[Correlation of age, body mass index and obesity-related biochemical indexes with semen quality in males intending for a second child].

OBJECTIVE: To explore the influence of age, body mass index (BMI) and obesity-related biochemical indexes on semen quality in adult males intending to have a second child in Guangzhou. METHODS: We conducted a questionnaire investigation among 632 adult males seeking medical advice on their intention for a second child at Guangzhou Women and Children's Medical Center from August 2017 to July 2018. We obtained their lipid metabolism indicators and semen parameters, and analyzed the correlation of semen quality with age, BMI, obesity-related biochemical indexes, living environment and occupation. RESULTS: Age, BMI, season of sperm extraction, living environment and occupation all influenced the semen quality of the males. Age was correlated negatively with the percentage of progressively motile sperm (PMS) (r = －0.109, P < 0.05), BMI positively with the semen volume (r = 0.103, P < 0.05) but negatively with the percentage of morphologically normal sperm (MNS) (r = －0.138, P < 0.05), high-density lipoprotein (HDL) negatively with PMS (r = －0.168, P < 0.01) and the percentage of immotile sperm (IM) (r = －0.135, P < 0.05), low-density lipoprotein (LDL) negatively with the semen volume (r = －0.124, P < 0.01), PMS (r = －0.127, P < 0.05), sperm concentration (r = －0.121, P < 0.05) and total sperm count (r = －0.210, P < 0.01) but positively with IM (r = 0.140, P < 0.01). Multivariate regression analysis showed BMI and LDL to be independent factors influencing the semen volume, uric acid to be an independent factor influencing semen liquefaction time, age, HDL and LDL to be independent factors influencing PMS, age, and HDL to be independent factors influencing IM, LDL to be independent factors influencing total sperm count, while BMI and TG to be independent factors influencing MNS. CONCLUSIONS: Age, BMI, season of sperm extraction, living environment and occupation may affect the semen quality of the males in Guangzhou.

[Evaluation of strand displacement amplification in the diagnosis of tuberculosis].

OBJECTIVE: To study the clinical significance and reliability of strand displacement amplification (SDA) in detecting Mycobacterium tuberculosis complex. METHODS: SDA and fluorescence quantitative polymerase chain reaction (FQ-PCR) were employed to detect samples from 453 cases of tuberculosis, including 332 sputum samples, 78 samples of pleural effusion, and 43 samples of cerebrospinal fluid. RESULTS: In the 332 sputum samples, 131 were culture-positive, of which 110 samples (88 smear-positive) were Mycobacterium tuberculosis complex and 21 samples (20 smear-positive) were nontuberculous Mycobacteria. The sensitivity and specificity of SDA for the 110 samples of Mycobacterium tuberculosis complex and 21 samples of nontuberculous Mycobacteria were 99.1%, 95.2% and 94.6%, 95.2%, respectively. The positive rates in the 311 cases of Mycobacterium tuberculosis complex for SDA and FQ-PCR were 55.3% (172/311) and 47.0% (146/311), respectively. There were 20 smear positive samples in the 121 samples of pleural effusion and cerebrospinal fluid, of which 19 were Mycobacterium tuberculosis, 1 nontuberculous Mycobacterium. The positive rates for SDA and FQ-PCR were 43.4% (52/120) and 33.4% (40/120), respectively. Internal amplification control (IAC) was designed for SDA to achieve accuracy of the results. CONCLUSION: The automatic assay system of SDA is a rapid and specific test for detecting Mycobacterium tuberculosis complex.