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Alberti C, Tizzani A, Piovano M, Greco A. What's in the Pipeline about Bladder Reconstructive Surgery? Some Remarks on the State of the Art. Int J Artif Organs 2018; 27:737-43. [PMID: 15521212 DOI: 10.1177/039139880402700902] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The fusion of engineering with cell biology and advances in biomaterials may lead to de novo construction of implantable organs. Engineering of neobladder from autologous urothelial and smooth muscle cells cultured on biocompatible, either synthetic or naturally-derived substrates, is now feasible in preclinical studies and may have clinical applicability in the near future. The development of a bioartificial bladder would warrant the prevention of both the metabolic and neoplastic shortcomings of the intestinal neobladder. Two tissue-engineering techniques for bladder reconstruction have been tested on animals: 1) the in vivo technique involves the use of naturally-derived biomaterials for functional native bladder regeneration 2) the in vitro technique involves the establishment of autologous urothelial and smooth muscle cell culture from the host's urinary tract, after which the cells are seeded on the biodegradable matrix-scaffold to create a composite graft that is implanted into the same host for complete histotectonic regeneration. Waiting for the creation of a complete tissue-engineered bladder with a trigone-shaped base, we suggest, in surgical oncology after radical cystectomy, the realization of conduit or continent pouch using tissue-engineered material.
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Affiliation(s)
- C Alberti
- I Clinical Urology, University of Turin, Turin, Italy
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Zambon JP, Magalhaes RS, Ko I, Ross CL, Orlando G, Peloso A, Atala A, Yoo JJ. Kidney regeneration: Where we are and future perspectives. World J Nephrol 2014; 3:24-30. [PMID: 25332894 PMCID: PMC4202490 DOI: 10.5527/wjn.v3.i3.24] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/18/2014] [Revised: 06/27/2014] [Accepted: 07/29/2014] [Indexed: 02/06/2023] Open
Abstract
In 2012, about 16487 people received kidney transplants in the United States, whereas 95022 candidates were on the waiting list by the end of the year. Despite advances in renal transplant immunology, approximately 40% of recipients will die or lose graft within 10 years. The limitations of current therapies for renal failure have led researchers to explore the development of modalities that could improve, restore, or replace the renal function. The aim of this paper is to describe a reasonable approach for kidney regeneration and review the current literature regarding cell sources and mechanisms to develop a bioengineering kidney. Due to kidneys peculiar anatomy, extracellular matrix based scaffolds are rational starting point for their regeneration. The perfusion of detergents through the kidney vasculature is an efficient method for delivering decellularizing agents to cells and for removing of cellular material from the tissue. Many efforts have focused on the search of a reliable cell source to provide enrichment for achieving stable renal cell systems. For an efficient bioengineered kidney, these cells must be attached to the organ and then maturated into the bioractors, which simulates the human body environment. A functional bioengineered kidney is still a big challenge for scientists. In the last ten years we have got many improvements on the field of solid organ regeneration; however, we are still far away from the main target. Currently, regenerative centers worldwide have been striving to find feasible strategies to develop bioengineered kidneys. Cell-scaffold technology gives hope to end-stage renal disease patients who struggle with morbidity and mortality due to extended periods on dialysis or immunosupression. The potential of bioengineered organ is to provide a reliable source of organs, which can be refunctionalized and transplanted.
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Nieponice A, Ciotola FF, Nachman F, Jobe BA, Hoppo T, Londono R, Badylak S, Badaloni AE. Patch esophagoplasty: esophageal reconstruction using biologic scaffolds. Ann Thorac Surg 2013; 97:283-8. [PMID: 24266951 DOI: 10.1016/j.athoracsur.2013.08.011] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/11/2013] [Revised: 08/06/2013] [Accepted: 08/07/2013] [Indexed: 12/19/2022]
Abstract
BACKGROUND Standard techniques for surgical reconstruction of the esophagus remain suboptimal. Primary closure of diseased or injured esophagus has been associated with high morbidity, primarily due to leak and stricture, and synthetic materials are contraindicated due to the high risk of erosion and infection. Degradable bioscaffolds composed of extracellular matrix (ECM) have recently shown promising results in both pre-clinical and clinical settings to prevent stricture after extended endoscopic mucosal resection. We propose a novel surgical technique that utilizes an ECM scaffold as a reconstructive patch to augment the esophageal diameter during primary repair. METHODS Four patients requiring esophageal reconstruction underwent a patch esophagoplasty using an ECM scaffold composed of porcine urinary bladder ECM. The full thickness wall of the esophagus was replaced with an ECM patch that was sutured to the edges of the remaining esophagus, similar to the patch angioplasty performed in vascular procedures. RESULTS All patients had a favorable clinical outcome with immediate recovery from the procedure and reinstated oral intake after 7 days. One patient had a micro leak at day 5 that closed spontaneously 2 days after drainage. Follow-up studies including barium swallow and esophagogastroduodenoscopy (EGD) showed adequate esophageal emptying through the surgical segment in all patients. The EGD showed complete mucosal remodeling at 2 months, with approximately 20% area contraction at the patch level. The area of the defect was indistinguishable from surrounding healthy tissue. Biopsy of the patch area showed normal squamous epithelium. One of the patients had a separate intrathoracic stricture that required further surgery. Clinical outcomes were otherwise favorable in all cases. CONCLUSIONS An alternative for the treatment of esophageal stenosis is presented which uses a biological scaffold and an innovative surgical procedure. Additional work, including prospective studies and long-term follow-up, is required to fully evaluate the potential of this bioscaffold-based regenerative medicine approach for esophageal reconstruction.
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Affiliation(s)
- Alejandro Nieponice
- Esophageal Surgery Program, University of Favaloro, Buenos Aires, Argentina; McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania.
| | - Franco F Ciotola
- Esophageal Surgery Program, University of Favaloro, Buenos Aires, Argentina
| | - Fabio Nachman
- Esophageal Surgery Program, University of Favaloro, Buenos Aires, Argentina
| | - Blair A Jobe
- McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Toshitaka Hoppo
- McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Ricardo Londono
- McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Stephen Badylak
- McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Adolfo E Badaloni
- Esophageal Surgery Program, University of Favaloro, Buenos Aires, Argentina
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Chatterjee US, Chatterjee SK. Regenerative urethroplasty in reoperative hypospadias: Buried strip principle revisited. J Indian Assoc Pediatr Surg 2012; 17:63-7. [PMID: 22529550 PMCID: PMC3326824 DOI: 10.4103/0971-9261.93965] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Aim: Reporting the feasibility of the Denis Browne (buried strip) principle along with tunica vaginalis (TV) pedicled wrapping of the strip in reoperative urethroplasty in hypospadias. Materials and Methods: Over a period of 5 years, 32 patients presented with failure of previous urethroplasty and the range of failure was between 2 and 6 times; mean 2.5 times. Mean age was 12.9 (range 2 to 26 years) years. “Buried strip” urethroplasty (i.e., without tubularization of urethral plate) and wrapping with TV were done along with supra pubic cystostomy (SPC) for diversion of urine. Mean follow-up was 29.8 (range 12 to 56 months) months. Results: One patient had fistula and vertical slit meatus was possible in 26 patients. The flow of urine was satisfactory in 31 patients and one patient developed pouch in penile urethra. Conclusions: The buried strip along with the additional coverage with TV was found to be simple and effective in salvaging the failed urethroplasty.
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Affiliation(s)
- Uday S Chatterjee
- Department of Pediatric Surgery, Park Medical Research and Welfare Society, Kolkata, India
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Lu SH, Wei CF, Yang AH, Chancellor MB, Wang LS, Chen KK. Isolation and characterization of human muscle-derived cells. Urology 2009; 74:440-5. [PMID: 19362337 DOI: 10.1016/j.urology.2009.01.048] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2008] [Revised: 12/21/2008] [Accepted: 01/27/2009] [Indexed: 11/16/2022]
Abstract
OBJECTIVES To isolate and characterize human muscle-derived cells (MDCs) for future management applications on lower urinary tract symptoms, including stress urinary incontinence and bladder reconstitution. The development of muscle stem cells for transplantation or gene transfer in patients with muscle disorders has become more attractive and challenging recently. METHODS Human MDCs were isolated from the skeletal muscles of the limbs. The muscle tissues were minced, digested at 37 degrees C by 0.2% collagenase, trypsinized, filtered, and cultured in F12 medium with 15% fetal bovine serum at 37 degrees C. Human MDCs were then isolated using a modified preplate technique. After isolation, the MDCs were characterized by immunohistochemistry, flow cytometry, and indirect immunofluorescence. RESULTS The growth doubling time of the MDCs was approximately 24 hours. Immunohistochemistry study was performed with the stem cell markers CD34, CD117, vascular cell adhesion molecule, and vascular endothelial growth factor receptor 2, and the relative stem cell position was identified. Positive immunofluorescence outcomes were found with the stem cell markers, myoblast markers CXCR4, CD56, desmin, and a fibroblast marker AB-1. Flow cytometry analysis identified markers CD34 and CD56 in the isolated MDCs, with a percentage of 5.12% and 10.34%, respectively. CONCLUSIONS The isolation and characterization of human MDCs was successfully achieved. Human MDCs might have the potential to be a novel tool for the management of stress urinary incontinence and bladder reconstitution.
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Affiliation(s)
- Shing-Hwa Lu
- Department of Urology, National Yang-Ming University School of Medicine, Taipei, Taiwan.
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Jahan-Parwar B, Chhetri DK, Ye M, Hart S, Berke GS. Hylan B Gel Restores Structure and Function to Laser-Ablated Canine Vocal Folds. Ann Otol Rhinol Laryngol 2008; 117:703-7. [DOI: 10.1177/000348940811700913] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Objectives: We evaluated cross-linked hyaluronic acid (hylan B gel) as a scaffold for tissue regeneration and mucosal wave restoration in carbon dioxide laser–ablated canine vocal folds. Methods: Five beagles underwent stroboscopy before ablation of the left vocal fold with a carbon dioxide laser. Four weeks later, stroboscopy was repeated before and after submucosal injection of hylan B gel into the left vocal fold of 4 animals and of saline solution in 1 animal. Stroboscopy was repeated 12 weeks later, and histologic analysis was performed. Results: Four weeks after laser ablation, all animals had soft tissue defects and absence of mucosal waves. Hylan B injection restored mucosal waves, and saline injection did not. Twelve weeks after injection, hylan B–injected larynges had tissue regeneration and mucosal waves, and the saline-injected larynx had neither. Histology showed regenerated lamina propria with residual foci of hylan B in the hylan B–injected larynges and dense submucosal scar in the saline-injected animal. Conclusions: Submucosal hylan B gel injection in laser-ablated canine vocal folds restored tissue volume and mucosal waves and facilitated functional tissue regeneration over 12 weeks. Hylan B gel may have utility as a soft tissue scaffold for rehabilitation of phonatory function in vocal folds with lamina propria defects.
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Aboushwareb T, Egydio F, Straker L, Gyabaah K, Atala A, Yoo JJ. Erythropoietin producing cells for potential cell therapy. World J Urol 2008; 26:295-300. [DOI: 10.1007/s00345-008-0301-0] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2008] [Accepted: 06/09/2008] [Indexed: 12/01/2022] Open
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Leriche A, Timsit MO, Morel-Journel N, Bouillot A, Dembele D, Ruffion A. Long-term outcome of forearm flee-flap phalloplasty in the treatment of transsexualism. BJU Int 2008; 101:1297-300. [PMID: 18190640 DOI: 10.1111/j.1464-410x.2007.07362.x] [Citation(s) in RCA: 103] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
OBJECTIVE To assess the long-term outcome of forearm free-flap phalloplasty in transsexuals, as obtaining a satisfying neophallus in female-to-male transsexuals is a surgical challenge. PATIENTS AND METHODS We analysed retrospectively 56 transsexuals who had a phalloplasty using a radial forearm free-flap in our department from 1986 to 2002. The complication rate was assessed by regular examination. Patient satisfaction was evaluated by a questionnaire about cosmetic aspects, sexual life and overall satisfaction. RESULTS The mean follow up was 110 months; 53 of the 56 patients (95%) currently have a neophallus, after a mean of six surgical procedures. Satisfaction was assessed in 53 patients using a specific questionnaire: 51 (93%) of the patients reported that the phalloplasty allowed them to accord their physical appearance with their feeling of masculinity. There were flap complications in 14 patients (25%); three (5%) flaps were lost, with one each due to early haematoma, cellulitis and late arterial thrombosis. The other 11 flap complications were all transitory, e.g. infection, haematomas and vascular thrombosis. There were prosthesis complications in 11 of 38 patients (29%). Moreover, seven of 19 patients (37%) who had a urethroplasty presented with complex strictures and fistulae that led to perineal urethrostomy. CONCLUSION Our study shows that phalloplasty with a forearm free-flap leads to good results in term of flap survival and patient satisfaction. However, there was a high rate of complications. Patients must be clearly informed that the procedure can seldom be achieved in one stage.
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Affiliation(s)
- Albert Leriche
- Department of Urology, Henry Gabrielle Hospital, University of Lyon I, Lyon, France
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Roelofs LA, Eggink AJ, Hulsbergen-van de Kaa CA, Wijnen RM, van Kuppevelt TH, van Moerkerk HT, Crevels AJ, Hanssen A, Lotgering FK, van den Berg PP, Feitz WF. Fetal Bladder Wall Regeneration with a Collagen Biomatrix and Histological Evaluation of Bladder Exstrophy in a Fetal Sheep Model. Fetal Diagn Ther 2008; 24:7-14. [DOI: 10.1159/000132399] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2007] [Accepted: 02/02/2007] [Indexed: 11/19/2022]
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Schultheiss D, Jonas U. [Regenerative medicine in andrology: tissue engineering and gene therapy as potential treatment options for penile deformations and erectile dysfunction]. Actas Urol Esp 2006; 30:801-11. [PMID: 17078577 DOI: 10.1016/s0210-4806(06)73537-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Tissue engineering and gene therapy are currently investigated in animal studies for reconstructing penile tissue or treating erectile dysfunction. This review aims to ecamine these experimental efforts from the last years and tries to give a brief introduction to the basic methodology of these new techniques from the field of regenerative medicine.
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Affiliation(s)
- D Schultheiss
- Servicio de Urología y Urología Pediátrica, Red de Ingeniería Tisular, Facultad de Medicina de Hannover, Alemania.
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Geutjes PJ, Daamen WF, Buma P, Feitz WF, Faraj KA, van Kuppevelt TH. From Molecules to Matrix: Construction and Evaluation of Molecularly Defined Bioscaffolds. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2006; 585:279-95. [PMID: 17120791 DOI: 10.1007/978-0-387-34133-0_19] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
In this chapter, we describe the fundamental aspects of the preparation of molecularly-defined scaffolds for soft tissue engineering, including the tissue response to the scaffolds after implantation. In particular, scaffolds prepared from insoluble type I collagen fibres, soluble type II collagen fibres, insoluble elastin fibres, glycosaminoglycans (GAGs) and growth factors are discussed. The general strategy is to prepare tailor-made "smart" biomaterials which will create a specific microenvironment thus enabling cells to generate new tissues. As an initial step, all biomolecules used were purified to homogeneity. Next, porous scaffolds were prepared using freezing and lyophilisation, and these scaffolds were crosslinked using carbodiimides. Crosslinking resulted in mechanically stronger scaffolds and allowed the covalent incorporation of GAGs. Scaffold characteristics were controlled to prepare tailor-made scaffolds by varying e.g. collagen to elastin ratio, freezing rate, degree of crosslinking, and GAGs attachment. The tissue response to scaffolds was evaluated following subcutaneous implantations in rats. Crosslinked scaffolds maintained their integrity and supported the formation of new extracellular matrix. Collagen-GAG scaffolds loaded with basic fibroblast growth factor significantly enhanced neovascularisation and tissue remodelling. Animal studies of two potential applications of these scaffolds were discussed in more detail, i.e. for bladder and cartilage regeneration.
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Affiliation(s)
- Paul J Geutjes
- Radboud University Nijmegen Medical Centre, Department of Biochemistry, P.O. Box 9101, 6500 HB Nijmegen, The Netherlands
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De Diego Rodríguez E, Villanueva Peña A, Roca Edreira A, Martín García B, Meana Infiesta A, Gómez Llames S. [Current status of tissue engineering in urology. Review of the literature]. Actas Urol Esp 2005; 28:636-45. [PMID: 16050197 DOI: 10.1016/s0210-4806(04)73154-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
In the eighties a new field of the medicine appears wich applies the principles of cellular cultivation to synthetic biodegradable polymers scaffolds with the purpose of creating autologous biological substitutes that could improve, maintain or restore the function of organs or damaged tissues. The Tissue Engineering constitutes a new discipline in full phase of development especially in USA, with multiple potential applications in several medical specialities. Our speciality can't remain indifferent to interest and encouraging future originated by this new science. In this work we have made a wide bibliographical revision in the Medline to know the antecedents, current state and the possible future applications of Tissue Engineering in Urology.
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Alberti C, Mediago M, Chiapello G, Arena G. Tissue Engineering in Urology: Between Basic Research and Clinical Applications. Urologia 2005. [DOI: 10.1177/039156030507200303] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Tissue engineering follows the principles of cell and tissue culture, cloning and stem cell production, and materials science to develop biological substitutes, which could repair and maintain normal function. The biomaterials must be able to control the structure and function of engineered tissue by interacting with both transplanted and host cells. Either natural or synthetic biodegradable materials have been used as cell delivery scaffolds. The stem cell field is also advancing rapidly, opening new options for regenerative medicine. In the genitourinary system, tissue engineering has been applied experimentally for the reconstitution of pelvis, ureter, bladder, urethra, penile corpora cavernosa and testis. This literature review underlines recent advances that have occurred in tissue engineering and describes their clinical repercussions, particularly in offering novel therapies in urogenital pathology.
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Affiliation(s)
- C. Alberti
- Struttura Complessa di Urologia, Azienda Ospedaliera “Santa Croce e Carle”, Cuneo
| | - M. Mediago
- Struttura Complessa di Urologia, Azienda Ospedaliera “Santa Croce e Carle”, Cuneo
| | - G. Chiapello
- Struttura Complessa di Urologia, Azienda Ospedaliera “Santa Croce e Carle”, Cuneo
| | - G Arena
- Struttura Complessa di Urologia, Azienda Ospedaliera “Santa Croce e Carle”, Cuneo
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Abstract
There has been considerable focus on the ability of bone marrow-derived cells to differentiate into non-haematopoietic cells of various tissue lineages, including cells of the kidney. This growing evidence has led to a reconsideration of the source of cells contributing to renal repair following injury. The kidney has an inherent ability for recovery and regeneration following acute damage. It is thought that dedifferentiation of glomerular and tubular cells to a more embryonic/mesenchymal phenotype represent key processes for recovery in response to damage. However, there has been much contention as to the source of regenerating renal cells. The present review focuses on new aspects of the plasticity of intrinsic renal cells and their role in renal remodelling and scarring. Growing support also suggests that bone marrow-derived cells have the ability to contribute to structural and functional repair following acute renal failure. Evidence for bone marrow cell engraftment in the repairing kidney leading to incorporation into a variety of tissue types is discussed. Because cell death and fibrosis is a common end-point in a variety of acute and chronic renal nephropathies, the paradigm of stem cell plasticity may have important implications in the cellular and pathological mechanisms of renal injury and repair. A better understanding of the processes controlling extra-renal cell engraftment and intrinsic renal cell differentiation may provide important clues for the development of new cell-based therapies in the field of renal reparative medicine.
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Affiliation(s)
- Sharon D Ricardo
- Monash Immunology and Stem Cell Laboratories (MISCL) and Department of Anatomy and Cell Biology, Monash University, Melbourne, Victoria, Australia.
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de Diego Rodríguez E, Villanueva Peña A, Roca Edreira A, Martín García B, Meana Infiesta A, Gómez Llames S, Gómez Román J. [Experimental study about viability of autologous free graft in vitro cultivated urinary epithelium]. Actas Urol Esp 2005; 28:714-31. [PMID: 15666514 DOI: 10.1016/s0210-4806(04)73173-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
OBJECTIVE The purpose of this study is to apply the in vitro keratinocyte culture techniques and the tissue engineering principles to urothelium, to obtain a three-dimensional autologous tissue suitable for grafting. We also showed the viability of free graft cultured urothelium in an experimental model. MATERIAL AND METHODS An animal experimental model was designed to apply the techniques of cellular culture and tissue engineering. Biopsy specimens of bladder mucosa were obtained, in vitro cultured and posteriorly implanted in each animal. We established three groups based on different follow-up periods (7, 14 and 30 days), and made a final histomorphological study to demonstrate the viability of the graft at the end of its respective follow-up period. RESULTS A three-dimensional in vitro tissue was obtained, composed of a bio-artificial submucosa (fibrin gel and fibroblast) where the uroepithelial cells were seeding; a biodegradable polyglycolic acid mesh was used to facilitate the tissue manipulation and implantation. In the morphological study all the implants appeared viable, but the grafts with longer implantations periods were better conformed, showing a tisular structure with multiple cellular layers. CONCLUSIONS In vitro keratinocyte culture techniques could be applied to other epithelial tissues as the urothelium. We obtained a three-dimensional in vitro tissue suitable for grafting in a relatively short time. The histological study demonstrated that free autologous urothelial graft is totally viable, opening future clinics applications.
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Schultheiss D, Gabouev AI, Kaufmann PM, Schlote N, Mertsching H, Haverich A, Stief CG, Jonas U. Biologische vaskularisierte Matrix (BioVaM). Urologe A 2004; 43:1223-8. [PMID: 15549160 DOI: 10.1007/s00120-004-0702-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
A new technique is presented to harvest an acellular matrix from a porcine small bowel segment preserving the mesenteric arterial and venous pedicles. Reseeding of this biological vascularized matrix (BioVaM) with functional cells, i.e. smooth muscle and urothelial cells isolated from the urinary tract, and resurfacing of its vascular structures with endothelial precursor cells results in a vascularized tissue engineered graft for reconstruction and augmentation of the urinary bladder. First promising short term implantation experiments using a porcine model for the evaluation of early graft perfusion after vascular anastomosis are presented.
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Affiliation(s)
- D Schultheiss
- Klinik und Poliklinik für Urologie und Kinderurologie, Medizinische Hochschule Hannover.
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Mason C, Markusen JF, Town MA, Dunnill P, Wang RK. The potential of optical coherence tomography in the engineering of living tissue. Phys Med Biol 2004; 49:1097-115. [PMID: 15128192 DOI: 10.1088/0031-9155/49/7/002] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The better repair of human tissue is an urgent medical goal and in order to achieve a safe outcome there is a parallel need for sensitive, non-invasive methods of assessing the quality of the engineered tissues and organs prior to surgical implantation. Optical coherence tomography (OCT) can potentially fulfil this role. The current status of OCT as an advanced imaging tool in clinical medicine, developmental biology and material science is reviewed and the parallels to the engineering of living tissue and organs are discussed. Preliminary data are also presented for a tissue engineering bioreactor with in situ OCT imaging. The data suggest that OCT can be utilized as a real time, non-destructive, non-invasive tool to critically monitor the morphology of tissue-engineered constructs during their fabrication and growth.
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Affiliation(s)
- C Mason
- Department of Biochemical Engineering, University College London, London WC1E 7JE, UK.
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Al-Singary W, Arya M, Patel HRH. Bladder neck stenosis after transurethral resection of prostate: does size matter? Urol Int 2004; 73:262-265. [PMID: 15539848 DOI: 10.1159/000080839] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2003] [Accepted: 03/17/2004] [Indexed: 11/19/2022]
Abstract
AIM To understand the risk factors associated with the incidence of bladder neck stenosis (BNS) after transurethral prostate surgery. PATIENTS AND METHODS We retrospectively reviewed 900 patients who underwent transurethral prostate surgery over a 4-year period. The mean age of the men was 72.3 (47-94) years. The specific outcome data assessed related to BNS, including type of operation performed, resected tissue weight and history of previous surgery in the lower urinary tract. RESULTS 29 (3.4%) patients developed BNS at a mean of 10.3 (3-33) months, with a mean resected prostatic tissue weight of 11+/-3.7 g. Four of the 29 patients with BNS were treated with bladder neck resection and re-stenosed. Fifty-four men underwent bladder neck incision for small prostates with a high bladder neck, measured by digital rectal examination and assessed cystoscopically, with no BNS. All the remaining patients from our series did not have a BNS, with a mean resected weight of 28+/-8.9 g, which is statistically greater than in the BNS group (p<0.05, unpaired t test). CONCLUSIONS BNS after transurethral prostate surgery is a significant problem. It is clear from our study that resection in small prostates with no sign of a high bladder neck will increase the development of BNS. Thus, small prostates should be managed by an initial bladder neck incision, even if the bladder neck is not high.
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Affiliation(s)
- W Al-Singary
- Department of Urology, Worthing Hospital NHS Trust, Worthing, UK
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