Objective To study the effect of transforming growth factor β1 (TGF-β1) plasmid on poly frosted-defrosted allogenic nerve transplantation. Methods Forty Wistar rats were randomly divided into two groups equally. A 2.0 cm sciatic nerve segment, 5 mm away from infrapiriformis muscle space, was removed and the defect was repaired with poly frosteddefrosted allogenic nerve. The TGF-β1 plasmids were injected into the nerve anastomosis and adjacent muscles in the experimental group, normal saline in the control group. The nerve specimens were sectioned for staining in the 6th and 12th weeks . Axonal count and statistical analyses were done. Results The grafted and distal nerve segments showed regenerated fibers in both groups. In the experimental group,less edema and more nerve fibers were observed in the 6th week. The grafted nerve segment was filled with regeneration axons, the myelinated nerve fibers arranged regularly, and the axons and the myelin sheaths developed well in the 12th week. There was significant difference in the number of regenerating axons between the experimental group 98.6±4.8／μm2 and control group 75.8±5.1／μm2 (Plt;0.01). Conclusion Multiple frost-defrost of allogenic nerve can reduce its antigenicity and increase itsusefulness in repairing nerve defects. Local use of TGF-β1 plasmid can enhance immunosuppression to reduce immuno rejection.
OBJECTIVE: To investigate the changes of fibroblast growth factor (FGF) in burn wounds. METHODS: The FGF expression in the center of wound granulation, the edge of wound, the healed part of wound, the normal skin of patients, and the heal course of second degree burn wounds were detected by immunohistochemical methods. RESULTS: The expression intensity of FGF was different in the different sites of third degree burn wounds. The highest contents of FGF was in the center granulation of burn wounds, the less was in the borderline of wound and healed skin, and the least was in the healed skin. FGF expression mainly concentrated in the middle layer of wound, and almost no FGF expression in normal skin. The most FGF expression was occurred at 14 days after injury in second degree of burn wound. CONCLUSION: The changes of FGF in wounds are closely related to the wound healing, and rational use of FGF can promote wound healing.
Objective To establish a better method of isolating andculturing ofneural stem cells(NSCs) in neonatal rat brain. Methods Tissue of brain was isolated from neonatal rats. Different medium and culture concentration were used toculture NSCs of neonatal rat. The culture concentration used were 1×10 4, 1×105, 1×106and 1×107/ml respectively. Ingredient of medium was classified into group 1 to 8 respectively according to whether to add 2% B27, epidermal growth factor (EGF) and basic fibroblast growth factor (bFGF) as well as the difference in culture concentration. The cells were induced to differentiate asto be confirmed as NSCs, and then were checked by phase contrast microscopy and identified by immunocytochemistry. Results The cells isolated and cultured gathered into neurospheres. The cells were capable of proliferating and maintaining longterm survival in vitro. The cells could be differentiated into neurons and glia.It was to the benefit of the survival of NSCs to add 5% fetal bovine serum(FBS)into the medium at the beginning of the culturing. When 10% FBS was added intothe medium, the neurospheres differentiated quickly. When concentration 1×106/ ml was used, the growth rate of the cells was the highest of all the concentrations. Reasonably higher cell concentration promoted the proliferation of NSCs. It was necessary to add 2% B27, EGF, and bFGF into the medium. The cells had the best growth when 2% B27, 20 ng/ml bFGF and 20 ng/ml EGF were added into the culture medium. EGF and bFGF had cooperative effect. Conclusion A better method of isolating and culturing of NSCs in neonatal rat brain is established and the foundation for future research is laid.
OBJECTIVE To study the immunosuppressive effect of combined therapy with FK506 and RS-61443 in rat limb allotransplantation. METHODS: A total of 101 male SD rats were randomly divided into seven groups and used as recipients, and 101 Wistar rats were used as donors. All SD rats were performed limb allotransplantation without using immunosuppressants in control group. In experimental groups (Groups 1-6), the recipients were immunosuppressed with various dosages of FK506, RS-61443 or FK506 + RS61443, after transplantation for 5 weeks. To evaluate the results, we observed circulation of the transplanted limb, the mean rejection time, the histologic grading of skin rejection of limb grafts and the survival time of limb grafts. RESULTS: The control group showed rejection signs (edema and erythema of the skin) after a mean time of 3.36 +/- 1.15 days, and the mean survival time of the allografts was only 7.00 +/- 0.78 days. In the groups only using FK506 or RS-61443, the survival time were prolonged to varying degrees, but rejection occurred even in the period of using drug. As dosage increased, the rejection could not be prevented and the damage to liver and kidney could be induced. In the group using FK506 in combination with RS-61443, only skin and muscle of limb allografts showed slight rejection sign, function of liver and kidney was not obviously affected, the mean survival time of limb allografts was prolonged to 58.76 +/- 6.81 days. CONCLUSIONS: A combination of FK506 and RS-61443 is a more potent immunosuppressive agent than FK506 oro RS-61443 in preventing the rejection of limb allografts, and it can obviously prolong the survival time of limb allografts.
Objective To study the relationships between expressions of somatostatin receptor subtypes（SSTR1-SSTR5） and angiogenesis in colorectal cancer. Methods The expressions of SSTR1-SSTR5, VEGF, and CD34 in the paraffin sections of colorectal cancer tissues from 127 cases were detected by the standard streptavidin-peroxidase (SP) technique. CD34 was used as a marker to account microvessel density (MVD) in colorectal cancer tissues. The relationships between the expressions of SSTR1-SSTR5 and VEGF expression, or MVD were analyzed. Results The positive expression rate of SSTR1, SSTR2, SSTR3, SSTR4, and SSTR5 was 64.6% （82/127）, 36.2% （46/127）, 18.9% （24/127）, 18.9% （24/127）, and 38.6% （49/127） in colorectal cancer tissues, meanwhile, the positive expression rate of VEGF was 63.8% （81/127） and MVD was (34.67±16.62)/HP in colorectal cancer tissues. The positive expression rate of VEGF (47.8%， 22/46) and MVD 〔(29.00±15.32)/HP〕 in colorectal cancer tissues with SSTR2 positive expression were significantly lower than those in colorectal cancer tissues with SSTR2 negative expression 〔72.8%， 59/81； (37.90±16.56)/HP〕, Plt;0.05. There were no relationships between SSTR1, SSTR3, SSTR4, and SSTR5 expression and VEGF expression or MVD （Pgt;0.05）. Conclusion The positive expression of SSTR2 is related with angiogenesis in colorectal cancer tissues.
【Abstract】ObjectiveTo construct eukaryotic expression vector pSecTag2/HygroB-CD59 of human CD59 and transfect NIH3T3 cells after encapsulated by chitosan. MethodsThe human CD59 fragments were obtained by PCR form CD59-pGEM-T Easy Vector, cloned into the eukaryotic expression vector pSecTag2/HygroB, identified by restriction endonuclease’s digestion and DNA sequencing. After the particles of pSecTag2/HygroB-CD59 were encapsulated by chitosan, the NIH3T3 cells were transfected by chitosanCD59 nanoparticles and detected CD59 expression by immunohistochemistry stain. ResultsThe CD59 fragment was 312 bp. Its sequence was as same as CD59 cDNA in Genbank. After having been transfected by chitosan-CD59 nanoparticles in 24 hours, the 3T3 cells showed diffusely positive in the cytoplasms by anti-CD59 immunohistochemistry. ConclusionThe eukaryotic expression vector of human CD59 is constructed and transfected to NIH3T3 cells after encapsulated by chitosan. It will be very helpful for further study on transgenic livers.
【Abstract】Objective To demonstrate the role of p16 protein and Rb protein in the formation and progression and their relationship in thyroid carcinoma. Methods p16 and Rb from 46 patients with thyroid cancer were detected by SP immunohistochemistry. Results In thyroid carcinoma,the p16 positive rate was decreased with the decline of differentiation. There was an inverse correlation between the rates of p16 positive expression and involvement of lymph node,clinical stage and prognosis index.The Rb protein was not present in any cases as a nucleus staining. Conclusion The p16 gene is likely to play an important role in the genesis and malignant progression of thyroid carcinoma,while the Rb gene is not .
The spleen cells,from the Liwis rats on the 14th day after immunization with interphotoreceptor retinoid-binding protein(IRBP),were cultured alone or with IRBP for 48 hours.As high as 3times;10 7cells were intraperitoneously transfered to naive rats.The cells stimulated by IRBP in vitro were able to transfer both EAU,EAP and specific immune reactions,contrary to those cultured aloe which transfer neither EAU,EAP nor specific immune reactions.It is highly suggested that EAU is predominantly T cell-mediated and that cells incubation with IRBP prior to transfer is indispensable for induction of EAU in naive recipients. （Chin J Ocul Fundus Dis,1993,9:210-213）