[摘 要] 目的：研究芳香烃受体（AHR）在乳腺癌中的表达及其对乳腺癌细胞增殖、凋亡和药物敏感性的调控机制。方法：通过GEPIA数据库数据分析乳腺癌组织及癌旁组织中AHR的表达水平，探讨其与患者生存期的关联。利用基因敲低和过表达技术构建AHR表达变化的乳腺癌细胞，采用CCK-8实验、细胞计数和流式细胞分析等方法评估AHR对细胞增殖、凋亡和药物敏感性的影响，通过免疫印迹法验证相关分子机制。此外，利用AHR激动剂6-甲酰基吲哚并[3,2-B]咔唑（FICZ）研究外源性激活AHR对乳腺癌细胞多柔比星（DOX）敏感性的影响。结果：GEPIA数据库数据分析结果显示，乳腺癌组织中AHR呈明显低表达（P < 0.05）；对155例乳腺癌患者的生存期进行统计分析也显示AHR低表达与不良预后呈正相关（P < 0.05）。敲低AHR促进细胞增殖（P < 0.05），过表达则能抑制其增殖（P < 0.05）并促进其凋亡（P < 0.05）。外源激活AHR能增强乳腺癌细胞对DOX的敏感性（P < 0.05）。AHR可与MYC基因启动子结合，抑制MYC表达（P < 0.05），从而影响乳腺癌的进展。结论：AHR在乳腺癌中通过调控MYC表达影响细胞增殖和凋亡，外源激活AHR可能成为提高乳腺癌细胞对DOX敏感性的治疗策略。

Background: Twenty-four-hour urinary free cortisol (UFC) measurement is the initial diagnostic test for Cushing’s syndrome (CS). We compared UFC determination by both direct and extraction immunoassays using Abbott Architect, Siemens Atellica Solution, and Beckman DxI800 with liquid chromatography-tandem mass spectrometry (LC-MS/MS). In addition, we evaluated the value of 24-hr UFC measured by six methods for diagnosing CS. Methods: Residual 24-hr urine samples of 94 CS and 246 non-CS patients were collected.A laboratory-developed LC-MS/MS method was used as reference. UFC was measured by direct assays (D) using Abbott, Siemens, and Beckman platforms and by extraction assays (E) using Siemens and Beckman platforms. Method was compared using Passing–Bablok regression and Bland–Altman plot analyses. Cut-off values for the six assays and corresponding sensitivities and specificities were calculated by ROC analysis. Results: Abbott-D, Beckman-E, Siemens-E, and Siemens-D showed strong correlations with LC-MS/MS (Spearman coefficient r = 0.965, 0.922, 0.922, and 0.897, respectively), while Beckman-D showed weaker correlation (r = 0.755). All immunoassays showed proportionally positive bias. The areas under the curve were 0.975 for Abbott-D, 0.972 for LCMS/MS, 0.966 for Siemens-E, 0.948 for Siemens-D, 0.955 for Beckman-E, and 0.877 for Beckman-D. The cut-off values varied significantly (154.8–1,321.5 nmol/24 hrs). Assay sensitivity and specificity ranged from 76.1% to 93.2% and from 93.0% to 97.1%, respectively. Conclusions Commercially available immunoassays for measuring UFC show different levels of analytical consistency compared to LC-MS/MS. Abbott-D, Siemens-E, and Beckman-E have high diagnostic accuracy for CS.

Umbilical cord mesenchymal stem cells (UC-MSCs) have been widely used in regenerative medicine, but there is limited research on the stability of UC-MSCs formulation during production. This study aims to assess the stability of the cell stock solution and intermediate product throughout the production process, as well as the final product following reconstitution, in order to offer guidance for the manufacturing process and serve as a reference for formulation reconstitution methods. Three batches of cell formulation were produced and stored under low temperature (2-8 ℃) and room temperature (20-26 ℃) during cell stock solution and intermediate product stages. The storage time intervals for cell stock solution were 0, 2, 4, and 6 h, while for intermediate products, the intervals were 0, 1, 2, and 3 h. The evaluation items included visual inspection, viable cell concentration, cell viability, cell surface markers, lymphocyte proliferation inhibition rate, and sterility. Additionally, dilution and culture stability studies were performed after reconstitution of the cell product. The reconstitution diluents included 0.9% sodium chloride injection, 0.9% sodium chloride injection + 1% human serum albumin, and 0.9% sodium chloride injection + 2% human serum albumin, with dilution ratios of 10-fold and 40-fold. The storage time intervals after dilution were 0, 1, 2, 3, and 4 h. The reconstitution culture media included DMEM medium, DMEM + 2% platelet lysate, 0.9% sodium chloride injection, and 0.9% sodium chloride injection + 1% human serum albumin, and the culture duration was 24 h. The evaluation items were viable cell concentration and cell viability. The results showed that the cell stock solution remained stable for up to 6 h under both low temperature (2-8 ℃) and room temperature (20-26 ℃) conditions, while the intermediate product remained stable for up to 3 h under the same conditions. After formulation reconstitution, using sodium chloride injection diluted with 1% or 2% human serum albumin maintained a viability of over 80% within 4 h. It was observed that different dilution factors had an impact on cell viability. After formulation reconstitution, cultivation in medium with 2% platelet lysate resulted in a cell viability of over 80% after 24 h. In conclusion, the stability of cell stock solution within 6 h and intermediate product within 3 h meets the requirements. The addition of 1% or 2% human serum albumin in the reconstitution diluent can better protect the post-reconstitution cell viability.

Objective To design a medical order pre-evaluation tool for perioperative prophylactic application of antibiotics,and to improve the efficiency of antibiotics management in hospitals during the perioperative period.Methods Using the open-source software R as the platform,a web application was built with tidy verse and shiny package based on related documents and guidelines.The discharge records of Affiliated Hospital of North Sichuan Medical College from April 1,2021,to December 31,2022,were retrospectively reviewed using the constructed pre-evaluation tool and compared with previous manual evaluation results using McNemar's Chi-squared test.Results This medical order pre-evaluation tool can quickly complete perioperative antibiotics order sampling,batch pre-evaluation,result statistics,visualization,and result output,and flexibly adjust the evaluation rules according to actual needs.The pre-evaluation tool is more efficient,with a review speed of 13.46 ms per medical record.Among the 2 642 discharge medical records of manual review,there was no significant difference between systematic pre-evaluation and manual evaluation results(ratio of prophylactic use:76.85%vs.78.21%)in terms of the type of use(preventive or curative)(P= 0.078).Among the 1 857 discharge records judged to be prophylactic for both manual and systematic reviews,the difference in unreasonable detection rate(39.90%vs.30.32%)was statistically significant(P＜0.001).Among the 63 typical ludicrous medical records confirmed by the review of clinical pharmacists with senior professional titles,60 were judged and limited by the pre-evaluation tool,and the detection rate of typical unreasonable was 95.24%.Conclusions The pre-evaluation tool based on R in this study can improve the efficiency of perioperative antibacterial drug evaluation.The evaluation conclusions and statistical results are reliable and are worthy of further development and application.

AIM:To test and compare the perceptual eye position and fixation stability of adolescents with emmetropia and adolescents with low myopia, investigating the characteristics of the perceptual eye position and fixation stability of adolescents with low myopia.METHODS: Cross-sectional study. A total of 132 adolescents(264 eyes)who visited in the ophthalmology clinic of our hospital from April to December 2023 were randomly selected as the research subjects. Participants were categorized into normal control group(n=45, 90 eyes), simple low myopia group(n=45, 90 eyes)and low myopia with anisometropia group(n=42, 84 eyes)according to their refractive status and were underwent assessments for perceptual eye position and fixation stability.RESULTS: Compared with the normal control group, the static and dynamic horizontal perceptual eye position deviation of the simple low myopia group and the low myopia with anisometropia group were significantly increased(P<0.05). Compared with the simple low myopia group, the static and dynamic horizontal perceptual eye position deviation of the low myopia with anisometropia group were significantly increased(P<0.05). There was no significant difference in static and dynamic vertical perceptual eye position deviation among the three groups(P>0.05); compared with the normal control group, the horizontal and vertical fixation stability of the simple low myopia group and the low myopia with anisometropia group were significantly worse(all P<0.01), but there was no differences in the simple low myopia group and the low myopia with anisometropia group(P >0.05).CONCLUSION: Abnormalities are observed in perceptual eye position and fixation stability function in adolescents with low myopia compared with those adolescents with emmetropia, even at best corrected visual acuity. The occurrence of anisometropia could lead to an increased degree of horizontal perceptual eye position displacement.

Aim To investigate the role of metabolites of eicosapentaenoic acid (EPA) in promoting the transdifferentiation of pancreatic α cells to β cells. Methods Male C57BL/6J mice were injected intraperitoneally with 60 mg/kg streptozocin (STZ) for five consecutive days to establish a type 1 diabetes (T1DM) mouse model. After two weeks, they were randomly divided into model groups and 97% EPA diet intervention group, 75% fish oil (50% EPA +25% DHA) diet intervention group, and random blood glucose was detected every week; after the model expired, the regeneration of pancreatic β cells in mouse pancreas was observed by immunofluorescence staining. The islets of mice (obtained by crossing GCG

Aim To express and purify recombinant hCGH-CTP fusion protein in high-density suspension culture of Chinese hamster ovary cells (CHO-S), and to verify the lipid accumulation effect of rhCGH-CTP on 3T3-L1 mature adipocytes. Methods The recombinant protein expression vector (pcDNA3. 1-rhCGH-CTP) was constructed, achieved by fusing the human glycoprotein hormone beta 5/alpha 2 cDNA with CTP Linker. The expression plasmid was transiently transfected into the suspended CHO-S to express rhCGH-CTP protein and then purified, and the protein biological activity was verified. Intervention with 3T3-L1 mature adipocyte cells for 24 h was performed to detect the changes of intracellular triglyceride (TG) level. Results Western blot results showed that rhCGH-CTP protein was successfully expressed in CHO-S cells, and the yield was up to 715. 4 mg • L~ . The secreted protein was purified by AKTA pure system with higher purity that was up to 90% as identified by SDS-PAGE. In addition, the intracellular cAMP content of mature adipocytes with high expression of TSHR gene significantly increased after intervention with different concentrations of rhCGH-CTP protein by ELISA kit, indicating that rhCGH-CTP protein had biological activity. Oil red 0 staining showed that compared with the control group, the lipid content of mature adipocytes in the intervention groups with different concentrations of rhCGH-CTP protein significantly decreased (P < 0. 05) . Conclusions The rhCGH-CTP protein has been successfully expressed and purified with biological activity, and effectively reduce TG. This research provides an important theoretical basis for further revealing the physiological role of CGH protein and its potential application in clinical practice.

Objective The causes of bleeding after endoscopic duodenal papilloma resection were analyzed and discussed,and the prediction model of nomogram was established.Methods A total of 233 patients who underwent endoscopic duodenal papilloma resection in our hospital from January 2018 to December 2023 were retrospectively analyzed,and they were divided into bleeding group(n=31 cases)and non-bleeding group(n=202 cases)according to whether postoperative bleeding occurred.The clinical data of the two groups were compared,the independent risk factors for postoperative bleeding were analyzed by multi-factor logistic regression,the risk nomogram prediction model was constructed,and the Bootstrap method was used for 1000 repeated samples to carry out internal verification.Results Anticoagulant drugs(OR=9.063,95％CI:2.132-38.525),lesion diameter ≥2 cm(OR=2.802,95％CI:1.073-7.321),intraoperative fragment resection(OR=27.653,95％CI:3.055～619.174)and pancreatic complications(OR=6.859,95％CI:1.930～24.377)were independent risk factors for postoperative bleeding after endoscopic duodenal papilloma resection(P＜0.05).A risk prediction nomogram model was constructed according to the Logistic regression analysis results.The samples were repeatedly sampled 1000 times through Bootstrap method for internal verification.The area under the ROC curve was 0.850,and the 95％CI was 0.780-0.913,indicating good differentiation ability of the model.Calibration curve analysis indicated that the prediction probability of postoperative bleeding predicted by the nomogram prediction model was in good agreement with the actual probability of postoperative bleeding,and Hosmer-Lemeshow showed good goodness of fit(x2=3.304 9,P=0.913 8).Conclusion Taking anticoagulant drugs,lesion diameter ≥2 cm,intraoperative segmentary resection,and postoperative combination of pancreas were independent risk factors for bleeding after endoscopic duodenal papilloma resection.A nomogram prediction model was established to help clinical assessment of postoperative bleeding risk in patients and improve decision-making basis for early prevention.

Objective:To design a virtual simulation tutorial system for bone traction nursing of the lower limbs, and to investigate its application effect.Methods:Based on clinical cases, a 3D model was established for the fractured lower limb using the virtual simulation technique. The design of the model considered the position and mechanical relationship between bone traction and fracture ends, as well as the assessment and intervention of the condition after bone traction, and such factors were taken as the core elements of simulation design. Virtual experiments were conducted for the four scenarios of pre-hospital first aid, triage in the hospital, bone traction operation, and postoperative nursing. Such experiments were conducted among junior nursing undergraduates, and examination results and student satisfaction survey were used to evaluate the application effect of the experiments.Results:The teaching software consisted of four training modules, i.e., theoretical knowledge learning of fractures, preparation before bone traction operation, methods and principles of bone traction operation, and observation of conditions after bone traction. The final score of experiments was (90.99±0.58) points among the students, and the degree of satisfaction with the experimental system and the teaching model was 87.85% (441/502) and 63.35% (318/502), respectively.Conclusions:The virtual simulation experiments for bone traction nursing of the lower limbs are scientific, professional, and interesting and have a relatively high degree of satisfaction among students, and therefore, they can be applied in the education of nursing students and the continuing education of nurses.

Neuregulin 4 (NRG4) is a newly discovered adipokine,which plays crucial roles in many physiological processes such as energy balance,and glucose and lipid metabolism.The transcriptional regulation of NRG4 gene remains largely unknown.Our previous 5'RACE analysis showed that the tran-scription start sites (TSS) of chicken NRG4 gene were dispersed over a region of 200 bp,suggesting that chicken NRG4 gene possesses a dispersed promoter.In the present study,the promoter activity of the proximal exon and intron of chicken NRG4 gene was analyzed.Dual-luciferase reporter assay demonstra-ted that the genomic fragment (-122/+452) containing exon 1,intron 1,and exon 2 of chicken NRG4 gene had strong bidirectional promoter activity.Bioinformatics analysis showed that there was a putative binding site of the transcription factor CCAAT enhancer-binding proteinα(C/EBPα) in exon 2 of chick-en NRG4 gene.Reporter gene assay showed that both deletion and site-directed mutagenesis of the C/EBPα binding site abrogated the regulatory effect of C/EBPα on the promoter activity of the-122/+452 fragment of chicken NRG4 gene.Gene expression correlation analysis showed that C/EBPα and NRG4 gene expression were positively correlated in chicken adipose tissues.ChIP-PCR revealed that C/EBPα directly binds to the exon 2 of NRG4 gene in chicken adipose.In conclusion,the proximal exon and intron of chicken NRG4 gene has bidirectional promoter activity,and C/EBPα directly regulates NRG4 gene expression in chicken adipose via binding to its exon 2.