Objective To construct and validate an interpretable machine learning model integrating contrast-enhanced venous phase CT radiomics and clinical features for preoperative prediction of central lymph node metastasis(CLNM)of papillary thyroid carcinoma(PTC).Methods A case-control study was conducted on 243 histologically confirmed PTC patients.Among them,196 patients from the First Affiliated Hospital of Army Medical University were randomly allocated into a training set(n=137)and an internal validation set(n=59)at a 7:3 ratio,while the left 47 patients from No.958 Hospital of PLA Army were assigned into an external validation set.All participants completed standardized preoperative contrast-enhanced neck CT scanning.Quantitative radiomic features were systematically extracted from venous phase CT images through an open-source big data AI platform.Six machine learning classifiers,eXtreme Gradient Boosting(XGBoost),Support Vector Machine(SVM),Random Forest(RF),Logistic Regression(LR),k-Nearest Neighbors(KNN),and Decision Tree(DT)were implemented to construct clinical-radiomics integration models.The predictive performance was quantitatively assessed through receiver operating characteristic(ROC)curve analysis,with area under the curve(AUC)values calculated for training,internal validation,and external validation sets.Model interpretability was achieved using Shapley additive explanations(SHAP)framework,with particular focus on elucidating feature contributions in the best-performing model.Results The XGBoost model had an AUC value of 0.936(95%CI:0.895～0.976),0.832(95%CI:0.724～0.941),and 0.772(95%CI:0.632～0.912)in training,internal and external validation sets,respectively.SHAP analysis revealed age as the most influential clinical predictor,with younger patients showing higher CLNM risk(OR=0.968,P=0.042).Conclusion Our machine learning-based clinic-radiomic prediction model demonstrates satisfactory performance in predicting CLNM of PTC,providing valuable references for clinical decision-making.

Background The mental health status of prison officers is crucial to the efficiency, security, and stability of a prison, and it is essential to pay attention to the factors that influence their mental health. Objective To understand the mental health status of prison officers, and analyze how nature exposure affects their mental health problems and a potential mediating role of mental fatigue. Methods A cross-sectional survey was carried out from May to June 2022 among 1392 prison officers from eight prisons in a province, and a total of 1284 valid questionnaires were recovered. The Nature Exposure Scale, Mental Fatigue Scale, and Depression-Anxiety-Stress Scale were used to assess nature exposure, mental fatigue, and mental health indicators among prison officers, and to explore the effect of nature exposure on mental health problems and a potential mediating role of mental fatigue. Results The recruited prison officers showed high levels of depression, anxiety, and stress. The prevalence rates of depression, anxiety, and stress were 59.11% (759/1284), 60.67% (779/1284),and 43.93% (564/1284), respectively. The results of correlation analysis revealed that nature exposure was negatively related with mental fatigue and mental health indicators (depression, anxiety, and stress) (r_s=−0.242, −0.308, −0.235, −0.254, P<0.01), while mental fatigue was positively correlated with mental health indicators (depression, anxiety, and stress) (r_s=0.546, 0.533, 0.536, P<0.01). The PROCESS macro results showed that the level of nature exposure among prison officers negatively associated with depression, anxiety, and stress (β=−0.180, −0.104, −0.123), and mental fatigue played a mediating role, with indirect effects of −0.200, −0.192, and −0.199, respectively. Conclusion The levels of depression, anxiety, and stress of prison officers are higher than those of other occupations. Nature exposure negatively associates with depression, anxiety, and stress, that is, it may directly alleviate the mental health problems of prison officers; and it may also alleviate mental health problems by relieving mental fatigue.

Remote ischemic conditioning（RIC）is based on the remote application of brief ischemia and reperfusion to tissue or organ circulation，in order to protect the target tissue or organ from sustained ischemic injury.There have been extensive studies on RIC in adult diseases，but there are few studies in the field of pediatrics.In pediatrics，there are numerous diseases related to hypoxic-ischemic mechanisms.The application of RIC in children necessitates a more rigorous indications and more standardized operational procedures.This article reviews the research progress on RIC in neonatal necrotizing enterocolitis，neonatal hypoxic ischemic encephalopathy，postoperative complications of congenital heart disease，and testicular torsion，aiming to facilitate application of RIC in pediatric hypoxic-ischemic diseases.

OBJECTIVE To establish the HPLC fingerprint of Jianpi huayu decoction， and to determine the contents of 8 components. METHODS Thermo Hypersil Gold C18 column was used with mobile phase consisted of methanol-0.05% phosphoric acid aqueous solution （gradient elution） at the flow rate of 1.0 mL/min. The column temperature was 30 ℃， the injection volume was 5 μL. The detection wavelength of matrine was 211 nm， and the other components’ detection wavelength was 283 nm. The similarity evaluation of HPLC fingerprints for 10 batches of Jianpi huayu decoction was performed by using the Similarity Evaluation System of Chromatographic Fingerprint of Traditional Chinese Medicine （2012 edition）. The contents of chlorogenic acid， vanillic acid， p-coumaric acid， ferulic acid， hesperidin， quercetin， bergapten and matrine in the samples were determined by HPLC. RESULTS HPLC fingerprint of Jianpi huayu decoction was established. A total of 27 common peaks were identified， and 8 components were identified. The similarity between 10 batches of samples and the control map ranged from 0.942-0.999. RSDs of precision， repeatability and stability tests were less than 3% （n＝6）. The average recoveries of chlorogenic acid， vanillic acid， p-coumaric acid， ferulic acid， hesperidin， quercetin， bergapten and matrine were 99.48%， 101.32%， 101.18%， 100.79%， 101.12%， 99.19%， 99.81% and 102.46%， respectively； RSDs were 1.34%， 0.93%， 1.90%， 1.84%， 0.54%， 1.53%， 1.33% and 1.01%， respectively （n＝6）. The contents were 0.021-0.061， 0.025-0.034， 0.116-0.295， 0.006- 0.062， 0.014-0.053， 0.017-0.026， 0.014-0.027 and 14.05-24.11 mg/g， respectively. CONCLUSIONS The established fingerprint and content determination method can provide a reference for the quality control and subsequent preparation development for Jianpi huayu decoction.

Objective:To investigate the effect of thoracic X-ray irradiation on the spermatogenesis of adult male mice.Methods:A total of 24 healthy adult male C57BL/6 mice (6-8 weeks old) were randomly divided into radiation group (Radiation) and sham-radiation group (Sham), 12 mice in each group. The area of thoracic irradiation was 1.5 cm× 2 cm, and the dose rate was 3.04 Gy/min, 8 Gy/d for 3 consecutive days, 24 Gy in total. At 7 d and 21 d after thoracic irradiation, the bilateral testes and epididymal tails were stripped and the testicular index was calculated. The morphology of testis was examined by haematoxylin-eosin (HE) staining, then the diameter of seminiferous tubules and the thickness of seminiferous epithelium were measured. The sperms were collected from the bilateral epididymal tails for sperm counting. The level of apoptosis in testis and levels of apoptosis-related proteins were detected by TUNEL and Western blot, respectively.Results:Compared with Sham group, the morphology of testis and epididymis was seriously damaged, the diameter of seminiferous tubules significantly decreased at 21 d after irradiation ( t = 8.93, P < 0.05), and the seminiferous epithelium significantly decreased at 7 d and 21 d after irradiation ( t = 4.24, 12.77, P < 0.05). In addition, the number of sperms significantly decreased ( t = 4.30, 2.98, P < 0.05). The number of TUNEL positive cells in the seminiferous epithelium significantly increased at 7 d and 21 d after irradiation ( t = -2.73, -3.74, P < 0.05). Meanwhile, the level of cleaved Caspase-3 protein significantly increased at 7 d and 21 d after irradiation ( t = -2.96, -2.46, P < 0.05). The concentrations of SCF and GDNF did not change at 7 d after irradiation, but were significantly increased at 21 d after irradiation ( t = -10.46, -5.42, P < 0.05). Conclusions:The thoracic X-ray irradiation could lead to spermatogenesis disorder in male adult mice, and the induction of spermatogenic cell apoptosis and the secretory dysfunction of sertoli cells may be involved.

Gap junctions mediate direct communication between cells; however, toxicological cascade triggered by nonessential metals can abrogate cellular signaling mediated by gap junctions. Although cadmium (Cd) is known to induce apoptosis in organs and tissues, the mechanisms that underlie gap junction activity in Cd-induced apoptosis in BRL 3A rat liver cells has yet to be established. In this study, we showed that Cd treatment decreased the cell index (a measure of cellular electrical impedance) in BRL 3A cells. Mechanistically, we found that Cd exposure decreased expression of connexin 43 (Cx43), increased expression of p-Cx43 and elevated intracellular free Ca2+ concentration, corresponding to a decrease in gap junctional intercellular communication. Gap junction blockage pretreatment with 18β-glycyrrhizic acid (GA) promoted Cd-induced apoptosis, involving changes in expression of Bax, Bcl-2, caspase-3 and the mitochondrial transmembrane electrical potential (Δψm). Additionally, GA was found to enhance ERK and p38 activation during Cd-induced activation of mitogen-activated protein kinases, but had no significant effect on JNK activation. Our results indicated the apoptosis-related proteins and the ERK and p38 signaling pathways may participate in gap junction blockage promoting Cd-induced apoptosis in BRL 3A cells.
Animals ; Apoptosis/*drug effects ; Cadmium/*toxicity ; Calcium/metabolism ; Cell Communication/drug effects ; Connexin 43/genetics ; Enzyme Activation/drug effects ; Gap Junctions/*drug effects ; Gene Expression Regulation/drug effects ; Hepatocytes/cytology/*drug effects ; Rats ; Signal Transduction/drug effects

Proceeding from the requirements of teaching target for postgraduate students,the course of progress in pathophysiology was constructed and administrated.The course objective was defined which combined teaching knowledge with fostering students' ability together,especially the ability to think new ideas and to do scientific research.Aiming at this teaching target,the teaching contents which combined with the direction of scientific research of the department was growing together with scientific development,especially in new knowledge and new technique.Multiple teaching means and several mode of examine were adopted during the process of teaching practice.

ial of cells. It may serve as an index for monitoring and prognostic diagnosis of breast cancer.

Classroom teaching is the focus of teaching of school and main approach to medicine course,and the quality of classroom teaching is directly related to the development of students.Thus improving classroom teaching is very important to increase integral teaching of school.This paper discusses how to increase the thinking ability of students in classroom teaching.

BACKGROUNDMitochondrial DNA (mtDNA) is the only hereditary substance besides nucleus, which is composed of a code region and a non-code D-loop region. The aim of this study is to investigate the hypervariable region II (HVRII) mutation of mtDNA in peripheral blood leucocyte, pericancerous tissues and cancer tissues of lung squamous cell carcinoma patients, and to explore its significance.

METHODSWhite blood cells, pericancerous tissues and cancer tissues were obtained from 15 cases of lung squamous cell carcinoma patients and mtDNA were extracted by one step method. HVRII fragments were amplified by PCR. Mutations were determined by DNA sequencing and the mutations of HVRII were analysed.

RESULTSIn 15 lung squamous cell carcinoma patients, 14 patients showed mutation in HVRII(93.33%), 88 mutations were found totally. Eighty-seven mutations located in H-strand origin region, especially in the conserved sequence blocks and the mtTF1, 2 binding site (TFX and TFY).

CONCLUSIONSThe results suggest that the mutation frequency of HVRII in cancer tissues of lung squamous cell carcinoma patients is very high and it might play an important role in carcinogenesis of the lung.