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1.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Volova T.G., Vasil'ev A.D., Zeer E.P., Petrakovskaia E.A., Falaleev O.V.
Заглавие : Study of molecular structure of polyhydroxybutyrate-a termoplastic anddegradable biopolymer
Место публикации : Biofizika. - 2000. - Vol. 45, Is. 3. - С. 445-451. - ISSN 00063029 (ISSN)
Ключевые слова (''Своб.индексиров.''): carbon--hydroxybutyric acid--polyester--alcaligenes--article--chemistry--crystallization--alcaligenes--carbon--crystallization--hydroxybutyrates--polyesters
Аннотация: The molecular structure of polyhydroxybutyrate from hydrogen-oxidizing bacteria Alcaligenes eutrophus was studied by X-ray diffraction analysis. It was shown that the degree of crystallinity of various samples depends little on the conditions of their preparation and is equal to 0.62-0.76. The molecular structure of solid samples and solution of polyhydroxybutyrate in chloroform were studied by the NMR and EPR methods. The conclusion is made that the molecular structure of polyhydroxybutyrate does not depend on the features of the strain and conditions of carbon nutrition of microorganisms producing polyhydroxybutyrate. Defects induced by gamma-radiation in polyhydroxybutyrate were studied. Free radicals were isolated, and their structure was decoded.
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2.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Shishatskaya E.I., Eremeev A.V., Gitel'zon I.I., Setkov N.A., Volova T.G.
Заглавие : Cytotoxicity of polyhydroxyalkanoates in animal cell cultures.
Место публикации : Doklady Biological Sciences. - 2000. - Vol. 374, Is. 1-6. - С. 539-542. - ISSN 00124966 (ISSN)
Ключевые слова (''Своб.индексиров.''): dna--hydroxybutyric acid--poly(3 hydroxybutyrate) co (3 hydroxyvalerate)--poly(3 hydroxybutyric acid)--poly(3-hydroxybutyrate)-co-(3-hydroxyvalerate)--poly-beta-hydroxybutyrate--polyester--rna--thymidine--uridine--animal--article--biosynthesis--cell division--cell strain 3t3--cell survival--cytology--drug effect--liver--liver cell--metabolism--mouse--vascular endothelium--3t3 cells--animals--cell division--cell survival--dna--endothelium, vascular--hepatocytes--hydroxybutyrates--liver--mice--polyesters--rna--thymidine--uridine
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3.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Volova T.G., Kalacheva G.S., Altukhova O.V.
Заглавие : The autotrophic synthesis of polyhydroxyalkanoate by alcaligenes eutrophus in the presence of carbon monoxide
Место публикации : Mikrobiologiya. - 2001. - Vol. 70, Is. 6. - С. 745-752. - ISSN 00263656 (ISSN)
Ключевые слова (''Своб.индексиров.''): co inhibition--hydrogen-oxidizing bacteria--polyhydroxyalkanoates (phas)--synthesis--alkane--carbon monoxide--fatty acid--hydroxyacid--lipid--nitrogen--polyester--article--chemistry--culture medium--drug antagonism--growth, development and aging--mass spectrometry--metabolism--wautersia eutropha--alkanes--carbon monoxide--culture media--cupriavidus necator--fatty acids--hydroxy acids--lipids--mass spectrometry--nitrogen--polyesters
Аннотация: The CO-resistant strain B5786 of the hydrogen-oxidizing bacterium Alcaligenes eutrophus was found to be able to synthesize polyhydroxyalkanoates (PHAs) under the conditions of growth limitation by nitrogen deficiency (the factor that promotes PHA synthesis) and growth inhibition by carbon monoxide. The gas mixtures that contained from 5 to 20 vol % CO did not inhibit the key enzymes of PHA synthesis-?-ketothiolase, acetoacetyl-CoA reductase, hydroxybutyrate dehydrogenase, and PHA synthase. In the presence of CO, cells accumulated up to 70-75 wt % PHA (with respect to the dry biomass) without any noticeable increase in the consumption of the gas substrate. Chromatographic-mass spectrometric analysis showed that the PHA synthesized by A. eutrophus is a copolymer containing more than 99 mol % ?-hydroxybutyrate and trace amounts of ?-hydroxyvalerate. The PHA synthesized under the conditions described did not differ from that synthesized by A. eutrophus cells from electrolytic hydrogen.
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4.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Volova T.G., Kalacheva G.S., Altukhova O.V.
Заглавие : Autotrophic synthesis of polyhydroxyalkanoates by the bacteria Ralstonia eutropha in the presence of carbon monoxide
Место публикации : Applied Microbiology and Biotechnology. - 2002. - Vol. 58, Is. 5. - С. 675-678. - ISSN 01757598 (ISSN) , DOI 10.1007/s00253-002-0941-8
Ключевые слова (''Своб.индексиров.''): 3 hydroxybutyric acid--acetoacetyl coenzyme a reductase--acetyl coenzyme a acyltransferase--beta hydroxyvalerate--butyrate dehydrogenase--carbon monoxide--electrolyte--hydrogen--oxidoreductase--poly(3 hydroxybutyric acid)--poly(3 hydroxybutyric acid)synthase--polyhydroxyalkanoic acid--polymer--unclassified drug--valeric acid--bacterium--article--autotrophy--bacterial growth--bacterial strain--biomass production--controlled study--crystallization--enzyme activity--molecular weight--nonhuman--synthesis--temperature--wautersia eutropha--carbon monoxide--culture media--cupriavidus necator--fatty acids--lipids--polyesters--bacteria (microorganisms)--negibacteria--ralstonia--wautersia eutropha
Аннотация: It has been found that the carbon monoxide (CO)-resistant strain of the hydrogen bacteria Ralstonia eutropha B5786 is able to synthesise polyhydroxy-alkanoates (PHAs) in the presence of CO under autotrophic conditions. This strain, grown on model gas mixtures containing 5-25% CO (v/v), accumulates up to 70-75% (of absolutely dry matter) PHA, without significant variation in the yield coefficient on hydrogen. No suppression of the activities of the key enzymes of PHA synthesis (?-ketothiolase, acetoacetyl-CoA-reductase, butyrate dehydrogenase and poly-3-hydroxybutyrate synthase) was recorded. The PHA synthesised is a copolymer containing mostly ?-hydroxybutyrate (more than 99 mol%) with trace amounts of ?-hydroxyvalerate. The investigated properties of the polymer (molecular weight, crystallinity, temperature characteristics) do not differ from those of the polymer synthesised on electrolytic hydrogen.
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5.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Volova T.G., Voinov N.A.
Заглавие : Kinetic parameters of a culture of the hydrogen-oxidizing Ralstonia eutropha, grown under the regimen of biosynthesis of polyhydroxybutyrate
Место публикации : Prikladnaia biokhimiia i mikrobiologiia. - 2003. - Vol. 39, Is. 2. - С. 189-193. - ISSN 05551099 (ISSN)
Ключевые слова (''Своб.индексиров.''): hydrogen--hydroxybutyric acid--polyester--article--culture medium--enzyme specificity--growth, development and aging--kinetics--metabolism--oxidation reduction reaction--temperature--wautersia eutropha--culture media--cupriavidus necator--hydrogen--hydroxybutyrates--kinetics--oxidation-reduction--polyesters--substrate specificity--temperature
Аннотация: Kinetic parameters of a culture of the hydrogen-oxidizing bacterium Ralstonia eutropha, grown on a gas substrate under the conditions favoring autotrophic biosynthesis of polyhydroxybutyrate, were studied. The following parameters, making it possible to control and optimize the process in industrial situations, were determined: specific rate of substrate consumption, physical properties of culture medium, and coefficients of heat emission and mass transfer.
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6.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Sevastianov V.I., Perova N.V., Shishatskaya E.I., Kalacheva G.S., Volova T.G.
Заглавие : Production of purified polyhydroxyalkanoates (PHAs) for applications in contact with blood
Место публикации : Journal of Biomaterials Science, Polymer Edition. - 2003. - Vol. 14, Is. 10. - С. 1029-1042. - ISSN 09205063 (ISSN) , DOI 10.1163/156856203769231547
Ключевые слова (''Своб.индексиров.''): ?-hydroxy acids--endotoxins--hemocompatibility--poly(hydroxybutyrate-co-hydroxyvalerate) (phbv)--polyhydroxyalkanoates (phas)--polyhydroxybutyrate (phb)--bacterium lipopolysaccharide--carbon--complement--copolymer--hydroxyacid--long chain fatty acid--poly(3 hydroxybutyric acid)--polyhydroxyalkanoic acid--valeric acid derivative--adult--article--biofilm--biotechnology--blood analysis--blood clotting--blood compatibility--cell function--chemical analysis--chemical composition--complement activation--concentration (parameters)--controlled study--gas chromatography--hemostasis--human--human cell--mass spectrometry--micromorphology--nonhuman--priority journal--purification--quantitative analysis--sampling--synthesis--thrombocyte adhesion--wautersia eutropha--biocompatible materials--blood--blood coagulation tests--chromatography, gas--complement activation--cupriavidus necator--fatty acids--humans--platelet adhesiveness--polyesters--surface properties
Аннотация: Samples of olyhydroxyalkanoates (PHAs), polyhydroxybutyrate (PHB) and copolymers poly(hydroxybutyrate-co-hydroxyvalerate) (PHBV) with 4 and 18 mol% hydroxyvalerate, synthesized by the bacteria Ralstonia eutropha B5786, were investigated. PHA films in contact with blood did not activate the hemostasis system at the level of cell response, but they did activate the coagulation system and the complement reaction. To detect biologically-active components in the PHAs, a detailed analysis of the composition of the polymers was conducted. Gas chromatography-mass spectrometry revealed long-chain fatty acids (FAs) in the tested PHAs. Their total concentration in the polymer ranged from tenths of mol% to 2-3 mol%, depending on the purification method. C16:0 constituted the largest proportion, up to 70%. Of the long-chain hydroxy acids, only ?-OH-C14:0 was detected and it did not exceed 0.06 mol%. The analysis of the hemocompatibility properties of the PHAs purified by a specialized procedure, including the quantitative and morphological estimation of platelets adherent to the surface of polymer films, the plasma recalcification time and complement activation studies, indicated that PHB and PHBV can be used in contact with blood. It has been found out that the lipopolysaccharides of bacteria producing PHAs, which contain mostly long-chain hydroxy acids, can be the factor activating the hemostasis systems. Thus, the technology of PHA purification must satisfy rather stringent specific requirements.
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7.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Sevastianov V.I., Perova N.V., Shishatskaya E.I., Kalacheva G.S., Volova T.G.
Заглавие : Production of purified polyhydroxyalkanoates (PHAs) for applications in contact with blood
Колич.характеристики :14 с
Место публикации : J. Biomater. Sci.-Polym. Ed.: VSP BV, 2003. - Vol. 14, Is. 10. - P1029-1042. - ISSN 0920-5063, DOI 10.1163/156856203769231547
Примечания : Cited References: 34
Предметные рубрики: BIODEGRADABLE POLYESTERS
POLYMERS
Ключевые слова (''Своб.индексиров.''): polyhydroxyalkanoates (phas)--polyhydroxybutyrate (phb)--poly(hydroxybutyrate-co-hydroxyvalerate) (phbv)--endotoxins--beta-hydroxy acids--hemocompatibility
Аннотация: Samples of olyhydroxyalkanoates (PHAs), polyhydroxybutyrate (PHB) and copolymers poly(hydroxybutyrate-co-hydroxyvalerate) (PHBV) with 4 and 18 mol% hydroxyvalerate, synthesized by the bacteria Ralstonia eutropha B5786, were investigated. PHA films in contact with blood did not activate the hemostasis system at the level of cell response, but they did activate the coagulation system and the complement reaction. To detect biologically-active components in the PHAs, a detailed analysis of the composition of the polymers was conducted. Gas chromatography-mass spectrometry revealed long-chain fatty acids (FAs) in the tested PHAs. Their total concentration in the polymer ranged from tenths of mol% to 2-3 mol%, depending on the purification method. C-16:0 constituted the largest proportion, up to 70%. Of the long-chain hydroxy acids, only beta-OH-C-14:0 was detected and it did not exceed 0.06 mol%. The analysis of the hemocompatibility properties of the PHAs purified by a specialized procedure, including the quantitative and morphological estimation of platelets adherent to the surface of polymer films, the plasma recalcification time and complement activation studies, indicated that PHB and PHBV can be used in contact with blood. It has been found out that the lipopolysaccharides of bacteria producing PHAs, which contain mostly long-chain hydroxy acids, can be the factor activating the hemostasis systems. Thus, the technology of PHA purification must satisfy rather stringent specific requirements.
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8.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Volova T..., Shishatskaya E..., Sevastianov V..., Efremov S..., Mogilnaya O...
Заглавие : Results of biomedical investigations of PHB and PHB/PHV fibers
Колич.характеристики :9 с
Место публикации : Biochem. Eng. J.: ELSEVIER SCIENCE SA, 2003. - Vol. 16, Is. 2. - P125-133. - ISSN 1369-703X, DOI 10.1016/S1369-703X(03)00038-X
Примечания : Cited References: 20
Предметные рубрики: POLYHYDROXYALKANOATES
POLYESTERS
POLYMERS
Ключевые слова (''Своб.индексиров.''): polyhydroxyalkanoates (phas)--poly-3-hydroxybutyrate (phb)--poly-3-hydroxybutyrate-co-poly-3-hydroxyvalerate (phb/phv)--fibers--implants--biocompatibility--tissue reaction
Аннотация: The paper presents the results of biomedical investigations of sutures made of polyhydroxyalkanoates (PHAs) of two types (poly-3-hydroxybutyrate (PHB) and poly-3-hydroxybutyrate-co-poly-3-hydroxyvalerate (PHB/PHV)), synthesized by the bacteria Ralstonia eutropha B 5786 in the experiment on test animals in vivo, in comparison with silk and catgut sutures. PHB and PHB/PHV (PHBV) implants produced no adverse effect on physiological, biochemical and functional parameters of the animals during the post-surgery period. The tested PHA sutures featured the necessary strength throughout the healing period of the muscle-fascial cuts. The reaction of tissues to the implantation of PHB and PHB/PHV fibers fitted into the usual scheme characteristic of the wound process and of the reaction to a foreign-body invasion. This reaction and the reaction of tissues to silk had the similar nature and period of inflammation, but it was much less pronounced than the reaction to catgut. The tissue response to the implantation of PHAs consisted in a short-duration (up to 2 weeks) post-traumatic inflammation and the formation of a fibrous capsule less than 200 mum thick during weeks 4-8, which in 4-6 months was reduced to 40-60 mum in the course of reverse development. There were no adverse changes, such as suppurative inflammation, necrosis, calcification, and malignization of the cicatrice, at the site of implantation of PHA filaments, unlike in the cases with silk and catgut. In the case of PHA implantation there was a typical prolonged (throughout the post-surgery monitoring period) pronounced macrophagal stage with a large number of macrophages present. The macrophages were of the phagocytic type and multinucleate giant foreign cells, with a high activity of acid phosphomonoesterase that correlated with the activity of the enzyme in blood. Throughout the period of monitoring no differences in the tissue response to the implantation of the polymer filaments of two PHA types were recorded. (C) 2003 Elsevier Science B.V. All rights reserved.
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9.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Shishatskaya E.I., Volova T.G., Puzyr A.P., Mogilnaya O.A., Efremov S.N.
Заглавие : Tissue response to the implantation of biodegradable polyhydroxyalkanoate sutures
Место публикации : Journal of Materials Science: Materials in Medicine. - 2004. - Vol. 15, Is. 6. - С. 719-728. - ISSN 09574530 (ISSN) , DOI 10.1023/B:JMSM.0000030215.49991.0d
Ключевые слова (''Своб.индексиров.''): necrosis--polymeric implants--suppurative inflammation--tissue reaction--biodegradation--calcification (biochemistry)--cells--copolymers--implants (surgical)--silk--tissue--tumors--materials science--acid phosphatase--copolymer--poly(3 hydroxybutyric acid)--polyhydroxyalkanoic acid--polyhydroxyvaleric acid--unclassified drug--animal experiment--animal model--article--biodegradable implant--blood vessel reactivity--catgut--controlled study--enzyme activity--female--giant cell--histochemistry--inflammation--macrophage--nonhuman--priority journal--rat--silk--suture--tensile strength--tissue reaction--tissue structure--wound healing--young modulus--absorbable implants--animals--female--fibrosis--foreign-body reaction--hydroxybutyrates--muscle, skeletal--polyesters--polymers--rats--rats, wistar--sutures--treatment outcome--wounds, penetrating--animalia
Аннотация: Polyhydroxyalkanoate (PHA) sutures were implanted to test animals intramuscularly, and tissue reaction was investigated and compared with the reaction to silk and catgut. Tested monofilament sutures made of PHAs of two types polyhydroxybutyrate (PHB) and a copolymer of hydroxybutyrate and hydroxyvalerate (PHV) featured the strength necessary for the healing of muscle-fascial wounds. The reaction of tissues to polymeric implants was similar to their reaction to silk and was less pronounced than the reaction to catgut; it was expressed in a transient post-traumatic inflammation (up to four weeks) and the formation of a fibrous capsule less than 200 ?m thick, which became as thin as 4060 ?m after 16 weeks, in the course of reverse development. Macrophages and foreign-body giant cells with a high activity of acid phosphatase were actively involved in this process. PHB and PHB/PHV sutures implanted intramuscularly for an extended period (up to one year) did not cause any acute vascular reaction at the site of implantation or any adverse events, such as suppurative inflammation, necrosis, calcification of the fibrous capsule or malignant tumor formation. No statistically significant differences were revealed in the tissue response to polymer sutures of the two types. Capsules around silk and catgut sutures did not become significantly thinner.
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10.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Volova T.G., Voinov N.A.
Заглавие : Study of Ralstonia eutropha culture producing polyhydroxyalkanoates on products of coal processing
Место публикации : Prikladnaia biokhimiia i mikrobiologiia. - 2004. - Vol. 40, Is. 3. - С. 296-300. - ISSN 05551099 (ISSN)
Ключевые слова (''Своб.индексиров.''): carbon monoxide--coal--polyester--antibiotic resistance--article--culture medium--enzyme specificity--gas--growth, development and aging--metabolism--microbiology--wautersia eutropha--carbon monoxide--coal--culture media--cupriavidus necator--drug resistance, microbial--gases--polyesters--substrate specificity
Аннотация: Kinetic indices of growth, polyhydroxyalkanoate (PHA) accumulation, and gas exchange have been studied in a culture of the carbon monoxide-resistant hydrogen strain Ralstonia eutropha B-5786 grown on a gaseous substrate (GS) obtained by lignite gasification. The GS was shown to be suitable for PHA production. To increase the degree of GS consumption, various modes of gas supply to the culture were tested. Based on the results, an algorithm was developed for calculating and controlling gas-exchange parameters in the PHA-accumulating culture of Ralstonia eutropha, grown on a new GS allowing high polymer yields (up to 75%) and degrees of the substrate utilization (up to 90%).
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11.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Shishatskaya E.I., Volova T.G.
Заглавие : A comparative investigation of biodegradable polyhydroxyalkanoate films as matrices for in vitro cell cultures
Место публикации : J. Mater. Sci.-Mater. Med.: KLUWER ACADEMIC PUBL, 2004. - Vol. 15, Is. 8. - С. 915-923. - 9. - ISSN 0957-4530, DOI 10.1023/B:JMSM.0000036280.98763.c1
Примечания : Cited References: 34
Предметные рубрики: DEGRADATION
POLY(3-HYDROXYBUTYRATE)
POLYESTERS
POLYMERS
Аннотация: The paper describes the production and investigation of flexible films made of high-purity polyhydroxyalkanoates (PHAs) - polyhydroxybutyrate [poly-(3HB)] and poly-3-hydroxybutyrate-co-poly-3-hydroxyvalerate [poly(3Hl3-co-3HV)], containing 4-30 mol % hydroxyvalerate. Poly(3HB-co-3HV) films have a more porous structure than poly-(3HB) films, which are more compact, but their surface properties, such as wettability and surface and interface energies, are the same. Sterilisation of the PHA films by conventional methods (heat treatment and gamma-irradiation) did not impair their strength. Cells cultured on PHA films exhibited high levels of cell adhesion. Cell morphology, protein synthesis and DNA synthesis were estimated by extent of H-3-thymidine incorporation into the animal cell cultures of various origins (fibroblasts, endothelium cells, and isolated hepatocytes) in direct contact with PHAs. The investigation showed that this material can be used to make matrices for in vitro proliferous cells. The investigated properties of poly-(3HB) and poly(3HB-co-3HV) films proved to be fundamentally similar. (C) 2004 Kluwer Academic Publishers.
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12.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Volova T.G., Plotnikov V.F., Shishatskaya E.I., Mironov P.V., Vasil'ev A.D.
Заглавие : Physicochemical properties of two-component polyhydroxyalkanoates [Poly(3HB/3HV)]
Колич.характеристики :9 с
Место публикации : Biofizika: MEZHDUNARODNAYA KNIGA, 2004. - Vol. 49, Is. 6. - P1038-1046. - ISSN 0006-3029
Примечания : Cited References: 21
Предметные рубрики: BACTERIAL POLYHYDROXYALKANOATES
POLYESTERS
Ключевые слова (''Своб.индексиров.''): polyhydroxyalkanoates--copolymers of hydroxybutyrate and hydroxyvalerate--structure--physicochemical properties
Аннотация: A series of two-component polyhydroxyalkanoates consisting of hydroxybutyrate and hydroxyvalerate monomer at different ratios were synthesized using the bacterium Ralstonia eutropha B5786. The properties of polyhydroxyalkanoates were compared with those of the homopolymer of hydroxybutyric acid by X-ray structure analysis, IR spectroscopy, differential scanning calorimetry, and viscosimetry. With an increase in the molar fraction of hydroxyvalerate, an equalization of the ratio of the crystalline and amorphous phases in the copolymer was observed. The degree of crystallinity of the polymer decreased from 70-80 to 45-50%; in the range of an increase in the hydroxyvalerate molar fraction from several to 25-30 mol %, the dependence was linear. The temperature characteristics, the melting temperature (T-m), and the degradation temperature (T-d) were lower in polyhydroxyalkanoates than in polyhydroxybutyrate, for which T-m and T-d were 168-170 and 260-265degreesC, respectively. In the copolymer, as the molar fraction of hydroxyvalerate grew, both parameters decreased. In the range of variation of monomer ratio studied, they decreased to 150-160 and 200-220degreesC, respectively. No distinct correlation between the composition of the polymer and its molecular mass was found.
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13.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Shishatskaya E.I., Volova T.G., Puzyr A.P., Mogilnaya O.A., Efremov S.N.
Заглавие : Tissue response to the implantation of biodegradable polyhydroxyalkanoate sutures
Колич.характеристики :10 с
Место публикации : J. Mater. Sci.-Mater. Med.: KLUWER ACADEMIC PUBL, 2004. - Vol. 15, Is. 6. - P719-728. - ISSN 0957-4530, DOI 10.1023/B:JMSM.0000030215.49991.0d
Примечания : Cited References: 34
Предметные рубрики: DEGRADATION
POLYESTERS
POLYMERS
FIBERS
PHB
Аннотация: Polyhydroxyalkanoate (PHA) sutures were implanted to test animals intramuscularly, and tissue reaction was investigated and compared with the reaction to silk and catgut. Tested monofilament sutures made of PHAs of two types-polyhydroxybutyrate (PHB) and a copolymer of hydroxybutyrate and hydroxyvalerate (PHV)-featured the strength necessary for the healing of muscle-fascial wounds. The reaction of tissues to polymeric implants was similar to their reaction to silk and was less pronounced than the reaction to catgut; it was expressed in a transient post-traumatic inflammation (up to four weeks) and the formation of a fibrous capsule less than 200 mum thick, which became as thin as 40-60 mum after 16 weeks, in the course of reverse development. Macrophages and foreign-body giant cells with a high activity of acid phosphatase were actively involved in this process. PHB and PHB/PHV sutures implanted intramuscularly for an extended period (up to one year) did not cause any acute vascular reaction at the site of implantation or any adverse events, such as suppurative inflammation, necrosis, calcification of the fibrous capsule or malignant tumor formation. No statistically significant differences were revealed in the tissue response to polymer sutures of the two types. Capsules around silk and catgut sutures did not become significantly thinner. (C) 2004 Kluwer Academic Publishers.
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14.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Shishatskaya E.I., Volova T.G.
Заглавие : A comparative investigation of biodegradable polyhydroxyalkanoate films as matrices for in vitro cell cultures
Колич.характеристики :9 с
Место публикации : J. Mater. Sci.-Mater. Med.: KLUWER ACADEMIC PUBL, 2004. - Vol. 15, Is. 8. - P915-923. - ISSN 0957-4530, DOI 10.1023/B:JMSM.0000036280.98763.c1
Примечания : Cited References: 34
Предметные рубрики: DEGRADATION
POLY(3-HYDROXYBUTYRATE)
POLYESTERS
POLYMERS
Аннотация: The paper describes the production and investigation of flexible films made of high-purity polyhydroxyalkanoates (PHAs) - polyhydroxybutyrate [poly-(3HB)] and poly-3-hydroxybutyrate-co-poly-3-hydroxyvalerate [poly(3Hl3-co-3HV)], containing 4-30 mol % hydroxyvalerate. Poly(3HB-co-3HV) films have a more porous structure than poly-(3HB) films, which are more compact, but their surface properties, such as wettability and surface and interface energies, are the same. Sterilisation of the PHA films by conventional methods (heat treatment and gamma-irradiation) did not impair their strength. Cells cultured on PHA films exhibited high levels of cell adhesion. Cell morphology, protein synthesis and DNA synthesis were estimated by extent of H-3-thymidine incorporation into the animal cell cultures of various origins (fibroblasts, endothelium cells, and isolated hepatocytes) in direct contact with PHAs. The investigation showed that this material can be used to make matrices for in vitro proliferous cells. The investigated properties of poly-(3HB) and poly(3HB-co-3HV) films proved to be fundamentally similar. (C) 2004 Kluwer Academic Publishers.
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15.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Shishatskaya E.I., Volova T.G., Gordeev S.A., Puzyr A.P.
Заглавие : Degradation of P(3HB) and P(3HB-co-3HV) in biological media
Место публикации : Journal of Biomaterials Science, Polymer Edition. - 2005. - Vol. 16, Is. 5. - С. 643-657. - ISSN 09205063 (ISSN) , DOI 10.1163/1568562053783678
Ключевые слова (''Своб.индексиров.''): degradation rate--fiber properties--morphology--poly(hydroxybutyrate-co-hydroxyvalerate) (p(3hb-co-3hv))--polyhydroxyalkanoates(phas)--polyhydroxybutyrate (p(3hb))--copolymers--degradation--differential scanning calorimetry--enzymes--morphology--scanning electron microscopy--tensile strength--tissue--transmission electron microscopy--degradation rate--fiber properties--polyhydroxyalkanoates (phas)--polyhydroxybutyrate (p(3hb))--biopolymers--buffer--copolymer--poly(3 hydroxybutyric acid)--polyhydroxybutyrate hydroxyvalerate copolymer--unclassified drug--animal experiment--animal model--animal tissue--article--biodegradation--controlled study--crystal structure--fiber--giant cell--in vitro study--in vivo study--macrophage--morphology--nonhuman--ph--priority journal--rat--structure analysis--tensile strength--tissue water--weight reduction--animals--biodegradation, environmental--buffers--humans--hydrogen-ion concentration--hydroxybutyrates--macrophages--microscopy, electron, scanning--microscopy, electron, transmission--muscle, skeletal--polyesters--rats--rats, wistar
Аннотация: The biodegradability of oriented fibers made of polyhydroxybutyrate (P(3HB)) and its co-polymer with ?-hydroxyvalerate (P(3HB-co-3HV)) was investigated in buffer solutions and in biological media in vitro and in vivo. The fibers of both polymer types demonstrated resistance to hydrolytic degradation in buffer solutions at 38В°C and pH from 4.5 to 7.0 (for up to 180 days). It has been found that the biodegradation of the fibers in vitro in blood and serum and in vivo is accompanied by weight losses and minor changes in the microstructure with no significant losses in the tensile strength over a long time (up to 180 days). The biodegradation rate of the less crystalline co-polymer P(3HB-co-3HV) fibers was 1.4-2.0-times higher than that of the homopolymer P(3HB). It has also been shown that the degradation of the fibers in vivo is influenced both by tissue fluid enzymes and cells (macrophages and foreign-body giant cells). The fibers were eroded on the surface only with no gross defects and no dramatic effects on their mechanical performance. В© VSP 2005.
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16.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Volova T.G., Kalacheva G.S.
Заглавие : The synthesis of hydroxybutyrate and hydroxyvalerate copolymers by the bacterium Ralstonia eutropha
Место публикации : Mikrobiologiya. - 2005. - Vol. 74, Is. 1. - С. 63-69. - ISSN 00263656 (ISSN)
Ключевые слова (''Своб.индексиров.''): ?-ketothiolase--controlled synthesis--poly(hydroxybutyrate-co-hydroxyvalerate)--ralstonia eutropha--bacteria (microorganisms)--cupriavidus necator--acetoacetyl coenzyme a--acetyl coenzyme a acyltransferase--acyl coenzyme a--acyltransferase--butyric acid derivative--carbon dioxide--fructose--hydrogen--poly(3 hydroxybutyrate) co (3 hydroxyvalerate)--poly(3-hydroxyalkanoic acid) synthase--poly(3-hydroxybutyrate)-co-(3-hydroxyvalerate)--polyester--polyhydroxyalkanoate synthase--valeric acid derivative--article--chemistry--crystallization--culture medium--metabolism--wautersia eutropha--acetyl-coa c-acyltransferase--acyl coenzyme a--acyltransferases--butyrates--carbon dioxide--crystallization--culture media--cupriavidus necator--fructose--hydrogen--polyesters--valerates
Аннотация: The paper deals with the study of the synthesis of 3-hydroxybutyrate (3HB) and 3-hydroxyvalerate (3HV) copolymers by the bacterium Ralstonia eutropha B-5786 grown under different carbon nutrition conditions (growth on carbon dioxide, fructose, and CO2-valerate and fructose-valerate mixtures). The parameters to be analyzed included the yield of biomass, the yield, synthesis rate, and composition of copolymers, the activity of the key enzymes of polyhydroxyalkanoate (PHA) synthesis (?-ketothiolase, acetoacetyl-CoA reductase, and PHA synthase), the maximum tolerable concentration of valerate to the bacterium, and the conditions that govern the incorporation of hydroxyvalerate to copolymers. This allowed the relationship between cultivation conditions and the proportion of monomers in the copolymers to be deduced. We were able to synthesize a range of 3HB/3HV copolymers and found that the thermal characteristics and the degree of crystallinity of these copolymers depend on the molar fraction of 3HV.
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17.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Shishatskaya E.I.
Заглавие : Rubomycin microincapsulation with biodegradable polymer matrix
Место публикации : Antibiotiki i Khimioterapiya. - 2005. - Vol. 50, Is. 8-9. - С. 4-9. - ISSN 02352990 (ISSN)
Ключевые слова (''Своб.индексиров.''): daunorubicin (rubomycin)--microspheres--polyhydroxybutirate--antineoplastic antibiotic--daunorubicin--hydroxybutyric acid--microsphere--poly(3 hydroxybutyric acid)--poly-beta-hydroxybutyrate--polyester--polymer--article--chemistry--delayed release formulation--electronics--methodology--microcapsule--temperature--antibiotics, antineoplastic--capsules--daunorubicin--delayed-action preparations--hydroxybutyrates--microspheres--miniaturization--polyesters--polymers--temperature
Аннотация: A procedure for preparation of microspheres from biodegradable linear polyether of microbiological origin (polyhydroxybutirate, PHB) with using the technology of solvent evaporation was developed considering a specific example of two- and three-component emulsions. The procedure provided permanent preparation of the microspheres of high quality. The influence of the procedure (emulsion type, dispersion process and medium temperature) on the yield of the microspheres, their structure and size was shown. The temperature had a significant impact on incorporation of the antitumor anthracycline antibiotic daunorubicin (rubomycin) to the polymer matrix. The microspheres with various levels of the drug load (29 and 90% of the initial content in the emulsion) were prepared and the kinetics of the in vitro rubomycin release was studied. The dynamics of the highly toxic rubomycin release from the microspheres was on the whole even with the curve profile reaching the plateau in 20-22 hours of the observation period. The rate of the rubomycin release to the medium depended on the value of the antibiotic incorporation and was maximum within the first two hours (3.3 and 13.0 mcg/mlВ·h) that corresponded to the release of 0.97 and 3.89 of the incorporated antibiotic. The average rate of rubomycin release during 300 hours was 0.81В·10-4 and 2.3В·10-4 mcg/mlВ·h. The release constituted respectively 3.9 and 13.11% of the antibiotic incorporated to the microspheres.
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18.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Volova T.G., Trusova M.Y., Kalacheva G.S., Kozhevnicov I.V.
Заглавие : Physiological-biochemical properties and the ability to synthesize polyhydroxyalkanoates of the glucose-utilizing strain of the hydrogen bacterium Ralstonia eutropha B8562
Место публикации : Applied Microbiology and Biotechnology. - 2006. - Vol. 73, Is. 3. - С. 429-433. - ISSN 01757598 (ISSN) , DOI 10.1007/s00253-006-0460-0
Ключевые слова (''Своб.индексиров.''): biochemistry--carbon--genetic engineering--glucose--hydrogen--polyesters--cultural properties--glucose-utilizing mutant strain--nitrogen deficiency--polyhydroxyalkanoate (pha)--bacteria--3 hydroxybutyric acid--carbon dioxide--fructose--glucose--hydrogen--monomer--polyhydroxyalkanoic acid--sugar--bacterium--carbon--comparative study--energy--ester--experimental study--glucose--hydrogen--physicochemical property--article--bacterial strain--bacterium culture--bacterium mutant--biomass--chemical analysis--cupriavidus necator--energy consumption--genetic analysis--nonhuman--synthesis--bacteria (microorganisms)--cupriavidus necator
Аннотация: Physiological-biochemical, genetic, and cultural properties of the glucose-utilizing mutant strain Ralstonia eutropha B8562 have been compared with those of its parent strain R. eutropha B5786. It has been shown that growth characteristics of the strain cultured on glucose as the sole carbon and energy source are comparable with those of the parent strain. Strain B8562 is characterized by high polyhydroxyalkanoate (PHA) yields on different carbon sources (CO2, fructose, and glucose). PHA accumulation in the strain batch cultured on glucose under nitrogen deficiency reaches 90 %. The major monomer in the PHA is ?-hydroxybutyric acid (more than 99 mol %); the identified minor components are ?-hydroxyvaleric acid (0.25-0.72 mol %) and ?-hydroxyhexanoic acid (0.08-1.5 mol %). The strain is a promising PHA producer on available sugar-containing media with glucose. В© Springer-Verlag 2006.
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19.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Shishatskaya E.I.
Заглавие : Microencapculation of daunorubicin with biodegradable polymer matrix
Место публикации : Antibiotiki i Khimioterapiya. - 2007. - Vol. 52, Is. 9-10. - С. 3-8. - ISSN 02352990 (ISSN)
Ключевые слова (''Своб.индексиров.''): daunorubicin--microencapsulation--polymer matrix--antineoplastic antibiotic--daunorubicin--polyester--animal--article--bagg albino mouse--chemistry--kinetics--microcapsule--mouse--particle size--animals--antibiotics, antineoplastic--capsules--daunorubicin--kinetics--mice--mice, inbred balb c--particle size--polyesters--animalia
Аннотация: Procedure for microencapsulation providing stable formation of high quality microspheres was designed. Conditions for deposition of the anthracycline antibiotic daunorubicin to polymer matrix were developed and microsheres loaded with various quantities of the drug were prepared. The kinetics of the in vitro and in vivo release of daunorubicin from the microsheres was studied. The rate of the rubomycin release to the medium in vitro (balanced phosphate buffer at 37.8В°C) in a 300-hour experiment directly depended on the quantity of the incorporated drug and averaged 0.81 В· 10 -4 to 2.3 В· 10 -4 mcg/mlВ·h. The experiment on laboratory animals with intraperitoneal administration of the rubomycin microsperes showed that the drug remained in the blood and abdominal liquid for a long time (up to 10 days). Possible control of the quantity of the rubomycin encapsulation to the polymer matrix, no sharp efflux of the drug at the early stages of the observation and low rate of the drug release to the medium allowed to conclude that the use of the biodegradable polymer microsperes as carriers of the high toxic antibiotic providing its prolonged action was prospective.
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20.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Shishatskaya E.I., Voinova O.N., Goreva A.V., Mogilnaya O.A., Volova T.G.
Заглавие : Tissue reaction to intramuscular injection of resorbable polymer microparticles
Место публикации : Bulletin of Experimental Biology and Medicine. - 2007. - Vol. 144, Is. 6. - С. 786-790. - ISSN 00074888 (ISSN) , DOI 10.1007/s10517-007-0432-0
Ключевые слова (''Своб.индексиров.''): microencapsulation--polyhydroxybutyrate--resorbable polymers--tissue reaction--poly(3 hydroxybutyric acid)--polymer--animal experiment--animal tissue--article--cell infiltration--controlled study--drug delivery system--drug formulation--female--giant cell--inflammation--macrophage--microencapsulation--nonhuman--rat--tissue reaction--absorbable implants--animals--drug compounding--female--foreign-body reaction--injections, intramuscular--microspheres--polyesters--rats--rats, wistar
Аннотация: Tissue reaction to implantation of polymeric microparticles from resorbable polymer (polyhydroxybutyrate) is characterized by slight inflammatory reaction and pronounced progressive macrophage infiltration with the presence of mono-and multinuclear foreign body giant cells resorbing the polymeric matrix. No fibrous capsules were formed around the polymeric microparticles; neither necrosis nor other adverse morphological changes and tissue transformation in response to implantation of the PHB microparticles were recorded. The results indicate good prospects of using polyhydroxybutyrate for the construction of long-acting dosage forms as microparticles for intramuscular injection. В© Springer Science+Business Media, Inc. 2007.
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