BACKGROUND:There are some disadvantages in harvesting and transferring cells in the traditional tissue engineering technique,and it is difficult to form dense tissues,which significantly limits the development of tissue engineering.OBJECTIVE:To explore the culture and fabrication of dog bone marrow mesenchymal stem cell(BMSC)sheet in vitro.METHODS:Bone marrow was extracted from dogs following anesthesia.BMSCs were isolated with the method of density gradient centrifugation in vitro.BMSCs at passage 4 at a density of 1×10~9/L were incubated in the temperature-responsive culture dishes with a diameter of 3.5 cm,and cultured in an incubator at 37 ℃,5% CO_2 and saturated humidity.The temperature of the incubator was changed from to 37 V to 20 ℃ to prepare BMSCs cell sheet for 20 minutes.Cell morphological changes and cell sheet formation were observed under an inverted microscope.RESULTS AND CONCLUSION:Dog BMSCs following 24 hours of primary culture presented ellipse or polygonal shape.Most cells adhered at hour 72,and cell colonies were visible at day 7.Cells showed long spindle and completely confluence at day 12,with unclear boundary.BMSCs in the temperature-responsive culture dishes presented short spindle shape,and gradually separated from the dish bottom,forming entire cell sheet containing extracellular matrix at 20 V.These verified that dog BMSCs can be effectively obtained with method of density gradient centrifugation.Complete cell sheet layer can be fabricated with temperature-responsive culture dishes.

BACKGROUND: How to reconstruct tissue-engineered bone with structure similar to natural bone iS a problem in the development of tissue engineering. Cell sheet engineering technology enables novel approaches to construction of tissue-engineered bone. OBJECTIVE: To observe the biocompatibility of call sheets to decalcified bone matrix (DBM) and their growth on DBM. DESIGN, TIME AND SETTING: An in vitro observation was performed at the Central Laboratory, Affiliated Hospital, Qingdao University Medical College between June and September 2009.MATERIALS: Dog bone marrow stromal cell sheets were prepared using temperatura-responsive medium. Dog DBM was prepared by defatting, decalcification, and noncotlagen protein removal procedures. METHODS: DBM surface was covered by call sheets prepared by temperature-responsive technology and cultured with DMEM containing 10% fetal bovine serum and osteoinductive agent.MAIN OUTCOME MEASURES: Under scanning electron microscope, DBM structure, as well as the attachment and growth of cell sheets on DBM surface, was observed. Porosity and aperture size of DBM were calculated. RESULTS: DBM exhibited a three-dimensional latticed structure, with a porosity of approximately 75%. The mean aperture size was (250.11±98.89) μm, exhibiting a normal distribution. Cell sheets well attached to and grew on DBM surface, and rapidly proliferated.CONCLUSION: Cell sheets show good biocompatibility to DBM. DBM/cell sheets complex can be applied in tissue-engineered bones, which promotes the construction of tissue-engineered bone with structure similar to natural bone.

Objective:To predict Th/B cell epitopes in HA of influenza virus(H1N1) and analyze antigenicity of the candidate epitopes in order to develop epitope-bacterin by the way of bioinformatics.Methods:The HA amino acid sequences of influenza virus (H1N1),which the viral infection was prevalent recently,were downloaded from Genbank.The Th/B cell epitopes were predicted and analyzed by bioinformatics methods.Then,specificity and conservation of the candidate epitopes were estimated.Finally,antigenicity of the candidate epitopes was identified by influenza virus (H1N1) positive serum samples of mice.Results:Three Th/B cell epitopes containing HA73-87,HA125-139,HA188-205 were acquired.Two of the candidate epitopes were in a relatively conserved domain of HA1,and a deal of 2006-2009 influenza virus (H1N1) isolates contained the sequences.Moreover,the candidate epitopes were showedin a distinct antibody combining reactivity with the influenza virus (H1N1) positive serum of mice,which inferred the predicted epitopes to be functional ones.Conclusion:The selected epitopes are able to be functional HA Th/B cell epitopes of influenza virus (H1N1).Our study also establish the foundations for the further research of influenza virus infection and immunity mechanism,the recognition of influenza virus (H1N1) functional epitope and the development of epitope vaccines.

OBJECTIVEToday metal-ceramic restorations are widely accepted in dental practice because of their good aesthetic and biocompatible properties, but there are still several problems to be resolved, among which the influences of their margins on gingival health is noticeable. The purpose of this study was to investigate the influences of metal-ceramic restoration margin on gingival health.

METHODS129 abutments of metal-ceramic restorations, including their margins' fitness, location and smoothness were examined and their influences on gingival health were analyzed.

RESULTSThere was a close relation between the metal-ceramic restorations' margins and the gingival health.

CONCLUSIONIn order to maintain the gingival health, the margins should be smooth, closely fitted, no overhanging and in a moderate location (i.e. not below the gingival more than 1 mm).

Female ; Gingival Diseases ; etiology ; Gingivitis ; etiology ; Hemorrhage ; etiology ; Humans ; Male ; Metal Ceramic Alloys ; adverse effects

OBJECTIVEThe aim of this study was to rebuild the anatomic structures of the mandibular bone and the canal, and to testify the reliability of the rebuilt model.

METHODS15 mandibular bones with teeth are chosen, and a three-dimensional model was built with the method of CT. The slices vertical to the compensating curve were made in every dental position. Then the authors collected the data of alveoli and mandibular canal in every slice. The same work was done to the bone specimen, and then comparative analysis was done.

RESULTSThe wideness of the alveoli and 10 mm bellow increased from mesial to distal position. It was the same of the alveoli from the top to the bottom. The mandibular canal lied in the inner and inferior side of the mandibular body. There was no significant difference in data collected with these two methods.

CONCLUSIONDifferent types of dental implants should be chosen according to the anatomic characteristic of the mandibular bone in every dental position before the operation to avoid complications. And a reliable, accurate and direct method of planning an implant operation is to rebuild a three-dimensional model.

Adult ; Computer Graphics ; Humans ; Mandible ; anatomy & histology ; diagnostic imaging ; innervation ; Mandibular Nerve ; anatomy & histology ; Models, Anatomic ; Tomography, Spiral Computed ; methods

Objective:To predict Th/B cell epitopes in HA of influenza virus(H1N1)and analyze antigenicity of the candidate epitopes in order to develop epitope-bacterin by the way of bioinformatics.Methods:The HA amino acid sequences of infiuenza virus(H1N1),which the viral infection was prevalent recently,were downloaded from Genbank.The Th/B cell epitopes were predicted and analyzed by bioinformatics methods.Then,specificity and conservation of the candidate epitopes were estimated.Finally,antigenicity of the candidate epitopes was identified by influenza virus(H1N1)positiVe serum samples of mice.Results:Three Th/B cell epitopes containing HA_(73-87),HA_(125-139),HA_(188-205) were acquired Two of the candidate epitopes were in a relatively conserved domain of HA1,and a deal of 2006-2009 influenza virus(H1N1)isolates contained the sequences.Moreover,the candidate epitopes were showedin a distinct antibody combining reactivity with the influenza virus (H1N1)positive serum of mice,which inferred the predicted epitopes to be functional ones.Conclusion:The selected epitopes are able to be functional HA Th/B cell epitopes of influenza virus(H1N1).Our study also establish the foundations for the further research of influenza virus infectlon and immunity mechanism,the recognition of influenza virus(H1N1)functional epitope and the development of epitope vaccines.

177Lu-prostate specific membrane antigen(PSMA)radio-ligand therapy has been approved abroad for advanced prostate cancer and has been in several clinical trials in China.Based on domestic clinical practice and experimental data and referred to international experience and viewpoints,the expert group forms a consensus on the clinical application of 177Lu-PSMA radio-ligand therapy in prostate cancer to guide clinical practice.

OBJECTIVE To systematically review the background of bioequivalence assessment of nasal sprays and nasal aerosols and the guiding considerations for the bioequivalence assessment of these complex drug-device combination products by regulatory authorities in the United States, the European Union(EU) and China. METHODS This article provided detailed explanations on the innovative weight of evidence assessment approach adopted by the US Food and Drug Administration(FDA), and the statistical rationale, methods and considerations for the bioequivalence assessment of nasal sprays and nasal aerosols. Using the calculation methods described in the draft guidance for budesonide inhalation suspension and the draft guidance for fluticasone nasal spray propionate issued by FDA, the statistical parameters of two-sided and one-sided population bioequivalence calculation were realized through R language programming, and pseudo-code for the population bioequivalence (PBE) calculation programs was provided. This article also presented a comprehensive review of published guidelines and summaries review principles of the EU and China for nasal sprays and nasal aerosols equivalence assessment. RESULTS & CONCLUSION Nasal sprays/nasal aerosols is the focus of innovative and generic drug development in recent years. This paper provided valuable considerations references for the research and development, quality control and bioequivalence evaluation of generic preparations of nasal sprays/nasal aerosols.