Paul Kroll, P. Sagmeister, Wieland N Reichelt, L. Neutsch, Tobias Klein, C. Herwig
Monitoring of bioprocesses, especially biopharmaceutical production processes, is of utmost importance to ensure constant product quality and availability. Economical bioprocess development depends on time-efficient process development, aiming for in-depth understanding of the bioprocess and its critical parameters. Online monitoring of bioprocesses allows the assessment and processing of critical process data in real time. This is a prerequisite to permit real-time process management. Various devices for automated sampling and analysis, as well as data analysis and processing, have emerged over the last decade. In this review, we will cover the most important developments and novelties in the field of bioprocess monitoring from a methodological point of view. We focus on consolidation and processing of big amounts of data generated during a bioprocess and discuss how the proper interaction of hardware and software will improve bioprocess monitoring and control in the future.
{"title":"Ex situ online monitoring: application, challenges and opportunities for biopharmaceuticals processes","authors":"Paul Kroll, P. Sagmeister, Wieland N Reichelt, L. Neutsch, Tobias Klein, C. Herwig","doi":"10.4155/PBP.14.22","DOIUrl":"https://doi.org/10.4155/PBP.14.22","url":null,"abstract":"Monitoring of bioprocesses, especially biopharmaceutical production processes, is of utmost importance to ensure constant product quality and availability. Economical bioprocess development depends on time-efficient process development, aiming for in-depth understanding of the bioprocess and its critical parameters. Online monitoring of bioprocesses allows the assessment and processing of critical process data in real time. This is a prerequisite to permit real-time process management. Various devices for automated sampling and analysis, as well as data analysis and processing, have emerged over the last decade. In this review, we will cover the most important developments and novelties in the field of bioprocess monitoring from a methodological point of view. We focus on consolidation and processing of big amounts of data generated during a bioprocess and discuss how the proper interaction of hardware and software will improve bioprocess monitoring and control in the future.","PeriodicalId":90285,"journal":{"name":"Pharmaceutical bioprocessing","volume":"2 1","pages":"285-300"},"PeriodicalIF":0.0,"publicationDate":"2014-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.4155/PBP.14.22","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70347042","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}
The biopharmaceutical manufacturer of the future is nimble by design to rapidly adapt to new products and improved processes. The facility is primed with technical proficiency to anticipate consequences of process improvements, characterization of their current capabilities, flexibility to rapidly introduce new technology and expertise to mitigate risk. Recombinant protein manufacturing to date has primarily been orientated for timely delivery of exclusive large-volume products, ‘blockbusters’ to patients with access to the highest standard of care. Process development for the most part has focused on the regulatory requirements for quality, safety and efficacy. Thus, manufacturing science has evolved around issues such as elimination of animal-derived products, extractable leachables, and process qualification for viral and prion safety. Process development has achieved culture titers and recovery yields needed for a commercially viable process [1]. Thus, in the interest of speed to market, single-product facilities were built and more complex manufacturing efficiency issues were given secondary consideration. The future of recombinant protein products will include biosimilars, regional manufacturing and smaller volume, specialized products in multiproduct facilities, as biopharmaceutical manufactures strive to deliver drugs to a more diverse patient population at cheaper cost. As with most maturing industries, manufacturing efficiency will become more important. The biotechnology facility of the future will probably not be a ‘green field’ new installation. It could be an existing facility owned by a biopharmaceutical manufacturer, a facility acquired through merger or acquisition, or one rented from a contract manufacturing organization. It will probably be a hybrid with a layout suitable for single-use equipment, and piping and utilities for installed stainless steel equipment with reduced clean-inplace (CIP) and steam-in-place (SIP) systems [2]. Selection of the facility will depend on modifications required, portfolio of products manufactured and the new process fit. Facility modification will continue with adjacent areas such as warehouses and lobbies being added to the clean area of the facility and closed systems being installed in uncontrolled space. In addition, the demand for each product and facility staffing will often determine the best value along with the process flow diagram and regulatory requirements. Equipment selection to optimize return on investment will require analysis of each unit operation. For example, selecting a new bioreactor would need consideration of at least three options: single-use plastic, automated stainless steel or hybrid stainless steel surrounded by single-use auxiliary equipment to simplify CIP and SIP. For a multiproduct facility, each option will need analysis of the capital, component, raw material and utility costs for four operating modes: production, turnaround between batches, product changeovers
{"title":"Biopharmaceutical manufacturing and flexible design: what does the future hold?","authors":"Joseph Mclaughlin, A. Banerjee","doi":"10.4155/PBP.14.20","DOIUrl":"https://doi.org/10.4155/PBP.14.20","url":null,"abstract":"The biopharmaceutical manufacturer of the future is nimble by design to rapidly adapt to new products and improved processes. The facility is primed with technical proficiency to anticipate consequences of process improvements, characterization of their current capabilities, flexibility to rapidly introduce new technology and expertise to mitigate risk. Recombinant protein manufacturing to date has primarily been orientated for timely delivery of exclusive large-volume products, ‘blockbusters’ to patients with access to the highest standard of care. Process development for the most part has focused on the regulatory requirements for quality, safety and efficacy. Thus, manufacturing science has evolved around issues such as elimination of animal-derived products, extractable leachables, and process qualification for viral and prion safety. Process development has achieved culture titers and recovery yields needed for a commercially viable process [1]. Thus, in the interest of speed to market, single-product facilities were built and more complex manufacturing efficiency issues were given secondary consideration. The future of recombinant protein products will include biosimilars, regional manufacturing and smaller volume, specialized products in multiproduct facilities, as biopharmaceutical manufactures strive to deliver drugs to a more diverse patient population at cheaper cost. As with most maturing industries, manufacturing efficiency will become more important. The biotechnology facility of the future will probably not be a ‘green field’ new installation. It could be an existing facility owned by a biopharmaceutical manufacturer, a facility acquired through merger or acquisition, or one rented from a contract manufacturing organization. It will probably be a hybrid with a layout suitable for single-use equipment, and piping and utilities for installed stainless steel equipment with reduced clean-inplace (CIP) and steam-in-place (SIP) systems [2]. Selection of the facility will depend on modifications required, portfolio of products manufactured and the new process fit. Facility modification will continue with adjacent areas such as warehouses and lobbies being added to the clean area of the facility and closed systems being installed in uncontrolled space. In addition, the demand for each product and facility staffing will often determine the best value along with the process flow diagram and regulatory requirements. Equipment selection to optimize return on investment will require analysis of each unit operation. For example, selecting a new bioreactor would need consideration of at least three options: single-use plastic, automated stainless steel or hybrid stainless steel surrounded by single-use auxiliary equipment to simplify CIP and SIP. For a multiproduct facility, each option will need analysis of the capital, component, raw material and utility costs for four operating modes: production, turnaround between batches, product changeovers","PeriodicalId":90285,"journal":{"name":"Pharmaceutical bioprocessing","volume":"2 1","pages":"215-217"},"PeriodicalIF":0.0,"publicationDate":"2014-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.4155/PBP.14.20","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70347376","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}
Manufacturing of viral vectors comprises the generation of these vectors, which then have to be purified in order to meet the quality attributes required for further use as gene delivery systems. The first part of this article deals with the production of the most important viral vectors used in gene therapy protocols. In the second part, we briefly review the most current methods used for the purification of viral gene therapy products focusing on four viral vectors that have been the most extensively used in clinical trials: adenoviral, adeno-associated viral and lentiviral vectors. Traditionally, γ-retroviral vectors were not purified and clarified vectors containing culture supernatant was directly used for ex vivo gene therapy. The final section of this article reviews some of the basic biosafety considerations specific to the respective viral vectors.
{"title":"Manufacturing of viral vectors: part II. Downstream processing and safety aspects","authors":"O. Merten, M. Schweizer, P. Chahal, A. Kamen","doi":"10.4155/PBP.14.15","DOIUrl":"https://doi.org/10.4155/PBP.14.15","url":null,"abstract":"Manufacturing of viral vectors comprises the generation of these vectors, which then have to be purified in order to meet the quality attributes required for further use as gene delivery systems. The first part of this article deals with the production of the most important viral vectors used in gene therapy protocols. In the second part, we briefly review the most current methods used for the purification of viral gene therapy products focusing on four viral vectors that have been the most extensively used in clinical trials: adenoviral, adeno-associated viral and lentiviral vectors. Traditionally, γ-retroviral vectors were not purified and clarified vectors containing culture supernatant was directly used for ex vivo gene therapy. The final section of this article reviews some of the basic biosafety considerations specific to the respective viral vectors.","PeriodicalId":90285,"journal":{"name":"Pharmaceutical bioprocessing","volume":"2 1","pages":"237-251"},"PeriodicalIF":0.0,"publicationDate":"2014-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.4155/PBP.14.15","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70346693","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}
Introduction: Automated microbioreactor systems are designed for intensive bioprocess characterization. They facilitate reduction of development timelines without loss of valuable information. The RoboLector automated microbioreactor system was used for joint investigation of induction profiling and inoculation from seed cultures of different ages, which is only rarely recognized in literature for optimization. Results: The microbioreactor system allows reliable detection of growth phases and accurate inoculation procedures in combination with a true walk-away performance. Inocula taken from seed cultures resting in stationary growth phase for up to 10 h had no influence on induction profiling experiments, where late induction is preferred for maximum space-time-yield of recombinant enzyme production. Conclusion: The presented method allows for conduction of precise inoculation procedures and thus, for detailed studies on influential bioprocess parameters. The findings indicate that standardization in met...
{"title":"Automated microbioreactor systems for pharmaceutical bioprocessing: profiling of seeding and induction conditions in high-throughput fermentations","authors":"J. Hemmerich, F. Kensy","doi":"10.4155/PBP.14.18","DOIUrl":"https://doi.org/10.4155/PBP.14.18","url":null,"abstract":"Introduction: Automated microbioreactor systems are designed for intensive bioprocess characterization. They facilitate reduction of development timelines without loss of valuable information. The RoboLector automated microbioreactor system was used for joint investigation of induction profiling and inoculation from seed cultures of different ages, which is only rarely recognized in literature for optimization. Results: The microbioreactor system allows reliable detection of growth phases and accurate inoculation procedures in combination with a true walk-away performance. Inocula taken from seed cultures resting in stationary growth phase for up to 10 h had no influence on induction profiling experiments, where late induction is preferred for maximum space-time-yield of recombinant enzyme production. Conclusion: The presented method allows for conduction of precise inoculation procedures and thus, for detailed studies on influential bioprocess parameters. The findings indicate that standardization in met...","PeriodicalId":90285,"journal":{"name":"Pharmaceutical bioprocessing","volume":"2 1","pages":"227-235"},"PeriodicalIF":0.0,"publicationDate":"2014-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.4155/PBP.14.18","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70347196","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}
Nicholas R. Abu-Absi, R. Martel, A. M. Lanza, Stacey Clements, Michael C. Borys, Z. Li
The ability to monitor and control bioreactor processes is an integral component to the implementation of Process Analytical Technology and Quality by Design principles. Desirable attributes of monitoring methods include the ability to monitor multiple analytes in real time with little to no sample processing. Spectroscopic methods fit these criteria and significant advancements in their application have been made. However, implementation of these systems has been hampered by their complexity. Here, we present an overview of near IR, mid-IR, Raman and fluorescence spectroscopy technologies, and the steps taken to enable their implementation as effective bioprocess monitoring tools. Specific applications for monitoring of microbial and mammalian cell bioreactors, and screening and classification of raw materials are discussed.
{"title":"Application of spectroscopic methods for monitoring of bioprocesses and the implications for the manufacture of biologics","authors":"Nicholas R. Abu-Absi, R. Martel, A. M. Lanza, Stacey Clements, Michael C. Borys, Z. Li","doi":"10.4155/PBP.14.24","DOIUrl":"https://doi.org/10.4155/PBP.14.24","url":null,"abstract":"The ability to monitor and control bioreactor processes is an integral component to the implementation of Process Analytical Technology and Quality by Design principles. Desirable attributes of monitoring methods include the ability to monitor multiple analytes in real time with little to no sample processing. Spectroscopic methods fit these criteria and significant advancements in their application have been made. However, implementation of these systems has been hampered by their complexity. Here, we present an overview of near IR, mid-IR, Raman and fluorescence spectroscopy technologies, and the steps taken to enable their implementation as effective bioprocess monitoring tools. Specific applications for monitoring of microbial and mammalian cell bioreactors, and screening and classification of raw materials are discussed.","PeriodicalId":90285,"journal":{"name":"Pharmaceutical bioprocessing","volume":"2 1","pages":"267-284"},"PeriodicalIF":0.0,"publicationDate":"2014-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.4155/PBP.14.24","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70347623","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}
The impetus to accelerate process development in the biopharmaceutical industry is driven by reducing costs and time to market. Shortening development times is critical to the success of the industry [1]. The miniaturization of bioprocessing assists in the generation of quantitative data, fast and efficiently. This helps inform bioprocess design and speeds translation to the manufacturing scale. The meeting reviewed individual operations in the bioprocess workflow highlighting the state-of-the-art in technology and research and innovation. A brief overview of the themes covered is discussed below.
{"title":"EuroSciCon meeting on bioprocess miniaturization: development and optimization 26 November 2013, London, UK","authors":"Fiona Pereira","doi":"10.4155/PBP.14.9","DOIUrl":"https://doi.org/10.4155/PBP.14.9","url":null,"abstract":"The impetus to accelerate process development in the biopharmaceutical industry is driven by reducing costs and time to market. Shortening development times is critical to the success of the industry [1]. The miniaturization of bioprocessing assists in the generation of quantitative data, fast and efficiently. This helps inform bioprocess design and speeds translation to the manufacturing scale. The meeting reviewed individual operations in the bioprocess workflow highlighting the state-of-the-art in technology and research and innovation. A brief overview of the themes covered is discussed below.","PeriodicalId":90285,"journal":{"name":"Pharmaceutical bioprocessing","volume":"2 1","pages":"115-116"},"PeriodicalIF":0.0,"publicationDate":"2014-06-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.4155/PBP.14.9","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70350229","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}
{"title":"Report on 10th Annual bioProcess UK Conference 3–4 December 2013, London, UK","authors":"A. Velayudhan, Andrew Davidson","doi":"10.4155/PBP.14.10","DOIUrl":"https://doi.org/10.4155/PBP.14.10","url":null,"abstract":"","PeriodicalId":90285,"journal":{"name":"Pharmaceutical bioprocessing","volume":"2 1","pages":"117-119"},"PeriodicalIF":0.0,"publicationDate":"2014-06-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.4155/PBP.14.10","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70346667","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}
X. Mou, Xiaoyu Yang, Hong Li, A. Ambrogelly, D. Pollard
Background: Size exclusion chromatography (SEC) has been employed as an essential assay for aggregate characterization of in-process intermediates, release testing and stability studies of biologics (Q6B-ICH). Ultra-performance SEC (UP-SEC) that enables improved separation of different size species within a shorter running time than HP-SEC is highly desired. Results: We developed a 5-min UP-SEC assay based on BEH200 column for analysis of monoclonal antibodies on UPLC systems following screening of 13 different SEC columns. This UP-SEC assay has been evaluated with multiple antibody stability and in-process samples. The performance parameters including the resolution have been studied. Conclusion: This new UP-SEC method with 80% shorter running time has demonstrated better or equivalent separation efficiency than the HP-SEC method. This UP-SEC has been successfully implemented in bioprocess development and analytical testing.
{"title":"A high throughput ultra performance size exclusion chromatography assay for the analysis of aggregates and fragments of monoclonal antibodies","authors":"X. Mou, Xiaoyu Yang, Hong Li, A. Ambrogelly, D. Pollard","doi":"10.4155/PBP.14.7","DOIUrl":"https://doi.org/10.4155/PBP.14.7","url":null,"abstract":"Background: Size exclusion chromatography (SEC) has been employed as an essential assay for aggregate characterization of in-process intermediates, release testing and stability studies of biologics (Q6B-ICH). Ultra-performance SEC (UP-SEC) that enables improved separation of different size species within a shorter running time than HP-SEC is highly desired. Results: We developed a 5-min UP-SEC assay based on BEH200 column for analysis of monoclonal antibodies on UPLC systems following screening of 13 different SEC columns. This UP-SEC assay has been evaluated with multiple antibody stability and in-process samples. The performance parameters including the resolution have been studied. Conclusion: This new UP-SEC method with 80% shorter running time has demonstrated better or equivalent separation efficiency than the HP-SEC method. This UP-SEC has been successfully implemented in bioprocess development and analytical testing.","PeriodicalId":90285,"journal":{"name":"Pharmaceutical bioprocessing","volume":"2 1","pages":"141-156"},"PeriodicalIF":0.0,"publicationDate":"2014-06-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.4155/PBP.14.7","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70349903","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}
J. Heo, X. Mou, Fengqiang Wang, J. Troisi, Christopher W Sandifer, S. Kirby, D. Driscoll, Suzanne Mercorelli, D. Pollard
Background: Analysis of process-related impurities is critical for the control of biopharmaceutical processes and the quality of final biological products. Residual impurities in monoclonal antibody products such as host cell proteins (HCPs) increase the risk of immunogenicity and may directly affect drug potency. Commonly used HCP ELISA often involves complicated sample preparation, lengthy operation, and large volumes of reagent. To overcome these challenges, a fully automated CHO HCP assay was developed using a microfluidic platform (MFP) system and compared with existing plate-based ELISA for quantification of HCP in monoclonal antibody purification intermediates. Results: The automated MFP based assay approach enabled an improved throughput (5–10-times faster), broader dynamic range (100-times) and decreased sample consumption, hands on time and duration for assay development compared with Tecan plate-based ELISA. Conclusion: The newly developed microfluidic assay demonstrated its advantages over pla...
{"title":"A microfluidic approach to high throughput quantification of host cell protein impurities for bioprocess development","authors":"J. Heo, X. Mou, Fengqiang Wang, J. Troisi, Christopher W Sandifer, S. Kirby, D. Driscoll, Suzanne Mercorelli, D. Pollard","doi":"10.4155/PBP.14.12","DOIUrl":"https://doi.org/10.4155/PBP.14.12","url":null,"abstract":"Background: Analysis of process-related impurities is critical for the control of biopharmaceutical processes and the quality of final biological products. Residual impurities in monoclonal antibody products such as host cell proteins (HCPs) increase the risk of immunogenicity and may directly affect drug potency. Commonly used HCP ELISA often involves complicated sample preparation, lengthy operation, and large volumes of reagent. To overcome these challenges, a fully automated CHO HCP assay was developed using a microfluidic platform (MFP) system and compared with existing plate-based ELISA for quantification of HCP in monoclonal antibody purification intermediates. Results: The automated MFP based assay approach enabled an improved throughput (5–10-times faster), broader dynamic range (100-times) and decreased sample consumption, hands on time and duration for assay development compared with Tecan plate-based ELISA. Conclusion: The newly developed microfluidic assay demonstrated its advantages over pla...","PeriodicalId":90285,"journal":{"name":"Pharmaceutical bioprocessing","volume":"2 1","pages":"129-139"},"PeriodicalIF":0.0,"publicationDate":"2014-06-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.4155/PBP.14.12","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70346866","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}
{"title":"The future for biosensors in biopharmaceutical production","authors":"D. Bracewell, K. Polizzi","doi":"10.4155/PBP.14.4","DOIUrl":"https://doi.org/10.4155/PBP.14.4","url":null,"abstract":"","PeriodicalId":90285,"journal":{"name":"Pharmaceutical bioprocessing","volume":"2 1","pages":"121-124"},"PeriodicalIF":0.0,"publicationDate":"2014-06-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.4155/PBP.14.4","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70347976","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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