This study is to investigate the effect of local phVEGF(165) injection on sciatic nerve regeneration in the rats and to search for a new way in the further treatment of peripheral nerve injuries. Forty-five adult male Wistar rats received a neurotomy to bilateral sciatic nerves, which were subsequently reconnected with 10/0 epineurial nylon sutures. The injured segments was locally injected with normal saline (group A), or 25 microg of phVEGF(165) (group B) or 50 microg phVEGF(165) (group C). Nerve conduction and regeneration were evaluated in terms of the histological changes, weight of gastrocnemius muscles, electrophysiology and morphometric results. Our study demonstrated that rats of group C showed the best results in terms of nerve regeneration, followed by group B and group A. Our findings suggested that local injection of phVEGF165 can facilitate nerve regeneration and promote functional recovery in a dose-dependent manner.

BACKGROUND:Vascular endothelial growth factors (VEGF) can promote the division of endothelial cells and accelerate the growth of newborn vessels, whereas the expression and distribution of VEGF receptors (VEGFR) in spinal cord should be observed.OBJECTIVE: To observe the expression and distribution of VEGFR-1 and VEGFR-2 in rat spinal cord.DESIGN: A randomized controlled observation.SETTING: Department of Orthopaedic Surgery, the First Affiliated Hospital of Dalian Medical University; Department of Hand Surgery, Union Hospital affiliated to Tongji Medical College, Huazhong University of Science and Technology.MATERIALS: Ten adult male Wistar rats of clean degree, weighing 180-200 g, were provided by the animal experimental center of Tongji Medical College, Huazhong University of Science and Technology. Immunohistochemical primary antibody was purchased from Santa Cruz Company; the second and third antibodies from Beijing Zhongshan Biotechnology Co., Ltd. Reverse transcription-polymerase chain reaction (RT-PCR) kit was the product of Promega,Trizol reagents were purchased from Invitrogen Company, and the VEGFR-1 and VEGFR-2 primers were designed by Beijing Aoke Company.METHODS: The experiment was carried out in the laboratory of Department of Hand Surgery of Wuhan Union Hospital from March to June in 2004. ① Detection of VEGFR expression in spinal cord anterior horn: The rats were anesthetized by 100 g/L chloral hydrate, spinal cord of lumbar 4-6 (L4-6) was fixed in fixation solution at 4 ℃ for overnight, then routine dehydration, hyalinization and paraffin embedding were performed, and serial sections of about 5 μm were prepared for observing the VEGFR expressions using immuniohistochemical staining. ② Detection of VEGFR mRNA expression in spinal cord: Five rats were selected, L4-6 spinal cord (50 mg) was removed and centrifugated, then the content of total RNA was determined with ultraviolet spectrophotometer. The synthetized cDNA was amplified with PCR, and the PCR products (10 μL) were treated with 20 g/L agarose gel electrophoresis, and stained with 0.1 mg/L ethidium bromide, the results were observed and recorded under ultraviolet lamp and photographed. The products were scanned and quantified with gel imaging analytical system to record the gray value of each band, the gray value of β-actin band was taken as 1,and those of the other objective fragments were compared with it to record the gray value ratio and analyze the expressions of the objective fragments.MAIN OUTCOMEMEASURES: ① Expression and distribution of VEGFR-1 and VEGFR-2 in rat spinal cord anterior horn;② Results of VEGFR mRNA expression in spinal cord.RESULTS: ① Both VEGFR-1 and VEGFR-2 were expressed in the microvessels of normal rat spinal cord tissue.Besides, VEGFR-2 mainly expressed in motor neurons, glial cells and the nerve fibers in surrounding white matter. ②The results of gel imaging analytical system showed that the VEGFR-2 content in normal spinal cord was obviously higher than VEGFR-1 (0.874±0.222, 0.486±0.181, P ＜ 0.05).CONCLUSION: VEGF promote the formation of microvessels through the combined effects of VEGFR-1 and VEGFR-2,and it plays the neurotrophic and neuroprotective role through VEGFR-2.

Objective To establish an experimental model of HCV C-HBV X coexpression protein and explore its effect on tolemerase activity. Methods The HBV X gene was recovered by enzyme digestion, cloned into PBK-CMV and PBK-HCV C, and the recombinant plasmids PBK-X and PBK-X-C were obstained. The plasmids PBK-CMV, PBK-X, PBK-HCV C and PBK-X-C were transfected into HepG2 cells with liposome. After selected with G418, positive colonies were obtained. The reverse transcription PCR and Western blotting were used to detect HBV X and HCV core protein expression and PCR-ELISA for tolemerase activity. Results The recombinant plasmid PBK-X-C could express HBV X and HCV core protein efficiently. The telomerase activity of the cells coexpressed HCV C-HBV X protein was higher than that of cells expessed HBV X, HCV C and vector only. Conclusion HBV X-HCV C coexpression protein can increase the telomerase activity of HepG2 cells, which suggests that HBV and HCV can cooperate with carcinogenesis.

Objective To evaluate the imaging characteristics of 18 F-FDG PET/CT in patients with Castleman's disease (CD).Methods Twelve patients (male 7,female 5,mean age:(51.2±19.3)years) with pathologically confirmed CD and 18F-FDG PET/CT were retrospectively enrolled.A lesion with SUVmax greater than that of normal liver tissue was defined as positive.Lesion size (short diameter) was measured.Correlation between size and SUVmax was analyzed by Pearson correlation analysis.SUVmax of different clinical and pathological types was compared using Mann-Whitney rank sum test.Results Among 12patients,7 patients had localized CD (LCD) involving a single group of lymph nodes and 5 patients had multicentric CD (MCD) involving more than one group of lymph nodes with some having lung and spleen infiltration.A total of 129 positive lesions were found (7 of LCD,122 of MCD) and the average SUVmax was 4.20±1.84 (range:2.50 to 10.70).There was no significant correlation between SUVmax and lesion size (r =0.189,P＞0.05).There was no significant difference in SUVmax between LCD and MCD (4.23±1.77 vs 4.19±1.86; Z=-0.108,P＞0.05) ; but there was significant difference in SUVmax between the patients with and without clinical manifestations (4.56±2.06 vs 3.41±0.87; Z=-2.443,P＜0.05).No significant difference was found between SUVmax of hyaline vascular CD and plasma cell CD (3.63±0.89 vs 4.26±1.91; Z=-0.519,P＞0.05).Conclusions CD shows primarily lymph node involvement with increased 18F-FDG uptake.However,the degree of FDG uptake does not correlate with clinical presentation or pathological types.

Objective To analyze a large number of Cumulative Paternity Index (CPI) data in Single-parentage identification with stochastic simulation method. Methods Using the software in Identifiler, PP18D, AGCU EX20, PP21, AGCU 21+1 system, 1 million groups of STR genotyping of parent-child were analyzed. The average rate of very low CPI (RVLCPI), the median of PI in every loci (MPI), and the average PI of 39 STR loci (PIsolo) were counted out. And calculation formula of the number of STR loci that need more testing (N) was derived. Results RVLCPI in Identiifler, PP18D, AGCU EX20, PP21, AGCU 21+1 system were 24.9%, 6.5%, 1.4%, 0.7%, 0.000 1%. On the premise of inclusion relations between every kits, the number of autosome STR loci is inversely proportional to RVLCPI. PIsolo was 1.843 2. There was a signiifcant positive correlation between MPI and PEduo (r=0.956, P<0.001). The formula of the number of STR loci that need more testing was N=?log1.843 2(10 000/P)?. Conclusion The result and the formula in this paper are effcient in single-parentage identiifcation.

The PBL was adopted by the author in training medic in the department of digestion.The method has shown that it can improve the capability of independent study,spirit of team cooperation,clinical practice ability and improve comprehensive qualities.In the meanwhile,it can improve the tutor's all-around caliber.To guarantee the teaching effect,the tutor should especially comprehend the theory and skills of PBL,to design masterly clinical questions,to ensure the practice time and assistant facilities thoroughly.

Objective:To investigate the value of quantitative electroencephalography (qEEG) in the evaluation of thrombolytic efficacy in acute cerebral infarction.Methods:A prospective cohort study was conducted. Ninety-four patients with acute cerebral infarction who received intravenous thrombolysis admitted to the department of emergency of Qinhuangdao First Hospital from October 2019 to September 2020 were enrolled. The relative energy values of δ, θ, α and β waves in qEEG before and 2 hours, 24 hours and 7 days after intravenous recombinant tissue plasminogen activator (rt-PA) thrombolysis were dynamically monitored, and the power ratio index [DTABR, DTABR = (δ+θ)/(α+β)] was calculated. The National Institutes of Health stroke scale (NIHSS) score was also recorded. The reduction of NIHSS score ≥ 3 or the disappearance of neurological symptoms were regarded as effective thrombolytic therapy. The changes of DTABR before and after thrombolysis in patients with effective and ineffective thrombolysis were analyzed, and the correlation between DTABR and NIHSS score was analyzed by Pearson method.Results:A total of 94 patients were enrolled, including 64 males and 30 females. The average age was (61.71±10.11) years from 36 to 89 years old. Thrombolysis was effective in 57 cases and ineffective in 37 cases. Compared with before thrombolysis, DTABR of the effective group was significantly decreased at 2 hours, 24 hours and 7 days after thrombolysis (left cerebral infarction: 1.87±1.45, 1.59±0.88, 1.58±0.90 vs. 3.82±2.60; right cerebral infarction: 1.55±0.57, 1.41±0.50, 1.35±0.44 vs. 3.20±1.63, all P < 0.05). DTABR did not change or increase significantly at 2 hours, 24 hours and 7 days after thrombolysis compared with before thrombolysis (left cerebral infarction: 3.56±2.57, 3.48±2.19, 3.54±2.50 vs. 3.11±1.62; right cerebral infarction: 5.29±3.93, 5.33±3.94, 5.19±4.52 vs. 4.73±2.43, all P > 0.05). Pearson correlation analysis showed a significant positive correlation between DTABR and NIHSS score in patients with acute cerebral infarction (r = 0.691, P < 0.01).Conclusion:The quantitative index of qEEG, DTABR, can accurately and quickly monitor the process of thrombolysis in acute cerebral infarction, and can effectively evaluate the effect of thrombolysis in patients.

Objective To explore effects of ephedrine on epinephrine (EPI) and estradiol( E2)concentration in blood, histological structures and activity of superoxide dismutase (SOD) and maleic dialdehyde (MDA) content in the ovary of female mice.Methods Pregnant female mice in the experimental group were treated with ephedrine (2g/L,4g/L, 6g/L), and the mice in the control group were treated with saline by intraperitoneal injection .Using ELISA method to detect concentration changes of EPI and E 2 in plasma, the changes in the enzymatic activity of SOD and MDA content were analyzed by colorimetry .The ovarian weight was measured , histological structures in ovary were observed by microscopy and the number of ovarian follicles were counted .Results EPI concentration in plasma of female mice increased , and the E2 concentration decreased dose-dependently in the experimental group .The activities of SOD were lower , and MDA content significantly increased compared to the control .The ovary weight of experimental groups was lower than the control group.The numbers of primary follicle , secondary follicle and atretic follicle increased and corpus luteum decreased in the experimental groups .There were pyknotic ovarian tissues , including oocyte ateophy , degradation granulose cells , and karyopyknotic granulose lutein cells in the experimental groups .Conclusion Ephedrine has a great effect on the ovarian histological structure and ovarian function of female mice , which may be correlated with the low activities of SOD .

Objective:To investigate the antibacterial effect of different self-etching adhesive systems against Streptococcus mutans (S.mutans).Methods:Six reagents ClearfilTM SE Bond primer (SP), ClearfilTM SE Bond adhesive (SA),ClearfilTM Protect Bond primer (PP),which contained antibacterial monomer methacryloyloxydodecylpyridinium bromide (MDPB),ClearfilTM Protect Bond adhesive (PA), positive control chlorhexidine acetate [CHX,1% (mass fraction )],and negative control phosphate buffer solution (PBS)were selected.They were mixed with S.mutans for 30 s respectively,then colony-forming units (CFU)were counted after incubated for 48 h on brain heart infusion (BHI)agar medium. The 6 reagents were applied to the sterile paper discs,and distributed onto the BHI agar medium with S. mutans and incubated for 24 h,then the inhibition zones were observed.CHX,PBS,PP,and SP were added on the dentin with artificial caries induced by S.mutans and kept for 30 s,then confocal laser scanning microscope (CLSM)was used to observe the live and dead bacteria after staining.The ratio of live to dead bacteria was calculated.PP+PA and SP+SA were applied on the dentin according to the manual and light cured.S.mutans were incubated on the samples for 2 h,ultrasonically treated and in-cubated on BHI agar medium for 48 h,then CFU was counted.The data were analyzed by non-parametric analysis and one-way ANOVA.Results:Compared with PBS,the PP,SP,PA,SA and CHX showed the antibacterial effect on free S.mutans (P<0.05 );SP and PP showed stronger antibacterial effect than PA,SA and CHX (P<0.05).CHX,SP and PP presented inhibition zones,while PBS,SA and PA did not.Compared with PBS,the CHX,SP and PP could lower the ratio of the live to dead bacteria significantly (P<0.05).Cured self-etching adhesive systems did not show any antibacterial effect on the free S.mutans.Conclusion:The primer of self-etching adhesives ClearfilTM SE Bond and ClearfilTM Pro-tect Bond showed significant antibacterial effect on free and attached S.mutans.The adhesive only showed antibacterial effect on free S.mutans before light-cured polymerization.After being cured,the self-etching adhesive systems did not show antibacterial effect anymore.

Objective:To investigate the effect of thermal conductivity on the apical sealing ability of different dental gutta-percha cones during the warm vertical condensation obturation.Methods:Four kinds of dental gutta-percha cones were used in this study:Bio-GP points (BP,B&L,Korea),large-tapered gutta-percha (DP,DENTSPLY,America),PROTAPER Universal gutta-percha points (DPP,DENTSPLY,America) and mtwo gutta-percha points (VP,VDW,Germany).Volume differences method was used to determine the main components and the thermal conductivity determinator was used to measure the thermal conductivity of these dental gutta-percha cones.Furthermore,20 cones randomly selected from each kind of dental gutta-percha cones.And 10 cones of each dental gutta-percha cones,which were cut out the part of 4 mm in length from the apical end,were heated (200 ℃) from the upper end without compression,and the temperature of the gutta perchacones surface was monitored in time by the infrared thermal imager during the whole heating process.In addition,the rest of the 10 cones of each dental gutta-percha cones were used to obturate the root canal in the transparent root canal resin model using warm vertical condensation technique.The cross-sectional surface was observed by stereomicroscope (× 40) at 1 mm and 3 mm from the working length and the gutta-percha obturation area proportion was measured and analyzed.The data were analyzed by one-way ANOVA.Results:The proportion of inorganic fillers (80.90％ ± 1.14 ％) (P ＜ 0.05) and the thermal conductivity (2.247 ± 0.002)of DP was siguificantly higher than BP (79.28％ ± 3.88％,1.179 ± 0.003),DPP (68.46％ 5.09％,0.604 ±0.001),VP (78.86％ ± 1.87％,1.150 ±0.001) (P ＜0.05).During the thermal obturation without compression at the setting temperature (200 ℃),DP could achieve 65 ℃ beyond 1 mm from the heating point,and BP,DPP and VP only reached 65 ℃ within 1 mm.After warm vertical condensation obturation,all the groups showed increased gutta-percha obturation area proportion.At the position of WL-3,DP (96.89％ ±0.03％) showed significantly higher proportion of gutta-percha obturation area than BP (95.47％ ±0.06％),DPP (95.21％ ±0.03％) and VP (95.15％ ±0.03％) (P ＜ 0.05).Conclusion:DP contains more inorganic fillers,possesses higher thermal conductivity,and leads a better apical sealing ability than BP,DPP and VP at the position of WL-3 during warm vertical condensation obturation.