Objective Antimicrobial peptides are the focus of recent research in oral microbiology .This study aimed to eval-uate the activity of a novel antimicrobial peptide pm 11 against oral microorganisms and its action mechanisms . Methods We ana-lyzed the effect of pm11 on oral microorganisms and determined its antimicrobial activity in the saliva environment by measuring its min -imal inhibitory concentration (MIC), minimal bactericide concentration (MBC), and bactericidal kinetics.We observed its bacteri-cidal activity on the biofilms of streptococcus mutans by confocal laser scanning microscopy (CLSM) and the structural changes in the bacterial membrane by scanning electron microscopy (SEM). Results The antimicrobial activity of pm11 varied greatly against dif-ferent oral microorganisms , with its MIC values ranging from 2 μg/mL to 256 μg/mL and its MBC values from 2 μg/mL to >256μg/mL.The bactericidal kinetics showed a decreasing survival rate of bacteria with the lengthening of the intervention time .The inhib-itory-zone diameters exhibited no significant indifference between the water solution and the sterile saliva solution .CLSM revealed an increased number of dead bacteria in the pm 11-treated biofilms , while SEM manifested obvious changes in the shape of the bacteria membrane treated with pm11. Conclusion Our findings suggest that pm11 has a broad spectrum of antimicrobial activities on oral mi-croorganisms and a potential value of clinical application .

Cell Physiological Phenomena ; Humans ; Vocal Cords ; cytology ; physiology

Objective Streptococcus sanguis is a possible candidate bacterium for the caries replacement therapy, which has no advantages in the acidic environment.The aim of the study was to construct acid-resistant strains of Streptococcus sanguis, determine its acid tolerance, and explore the mechanism of its antagonism against Sterptococcus mutans.Methods By gradually reducing the pH value of the medium, we constructed acid-resistant strains of Streptococcus sanguis, observed their growth and measured their acid tolerance according to their survival rate against lethal pH.We evaluated the competitive relationship between Streptococcus sanguis and Streptococcus mutans by plate experiment and detected the changes of related acid resistance genes by real-time quantitative PCR.Results The growth of Streptococcus sanguis and its acid-resistant strains were limited by the pH value, and that of Streptococcus sanguis was better in either acidic or normal environment.The lethal pH value of Streptococcus sanguis was 3.6, that of its acid-resistant strains was 2.3, and the survival rate of the acid-resistant strains was 66.59% in the pH 3.6 environment.In comparison, the lethal pH value of Streptococcus mutans was 2.5, that of its acid-resistant strains was 2.1, and the survival rate of the acid-resistant strains was 2.55% in the pH 2.5 environment.In the presence of chloramphenicol, the acid-resistant strains could not survive in the original lethal pH.In the sub-lethal pH environment, the expressions of the acid resistance-related genes Groel and Dnak in the acid-resistant strains were significantly up-regulated as compared with those in the original Streptococcus sanguis (P<0.05).Conclusion Streptococcus sanguis has an acid adaptability and can enhance acid resistance in the sub-lethal pH environment.Acid-resistant Streptococcus sanguis in the replacement therapy may provide some new ideas for the treatment of dental caries.

Objective To assess the outcome of liver transplantation in patients over sixty years of age,in order to attempt to expand the indications of liver transplantation. Methods From August,2000 to January,2002, the clinical data of 36 patients who underwent liver transplantation in our department were analysed retrospectively. Of the 36 cases, the data (operating time, the length of hospitalization, rejection rate and ICU stay days after operation) of 5 patients whose age were ≥60 years (elderly group) and the data of 31 patients whose age were under 60 years (

Objective To evaluate the effects of different selection criteria on the prognosis of hepatocellular carcinoma(HCC)patients undergoing liver transplantation(LT)and to evaluate a new criterion.Methods A retrospective analysis was performed on 81 consecutive patients with HCC who underwent LT.The survival rates of the patients who met different criteria such as Milan.UCSF(University of California San Francisco UCSF).and Pittsburgh(Pitt)modified TNM criteria were calculated by KaplanMeier method,and the value of different criteria was evaluated.The Long-Rank test and COX proportional hazards regression model were performed to analyze the prognostic factors.the model of criteria was established according the most important prognostic factors.Using the Kaplan-Meier method,the suitable cut-offs of every variable ifl the model were found by comparing the survival and the number of the patients who met the cut-off,and considering the significant difference between the patients who met and exceed the cut-off at the same time.Resuits The 1,2,3-year accumulative survival rates of the 19 patients who met Milan criteria were 87.7%,87.7%,and 52.6%respectively:the 1,2,3-year disease free survival rates of them were 88.9%,72.7%,and 72.7%respectively.The 1,2.3-year accumulative survival rates of the 26 patients who met UCSF criteria were 87.2%,80.5%,and 55.2%respectively;the 1,2,3-year disease free survival rates of them were 84.1%,68.4%,and 68.4%respectively.With our new expanded criterion as of solitary tumor≤8 cm in diameter.or no more than 3 tumors,with the largest≤6 am,and a total tumor diameter≤10 cm.there was no significant difierence in 1,2,3-year sunrival rates and disease free survival rates(89.0%,81.8%,71.8%,and 81.9%,72.4%,72.4%.)as compared with Milan or UCSF criteria.but with this new criterion more patients(a=41)would be eligible for transplantation with a comparable long term survival.and the difference of the accumulative survival rates and disease free survival rates of the patients who met and exceed the new criteria was significant(P＜0.05).Conclusion The new indication is acceptable because the criteria does not adversely impact survival.

Objective To summarize the experience in the diagnosis and treatment of elastofibroma dorsi,focusing on the clinical features,the specific radiological characteristics,and the typical pathological alterations.Methods Clinical data of 10 cases of pathologically confirmed elastofibroma dorsi from January 1997 to April 2008 were retrospectively reviewed.Results Most patients were female(8/10)in this series.All the lesions were located within the muscles in the subscapular region.There were 13 lesions in 10 cases(3 cases with bilateral involvement).Seven patients complained of pain and feeling of foreign body,and three were asymptomatic.The size of the masses was between 4 centimeters to 12 centimeters,averaging at(7.46 ±2.70)centimeters.Except for the early 3 cases,accurate diagnosis was made in all the other 7 cases before the histological exams solely based on the physical examination and imaging findings.Marginal excision was done for all the cases under general anesthesia.Fluid accumulation,as the only kind of complication was found in 3 cases which was resolved by repeated paracentesis.No recurrence was found during the follow-up period(4 months to 125 months,median 11 months).Conclusion Elastofibroma dorsi is a rare,pseudotumoral lesion usually found in elderly women.It is a very special type of soft tissue tumors that its diagnosis can usually be made solely on the basis of unique imaging characteristics and physical examination before the histological exam.Surgical marginal excision is the choice of treatment with good short-term and long-term results.

Objective To summarize the initial experience in application of mesohepatectomy for the treatment of central liver tumors while focusing on its indication, short-term and long-term prognosis and especially outlining its technical details. Methods The clinical data of 3 patients receiving mesohepatectomy from December 2007 to March 2009 in our hospital were retrospectively analyzed.The imaging characteristics were summarized to convey the indication details. The technique details of the operation were outlined so as to reduce blood loss or other complications during and after the operation. The post-operative course and follow-up data were also collected and analyzed. Results Two patients suffered from primary hepatocellular carcinoma with liver cirrhosis and the other from giant hemangioma. The tumors were located in Couinaud yegment Ⅳ and/or Ⅷ. The average blood loss and operative duration were 800 ml and 7 h, respectively. Blood liver function tests returned to normal within 7 days postoperatively and the patients were discharged after that. No complications occurred. The follow-up for 7-15 months showed that there was no recurrence. Conclusion Mesohepatectomy is the principal choice of treatment for centrally located liver tumors. For the safety and avoidance of complications, the doctor should abide by the concept of segment-oriented hepatectomy and apply the updated techniques such as CUSA (Cavitron ultrasonic surgical aspirator). For patients with compromised liver function, mesohepatectomy might be superior to extended bepatectomy. Thus, the application of mesohepatectomy should be expanded. Meanwhile, further investigation is needed for its full evaluation.

Objective To evaluate a new system,Vitek 2 Compact,for antimicrobial susceptibility testing(AST)of gram-negative and gram-positive bacteria.Methods Eighty-nine clinical isolates of Peking Union Medical College Hospital,including 48 gram-negative strains and 41 gram-positive strains,and 66 reference strains kept in our laboratory,including 41 gram-negative strains and 25 gram-positive strains, were studied.The antimicrobial susceptibility of these strains were tested by Vitek 2 Compact with AST- GN09(for gram-negative bacteria),AST-P536(for Staphylococci),AST-P534(for Enterococci and S.agalactiae),and AST-P533(for S.pneumoniae)susceptibility cards.The Etest was used as the reference method for comparision.Thirty-two ESBL-producing strains assessed with the confirmatory tests for ESBLs of CLSI(16 strains of them had been confirmed by PCR amplified and sequencing)were detected for ESBLs by Vitek 2 Compact.Results According to the breakpoints of Clinical and Laboratory Standards Institute (CLSI),for the 1 626 microorganism-antibiotic combinations,Vitek 2 Compact gave 90.83% strains with category agreement(CA),4.91% strains with very major errors(VME),2.09% strains with major errors (ME),6.40% minor errors(MIE).The AST for more than 90% of Enterobacteriaceae,nonfermenting bacteria,micrococci and streptococci were completed within 11h,13h,11h and 12h,respectively.The ESBLs tests for thirty-two strains by V-itek 2 Compact are all positive.Conclusions Vitek 2 Compact system can give rapid,reliable and reproducible result with high sensitivity and specificity in assessment of antimicrobial susceptibility testing for clinically relevant gram-negative and gram-positive bacteria,and would become a powerful tool in clinical microbiology laboratory.

A separation technology of catalpol from Rehmannia with macroporpus adsorbent resins was investigated. The content of catalpol in the extract was determined by high performance liquid chromatography (HPLC). Nine different kinds of macroporous adsorbent resins were studied on the static capacity of adsorption and desorption, and D101 resin was best for the separation of the extraction solution of Rehmannia. The results showed that D101 resin had the highest static adsorption capacity of 69.2mg/g dry resin and its isotherm curve can be well described by Langmuir and Freudlich equation. The 5% ethanol elution on removal of the solvent under reduced pressure provided a brown powder, which was subjected to an open column chromatography on silica gel eluted with a CHCl3–MeOH gradient. The fraction eluted with CHCl3-MeOH (8∶2) was identified as catalpol and the purity of the compound was more than 90% purity by HPLC analysis. The yield of this separation technology was 6%.

Objective To observe the changes in hypersplenism after orthotopic liver transplantation(OLT) and investigate the effect of OLT on hypersplenism. Methods Based on the clinical data of 14 eligible OLT patients operated on in our hospital during two and a half years, an analysis of the pre operative values of the thickness of the spleen, blood WBC and PLT count was made,and the postoperative pattern of changes of portal flow velocity was observed. Results Blood WBC and PLT count returned to normal 1 month after the operation, and the thickness of spleen reduced about 17.0% in the first month , but had no additional change at 1 year later. Portal flow velocity increased significantly 1 month after operation , then decreased slowly in the first year. Portal flow velocity , blood WBC and PLT count were all significantly related to the thickness of the spleen. Conclusions The high velocity of portal flow after OLT was mostly attributed to increased flow from the splenic vein; the main cause of the decrease in the level of blood WBC and PLT in hypersplenism before operation is augmentation of splenic volume; the recuperation of hypersplenism after OLT relies on the extent of reversion of splenic volume. It is not necessary to perform splenectomy in patients with hypersplenism when they receive OLT.