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Tan C.-Q.,Nanjing University of Technology | Tan C.-Q.,Nanjing Medical University | Gao X.,Nanjing Medical University | Guo L.,Nanjing Stomatological Hospital | Huang H.,Nanjing University of Technology
BioMed Research International | Year: 2014

Bone marrow mesenchymal stem cells (BMSCs) expressing recombinant IL-4 have the potential to remediate inflammatory diseases. We thus investigated whether BMSCs expressing exogenous IL-4 could alleviate autoimmune sensorineural hearing loss. BMSCs isolated from guinea pigs were transfected with recombinant lentivirus expressing IL-4. A total of 33 animals were divided into three groups. Group A received scala tympani injection of IL-4-expressing BMSCs, and Group B received control vector-expressing BMSCs, and Group C received phosphate-buffered saline. The distribution of implanted BMSCs in the inner ears was assessed by immunohistochemistry and fluorescence microscopy. Auditory brain-stem response (ABR) was monitored to evaluate the auditory changes. Following BMSCs transplantation, the threshold levels of ABR wave III decreased in Groups A and B and significant differences were observed between these two groups P < 0.05. Transplanted BMSCs distributed in the scala tympani and scala vestibuli. In some ears with hearing loss, there was a decrease in the number of spiral ganglion cells and varying degrees of endolymphatic hydrops or floccule. Following transplantation, the lentivirus-infected BMSCs migrated to the inner ear and produced IL-4. Our results demonstrate that, upon transplantation, BMSCs and BMSCs expressing recombinant IL-4 have the ability to remediate the inflammatory injury in autoimmune inner ear diseases. © 2014 Chang-qiang Tan et al. Source

Yuan T.,Nanjing University of Aeronautics and Astronautics | Liao W.,Nanjing University of Aeronautics and Astronautics | Dai N.,Nanjing University of Aeronautics and Astronautics | Cheng X.,Nanjing University of Aeronautics and Astronautics | Yu Q.,Nanjing Stomatological Hospital
International Journal of Biomedical Imaging | Year: 2010

An integrated single-tooth modeling scheme is proposed for the 3D dental model acquired by optical digitizers. The cores of the modeling scheme are fusion regions extraction, single tooth shape restoration, and single tooth separation. According to the valley shape-like characters of the fusion regions between two adjoining teeth, the regions of the 3D dental model are analyzed and classified based on the minimum curvatures of the surface. The single tooth shape is restored according to the bioinformation along the hole boundary, which is generated after the fusion region being removed. By using the extracted boundary from the blending regions between the teeth and soft tissues as reference, the teeth can be separated from the 3D dental model one by one correctly. Experimental results show that the proposed method can achieve satisfying modeling results with high-degree approximation of the real tooth and meet the requirements of clinical oral medicine. Copyright © 2010 Tianran Yuan et al. Source

Jiang M.,University of Sichuan | Yang Z.,Nanjing Stomatological Hospital | Feng B.,University of Sichuan | You M.,University of Sichuan | Wang H.,University of Sichuan
Journal of Voice | Year: 2015

Objective Velopharyngeal closure is an important physiological process contributing to the normal function of speech and swallowing. The aim of this study was to analyze the influence of sound intensity on velopharyngeal function in normal individuals. Materials and methods Lateral cephalograms of 38 volunteers obtained at rest and during phonation of vowel /i:/ at both high and low sound intensity were carefully analyzed. The digital sound level meter was used to evaluate and record the sound intensity of the phonation process. The angular and linear parameters on the lateral cephalograms were then measured to reveal the correlation between sound intensity and velopharyngeal closure. Results All the angular parameter values measured in the study were significantly greater in high sound intensity condition. As for linear parameters, all values were found to be significantly larger at high sound intensity, except for the effective velopharyngeal length and the vertical velopharyngeal length. A multiple linear regression model was set up to describe the correlation between the sound intensity, the effective velopharyngeal length, and velopharyngeal closure. With the increase of sound intensity and the decrease of the effective velopharyngeal length, the width of velopharyngeal closure is enlarged. Conclusions As one of the characteristic features of sound wave, the sound intensity was found to affect the objectively measured parameters of velopharyngeal closure on lateral cephalograms. © 2015 The Voice Foundation. Source

Zou D.,Tongji University | Han W.,Nanjing Stomatological Hospital | You S.,Tongji University | Ye D.,Shanghai JiaoTong University | And 7 more authors.
Cell Proliferation | Year: 2011

Objectives: Hypoxia-inducible factor 1α (HIF-1α) is a pivotal regulator of hypoxic and ischaemic vascular responses that drives transcriptional activation of hundreds of genes involved in vascular reactivity, angiogenesis and arteriogenesis. Previous reports based on gene knockout technology have demonstrated that HIF-1α can promote osteogenesis. However, this protein is easily degraded in a normoxic state, which makes in vitro studies of HIF-1α-induced mesenchymal stem cell (MSC) osteogenesis difficult. For better understanding of HIF-1α promoting osteogenesis, the role of HIF-1α-induced MSC osteogenesis in the normoxic state has been investigated here. Materials and methods: HIF-1α was made to overexpress using a lentiviral vector, and its effects on bone marrow-derived mesenchymal stem cell (BMSC) osteogenesis were investigated. Real-time quantitative and western blotting (to assess expression levels of angiogenic and osteogenic related genes regulated by Lenti-HIF-1α), alkaline phosphatase (ALP) and alizarin red-S staining analyses, were performed. Results: In HIF-1α gene-transfected BMSCs, expression levels of angiogenic, cartilaginous and osteogenic genes were all increased significantly compared to Lenti LacZ-transfected cells, at both mRNA and protein levels. ALP activity and alizarin red-S staining were significantly enhanced in HIF-1α transduced cells compared to control cells, on day 21. Conclusions: These results indicate that Lenti-HIF-1α can induce BMSC overexpression levels of angiogenic and osteogenic genes in vitro in the normoxic state. Further study will be focused on whether HIF-1α can also improve bone repair in vivo. © 2011 Blackwell Publishing Ltd. Source

Zou D.,Tongji University | Zou D.,Shanghai JiaoTong University | Zou D.,Anhui Medical University | Zhang Z.,Shanghai JiaoTong University | And 17 more authors.
Biomaterials | Year: 2012

The successful clinical outcome of the implanted tissue-engineered bone is dependent on the establishment of a functional vascular network. A gene-enhanced tissue engineering represents a promising approach for vascularization. Our previous study indicated that hypoxia-inducible factor-1α (HIF-1α) can up-regulate the expression of vascular endothelial growth factor (VEGF) and stromal-derived factor 1 (SDF-1) in bone mesenchymal stem cells (BMSCs). The angiogenesis is a co-ordinated process that requires the participation of multiple angiogenic factors. To further explore the angiogenic effect of HIF-1α mediated stem cells, in this study, we systematically evaluated the function of HIF-1α in enhancing BMSCs angiogenesis invitro and invivo. A constitutively active form of HIF-1α (CA5) was inserted into a lentivirus vector and transduced into BMSCs, and its effect on vascularization and vascular remodeling was further evaluated in a rat critical-sized calvarial defects model with a gelatin sponge (GS) scaffold. The expression of the key angiogenic factors including VEGF, SDF-1, basic fibroblast growth factor (bFGF), placental growth factor (PLGF), angiopoietin 1 (ANGPT1), and stem cell factor (SCF) at both mRNAs and proteins levels in BMSCs were significantly enhanced by HIF-1α overexpression compared to the invitro control group. In addition, HIF-1α-over expressing BMSCs showed dramatically improved blood vessel formation in the tissue-engineered bone as analyzed by photography of specimen, micro-CT, and histology. These data confirm the important role of HIF-1α in angiogenesis in tissue-engineered bone. Improved understanding of the mechanisms of angiogenesis may offer exciting therapeutic opportunities for vascularization, vascular remodeling, and bone defect repair using tissue engineering strategies in the future. © 2011 Elsevier Ltd. Source

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