Xenopus Paraxial Protocadherin (PAPC), which was initially identified in a screen for genes present in the Spemann organizer of Xenopus embryos, is required for gastrulation, somitogenesis and otic vesicle formation. In order to investigate its function in various developmental events, an antibody was prepared which could specifically recognize Xenopus PAPC. Glutathione S transferase (GST) expression system was used to express the fusion protein GST-PAPC. Rabbits were immunized with GST-PAPC Western blotting analysis of FL-PAPC transfected HEK 293T cells lysates, which could be specifically blocked by pre-adsorption of prokaryotic expressed GST-PAPC fusion protein. Furthermore, by using immunofluorescence analysis the polyclonal antibody recognized membrane-bound PAPC in FL-PAPC transfected 293T cells and Xenopus animal cap cells. By Western blotting analysis,the endogenous 150 ku PAPC protein was detected in Xenopus embryos using the anti-PAPC antibody. Take together it could be concluded that a polyclonal antibody specifically against Xenopus PAPC was developed.

Objective To explore oropharyngeal swallowing disorders with videofluoroscopic swallowing study (VFSS). Methods 16 patients with dysphagia accepted VFSS with 10 ml of thin barium meal (50% w/v), thick barium meal (270% w/v), biscuit coated with thick barium meal in single swallow. Their swallowing function was observed on the lateral and anterior/posterior planes, including: symmetry of pyriform sinuses, oral transit time, presence of pharyngeal delay, pharyngeal transit time, oral and pharyngeal residue, and presence of aspiration.Results 5 patients demonstrated oral swallowing disorder. 3 patients demonstrated pharyngeal swallowing disorders, that was pharyngeal delay which caused in aspiration after swallowing. 8 patients demonstrated oropharyngeal swallowing disorders, and 3 of them presented aspiration,2 patients were silent aspirators, 1 was aspiration before and 1 after swallowing. The aspiration time could not be judged from the videofluoroscopy in the other one. For 4 patients with aspiration, 3 were severe, with more than 25% of the bolus aspirated, and 1 aspirated less than 5%. Conclusion VFSS can be helpful to plan individual rehabilitation.

Objective To investigate the synergistic effects of simulated microgravity and noise on the audito‐ry functions and corti organs in rats .Methods A total of 48 healthy rats were randomly divided into 4 groups (n=12):control group (Group A) ,microgravity only group (Group B) ,noise only group (Group C) and microgravity+noise group (Group D) .The microgravity environment was simulated by suspending the posterior limb using Morey-Holton method .The noise exposure was the simulation of the noise environment in spaceship including steady -state noise (72 ± 2) dB SPL and impulse noise up to 160 dB SPL .The control group was kept in normal conditions without any exposure .Auditory brainstem responses (ABRs) ,HE stainings ,immunofluorescence stainings and scanning electron microscopes (SEMs) were tested after 1week and 2 weeks exposure respectively (n=6) .Results The average of ABR threshold shifts of 2 weeks exposure were higher than those of 1 week in each group .Group D showed the highest ABRs (P<0 .01) .The HE stainings showed different degrees of injury in corti organs in all experimental groups ;which Group D being the most serious ,followed by Group C .The results of immunefluorescence in hair cells showed that swelling necrosis was the main damage of cochlear hair cell after 1 week's exposure .The swelling rate of Group D was the highest ,followed by Group C .Nucleus missing in hair cells was observed after 2 weeks'exposure . Group D had the highest missing rate and the main missing of Group B happened in the inner hair cells .SEM showed that the most serious damage of stereociliums in Group D ,followed by Group C ,then Group B .Conclusion The synergistic effects of simulated microgravity and noise lead to significant damage of the auditory function and cochlea Corti organs in rat .

Objective]To study the feasibility of Cartilage engineering using fibrin gel and chondrocyte cell sheets.[Methods]rabbit auricular chondrocytes were isolated and cultured to form cell sheets in flasks. The cell sheets were harvested using cell scrapers,and cut into fragments. The two precursor solutions of Fibrin gel were used to suspend the cell sheet fragments and isolated chondrocytes,and then added into the wells of a 48-well plate to form Gelatinous chondroid disc constructs. After in vitro culture, the constructs were implanted into nude mice. After 8 weeks,the constructs were harvested,and the specimens were evaluated using grossly observing, histological and immunohistochemical observation. [Results]Mature cartilage discs were obtained. The histomorphology of the explanted discs appeared non-uniform cartilaginous tissue comprise of regenerated cartilage islands with different size and irregular shape. Immunohistochemistry staining demonstrated that type II collagen highly expressed in the ECM of the cartilage islands. In 1 of the 8 discs,partial ossification was observed.[Conclusion]Fibrin gel is a favourable carrier. Artificial cartilage with stereochemical structure was constructed via combining the fibrin gel and chondrocyte cell sheets.

Objective: To observe the morphological changes on cochlear hair cells of rats in simulated weightlessness and inboard noise and to investigate the different changes in three turns of hair cells.Methods: Thirty-two healthy SD rats, all males, were randomly divided into four groups: control group, weightlessness group, noise group and weightlessness+noise groups (n=8).Then rats were exposed to-30° head down tilt as simulated weightlessness and inboard noise including steady-state noise which was (72±2) dB SPL and impulse noise up to 160 dB SPL in spaceship environment.The control group was kept in normal condition for 8 weeks.Bilateral auditory brainstem response (ABR) thresholds were tested before and after exposure respectively, and immunofluorescence staining and scanning electron microscopy (SEMs) of basilar membrane were applied after exposure.Results: ABR threshold shifts of each group were higher after exposure.There was difference between ABRs of the experiment groups before and after exposure (P<0.05).IF showed that the inner hair cells (IHCs) missing was the main damage in the basal turn of weightlessness group, the hair cells in the middle turn were swell and in the top turn, the hair cells were not clear.In noise group, the main loss happened in the outer hair cells (OHCs) of the outermost layer.In weightlessness+noise group, the nuclear missing in the basal turn was apparent, and mainly happened at the outermost layer.Meanwhile, the missing of hair cells in the middle turn and top turn was seen at the innermost layer.SEM showed that the cilia in the basal turn of weightlessness group were serious lodging, and occasional absence.Furthermore, the basal cilia in noise group became lodged and absent, and the other two turns were seriously missing.And in weightlessness+noise group, the cilia missing in the basal turn was apparently seen.The damage degree of the four groups: weightlessness+noise group>noise group>weightlessness group>control group and the damage degree of the four turns of hair cells: basal turn>mid turn>top turn.Conclusion: The rats exposed to the above environment for 2 weeks displayed obvious changes in cochlea morphology, and the weightlessness+noise group had the most obvious damage.

BACKGROUND:To seek for ideal scaffold materials is still an important task for cartilage tissue engineering.OBJECTIVE:To investigate the application of the AviteneTM microfibrillar collagen hemostat sponge in cartilage tissue engineering.METHODS:Rabbit auricular cartilage was harvested via surgical operation,and primary chondrocytes were isolated and amplified.Microfibrillar collagen hemostat sponge was cut into small bricks.The passage 2 chondrocytes were suspended and seeded onto the spongy bricks.After 1 week of in vitro culture,the constructs were then implanted into nude mice.After 8 weeks,the specimens were collected and evaluated using gross,histological and immunohistochamical observation.RESULTS AND CONCLUSION:During the cell seeding,the scaffold maintained its dimensions.No shrinkage was observed when the cell suspension was added.There was no considerable change in dimensions during the 1-week in vitro culture and at 8 weeks after implantation in nude mice.At 8 weeks post-implantation,mature cartilage blocks were harvested,which were white,translucent,and flexible.Histologically,the constructs appeared to have typical mature cartilaginous tissues,with robust extracellular matrix secretion,in which the microfibrillar collagen was incompletely degraded.We conclude that the microfibrillar collagen is a favorable scaffold material for cartilage tissue engineering.

BACKGROUND:The cell-sheet technology, based on a temperature-responsive culture, has been drawing more and more attention;however, the temperature-responsive culture dish is quite expensive. Therefore, it is imperative to develop a substitutive technique.OBJECTIVE: To study the feasibility of cell-sheet ulturing using common culture dish, and investigate the chondrogenesis of the cell sheet. METHODS: A piece of nasal septal cartilage was adopted from a patient with deviation of nasal septum to extract primary chondrocytes that were then cultured and amplified. The passage 3 chondrocytes were used to construct ell sheets. Monolayer cell sheet was formed by intensive culturing and allowing the extracellular matrix secretion. Bilayer cell sheet was constructed by seeding passage 2 chondrocytes on the monolayer cell sheet. The cell sheets were harvested using cell scraper, their properties were investigated prior to plantation into nude mice to construct the tissue-engineered cartilage. RESULTS AND CONCLUSION: Both bilayer and monolayer cell sheets with soft tremellose structures showed no significant difference through naked eyes. The newly harvested cell sheets appeared to have good fluidity and gelation. Eight weeks after mplantation into the nude mice, mature cartilage blocks were obtained. Histologically, the cell sheets were thin films composed by layered chondrocytes and extracellular matrix. Glycosaminoglycan formation and type Ⅱ collagen expressions were observed in the cell sheets cultured in vitro. The explanted samples exhibited ature cartilaginous tissue at 8 weeks after implantation. Biochemical analysis showed that the DNA contents of the neocartilages were higher than those of native human costal cartilage, while the contents of glycosaminoglycan and hydroxyproline were similar to native human nasal septal cartilage. To conclude, the hondrocyte cell sheets are likely to be constructed and harvested successfully using common culture dish, and the cell sheets exhibit favourable chondrogenesis.

BACKGROUND:Rapid prototyping technique has been recently applied in the medical reconstruction and al ows the production of individual implant for patients with tissue defects, achieving an accurate repair.
OBJECTIVE:To repair discontinuous mandibular defects in dogs using rapid prototyped titanium plate in combination with autologous cancellous bone graft.
METHODS:Nine hybrid canines were used, and the skul was scanned using spiral CT. Then CT data were used to construct three-dimensional digital model, in which virtual partial mandibulectomy was performed, and an individualized bone-grafting plate was designed. A titanium plate was manufactured using rapid prototyping and titanium casting. Animal experiment was then performed. A 40-mm discontinuous defect in the right mandibular body was created in the involved dogs. The defect was restored immediately using the customized plate in combination with autologous cancellous iliac blocks. Sequential radionuclide bone imaging, biomechanical testing, three-dimensional microcomputed tomographic scanning, radiology and histological examination were used to evaluate the turnover of the grafts.
RESULTS AND CONCLUSION:A symmetric mandible was reconstructed using the rapid prototyped grafting plate. The grafted bone survived and got corticalized, while a fibrous intermedium was found between the bone graft and the plate. In the reconstruction of mandibular defects, optimal functional and aesthetic outcomes could be achieved using the rapid prototyped grafting plates.

OBJECTIVETo investigate the effects of the leaching liquids of 4 differents kinds of dental alloys (Au alloy, Ag-Pd alloy, Co-Cr alloy, Ni-Cr alloy) on apoptosis related gene and protein of fibroblast L929.

METHODSThe L929 cells of mouse were treated in vitro with leaching liquids of 4 different kinds of dental alloys, Au alloy (group A), Ag-Pd alloy(group B), Co-Cr alloy(group C) and Ni-Cr alloy(group D). The RPMI1640 cell medium containing 10% fetal calf serum was served as a control(group E). The effects of these alloys on the expression of caspase-3, 8, 9 of L929 cells were examined by reverse transcription-polymerase chain reaction (RT-PCR) and immunohistochemistry method. Results After 48 h culture, the mRNA levels of caspase-3 and caspase-9 demonstrated significant differences between the groups expect group A and group E. The mRNA levels of caspase-8 had no change in all groups. The expression of caspase-3 and caspase-9 were significant differences between the groups expect group A and C, group B and D. The expression of caspase-8 had no change in all grotps.

CONCLUSIONThe leaching liquids of 4 different kinds of dental alloys expect Au alloy may induce cell appotosis through mitochondrion pathway.

Objective To observe the early changes of related indexes after high dose of 60Co γ-ray irradiation on rhesus monkey hematopoietic system.Methods A total of 33 rhesus monkeys were randomly divided into normal control and different irradiation control group,rhesus monkeys in irradiation control group were given different doses(4,8,12 Gy) irradiation to establish acute radiation sickness(ARS) models.XE-2100 automatic blood cell analyzer detected the peripheral blood before and after the irradiation of 3,6,9,12,24,48,80 h.The rhesus monkeys were sacrificed to have a observation of sternum pathological changes at 6,48 and 80 h after 4,8,12 Gy 60Co γ-ray irradiation.Results The number of white blood cell in peripheral blood of the rhesus monkeys after 4 and 8 Gy 60Co γ-ray irradiation were lower than that before irradiation at 3 h after irradiation,as was significant increased at 6 h after irradiation,the highest values were 136.04%.and 221.38% after 9 h(with before irradiation values was 100.00%,the same below),become obviously drooped from 12 h after irradiation,show clearly temporary peak.But the number of white blood cell after 12 Gy 60Co γ-ray irradiation was significant increased at 6 h after irradiation,at the highest of 9 h,become obviously drooped from 12 h after irradiation.Peripheral blood neutrophile count was significant increased at 6 h after irradiation,at the highest of 9 h,become obviously drooped from 12 h after irradiation.Peripheral blood lymphocyte count fell sharply after irradiation,3 h detection value was only 12.02%-25.04% of before irradiation.Sternal bone marrow nucleated cell number decreased sharply after irradiation,the more irradiation dose,the less residual hematopoietic cells.Conclusion In the early stage of BM-ARS,temporary peaktime node of the white blood cell and neutrophil count could be regarded as the best delivery time of hematopoietic cytokine therapy.