|  |  |  | | | | | TERMSC | | | | | | | | | | | | | | | | | | | Enhancement of bone formation by BMP-7 transduced MSCs on biomimetic nano-hydroxyapatite/polyamide composite scaffolds in repair of mandibular defects. J Biomed Mater Res A. 2010 Sep 15; Authors: Li J, Li Y, Ma S, Gao Y, Zuo Y, Hu J This study was to evaluate enhanced bone formation by bone morphogenetic protein-7 (BMP-7) transduced MSCs on nano-hydroxyapatite/polyamide (n-HA/PA) composite scaffolds for bone tissue engineering in repair of mandibular defect. n-HA/PA scaffolds were prepared and rabbit MSCs were separated and expanded; and then infected with adenoviral-mediated BMP-7 in vitro. The MSCs-BMP-7 and MSCs were seeded on the porous scaffolds. Scaffold/MSCs-BMP-7 constructs and scaffold/MSCs constructs were implanted in the defects of rabbits' mandible as the experimental groups A (n = 18) and groups B (n = 18), respectively, the pure scaffolds were implanted as controls (group C, n = 18). Six animals were sacrificed at 4-, 8-, and 16-week postimplantation, respectively. Their mandibles were removed and processed for radiographic, biomechanical tests, histological, and histomorphometric analysis. Group A animals showed greater bone formation and earlier mineralization than group B at 4- and 8-week postimplantation and similarly group B more than group C. However, no difference was found among three groups at 16-week postimplantation. The results of this study suggest that BMP-7 transduced MSCs-n-HA/PA composite could significantly accelerate bone formation in the implant at early stage. BMP-7 mediated ex vivo gene transfer based on MSCs as seed cells, combined with porous n-HA/PA as scaffolds for bone tissue engineering might be an alternative or supplemental approach to repair the mandibular defects. © 2010 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2010. PMID: 20845497 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Effect of three-dimensional expansion and cell seeding density on the cartilage-forming capacity of human articular chondrocytes in type II collagen sponges. J Biomed Mater Res A. 2010 Sep 15; Authors: Francioli SE, Candrian C, Martin K, Heberer M, Martin I, Barbero A Chondrocytes for tissue engineering strategies are typically expanded in monolayer (2D), leading to cell dedifferentiation but allowing to generate large cell numbers for seeding into scaffolds. Direct chondrocyte culture in scaffolds, instead, may support better maintenance of the differentiated phenotype but reduce the extent of proliferation and thus the resulting cell density. This study investigates whether the quality of cartilaginous tissues generated in vitro by human articular chondrocytes (HAC) on type II collagen sponges is enhanced (1) by direct expansion on the scaffolds (3D), as compared with standard 2D, or (2) by increasing cell seeding density, which in turn requires extensive 2D expansion. Three-dimensional expansion of HAC on the scaffolds, as compared with 2D expansion for the same number of doublings, better maintained the chondrocytic phenotype of the expanded cells (13.7-fold higher levels of type II collagen mRNA) but did not enhance their accumulation of glycosaminoglycan (GAG) following chondrogenic culture. Instead, increasing the HAC seeding density in the scaffolds (from 25 × 10(3) to 66 × 10(3) cells/mm(3)) significantly improved chondrogenesis (up to 3.3-fold higher GAG accumulation and up to 9.3-fold higher type II collagen mRNA), even if seeded cells had to be expanded and dedifferentiated more extensively in 2D to reach the required cell numbers. This study indicates that, under the specific conditions tested, a high-seeding density of HAC in 3D scaffolds is more critical for the generation of cartilaginous constructs than the stage of cell differentiation reached following expansion. © 2010 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2010. PMID: 20845491 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Photochemical crosslinking of soluble wool keratins produces a mechanically stable biomaterial that supports cell adhesion and proliferation. J Biomed Mater Res A. 2010 Sep 15; Authors: Sando L, Kim M, Colgrave ML, Ramshaw JA, Werkmeister JA, Elvin CM Keratins extracted from various "hard tissues" such as wool, hair, and nails are increasingly being investigated as a source of abundant, biocompatible materials. In this study we explored a recent photochemical method to crosslink solubilized wool keratoses, with the aim of producing a mechanically favorable biomaterial. Wool proteins were isolated by oxidizing the disulfides and extracting the resulting soluble keratoses. The α- and γ-keratose fractions were analyzed by liquid chromatography-mass spectrometry to identify their constituent proteins. Hydrogels were produced by covalent crosslinking of the α-keratoses via a photo-oxidative process catalyzed by blue light, a ruthenium complex, and persulfate. The presence of dityrosine crosslinks was demonstrated by high performance liquid chromatography and mass spectrometry analyses. The crosslinked α-keratose material had moderate tensile strength and elasticity, and high adhesive strength. The material displayed modest shrinking after crosslinking, however the shrinking could be prevented by crosslinking in the presence of 2.5% glycerol, resulting in gels that did not shrink or swell. Small solutes such as Tris and glycerol influenced the crosslink density and elastic modulus of the crosslinked material. The α-keratose was able to support adhesion and growth of NIH/3T3 fibroblasts in vitro. The fabrication of mechanically stable keratin biomaterials by this facile photo-crosslinking method may be useful for various tissue engineering applications. © 2010 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2010. PMID: 20845488 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Utility of NucleoCounter for the chondrocyte count in the collagenase digest of human native cartilage. Cytotechnology. 2010 Sep 16; Authors: Yonenaga K, Nishizawa S, Akizawa M, Asawa Y, Fujihara Y, Takato T, Hoshi K In cartilage tissue engineering, viable cell numbers should be correctly counted in the collagenase digest of the biopsied cartilage. However, this is a difficult task due to the presence of matrix debris, cell ghosts and their aggregates. To search for the correct cell counting method in this situation, we evaluated the utility of an automatic cell counting device, the NucleoCounter, and compared it with conventional staining using the LIVE/DEAD® kit. We first measured the cell numbers of a standard chondrocyte sample by the NucleoCounter, which showed a high accuracy (R(2) = 0.9999) and reproducibility (%CV: 2.00-8.66). We then calculated the cell numbers and viability in some collagenase digests of native cartilage using either the NucleoCounter or LIVE/DEAD® kit, revealing that the total cell numbers, viable ones and viability were highly correlated between them (R(2) = 0.9601, 0.9638 and 0.917, respectively). However, both the intrapersonal and interpersonal variabilities in the NucleoCounter was significantly decreased to about 1/20-1/5, compared to that of the LIVE/DEAD® kit. The NucleoCounter was regarded as a useful tool for simple, rapid, and highly reproducible cell counts, which may not only provide constant experimental data in a certain laboratory, but also contribute to the high reproducibility of the clinical results of cartilage tissue engineering among multiple institutions. PMID: 20845070 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Malalignment and cartilage lesions in the patellofemoral joint treated with autologous chondrocyte implantation. Knee Surg Sports Traumatol Arthrosc. 2010 Sep 16; Authors: Vasiliadis HS, Lindahl A, Georgoulis AD, Peterson L PURPOSE: The aim of our current study is to present the 12.6 years' follow-up results in patients with cartilage lesions of the patellofemoral joint, treated with autologous chondrocyte implantation (ACI) with the use of periosteum. METHODS: Ninety-two patients having patella or trochlea lesion participated in this study. Lysholm and Tegner questionnaires were completed 12.6 years (SD 2.3 years) after the surgery. The patients were asked whether they feel better, worse or had not experienced any difference compared to previous years and whether they would undergo the operation again. Complications or subsequent surgeries were also assessed. RESULTS: Median Tegner score was three, improved by one level compared with preoperative values (P = 0.02). Median Lysholm score was 70, improved by nine points (n.s.). Seventy-two percent of the patients were better or unchanged while 93% would undergo the operation again. Patients with no kissing lesions appeared to have a better prognosis. Patients with malalignment or instability that had undergone a realignment procedure had comparable outcomes to the patients that did not need any additional surgery. Realignment procedures increased the incidence of serious complications but they were associated with decreased incidence of periosteal hypertrophy. No association was found between the age of the patients at the time of the ACI or the size per lesion and any of the clinical outcomes. CONCLUSION: ACI provides a satisfactory outcome for the treatment of cartilage lesions of the patellofemoral joint, even for the cases with concomitant patellar instability. It seems that correcting the coexisting background factors with realignment, stabilizing or unloading procedures, along with the treatment of cartilage lesions, is improving the clinical outcomes over time and decreases the incidence of periosteal hypertrophies although increasing the incidence of serious complications. Our study reveals the good results and the high level of patients' activities (as shown by Tegner score), were preserved 12.6 years after the implantation, in both isolated trochlea and patella lesions and also in multiple and in kissing lesions where an intervention could be considered as a salvage procedure. PMID: 20845030 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Fabrication and mechanical characterization of 3D electrospun scaffolds for tissue engineering. Biomed Mater. 2010 Sep 15;5(5):055006 Authors: Wright LD, Young RT, Andric T, Freeman JW Electrospinning is a polymer processing technique that produces fibrous structures comparable to the extracellular matrix of many tissues. Electrospinning, however, has been severely limited in its tissue engineering capabilities because this technique has produced few three-dimensional structures. Sintering of electrospun materials provides a method to fabricate unique architectures and allow much larger structures to be made. Electrospun mats were sintered into strips and cylinders, and their tensile and compressive mechanical properties were measured. In addition, electrospun materials with salt pores (salt embedded within the material and then leached out) were fabricated to improve porosity of the electrospun materials for tissue engineering scaffolds. Sintered electrospun poly(d,l-lactide) and poly(l-lactide) (PDLA/PLLA) materials have higher tensile mechanical properties (modulus: 72.3 MPa, yield: 960 kPa) compared to unsintered PLLA (modulus: 40.36 MPa, yield: 675.5 kPa). Electrospun PDLA/PLLA cylinders with and without salt-leached pores had compressive moduli of 6.69 and 26.86 MPa, respectively, and compressive yields of 1.36 and 0.56 MPa, respectively. Sintering of electrospun materials is a novel technique that improves electrospinning application in tissue engineering by increasing the size and types of electrospun structures that can be fabricated. PMID: 20844321 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | GIP: No Longer the Neglected Incretin Twin? Sci Transl Med. 2010 Sep 15;2(49):49ps47 Authors: Kulkarni RN In the design of therapeutics to treat type 2 diabetes, researchers have exploited the observation that oral ingestion of nutrients leads to the secretion of glucose homeostasis-regulating incretin hormones (for example, glucagon-like-peptide-1) from the gut. Here, we discuss two recent papers that suggest that the "other" incretin hormone, gastric inhibitory polypeptide (GIP), also is important in the regulation of glucose homeostasis. These findings warrant further studies to unravel the mechanism of action of GIP in β-cells of the endocrine pancreas and to evaluate the possibility of designing novel therapeutics that target both incretin hormones. PMID: 20844284 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Regulatory Mechanisms that Mediate Tenascin C-Dependent Inhibition of Oligodendrocyte Precursor Differentiation. J Neurosci. 2010 Sep 15;30(37):12310-12322 Authors: Czopka T, von Holst A, Ffrench-Constant C, Faissner A Here, we present mechanisms for the inhibition of oligodendendrocyte precursor cell (OPC) differentiation, a biological function of neural extracellular matrix (ECM). The differentiation of oligodendrocytes is orchestrated by a complex set of stimuli. In the present study, we investigated the signaling pathway elicited by the ECM glycoprotein tenascin C (Tnc). Tnc substrates inhibit myelin basic protein (MBP) expression of cultured rat oligodendrocytes, and, conversely, we found that the emergence of MBP expression is accelerated in forebrains of Tnc-deficient mice. Mechanistically, Tnc interfered with phosphorylation of Akt, which in turn reduced MBP expression. At the cell surface, Tnc associates with lipid rafts in oligodendrocyte membranes, together with the cell adhesion molecule contactin (Cntn1) and the Src family kinase (SFK) Fyn. Depletion of Cntn1 in OPCs by small interfering RNAs (siRNAs) abolished the Tnc-dependent inhibition of oligodendrocyte differentiation, while Tnc exposure impeded the activation of the tyrosine kinase Fyn by Cntn1. Concomitant with oligodendrocyte differentiation, Tnc antagonized the expression of the signaling adaptor and RNA-binding molecule Sam68. siRNA-mediated knockdown or overexpression of Sam68 delayed or accelerated oligodendrocyte differentiation, respectively. Inhibition of oligodendrocyte differentiation with the SFK inhibitor PP2 could be rescued by Sam68 overexpression, which may indicate a regulatory role for Sam68 downstream of Fyn. Our study therefore uncovers the first signaling pathways that underlie Tnc-induced, ECM-dependent maintenance of the immature state of OPCs. PMID: 20844127 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Interactions between Hedgehog proteins and their binding partners come into view. Genes Dev. 2010 Sep 15;24(18):2001-2012 Authors: Beachy PA, Hymowitz SG, Lazarus RA, Leahy DJ, Siebold C Hedgehog (Hh) proteins are secreted signaling molecules that mediate essential tissue-patterning events during embryonic development and function in tissue homeostasis and regeneration throughout life. Hh signaling is regulated by multiple mechanisms, including covalent lipid modification of the Hh protein and interactions with multiple protein and glycan partners. Unraveling the nature and effects of these interactions has proven challenging, but recent structural and biophysical studies of Hh proteins and active fragments of heparin, Ihog, Cdo, Boc, Hedgehog-interacting protein (Hhip), Patched (Ptc), and the monoclonal antibody 5E1 have added a new level of molecular detail to our understanding of how Hh signal response and distribution are regulated within tissues. We review these results and discuss their implications for understanding Hh signaling in normal and disease states. PMID: 20844013 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Regenerative medicine: the emergence of an industry. J R Soc Interface. 2010 Sep 15; Authors: Nerem RM Over the last quarter of a century there has been an emergence of a tissue engineering industry, one that has now evolved into the broader area of regenerative medicine. There have been 'ups and downs' in this industry; however, it now appears to be on a track that may be described as 'back to the future'. The latest data indicate that for 2007 the private sector activity in the world for this industry is approaching $2.5 billion, with 167 companies/business units and more than 6000 employee full time equivalents. Although small compared with the medical device and also the pharmaceutical industries, these numbers are not insignificant. Thus, there is the indication that this industry, and the related technology, may still achieve its potential and address the needs of millions of patients worldwide, in particular those with needs that currently are unmet. PMID: 20843840 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Proliferation of Chondrocytes on a 3-D Modelled Macroporous Poly(Hydroxyethyl Methacrylate)-Gelatin Cryogel. J Biomater Sci Polym Ed. 2010 Sep 14; Authors: Singh D, Tripathi A, Nayak V, Kumar A Tissue-engineering constructs should be designed to mimic the native tissue environment for cells, the scaffold matching to stiffness and strength of the tissues while maintaining an interconnected porous network and a reasonable porosity. This study presents a new single-step protocol for synthesis of a poly(hydroxyethyl methacrylate)-poly(ethylene glycol) diacrylate-gelatin (HPG) macroporous polymeric scaffold with well-controlled porous structure and good mechanical strength. The pore size of these matrices lies in the range of 30 to 100 μm with an average pore diameter of 80 μm and with an interconnected pore structure as analyzed by scanning electron microscopy. Further, interconnectivity was also confirmed by high solvent uptake capacity, as the cryogel reached its equilibrium within 2 min. The gels also showed substantial mechanical integrity, i.e., the average compressive modulus was 32.73±2.36 kPa at 15% compression of their original length. The degree of weight loss of these cryogels was found to be approx. 88% within 8 weeks of incubation in PBS (pH 7.4) at 37°C. Physio-chemically optimized cryogel was further evaluated for in vitro growth and proliferation of isolated primary goat chondrocytes up to 3 weeks. The cell adherence on cryogel was examined by SEM analysis, while cell-matrix interaction was examined by 4'-6-diamidino-2-phenylindole and propidium iodide staining. Furthermore, the cell compatibility and proliferation was evaluated using the MTT assay. Increase in total cellular metabolic activity was observed as shown by continuous increase in glycosaminoglycan and collagen contents with time. Collagen type-I and type-II gene expression analysed for over 3 weeks by RT-PCR showed the prominent expression of collagen type-II. These results suggest the use of synthesised cryogel scaffold as a matrix for chondrocyte attachment and proliferation in 3-D environment and as a delivery system in cartilage-tissue engineering. PMID: 20843432 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | [Current situation and prospect of treatment for radiation-induced lung injury] Sheng Wu Yi Xue Gong Cheng Xue Za Zhi. 2010 Aug;27(4):937-40 Authors: Li X, Xue J, Lu Y Radiation-induced lung injury (RILI) is the most common complication of the radiotherapy for thoracic tumor. It can lower the ratio of local control and seriously affect the patients' quality of life. At present, the clinical management of RILI is not more than the use of glucocorticoid and anti-inflammatory agent for symptomatic treatments. These treatments do not have any preventive effect but cause much side reactions. In this paper, we review the data from the contigency researches on the mechanism of RILI, from the researches on gene therapy and stem cell-therapy, and we dicuss the more safe, more stable and more efficacious treatment of RILI. PMID: 20842876 [PubMed - in process] | | | | | | | | | | | | | | | | | | | | | | | | | [Experimental research on osteogenic abilities of new bone tissue engineering scaffolds by recombinant bone morphogenetic protein] Sheng Wu Yi Xue Gong Cheng Xue Za Zhi. 2010 Aug;27(4):825-8 Authors: Li Y, Ran W, Liu M, Liu Y This research sought to asses the efficacity of a new type of tissue engineering bone developed by PDLLA/ PLA-PEG-PLA and BMP as a kind of bone graft substitute in the rabbit model of mandibular defects; 15 mm x 6 mm bilateral mandibular periosteum bone defects were made surgically in 20 New Zealand adult rabbits. The porous scaffolds impregnated with rhBMP-2 were used for the purpose, and the scaffolds without rhBMP-2 were used as control. The methods adopted in this research were: macroscopy, histomorphologic exam, X-ray exam, SEM micrography, computer-aided analysis and graphics. The experimental group was shown to have an earlier inception of bone forming. New bone formation was seen along the border of the original mandibular bone and in the middle. At 12 weeks after surgery,the defects were almost filled with new bone. In the control group, the defects could not be repaired in its entirety, and there was no new bone in the middle. The porous scaffold is a promising carrier for BMP. This kind of bone graft substitute can serve as an osteoconductive and osteoinductive matrix. PMID: 20842853 [PubMed - in process] | | | | | | | | | | | | | | | | | | | | | | | | | [The preparation of collagen sponge as tissue engineering scaffolds and analysis of its pore structure] Sheng Wu Yi Xue Gong Cheng Xue Za Zhi. 2010 Aug;27(4):820-4 Authors: Qin S, Chen H, Yang X, Ye C, Kang N, Tan J, Dai L The preparation of collagen sponges was studied in order to develop tissue engineering scaffolds. Collagen solutions with varying concentrations were obtained by condensing the initial collagen with polyethylene glycol (PEG) at 4 degrees C for different periods of time, and then were freeze-dried to make collagen scaffolds. The porous characteristics of the prepared scaffolds were characterized by use of different methods, including laser scanning confocal microscopy (LSCM), scanning electron microscopy (SEM) and tensile tests. All collagen sponges were shown to have similar interconnected porous structures but were found to have different pore size, porosity, water capacity and the mechanical property, depending on the concentration of collagen solutions. These findings indicate that the way of controlling the concentration of collagen solutions with PEG permits the freeze-drying fabrication of collagen sponges with varying porous features suitable for different tissue engineering purposes. PMID: 20842852 [PubMed - in process] | | | | | | | | | | | | | | | | | | | | | | | | | [The surface modification of eguus asinus augment fibroblast adhesion and proliferation on silk fibroin materials] Sheng Wu Yi Xue Gong Cheng Xue Za Zhi. 2010 Aug;27(4):806-10 Authors: Lian X, Wang S, Zhu H, Gao Z Eguus asinus is one of the rare Chinese drugs famous for promoting blood circulation. In this experiment, it was employed to modify the silk fibroin (SF) by physical blending. Mouse embryonic fibroblasts NIH-3T3 were seeded on pure and modified SF surfaces. The morphological changes of cell on SF surfaces were characterized by optical microscope images. The cell adhesion diameter, the attachment force (F) of a single cell and cell proliferation on SF surfaces were measured by micropipette aspiration system and MTT assay. The results indicated that the fibroblasts seeded on modified SF had larger cell adhesion area, stronger initial attachment force and higher cell proliferation than did the pure SF. In conclusion, eguus asinus improved the adhesion and proliferation of fibroblasts on SF. The research promoted the further use of Chinese drug eguus asinus in tissue engineering. PMID: 20842849 [PubMed - in process] | | | | | | | | | | | | | | | | | | | | | | | | | [Electrical stimulation enhances viability of osteoblasts on conductive biodegradable material] Sheng Wu Yi Xue Gong Cheng Xue Za Zhi. 2010 Aug;27(4):801-5 Authors: Men J, Deng X, Xu Z This study was aimed at exploring the viability of osteoblasts on conductive tissue engineering material. Conductive biodegradable Polyprrole/Polylactide (PPy/PLA) was prepared by emulsion polymerization. Scanning electron microscope (SEM) and spectroscopy showed evenly dispersed PPy in PLA. PPy/PLA membrane was found being able to keep conductive stability for more than one month to provide electric circumstances (ECs) for osteoblasts. SEM displayed that osteoblasts adhered and spread well on PPy/PLA. ECs of 12.5, 25, 50, 75, 100, 125, 150, 175, 200 microA/cm2 were separately used to stimulate osteoblasts for 24h, 48h, 72h and 96h. Methyl-thiazole-tetrazolium (MTT) assay after 24h revealed that 50 microA/cm2 evidently accelerated osteoblasts proliferation. Alkaline phosphatase (ALP) activity assay revealed that, 48h later, 50 microA/cm2, and 75 microA/cm2 promoted osteoblasts differentiation. 50 microA/cm2 enhanced osteoblasts mineration. Conclusively, 50 microA/cm2 can strengthen osteoblasts' function and promote their viability. PMID: 20842848 [PubMed - in process] | | | | | | | | | | | | | | | | | | | | | | | | | Long-term evaluation of elongating columella using conchal composite graft in bilateral secondary cleft lip and nose deformity. Plast Reconstr Surg. 2010 Aug;126(2):543-53 Authors: Cheon YW, Park BY BACKGROUND: A short columella is one of the most severe problems in bilateral cleft lip and nose deformity. In particular, with tissue insufficiency or scar contracture on the upper lip, it is very hard to achieve a good nasal profile with conventional methods. METHODS: One hundred thirty-seven patients with a short columella were operated on from February of 1987 to December of 2008. The average age at operation was 7.3 years. The conchal cartilage was harvested. The preauricular or postauricular skin-subcutaneous fat composite tissue was harvested. Through a transcolumellar incision, the conchal cartilage was inset and the defect was covered with skin-fat composite tissue. The serial nasal profiles were evaluated before and after surgery. Also, the postoperative nasal profiles were compared with normal profiles. The postoperative color difference with surrounding skin was measured by the L*a*b* photographic analysis method. RESULTS: The mean height and width of skin-subcutaneous fat composite tissue were 9.81 and 22.14 mm, respectively. The preoperative and postoperative measuring for columella height was 5.1 + or - 1.1 mm and 14.2 + or - 1.5 mm. The columella-lip angle was 120.30 + or - 12.97 preoperatively degrees and 98.76 + or - 10.98 degrees postoperatively, whereas the angle of columellar-alar triangle was 111.56 + or - 11.39 degrees and 97.91 + or - 11.49 degrees, respectively. None of the postoperative profiles were different from those of normal Korean people of the same age except in the 0- to 6-year-old group (p < 0.05). The color match was best with preauricular composite tissue. Complications included total necrosis in three cases and partial necrosis in 12 cases that were treated conservatively. CONCLUSION: Elongating columella using a composite graft can be a satisfying alternative, especially for a severe short columella with upper lip tissue deficiency. PMID: 20679836 [PubMed - indexed for MEDLINE] | | | | | | | | | | | | | | | | | | | | | | | | | 2010 Nicolas Andry Award: Multipotent adult stem cells from adipose tissue for musculoskeletal tissue engineering. Clin Orthop Relat Res. 2010 Sep;468(9):2530-40 Authors: Guilak F, Estes BT, Diekman BO, Moutos FT, Gimble JM BACKGROUND: Cell-based therapies such as tissue engineering provide promising therapeutic possibilities to enhance the repair or regeneration of damaged or diseased tissues but are dependent on the availability and controlled manipulation of appropriate cell sources. QUESTIONS/PURPOSES: The goal of this study was to test the hypothesis that adult subcutaneous fat contains stem cells with multilineage potential and to determine the influence of specific soluble mediators and biomaterial scaffolds on their differentiation into musculoskeletal phenotypes. METHODS: We reviewed recent studies showing the stem-like characteristics and multipotency of adipose-derived stem cells (ASCs), and their potential application in cell-based therapies in orthopaedics. RESULTS: Under controlled conditions, ASCs show phenotypic characteristics of various cell types, including chondrocytes, osteoblasts, adipocytes, neuronal cells, or muscle cells. In particular, the chondrogenic differentiation of ASCs can be induced by low oxygen tension, growth factors such as bone morphogenetic protein-6 (BMP-6), or biomaterial scaffolds consisting of native tissue matrices derived from cartilage. Finally, focus is given to the development of a functional biomaterial scaffold that can provide ASC-based constructs with mechanical properties similar to native cartilage. CONCLUSIONS: Adipose tissue contains an abundant source of multipotent progenitor cells. These cells show cell surface marker profiles and differentiation characteristics that are similar to but distinct from other adult stem cells, such as bone marrow mesenchymal stem cells (MSCs). CLINICAL RELEVANCE: The availability of an easily accessible and reproducible cell source may greatly facilitate the development of new cell-based therapies for regenerative medicine applications in the musculoskeletal system. PMID: 20625952 [PubMed - indexed for MEDLINE] | | | | | | | | | | | | | | | | | | | | | | | | | Impaired myocardium regeneration with skeletal cell sheets--a preclinical trial for tissue-engineered regeneration therapy. Transplantation. 2010 Aug 27;90(4):364-72 Authors: Miyagawa S, Saito A, Sakaguchi T, Yoshikawa Y, Yamauchi T, Imanishi Y, Kawaguchi N, Teramoto N, Matsuura N, Iida H, Shimizu T, Okano T, Sawa Y BACKGROUND: We hypothesized that autologous skeletal cell (SC) sheets regenerate the infract myocardium in porcine heart as a preclinical trial. METHODS AND RESULTS: The impaired heart was created by implantation of ameroid constrictor on left anterior descending for 4 weeks. SCs isolated from leg muscle were cultured and detached from the temperature-responsive domain-coated dishes as single monolayer cell sheet at 20 degrees C. The following therapies were conducted: SC sheets (SC group, n=5); sham (C group n=5). Echocardiography demonstrated that cardiac performance was significantly improved in the SC group 3 and 6 months after operation (fractional area shortening, 3 months; SC vs. C=49.5+/-2.8 vs. 24.6+/-2.0%, P<0.05) and left ventricle dilatation was well attenuated in the SC group. Color kinesis index showed that distressed regional diastolic and systolic function in infarcted anterior wall was significantly recovered (SC vs. C=57.4+/-8.6 vs. 30.2+/-4.7%, P<0.05, diastolic: 58.5+/-4.5 vs. 35.4+/-6.6%, P<0.05, systolic). Factor VIII immunostains demonstrated that vascular density was significantly higher in the SC group than the C group. And % fibrosis and cell diameter were significantly lower in the SC group. And hematoxylin-eosin staining depicted that skeletal origin cells and well-developed-layered smooth muscle cells were detected in the implanted area. Positron emission tomography showed better myocardial perfusion and more viable myocardial tissue in the distressed myocardium receiving SC sheets compared with the myocardium receiving no sheets. CONCLUSIONS: SC sheet implantation improved cardiac function by attenuating the cardiac remodeling in the porcine ischemic myocardium, suggesting a promising strategy for myocardial regeneration therapy in the impaired myocardium. PMID: 20555308 [PubMed - indexed for MEDLINE] | | | | | | | | | |  | |  | |  |
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