ObjectiveTo investigate the protective effect of the extract of Liuwei Dihuangwan （LW） on mitochondrial damage in the Alzheimer's disease （AD） model of Caenorhabditis elegans （C. elegans）. MethodC. elegans transfected with human β-amyloid protein （Aβ） _1-42 gene was used as an AD model. The rats were divided into blank group， model group， metformin group （50 mmol·L^-1）， and low， medium， and high dose （1.04， 2.08， 4.16 g·kg^-1） LW groups. Behavioral methods were used to observe the sensitivity of 5-hydroxytryptamine （5-HT） in nematodes. Western blot was used to detect the expression of Aβ in nematodes. Total ATP content in nematodes was detected by the adenine nucleoside triphosphate （ATP） kit， and mitochondrial membrane potential was detected by the JC-1 method. In addition， the mRNA expression of Aβ expression gene （Amy-1）， superoxide dismutase-1 （SOD-1）， mitochondrial transcription factor A homologous gene-5 （HMG-5）， mitochondrial power-associated protein 1 （DRP1）， and mitochondrial mitoprotein 1 （FIS1） was detected by real-time fluorescence quantitative polymerase chain reaction （RT-PCR）. ResultThe extract of LW could reduce the hypersensitivity of the AD model of nematodes to exogenous 5-HT （P<0.05） and delay the AD-like pathological characteristics of hypersensitivity to exogenous 5-HT caused by toxicity from overexpression of Aβ in neurons of the AD model of nematodes. Compared with the blank group， in the model group， the mRNA expression of Aβ protein and Amy-1 increased （P<0.01）， and the mRNA expression of SOD-1 and HMG-5 decreased （P<0.01）. The mRNA expression of DRP1 and FIS1 increased （P<0.01）， and the level of mitochondrial membrane potential decreased （P<0.05）. The content of ATP decreased （P<0.01）. Compared with the model group， in the positive medicine group and medium and high dose LW groups， the mRNA expression of Aβ protein and Amy-1 decreased （P<0.05，P<0.01）， and the mRNA expression of SOD-1 and HMG-5 increased （P<0.01）. The mRNA expression of DRP1 decreased （P<0.05，P<0.01）， and that of FIS1 decreased （P<0.01）. The level of mitochondrial membrane potential increased （P<0.01）， and the content of ATP increased （P<0.05，P<0.01）. ConclusionThe extract of LW may enhance the antioxidant ability of mitochondria， protect mitochondrial DNA， reduce the fragmentation of mitochondrial division， repair the damaged mitochondria， adjust the mitochondrial membrane potential， restore the level of neuronal ATP， and reduce the neuronal damage caused by Aβ deposition.

Pseudorabies virus(PRV)is the etiological agent of pseudorabies in pigs,which is char-acterized by dyspnea,reproductive disorders,and neurological diseases,and it spreads widely a-round the world.Since 2011,the newly emerged PRV variants have resulted in poor immunity pro-tection of traditional vaccine strains,and the original method of vaccine strain preparation is time-consuming and labor-intensive.Therefore,it is urgently needed to develop an efficient screening method of the vaccine strain at present.Using CRISPR/Cas9 gene editing technology in this study,two single guide RNAs(sgRNA)were designed targeting the virulence gene TK of PRV variant strain CH/JX/2016,and then the enhanced green fluorescent protein the reporter(EGFP)gene was inserted at the TK locus by a homologous repair plasmid.After multiple rounds of plaque puri-fication,the rPRV-ΔTK/EGFP strain was obtained.The results showed the cleavage efficiency of the two sgRNAs was extremely high.The preparation of rPRV-ΔTK/EGFP strain was succeed af-ter only three rounds of purification,and the EGFP expressed normally.The CRISPR/Cas9 system can edit the PRV gene simply,rapidly,and efficiently,and exhibits great potential in the construction of vaccine candidate strains.Meanwhile,the rescued rPRV-ΔTK/EGFP strain not only could be used as a tracer strain in PRV variant infection progresses,but also for subsequent antivi-ral drug screening.

Objective:To analyze the correlation of poorly differentiated cluster(PDC)grade with clinicopathological features and prognosis of patients with colon cancer.Methods:Hematoxylin-eosin-stained specimens and data from 102 patients with colon cancer who under-went surgery at the Affiliated Hospital of Anhui West Health Vocational College between December 2016 and July 2021 were analyzed in this study.The PDC grades of tumor tissues were determined in all colon cancer cases.Additionally,associations between the PDC grade and clinicopathological features of patients were analyzed via Chi-square test and Logistic regression analysis,whereas the association between the PDC grade and patient prognosis was evaluated using Cox regression analysis.Results:In total,52 cases were identified as PDC G1,14 as PDC G2,and 36 as PDC G3.Tumor budding(TB)was independently and positively associated with PDC,whereas tumor infiltrating lympho-cytes(TIL)were independently and negatively associated with PDC(all P<0.05).Lymph node metastasis or presence of cancerous nodules(hazard ratio[HR]=2.377;95%confidence interval[CI]=1.237-4.568;P=0.009),distant metastasis(HR=7.455;95%CI=2.597-21.399;P<0.001),and the PDC grade(HR=2.095;95%CI=1.099-3.994;P=0.025)were independent risk factors for colon cancer progression.Conclu-sions:Our findings suggest that both TIL and TB affect the colon cancer PDC grade.Therefore,evaluating the PDC grade in cancer tissues can facilitate the prognostic stratification of patients with colon cancer.

Objective: To investigate the role and mechanism of Sigirr deletion in chronic kidney disease complicated with renal interstitial fibrosis (CKD⁃RIF) in mice. Methods: polymerase chain reaction (PCR) was used for identification of gene types of mice. Mice were continuously fed with the foods containing 0. 2% adenine for 12 weeks to establish the CKD⁃RIF models. Then , serum was collected to detect levels of creatinine and nitrogen when mice were killed. H&E staining was used to analyze the pathological changes of kidney tissues. Masson staining was used to observe the degree of renal fibrosis. Immunohistochemistry was used to detect the changes of the interest proteins , such as IL⁃1β , MyD88 , activated NF⁃κB , TGF⁃ β1 , E ⁃cadherin and Vimentin. Results: Serum creatinines and urea nitrogens of mice fed with high adenine (CKD⁃RIF groups) significantly increased , compared with those of the control groups. H&E and Masson staining results showed that there were more infiltrated inflammatory cells and more critical collagen fiber deposition in the renal tissues of the Sigirr - / - mice with CKD⁃RIF. Western blot and Immunohistochemical analysis showed that the expression of IL⁃1β and its downstream MyD88 increased , and the level of phosphorylated NF⁃κB (p⁃P65) significantly increased in the renal tissues of CKD⁃RIF mice compared with the controls. And upregulation of these proteins in renal tissues of Sigirr - / - mice with CKD⁃RIF was more obvious than that of the CKD⁃RIF Sigirr + / + mice. TGF⁃ β1 , as a key cytokine involved in renal interstitial fibrosis , significantly increased ,followed by the increase of vimentin , as well as the decrease of E ⁃cadherin . The results of vimentin and cadherin E detected by Western blot were consistent with those of immunohistochemistry , and α ⁃SMA also increased significantly. Conclusion Adenine diet successfully induces CKD⁃RIF mice models. Sigirr deletion is beneficial to activation of the IL⁃1β mediating NF⁃κB signal pathway ,which promotes TGF⁃ β1 expression in the renal interstitiums to induce renal interstitial fibrosis.

Objective     To explore the clinical efficacy and learning curve of robot-assisted thymectomy via subxiphoid approach. Methods    The clinical data of patients with robot-assisted thymectomy surgery via subxiphoid approach performed by the same surgical team in the Department of Thoracic Surgery of Shanghai Pulmonary Hospital from February 2021 to August 2022 were retrospectively analyzed. The cumulative sum (CUSUM) analysis and best fit curve were used to analyze the learning curve of this surgery. The general information and perioperative indicators of patients at different learning stages were compared to explore the impact of different learning stages on clinical efficacy of patients. Results    A total of 67 patients were enrolled, including 31 males and 36 females, aged 57.10 (54.60, 59.60) years. The operation time was 117.00 (87.00, 150.00) min. The best fitting equation of CUSUM learning curve was y=0.021 2x3–3.192 5x2 +120.17x–84.444 (x was the number of surgical cases), which had a high R2 value of 0.977 8, and the fitting curve reached the top at the 25th case. Based on this, the learning curve was divided into a learning period and a proficiency period. The operation time and intraoperative blood loss in the proficiency stage were significantly shorter or less than those in the learning stage (P<0.001), and there was no statistical difference in thoracic drainage time and volume between the two stages (P>0.05). Conclusion    The learning process of robot-assisted thymectomy via subxiphoid approach is safe, and this technique can be skillfully mastered after 25 cases.

Objective:To study the effect of total flavonoids of Rhizoma Drynariae on learning and memory impairment mice induced by sodium nitrite. Methods:75 mice were divided into blank group, model group, Kangnaoshuai capsule group, Rhizoma Drynariae total flavonoids group and Rhizoma Drynariae total flavonoids+inhibitor group according to the random number table method, with 15 mice in each group. The Kangnaoshui Capsule group was administered with Kangnaoshui Capsule 585 mg/kg, the Rhizoma Drynariae total flavonoids group was administered with the Rhizoma Drynariae total flavonoids 97.5 mg/kg, the Rhizoma Drynariae total flavonoids group and the inhibitor group were administered with the Rhizoma Drynariae total flavonoids by intragastric administration 97.5 mg/kg, and intraperitoneal injection of 0.072 mg/kg ICI182780 for 21 days, once a day. The model was established on the 22nd day. Except for the blank group, the other mice were injected with sodium nitrite intraperitoneally to replicate the mice model with impaired learning and memory capability. The learning and memory capabilit of mice were detected with water maze method, and the estrogen receptor in hippocampus was detected by immunohistochemistry β (estrogen receptor β, ERβ). The expression of ERβ in hippocampus and the expression of phosphorylated P38 (P-P38) and the protein contents of B-cell lymphoma-2 (Bcl-2), Bcl-2 associated death promoter (Bad) and Caspase-3 in the apoptotic system was detected by Western blot. The kit was used to detect MDA,SOD and NO protein content in hippocampus. Results:The latency of Rhizoma Drynariae total flavonoids group was significantly shorter than the model group, the number of crossing platform and the residence time in the target quadrant were significantly increased ( P<0.01); The expression of ERβ Protein in mice hippocampus (0.371 ± 0.010 vs. 0.124 ± 0.009), Bcl-2 protein (1.146 ± 0.028 vs. 0.726 ± 0.016) and the contents of SOD [(153.657 ± 6.385) U/mg vs. (67.719±5.845) U/mg] increased significantly ( P<0.01); The expression of P-P38/P38 protein (0.412 ± 0.043 vs.0.806 ± 0.069), Bad protein (0.421 ± 0.010 vs.0.633 ± 0.010), Caspase-3 protein (0.923 ± 0.042 vs.1.437 ± 0.033), and the content of MDA [(8.669 ± 0.662) nmol/mg vs. (11.772 ± 1.054) nmol/mg] and NO [(4.259 ± 0.225) nmol/mg vs. (10.805 ± 0.415) nmol/mg] decreased significantly ( P<0.01). In addition, ER blocker can antagonize the above recovery and improvement effects of Rhizoma Drynariae total flavonoids group. Conclusion:Rhizoma Drynariae total flavonoids can regulate memory impairment, inhibit neuronal apoptosis and reduce oxidative stress in sodium nitrite model mice through ER-P38/MAPK signal pathway.

Objective:To assess the reliability, constructive validity and item characteristics of the general self-efficacy scale (GSES) among Chinese medical postgraduates using classical test theory and item response theory.Methods:A questionnaire survey was conducted among 1 021 medical postgraduates from 6 comprehensive level Ⅲ A hospitals in Beijing. Demographic characteristics and general self-efficacy were investigated. SPSS 24.0 software was used for statistical analysis. Internal consistency of the GSES was evaluated using Cronbach’s α coefficient and intraclass correlation coefficient. Factor analyses were implemented to test the structure of the scale. An item response theory (IRT) framework with a graded response model was performed to estimate the parameters of each item. Results:The overall Cronbach’s α coefficient of the GSES was 0.92. Parallel analysis and confirmatory factor analysis supported the unidimensional structure of the GSES. The discrimination parameter of the 10 items ranged from 1.82 to 3.65, and the difficulty parameter ranged from -3.51 to 1.66, with a monotonically increasing trend. The maximum test information of the scale among medical postgraduates was 19.16. Conclusion:The GSES has good reliability, validity and measurement precision, showing a good applicability in the survey of medical postgraduates. However, the difficulty of specific items is relatively low, and the scale may be further optimized and improved.

Lung cancer is the most common cancer and the leading cause of cancer-related death in China. Early screening of lung cancer proves to be effective in improving its prognosis. The National Comprehensive Cancer Network (NCCN) has updated and released version 2, 2022 NCCN clinical practice guidelines for lung cancer screening in July, 2022. Based on high-quality clinical evidence and the latest research progress, the guidelines have developed and updated criteria for lung cancer screening which have been widely recognized by clinicians around the world. Compared with Chinese lung cancer screening guidelines, this article will interpret the updated content of the brand new 2022 NCCN screening guidelines, providing some reference for the current lung cancer screening practice in our country.

Objective:To compare the prediction efficiency of traditional linear regression model and four machine learning models on the learning behavior of clinical medical postgraduates, and to explore the pros and cons and applicability of different prediction models.Methods:A total of 6,922 clinical medical postgraduates were surveyed, their comprehensive learning behavior scores were obtained through the learning behavior scale. In the training set, Lasso linear regression and artificial neural network, decision tree, Bootstrap random forest, and lifting tree were used to build prediction models respectively. The above models were used to predict the validation set data and compare the prediction efficiency.Results:The comprehensive learning behavior score of clinical medical postgraduates was (3.31±0.54) points, and the overall compliance rate was 74.02%. In the linear regression model, the influence of age, school level, degree type, learning interest, pressure and satisfaction on learning behavior were statistically significant. In the prediction of validation set, the sensitivity, specificity, and accuracy of the linear regression model were 0.484, 0.914, and 0.801, respectively. The indexes of the four machine learning models were higher than those of the traditional linear regression model, and the Bootstrap random forest had the highest elevation.Conclusion:The linear regression model has a good prediction effect on learning behavior, and machine learning is superior to linear regression model in terms of accuracy of prediction. However, traditional linear regression models are superior to machine learning models in computational efficiency and interpretability.