Objective: To study the effect of pulsed Nd:YAG laser irradiation combined with acidulated phosphate fluorid (APF) on the acid resistance of human dental enamel. Methods: Enamel samples were prepared from 192 caries-free extracted teeth. The smooth surface and pits and fissures were treated with 12 3 g/L APF for 4 minutes after 100,150 or 200 mJ pulsed Nd:YAG laser irradiation. Then the teeth were put into 12.3 g/L of artificial caries inducing solution (acid solution) for 1,5,10 or 24 h respectively. The control teeth were treated with APF only. The amount of calcium dissolved in the solution was determined with an atomic absorption spectrophotometer and the depth of artificial caries was measured with polarized microscope. Results: The amount of calcium dissolved in the acid solution was significantly less in the groups with laser treatment than that in those without laser treatment (P

Objective To determine the antibacterial activities of the alginate impression materials impregnated with carboxymethyl chitosan.Methods Carboxymethyl chitosan with different replace positions,replace degrees,relative molecular masses and deacetyl degrees were added into the dental alginate impression materials by different ratios.Their antibacterial activities were determined using a method according to the Chinese and Japanese standards for testing antibacterial efficacy of antibacterial materials.Escherichia coli ATCC 25922 and Staphylococcus aureus ATCC6538 were used in this test.Results O-carboxymethyl chitosan showed best antibacterial activity.O-carboxymethyl chitosan added into the alginate impression materials had the best antimicrobial activity on Escherichia coli and Staphylococcus aureus in the ratios of 1% and 1.4%,respectively.Its inhibitory bacteria rate could reach 99.99% along with the increase of deacetyl degree.Conclusion The alginate impression materials impregnated with carboxymethyl chitosan have a favorable antimicrobial activity.

Objective To evaluate the biocompatibility and antibacterial activities of the Ornidazole Slow-Release Membrane.Methods 1.The lower lips of 12 rats were sewed into 12 pockets and the pockets were immited with extracting solution of the ornidazole membrane, formaldehyde and normal saline respectively once per day.The specimens were examined histologically 7 days later.2.The dorsal muscles of 16 rats were implanted with the membranes or silk threads,and examined histologically 1 week and 2,4,6 weeks later respectively.3. The antibacterial activity against Streptococcus mutans and Fusobacterium nucleatum was observed on solid culture medium in vitro.Results The animal experiments showed the membranes were not irritative to the oral mucosa.It was found that the tissue reaction of the membranes was similar to that of the silk threads after implanted into dorsal muscles and the membranes had been degraded in the second week.And the membranes had effective antibacterial action against Streptococcus mutans and Fusobacterium nucleatum.Conclusion The Ornidazole Slow-Release Membrane possesses favorable biocompatibility and antibacterial activities.

Objective To compare the characteristics of remifentanil and sufentanil for tracheal intubation general anesthesia in gyneco-logical laparoscopic operation. Methods 80 patients received gynecological laparoscopic operation were randomly divided into the remifen-tanil group and the sufentanil group with 40 patients in each group, and they were performed total intravenous anesthesia with remifentanil or sufentanil respectively. Compare the changes of heart rate, mean arterial pressure in the two groups before and after induction, at the time of intubation, pneumoperitoneum, and after the operation. And differences in two groups were recorded in the recovery time, extubation time, postoperative pain in 24 hours, exhaust time and postoperative complications. Results Change trend and magnitude in heart rate, mean ar-terial pressure had no significant difference in the two groups (P>0. 05). The recovery time, extubation time in remifentanil group was shor-ter (P<0. 01), postoperative pain in 24 hours in sufentanil group was more mild (P<0. 01). Exhaust time and postoperative complications of the two groups had no significant difference (P>0. 05). Conclusion Remifentanil and sufentanil used in gynecological laparoscopic op-eration can achieve good effect. and effects of the two drugs on hemodynamics were similar. Remifentanil can recieve better effect in terms of recovery time, while sufentanil has better postoperative analgesia effect.

OBJECTIVE To investigate the antimicrobial susceptibility of Streptococcus pneumoniae isolated in Yantai and their mechanisms of resistance to macrolides.METHODS Antimicrobial susceptibility of S.pneumoniae was determined by agar dilution method.Phenotypes of macrolide-resistant S.pneumoniae were determined using double disk test with erythromycin and clindamycin disks.ermB And mefE genes were amplified by PCR.RESULTS Among 42 strains of S.pneumoniae,65.0% were intermediate to and no strain was resistant to penicillin.The resistance rates to erythromycin and clindamycin were 93.0%,respectively.Of 41 erythromycin resistantstrains,93.0% were constitutive resistant.ermB Was detected in 40 strains and mefE in 1 strain,both ermB and mefE genes were found in 9 strains.CONCLUSIONS The resistance rate of S.pneumoniae to penicillin is high in Yantai area,the resistance rates to erythromycin and clindamycin are very high.Target modification by ermB methylase is the predominant mechanism in macrolide-resistant S.pneumoniae in Yantai.

Objective To investigate the selective killing effect of MDA/IL-24 on human hepatocellular carcinoma line HepG2 in vitro and provide a theoretical basis for gene therapy of hepatocellular carcinoma.Methods The MDA-7/IL-24 gene was transfected into human hepatocullular carcinoma cell line HepG2 and normal liver cell line L02 with a replication-incompetent adenovirus vector.The mRNA and protein expression of MDA7/IL-24 in HepG2 and L02 cells was examined by RT-PCR and ELISA assay respectively.MTT assay and flow cytometry were used to study tumor cell proliferation and cell cycle in vitro.Hoechst and Annexin-V and PI staining were studied to indicate the apoptosis.Results RT-PCR confirmed that the exogenous MDA-7/IL-24 gene was expressed in HepG2 and L02 cells.The protein product was confirmed by assay of the supernatant with ELISA.MTT and apoptosis test indicated MDA-7/IL-24 induced growth suppression and cell apoptosis of the HepG2 cell in vitro but not in cell line L02,and cell cycle test revealed MDA-7/IL-24 could block HepG2 cell in G2/M but not in L02.Conclusions MDA-7/IL-24 selectively induces growth suppression and apoptosis in lines HepG2 in vitro but not in L02 cell,which indicates that adenovirus mediated MDA-7/IL-24 can be an excellent tool for gene therapy in hepatocellular carcinoma.

Aged ; Asian Continental Ancestry Group ; genetics ; China ; Female ; Humans ; Male ; Middle Aged ; Pedigree ; Vertigo ; genetics

OBJECTIVE: To analyze the clinical characters, surgical treatments and prognosis of differentiated thyroid carcinoma (DTC) with laryngeal or tracheal invasion. METHOD: Forty-six cases including 33 papillary and 13 follicular were retrospectively reviewed. Thirty-four cases with tracheal invasion received conservative resection (17), window resection (11) and sleeve resection (6). One case with subglottic invasion was performed subglottic partial laryngectomy. Eleven cases with trachea-laryngeal invasion received total laryngectomy(4), 3 shave technique and 4 preservative laryngectomy. RESULT Complications included infections and hypocalcaemia, 15 patients got permanent fistula. 5-year survival rate in cases of tracheal shave resection was 88.2%, while 63.6% in those of window resection and 83.3% in those of sleeve resection. Survival rate within 5 years of patients received preservative laryngectomy was 62. 5%. Conclusion: With meticulous preoperative examination and positive surgical treatment, both survival rate and quality of life could be improved in patients of DTC with laryngeal or tracheal invasion.
Adenocarcinoma ; Humans ; Laryngectomy ; Larynx ; pathology ; Larynx, Artificial ; Neoplasm Invasiveness ; Prognosis ; Quality of Life ; Retrospective Studies ; Survival Rate ; Thyroid Neoplasms ; pathology ; surgery ; Trachea ; pathology

Objective: To investigate the effects of cigarette smoking in different manners on acute lung injury in rats .Methods: The commercially available cigarettes with tar of 1,5, 11 mg were smoked in Canada depth smoking ( health canada method , HCM) manner , and those with tar of 11 mg were also smoked in international standard ( ISO) smoking manner .Rats were fixed and exposed to mainstream in a manner of nose-mouth exposure .After 28 days, the bronchoalveolar lavage fluids from left lung were collected for counting and classification of inflammatory cells and determination of pro -inflammatory cytokines IL-1βand TNF-α.The right lungs were subjected to histological examination and determination of myeloperoxidase ( MPO ) and superoxide dismutase (SOD) activities and glutathione , reactive oxygen species (ROS) and malondialdehyde (MDA) levels.Results:In both HCM and ISO manners , the degree of lung injury was closely related to the tar content of cigarettes , and significant decrease in the body weight of rats was observed after smoking for one week .In a HCM manner , smoking with cigarette of 11 mg tar resulted in robust infiltration of macrophages , lymphocytes and neutrophils into lungs , significant increase in IL-1βand TNF-αlevels and MPO activities , and significant decrease in GSH levels and SOD activities and increase in ROS and MDA levels ( all P <0.05 ) .Smoking with cigarette of 5 mg tar led to moderate increase in IL-1βand TNF-αlevels, and MPO activities (all P<0.05), and moderate decrease in GSH levels and SOD activities and increase of ROS and MDA levels ( all P<0.05).However, smoking with cigarette of 1 mg tar affected neither inflammatory cell infiltration nor IL-1βand TNF-αlevels.Conclusion: Cigarette smoking in nose-mouth exposure manner can induce acute lung injury in rats; and the degree of lung injury is closely related to the content of tar and other hazards in cigarettes .