Objective To investigate the feasibility of labeling iris pigment epithelial(IPE)cells of rabbits with 5-(and 6-)carboxyfluorescein diacetate succinimidyl ester(CFSE). Methods Enzyme-assisted microdissection was used to isolate the cultured rabbit′s IPE cells.The third or forth subcultured IPE cells were incubated with 2.5,5,10,20,and 40 ?mol/L of CFSE for 1,5,and10min respectively.The fluorescence intensity was detected by flow cytometry,and the leakage of CFSE and its dyeing were observed by fluorescence antibody labeling. Results Incubation with 20 ?mol/L CFSE under 37℃for1minute was the most optimal condition for IPE cells labeling.The coloration of IPE cells stained by CFSE lasted 4 weeks.There was no leakage of dye from labeled rabbit IPE cells to non-labeled human IPE cells in mixed culture process. Conclusion With the advantages of high rate of dyeing,long time of tracing,safety and convenience,CFSE can be used as a new method to label the rabbit′s IPE cells.

Forty-five healthy male dogs were wounded with high or middle-velocity steel ball on the lower part of the face.and the findings were as follows:(1)Craniocerebral injuries concomitant with maxillofacial gunshot wounds were charcterized by brain contusion in the entry side of the temporal lobe and extradural hemorrhage in the entry side of the middle cranial fossa,and their highest incidence and severity were found in those cases with mandible fracture due to high-velocity missiles.(2)The larger the amount of the absorbed energy from the bullet,the higher the incidence and severity of the craniocerebral injury.(3)The incidence and severity of the craniocerebral injury were positively correlated to the value of vibrational acceleration measured on the pareital bones,which suggests that vibrational acceleration plays an important role in the precipitation of craniocerebral injury secondary to maxillofacial gunshot wounds.

To explore the roles of astrocytes in the epileptogenesis, astrocytes and neurons were isolated, purified and cultured in vitro from cerebral cortex of rats. The astrocytes were activated by ciliary neurotrophic factor (CNTF) and astrocytic conditioned medium (ACM) was collected to treat neurons for 4, 8 and 12 h. By using Western blot, the expression of calmodulin dependent protein kinase II (CaMK II), inducible nitric oxide synthase (iNOS) and adenylate cyclase (AC) was detected in neurons. The results showed that the expression of CaMK II, iNOS and AC was increased significantly in the neurons treated with ACM from 4 h to 12 h (P<0.05), and that of iNOS and AC peaked at 8 h and 12 h respectively. It was suggested that there might be some epileptogenic factors in the ACM and such signal pathways as NOS-NO-cGMP, Ca2+/CaM-CaMK II and AC-cAMP-PKA might take part in the signal transduction of epileptogenesis.

Objective To localize and characterize the plasmid protein pORF5 in the Chlamydia trachomatis(Ct) infected cells. Methods The open reading frame encoding for pORF5 protein from the Ct plasmid was amplified and cloned into the pGEX-6p vector. The recombinant plasmid pGEX-pORF5 was transformed into XL1-blue E. coli to express fusion protein with the glutathione-s-transferase (GST). After purified with Glutathione Sepharose 4B beads, the pORF5 fusion protein was used to immunize mice to make monoclonal and polyclonal antibody. The antibodies were used to localize the endogenous pORF5 protein and detect the expression pattern in Chlamydia-infected cells using an indirect immunofluorescence assay (IFA). At the same time, ELISA was used to determine whether pORF5 plasmid protein was expressed and immunogenic during Ct infection in humans. Results pORF5 was detected a dominant signal in the cytosol of the Chlamydia-infected cells with a pattern similar to that of anti-CPAF. pORF5 also appeared in the RBs and EBs in small quantity. Athough pattern was similarly, pORF5 did not overlap with CPAF. pORF5 protein was strongly recognized antiserum in an ELISA. Conclusion The pORF5 plasmid protein was identified as a secreted protein with good immunogenicity, pORF5 gene was to express the endogenous target protein during human infection.

Objective To construct the recombinant plasmid containing the major outer membrane protein(MOMP) gene of Chlamydia trachomatis and expres s MOMP protein in E.coli BL21. Methods The MOMP gene was amplified by polymera se chain reaction from the genome of Chlamydia trachomatis serovar D. The amplif ied fragment was directly inserted into pUCm-T vector and verified by DNA sequen cing. MOMP gene was then subcloned into the prokaryotic expression vector pET-22 b(+). The recombinant protein of MOMP was purified by Ni-NTA affinity chromatogr aphy and identified by SDS-PAGE and Western blot. Results The MOMP gene, which is about 1 200 bp, was successfully amplified and cloned. The DNA sequence of t he cloned MOMP gene was the same as that published by the GenBank. SDS-PAGE anal ysis showed that the relative molecular weight of this fusion protein was about 47 kDa which was consistent with the theoretically predicted value, and the spec ificity of this recombinant protein was confirmed by Western blot. Conclusions The MOMP gene of Chlamydia trachomatis was successfully cloned and expressed in the prokaryotic expression system, which may lay the foundation for the developm ent of Chlamydia trachomatis vaccine.

Quality is the lifeline of graduate education and the tutor team plays an important role in postgraduate training. To control the selection of tutors strictly, to implement the combination of openness and stability in tutor team, and to carry out academic exchanges actively are the keys to construct an excellent tutors staff and to ensure the quality of graduate student training.

BACKGROUND: There have been reports about the cochlea injury after high-velocity projectile wounding. The effect on ultrastructure of cochlea after blast was still unclear.OBJECTIVE: To investigate ultrastructural changes of cochlea and cochlear nerve after maxillofacial blast wound.DESIGN:A randomized controlled observational trail with dogs as subjects.SETTING: Otolaryngeal Department and Maxillofacial Surgery Laboratory of the Third Military Medical University of Chinese PLA.MATERIALS: The study was conducted from August 1995 through July 1997. The animal model in maxillofacial blast wound was established in Animal Center of Xinqiao Hospital of the Third Military Medical University of Chinese PLA. Specimens were treated in Maxillofacial Laboratory and observed in Electron Microscope Laboratory. Totally 15 dogs of either sex (weighting 9. 5 - 13.5 kg, mean 11.3 kg ) were randomly divided into three groups with 5 in each group. Two groups served as trauma groups 1 and 2 and the other group as control.METHODS: The maxillary and mandibular regions of 10 dogs in trauma groups were wounded by model 8 cardboard-shelled detonators to establish animal model of maxillofacial blast wound. At the 1st and 6th hour after trauma the wounds were examined and specimens of cochlea and cochlear nerve were dissected out for electron microscopic observation to study the ultrastructural changes. The specimens in the control group were treated the same way as those in the trauma groups except for blast injury.RESULTS: After wounded, the cochlea and cochlear nerve in the early period manifested cilia disorder, edema of the nerve and mitochondrial degeneration. At the 6th hour after trauma there were extensive degeneration in cochlea and cochlear nerve, cilia fallen off hair cells and dissolution of the structures in nerve sheath.CONCLUSION: The ultrastructural changes of cochlea and cochlear nerve are severed as a result of maxillofacial blast wound, but in early period the injury is reversible. So it is very important that early cure should be emphasized in treatment.

Objective To investigate the expression ofTNF- α mRNA and cytokeratin 20(CK20)mRNA in different tissue of colonic cancer patients, and the relations between the expression and the classify,invasion, as well as Dukes stage of colonic cancer. Methods RT-PCR method was used to detect the ex-pression of TNF-α mRNA and CK20 mRNA in 30 cases of colonic cancer, included cancer tissue,para-cancer tissue and normal tissue. Results The positive rate of TNF- α mRNA expressions in cancer tissue, para-cancer tissue and normal tissue were 70.0%, 43.3% and 20.0%, and the positive rate of CK20mRNA expressions were 63.3%, 33.3% and 16.7%, there were significant difference among the three tissues(P ＜ 0.01 ). But the expression of CK20 mRNA in para-cancer tissue had no significant difference compared with normal tissue (P＞ 0.05). The expression ofTNF- α mRNA was closely correlated with that of CK20mRNA.TNF- α mRNA and CK20 mRNA showed no significant difference in expressing of colonic cancer tissue (P ＞ 0.05 ), but TNF- α was closely correlated with Duke stage and depth of tumor invasion (P ＜ 0.05 ).Conclusion The expression of TNF- α mRNA is objective indicator associated with the invasion of the colonic cancer.

To localize and characterize the hypothetical protein CT358 in the chlamydial infected cells. CT358 gene from the Chlamydia trachomatis (C. trachomatis) serovar D genome was amplified and cloned into the pGEX and pDSRedCI vectors. The recombinant plasmid pGEX-CT358 was constructed and expressed as GST fusion proteins. The GST-CT358 fusion protein was used to immunize mice to raise the antibodies, which specifically recognized CT358 without eross-reacting with other unrelated proteins. The antibodies were then used to localize the endogenous CT358 protein and determine the expression pattern in Chlamydial infected cells using an indirect immunofluorescence assay (IFA). Meanwhile, pDSRedC 1-CT358 recombinant plasmid was transfected to HeLa cells to evaluate the effect of CT358 expression on the subsequent chlamydial infection. The hypothetical protein CT358 was identified in the inclusion membrane of C. trachomatis-infected cells for the first time,and it was detected as early as 12 h after C. trachomatis infection and remained in the inclusion membrane throughout the rest of the infection cycle. Cytosolic expression of CT358 via a transgene failed to affect the subsequent ehlamydial infection. These observations together have demonstrated that CT358 is a newly identified chlamydial inclusion membrane protein, giving the potentially importance for further understanding the mechanisms of chlamydial intracellular parasitism.

Objective To evaluate the effect of dexmedetomidine on cognitive dysfunction after thoracic surgery in patients undergoing one-lung ventilation.Methods Sixty-two patients,aged 45-64 yr,of ASA physical status Ⅰ or Ⅱ,with body mass index ranged from 17.5 to 25.5 kg/m2,scheduled for elective thoracic surgery,were randomly allocated into 2 groups (n =31 each) using a random number table:dexmedetomidine group (Dex group) and control group (C group).Dexmedetomidine 0.5 μg/kg was infused for 10 min starting from the time point before induction of anesthesia,followed by continuous infusion at a rate of 0.5 μg · kg-1 · h-1 until 30 min before the end of surgery in Dex group.The equal volume of normal saline was administered instead in group C.Before induction and at 24,48 and 72 h after surgery,venous blood samples were collected for determination of levels of S-100 beta protein and neuronspecific enolase in serum by ELISA.Cognitive function was assessed by Mini-Mental State Examination at 72 h after surgery.Results The levels of S-100 beta protein and neuron-specific enolase in serum were significantly increased after surgery than before induction in the two groups.Compared to C group,the levels of S-100 beta protein and neuron-specific enolase in serum were significantly decreased after surgery,and the incidence of postoperative cognitive dysfunction was decreased in Dex group (26％ vs 6％).Conclusion Dexmedetomidine can effectively reduce the nerve damage during one-lung ventilation and significantly inhibit the development of postoperative cognitive dysfunction in patients undergoing thoracic surgery,indicating that dexmedetomidine is suitable for thoracic surgery.