OBJECTIVETo establish a rapid determination method with gas chromatography-mass spectrometer (GC-MS) for thiodiglycolic acid (TDGA), a vinyl chloride (VCM) biomarker.

METHODSA high- sensitivity determination method was established using a moderate methyl esterification instead of methyl esterification of highly toxic diazo reaction.

RESULTSThe standard curve regression linear equation of the method was: y=8460.5x-4758.2, the linear coefficient was 0.999 7, the minimum quantity concentration was 2.0 µg/L, the range of precision value was 0.81%-2.38%, and the average recovery of standard addition was 99.0%-102.9%.

CONCLUSIONThis method reduces the risk of traditional methyl esterification, improves the determination sensitivity compared with the GC-FPD method, and meets the determination requirement of TDGA.

Air Pollutants, Occupational ; analysis ; Chromatography, Gas ; methods ; Dimethyl Sulfoxide ; analysis ; Workplace

Objective: To assess psychological acceptance and occupational stress of medical staff, analyze the relationship among personality, psychological acceptance and occupational stress and discuss the direct or indirect effects of personality to occupational stress. Methods: The gaseous four kinds of carboxylic acids in the workplace air were simultaneously collected by silica gel tube, and then desorbed by deionized water and eluted by ion chromatograph. The the content was detected by conductivity detector. Results: The linear relationship was good in the concentration range of about 0~140 mg/L. The correlation coefficient r>0.999, and the maximum detection limit was 4.5 μg/mL. The sampling efficiency of the four carboxylic acids ranges from 96.10%~100.27%. Through the sample added recovery experiments, the low and high content of the silicone tube samples were detected; and the range of desorption efficiency was 82.18%~100.12%; the range of precision was 0.70%~3.71%. Conclusion This method adopts deionized water to desorb samples, and the application of ion chromatography detection have reached the requirements of《Guidelines for the establishment of occupational health standards, Part 4: Determination of chemical substances in workplace air》, which can be used in four kinds of workplace air detection of carboxylic acid compounds.

Air Pollutants, Occupational ; analysis ; Butylene Glycols ; analysis ; Chromatography, Gas ; Workplace

Objective: To establish an HPLC method for determining p-Anisidine in workplace air. Methods: An C₁₈ capillary column was used with the detection wavelength of 240 nm, the methanol solution (v/v=62:38) as mobile phase, the flow rate was 0.9 ml/min, and the injection volume was 20 μl. Results: The linear range (μg/ml) for p-Anisidine was 0~100; correlation coefficient was 0.999 7; the detection limit was 0.15 μg/ml; the average precision of RSD was 4.4%. The sampling efficiency was more than 95% using silicone tube as sampling filter. Sample can be stored at room temperature for more than 7 d. Conclusion the method appered to be accurate, simple, sensitive and reliable, also have a high sampling efficiency, and can be usd to determine p-anisidine in workplace air simultaneously.

Objective:To explore the diagnosis, treatment and prognostic of pediatric intracranial atypical teratoid/rhabdoid tumor(AT/RT).Methods:A total of 15 pediatric patients with intracranial AT/RT were treated between January 2012 and June 2019 at the First Affiliated Hospital of Zhengzhou University.The clinical data were retrospectively analyzed.Overall survival (OS) rate and progression free survival (PFS) rate were calculated by adopting Kaplan- Meier method.The differences between the 2 groups were tested by performing Log- rank method, and the prognostic factors were analyzed by COX regression. Results:There were 12 males and 3 females, with the median age of 5.5 years (ranging from 8 months to 17.1 years). All patients underwent surgical resection.Gross-total resection (GTR) was achieved in 10 cases and subtotal resection (STR) was carried out in 5 patients.The conducted treatments were as follows: surgery+ radiotherapy+ chemotherapy+ intrathecal injection in 6 cases, surgery+ chemotherapy+ intrathecal injection in 4 cases, surgery+ radiotherapy in 2 cases, and surgery alone in 3 cases.Until January 2020, the median survival time of all the 15 patients was 18 months (ranged 1-27 months), and the survival rate was 33.3%.The 1-year OS rate and PFS rate for all 15 cases were 71.5% and 49.7%, respectively.The 2-year OS rate and PFS rate were 17.9% and 0, respectively. Log- rank analyses revealed that the 1-year OS rates of children less than 3 years old and those older than 3 years were 87.5% and 57.1%, respectively ( χ2=6.057, P=0.014). The 1-year OS rates of children with GTR and those with STR were 90.0% and 40.0%, respectively ( χ2=6.057, P=0.014). The 1-year OS rates of children with tumor dissemination and those without tumor dissemination were 100.0% and 33.3%, respectively( χ2=9.865, P=0.002). The 1-year OS rates of children in the standard-risk group and those in the high-risk group were 88.9% and 41.7%, respectively ( χ2=5.111, P=0.024). COX regression analyses proved that age, the extent of tumor resection, tumor dissemination and risk stratification are independent risk factors for prognosis [hazard radio( HR)=3.411, 3.795, 5.245, 3.397; P=0.025, 0.011, 0.001, 0.017]. Conclusions:Pediatric intracranial AT/RT is rare.The preliminary diagnosis and prognosis are difficult and poor, respectively.The complete resection of tumors with maximal safety remains the primary treatment.Age, the extent of tumor resection, tumor dissemination and risk stratification are independent prognostic factors for AT/RT children.

Objective:To find the risk assessment model of [di (2-ethylhexyl) phthalate, DEHP] fitting well for producing companies.Methods:The Cluster Sampling method was used in selecting a DEHP producing company in the occupational health and workplace environment monitoring study conducted between July and August in 2017. Data was collected by site evaluating and workplace environment monitoring. According to GBZ/T 298-2017《Technical Guidelines for Occupational Health Risk Assessment of Chemical Hazards in the Workplace》, a qualitative assessment method and a semi-quantitative comprehensive index method were chosen as the models and were compared.Results:The occupational health risk of the two methods rated 4 (high risk) and 2 (negligible risk) .Conclusion:The semi-quantitative comprehensive index method is more comprehensive and accurate when used to assess the occupational health risk caused by DEHP.

Objective:To find the risk assessment model of [di (2-ethylhexyl) phthalate, DEHP] fitting well for producing companies.Methods:The Cluster Sampling method was used in selecting a DEHP producing company in the occupational health and workplace environment monitoring study conducted between July and August in 2017. Data was collected by site evaluating and workplace environment monitoring. According to GBZ/T 298-2017《Technical Guidelines for Occupational Health Risk Assessment of Chemical Hazards in the Workplace》, a qualitative assessment method and a semi-quantitative comprehensive index method were chosen as the models and were compared.Results:The occupational health risk of the two methods rated 4 (high risk) and 2 (negligible risk) .Conclusion:The semi-quantitative comprehensive index method is more comprehensive and accurate when used to assess the occupational health risk caused by DEHP.

Objective:To investigate the efficacy and safety of transurethral Moses holmium laser enucleation of the prostate (MoLEP) in the treatment of small-volume benign prostatic hyperplasia (BPH).Methods:The clinical data of 132 patients with small BPH (prostate volume <40 ml) who underwent MoLEP from October 2017 to April 2020 in the First Affiliated Hospital of Nanjing Medical University were analyzed retrospectively.The age of the patients was (63.93±5.21) years old, including 12 patients with cystolithiasis. The prostate volume of 132 patients was (32.16±7.81) ml, the preoperative international prostate symptom score (IPSS) was 23.00(15.00-34.00), the quality of life score (QOL) was 5(2-6), the maximum urinary flow rate (Q max) was 7.80(0.80-9.80)ml/s and residual urine volume (PVR) was 158(51-409) ml. 89 patients had the preoperative maximum detrusor contractility (64.23±8.11) cmH 2O. Surgical methods: the 120 W Moses laser platform(Lumenis Inc)was used, the cutting power was adjusted to 80 W (2.0J×40Hz) (narrow pulse width mode), and the hemostatic power 24W (0.8J×30Hz) (wide pulse width mode). Patients with bladder calcifications underwent Moses laser bladder stone lithotripsy.After the initial resection by the level of verumontanum was performed, an anatomic plane was exposed and carried forward until the bladder neck. If prostate stones were found, Moses holmium laser lithotripsy can be performed directly. After operation, the bladder was continuously flushed with normal saline. The catheter was removed 24 hours after the operation. The operation status, intraoperative and postoperative complications were recorded. IPSS, QOL, Q max and PVR were followed up 3 months after surgery. Postoperative urinary incontinence is defined as the need for 2 pads or more within 24 hours. Results:The operations of 132 cases (including 12 cases with bladder stones) were successfully completed. 30 cases with prostate calcifications were found during the operation. The operation time (enucleation time) was (16.83±4.03) min. There were no perioperative complications such as blood transfusion, transurethral resection syndrome, urinary retention and venous thromboembolism. No bladder neck contracture or recurrence of bladder stones was found after surgery. Postoperative urethral stricture occured in 2 cases (1.5%), and postoperative urinary incontinence in 27 cases (20.5%). There were 102 cases (77.3%) with chronic interstitial inflammatory cell infiltration. Three months after operation, IPSS was 7(0-14), QOL was 2(0-5), Q max was 17.55(9.40-26.50)ml/s and PVR was 27(0-46) ml, which were significantly improved compared with preoperatively( P<0.05). Conclusions:MoLEP can significantly improve lower urinary tract symptoms (LUTS) and life quality of patients with small-volume BPH.At the same time, the incidence of complications such as urethral stricture and urinary incontinence is lower. The operation is safe and reliable, and bladder stone lithotripsy can be performed at the same time.

Objective:To explore the clinical efficiency evaluation and prognostic factors of aspiration guided by neuronavigation in the treatment of pediatric brain abscess (PBA).Methods:A total of 47 patients with PBA were treated with aspiration guided by neuronavigation between January 2013 and January 2019 at the First Affiliated Hospital of Zhengzhou University.All clinical data were retrospectively analyzed.According to Glasgow Outcome Scale on discharge, all children were divided into 2 groups, namely good prognosis group and poor prognosis group.Prognostic factors were analyzed by using univariate analysis and binary Logistic regression multivariate analysis. Results:Among the 47 children, 38 children (80.9%) were assigned to the good prognosis group, and 9 children (19.1%) were assigned to the poor prognosis group.Univariate analysis proved that abscess volume>4 cm( χ2=5.650, P=0.017), multiple or multilocular abscess ( χ2=3.258, P=0.027), and abscess located in functional areas ( χ2=6.187, P=0.013) were correlated with poor prognosis.Multivariate analysis revealed that abscess volume>4 cm( OR=5.913, 95% CI: 2.241-25.917, P=0.023) and abscess located in functional areas ( OR=10.519, 95% CI: 3.918-62.513, P<0.001) were independent risk factors for poor prognosis. Conclusion:The treatment of PBA with aspiration guided by neuronavigation is safe, effective and minimal invasive, and the clinical efficiency is satisfactory.Abscess volume>4 cm and abscess located in deepbrain/functional areas are independent risk factors for poor prognosis.