Objective: To develop a sensitive, specific and simple method for detection of extremely low numbers of T. pallidum in clinical specimens, as a significant addition to the serologic tests for syphilis diagnosis. Metho...Objective: To develop a sensitive, specific and simple method for detection of extremely low numbers of T. pallidum in clinical specimens, as a significant addition to the serologic tests for syphilis diagnosis. Methods: Double-tube nested PCR(DN-PCR) and single-tube nested PCR(SN-PCR) assays were performed to amplify specific fragments of the DNA poly-merase I gene(polA) of T. pallidum. Sensitivity and specificity of the two PCR assays were tested. Eighty-six whole blood specimens from persons with suspected syphilis were detected by the two nested PCR methods. The TPPA test was used as a comparison for detecting syphilis in sera from corresponding patients. Results: Only specific amplicons could be obtained during amplification of the T. pallidum polA gene and the detection limit was approximately 1 organism when analyzed on gel by the two PCR methods. Of 86 clinical specimens, 62 were positive by TPPA. Of these, 54 and 51 were positive by the DN-PCR and SN-PCR, respectively, which does not represent a statistically significant difference between the two PCR tests. Of 24 TPPA-negative specimens, 5 were positive by both DN-PCR assay and SN-PCR assay. Conclusion: The SN- polA PCR method is extremely sensitive, specific and easy to perform for detecting low numbers of T. pallidum in clinical blood specimens as a complementary to serology for syphilis diagnosis.展开更多
Ventral globus pallidus-injured rats by kainic acid(10 mg) were used to derter-mine the monoamine levels in four different brain regions.In this model,a great decrease of NE con-centration was observed in both hippoca...Ventral globus pallidus-injured rats by kainic acid(10 mg) were used to derter-mine the monoamine levels in four different brain regions.In this model,a great decrease of NE con-centration was observed in both hippocampus and frontal cortex compared with nonnal contro.This result hints that a damage of noradrenergic neurons in this model has occurred. DA concentrations in the four brain zones after kainic acid injection were all reduced, but only in the frontal cortex and striatum the pronounced reductions were discovered while DA turnover rates in frontal cortex, stria-tum and meddullapons were significantly reduced. These results revealed a DA metabolic disorder occurring in these regions.However,5-HT concentrations as well as DBH activity, expressed by ratio of NE/DA,showed no marked difference in this model. In our study it is found that the changes of monoamine levels in this model basically reflect those discovered in AD patients.展开更多
Objectives: To develop a method of simultaneous PCR detection of Haemophilus ducreyi, Treponema pallidum, andHerpes Simplex Virus Types 1 and 2 from genital ulcersamong patients attending STD clinics in Guangzhou, Chi...Objectives: To develop a method of simultaneous PCR detection of Haemophilus ducreyi, Treponema pallidum, andHerpes Simplex Virus Types 1 and 2 from genital ulcersamong patients attending STD clinics in Guangzhou, China;and evaluate the clinical application of multiplex PCR (M-PCR) assay for diagnosing the etiology of genital ulcerdiseases (GUD). Methods: 244 patients with a genital ulcer were evaluated.Clinical etiology of GUD was based on physical appearanceand microbiologic evaluations that included darkfieldmicroscopy examination (D-F) and serology test for syphilis(STS). Swabs of each genital ulcer were tested for HSVantigen by enzyme immunoassay (EIA) and processed in anM-PCR assay for simultaneous detection of T pallidum, HSVand H ducreyi. Results: The standard strains of T pallidum, HSV and Hducreyi were amplified by M-PCR, producing amplifiedproducts of 260bp,432bp,170bp, respectively. The sensitivityof M-PCR is 10~2 pg DNA. M-PCR assay for T.pallidum, HSVand H ducreyi showed good agreement en compared with D-F detection for T pallidum, STS, H ducreyi culture and EIAfor HSV antigen (Kappa scores are 0.774,0.704,0.793,0.756,respectively). Conclusions: The M-PCR is a convenient, accurate andreliable assay for the detection of T pallidum, HSV and Hducreyi from genital ulcers, and can be used as a method ofdiagnosing the etiology of GUD.展开更多
文摘Objective: To develop a sensitive, specific and simple method for detection of extremely low numbers of T. pallidum in clinical specimens, as a significant addition to the serologic tests for syphilis diagnosis. Methods: Double-tube nested PCR(DN-PCR) and single-tube nested PCR(SN-PCR) assays were performed to amplify specific fragments of the DNA poly-merase I gene(polA) of T. pallidum. Sensitivity and specificity of the two PCR assays were tested. Eighty-six whole blood specimens from persons with suspected syphilis were detected by the two nested PCR methods. The TPPA test was used as a comparison for detecting syphilis in sera from corresponding patients. Results: Only specific amplicons could be obtained during amplification of the T. pallidum polA gene and the detection limit was approximately 1 organism when analyzed on gel by the two PCR methods. Of 86 clinical specimens, 62 were positive by TPPA. Of these, 54 and 51 were positive by the DN-PCR and SN-PCR, respectively, which does not represent a statistically significant difference between the two PCR tests. Of 24 TPPA-negative specimens, 5 were positive by both DN-PCR assay and SN-PCR assay. Conclusion: The SN- polA PCR method is extremely sensitive, specific and easy to perform for detecting low numbers of T. pallidum in clinical blood specimens as a complementary to serology for syphilis diagnosis.
文摘Ventral globus pallidus-injured rats by kainic acid(10 mg) were used to derter-mine the monoamine levels in four different brain regions.In this model,a great decrease of NE con-centration was observed in both hippocampus and frontal cortex compared with nonnal contro.This result hints that a damage of noradrenergic neurons in this model has occurred. DA concentrations in the four brain zones after kainic acid injection were all reduced, but only in the frontal cortex and striatum the pronounced reductions were discovered while DA turnover rates in frontal cortex, stria-tum and meddullapons were significantly reduced. These results revealed a DA metabolic disorder occurring in these regions.However,5-HT concentrations as well as DBH activity, expressed by ratio of NE/DA,showed no marked difference in this model. In our study it is found that the changes of monoamine levels in this model basically reflect those discovered in AD patients.
基金Financially supported by Foundation for Major Projects of Guangdong Province(No.99049)Medical Research Foundation of Guangdong Province(No.B2001100)
文摘Objectives: To develop a method of simultaneous PCR detection of Haemophilus ducreyi, Treponema pallidum, andHerpes Simplex Virus Types 1 and 2 from genital ulcersamong patients attending STD clinics in Guangzhou, China;and evaluate the clinical application of multiplex PCR (M-PCR) assay for diagnosing the etiology of genital ulcerdiseases (GUD). Methods: 244 patients with a genital ulcer were evaluated.Clinical etiology of GUD was based on physical appearanceand microbiologic evaluations that included darkfieldmicroscopy examination (D-F) and serology test for syphilis(STS). Swabs of each genital ulcer were tested for HSVantigen by enzyme immunoassay (EIA) and processed in anM-PCR assay for simultaneous detection of T pallidum, HSVand H ducreyi. Results: The standard strains of T pallidum, HSV and Hducreyi were amplified by M-PCR, producing amplifiedproducts of 260bp,432bp,170bp, respectively. The sensitivityof M-PCR is 10~2 pg DNA. M-PCR assay for T.pallidum, HSVand H ducreyi showed good agreement en compared with D-F detection for T pallidum, STS, H ducreyi culture and EIAfor HSV antigen (Kappa scores are 0.774,0.704,0.793,0.756,respectively). Conclusions: The M-PCR is a convenient, accurate andreliable assay for the detection of T pallidum, HSV and Hducreyi from genital ulcers, and can be used as a method ofdiagnosing the etiology of GUD.
