Objective To evaluate the ability of restriction endonuclease analysis by pulsed field gel electrophoresis (PFGE REA) and random amplified polymorphic DNA (RAPD) analysis for molecular typing of Neisseria gonorrhoeae isolates. Methods Genomic DNA from 36 Neisseria gonorrhoeae isolates were digested with SpeI and analysed by contour clamped homogeneous electric fields electrophoresis. The 36 isolates were also characterised by RAPD analysis with arbitrary primer OPA 03. Results 12～19 DNA fragments from 5 to 600kb were obtained among the 36 isolates after PFGE REA. The 36 isolates were discriminated into 20 PFGE patterns. Amplification of Neisseria gonorrhoeae DNA with primer OPA 03 produced 15 different DNA fragments (280～1900bp), and 3～9 fragments per strain could be seen. The 36 isolates showed 18 different RAPD patterns. Strains sharing common auxotypes and antibiotic spectrum could be differentiated by PFGE REA and RAPD analysis. General agreement was found between these two techniques. Isolates from different geographic areas and even some isolates in the same area showed considerable amount of DNA polymorphism. In addition, some isolates shared common or very similar patterns were unique to a given geographic area. Conclusion It is concluded that both PFGE REA and RAPD analysis are useful, sensitive molecular techniques for differentiation of clinical isolates of Neisseria gonorrhoeae. They should be helpful in the investigation of strain origin, clonal relation among strains and spread of antibiotic resistance. Compared with PFGE REA, RAPD analysis is faster, relatively simple and more economical.

Oleanolic acid (OA) and ursolic acid (UA) are isomeric triterpenic acids and only one methyl's position is different between them.OA and UA always exist in the same plant,so it is difficult to separate them when determining contents by RP-HPLC.In this study,a very simple mobile phase for HPLC was developed to simultaneously determine UA and OA,and the factors affecting separation were also discussed.The mobile phase is methanol:water (95∶5) with flow rate 0.4mL/min.The retention time for OA and UA was 20.58 and 21.57 min,respectively,the resolution was 1.61.The average contents of OA and UA of three Loquat leaves sets were 1.4 mg/g and 5.6 mg/g,respectively.Regarding the HPLC,we found that changing mobile phase,adjusting the pH value or adding ion-pairing agent could not affect the separation between UA and OA greatly.While adjustment of the flow rate and column temperature could improve the resolution greatly.

Gonorrhea is a sexually transmitted disease caused by Neisseria gonorrhoeae,and substantially harms human health and socioeconomic development.Due to inappropriate treatment and the presence of drug resistance genes in patients,antibiotic resistance has emerged in Neisseria gonorrhoeae,such as resistance to penicillin,tetracycline,ciprofloxacin,or other antibiotics.Currently,extended-spectrum cephalosporins (ESCs) are the first-line treatment of gonococcal infection.With the wide use of ESCs,the sensitivity of Neisseria gonorrhoeae to ESCs has been decreasing gradually,and there have been reports on cases of treatment failure in clinical practice.In order to control gonorrhea and deal with drug resistance in Neisseria gonorrhoeae,combined therapy,alternative therapy and new drugs have been developed in clinic.

OBJECTIVE To investigate changes in Beijing dentists′ infection control(IC) practices in 2000 vs 2005.METHODS Data from questionaires of 647 dentists in 2000 and 592 dentists in 2005 were compared by using descriptive statistics and Person′s ?2.RESULTS Their response rates were 95.00%(2000) and 93.00%(2005).There were improvements in 2005 vs 2000 in reports of routine use of gloves(94.59% vs 73.31%);masks(56.78% vs 13.94%);and protective gown(38.87% vs 14.51%);change of gloves after each patient(93.47% vs 63.25%);vaccination for hepatitis B virus(HBV)(73.60% vs 32.66%);autoclave sterilization of dental handpieces after each patient(95.07% vs 41.24%);flushing waterlines after each use(70.78% vs 42.01%);and high-volume suction(44.92% vs 11.19%).CONCLUSIONS The compliance with recommended infection control procedures among Beijing dentists is improving in 2005 vs 2000.More education and inspection is needed to develop the infection control practices in dental health care settings.

OBJECTIVE To investigate the application of low temperature hydrogen peroxide gas plasma sterilization in dental handpieces.METHODS Totally 240 pieces dental handpieces were divided into 8 groups in accordance with different ways of oiling and package,sterilized by Johnson STERRAD 100S low temperature hydrogen peroxide gas plasma sterilizer,and then inspected by sterility testing,rotational speed and appearance observation.RESULTS The result of sterility testing of dental handpieces in auto oiling group with 4 types of packages was negative,and the sterilization effect was reliable.After 10 cycles of low temperature hydrogen peroxide gas plasma sterilization,the rotational speed of dental handpieces had no obvious decline and the appearance was quite intact without any corrosion.CONCLUSIONS The sterilization effect is reliable and the damage caused by low temperature hydrogen peroxide gas plasma sterilization on dental handpieces is not found.

Objective To explore the levels and clinical significance of anti-beta 2-glycoprotein 1 antibodies (β_2GP1), matrix metalloproteinase 9 (M M P-9) in the plasma of children with Kawasaki diseases (KD). Methods Serum level of anti-β_2GP1 antibody and MMP-9 was measured in 47 children with KD by ELISA, and the data was analyzed using SPSS11.5 software. Thirty age matched children with infectious diseases(sepsis or pneumonia), exclusive of heart, liver, kidney, blood diseases and autoimmune diseases such as rheumatoid were chosen in the fever control group. Results Coronary artery lesions (CAL)were found in 17 children of KD group (17/47) by Doppler ultrasound examination. Significant differences (P < 0.05) of serum level of anti-β_2GP1 antibody was showed between KD group ((7.46 ± 2.13) U/ml)and the control group ((4.38 ± 0.43) U/ml) ; serum level of MMP-9 was (886.62 ± 92.72) ng/ml and (460.06 ± 179.59) ng/ml in KD group and the control group respectively, with significant difference between the two groups(P < 0.05). In KD group, levels of anti-β_2GP1 were (8.83 ± 0.89) U/ml among children with CAL and (6.18 ± 1.42) U/ml among children without CAL, serum level of MMP-9 was (948.62 ± 81.76) ng/ml and (872.00 ± 34.74) ug/ml respectively, with significant differences(beth P < 0.05). In children with KD, the serum levels of anti-β2GP1 antibody and MMP-9 were significantly correlated (correlation coefficient r = 0.665). Conclusions Serum levels of anti-β_2GP1 antibodies and MMP-9 increased in the acute phase of KD, and were significantly higher in those KD children with CAL.Anti-β_2GP1 antibodies and MMP-9 may play a role in the pathogenesis of KD, and can be used as an important serological indicator of KD with CAL.

Objective To evaluate the relationship between spectinomycin resistance in Neisseria gonorrhoeae and mutations in the rpsE gene.Methods Genomic DNA was extracted from 4 clinical isolates of Neisseria gonorrhoeae with different levels of spectinomycin resistance.Then,PCR was performed to amplify the entire rpsE gene and the spectinomycin resistance-determining region (SRDR) in the 16S rRNA gene followed by direct sequencing.Two spectinomycin-sensitive Neisseria gonorrhoeae strains were transformed with the genomic DNA containing the mutant rpsE gene.Subsequently,the susceptibility of the transformants to spectinomycin was determined,and PCR was performed to amplify the rpsE and 16S rRNA genes in the transformants followed by sequencing.Results All the 4 spectinomycin-resistant Neisseria gonorrhoeae strains harbored an A70C transversion in the rpsE gene,but no abnormality in the SRDR of the 16S rRNA gene.No mutations were detected in the spectinomycin-sensitive Neisseria gonorrhoeae strains.The A70C transversion in the rpsE gene was also detected in the two Neisseria gonorrhoeae transformants with spectinomycin resistance.Conclusion The A70C point mutation within the rpsE gene is associated with spectinomycin resistance in Neisseria gonorrhoeae.

Objective To study the association of U. urealyticum biovar and genotype with nongonococcal, nonchlamydial mucopurulent cervicitis. Methods The study population consisted of two groups: patient group (226 female patients with nongonococcal, nonchlamydial mucopurulent cervicitis) and control group (118 healthy women). The biovar and genotype of U. urealyticum were identified in specimens positive for U. urealyticum culture by using PCR-single-strand conformation polymorphism (PCR-SSCP) analysis. Results The most common genotype in both groups was mba 3/14 in biovar 1 with the detection rate being 30.98%(57/184) in patients with mucopurulent cervicitis and 43.42% (33/76) in the controls. A significant difference was observed in the prevalence of genotype 2B in biovar 2 between the patients and controls [16.30% (30/184) vs 6.58% (5/76), χ2 = 4.367, P= 0.037). The genotype 1, 3/14 and 6 in biovar 1 predominated in the controls with their total prevalence being 81.58%. Conclusion The genotype 2B in biovar 2 of U. urealyticum may be associated with nongonococcal, nonchlamydial mucopurulent cervicitis among female patients attending an STD clinic.

Objective To investigate the serovar distribution of Chlamydia trachomatis (Ct) isolated from male patients with urethritis in sexually transmitted disease (STD) clinic.Methods Urine specimens were collected from male patients with urethritis in STD clinic at Hospital of Dermatology,Chinese Academy of Medical Sciences between January 2013 and December 2013.Fluorescence-based quantitative PCR was performed to detect Ct DNA in these specimens.DNA was extracted from Ct-positive urine specimens,and nested PCR was conducted to amplify the VS1-VS2 regions of the outer membrane protein A (ompA) gene,followed by gene sequencing.The resulting sequences were aligned to reference sequences by the DNAStar5.0 software to determine Ct serovars.Results A total of 432 urine specimens were collected,and 33.1％ (143/432) of them were positive for Ct.The VS1-VS2 regions of the ompA gene were amplified from 127 out of the 143 Ct-positive specimens,but not from the other 16 specimens.Nine serovars were identified by gene sequencing among the 127 specimens,including serovar E (29 strains,22.83％),F (28 strains,22.05％),D (19 strains,14.96％),G (16 strains,12.60％),J (16 strains,12.60％),K (8 strains,6.30％),H (5 strains,3.94％),I (3 strains,2.36％) and B (3 strains,2.36％),and Ct serovars E,F,D,J and G accounted for 85.02％ among all the strains.Synonymous mutations were identified in 14 out of the 127 strains when compared with reference strains.Conclusions E,F,D and G serovars were the main Ct serovars in male patients with urethritis in STD clinic.The proportion of Ct serovar E strain was decreased,but that of serovar J strain was increased compared with 20 years ago.

Objective To study the relationship between M. Genitalium and nongonococcal, non-chlamydial mucopurulent cervicitis. Methods A total of 226 patients with nongonococcal, nonchlamydial mu copurulent cervicitis and 118 healthy female volunteers were recruited in this study. Cervical samples were collected and M.genitalium was detected by PCR amplification of 16s rRNA and Pa genes. Information about socio-demographic characteristics, medical history, and sexual behaviors was gathered by questionnaire from both populations. Results The prevalence of M. Genitalium infection was 11.06% (25/226) in patients with mucpurulent cervicitis, 0,85% (1/118) in the healthy controls; the difference was significant between the two groups (x2 = 11.58, P < 0.001). Single variant analysis on the 226 patients showed that the preva-lence of M. Genitalium infection was 27.78%, 16.36%, 18.28% and 14.12% in patients with ectopic pregnancy history, cervical inflammation, pelvic organ tenderness, 10 or more polymorphonuclear leukocytes (PMNs)per oil immersion field in cervical discharge, respectively, significantly higher than that in patients without ectopic pregnancy history, cervical inflammation or pelvic organ tenderness, and those with less than 10 PMNs per oil immersion field in cervical discharge (9.62%, 6.03%, 6.02% and 1.79%, all P < 0.05). M.genitalium infection was also related to multiple sex partners and the presence of mucopurulent secretion in cervix (P < 0.001). Conclusion The prevalence of M.genitalium infection is higher in patients with non-gonococcal, nonchlamydial mucopurulent cervicitis attending STD clinic than that in normal population.