Background The hearing of Chinese young adults is far less sensitive than 0 dB defined by international standards, with the threshold values mostly being at double digits, which is worthy of investigation. Objective To study the influencing factors of hearing threshold measurement. Methods The hearing measurements were conducted in two different ways, one was a standard method performed in a specialized audiometry experiment room, and the other one was an on-site audiometry test which included a daily examination of hearing and an onsite hearing test. From the workers who participated in the occupational health examination, 300 people were randomly selected as experimental subjects, and their hearing was measured in the hearing examination room of the Occupational Disease Prevention and Treatment Institute according to standard methods. A total of 9 766 workers from the General Motors factory were included in the daily group, and their hearing thresholds were measured in the hearing examination room in the factory. There were 4 617 people in the onsite group, and their hearing was measured in the test chamber of our mobile medical vehicle in their factories. The hearing threshold data of the three groups, i.e. experiment, daily examination and on-site, was compared and analyzed. In addition, the environmental noise in the hearing examination room and the mobile test chamber was measured. Results The hearing threshold value of the experimental group was the lowest. Despite this, its dB value remained at double digits at any frequency band. The hearing value of the daily group was in the middle. The onsite group had the highest hearing threshold, which was 58.2% higher than that of the experimental group. As the hearing data was not normally distributed, Kruskal-Wallis non-parametric test was conducted for statistical analysis. It was found that the hearing threshold difference among the three groups was statistically significant at all the frequency band (P< 0.01). The ambient noise level was 23.9-28.3 dB(A) in the hearing examination room, and 32.5 - 67.9 dB (A) in the mobile test chamber. Age and gender were not confounding factors to the results. Conclusion The hearing test method and its environmental noise were able to make the threshold measurements shift up significantly. The environmental noise of the mobile test chamber in the examination vehicle has exceeded the standard and needs to be improved.

OBJECTIVE: To investigate the efficacy and safety of aromatase inhibitor letrozole in treatment of male children with disorders of sex development (DSD). METHODS: Clinical data of 12 male DSD children with a mean age of 14.6±2.5 years admitted to Peking Union Medical College Hospital from January 2014 to January 2016 were retrospectively analyzed. The patients were treated with letrozole (1.25-2.5 mg, once a day) for 3 months or longer, and followed up for 0.5-2.5 years. Clinical manifestation and laboratory test findings were documented, and the efficacy and safety were evaluated. RESULTS: After half-year treatment, the blood luteinizing hormone (LH), follicle-stimulating hormone (FSH) and testosterone levels of patients increased (all < 0.05), and estrogen levels decreased from baseline ( < 0.05). After 1 year of treatment, the blood testosterone level was significantly higher ( < 0.05); the LH and FSH levels tended to increase and the estrogen level tended to decrease, but there was no significant statistical difference ( >0.05). Semen was routinely detected in 8 patients, and sperms were detected in semen of 3 patients with hypospadias. There were no significant changes in biochemical results after treatment, and no significant adverse event was observed during the treatment. CONCLUSIONS Letrozole can effectively increase testosterone levels in patients with disorders of sex development and promote spermatogenesis, it has no significant adverse effects in short-term administration.
Adolescent ; Child ; Disorders of Sex Development ; drug therapy ; Follicle Stimulating Hormone ; Humans ; Letrozole ; therapeutic use ; Luteinizing Hormone ; Male ; Retrospective Studies ; Testosterone

Mammalian reproduction is closely related to their metabolic status. The hypothalamus-pituitary-gonad axis ( HPG axis) is regulated by various metabolic factors. Glucagon-like peptide-1 ( GLP-1) is one of various metabolic factors that not only affect glycemic and metabolic control, but also with many other effects, including affecting HPA axis. The function of GLP-1 is related to the location of glucagon-like peptide-1 receptor ( GLP-1R) distribution. It has been confirmed that GLP-1R is widely distributed in HPG axis. The effects of GLP-1 and GLP-1R agonists on the HPG axis have also attracted much attention. The positive effects of GLP-1 and GLP-1R agonists on the HPG axis indicated it could be the new target for the new treatment for gonadal diseases. The role of GLP-1 and GLP-1R agonists in the central nervous system is reviewed.

OBJECTIVE： To investigate the proportion of 8 kinds of ginsenoside to ginsenoside Rg1 in Panax ginseng and the regularity of growth year in Jilin province， and to provide reference for the identification of growth year. METHODS： The samples of garden ginseng， wild-cultivated ginseng and wild ginseng were collected from different growth years （3-30 years） in Jilin province. The contents of 8 ginsenoside （ginsenoside Rg1， Re， Rf， Rb1， Rc， Rb2， Rb3， Rd） in P. ginseng were determined by HPLC. The contents of saponins as well as the proportion of 8 kinds of ginsenoside to ginsenoside Rg1 were calculated； the relationship of the proportion with growth year was investigated. RESULTS： As the increase of growth year， the proportion of 8 kinds of ginsenosides in garden ginseng to ginsenoside Rg1 as well as that of ginsenoside Re， Rb1， Rc， Rd to ginsenoside Rg1 were decreased gradally （P＜0.001）； the proportion of ginsenoside Re to ginsenoside Rg1 in wild-cultivated ginseng decreased first and then increased（P＜0.001）； the proportion of 8 kinds of ginsenosides to ginsenoside Rg1 as well as the proportion of ginsenoside Re and Rb1 to ginsenoside Rg1 were increased gradually in wild ginseng （P＜0.001）； the proportion of ginsenoside Rf， Rb3 to ginsenoside Rg1 in garden ginseng， wild-cultivated ginseng and wild ginseng had no significant difference（P＞0.05）. CONCLUSIONS： Garden ginseng， wild-cultivated ginseng and wild ginseng contain 8 kinds of ginsenosides. The growth year can be predicted preliminarily according to the proportion of ginsenoside Rg1 and ginsenoside Re， Rb1 to ginsenoside Rg1.

Objective To knockout the MATP gene of mouse melanoma cell line B16F10 using CRISPR/Cas9 system,and to lay foundation for the functional study of MATP gene.Methods Specific primers of MATP were designed according to the report in http://crispr.mit.edu/ website.The primers were linked to pCAS9/gRNA1 vector.Then the positive vector was transfected into mouse melanoma B16F10 cells,and monoclonal cell lines were obtained by the infinite dilution method.After the genomes of different monoclonal cell lines were extracted and sequenced,the cell lines with MATP gene cleavage were screened,and the expression of MATP in these cell lines was verified by Western-blot analysis.Results Three MATP gene knockout cell lines were successfully obtained.The western-blot results showed that the cell lines did not express MATP protein.Conclusions The knockout of MATP gene in B16F10 cell line can be successfully achieved using the pCAS9/gRNA1 vector.

Objective: To evaluate the influence of oral hygiene on risk of oral cancer in non-smoking and non-drinking women. Methods: From September 2010 to February 2016, 242 non-smoking and non-drinking female patients with pathologically confirmed oral cancer were recruited in a hospital of Fuzhou, and another 856 non-smoking and non-drinking healthy women from health examination center in the same hospital were selected as control group. Five oral hygiene related variables including the frequency of teeth brushing, number of teeth lost, poor prosthesis, regular dental visits and recurrent dental ulceration were used to develop oral hygiene index model. Unconditional logistic regression was used to calculate odds ratios (OR) and 95% confidence intervals (95%CI). The area under the receiver operating characteristic curve (AUROC) was used to evaluate the predictability of the oral hygiene index model. Multivariate logistic regression model was used to analyze the association between oral hygiene index and the incidence of oral cancer. Results: Teeth brushing <2 twice daily, teeth lost ≥5, poor prosthesis, no regular dental visits, recurrent dental ulceration were risk factors for the incidence of oral cancer in non-smoking and non-drinking women, the corresponding OR (95%CI) were 1.50 (1.08-2.09), 1.81 (1.15-2.85), 1.51 (1.03-2.23), 1.73 (1.15-2.59), 7.30 (4.00-13.30), respectively. The AUROC of the oral hygiene index model was 0.705 9, indicating a high predictability. Multivariate logistic regression showed that the oral hygiene index was associated with risk of oral cancer. The higher the score, the higher risk was observed. The corresponding OR (95%CI) of oral hygiene index scores (score 1, score 2, score 3, score 4-5) were 2.51 (0.84-7.53), 4.68 (1.59-13.71), 6.47 (2.18-19.25), 15.29 (5.08-45.99), respectively. Conclusion Oral hygiene could influence the incidence of oral cancer in non-smoking and non-drinking women, and oral hygiene index has a certain significance in assessing the combined effects of oral hygiene.

Objective: To investigate the effects between fish, seafood and pickled food intakes on oral squamous cell carcinoma (OSCC). Methods: A case-control study was carried out in Fujian area during September 2010 to December 2016, in which 604 newly diagnosed primary OSCC cases confirmed by pathological diagnosis were collected from hospital and 1 343 control subjects were enrolled from community and healthy hospital population. Demographic data, history of smoking drinking and tea drinking, oral hygiene status and dietary behaviors (fish, seafood and pickled food intakes) were collected by in-person interviews using a standard questionnaire.Using unconditional logistic regression to estimate adjusted odds ratios (ORs) and corresponding 95% confidence intervals (CIs) to assess the effects of fish, seafood and pickled food intakes on OSCC. Analysis stratified by smoking, alcohol drinking and bad prosthesis to explore the possible difference in association between subgroups. Multiplicative interactions and additive interactions between fish and bad prosthesis, seafood and alcohol drinking, pickled food and bad prosthesis were assessed by unconditional logistic regression, relative excess risk due to interaction (RERI), attributable proportion due to interaction (AP) and synergy index (S). Results: The average age of case group and control group were separately (58.69±13.92) years old and (59.27±11.37) years old (χ²=4.75, P=0.191). The people whose fish and seafood intakes ≥3 times/week had the lower risk of OSCC, the adjusted OR (95%CI) values were 0.63 (0.52-0.77) and 0.51 (0.41-0.64); The stratified analysis indicated that the people having bad prosthesis had the lower risk of OSCC if they eating fish ≥3 times/week, and the adjusted OR (95%CI) values was 0.53 (0.39-0.71); the people having bad prosthesis had the higher risk of OSCC if they eating pickled food ≥3 times/week, the adjusted OR (95%CI) values was 1.37 (1.02-1.88). Regularly eating seafood can decrease the risk of OSCC for non-smokers, smokers, non-drinkers, drinkers, people without bad prosthesis and had bad prosthesis, the adjusted OR (95%CI) values were 0.49 (0.36-0.68), 0.52 (0.37-0.73), 0.41 (0.31-0.55), 0.77 (0.51-0.96), 0.49 (0.36-0.67), 0.59 (0.42-0.83). Crossover analysis showed fish and bad prosthesis exist multiplication interaction relationship (adjusted OR=0.66, 95%CI: 0.44-0.97) and additional interaction relationship (RERI=-0.81, 95%CI:-1.43--0.19; AP=-0.76, 95%CI:-1.35--0.17; S=0.08, 95%CI: 0.01-0.98); pickled food and bad prosthesis exist multiplication interaction relationship (adjusted OR=1.63, 95%CI: 1.06-2.51) and addition interaction relationship (RERI=0.65, 95%CI:0.08-1.22; AP=0.36, 95%CI:0.10-0.62; S=5.19, 95%CI:1.32-54.49). Conclusion Reducing the consumption of pickled food, quitting smoking and limiting alcohol consumption, and regularly eating fish and seafood can prevent the occurrence of OSCC.

Objective To investigate the expression of transcription factor Oct 4 in gastric carcinoma and its effects on gastric cancer cell proliferation and apoptosis after Oct 4 gene interfered by lentivirus vector.Methods Real time PCR and Western blot were used to observe the expression of Oct 4 in different differentiated gastric cancer cell lines.Gastric cancer cell lines with high expression of Oct 4 was cultured and infected by siRNA-Oct 4-lentivirus vector.Cell proliferation and apoptosis were observed after Oct 4 gene was interfered.Results Oct 4 was highly expressed in poorly and moderately differentiated gastric cancer cells.Gene interfered with siRNA inhibits the expression of Oct 4 in gastric cancer cells and show significant effects on cell proliferation and mobility as well as apoptosis after down-regulation of Oct 4.Condusions Oct 4 expression is in close relationship with gastric cancer cell proliferation and invasive ability.

AIM:To establish a fast , accurate and economical technique for culturing mouse pulmonary arte-riolar smooth muscle cells ( PASMCs ) , and to explore the effects of hypoxia on the proliferation and apoptosis of the PASMCs.METHODS:In sterile condition, the pulmonary artery was isolated from the male BALB/c mice by digesting with collagenase I, and the cells were cultured in fetal bovine serum-coated flask.Centrifugal procedure was not used dur-ing the cell passage .The cell morphology was observed under an inverted phase-contrast microscope .α-Smooth muscle ac-tin was identified by immunocytochemistry and immunofluorescence .The effects of hypoxia on the proliferation and apopto-sis of the PASMCs were detected by CCK-8 assay and TUNEL assay .RESULTS:PASMCs were identified by the methods of immunocytochemistry , immunofluorescence staining and observation of morphology .Unlike the rat PASMCs with typical subcultured peak-vally pattern, the mouse PASMCs showed a lot different without a peak-vally pattern.The cells could be subcultured after 5 d to 7 d and there was 3 to 5 generations depending on the activity of the cells .CCK-8 assay demonstra-ted that the A values of PASMCs exposed to hypoxia increased after 24 h ( P<0.05) as compared with normoxia .TUNEL result showed that the apoptotic index of the PASMCs in hypoxia decreased after 24 h (P<0.05).CONCLUSION:This technique for obtaining cultured mouse PASMCs is simple , fast, accurate and economical .The digestion time is easy to control.Hypoxia promotes the proliferation and inhibits the apoptosis of PASMCs .

Objective To develop a method for rapid and accurate detection and identification of bacterial pathogens directly from body fluid specimens and to evaluate its application in clinical laboratory.Methods Bacteria DNA was extracted from 205 body fluid specimens with column-based kit,and the high variable V1 and V3 regions of bacterial 16S rRNA gene were amplified with broad-range primers.Amplicons were analyzed by pyrosequencing and the generated sequences were searched in the bacterial identification database.Traditional culture-biochemical method was also used for these specimens and the results were taken as the golden standard.SPSS 11.0 was used to calculate the sensitivity,specificity,false positive/negative rate,positive/negative predictive value and positive/negative likelihood rate of pyrosequencing method.Results The positive rate of bacteria culture was 39.5％ (81/205),among which 71 were infected with single bacterium,and 10 were infected with two species of bacteria.Compared with the culture identification results,pyrosequencing had a 100.0％ (71/71) concordance when applied to detect and identify bacterial pathogens from specimens with single specie bacterium infected.To specimens with two species bacteria infected,7 out of 10 specimens were in concordance with the culture identification results.Besides,pyrosequencing detected 10 positive specimens and identified bacterial pathogens infected in the 124 culture-negative specimens.Taken bacteria culture as the standard method,the sensitivity of pyrosequencing for identifying bacterial pathogen in body fluid was 100.0％,and with a specificity of 91.9％,the false positive rate was 8.1％,the false negative rate was 0.0％,the positive predictive value was 89.0％,the negative predictive value was 100.0％,and the positive and the negative likelihood rate were 12.4 and 0,respectively.Conclusion Pyrosequencing can be used to detect and identify bacterial pathogens directly from body fluid specimens with the advantages of rapidity,high sensitivity,high accuracy and high throughput.