Background: The testis has been reported to be a naturally O 2 -deprived organ, dimethyloxaloylglycine (DMOG) can inhibit hypoxia inducible factor-1alpha (HIF-1α) subject to degradation under normal oxygen condition in cells. Objectives: The objective of this study is to detect the effects of DMOG on the proliferation and differentiation of spermatogonial stem cells (SSCs) in Bama minipigs. Methods: Gradient concentrations of DMOG were added into the culture medium, HIF-1αprotein in SSCs was detected by western blot analysis, the relative transcription levels of the SSC-specific genes were analyzed using quantitative reverse transcription polymerase chain reaction (qRT-PCR). Six days post-induction, the genes related to spermatogenesis were detected by qRT-PCR, and the DNA content was determined by flow cytometry. Results: Results revealed that the levels of HIF-1α protein increased in SSCs with the DMOG treatment in a dose-dependent manner. The relative transcription levels of SSCspecific genes were significantly upregulated (p < 0.05) by activating HIF-1α expression. The induction results showed that DMOG significantly increased (p < 0.05) the spermatogenesis capability of SSCs, and the populations of haploid cells significantly increased (p < 0.05) in DMOG-treated SSCs when compared to those in DMOG-untreated SSCs. Conclusion We demonstrate that DMOG can promote the spermatogenesis activity of SSCs.

Objective To assess the diagnostic value of sweat conductivity testing in Chinese children with cystic fibrosis (CF). Methods This is a retrospective study. Sweat conductivity tests were conducted in 45 CF children (CF group) and 200 non‐CF children (non‐CF group) diagnosed with other chronic pulmonary diseases at the No. 2 Department of Respiratory Medicine, Beijing Children′s Hospital from May 2014 to June 2018. Pearson′s chi‐square test was used to assess the differences between CF and non‐CF groups. A receiver operating characteristic curve was constructed to calculate the best cut‐off value to diagnose or rule out CF. The pulmonary function parameters (forced expiratory volume in the first second, forced vital capacity,forced expiratory flows at 75% of exhaled vital capacity) of CF children over 6 years old were analyzed. The relationship between sweat conductivity and pulmonary function was compared between the two groups (80‐120mmol/L vs.>120mmol/L). Results The age of CF group was 9 (7, 12) years old, 19 males (42%) and 26 females(58%); the age of non‐CF group was 8 (5,11) years old, 106 males (53%) and 94 females(47%). The results of sweat conductivity test showed that sweat conductivity in CF group 108(99, 122) mmol/L was significantly higher than that in non‐CF group 43(36, 52) mmol/L (χ2=207, P<0.01). A cut‐off value of 80 mmol/L for CF diagnosis showed a sensitivity of 93.3% and a specificity of 98.5%. The receiver operating characteristic curve analysis suggested the best conductivity cut‐off value for the diagnosis of CF was at 83.5 mmol/L,with a sensitivity of 93.3% and a specificity of 100%,and an area under the curve of 0.993 (95% confidence interval 0.985-1.000). The best conductivity cut‐off value to rule out CF diagnosis was at 63.5 mmol/L,with a sensitivity of 97.8% and a specificity of 90.5%. There was no correlation between the level of sweat conductivity and the extent of pulmonary function decline. Conclusions Sweat conductivity testing can be used for the screening of CF in Chinese children. A diagnosis of CF should be considered if the value is greater than 80 mmol/L.

【Objective】 To analyze the effect of sample hemolysis on ELISA test results in blood screening laboratory, so as to determine the acceptable tolerance of hemolysis specific to laboratory test items and detection system, and provide reference for the formulation of tolerance standard of sample hemolysis. 【Methods】 Negative and weakly positive (S/CO was about 2) samples with different hemolysis degrees were tested by several commonly used domestic reagents for HBsAg, HIV Ag/Ab, anti-HCV and anti-TP, respectively. The effects of various degrees of hemolysis on the test results of negative and weakly positive samples for each item were analyzed. 【Results】 1) Hemolysis had no effect on the test results (reactive/non-reactive) of negative and weakly positive samples for HBsAg, anti-HCV and anti-TP ELISA items; 2) Hemolysis affected the test results (reactive/non-reactive) of negative and weakly positive samples for HIV Ag/Ab ELISA item. A tolerance of Hb 2 g/L was taken as the acceptable hemolysis degree for HIV Ag/Ab ELISA item. 【Conclusion】 In this study, the acceptable tolerance of hemolytic samples for corresponding test items and detection system in our laboratory were determined. The influence of hemolysis on ELISA test result is related to the reagent, equipment, environment and other factors, therefore the acceptable tolerance of hemolysis should be determined scientifically and reasonably based on the specific evaluation of each laboratory.

Objective: To assess the diagnostic value of sweat conductivity testing in Chinese children with cystic fibrosis (CF). Methods: This is a retrospective study. Sweat conductivity tests were conducted in 45 CF children (CF group) and 200 non-CF children (non-CF group) diagnosed with other chronic pulmonary diseases at the No. 2 Department of Respiratory Medicine, Beijing Children′s Hospital from May 2014 to June 2018. Pearson′s chi-square test was used to assess the differences between CF and non-CF groups. A receiver operating characteristic curve was constructed to calculate the best cut-off value to diagnose or rule out CF. The pulmonary function parameters (forced expiratory volume in the first second, forced vital capacity,forced expiratory flows at 75% of exhaled vital capacity) of CF children over 6 years old were analyzed. The relationship between sweat conductivity and pulmonary function was compared between the two groups (80-120mmol/L vs.>120mmol/L). Results: The age of CF group was 9 (7,12) years old, 19 males (42%) and 26 females(58%); the age of non-CF group was 8 (5,11) years old, 106 males (53%) and 94 females(47%). The results of sweat conductivity test showed that sweat conductivity in CF group 108(99, 122) mmol/L was significantly higher than that in non-CF group 43(36, 52) mmol/L (χ²=207, P<0.01). A cut-off value of 80 mmol/L for CF diagnosis showed a sensitivity of 93.3% and a specificity of 98.5%. The receiver operating characteristic curve analysis suggested the best conductivity cut-off value for the diagnosis of CF was at 83.5 mmol/L,with a sensitivity of 93.3% and a specificity of 100%,and an area under the curve of 0.993 (95% confidence interval 0.985-1.000). The best conductivity cut-off value to rule out CF diagnosis was at 63.5 mmol/L,with a sensitivity of 97.8% and a specificity of 90.5%. There was no correlation between the level of sweat conductivity and the extent of pulmonary function decline. Conclusions Sweat conductivity testing can be used for the screening of CF in Chinese children. A diagnosis of CF should be considered if the value is greater than 80 mmol/L.