cross-linking and on the O-derivatives of the gels was examined. The rate of digestion of the gels was shown to depend on the degree of cross-linking as well as on the size of the O-substituent, decreasing greatly with a rise in substitution.


Subject(s)
Chitin/analogs & derivatives , Multienzyme Complexes/metabolism , Streptomyces/enzymology , Chitin/metabolism , Chitosan , Cross-Linking Reagents , Gels , Kinetics
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