ABSTRACT
Objective To investigate the best experimental scheme of Mycoplasma solid culture combined with liquid culture.Methods A total of 961 samples of urogenital tract excretion were collected from March 2016 to June 2016.Both solid culture and liquid culture were performed for detection of Mycoplasma,false positive broths were picked out after 48 h,20 μl of each one was transformed to solid media for subculture,final results were read after 48 h.The experimental data was analyzed to find an optimal combination culture scheme.Results The positive rate of solid culture was 38.7％ (372/961) for UU and 7.8％ (75/961) for MH.The positive rate of liquid culture was 45.27％ (435/961) for UU and 7.08％ (68/961) for MH.The different rate between both methods was 9.47％ (91/961) for UU (x2 =43.61,P＜0.005),and 3.02％ (29/ 961) for MH (x2 =1.24,P＞ 0.05).The different rate was 53.5 ％ (46/86) between primary solid culture and subculture.The positive rate of total (primary solid culture and subculture) solid culture was 41.9％ (403/961) for UU and 8.6％ (83/961) for M H,which produced higher sensitivity than single (primary solid culture or subculture) solid culture.The different rate between the total solid culture and the liquid method was 6.24 ％ (60/961) for UU (x2 =17.067,P＜0.05),and 3.43 ％ (33/961) for MH (x2=5.94,P＜0.05).Conclusion Perform both solid culture and liquid culture for Mycoplasma,pick out those false positive broths for subculture.Total solid culture could be more reliable as final result,for which could combine specificity of solid culture with sensitivity of liquid culture.
ABSTRACT
Objective To investigate the drug-resistance of Staphylococcus aureus induced by erythromycin in vitro and its changes in growth and susceptibility of antibiotics.Methods Erythromycin in vitro induction was conducted with the S.au-reus reference strain ATCC25923 on the serial of erythromycin agar plates.The growth of S.aureus,and the susceptibility a-gainst other antibiotics was compared after induced to the parent strain.Results Resistance to erythromycin was successful-ly,and themaximum MIC was over 256 mg/L.The Erythromycin-resistant S.aureus grew much slower than the susceptible parent,and the strains didn’t have cross-resistance to other antibiotics.Conclusion S.aureus could be induced resistance in vitro by erythromycin,and this resistance inherited stably.Some phenotype and biochemical characteristic features of the strain were changed after induced.
ABSTRACT
Objective To investigate the application value of 16S rDNA-based detection technique in the rapid screening for and confirmation of gonococcemia. Methods A 41-year-old male patient was hospitalized for recurrent regular fever and chills for 1 month. Several days before the admission, he developed urgent micturition, frequent micturition and pain in urination, anemia with emaciation appearance, slightly pale-looking skin and mucous membranes. No petechia, skin eruption or superficial lymphadenectasis was observed, but routine blood test and urine test results were abnormal. No abnormality was found in stool test or hepatic and renal function. DNA was extracted from the blood of the patient and subjected to PCR for the amplification of 16S rDNA followed by sequence analysis and homology analysis. At the same time, bacterial culture of blood and drug sensitivity test for the bacterial isolate were performed. Results Homology analysis indicated that the amplicon sequence was consistent with the known sequence of 16S rDNA of Neisseria gonorrhoeae in GeneBank, which agreed well with the culture result of peripheral blood. Conclusion The detection of 16s rDNA with PCR from peripheral blood is highly efficient, specific, sensitive, rapid and accurate for the screening for and confirmation of gonococcemia.