3.00 and exposed to the solution containing 1500 mg/L peracetic acid for 30 min could completely killing the spores.Aerosol spraying with solution containing 1000 mg/L peracetic acid at a dose of 10 ml/m3 for 30 min caused over 90.0% decay rate of natural bacteria in indoor air.CONCLUSIONS Weikangshi peracetic acid has good stability and its germicidal efficacy is not affected.

Objective To realize the contamination status of dental unit waterlines (DUWL)in general hospitals, and provide scientific evidence for making preventive measures.Methods Three hospitals were selected for study, water source adopted by hospital A,B and C was running water,reservoir water,and filtered water through reverse osmosis filtration system respectively,specimens of dental handpiece spray water and flushing water of dental chair units were collected quarterly,total bacterial colony in water were detected.Results The qualified rate of source wa-ter,handpiece spray water,and flushing water in hospital A was 75.00%(3/4),0 (0/40)and 0 (0/40)respectively,col-ony count of handpiece spray water and flushing water was (1.20×103 -5.53×104 )CFU/mL(M=3.80×104 CFU/mL) and (2.11×104 -1.66×105 )CFU/mL(M=4.80×104 CFU/mL)respectively.The qualified rate of source water,hand-piece spray water,and flushing water in hospital B was 50.00%(2/4),60.00%(24/40)and 72.50%(29/40)respectively, colony count of handpiece spray water and flushing water was (0.00 -3.71 ×106 )CFU/mL(M=83.00 CFU/mL)and (0.00-2.39×106 )CFU/mL(M=72.00 CFU/mL)respectively.The qualified rate of source water,handpiece spray wa-ter,and flushing water in hospital C was 100.00%(4/4),55.00%(22/40)and 65.00%(26/40)respectively,colony count of handpiece spray water and flushing water was (0.00-6.20×103 )CFU/mL(M=96.00 CFU/mL)and(0.00-1.63×103 )CFU/mL(M=87.50 CFU/mL)respectively.Conclusion Water of DUWL in general hospitals is seriously con-taminated,disinfection and standardized management of source water and DUWL must be strengthened.

Objective To investigate whether ultrasonic coupling agent (UCA)can produce shielding or antago-nistic effect on iodine disinfectant for preoperative skin disinfection.Methods Shielding or antagonistic effect of UCA on iodine disinfectant were detected by laboratory carrier immersion killing test and on-the-spot skin disinfec-tion test.Results Antagonistic effect:after the mixing of iodophor with UCA,the average killing rate of iodophor containing available iodine 2 500mg/L and 625 mg/L to Staphylococcus aureus decreased from 100.00% to 99.67%-99.78% and 96.85 % - 98.25 %,respectively;the average killing rate to Escherichia coli decreased from 100.00% to 99.71 %-99.82% and 95 .93 %-98.56%,respectively.Shielding effect:after smearing with UCA, the average killing rate of iodophor and iodine tincture + alcohol to Escherichia coli decreased from 100.00% to 30.76% and 100.00% to 94.48%,respectively;the average killing rate to Staphylococcus aureus decreased from 99.99% to 55 .55 % and 100.00% to 98.22%,respectively.On-the-spot skin disinfection test:the killing rate of io-dophor and iodine tincture +alcohol to natural bacteria on skin surface were both 99.99%,after skin was smeared with UCA,the killing rate decreased to 92.62% and 93 .57%,respectively.Conclusion UCA remained on the oper-ative field has shielding and antagonistic effect on iodine disinfectant.

Objective: To investigate the effect of panax japlcus var polysaccharide (PJPS) on the proliferation and apoptosis of gastric cancer MKN45 cells and its regulatory mechanism. Methods: Human gastric cancer cell lines (HGC27, MGC803, MKN45) and gastric mucosal epithelial cell line GES-1 were selected for this study. Let-7a mimics and let-7a inhibitor were transfected into MKN45 cells; Gastric cancer cell lines were treated with 100 μg/ml PJPS and MKN45 was selected as the subsequent experimental cell line. MKN45 cells were cultured with 0, 10, 50, 100 and 120 μg/ml PJPS, respectively. The proliferation and apoptosis rate of MKN45 cells were detected by CCK-8 and flow cytometry, respectively. Expressions of cell cycle dependent kinase 6 (CDK6) and apoptosis-related proteins in MKN45 cells were detected by Western blotting, and the expression level of miRNAs regulating the proliferation of gastric cancer cells was detectedbyReal-timequantitativePCR(qPCR).TheDualluciferasereportergeneassaywasusedtovalidatethetargeting relationship between let-7a and CDK6. Results: Compared with other gastric cancer cells, 100 μg/ml PJPS significantly inhibited the proliferation of MKN45 cells (P<0.01). At the same time, 100 μg/ml PJPS significantly up-regulated the expression of let-7a in MKN45 cells (P<0.01). The Dual luciferase reporter gene assay confirmed that CDK6 was the target gene of let-7a. Furthermore, PJPS inhibited the expression of CDK6 by up-regulating let-7a, thereby inhibiting the proliferation and inducing apoptosis of MKN45 cells (all P<0.01). Conclusion: PJPS inhibits proliferation and induces apoptosis of gastric cancer MKN45 cells by regulating the let-7a/ CDK6 axis.

Objective:To explore the application and teaching effect of TSPV (short for theoretical teaching, simulated surgical skills training, practical surgery training, and video-based review) 4-step teaching in skill training of gynecologic laparoscopic surgery.Methods:A total of 30 trainees who participated in gynecologic laparoscopic surgery training were randomly divided into two groups, with 15 in each group. The experimental group received TSPV 4-step teaching, while the control group adopted traditional teaching and completed training and assessment in stages. The general data, training assessment results, teaching feedback and satisfaction survey of the two groups were compared and analyzed. SPSS 20.0 was used for t-test and Chi-square test. Results:There was no statistical difference in age, gender distribution, education background, clinical working experiences and other general data between the two groups. There was no significant difference in the theoretical examination scores between the two groups [(85.3±4.6) vs. (83.4±4.3), P=0.252]. The scores of simulated operation assessment [(91.7±5.2) vs. [(72.4±5.9), P<0.001] and clinical practice assessment [(88.5±4.8) vs. (82.7±6.7), P=0.011] in the experimental group were better that those in the control group. In addition, the experimental group had a better overall evaluation of teaching satisfaction. Conclusion:TSPV 4-step teaching is a more optimized and popular gynecologic laparoscopic training mode, which is recommended to further promote the validation in teaching.

Objective To investigate the correlations among homocysteine(Hcy)level,serum cystatin C (Cys-c)and diabetic peripheral neuropathy(DPN).Methods Two hundred and three diagnosed cases of type 2 diabetes were enrolled,including 123 DPN patients(DPN+)and 80 non-DPN(DPN-)patients.Levels of serum Hcy,Cys-c,high-sensitivity C-reactive protein(hs-CRP)and fiber fibrinogen(Fg)were detected.The above indi-cators and the baseline data such as sex,age,duration,BMI,WHR,HOMA-IR(CP),HOMA-islet(CP)were statistically analyzed. Results Hcy,Cys-c,and the duration of the DPN+ group were significantly higher than those in the DPN-group(P<0.05,respectively).HOMA-islet(CP)in the DPN-group was markedly higher than that in the DPN+group(P<0.01).The prevalence of DPN in the high level of Hcy group was much higher than that in the low and the normal level of Hcy group.Hcy was still significantly correlated with the Cys-c after taking the controlled procedure such as duration and fibrinogen. Conclusion High levels of Hcy and Cys-c are the criti-cal risk factors of DPN,collaborative determination of Hcy and Cys-c level might be of quitevaluable in early diag-nosis of DPN.

Understanding of the nephrotoxicity induced by drug candidates is vital to drug discovery and development. Herein, an metabolomics method based on air flow-assisted desorption electrospray ionization mass spectrometry imaging (AFADESI-MSI) was established for direct analysis of metabolites in renal tissue sections. This method was subsequently applied to investigate spatially resolved metabolic profile changes in rat kidney after the administration of aristolochic acid I, a known nephrotoxic drug, aimed to discover metabolites associated with nephrotoxicity. As a result, 38 metabolites related to the arginine-creatinine metabolic pathway, the urea cycle, the serine synthesis pathway, metabolism of lipids, choline, histamine, lysine, and adenosine triphosphate were significantly changed in the group treated with aristolochic acid I. These metabolites exhibited a unique distribution in rat kidney and a good spatial match with histopathological renal lesions. This study provides new insights into the mechanisms underlying aristolochic acids nephrotoxicity and demonstrates that AFADESI-MSI-based metabolomics is a promising technique for investigation of the molecular mechanism of drug toxicity.

Detailed knowledge on tissue-specific metabolic reprogramming in diabetic nephropathy (DN) is vital for more accurate understanding the molecular pathological signature and developing novel therapeutic strategies. In the present study, a spatial-resolved metabolomics approach based on air flow-assisted desorption electrospray ionization (AFADESI) and matrix-assisted laser desorption ionization (MALDI) integrated mass spectrometry imaging (MSI) was proposed to investigate tissue-specific metabolic alterations in the kidneys of high-fat diet-fed and streptozotocin (STZ)-treated DN rats and the therapeutic effect of astragaloside IV, a potential anti-diabetic drug, against DN. As a result, a wide range of functional metabolites including sugars, amino acids, nucleotides and their derivatives, fatty acids, phospholipids, sphingolipids, glycerides, carnitine and its derivatives, vitamins, peptides, and metal ions associated with DN were identified and their unique distribution patterns in the rat kidney were visualized with high chemical specificity and high spatial resolution. These region-specific metabolic disturbances were ameliorated by repeated oral administration of astragaloside IV (100 mg/kg) for 12 weeks. This study provided more comprehensive and detailed information about the tissue-specific metabolic reprogramming and molecular pathological signature in the kidney of diabetic rats. These findings highlighted the promising potential of AFADESI and MALDI integrated MSI based metabolomics approach for application in metabolic kidney diseases.