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The Invention: In vitro cell culture methodologies provide a conducive environment for the cells taken out of their native environment to grow and proliferate in a non-physiological environment, the culture dish. Research experiments have been focusing on various criteria for assessing how far it is possible to recapitulate the native extra-cellular environment in vitro. Scaffolds, culture media, growth factors and cell surface modified culture dishes are some of the components that provide a conducive environment for in vitro cell culture. Cells that are grown in culture dishes using conventional methodologies are usually detached using enzymatic treatment with Trypsin, Collagenase etc [1], to be transplanted when it comes to a clinical or experimental application. Such enzymes used in separating the cells may have some damaging effects to the cell membranes which might impair the cell function [1]. However, cells if can be grown as a monolayer and be harvested as a contiguous cell sheet, it is considered suitable for transplantation in certain specific applications. In addition to that, if enzymatic digestion which has some detrimental effects on the detached cells could be avoided, that is an added advantage. The work by Prof. Okano and team from the Tokyo Women's Medical University, Japan, on thermo-responsive polymer surfaces has yielded a solution which has both the advantages viz., detachability of cells grown as a monolayer in the form of a cell sheet, that too without the use of enzymes. Their research into biomaterials for more than two decades has yielded a thermo-responsive polymer, the poly(N-isopropylacrylamide) (PIPAAm) [1] coated culture dish for cell sheet engineering. In their technology, PIPAAm is polymerized and grafted to tissue culture polystyrene (TCPS) dishes. Cells have been found to grow confluent on PIPAAm-TCPS at 37 °C. Once confluent as a monolayer, by merely reducing the temperature of the PIPAAm-TCPS to 20 °C, it can be easily detached as a single contiguous cell sheet. The alteration of the surface from a hydrophobic to a hydrophilic state with the lowering of the temperature from 37 °C to 20 °C enables this easy separation which is the unique feature of this technology [2]. Different kinds of cells have been shown to adhere to, spread over the PIPAAm gel modified TCPS (PIPAAm-TCPS) and grow as cell sheets without any change in their respective phenotypes [2]. Inter-Disciplinary-Interaction: I, based on the Invention: Cardiovascular diseases remain the leading cause of death in the world. In 2010, 29.6% of all deaths worldwide were caused by cardiovascular diseases [3]. Conventional medical strategies for the treatment of heart failure resulting from myocardial infarction do not attempt to correct the underlying cause (i.e. loss of viable myocardial tissue), thereby raising the need for strategies aimed at myocardial regeneration and repair. At the other end of the spectrum, cardiac transplantation provides radical therapy, however, the donor organ shortage and strict eligibility criteria, mandate alternative treatments when a substantial portion of the myocardium has been destroyed. In this context, cellular cardiomyoplasty using cells and stem cells have been emerging as a possible means of regenerating damaged myocardium by preventing myocardial necrosis and promoting angiogenesis and myogenesis. Different kinds of cells and stem cells have been employed for treating heart failure. For instance, a team led by Prof. Cherian has employed granulocyte colony stimulating factor (GCSF) induced peripheral blood derived CD34+ endothelial progenitor cells (EPCs) or iliac crest bone marrow-derived mononuclear cells (MNCs) in treating 104 patients suffering from ischemic/dilated cardiomyopathy (autologus EPCs: 19 patients including allogenic paternal EPCs for one patient, autologus MNCs: 90 patients) at Frontier Lifeline Hospital in Chennai, India. A clinical trial was registered (CTRI/2009/091/000590) after standardizing the procedures for collection of autologous bone marrow cells in January 2010. Out of the 104 patients, 68 patients met the inclusion criteria for the trial follow up. Of the total, 45 patients could not be followed up in spite of the team’s best efforts to trace them. Only 23 patients (34%) were available for follow up. Amongst those, 19 patients (82.6%) were alive at the end of the first year and 10 out of the 19 patients (52.6%) had at least a 5% increase in the Ejection Fraction post therapy and had significant improvement in the functional status. The procedure was safe in all the other patients which were similar to the results of other studies reported so far. Though the results of this clinical trial infer that stem cells are not an alternative to heart transplantation they offer a 'dynamic cellular support' for regenerating functional and viable myocardium. As a step further in identifying definitive cell based therapy approaches to treat heart failure, cell sheet therapy was advocated by Prof. Sawa’s team. In Prof. Sawa’s Institute, longitudinal research team was launched in the late 1990s to develop new treatments for advanced cardiac disease by an array of basic experimental studies of surgical and regenerative approaches. As a result, placement of autologous or allogeneic stem/progenitor cell-sheets over the cardiac surface via surgical approach was proven to be the most safe and efficacious treatment for advanced cardiac failure. To grow the skeletal myoblasts as a sheet for clinical transplantation, Prof. Sawa’s team employed the thermo-responsive polymer dish developed by Prof. Okano’s team which enabled the in vitro growth of the skeletal myoblasts as patches and their easy separation for application over the ischemic/infarcted area of the heart after thorough validation in animal experiments [4]. A clinical study was, therefore, launched in 2006, wherein autologous skeletal myoblast cell-sheets were directly placed on the cardiac surface under general anaesthesia [5] for more than 30 patients with an ejection fraction below 35%. In this study, the cell-sheets were successfully placed without any procedure-related mortalities or morbidities, demonstrating the feasibility and safety of this treatment and importantly, majority of the patients have shown recovery of cardiac function and physical symptoms to date, indicating that this single treatment yields sustained functional recovery in patients having advanced cardiac failure [5]. This autologous skeletal myoblast sheet therapy to treat heart failure was conditionally approved as a cellular product in Japan on 2nd September 2015 [6]. Inter-Disciplinary-Interaction: II, based on the Invention: While cardiac diseases are the leading cause of death throughout the world, it is disheartening to note that there are 180 million people in the world with severe visual disability [7]. Corneal diseases follow cataract in being the second leading cause of blindness in these people [7]. The cornea is a five layered structure consisting of the Epithelial layer, Bowman’s membrane, Stroma, Descemet’s membrane and the Endothelium. Standalone corneal epithelial damage along with total damage of all the five layers of the cornea are considered to be contributing to 50% of the corneal blindness, as one half of the corneal transplantation indications to treat corneal blindness has been attributed to standalone corneal endothelial diseases [8]. In the case of corneal epithelium, limbus is the portion that harbours stem cells which repair the corneal epithelium. Cultivated limbal epithelial transplantation (CLET) is used for the management of limbal stem cell deficiency (LSCD) [9]. While biological scaffolds like human amniotic membrane have been used to culture and transplant the limbal stem cells, synthetic scaffolds like the thermo-reversible gelation polymer (TGP) offers potential advantages over biological scaffolds [10]. The TGP based limbal stem cell transplantation has been demonstrated successfully in animal model of limbal stem cell deficiency [10]. While the above is suitable for unilateral LSCD, in the case of bilateral total LSCD, corneal stem cell allograft transplantation [9] or cultivated oral mucosal epithelial transplantation (COMET) are the treatments of choice available at the moment. In the COMET procedure, autologous oral mucosa is cultured and transplanted to the affected corneas. There are no risks of immune-mediated rejection and in the absence of autoimmune disease, immunosuppression is not required. While the epithelial sheets from the autologous mucosa are cultured, use of thermo-responsive culture dishes have enabled a carrier-free epithelial cell sheet transplantation as the cell sheets after in vitro culture can be detached by merely lowering the temperature of the thermo-responsive culture dishes [11]. These oral mucosal epithelial sheets have been transplanted in patients with corneal epithelial diseases with positive outcome [11]. Perspectives: The thermo-responsive polymer dish based technological capability of being able to grow cells as a sheet which can be transplanted without any carrier onto the surface of an organ or a tissue that requires a support for regeneration has enabled two novel clinical applications: Myocardial regeneration using skeletal myoblast patches which has become an approved cellular therapy [6]. A solution to bilateral corneal limbal stem cell deficiency by transplantation of autologous oral mucosal epithelial sheet [11]. In both the applications, transplantation of cells as a monolayer-sheet instead of dispersed cells has been proven to be advantageous. In cornea the entire surface can be uniformly covered if a cell sheet is used rather than transplantation of clumps of cells logically and the mechanism of the regeneration has been shown to be the replacement of the damaged corneal epithelial cells with the transplanted cells [12]. In case of myocardial regeneration over an area of ischemic or infarcted myocardium, transplantation of a cell sheet not only anatomically covers the surface area of the affected portion but on the other hand, transplantation of dispersed cells alone even when accomplished, retaining them to a certain period until the regeneration of the diseased myocardium may require an additional scaffold to support those cells in place. Such retention scaffolds for dispersed cells become absolutely redundant with this cell-sheet development. Conclusion: Cell sheet engineering technology, developed by a biomaterial scientist has led to successful clinical applications in treating patients with end stage heart-failure and blindness due to corneal epithelial damage as reported by a number of institutes. Their further propagation, after necessary validations, has a potential of providing a solution to multitude of patients suffering from such illnesses. Inter-disciplinary interactions within and across various domains of science as reported here are essential to bring novel solutions in regenerative medicine which is the result of a teamwork among physicians, clinical scientists, cell biologists, biomaterial experts, chemists and physicists. References Yamada, N., Okano, T., Sakai, H., Karikusa, F., Sawasaki, Y. and Sakurai, Y.Thermo-responsive polymeric surfaces; control of attachment and detachment of cultured cells. Makromol. Chem. Rapid Commun. 1990; 11: 571–576. Tang Z, Akiyama Y, Okano T. Temperature-Responsive Polymer Modified Surface for Cell Sheet Engineering. Polymers 2012, 4, 1478-1498. Nichols M, Townsend N, Scarborough P, Rayner M. Cardiovascular disease in Europe 2014: epidemiological update. Eur Heart J. 2014;35(42):2929. Hata H, Matsumiya G, Miyagawa S, Kondoh H, Kawaguchi N, Matsuura N, Shimizu T, Okano T, Matsuda H, Sawa Y. Grafted skeletal myoblast sheets attenuate myocardial remodeling in pacing-induced canine heart failure model. J Thorac Cardiovasc Surg. 2006;132(4):918-24. Sawa Y, Yoshikawa Y, Toda K, Fukushima S, Yamazaki K, Ono M, Sakata Y, Hagiwara N, Kinugawa K, Miyagawa S. Safety and Efficacy of Autologous Skeletal Myoblast Sheets (TCD-51073) for the Treatment of Severe Chronic Heart Failure Due to Ischemic Heart Disease. Circ J. 2015;79(5):991-9. Press Release. Terumo's Autologous Skeletal Myoblast Sheets Are the First to Be Approved as a Cellular or Tissue-based Products in Japan by a Council of the Ministry of Health, Labour and Welfare. http://www.terumo.com/about/pressrelease/2015/20150902.html Whitcher JP, Srinivasan M, Upadhyay MP. Corneal blindness: a global perspective. Bull World Health Organ. 2001;79(3):214-21. Epub 2003 Jul 7. Terry MA. Deep lamellar endothelial keratoplasty (DLEK): pursuing the ideal goals of endothelial replacement. Eye (Lond). 2003 Nov;17(8):982-8. Ramírez BE, Sánchez A, Herreras JM, Fernández I, García-Sancho J, Nieto-Miguel T, Calonge M. Stem Cell Therapy for Corneal Epithelium Regeneration following Good Manufacturing and Clinical Procedures. Biomed Res Int. 2015;2015:408495. Sitalakshmi G, Sudha B, Madhavan HN, Vinay S, Krishnakumar S, Mori Y, Yoshioka H, Abraham S. Ex vivo cultivation of corneal limbal epithelial cells in a thermoreversible polymer (Mebiol Gel) and their transplantation in rabbits: an animal model. Tissue Eng Part A. 2009;15(2):407-15. Nishida K, Yamato M, Hayashida Y, Watanabe K, Yamamoto K, Adachi E, Nagai S, Kikuchi A, Maeda N, Watanabe H, Okano T, Tano Y. Corneal reconstruction with tissue-engineered cell sheets composed of autologous oral mucosal epithelium. N Engl J Med. 2004;351(12):1187-96. Burman S, Sangwan V. Cultivated limbal stem cell transplantation for ocular surface reconstruction. Clin Ophthalmol. 2008;2(3):489-502. About IIDIAS: The Inventions- Inter-Disciplinary Interactions and Solutions (IIDIAS) is an academic session, which is conducted as a part of the one-day International stem cell meet ‘NCRM NICHE’ organized every year in October by the Nichi-In Centre for Regenerative Medicine (NCRM),an Indo-Japan academic Institute based in Chennai, India. In the IIDIAS session, inter-disciplinary interactive research work that are based on the inventions/discoveries in regenerative medicine are presented by relevant experts followed by an interactive session in which the futuristic directions of the accomplishments are discussed. The IIDIAS session 2015 was based on an invention of thermo-responsive polymer cell culture surfaces that has led to successful cell sheet therapy to treat cardiac and corneal diseases.

Background: Original inventions in developing countries, in terms of number of patents filed, granted and that are taken to useful applications as well as in terms of publications of high impact remain relatively lower [1,2] compared to that of developed nations. The reasons could be attributed to lack of importance given to basic research in funding, the number of institutes involved, limited technical support or expertise available etc [1]. Though such initiatives may take a long time to yield fruits, one of the parallel steps we considered worth was to take the original inventions from Japan, born out of basic research in one field, taken through an application-oriented inter disciplinary interactive research in healthcare, thereby paving way for novel solutions. Thus was conceived, the Inventions- Inter-Disciplinary Interactions and Solutions (IIDIAS), an academic session as a part of the one-day International stem cell meet organized every year in the month of October by Nichi-In Centre for Regenerative Medicine (NCRM), an academic Institute based in Chennai, India. In the IIDIAS session, based on original invention(s) presented as a prelude in brief, original interdisciplinary interactive research work based on the original invention by NCRM and/or its collaborators are presented by the faculty of the relevant institute. That will be followed by an interactive session in which the potential solutions based on the above accomplishments would be discussed. The IIDIAS session 2014 was based on the following two inventions: A bio-film-based biosimilar invented by an electro-physicist A unique polymer invented by a chemical engineer Inventions and Interdisciplinary Interactions: Invention –I: The bio-film-based biosimilar invented by an electro-physicist: An electro physicist with the Kyoto University, Japan, Dr Nobuyuki Yamaji observed during his experiments that plants and mammalian tissues secrete a layer of fluid after getting hit by lightning or electric current [3]. The significance of the secretion was unknown to him. Later when he met his friend, Dr. Sunao Kubota, who was a physician and professor of General Surgery in St. Marianna University, he shared his work and Dr. Kubota began analyzing the nature of the secretions. Dr. Kubota hypothesized that the secretion's role may be to provide a temporary barrier to the entry of pathogens through the area of skin dehiscence caused by the electrical damage, until healing process helps to cover the dehiscence. Then for the next decade Yamaji and Kubota worked to isolate the ingredients of the secretion and they together developed a citric acid-based biosimilar capable of killing a wide range of pathogens which are known to cause common as well as severe infections including nosocomial infections such as MRSA, VRE etc [4] without having to use alcohol-based disinfectants. This biosimilar named as Clinister, had the ability to kill even H5N1 influenza virus and is used in Japan as a spray disinfectant in public places [3]. Inter-Disciplinary-Interaction based on the Invention-I: Evaluation of citric acid-based granules in controlling Chickungunya Virus‏: Clinister has not only been proven as a disinfectant but is also a powerful anti-bacterial and anti-fungal agent that strongly restricts the recurrence of the microbes for a long term. In the present study, Clinister was evaluated for its virostatic efficacy against Chikungunya virus (CHIKV) in vitro for the first time. It showed expressive effect on virus grown in BHK cell cultures by inhibiting the development of virus induced cytopathic effect at an effective concentration of 1.5mg/ml in comparison to 70% ethanol, a common disinfectant. The effects on the virus were further checked by Polymerase Chain Reaction (PCR) at different regular post infective intervals from 0 to 72 hrs. The observations suggested that, other than the anti-microbial activity, Clinister also have specific effect on viruses that may cater the need to prevent the spreading of contagious viruses during epidemics which may occur in the future. However it is essential to study the specific targets of Clinister in viruses at a molecular level, and the same is under progress. Invention – II : A unique polymer invented by a chemical engineer A chemical engineer Prof. Yuichi Mori jointly with polymer scientist Dr Hiroshi Yoshioka developed a thermoreversible polymer (TGP) hydrogel composed of thermoresponsive polymer block [poly (Nisopropylacrylamide- co-n-butyl methacrylate) (poly NIPAAm-co-BMA)] and the hydrophilic polymer block [polyethylene glycol (PEG)] (commercial name :Mebiol gel) [5]. This Mebiol gel provides a suitable in vitro environment enabling culture expansion of cells in the lab without the use of biological components such as amniotic membrane or feeder layers. TGP has been earlier employed for the three-dimensional culture of many cell types like corneal limbal stem cells [6], chondrocytes [7], embryonic stem cells [8], hepatocytes [9], induced pluripotent stem (iPS) cells [8] and bone marrow mononuclear cells [10]. TGP has been used for transportation of corneal endothelial precursor cells over long distances without cool preservation [11], for micro-encapsulation of islet cells [12] and as a wound dressing [13]. TGP has been intralesionally applied along with stem cells in an animal model of spinal cord in injury [10]. TGP is a unique polymer capable of maintaining stem cells in an undifferentiated manner for a longer period of time [14]. It does not affect the gene expression profile [15] and the karyotype of the cells is maintained even after long term culture [16]. The safety and efficacy of TGP as a valuable scaffold material has been established in the various in vitro and translational studies [5]. Inter-Disciplinary-Interaction based on the Invention-II: Mebiol Gel as a 3D scaffold for hepatocytes and viral replication Mebiol Gel was used as a 3D scaffold for growing hepatocyte cell line. Mebiol Gel based hepatocytes had better differentiation and the cells were susceptible to hepatitis C virus replication. The Mebiol Gel based 3D culture system can be used as a better cell culture system for viral studies. Potential Solutions: The works presented in the IIDIAS session have portrayed that original invention in any field when subjected to multi-disciplinary interaction after carefully evaluating the potentials can lead to novel solutions. Though the experts in various disciplines in the reported work have got to interact by chance or due to geographical proximity to each other, when a networking platform to throw such ideas to a forum with mutually rewarding opportunities given for discussion and planning of interactive researches is made possible, novel solutions may not be impossible, if the target platform is well understood within the limitations of each stake holder. Creation of a niche or a suitable environment for such multi disciplinary interaction may prevail and work to its best in a physical state of interaction but advances in information technology has broken the need for such physical interaction among peers to bring out novel solutions. Interactions across specialties in the IIDIAS session help in identifying roles for the invention in other fields which may not be directly related to healthcare. The probable solutions and advantages by combining the electro-physical activity-derived biosimilar and the chemically synthesized polymer described in the study include: A novel platform for in vitro culture of HCV having been described, similar platforms for not so easily cultivable viruses can also be developed. The 3D viral culture technology can be exploited to study the replication process and other intricacies of the virus in in vitro culture. When in vitro expansion of viruses in an appropriate manner becomes feasible, anti-viral agents, either virostatic or virucidal, herbal or synthetic biosimilars can be analysed to come out with effective anti viral agents. A biosimilar-based compound having been proven against Chickungunya virus, the same could be tried against life threatening viruses in appropriate and safe environments. Clinister being a food additive-based material, is considered to be safe to human beings [4] and hence its inclusion as an additive to cell culture medium could be studied further in order to check whether the use of common antibiotics and anti-fungals which may be detrimental to cell growth can be avoided yielding safer anti-bacterial and anti-viral agents for cell culture. Conclusion: Multidisciplinary interaction within and across various domains of science has several potentials in bringing out novel solutions and this has been proven by this study of interaction among physicists, chemists and biologists. The authors recommend that establishment of barrier-free interaction platforms within and among institutes and various specialties at varied stages of research activities as portrayed here like the IIDIAS session to bring about novel solutions such as the ones described in this article. References Sumathipala A, Siribaddana S, Patel V. Under-representation of developing countries in the research literature: ethical issues arising from a survey of five leading medical journals. BMC Med Ethics. 2004;5: E5. The World Bank (2008). Global Economic Prospects 2008: Technology Diffusion in the Developing World. Washington, DC: The World Bank. Retrieved February 18, 2008 from http://siteresources.worldbank.org/INTGEP2008/Resources/complete-report.pdf Abraham S. The "Electric Biology" Duo. Trade Secrets- Nature Biotechnology Blog 2011. Full text can be accessed at http://blogs.nature.com/tradesecrets/2011/12/06/the-electric-biology-duo. Kubota S, Matsuzawa K, Wada M, Yamaji N. Bactericidal Effect of a Disinfectant (Bio Io Nurse) Prepared by Adding Citric Acid and Low Concentration Alcohol to Strongly Acidic Electrolyzed Water. New Food Industry 2008; 50:9. Dedeepiya VD, William JB, Parthiban JKBC, Yoshioka H, Mori Y, Kuroda S, Iwasaki M, Preethy S, Abraham SJK. Scaffolds for Cell Transplantation in Neurology: The Suitability of a Thermoreversible Gelation Polymer—Our Perspectives. Journal of Spinal Surgery 2014;1(1). Sitalakshmi G, Sudha B, Madhavan HN, Vinay S, Krishnakumar S, Mori Y, Yoshioka H, Abraham S. Ex Vivo Cultivation of Corneal Limbal Epithelial Cells in a Thermoreversible Polymer (Mebiol Gel) and Their Transplantation in Rabbits: An Animal Model. Tissue Eng Part A. 2009;15(2):407-15. Yasuda A, Kojima K, Tinsley KW, Yoshioka H, Mori Y, Vacanti CA. In vitro culture of chondrocytes in a novel thermoreversible gelation polymer scaffold containing growth factors. Tissue Eng. 2006;12(5):1237-45. Kataoka K, Huh N. Application of a Thermo-Reversible Gelation Polymer, Mebiol Gel, for Stem Cell Culture and Regenerative Medicine. J Stem Cells Regen Med. 2010 ;6(1); 10-14. Parveen N, Khan AA, Baskar S, Habeeb MA, Babu R, Abraham S, Yoshioka H, Mori Y, Mohammed HC. Intraperitoneal Transplantation of Hepatocytes Embedded in Thermoreversible Gelation Polymer (Mebiol Gel) in Acute Liver Failure Rat Model. Hepatitis Monthly 2008; 8(4): 275-280. William BJ, Prabakaran R, Ayyappan S, Puskhinraj H, Rao D, Manjunath S, Thamaraikannan P, Dedeepiya VD, Kuroda S, Yoshioka H, Mori Y, Preethy, Abraham S. Functional Recovery of Spinal Cord Injury Following Application of Intralesional Bone Marrow Mononuclear Cells Embedded in Polymer Scaffold - Two Year Follow-up in a Canine. J Stem Cell Res Ther.2011; 1:110. Rao SK, Sudhakar J, Parikumar P, Natarajan S, Insaan A, Yoshioka H, Mori Y, Tsukahara S, Baskar S, Manjunath SR, Senthilkumar R, Thamaraikannan P, Srinivasan T, Preethy S, Abraham SJ. Successful transportation of human corneal endothelial tissues without cool preservation in varying Indian tropical climatic conditions and in vitro cell expansion using a novel polymer. Indian J Ophthalmol. 2014;62(2):130-5. Shimizu S, Yamazaki M, Kubota S, Ozasa T, Moriya H, Kobayashi K, Mikami M, Mori Y, Yamaguchi S. In vitro studies on a new method for islet microencapsulation using a thermoreversible gelation polymer, N-isopropylacrylamide-based copolymer. Artif Organs. 1996;20(11):1232-7. Yoshioka H, Mori Y, Kubota S. Wound dressing of newly developed thermogelling thermoreversible hydrogel. Jpn J Artif Organs. 1998; 27: 503-506. Arumugam S, Manjunath S , Senthilkumar R, Srinivasan V, Rajendiran S, Yoshioka H, Mori Y, Abraham S. In vitro expansion and characterization of human chondrocytes using a novel Thermoreversible Gelation Polymer (TGP). Journal of orthopaedics. 2011; 8(3); 1-10. Hishikawa K, Miura S, Marumo T, Yoshioka H, Mori Y, Takato T, Fujita T. Gene expression profile of human mesenchymal stem cells during osteogenesis in three-dimensional thermoreversible gelation polymer. Biochem Biophys Res Commun. 2004;317(4):1103-7. Lei Y, Schaffer DV. A fully defined and scalable 3D culture system for human pluripotent stem cell expansion and differentiation. Proc Natl Acad Sci U S A. 2013;110(52):E5039-48.

Senthilkumar Preethy,1,2 Sudhakar John,1 Jegatheesan Saravana Ganesh,1 Thangavelu Srinivasan,1 Hiroshi Terunuma,3 Masaru Iwasaki,4 Samuel J Abraham1,4 1Nichi-In Centre for Regenerative Medicine, 2Hope Foundation Trust, Chennai, India; 3Biotherapy Institute of Japan, Tokyo, 4Yamanashi University School of Medicine, Chuo, Japan Abstract: Among the various strategies providing a cure for illness, cell-based therapies have caught the attention of the world with the advent of the "stem cell" era. Our inherent understanding indicates that stem cells have been in existence since the birth of multicellular organisms. However, the formal discovery of stem cells in the last century, followed by their intricate and extensive analysis, has led to clinical and translational efforts with the aim of using them in the treatment of conditions which don't have a definitive therapeutic strategy, has fueled our interest and expectations. Technological advances in our ability to study their cellular components in depth, along with surface markers and other finer constituents, that were unknown until last century, have improved our understanding, leading to several novel applications. This has created a need to establish guidelines, and in that process, there are expressed understandings and views which describe cell therapy along lines similar to that of biologic products, drugs, and devices. However, the age-old wisdom of using cells as tools for curing illness should not be misled by recent knowledge, to make cell therapy using highly complex stem cells equal to factory-synthesized and reproducible chemical compounds, drugs, or devices. This article analyses the differences between these two entities from various perspectives. Keywords: cell transplantation, drugs, regenerative medicine, stem cells

Objectives: Type A aortic dissection (ATAAD) is hypothesised as a progression of aneurysmal dilation, but 60% of patients in the International Registry of Acute Aortic Dissection (iRAD) registry had a maximum aortic diameter (MAD)<55 mm. We aim to demonstrate that size ratios and aortic wall stress, assessed using a simplified markers, are unique to aortic patients who have had adverse events (ATAAD) compared to those who have not (thoracic aortic aneurysm [TAA])., Methods: A retrospective cohort analysis of patients who underwent aortic intervention at Waikato Hospital, New Zealand between 2015-2020, comparing dissection (ATAAD) to TAA patients. MAD; ratio of MAD to standardised-points within the aorta; and MAD-to-height collected from computed tomography (CT)-scans of all patients was undertaken. Receiver operating characteristic (ROC)-analysis to determine cut-off point for each marker was undertaken together with multivariable logistic regression comparing both cohorts, cross-validated by propensity-score matched analysis., Results: Cohort of 215 patients, 78 (36.3%) ATAAD and 137 (63.7%) TAA; median age at intervention 63.3 years, 52 (24.2%) females, both cohorts matched for size. Using the entire cohort, the MAD: sinus of Valsalva (SoV) ratio>1.06 (cut-off value) had 4.5-times greater association with ATAAD (95%CI 1.46-13.8) and a 0.1-unit increased conferred 1.45-times greater association with ATAAD (95%CI 1.00-2.08). MAD>55 mm only seen in 33.3% of ATAAD (n=26/78), and not associated with ATAAD (OR 1.88, 95%CI 0.64-5.51). Compared to MAD, MAD:SoV ratio had greater sensitivity (33% vs 73%), lower number-needed-to-treat (17.9 vs 2.7) and superior discrimination (area under the curve [AUC] 0.54 vs 0.71). Findings were consistent with propensity score matched analysis., Conclusions: MAD:SoV ratio significantly correlates with ATAAD (4.5 times), with superior sensitivity, discrimination, and attributable-risk-percentage compared to MAD alone., Competing Interests: Conflict of Interest None declared., (Crown Copyright © 2022. Published by Elsevier B.V. All rights reserved.)

Background: Simulation training is a useful adjunct to surgical training and education (SET) in Cardiothoracic Surgery yet training opportunities outside the Royal Australasian College of Surgery or industry-sponsored workshops are rare due to high cost and limited training faculty, time, assessment tools or structured curricula. We describe our experience in establishing a low-cost cardiac simulation programme., Methods: We created low-cost models using hospital facilities, hardware stores, abattoirs and donations from industry. Three workshops were conducted on coronary anastomoses, aortic and mitral valve replacement., Results: Whole porcine hearts were sourced from local farms. Industry donations of obsolete stock were used for suture and valve material-stations constructed using ironing-board, 2-L buckets and kebab-skewers. Suture ring holders were fashioned from recycled cardboard or donated. All participants were asked to complete pre and post simulation self-assessment forms. Across three workshops, 45 participants (57.8% female) with a median age 27 (interquartile range 24-31) attended. Training level consisted of nurses (8, 17.8%), medical students (17, 37.8%), residents/house officers (6, 13.3%) and registrars (14, 31.1%). There were improvements in knowledge of anatomy (mean difference 18%; 95% confidence interval 12%-24%), imaging (16%; 10%-22%) and procedural components (34%; 28%-42%); and practical ability to describe steps (30%; 24%-38%), partially (32%; 26%-38%) or fully complete (32%; 28%-38%) the procedure., Conclusions: Simulation-based training in cardiac surgery is feasible in a hospital setting with low overhead costs. It can benefit participants at all training levels and has the potential to be implemented in training hospitals as an adjunct to the SET programme., (© 2021 Royal Australasian College of Surgeons.)

COronaVIrus Disease 2019 (COVID-19) is an on-going pandemic attributed to a novel virus named SARS-CoV-2. Comparing the statistics of incidence and death rates between nations reveals that there is discrepancy amongst countries in these regards, even between countries that share borders. We herein present information from the literature indicating how cross-protection against COVID-19 conferred by the encephalitis vaccine could be the reason for lower fatality rate in the countries where immunization against encephalitis is widespread or included in national programs. This may pave the way for arriving at efficient prevention strategies as well as vaccine development.

A series of ferulic acid (FA) derivatives were synthesized and evaluated for its ability to inhibit NorA efflux in methicillin resistant Staphylococcus aureus (MRSA), by in silico docking analysis. Based on prediction from glide scores and ability to reduce EtBr MIC, two of the ten derivatives S3- [4-((E)-2-(diethylcarbamoyl)vinyl)-2-methoxyphenyl acetate] and S6- [(E)-methyl 3-(4-((p-tolylcarbamoyl)methoxy)-3-methoxyphenyl)acrylate] were chosen as putative efflux pump inhibitors (EPI's). Time dependent accumulation studies revealed that S6 caused enhanced EtBr accumulation relative to standard NorA efflux inhibitor reserpine, in clinical isolate of MRSA (CIMRSA) and in NorA overexpressed strain of S. aureus (SA1199B). S6 also exhibited synergy with Ciprofloxacin (CPX) against NorA overexpressed strain (SA1199B) of S. aureus but not in NorA knock out strain (K1758). MIC reversal studies showed that S3 in CIMRSA and S6 in NorA overexpressed strain of S. aureus (SA1199B), caused a 4 fold reduction in CPX MIC. In vitro time kill studies revealed that both S3 and S6 with sub MIC of CPX caused a significant 4 log CFU decline in CIMRSA. A decline of >3 log fold CFU by time kill assay implies synergy between FA derivatives and CPX. When tested in vivo in infected muscle tissue of zebrafish both S3 and S6 with CPX caused >3.2 log decline in CIMRSA cell counts relative to CPX treatment alone. Of the two potent derivatives, S6 probably acts through NorA whereas S3 might exert its effect through pump other than NorA. Greater in vitro and in vivo efficiency of FA derivatives implies its potential to be used as an adjuvant along with CPX to curtail MRSA infection in higher animal models., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Dyslipidemia is a major risk factor for the development of cardiovascular diseases and statins are the common drugs used to correct dyslipidemia. Herein, we report a case where the subject was a nondiabetic, dyslipidemia patient on medication with Rosuvastatin. After the intake of Rosuvastatin, his triglycerides decreased to a minimum of 220 mg/dL. In order to augment the action of Rosuvastatin, he was advised to take 1.5 mg of Nichi Glucan food supplement, which is a 1,3-1,6 Beta Glucan derived from the black yeast, Aureobasidium pullulans, daily for 2 months. At the end of 2 months, his triglyceride levels decreased from 523 mg/dL (at start of the study) to 175 mg/dL. His VLDL levels, which were 104.6 mg/dL at the start of the study decreased to 35 mg/dL and the HDL cholesterol levels increased from 27 to 38 mg/dL. This is a first of its kind report on the effect of the black yeast derived 1,3-1,6 Beta Glucans on dyslipidemia not associated with diabetes. Thus supplementation of Nichi Glucan, 1,3- 1,6 Beta Glucan derived from the black yeast along with the routine medications was beneficial to treat dyslipidemia and a larger trial is needed to confirm the effects.

The optimal myocardial protection method for aortic valve replacement in the setting of prior coronary artery bypass surgery remains a subject of debate. Protection is particularly challenging when a patent pedicled internal thoracic artery graft supplies a proximally obstructed left anterior descending artery. Herein, we describe a modification of an old technique; continuous coronary perfusion, which can be used in selected, anatomically suitable cases.

Objective: Cardiac troponin-I (cTnI) levels in the potential heart transplant donor may be a marker of heart dysfunction and predictive of recipient outcome. We studied the prevalence of cTnI elevation, its association with heart function and usability and its relationship with the time duration from coning., Methods: In a prospective study, cTnI measurement, Swan-Ganz catheterisation and transthoracic echocardiography were performed at initial assessment in 79 potential heart donors (mean age 43 +/- 13.1 years). All donors were then managed according to a strict algorithm to optimise cardiac function, some receiving hormonal therapy as part of a randomised trial. Donor heart suitability for transplantation was assessed after 7 h of management. The association of cTnI with initial functional indices was assessed and outcome compared for donors categorised according to cTnI level < or = 1 microg l(-1) or >1 microg l(-1)., Results: Serum cTnI levels negatively correlated with initial cardiac index (CI) (p = 0.003), right (p < 0.001) and left ventricular ejection fraction (p = 0.001) and positively with LV Tei index (p = 0.003). Serum cTnI was >1 microg l(-1) in 29/79 donors. Higher CVP (10 +/- 5.1 vs 7.9 +/- 2.9; p = 0.026) and PAWP (12 +/- 5.4 vs 8.1 +/- 3.1; p = 0.002), lower cardiac index (2.7 +/- 1.1 vs 3.6 +/- 0.9; p = 0.001) and fractional shortening (p < 0.01) and worse wall motion score index (p < 0.01) were observed in the cTnI >1 microg l(-1) group. CTnI and functional markers correlated with the time duration from coning., Conclusion: The donor cTnI level represents a biochemical surrogate of functional donor heart assessment. High cTnI is associated with worse donor heart function and may act as a prompt for detailed assessment and optimisation.

Objective: Despite 50 years of lung preservation research, the optimal preservation technique is undefined. Using data from a national cohort, we investigated outcomes with different preservation methods after adult lung transplantation., Methods: Early (30-day), late (30-day to 3-year), and overall (3-year) mortalities, adjusted for differences in donor and recipient characteristics, were compared by using Cox regression. Intensive care unit length of stay and the number of rejection episodes were secondary outcomes., Results: Six hundred eighty-one eligible lung transplantations between July 1995 and June 2003 were preserved with Euro-Collins solution (n = 284), blood albumin (n = 139), core cooling (n = 107), or low potassium dextran solution (n = 151). There was significantly increased use of low potassium dextran solution over time (P < .001). Unadjusted 3-year survival was similar across the groups (P = .72), with the highest 3-year survival in the low potassium dextran group (62%; 95% confidence interval, 51%-72%) and the lowest in the blood albumin group (49%; 95% confidence interval, 39%-58%). Risk-adjusted early (P = .70), late (P = .27), and overall (P = .72) survival was similar across the groups and was not affected by ischemic time. Freedom from death caused by primary graft dysfunction was again highest in the low potassium dextran group (95%; 95% confidence interval, 90%-98%) and lowest in the blood albumin group (91%; 95% confidence interval, 85%-95%). There was no difference in intensive care unit length of stay. An increased incidence of rejection was apparent with increasing ischemic time (P = .067)., Conclusion: The methods of lung preservation in current use do not seem to affect early or midterm survival after transplantation, but increasing ischemic time might predispose to increased rejection.

Background: The influence of donor cause of death (DCD) on survival after lung transplantation (LTx) is uncertain. This was investigated using data from a national prospective cohort study of adult single and bilateral LTx undertaken between July 1995 and June 2002., Methods: DCD was categorized a priori into vascular and tumor (V), traumatic (T), hypoxic brain damage (H) and infective (I) causes. All T donor deaths were the result of blunt trauma. Risk factors for early (30 days), late (30 days to 5 years) and overall (5 years) mortality were identified using Cox regression analysis., Results: Of 580 eligible transplants, DCDs were classified as V (n = 372), T (n = 153), H (n = 38) and I (n = 17). V donors were older (median 42 years) than the others (medians < 27 years) (p < 0.001). T donors were more likely to be of male gender (p < 0.001). Two hundred fifty-nine patients died within 5 years of surgery. The median follow-up time of survivors was 37 months. Unadjusted 5-year Kaplan-Meier survival rates did not vary with DCD (p = 0.6). Cox analysis identified donor age group, recipient diagnosis, pre-operative recipient ventilation, donor-recipient size mismatch, donor-recipient blood group variance, cytomegalovirus (CMV) mismatch and recipient creatinine clearance as predictors of mortality. After adjustment for these risk factors, DCD was not identified as a predictor of early (p = 0.2), late (p = 0.5) or overall mortality (p = 0.4) in LTx recipients., Conclusion: We found that DCD did not affect mid-term survival after LTx.

Objective: Guidelines are needed for real-time quality monitoring in heart and lung transplantation. The cumulative sum (CUSUM) methodology with boundary limits derived from the sequential probability ratio test (SPRT) provide a means of monitoring performance without the need for repeated statistical testing. The variable life adjusted display (VLAD) complements the SPRT chart and provides a directly interpretable assessment of performance. We present our experience with these charts in monitoring cardiothoracic transplant outcomes in the UK., Methods: Thirty-day-post-transplantation mortality after isolated first time transplantation of the heart (n=1634) or lung (n=1162) in adults, between July 1995 and March 2004 in eight centres were monitored. CUSUM charts, with and without risk-adjustment and risk-adjusted VLAD plots were constructed. Thirty-day mortality rates for the UK as a whole were taken as the reference values for the unadjusted charts and a 50% increase in risk provided the basis for construction of boundary lines for the SPRT. Risk-adjustment was based on multivariate models previously developed from the national database., Results: For heart transplantation without risk-adjustment, four centres crossed the lower boundary, indicating 30-day mortality was in-line with or better than seen nationally. Two centres were close to signalling an alert, warning of a rise in mortality rate, but neither chart signalled an alarm. After risk-adjustment one centre's graph moved towards the centre of the chart, indicating monitoring should continue and the other signalled an alarm. For lung transplantation the unadjusted mortality rate at one centre was confirmed acceptable and the results remained inconclusive for five. At the other centre, following an alert to a possible increase in mortality half-way through the sequence, results improved. Case-mix adjustment served to pull the charts away from the upper boundary lines; no chart suggested any cause for concern. For most centres the VLAD charts oscillated around the horizontal axis., Conclusions: CUSUM charts are useful tools for monitoring performance, and provide a basis for visually comparing results between centres and identifying periods of 'bad runs'. Risk-adjustment, which down-weights higher risk activity, avoids inappropriate reaction to unadjusted breaches of alert and alarm lines.

Cystic fibrosis (CF) patients requiring transplantation for respiratory failure may undergo either heart-lung (HLT) or bilateral sequential lung (BSLT) transplantation. The choice of operation varies between surgeons, centres and countries. The current authors investigated whether operation type influenced outcome in adult CF patients transplanted in the UK between July 1995 and June 2002. Propensity scores for receipt of BSLT versus HLT were derived using logistic regression. Cox regression was used to compare survival. In total, 88 BSLTs and 93 HLTs were identified. Patient characteristics were similar overall, but HLT recipients were more likely to be on long-term oxygen therapy and to have had prior resuscitation. There were 72 deaths (29 BSLT and 43 HLT) within 4 yrs. There was a trend towards higher unadjusted survival following BSLT, but, after adjustment, no difference was found (hazard ratio = 0.77; 95% confidence interval 0.29-2.06). Time to the first rejection episode and infection rates were also similar. A total of 82% of hearts from HLT recipients were used as domino heart transplants. In conclusion, after adjusting for comorbidity, donor factors and ischaemia time, it was found that heart-lung and bilateral sequential lung transplantation achieved a similar outcome. The use of domino heart transplantation ameliorated the impact of heart-lung transplantation on total organ availability.

Objective: Donor cause of death may be a risk factor for early mortality after heart transplantation, but its effect on medium-term survival is uncertain., Methods: By means of a national prospective database, we investigated the influence of donor cause of death on survival to 3 years in 1254 adult recipients of cadaveric heart transplantation between July 1995 and June 2002. Donor cause of death was categorized a priori as vascular and tumor (group V, n = 739), trauma (group T, n = 407), hypoxic (group H, n = 82), and infective causes (group I, n = 26). Risk factors for early (30-day), late (30-day to 3-year), and overall mortality were identified with Cox regression., Results: Group V donors were more likely to be older ( P < .001) and female ( P < .001). There were 297 deaths in the 3-year period, and the unadjusted 3-year survivals varied significantly (group V 73%, group T 79%, group H 85%, group I 80%, P = .01). Cox analysis identified donor age, organ ischemia time, recipient creatinine clearance, recipient diagnosis, peripheral vascular disease, ventilation, diabetes, and donor-recipient size mismatch as risk factors for early, late, or overall mortality ( P < .10). After adjustment for these factors, donor cause of death was no longer a significant predictor of recipient death (early death P = .36, late death P = .79, overall mortality P = .37)., Conclusion: We confirmed that there is an apparent association between cause of donor death and posttransplantation survival, but this was not maintained after adjustment for confounding variables. Donor cause of death therefore should not influence donor organ acceptance or donor-recipient matching and does not identify marginal donors.