The permeability of three kinds of membranes, including imported agarose (Sigma), China-made agarose and interpenetrating polymer network (IPN) made of Chinese agarose mixed with other synthetic macromolecular compound, to four substances with different molecular weights (methyl orange, Vit B12 , insulin and lysozyme) was studied. The results revealed that the solutes with molecular weights below 6 000 dalton could permeate all kinds of membranes with similar coefficient of permeability. However, the immunoisolation of IPN for such macromolecular solute, as lysozyme (14 300 dalton) was much more effective than that of other kinds, which only had limited effect of immunoisolation. These results suggest that IPN with the characteristics of efficacious immunoisolation fulfills the requirements for transplantation. 2 000-3 000 microencapsulated islets were transplanted intraperitoneally in six diabetic rats without the use of immunosuppressive drugs. On the 4th post-operative day, blood sugar dropped significantly until the 7th day, when it was in normal range. The normal level of blood sugar had remained for 30 days. The microcapsules, made of IPN, possesses a better function of immunoisolation, which may lay a foundation of treating IDDM with encapsulated porcine islet grafting.

Objective This study investigates feasibility of replacing urinary epidermal cells with foreskin epidermal cells to reconstruct engineered anterior urethra with acellular collagen matrix. Methods A cellular collagen matrices were generated from allogeneic rabbit bladder submucosa.In 6 rabbits,autologous foreskin epidermal cells isolated,in vitro expanded and labeled with Brdu before seeding onto a tubular collagen matrix of 2 cm long.In 12 male rabbits, urethral mucous defect was created and urethroplasty was performed with tubular collagen matrix seeded with epidermal cells (n=6) in experimental group or matrix without cells seeding (n=6) in control group.Urethrography was performed at 1,2,and 6 months postoperatively.Urethras grafts were harvested and analyzed grossly and histologically at the same time points. Results In control group, gross and urethrography demonstrated urethral stricture of repaired defects at all time points.Histology showed a single layer of epidermal cell with unorganized and crassitude muscle fiber bundles in submucosa layer.In contrast, urethrography showed a patency of repaired urethral defect with the maintenance of a wide urethral caliber in experimental group without sign of strictures at any time points. Histologically,the graft seeded with epidermal cell had a multi-layers epidermal cells by 1 month,which demonstrated the presence of a epidermal cells layer with a normal submucosa structure.The immunoflorescent staining of Brdu confirmed the presence of implanted epidermal cells.In addition, the implanted cells also express keratin when stained with anti-pancytokeratins AE1/AE3 antibody.At 2 month,histology showed relatively normal urethral architecture with vessel abundance in submucosa structure.The staining of Brdu showed decreased at implanted epidermal cells and epithelial phenotypes were confirmed immunocytochemically using pancytokeratins AE1/AE3.At 6 month,the graft structure show multi-layers epidermal cells without staining of Brdu. Conclusions Urethra reconstruction was better achieved with cell seeded acellular collagen matrix when compare with acellular matrices alone.Foreskin epidermal cells seems succeeded in replacing urethral epidermal cells for urethra reconstruction.

High level of glucose could induce apoptosis in human umbilical vein endothelial cells. C peptide and insulin had different effects on high glucose induced endothelial cells apoptosis. The reasonable application of C peptide may be helpful in preventing and treating diabetic macrovascular diseases.

Objective:To observe the effect of xylitol on the cyclooxygenase(COX)-2 expression of renal tubule in diabetic rats.Methods:The Wistar rats were randomly divided into normal control group(group NC),diabetes control group(group DC),5% xylitol-treated group(group 5%),10% xylitol-treated group(group 10%)and 20% xylitol-treated group(group 20%).At the end of 8 weeks,the expression of COX-2 in kidney tissue,the level of serum uric acid,allantoin and creatinine were tested in rat groups.Results:The levels of serum uric acid and allantoin were higher in group 5% and group 10% compared with that of group DC.The differences in levels of serum uric acid and allantoin were statistical significance between group 10% and group DC(P ＜ 0.05),whereas,the lower levels of serum uric acid and allantoin were found in group 20% compared with those of group DC(P ＞ 0.05).The levels of urine uric acid and allantoin were lower in group 5% and group 10% than those of group DC(urine uric acid,P＞ 0.05 and allantoin,P＜ 0.05),whereas,group 20% had higher levels of urine uric acid and allantoin than those of group DC(P＜ 0.05).The fractional excretion of uric acid(FEUA)was lower in group 5% and group 10% compared with that of group DC(P ＜ 0.05).The FEUA was higher in group 20% than that of group DC(P ＜ 0.05).The expression of COX-2 was significantly increased in group 5% and group 10% compared with that of group DC(P ＜ 0.05),but the expression of COX-2 decreased in group 20%(P ＜ 0.05).Conclusion:The lower and mediate doses of dietary xylitol could aggravate the tubular injury through increasing the level of serum uric acid and the expression of COX-2 in renal tubule.The higher doses of xylitol could increase the excretion of uric acid and down-regulate the expression of COX-2 in renal tubule.

BACKGROUND: A lot of researches have proved that polyglicolide acid (PGA), as a stent material, has been successfully used to construct engineered tissues, such as cartilage, bone and tendons, in nude mice or even big mammal. Whether the incubation of vascular endothelial cells and smooth muscle cells in the polyglicolide acid may subcutaneously construct vessel-like structure in nude mice needs a further study.OBJECTIVE: To verify the feasibility of forming vessel-like structure in the nude mice by subcutaneous implantation of polyglicolide acid cocultured with vascular endothelial cells and smooth muscle cells derived from newborn umbilical vein.DESIGN: Contrast study.SETTING: Tissue Engineering Key Laboratory, Medical College, Shanghai Jiao Tong University.MATERIALS: This study was performed at Tissue Engineering Key Laboratory, Medical College, Shanghai Jiao Tong University from January to June 2002. Belly band was derived from newborn babies in our department of obstetrics & gynecology. The parturien provided the informed consent, and this study was approved by the local research ethics committee. Twenty-six nude mice (3-4 weeks old, clean grade, irrespective of gender) were selected in this study. The animal experiment received confirmed consent from the local ethic committee. Polyglicolide acid was provided by Albany International Research Co.METHODS: Vascular endothelial cells and smooth muscle cells derived from newborn umbilical vein were incubated on a piece of polyglicolide acid to produce cell-material compound. In addition, the compound covered around the silicone tube to form a tube-like structural substance. Subsequently, the tube-like structural substance was subcutaneously implanted in 20 nude mice, which were regarded as an experimental group. And then, polyglicolide acid alone was subcutaneously transplanted in the rest 6 nude mice, which was regarded as a control group.MAIN OUTCOME MEASURES: Gross observations of cell-material compound by 2 and 6 weeks after transplantation;HE staining and immunohistochemical staining.detection; expression of factor Ⅷ and α-smooth muscle actin.RESULTS: Twenty-six nude mice were included in the final analysis. ① Gross observation: At 2 weeks after implantation,both the experimental and control groups formed tubular structures, however, at 6 weeks after implantation, the tubular structure still remained in experimental group but not in the controls. ② Histological observation and immunohistochemical detection: The histological examination of the engineered vessel showed that at 2 weeks, the vessels in both group contained mainly undegraded PGA fibers, while at 6 weeks, the PGA fibers were almost completely degraded in both groups and in the control group only fibrous-like tissue formed. Contrastly, in experimental group a typical vascular structure formed, Masson's trichrome stain, which stains collagen green, smooth muscle fibers red and cells purple, showed significant amounts of stainable collagen and smooth muscle fibers in the wall of the engineered vessel, furthermore,immunohistochemistry examination revealed that there were an endothelial cell layer formed in the inner surface of the engineered vessel which was confirmed by positive staining of yon Willebrand factor, meanwhile, the smooth muscle cells in the wall of the engineered vessel were confirmed by the positive staining of smooth muscle α-actin.CONCLUSION: The subcutaneous implantation of polyglicolide acid cocultured with vascular endothelial cells and smooth muscle cells may form vessels, which are similar to normal vascular histological structure.

OBJECTIVE To understand the synaptic remodel in inner ear after hearing injury by investigating growth associated protein 43(GAP-43) expression in the inner ear hair cells after exposed Kangmin mice to neural injury noise stimulation to induce permanent threshold shift(PTS) or temporary threshold shift(TTS).METHODS To compare the expressions of GAP-43 of NMDAR signal pathway during neural injury stimulation by immunocytochemistry.RESULTS The sustained GAP-43 increase occurs after 7d and 14d of PTS group,and there is not remarkable difference between them.Compared with normal control,the change is not significant in TTS group.CONCLUSION The increase of GAP-43 in spiral ganglion after 7d trauma reveals the synaptic remodel in inner ear.

OBJECTIVE Congenital aural atresia repair is difficult owing to unpredictable anatomy. Benefits may be gained from image-guided surgery(IGS) . its exact role and surgery indication were def ined. METHODS From 2001 to 2004,36 ears with bony type C(Schuknecht classification) congenital atresia were performed. In the IGS group(n=18) ,repair surgery was performed with IGS,while in the control group(Non-IGS,n=18) ,similar intervention was applied without IGS. IGS group:aged from 12-29 years,follow-up from 6 months to 1 year. Non-IGS group:aged from 10-27 years,follow-up from 6 months to 3 years. Intra-and post-operative clinical and audiometric findings were compared. RESULTS All of the patients had congenital bony aural atresia,ossicles malformation,tympanic cavity hypoplasia and facial nerve malformation. IGS revealed a malformed horizontal semicircular canal hidden in the bony atresia plate during the operation while computed tomography(CT) did not show preoperatively. IGS computed tomography images correlated well with intra-operative findings,gave the surgeon more securityand reduced operative time(2 hours and 24 minutes) by 25 minutes. The prepare time increased 20 minutes(15-30 minutes) ,but total time decreased 5 minutes in IGS group. The registration accuracy was 0.6-1.3 mm,average 0.84 mm,which was suitable for the otologic surgery. There were 1 case in IGS group and 3 cases in Non-IGS group happened local aural restenosis after operation. But there were no facial nerve paralysis and hearing injury happened in both groups,and all of the patients got the satisfactory hearing after the hearing reconstruction(the air-bone gap with an average of IGS is 31.8dB,Non-IGS is 30.5dB) . CONCLUSION In our estimation,IGS is valuable for type C congenital aural atresia repair. It serves as an educational tool and a guide both for the experienced and inexperienced surgeons in critical situations where anatomical landmarks are distorted and approach is limited. There is no statistically significant between two groups on hearing improvement after operation.

The effects of nanometer realgar suspension on proliferation and apoptosis of human uterine cervix cancer cell line SiHa cells and oncogenic genes HPV16E6/E7 were investigated. A "micro-jet efflux" strategy was used for the preparation of nanometer realgar suspension. SiHa cells were treated with nanometer Realgar suspension in various concentrations (6.25,12.5,25 and 50mg/L) for different durations (12,24,48 and 72h). The inhibitive effect of nanometer realgar suspension on growth of SiHa cells was detected by MIT method. Special morphological changes of apoptosis were observed by transmission electron microscopy (TEM) and DNA fragments electrophoresis. The apoptotic rate was quantified by flow cytometry (FCM). The expression of HPV16E6/E7 mRNA and protein was assayed by RT-PCR and Western blot respectively. The results showed after being treated with 25-50mg/L nanometer realgar suspension for 48h, the survival rate of SiHa cells was decreased, and apoptotic rate markedly increased in a time- and concentration-dependent manner. TEM and DNA electrophoresis revealed the special morphological changes of apoptosis. The apoptotic rate of SiHa cells treated with nanometer realgar suspension was significantly higher than in the control group (P<0.01), and G0/G1 phase arrest appeared following treatment with nanometer realgar suspension in 25 and 50mg/L for 48h.RT-PCR and Western blot assay indicated that nanometer realgar suspension reduced the HPV16E6/E7 gene expression. Nanometer realgar suspension could inhibit the proliferation and induce apoptosis of SiHa cells. The mechanism may be related to the down-regulation of the HPV16E6/E7 gene expression.

OBJECTIVE: To investigate the T helper cells (Th) predominant differentiation and the modulation of nuclear transcription factors kappa B (NF-kappaB) in middle ear of rat model of otitis media with effusion (OME). METHOD: Sixteen SD rats were randomly divided into OME (Exp group) and control group (Con group). The expression of NF-kappaB were observed by immunohistochemistry. The level of IFN-gamma and IL-4 in tympanic lavage fluid (TLF) were determined by ELISA. RESULT: As compared to the Con group , the level of IL-4 and the ratio of Th2/Th1 (IL-4/IFN-gamma) in TLF of Exp group significantly increased (P<0.05), when no significant difference in IFN-gamma levels in TLF was found. The ratio of NF-kappaB p65 positive cells to white cells in temporal bone marrow smears and middle ear mucosa of Exp group was significantly higher than that of Con group (P<0.05). The expression of NF-kappaB p65 in temporal bone marrow smears and middle ear mucosa was signficantly positively correlated with the concentration of IL-4 in TLF of Exp group (P<0.05). CONCLUSION The middle ear is capable of mounting an allergic response and subsequent formation of effusion. There is Thl/Th2 immune response imbalance, which polarizes toward Th2 response in the middle ear microenvironment of allergic OME rat model. Moreover , NF-kappaB may participate in regulating Th2 predominant reaction.
Animals ; Interleukin-4 ; metabolism ; Male ; NF-kappa B ; metabolism ; Otitis Media with Effusion ; chemically induced ; immunology ; metabolism ; Ovalbumin ; adverse effects ; Rats ; Rats, Sprague-Dawley ; Th1 Cells ; immunology ; Th2 Cells ; immunology

OBJECTIVE: To investigate the mechanism of hearing pathway NMDAR regulating the changes of phosphorylated c-Jun expression in spiral ganglion after exposed Kunming mice to neural injury noise stimulation to induce permanent or temporary threshold shift. METHOD: To compare the different expressions of the key components (phosphorylated C-Jun) of NMDAR signal pathway during neural injury stimulation by Immunohistochemistry in CG. RESULT: The levels of phosphorylated c-Jun remarkably, increased in the spiral ganglion after 8 h, 48 h, 7 d and 14 d following noise trauma induced permanent threshold shift (PTS), and the numbers of positive cells reduced gradually. The similar changes occur in mice treated with MK-801 30 minutes before and after 3 h trauma induced PTS. After 48 h of noise induced TTS, the expression of Phosphorylated c-Jun return the level of normal control. CONCLUSION The expressions of phosphorylated c-Jun are time-related and uniform in the time and position in CG after noise trauma. MK-801 can alleviate the damage of noise trauma by altered the NMDA receptor-mediated calcium influx. Therefore, the NMDA receptors may involved in the damage of inner ear in common.
Acoustic Stimulation ; Animals ; Auditory Threshold ; Cochlea ; metabolism ; Hearing Loss, Noise-Induced ; metabolism ; JNK Mitogen-Activated Protein Kinases ; metabolism ; Mice ; Mice, Inbred Strains ; Spiral Ganglion ; metabolism