Comparison of intensity-modulated radiation therapy alone vs. intensity-modulated radiation therapy combined with chemotherapy in elderly nasopharyngeal carcinoma patients (aged >65 years).

PURPOSE: The efficacy and tolerability of adding chemotherapy to radiotherapy in the era of intensity-modulated radiation therapy (IMRT) remain controversial among older patients with nasopharyngeal carcinoma (NPC). The present study compared IMRT alone with IMRT in combination with chemotherapy in elderly NPC patients. METHODS: Between January 2011 and December 2014, 102 patients aged >65 years with NPC who received IMRT alone (IMRT group) or IMRT in combination with chemotherapy (IMRT/CT group) were enrolled. Patients from both treatment arms were pair-matched (1:1 ratio) based on six clinical factors. Differences in overall survival (OS), disease-free survival (DFS), locoregional relapse-free survival (LRRFS), and distant metastasis-free survival (DMFS) were assessed using the Kaplan-Meier method and Cox proportional hazards models, whereas the toxicity profile was assessed using Common Terminology Criteria for Adverse Events (CTCAE) version 4. RESULTS: No significant differences were noted in OS (72.1% vs. 72.5%, p = 0.799), DFS (65.9% vs. 70.1%, p = 0.733), LRRFS (76.4% vs. 71.6%, p = 0.184), and DMFS (90.8% vs. 98.0%, p = 0.610) between the IMRT and IMRT/CT groups. Multivariate analyses showed that chemotherapy was not an independent factor for OS, DFS, LRRFS, and DMFS. However, the incidences of grade 3 vomiting/nausea (p = 0.000), leukopenia/neutropenia (p = 0.000), thrombocytopenia (p = 0.041), and anemia (p = 0.040) were significantly higher in the IMRT/CT group compared with the IMRT group. No grade 4 toxicities were observed. CONCLUSION: IMRT alone was similar to IMRT/CT in treating elderly NPC patients (age >65 years), with comparable survival outcomes and less grade 3 toxicities.

Seasonal Variations in Microtia of Chinese Population.

BACKGROUND: Seasonality of congenital birth defect could help to identify environmental risk factors. Data concerning the seasonality of the prevalence of microtia are little. This article aims to determine whether births of microtia follow a certain pattern. METHODS: Data were obtained from 2669 patients with microtia who were admitted to Second Ear Reconstruction Center of Plastic Surgery Hospital, Chinese Academy of Medical Science from January 2007 to December 2013. The controls consist of all living births from the Obstetric Department of the Haidian Maternal & Child Health Hospital during the same time. Seasonal variations in months of births were analyzed by using χ test. RESULTS: A total of 2669 patients with microtia and 89,273 healthy living newborns were included in this study. Birth time peak of the patients occurred in autumn, especially in November, compared with the nadir in the spring, especially in April (P G 0.05). The birth time peak of male patients occurred in autumn, too, especially in October and November, While the valley occurred in spring (April, too). However, the seasonality in female patients is not so apparent with the peak occurred in the tail of summer and autumn, especially in August, November, and September orderly, while the valley occurred in March. CONCLUSIONS: There is a possible seasonality in birth months and a difference between sexes of patients with microtia in this native Chinese population. This approach could be useful to study the etiology of microtia.

One-Year Relapse of Mandibular Distraction for Hemifacial Microsomia Using Masseteric Botulinum Toxin Type A Injections.

BACKGROUND: The relapse of hemifacial microsomia was thought to be highly related to the soft tissue envelope around the mandible angle mainly composed by masseter and medial pterygoid. According to the reason, we tried to apply masseter injection of type A botulinum toxin to weaken the soft envelope tension on the early stage post mandible distraction in adult HFM patients. METHODS: Eight patients diagnosed with HFM were studied and randomly assigned to an experimental or control group. Patients in the experimental group were treated with DO, orthognathic surgeries, autologous fat grafting, and bilateral masseter muscle injection with type A botulinum toxin. The patients in control group were treated with the same procedures as the patients in experimental group except for masseter muscle injection with type A botulinum toxin. The recurrence rates of both groups were evaluated and analyzed after nearly 1 year of follow-up. RESULTS: The mean recurrence rate was 26.30% ±â€Š11.84% (range 7.62%-37.27%) in the 8 patients after 1-year follow-up. The relapse rate was 16.32% ±â€Š7.78% (7.62%-26.22%) in the experimental group and 36.28% ±â€Š1.03% (34.84%-37.27%) in the control group. There was a significant difference (P = 0.002) between the experimental group and the control group. CONCLUSIONS: The combination of DO, orthognathic surgeries, autologous fat particle transplantation, and masseter muscle type A botulinum toxin injection technique could be a comprehensive treatment plan for adult patients of HFM. Furthermore, masseter injection of type A botulinum toxin might be an alternative method to reduce the early recurrence rate of postoperative adult patients of HFM.

Evaluation of human platelet lysate and dimethyl sulfoxide as cryoprotectants for the cryopreservation of human adipose-derived stem cells.

Cryopreservation provides an effective technique to maintain the functional properties of human adipose-derived stem cells (ASCs). Dimethylsulfoxide (DMSO) and fetal bovine serum (FBS) are frequently used as cryoprotectants for this purpose. However, the use of DMSO can result in adverse effects and toxic reactions and FBS can introduce risks of viral, prion, zoonose contaminations and evoke immune responses after injection. It is therefore crucial to reduce DMSO concentrations and use serum-free solution in the cryopreservation process. Human platelet lysate (PL) is a promising candidate for use as an alternative to DMSO and FBS. Therefore, in this study, with an aim to identify a cryoprotective agent for ASC cryopreservation, we determined the viability, proliferation potential, phenotype, and differentiation potential of fresh ASCs and ASCs cryopreserved using different combinations of three cryoprotective agents: fetal bovine serum (FBS), dimethylsulfoxide (DMSO), and human platelet lysate (PL). The viability of the ASCs cryopreserved with 90% FBS and 10% DMSO, 95% FBS and 5% DMSO, and 97% PL and 3% DMSO was >80%, and the proliferation potentials, cell phenotypes, and differentiation potentials of these groups were similar to those of fresh ASCs. Together, our findings suggest that a combination of 97% PL and 3% DMSO is an ideal cryoprotective agent for the efficient cryopreservation of human ASCs.

Comparison of ultrasound biomicroscopy and spectral-domain anterior segment optical coherence tomography in evaluation of anterior segment after laser peripheral iridotomy.

AIM: To quantitatively assess narrow anterior chamber angle using spectral-domain anterior segment optical coherence tomography (SD-AS-OCT) and ultrasound biomicroscopy (UBM), and to evaluate the correlations and consistency between SD-AS-OCT and UBM. METHODS: Fifty-five eyes from 40 patients were examined. Patients were diagnosed with primary angle-closure glaucoma (PACG) remission (11 eyes from 8 patients), primary angle closure (PAC, 20 eyes from 20 patients) and PAC suspect (24 eyes from 12 patients). Each eye was examined by SD-AS-OCT and UBM after laser peripheral iridotomy (LPI). The measurements of SD-AS-OCT were angle open distance (AOD), anterior chamber angle (ACA), trabecular iris angle (TIA), and trabecular iris space area (TISA). UBM measurements were AOD and TIA. Correlations of AOD500 and TIA500 between UBM and AS-OCT were assessed. All parameters were analysed by SPSS 16.0 and MedCalc. RESULTS: ACA, TIA and AOD measured by SD-AS-OCT reached a maximum at the temporal quadrant and minimum at the nasal quadrant. TISA reached the maximum at the inferior and minimum at the superior quadrant. Group parameters of AOD500 and AOD750 showed a linear positive correlation, and AOD750 had less variability. UBM outcomes of AOD500 and TIA500 were significantly smaller than those of SD-AS-OCT. The results of the two techniques were correlated at the superior, nasal and inferior quadrants. CONCLUSION: Both UBM and SD-AS-OCT are efficient tools for follow-up during the course of PACG. We recommended using parameters at 750 µm anterior to the sclera spur for the screening and follow-up of PACG and PAC. The two methods might be alternatives to each other.

The Retrograde Transposition of the Remnant Earlobe in Patients With Low-Set Microtia.

During auricle reconstruction, lobular transposition has become a routine technique applied by most of surgeons. But to some low-set remnant ears, it is difficult to manipulate the conventional lobule transposition method in clinical application. In this article, the authors introduce a method to retrogradely transpose the remnant ear with the the ratio of length:width of the lobular flap being 4-5:1. The lobule transposition could be applied during the first stage of Nagata method or the third stage using expansion method. The authors take the superior part of the remnant ear as the pedicle and make the incision at the middle and inferior parts of the remnant ear to form the lobular flap. Then the inferior lobule is rotated posteriorly and superiorly to cover the rear end of the framework and to form the inferior part of helical rim. The results of the reconstructed auricles are satisfactory with aesthetic natural earlobes and the location of the reconstructed ear is symmetric to the contralateral ear. The authors believe that to the 2% to 5% patients with low-set microtia, this is a good way to make use of remnant ear for the purpose of a real earlobe.

TGF-ß1 induces the formation of vascular-like structures in embryoid bodies derived from human embryonic stem cells.

Human embryonic stem cells (ESCs) can differentiate into endothelial cells in response to stimuli from extracellular cytokines. Transforming growth factor (TGF)-ß1 signaling is involved in stem cell renewal and vascular development. Previously, human ESCs were isolated from inner cell mass and a stable ESC line was developed. In the present study, the effects of extracellular TGF-ß1 were investigated on human ESC-derived embryoid bodies (EB) in suspension. The structures of the EBs were analyzed with light and electron microscopy, while the cellular composition of the EBs was examined via the expression levels of specific markers. Vascular-like tubular structures and cardiomyocyte-like beating cells were observed in the EBs at day 3 and 8, respectively. The frequencies of vascular-like structures and beating cells in the TGF-ß1 treated group were significantly higher compared with the control group (84.31 vs. 12.77%; P<0.001; 37.25 vs. 8.51%; P<0.001, respectively). Electron microscopy revealed the presence of lumens and gap junctions in the sections of the tubular structures. Semiquantitative polymerase chain reaction revealed elevated expression levels of CD31 and fetal liver kinase-1 in EBs cultured with TGF-ß1. In addition, extensive staining of von Willebrand factor was observed in the vascular-like structures of TGF-ß1-treated EBs. Therefore, the results of the present study may aid the understanding of the underlying mechanisms of human ESC differentiation and improve the methods of propagating specific cell types for the clinical therapy of cardiovascular diseases.

[The application of comparative proteomic analysis to screen proteins associated with mechanical properties of engineered cartilage: a preliminary study].

OBJECTIVE: To study proteins correlated with the mechanical properties of engineered cartilage by screening significantly changed proteins during cartilage formation by comparative proteomic analysis. METHODS: Human chondrocyte, cultured and expanded, were seeded onto a polyglycolic acid/polylactic acid (PGA/PLA) scaffolds. After 4 weeks of culture in vitro, the constructs were divided into three groups. There were 6 specimens in each group. For the regular in vitro culture group (A), the constructs were kept in culture at the original condition for an additional 6 weeks. For in vivo groups, the constructs were implanted subcutaneously into nude mice for either 6 weeks (B) or 12 weeks (C). All specimens were harvested for gross observation, average wet weight and volume measurement, histology, immunohistochemistry and biomechanics to evaluate the results. Meanwhile, comparative proteomic analysis was performed for each group, and those proteins involved in extracellular matrix with at least 2 folds up-regulation were chosen for further exploration. The correlations between Young's modulus and the relative content of the selected proteins were analyzed by Pearson correlation coefficient. RESULTS: All these samples in the three groups eventually formed hyaline-like cartilage structure. Specimens in C and B groups were similar with adult articular cartilage in appearance, and had multiple mature lacuna in histology. However, those specimens in A group had loose texture with irregular hypertrophy lacuna. Specimens implanted for 12 weeks in vivo had better wet weight (372.5 +/- 35.4) mg and Young's modulus (8.68 +/- 2.65) MPa than those cultured in vivo for 6 weeks (346 +/- 34.5) mg, (3.25 +/- 1.24) MPa (P < 0.01). In group A, they were (184.4 +/- 12.28) mg and (0.7 +/- 0.23) MPa. This study had detected 44 proteins in ECM by comparative proteomic analysis, then chosing the greatest ratio of 6 up-regulation proteins compared between C and A groups. The correlation results indicated the content of Decorin, Chondroadherin and Fibromodulin were linear correlation with the mechanical properties of engineered cartilage (P < 0.05). CONCLUSIONS: Comparative proteomic analysis could provide large scale information of associated proteins, making it profit for advanced research on the relationship between extracellular matrix and mechanical properties of engineered cartilage by combination with tissue reconstruction techniques.

In vitro proliferation and differentiation of adipose-derived stem cells isolated using anti-CD105 magnetic beads.

The present study aimed to investigate the feasibility of isolating adipose-derived stem cells (ADSCs) by selecting cells that express the surface receptor CD105. Surface antigen expression of the unsorted cells was undertaken using FACS analysis. Primary adipose-derived cells were isolated. The second passage cells were incubated with anti-CD105 magnetic beads, and separated using a magnetic separator. Cell growth and colony formation was determined by counting and Giemsa staining, respectively. Cells also underwent histological immunohistochemical, and RT-PCR analyses to determine their chondrogenic, adipogenic and osteogenic potential. Increased cell proliferation and colony formation was observed in CD105-positive (CD105⁺) as compared to the CD105-negative (CD105⁻) cells (P<0.001). Following induction, the expression of type II collagen and the number of calcium deposits and lipid droplets in the CD105⁺ ADCs were markedly higher than in the CD105⁻ ADCs. Furthermore, increased alkaline phosphatase (AKP), leptin and PPARγ2 mRNA expression was detected in the CD105⁺ ADCs (P<0.01). Isolation of CD105⁺ ADSCs by MACS was feasible. Thus, CD105 can be used as a relatively specific marker for the selection of ADSCs. Although the chondrogenic, adipogenic and osteogenic potential of these cells is suggestive of their potential for use in tissue engineering treatments, further in vivo studies are necessary.

[Preliminary study of in vitro chondrogenesis by co-culture of chondrocytes and adipose-derived stromal cells].

OBJECTIVE: To explore the feasibility of in vitro chondrogenesis by co-culture of chondrocytes and adipose-derived stromal cells (ADSCs) so as to confirm the hypothesis that chondrocytes can provide chondrogenic microenvironment to induce chondrogenic differentiation of ADSCs. METHODS: Human ADSCs and porcine auricular chondrocytes were in vitro expanded respectively and then were mixed at the ratio of 7:3 (ADSCs: chondrocytes). 200 microl mixed cells (5.0 x 10(7)/ml) were seeded onto a polyglycolic acid/polylactic acid (PGA/PLA) scaffold, 8 mm in diameter and 2 mm in thickness, as co-culture group. Chondrocytes and ADSCs with the same cell number were seeded respectively onto the scaffold as positive control group and negative control group. 200 microl chondrocytes (1.5 x 10(7)/ml) were seeded as low concentration chondrocyte group. There were 6 specimens in each group. All specimens were harvested after in vitro culture for 8 weeks in DMEM plus 10% FBS. Gross observation, histology, immunohistochemistry, wet weight measurement and glycosaminoglycan (GAG) quantification were used to evaluate the results. Multiple-sample t-test statistics analysis was done to compare the difference of wet weight and glycosaminoglycan(GAG) content between the groups. RESULTS: Cells in all groups had fine adhesion to the scaffold and could secrete extracellular matrix. In co-culture group and positive control group, cell-scaffold constructs could maintain the original size and shape during in vitro culture. At 8 weeks, cartilage-like tissue formed in gross appearance and histological features, and abundant type II collagen could be detected by immunohistochemistry. Wet weight and glycosaminoglycan(GAG) content of co-culture group were respectively (174 +/- 12) mg and (7.6 +/- 0.4) mg. There were respectively 75% (P < 0.01) and 79% (P<0.01) of those of positive control group. In negative control group, however, constructs shrunk gradually without mature cartilage lacuna in histology. In low concentration chondrocyte group, constructs also shrunk obviously with small amount of cartilage formation at the edge area of the construct, and wet weight was (85 +/- 5) mg, which was 37% (P<0.01) of that of positive control group. CONCLUSIONS: Chondrocytes can provide chondrogenic microenvironment to induce chondrogenic differentiation of ADSCs and thus promote the in vitro chondrogenesis of ADSCs.

Tissue engineering and stem cell application of urethroplasty: from bench to bedside.

OBJECTIVE: To review the advances in the basic research and clinical application of tissue engineering and stem cell technology in urethral reconstruction. Urethral defects resulting from congenital malformations, trauma, inflammation, or cancer are a common urologic issue. Traditional urethral reconstruction is associated with various complications. Tissue engineering and stem cell technology hold novel therapeutic promise for urethral reconstruction. METHODS: One of us searched the PubMed database (January 1999 to January 2011) using the English search terms "tissue engineering," "stem cells," "urethral reconstruction," and "urethra." A total of 86 reports were retrieved. After the repetitive and irrelevant reports were excluded, 40 were included in the final analysis. The review outlined and evaluated the advances in basic research and clinical application and the current status and prospects of tissue engineering and stem cell technology in urinary reconstruction. RESULTS: Two therapeutic strategies are available for urethral reconstruction using tissue engineering: the acellular matrix bioscaffold model and the cell-seeded bioscaffold model. The acellular matrix bioscaffold model has been successfully used in the clinic and the cell-seeded bioscaffold model is making its transition from bench to bedside. CONCLUSION: Stem cells can provide the seed cells for urologic tissue engineering, but much basic research is still needed before their clinical use is possible.

[Influence of in vivo or vitro microenvironment on the mechanical properties and histological structure of tissue engineered cartilage].

OBJECTIVE: To investigate the influence of in vivo or vitro microenvironment on the mechanical properties and histological structure of tissue engineered cartilage, and to provide the appropriate parameters for cartilage construct in vitro. METHODS: Human fetal articular chondrocytes were cultured and expanded in vitro, the passage 2 chondrocytes were seeded at the density of 6 x 10(7) cells/cm3 to cylindric dimensional scaffolds made by polyglycolic acid (PGA) and polylactic acid (PLA). These constructs were cultured in vitro for 4 weeks. After 4 weeks, part of samples were implanted subcutaneously into nude mice for 6 and 12 weeks, the others continued to be cultured in vitro. All specimens were harvested after 6 and 12 weeks, and evaluated by gross observation, histology, histochemistry, ultrastructure and mechanical test. RESULTS: All specimens in vivo and vitro eventually formed good shape hyaline cartilage. The constructs in vivo group was white color with smooth surface, and had better mechanical properties than those in vitro, by TEM we can observe the thick and striated collagen fibers in regularly arranged collagen fibril which was similar to adult articular cartilage. The constructs in vitro group was yellow color with coarse surface, the appearance and ultrastructure was similar to fetal articular cartilage. Specimens implanted for 12 weeks in vivo had better compressive modulus(38.28 +/- 3.95) MPa and collagen diameter (41.58 +/- 2.78) nm than those cultured in vitro at the same time (4.12 +/- 0.63) MPa, (15.83 +/- 1.70) nm (P < 0. 01). CONCLUSIONS: The structure and function of human tissue engineered cartilage became mature gradually from vitro to vivo, thick and striated collagen fibrils net similar to adult articular cartilage can be formed in constructs of vivo group,increased collagen cross-linking might be the reason that their mechanical properties been greatly improved.

[The study on the role of the soluble factors secreted by engineered cartilage in inducing bone marrow stromal cells chondrogenesis].

OBJECTIVE: To study the role of the soluble factors secreted by tissue engineered cartilage in promoting bone marrow stromal cells (BMSCs) chondrogenesis as an important aspect. METHODS: Porcine BMSCs, chondrocytes and dermal fibroblasts were respectively in vitro expanded and then seeded onto the polyglycolic acid/polylactic acid (PGA/PLA) scaffold. After 3 days, they were indirectly co-cultured by transwell. BMSCs-scaffold constructs were co-cultured with chondrocytes-scaffold constructs as experiment group (Exp), while co-cultured with fibroblasts-scaffold constructs as control group. BMSCs with the same cell number were seeded onto the scaffolds as another control group. There were 3 specimens in each group. All specimens were harvested after in vitro indirect co-culture for 8 weeks. Gross observation, histology, immunohistochemistry and RT-PCR were used to evaluate the results. RESULTS: The BMSCs-scaffold constructs co-cultured with chondrocytes-scaffold shrunk gradually during in vitro culture, but formed the mature lacuna structures and metachromatic matrices, collagen II expression could be observed by immunohistochemistry and RT-PCR examination. In the control group, the constructs shrunk greatly during in vitro culture and showed mainly fibrous tissue. CONCLUSIONS: The soluble factors secreted by chondrocytes can solely induce chondrogenic differentiation of BMSCs and thus promote the in vitro chondrogenesis of BMSCs.

Reconstruction of lymph vessel by lymphatic endothelial cells combined with polyglycolic acid scaffolds: a pilot study.

Restoration of lymphatic drainage using lymph vessels or tissue grafting is becoming an efficient method for alleviating obstructive lymphedema. However, the lack of ideal lymphatic grafts is the key problem that limits the application of lymphatic transplantation, but now that may be resolved with tissue-engineered lymph vessels. In this study, the feasibility of reconstructing lymph vessels was explored using lymphatic endothelial cells (LECs) combined with polyglycolic acid (PGA) scaffolds. The highly purified human dermal LECs can be isolated from human dermis by immunomagnetic bead sorting and multiplied in culture. The viability and growth potential of subcultured LECs make it possible to obtain large amount of cells in vitro. Light and scanning electron microscopy (SEM) showed that the prefabricated PGA scaffolds, with three-dimensional structure, can support cell adhesion, growth and spreading. The constructs formed with LECs combined with PGA scaffolds were cultured in vitro for 10 days and then implanted subcutaneously into nude mice. Six weeks after implantation, the portions of implanted tubules were harvested. Gross and histological observation demonstrated that the tubular structure still remained in the experimental groups but not in the control groups. Immunohistochemical staining and RT-PCR assay of the implanted vessels revealed positive staining in experimental groups for the lymphatic specific markers Podoplanin, VEGFR-3 and LYVE-1. The results indicate that LECs can serve as seed cells and be successfully combined with PGA scaffolds, and the tissue-engineered tubular structure using implanted LECs-PGA compounds showed preliminary characteristics of lymph vessels. A gap between the nearly normal or functional lymph vessel still exists as we have only the endothelial cell-lined duct, but this study demonstrates that it is feasible to construct tissue-engineered lymph vessels using LECs combined with a biodegradable material.

[Repair of calvarial defects with human umbilical cord blood derived mesenchymal stem cells and demineralized bone matrix in athymic rats].

OBJECTIVE: To investigate the feasibility of using human umbilical cord blood derived mesenchymal stem cells (UCB-MSCs) and demineralized bone matrix (DBM) scaffolds to repair critical-sized calvarial defects in athymic rats. METHODS: Human UCB-MSCs were isolated, expanded and osteogenically induced in vitro. Osteogenic differentiation of UCB-MSCs was evaluated by Alizarin Red staining and measurement of calcium content respectively, and then the cells were seeded onto DBM scaffolds. Bilateral full-thickness defects (5 mm in diameter) of parietal bone were created in an athymic rat model. The defects were either repaired with UCB-MSC/DBM constructs (experimental group) or with DBM scaffolds alone (control group). Animals were harvested at 6 and 12 weeks post-implantation respectively, and defect repair was evaluated with gross observation, micro-CT measurement and histological analysis. RESULTS: Micro-CT showed that new bone was formed in the experimental group at 6 weeks post-implantation, while no sign of new bone formation was observed in the control group. At 12 weeks post-transplantation, scaffolds had been degraded almost completely in both sides. It was shown that an average of (78.19 +/- 6.45)% of each defect volume had been repaired in experimental side; while in the control side, only limited bone formed at the periphery of the defect. Histological examination revealed that the defect was repaired by trabecular bone tissue in experimental side at 12 weeks, while only fibrous connection was observed in the control group. CONCLUSIONS: Tissue-engineered bone composed of osteogenically-induced human UCB-MSCs on DBM scaffolds could successfully repair the critical-sized calvarial defects in athymic rat models.

Use of tissue engineering in treatment of the male genitourinary tract abnormalities.

INTRODUCTION: A variety of congenital and acquired male genitourinary tract abnormalities can lead to organ damage or tissue loss that requires surgical reconstruction. Traditional reconstructive methods do not produce consistent satisfactory structural or functional replacement and may damage the genitourinary tract. Tissue engineering provides a promising alternative for the treatment of these disorders. AIM: The aim of this article is to provide an update on clinical and experimental evidence concerning the application of tissue engineering to treatment of abnormalities in the male genitourinary tract system. METHODS: A PubMed search was performed to retrieve relevant clinical and basic literature. MAIN OUTCOME MEASURES: The topics discussed in this review include the experimental and clinical application of tissue engineering for reconstruction of the urethra, penis, testis, and prostate. RESULTS: Tissue engineering techniques can provide a plentiful source of healthy tissue for reconstructive purposes. Acellular matrix scaffold and seed cells are two key elements in tissue engineering. Proper employment of seed cells and scaffold material may result in synergistic effects. Moreover, new tissue engineering technologies are being transferred from the laboratory to clinical practice. CONCLUSIONS: Tissue engineering provides biological substitutes that can restore and maintain normal function in diseased and injured tissues, thus providing an effective technique for regeneration of the male genitourinary tract.

[A pilot study of three dimensional printing of human bone marrow stem cells (hBMSCs)].

PURPOSE: To establish a three-dimensional biological printing technique of hBMSCs. METHODS: The hBMSCs were regularly isolated and cultured, and adjusted to the density of 1x10(6)/mL single cell suspension. Then these cells were labeled by PI fluorescence marker, and transferred by rapid prototype biological printer. Deposition spots were 300microm apart at X-axis, 500microm at Y-axis, 50microm at Z-axis, and then observed by laser confocal microscope. RESULTS: This technique could deposit cells with good spatial control. In three-dimensional layer, each "cell ink" drop contained 15-35 hBMSCs post-transfer, and achieved accurate distribution with spots distributed 300microm apart at x-axis, 500microm at y-axis and 50microm at Z-axis. CONCLUSIONS: This study indicates that hBMSCs can be effectively delivered by a rapid prototype printer with speed and accuracy. Application of three dimensional printing is of great importance in tissue engineering bone.

Repair of canine mandibular bone defects with bone marrow stromal cells and coral.

Tissue engineering has become a new approach for repairing bone defects. Previous studies indicated that coral scaffolds had been utilized with bone marrow stromal cells (BMSCs) in a variety of approaches for bony reconstruction. In these applications, the degradation rate of the material did not match the rate at which bone was regenerated. In this study, a previously established 30 mm long mandibular segmental defect was repaired with engineered bone using green fluorescent protein-labeled osteogenic BMSCs seeded on porous coral (n = 12). Defects treated with coral alone (n = 12) were used as an experimental control. In the BMSCs/coral group, new bone formation was observed from 4 weeks postoperation, and bony-union was achieved after 32 postoperative weeks. The residual coral volume of the BMSCs/coral grafts at 12 weeks (20-30%) was significantly higher than that at 32 weeks (10-15%, p < 0.05), which was detected by microcomputed tomography and histological examination. The engineered bone with BMSCs/coral achieved satisfactory biomechanical properties at 32 weeks postoperation, which was very close to that of the contralateral edentulous mandible. More importantly, immunostaining demonstrated that the implanted BMSCs differentiated into osteoblast-like cells. In contrast, minimal bone formation with almost solely fibrous connection was observed in the group treated with coral alone. Based on these results, we conclude that engineered bone from osteogenically induced BMSCs and biodegradable coral can successfully repair the critical-sized segmental mandibular defects in canines and the seeding cells could be used for bony restoration.

[Tissue-engineering bone with ADSCs and coral scaffold for repairing of cranial bone defect in canine].

OBJECTIVE: To investigate the application of tissue-engineering bone with ADSCs (adipose-derived stem cells) and coral scaffold for repairing of cranial bone defect in canine. METHODS: Autologous ADSCs isolated from canine subcutaneous fat were expanded, osteogenically induced, and seeded on coral scaffolds. Bilateral full-thickness defects (20 mm x 20 mm) of parietal bone were created (n = 7). The defects were either repaired with ADSC-coral constructs (experimental group) or with coral alone (control group). Radiological, gross, biomechanical and histological observations were done to evaluate the bone regeneration. RESULTS: Three-dimensional CT scan showed that new bones were formed in the experimental group at 12 weeks after implantation, while coral scaffolds were partially degraded in the control group. By radiographic analysis at 24 weeks post-transplantation, it showed that an average repair percentage of each defect was (84.19 +/- 6.45)% in experimental group, and (25.04 +/- 18.82)% in control group (P < 0.01). The maximum compression loading was (73.45 +/- 17.26) N in experimental group, and (104.27 +/- 22.71) N in control group (P <0.01). Histological examination revealed that the defect was repaired by typical bone tissue in experimental group, while only minimal bone formation with fibrous connection in the control group. CONCLUSIONS: The tissue-engineering bone with autologous osteogenic ADSCs and scaffold could successfully repair the cranial defects in canine models.