Objective To establish a classification tree model for non-alcoholic fatty liver disease(NAFLD)among aircrews,screen for influencing factors of NAFLD,so as to provide scientific basis for prevention and intervention decisions for NAFLD.Methods Aircrews who underwent recuperation at a sanatorium from January 2019 to December 2023 were selected as the research objects.Their annual physical examination data were collected and the NAFLD detection rate was calculated.Age,body mass index(BMI),blood pressure,waist circumference,blood routine,biochemistry indexes,and thyroid function were incorporated,and a NAFLD risk model was constructed using classification regression tree method.The predictive performance of the NAFLD classification tree model was evaluated through model misclassification matrix,risk statistics,and receiver operating characteristic curve.Results A total of 4088 aircrews were included in the study,and NAFLD was detected in 380 persons(380/4088,9.30%).The NAFLD model consisted of three layers,and five explanatory variables affecting the onset of NAFLD were extracted,including BMI,triglycerides(TG),high-density lipoprotein cholesterol(HDL-C),alanine aminotransferase(ALT),and total bilirubin(TBIL).BMI was located at the top of the classification tree and was the most important risk factor for NAFLD in aircrews.The area under the curve(AUC)of the model was 0.853.The predictive accuracy of NAFLD was 90.9%,indicating that the model has good accuracy and fitting effect.Conclusion In this study,the detection rate of NAFLD in aircrews was 9.30%.BMI,TG,HDL-C,ALT,and TBIL are risk factors for the onset of NAFLD.NAFLD is mainly related to weight gain and lipid metabolism disorders caused by unhealthy lifestyles.

Objective To analyze the expression characteristics of excision repair cross-complementing 1 (ERCC1), topoisomeraseⅡ (TOPOⅡ), ribonucleotide reductase M1 (RRM1), β3-tubulin and thymidylate synthase (TS) in lung cancer and their associations with the pathological types. Methods The immunohistochemical EnVision method was used to determine the expression of ERCC1, TOPOⅡ, RRM1,β3-tubulin and TS in 548 patients who were diagnosed as lung cancer from January 2011 to December 2014. Variance analysis was performed to analyze their expression characteristics among different pathological types and correlation. Results The expression positive rates of ERCC1, TOPOⅡ, RRM1, β3-tubulin and TS were 61.86 % (339/548), 91.06 % (499/548), 62.59 % (343/548), 73.18 % (401/548) and 70.44 % (386/548), respectively. The expression of ERCC1 was weak positive mostly (P<0.05), meanwhile the expression of TOPOⅡ was medium-strong positive mostly (P<0.05). In ERCC1 group, the positive rate of squamous cell carcinoma was higher than that of adenocarcinoma [57.39 % (167/291) vs. 42.61 % (124/291), P=0.000]. In weak positive of TOPOⅡ group, the proportion of adenocarcinoma was higher than that of squamous cell carcinoma [23.58 % (100/137) vs. 8.73 % (37/137), P=0.000]. In medium-strong positive of TOPOⅡ group, the proportion of squamous cell carcinoma was higher than that of adenocarcinoma [47.41 % (201/287/) vs. 20.28%(86/287), P=0.000]. The expressions of ERCC1, TOPOⅡ, RRM1,β3-tubulin and TS were irrelevant (r=0.4, P=0.397). Conclusions The expressions of ERCC1 and TOPOⅡ are higher in squamous cell carcinoma than those in adenocarcinoma. The expression of ERCC1 is weak positive mostly, meanwhile the expression of TOPOⅡis medium-strong positive mostly. There is no correlation between them.

Objective To investigate the therapeutic effect of quercetin on acute gouty arthritis and its influence in re-nal function in rats. Methods Seventy male Sprague-Dawley rats were randomly divided into normal control group, model group, colchicine group (0.5 mg/kg), allopurinol group (20 mg/kg), quercetin 100, 200 and 400 mg/kg groups (n=10 for each group). Rats were administered various drugs by oral gavage once a day for seven consecutive days throughout the experi-ment. On the fifth day, the animal model of acute arthritis was set up by giving monosodium urate crystal combined with hypo-xanthine. The inflammatory reaction was detected by measuring the circumference of right hind leg anklejoint with a tie line method at 0, 2, 6, 12, 24 and 48 h. The swelling ratio was calculated. The serum levels of uric acid (UA),β2-microglobulin (β2-MG), cystatin C (Cys-C), urea nitrogen (Urea) and creatinine (Cr) were detected by colorimetry and enzyme-linked im-munosorbent assay.Rats were sacrificed at the end of experiment, and the kidney was weighed and the renal index was calcu-lated. Results Treatment with quercetin, colchicine or allopurinol can significantly attenuate swelling rate in rats of acute gouty arthritis. The serum levels of UA were significantly higher in colchicine group and quercetin group than those of nor-mal control group and allopurinol group. The serum levels of UA was significantly lower in allopurinol group than that of nor-mal control group. After 48-h modeling, there was no significant difference in serum UA level between seven groups except allopurinol group. The levels ofβ2-MG and Cys-C were the lowest in normal control group than those of other groups. The se-rum levels of Urea and Cr and renal index were the highest in allopurinol group compared with those of other groups ( P<0.05). Conclusion Quercetin shows a significant effect of anti-inflammatory on acute gouty arthritis in rats. The model es-tablishment may lead to different degrees of renal damage. Quercetin has no protective effect against renal injury, and allopu-rinol aggravates kidney injury.