AIM: To study the protective effects of dexamethasone agains t ototoxicity of aminoglycoside antibiotics in guinea pigs. METHODS: Guinea pigs were divided into five groups. Group One: gentamycin, im; Group Two: amikacin, im; Group Three: gentamycin+ dexamethasone, im; Group Four: amika cin+ dexamethasone,im; Group Five: NS, im, all for two weeks. After three weeks, all animals were examined including tympanic mucous membrane reaction, nystagmu s depression rates and cochleae morphology. RESULTS: In Group Th ree and Four, the changes of morphology were slighter than those in Group One an d Two. CONCLUSION: Dexamethasone can weaken ototoxicity of amino glycoside antibiotics.

Objective To investigate the effect of salinity and temperature on motility of Vibrio parahaemolyticus. Methods V.parahaemolyticus was inoculated on swarming or swimming agar plates containing different amounts of salinity (0.5%, 1.0%, 2.0%, and 4.0% NaCl, respectively), followed by incubation at 26 or 37℃, before the diameters of bacterial lawns were measured .Results and Conclusion The swarming motility was not affected by salinity , while the swimming motility was positively correlated with salinity .Maximum swimming occurred in 2.0% NaCl, and displayed a slight decline in salinity of 4.0%.Both swimming and swarming were affected by temperature , and the motility was signifi-cantly enhanced in 37℃vs 26℃.These results indicate that both salinity and temperature can modulate the motility of V. parahaemolyticus.

Objective To investigate the regulation of swimming motility by H-NS in Vibrio parahaemolyticus(VP). Methods VP was inoculated into the semi-solid swimming agar plate containing 1% Oxoid tryptone, 2% NaCl, 0.5%Difco Noble Agar, and 0.1% arabinose followed by incubation at 37℃ for 4.5 h before the diameters of bacterial lawns were measured.Total RNAs were extracted from the wild-type (WT) strains and the hns null mutant (Δhns), and the quantitative real-time( RT)-PCR( qRT-PCR) was carried out to calculate the transcriptional variation of flaA between WT andΔhns strains.The entire promoter DNA region of flaA was amplified and cloned into the lacZ fusion vector pHRP309 containing a promoterless lacZ gene. The recombinant lacZ reporter plasmid was transformed into WT and Δhns, respectively, to measure the β-galactosidase activities in cellular extracts using the β-galactosidase enzyme assay system. Results and Conclusion The phenotype results showed that swimming motility of VP was enhanced by H-NS.The qRT-PCR and LacZ fusion results indicated that the transcription of flaA was positively regulated by H-NS.Collectively, H-NS promotes the swimming motility of VP, at least partly, by activating the transcription of flaA.

The present paper is aimed to study the preparation and application of individual artificial bone of carbon/carbon composites. Using computer tomography images (CT), we acquired a three-dimensional image. Firstly, we described bone contour line outlined with manual and automatic method by the binary volume data. Secondly, we created 3D object surface information by marching cubes. Finally, we converted this information to non-uniform rational B-spine (NURBS) by using geomagic software. Individual artificial bone with carbon/carbon composite was prepared through the CNC Machining Center. We replaced the humeral head of the tested rabbit, and then observed the effects of implantation in neuroimaging and pathological section. Using this method, we found that the bone shape processed and bone shape replaced was consistent. After implantation, the implant and the surrounding bone tissue bound closely, and bone tissue grew well on the surface of the implant. It has laid a sound foundation of the preparation using this method for individual artificial bone of carbon/carbon composite material.
Animals ; Bone Substitutes ; chemistry ; Carbon ; chemistry ; Imaging, Three-Dimensional ; Rabbits ; Software ; Tomography, X-Ray Computed

Objective To analyze the prognostic value of thrombin generation assay(TGA)and coagulation factor testing in postoperative deep venous thrombosis(DVT)of lower extremities in elderly patients with traumatic fracture.Methods A retrospective case-control study was conducted to collect traumatic patients older than 60 years old who underwent surgery in our department from March 2019 to March 2022.The number of patients was 104.According to the ultrasonic examination of DVT 5 days after operation,the patients were divided into DVT group and non-DVT group.The differences of general demographic data,previous chronic diseases,time from trauma to operation,related indexes of TGA and TF coagulation factors(F)between the two groups were analyzed.The indexes with statistical significance were analyzed by receiver operating curve(ROC);the indexes with statistically significant differences were analyzed by Logistic regression and the prediction probability was calculated by ROC curve analysis.Results The incidence of postoperative DVT was 21.12％.Compared with the non-DVT group,the time from trauma to operation was longer in the DVT group,and the peak value under 5 pmol/L TF activation was lower(258.13±40.88 vs 209.58±30.09).F V,F Ⅷ and Fib were higher(141.25(125.38,158.18)vs 176.12(150.65,186.34),145.49(133.36,147.48)vs 165.96(153.07,180.65),3.25± 0.55 vs 3.92±0.72,respectively).The differences were statistically significant(all P＜0.01).ROC curve analysis showed that the time from trauma to operation,the peak value of 5 pmol/L TF activation,F V,FⅧ and Fib combined had more predictive value for postoperative DVT,the AUC was 0.91(P＜0.01),the sensitivity was 0.82 and the specificity 0.92.Conclusion The time from trauma to operation,the peak value of TGA under the condition of 5 pmol/L TF activation,F V,F Ⅷ and Fib have excellent prognostic value for the postoperative DVT of lower extremities in elderly patients with traumatic fracture,and the combined detection is more significative.