The aim of this research was to develop a bioadhesive film based on benzydamine hydrochloride incorporated into natural bioadhesive polymers with different quantities of chitosan and guar gum but utilising a plasticiser. The obtained gels were deaerated by sonification, formed and evaporated by hot air drying; then, the properties were evaluated. Guar gum had a great influence on mechanical properties of the films – dynamic viscosity, texture, elasticity, stretching robustness, swelling and blur time. The formulations were used to obtain mucoadhesive films containing 0.3% benzydamine hydrochloride; they were tested for the release of the model drug. The amount of chitosan added to the formulation reduced the quantity of released substance and slowed down the release. Fouriertransform infrared spectroscopy did not reveal the creation of new chemical structures. In conclusion, the ratio of chitosan to guar gum in the medium impacts the mechanical properties and release parameters of the drug. These findings should enable researchers to match the parameter values to receive the most beneficial therapeutic outcome.
{"title":"FORMULATION AND CHARACTERISATION OF MUCOADHESIVE DENTAL APPLICATIONS CONTAINING BENZYDAMINE HYDROCHLORIDE","authors":"B. Grimling","doi":"10.15259/pcacd.26.006","DOIUrl":"https://doi.org/10.15259/pcacd.26.006","url":null,"abstract":"The aim of this research was to develop a bioadhesive film based on benzydamine hydrochloride incorporated into natural bioadhesive polymers with different quantities of chitosan and guar gum but utilising a plasticiser. The obtained gels were deaerated by sonification, formed and evaporated by hot air drying; then, the properties were evaluated. Guar gum had a great influence on mechanical properties of the films – dynamic viscosity, texture, elasticity, stretching robustness, swelling and blur time. The formulations were used to obtain mucoadhesive films containing 0.3% benzydamine hydrochloride; they were tested for the release of the model drug. The amount of chitosan added to the formulation reduced the quantity of released substance and slowed down the release. Fouriertransform infrared spectroscopy did not reveal the creation of new chemical structures. In conclusion, the ratio of chitosan to guar gum in the medium impacts the mechanical properties and release parameters of the drug. These findings should enable researchers to match the parameter values to receive the most beneficial therapeutic outcome.","PeriodicalId":44461,"journal":{"name":"Progress on Chemistry and Application of Chitin and its Derivatives","volume":" ","pages":""},"PeriodicalIF":0.6,"publicationDate":"2021-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43606492","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Effective antibacterial coatings are in demand in medicine, especially for urological medical devices such as catheters and stents. We propose the production method of an antibacterial hydrogel coating on polydimethylsiloxane (PDMS, silicone), a popular surface for medical materials. The coating process consists of the following steps: PDMS surface activation (introduction of hydroxyl groups), silanisation (introduction of amine groups) and application of chitosan/alginate hydrogel with the addition of lysozyme as an antibacterial agent using the layer-by-layer method. We investigated the effect of polyion concentration on the coating mass, swelling ratio and stability. We analysed the adsorption of Micrococcus luteus, Escherichia coli and Proteus rettgeri on a PDMS surface using confocal laser scanning microscopy. The chitosan/alginate hydrogel coating with immobilised lysozyme protected the PDMS surface against adhesion for all three tested bacterial strains.
{"title":"HYDROGEL ANTIBACTERIAL COATING FOR SILICONE MEDICAL DEVICES","authors":"Kamil Kopeć, Michał Żuk, T. Ciach","doi":"10.15259/pcacd.26.012","DOIUrl":"https://doi.org/10.15259/pcacd.26.012","url":null,"abstract":"Effective antibacterial coatings are in demand in medicine, especially for urological medical devices such as catheters and stents. We propose the production method of an antibacterial hydrogel coating on polydimethylsiloxane (PDMS, silicone), a popular surface for medical materials. The coating process consists of the following steps: PDMS surface activation (introduction of hydroxyl groups), silanisation (introduction of amine groups) and application of chitosan/alginate hydrogel with the addition of lysozyme as an antibacterial agent using the layer-by-layer method. We investigated the effect of polyion concentration on the coating mass, swelling ratio and stability. We analysed the adsorption of Micrococcus luteus, Escherichia coli and Proteus rettgeri on a PDMS surface using confocal laser scanning microscopy. The chitosan/alginate hydrogel coating with immobilised lysozyme protected the PDMS surface against adhesion for all three tested bacterial strains.","PeriodicalId":44461,"journal":{"name":"Progress on Chemistry and Application of Chitin and its Derivatives","volume":" ","pages":""},"PeriodicalIF":0.6,"publicationDate":"2021-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42734915","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Treatment of chitosan with ionising radiation is one of the methods by which it is modified for various applications. However, in the case of chitosan irradiated in the solid state, the radicals formed during irradiation can be stabilised in its crystalline phase and subsequently cause post-irradiation changes. It has been observed that further degradation of the polymer occurs during storage of the irradiated polymer, resulting in an increase in oxidation products and a decrease in deacetylation degree. This effect results from the transformation of radicals leading to the formation of stable nitroxyl radicals, a process observed years after irradiation.
{"title":"LONG-TERM RADIATION-INDUCED EFFECTS ON SOLID STATE CHITOSAN","authors":"U. Gryczka","doi":"10.15259/pcacd.26.007","DOIUrl":"https://doi.org/10.15259/pcacd.26.007","url":null,"abstract":"Treatment of chitosan with ionising radiation is one of the methods by which it is modified for various applications. However, in the case of chitosan irradiated in the solid state, the radicals formed during irradiation can be stabilised in its crystalline phase and subsequently cause post-irradiation changes. It has been observed that further degradation of the polymer occurs during storage of the irradiated polymer, resulting in an increase in oxidation products and a decrease in deacetylation degree. This effect results from the transformation of radicals leading to the formation of stable nitroxyl radicals, a process observed years after irradiation.","PeriodicalId":44461,"journal":{"name":"Progress on Chemistry and Application of Chitin and its Derivatives","volume":" ","pages":""},"PeriodicalIF":0.6,"publicationDate":"2021-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49537630","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Epidemics of infectious diseases have always been a threat to humanity and have contributed to increased mortality in the affected areas. This also applies to a new species of coronavirus identified in 2019, SARS-CoV-2, which is responsible for the COVID-19 pandemic. Despite preventive measures implemented all over the world to minimise the spread of the pathogen as well as the development of vaccines, which have been approved for emergency use, the situation is still worrying. Moreover, the problem is exacerbated by the lack of targeted treatments for COVID-19 patients. One possible solution is the using preparations based on natural raw materials, including chitosan. This biopolymer is of great interest due to a number of unique biological properties, among which its antiviral effect is a key feature. Hence, this paper presents the application possibilities of chitosan-based solutions in the prevention and treatment of viral diseases, with particular emphasis on COVID-19.
{"title":"SARS-COV-2 – THE LATEST GLOBAL THREAT AND THE PROSPECT OF COVID-19 THERAPY WITH THE USE OF CHITOSAN","authors":"K. Pieklarz, Z. Modrzejewska","doi":"10.15259/pcacd.26.004","DOIUrl":"https://doi.org/10.15259/pcacd.26.004","url":null,"abstract":"Epidemics of infectious diseases have always been a threat to humanity and have contributed to increased mortality in the affected areas. This also applies to a new species of coronavirus identified in 2019, SARS-CoV-2, which is responsible for the COVID-19 pandemic. Despite preventive measures implemented all over the world to minimise the spread of the pathogen as well as the development of vaccines, which have been approved for emergency use, the situation is still worrying. Moreover, the problem is exacerbated by the lack of targeted treatments for COVID-19 patients. One possible solution is the using preparations based on natural raw materials, including chitosan. This biopolymer is of great interest due to a number of unique biological properties, among which its antiviral effect is a key feature. Hence, this paper presents the application possibilities of chitosan-based solutions in the prevention and treatment of viral diseases, with particular emphasis on COVID-19.","PeriodicalId":44461,"journal":{"name":"Progress on Chemistry and Application of Chitin and its Derivatives","volume":" ","pages":""},"PeriodicalIF":0.6,"publicationDate":"2021-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47752244","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
O. Kalinkevich, A. Sklyar, A. Kalinkevich, V. Chivanov, Yevgen Zinchenko, Yana V. Trofimenko, V. Starikov, D. Sofronov, V. Holubnycha
New composite materials were obtained based on chitosan iodide and organic dyes – methylene blue and fuchsine in fucorcin (Castellani liquid) – by using a simple synthetic procedure. The materials were characterised by scanning electron microscopy, X-ray diffraction, temperature-programmed desorption mass spectrometry, infrared spectroscopy and visible and ultraviolet light spectroscopy. The dyes in the composites were distributed uniformly and did not form separate phases. These composites could form structured porous sponges and films and therefore be used in various fields of application. The materials displayed antibacterial activity against antibiotic resistant gram-positive and gram-negative bacteria.
{"title":"PREPARATION AND CHARACTERISATION OF NEW BIOMATERIALS BASED ON CHITOSAN IODIDE WITH BIOLOGICALLY ACTIVE DYES","authors":"O. Kalinkevich, A. Sklyar, A. Kalinkevich, V. Chivanov, Yevgen Zinchenko, Yana V. Trofimenko, V. Starikov, D. Sofronov, V. Holubnycha","doi":"10.15259/pcacd.26.011","DOIUrl":"https://doi.org/10.15259/pcacd.26.011","url":null,"abstract":"New composite materials were obtained based on chitosan iodide and organic dyes – methylene blue and fuchsine in fucorcin (Castellani liquid) – by using a simple synthetic procedure. The materials were characterised by scanning electron microscopy, X-ray diffraction, temperature-programmed desorption mass spectrometry, infrared spectroscopy and visible and ultraviolet light spectroscopy. The dyes in the composites were distributed uniformly and did not form separate phases. These composites could form structured porous sponges and films and therefore be used in various fields of application. The materials displayed antibacterial activity against antibiotic resistant gram-positive and gram-negative bacteria.","PeriodicalId":44461,"journal":{"name":"Progress on Chemistry and Application of Chitin and its Derivatives","volume":" ","pages":""},"PeriodicalIF":0.6,"publicationDate":"2021-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45268577","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Among the diseases of the digestive tract, gastro-oesophageal reflux is one of the most troublesome ailments. It is estimated that in highly developed countries, reflux symptoms occur in about 5%-10% of people every day. It has also been found that about 20% of people experience such symptoms once a week. The incidence of this disease increases with age, regardless of gender. The aim of the study was to investigate the physicochemical properties of gels intended for the protection of the oesophageal mucosa. Preparations containing 3.0% pectin showed the lowest pH. These gels can be used in the treatment of advanced alkaline reflux. The addition of chitosan to all tested gels increased their pH and dynamic viscosity. The texture tests showed the effect of pectin concentration on the adhesion work of the tested gels.
{"title":"INFLUENCE OF PECTIN AND CHITOSAN ON THE PROPERTIES OF GELS PROTECTING THE OESOPHAGEAL MUCOSA","authors":"K. Małolepsza-Jarmołowska","doi":"10.15259/pcacd.26.014","DOIUrl":"https://doi.org/10.15259/pcacd.26.014","url":null,"abstract":"Among the diseases of the digestive tract, gastro-oesophageal reflux is one of the most troublesome ailments. It is estimated that in highly developed countries, reflux symptoms occur in about 5%-10% of people every day. It has also been found that about 20% of people experience such symptoms once a week. The incidence of this disease increases with age, regardless of gender. The aim of the study was to investigate the physicochemical properties of gels intended for the protection of the oesophageal mucosa. Preparations containing 3.0% pectin showed the lowest pH. These gels can be used in the treatment of advanced alkaline reflux. The addition of chitosan to all tested gels increased their pH and dynamic viscosity. The texture tests showed the effect of pectin concentration on the adhesion work of the tested gels.","PeriodicalId":44461,"journal":{"name":"Progress on Chemistry and Application of Chitin and its Derivatives","volume":" ","pages":""},"PeriodicalIF":0.6,"publicationDate":"2021-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46029705","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A series of N,O-acylated chitosan derivatives were emulsified with different fatty acids. Hydrophobically modified chitosan derivatives were expected to exhibit self-assembly behaviour resulting in micelle formation. Several parameters of the oil-in-water emulsification process were investigated: mixing method, speed and duration, volume oil phase and addition of modifiers. Their influence on micellar Z-average diameter, size distribution and Zeta potential was analysed based on dynamic light scattering measurements. There were various relations between the hydrodynamic behaviour of chitosan derivatives, their chemical structure and the process parameters. Additionally, the obtained micelles could serve as active compound carriers because they encapsulated two model substances, namely ibuprofen and α-tocopherol.
{"title":"EMULSIFICATION PARAMETERS STUDY ON MICELLES FORMATION FROM HYDROPHOBICALLY MODIFIED CHITOSAN","authors":"A. Piegat, A. Niemczyk, Agata Goszczyńska","doi":"10.15259/pcacd.26.016","DOIUrl":"https://doi.org/10.15259/pcacd.26.016","url":null,"abstract":"A series of N,O-acylated chitosan derivatives were emulsified with different fatty acids. Hydrophobically modified chitosan derivatives were expected to exhibit self-assembly behaviour resulting in micelle formation. Several parameters of the oil-in-water emulsification process were investigated: mixing method, speed and duration, volume oil phase and addition of modifiers. Their influence on micellar Z-average diameter, size distribution and Zeta potential was analysed based on dynamic light scattering measurements. There were various relations between the hydrodynamic behaviour of chitosan derivatives, their chemical structure and the process parameters. Additionally, the obtained micelles could serve as active compound carriers because they encapsulated two model substances, namely ibuprofen and α-tocopherol.","PeriodicalId":44461,"journal":{"name":"Progress on Chemistry and Application of Chitin and its Derivatives","volume":" ","pages":""},"PeriodicalIF":0.6,"publicationDate":"2021-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43395589","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
U. Jankiewicz, Arletta Kochańska-Jeziorska, Agnieszka Gałązka
This review focuses on the enzymatic breakdown of chitin, taking into account the latest scientific reports on the activity of lytic polysaccharide monooxygenase (LPMO). Chitin is a natural, abundant polysaccharide of great practical importance in the environment. However, the insolubility in water and the tightly packed crystalline structure of chitin pose a serious obstacle to enzymatic degradation. This substrate can be converted into soluble sugars by the action of glycosidic hydrolases (GH), also known as chitinases. LPMO could prove to be helpful in enzymatic processes that increase the rate of chitin depolymerisation by improving the availability of substrates for chitinases. The unique action of LPMO is based on the ability to catalyse the oxidative cleavage of glycosidic chains present in complex, resistant crystal networks of chitin, and this cleavage facilitates the subsequent action of glycolytic hydrolases.
{"title":"NEW ASPECTS OF THE ENZYMATIC BREAKDOWN OF CHITIN: A REVIEW","authors":"U. Jankiewicz, Arletta Kochańska-Jeziorska, Agnieszka Gałązka","doi":"10.15259/pcacd.26.001","DOIUrl":"https://doi.org/10.15259/pcacd.26.001","url":null,"abstract":"This review focuses on the enzymatic breakdown of chitin, taking into account the latest scientific reports on the activity of lytic polysaccharide monooxygenase (LPMO). Chitin is a natural, abundant polysaccharide of great practical importance in the environment. However, the insolubility in water and the tightly packed crystalline structure of chitin pose a serious obstacle to enzymatic degradation. This substrate can be converted into soluble sugars by the action of glycosidic hydrolases (GH), also known as chitinases. LPMO could prove to be helpful in enzymatic processes that increase the rate of chitin depolymerisation by improving the availability of substrates for chitinases. The unique action of LPMO is based on the ability to catalyse the oxidative cleavage of glycosidic chains present in complex, resistant crystal networks of chitin, and this cleavage facilitates the subsequent action of glycolytic hydrolases.","PeriodicalId":44461,"journal":{"name":"Progress on Chemistry and Application of Chitin and its Derivatives","volume":" ","pages":""},"PeriodicalIF":0.6,"publicationDate":"2021-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48805868","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. Konovalova, D. Tsaregorodtseva, E. Svirshchevskaya
An increase in the number and volume of surgical interventions leads to an increase in the frequency of postoperative adhesions. The development of the adhesion process in the abdominal cavity causes pain, a decrease in the quality of life of patients, a violation of the reproductive function of women as well as acute adhesion intestinal obstruction. Recently, polymer biomaterials, including those based on chitosan, have been widely used for the prevention of adhesions. Due to their biocompatibility and biodegradation ability, they do not require repeated operations to extract the material. It is believed that these materials act as barriers, physically separating the damaged surfaces. The molecular mechanism of their action is still poorly understood. In this review, the main mechanisms of adhesion formation, as well as ways to prevent them with the help of materials based on chitosan and its derivatives, are discussed.
{"title":"BIOMATERIALS BASED ON CHITOSAN AND ITS DERIVATIVES TO PREVENT ADHESION FORMATION","authors":"M. Konovalova, D. Tsaregorodtseva, E. Svirshchevskaya","doi":"10.15259/pcacd.26.002","DOIUrl":"https://doi.org/10.15259/pcacd.26.002","url":null,"abstract":"An increase in the number and volume of surgical interventions leads to an increase in the frequency of postoperative adhesions. The development of the adhesion process in the abdominal cavity causes pain, a decrease in the quality of life of patients, a violation of the reproductive function of women as well as acute adhesion intestinal obstruction. Recently, polymer biomaterials, including those based on chitosan, have been widely used for the prevention of adhesions. Due to their biocompatibility and biodegradation ability, they do not require repeated operations to extract the material. It is believed that these materials act as barriers, physically separating the damaged surfaces. The molecular mechanism of their action is still poorly understood. In this review, the main mechanisms of adhesion formation, as well as ways to prevent them with the help of materials based on chitosan and its derivatives, are discussed.","PeriodicalId":44461,"journal":{"name":"Progress on Chemistry and Application of Chitin and its Derivatives","volume":" ","pages":""},"PeriodicalIF":0.6,"publicationDate":"2021-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43261193","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
O. Kadyseva, V. N. Bykov, O. Strelova, A. Grebenyuk
Chitosan are biopolymers that are actively used for the production of local haemostatic agents. The physicochemical characteristics that determine its biological properties include the molecular weight and the deacetylation degree. However, there is no linear relationship between these parameters and haemostatic activity. The most reliable method of confirming the effectiveness is still in vivo experiments. The ability to initiate haemostasis depends on the conformational transition of chitosan macromolecules. The highest efficiency in vitro was for samples in which the transition of a significant part of the molecules from the ‘rigid rod’ state to the ‘globule’ occurred at physiological pH. It is proposed to expand the list of indicators of chitosan that can be controlled to evaluate the quality of raw materials, related to haemostatic activity, to include the definition of the conformational transition at physiological pH.
{"title":"STUDY OF THE EFFECT OF THE PHYSICOCHEMICAL PROPERTIES OF CHITOSAN ON ITS HAEMOSTATIC ACTIVITY","authors":"O. Kadyseva, V. N. Bykov, O. Strelova, A. Grebenyuk","doi":"10.15259/pcacd.26.010","DOIUrl":"https://doi.org/10.15259/pcacd.26.010","url":null,"abstract":"Chitosan are biopolymers that are actively used for the production of local haemostatic agents. The physicochemical characteristics that determine its biological properties include the molecular weight and the deacetylation degree. However, there is no linear relationship between these parameters and haemostatic activity. The most reliable method of confirming the effectiveness is still in vivo experiments. The ability to initiate haemostasis depends on the conformational transition of chitosan macromolecules. The highest efficiency in vitro was for samples in which the transition of a significant part of the molecules from the ‘rigid rod’ state to the ‘globule’ occurred at physiological pH. It is proposed to expand the list of indicators of chitosan that can be controlled to evaluate the quality of raw materials, related to haemostatic activity, to include the definition of the conformational transition at physiological pH.","PeriodicalId":44461,"journal":{"name":"Progress on Chemistry and Application of Chitin and its Derivatives","volume":" ","pages":""},"PeriodicalIF":0.6,"publicationDate":"2021-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45556330","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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