Objective To investigate the expression characteristics and clinical diagnostic value of programmed death receptor 1(PD-1)and its corresponding ligand(PD-L1)in patients with acute exacerbation of chronic obstructive pulmonary disease(AECOPD).Methods One hundred and sixty COPD patients who visited Dongzhimen Hospital of Beijing University of Chinese Medicine from April 2024 to November 2024 were included and divided into an acute exacerbation group of 100 cases and a stable group of 60 cases according to the severity of the disease.Additionally,40 healthy volunteers during the same period were recruited as the control group.The general clinical data of the patients were collected.Chronic Obstructive Pulmonary Disease Assessment Test(CAT)and Modified Medical Research Council Dyspnea Questionnaire(mMRC)Scale were used to test the severity of the disease;respiratory function testing was performed and fasting venous blood was collected for serum PD-1 and PD-L1 testing.Pearson correlation was used to analyze the correlation between serum PD-1,PD-L1,CAT,and mMRC,and multiple logistic regression analysis to identify the influencing factors of AECOPD.Receiver operating characteristic(ROC)curve was drawn to evaluate the diagnostic value of serum PD-1 and PD-L1 level for AECOPD.Results Serum PD-1 level in the stable COPD group and AECOPD group was significantly increased compared with that in the control group,while serum PD-L1 level was significantly decreased,showing statistical significance(P<0.05);The level of PD-1 gradually increased with the grading of lung function and the deterioration of AECOPD,with statistical significance(P<0.05);Pearson correlation showed that serum PD-1 level was positively correlated with CAT scores in COPD patients,while negatively with CAT scores,showing statistical significance(P<0.05);Multiple logistic regression analysis showed that elevated levels of serum inter-leukin-6(IL-6),neutrophil to lymphocyte ratio(NLR),and PD-1 were risk factors for AECOPD,while elevated level of PD-L1 was protective factor for AECOPD(P<0.05);ROC curve showed that the levels of PD-1,PD-L1,IL-6,NLR,and the area under the ROC curve(AUC)for their combined prediction of AECOPD diagnosis were 0.884,0.867,0.868,0.802,and 0.995,respectively.Conclusion Serum PD-1 and PD-L1 in AECOPD patients have presented certain expression characteristics,with elevated PD-1 level while decreased PD-L1 level.Both have good clinical diagnostic value for AECOPD.

Objective:To conduct an occupational hygiene investigation and simulated sampling and testing on welding positions in a company in a certain province, and to perform a simulated analysis of the concentration of occupational hazard factors in workers suspected of occupational asthma.Methods:In November 2023, the investigation and analysis of workers' exposure to occupational hazard factors were carried out through occupational hygiene surveys, laboratory simulated sampling and testing, and a combination of qualitative and quantitative detection methods.Results:Toluene diisocyanate (TDI) was present in the workplace air of the employer. TDI was detected in the raw materials provided by the workers. Laboratory simulations of the production process and working conditions at the position were conducted with sampling at different distances, revealing a maximum TDI concentration of 0.49 mg/m 3 and a minimum concentration of 0.01 mg/m 3. The results showed that the closer the sampling distance was to the breathing zone, the more significantly the TDI concentration increased. The laboratory simulated sampling and testing results were highly consistent with the on-site sampling and testing results from a testing agency in Beijing. Conclusion:The occupational hazard factor TDI is present in the workers' workplace, and TDI may be the cause of the suspected occupational asthma in the workers.

Objective:To evaluate the effects and underlying mechanisms of preoperative intestinal microbiota modulation on the recovery of prolonged postoperative ileus(PPOI)in gastric cancer patients with sarcopenia Methods:Skeletal muscle mass(SMM)was assessed using bioelectrical impedance analysis(BIA),and the skeletal muscle index(SMI)was calculated.A total of 156 gastric cancer patients with sarcopenia who underwent surgery at the Department of Gastrointestinal Surgery,Liyang People's Hospital,from January 2022 to December 2024 were randomly assigned to either the control group or the experimental group.The control group received conventional prehabilitation interventions,including nutritional support,respiratory function training,and physical exercise.The experimental group received probiotic-based intestinal microbiota modulation in addition to conventional prehabilitation interventions.Postoperative recovery indicators,including time to first flatus,incidence of postoperative complications,length of hospital stay,and hospitalization costs,were compared between the two groups.Results:Among the 156 sarcopenic gastric cancer patients,121 were male,and 35 were female.Statistically significant differences were observed between the two groups in terms of time to first flatus,incidence of postoperative complications,and length of hospital stay(P<0.05).Postoperative complications occurred in 38 patients(24.3%),with 10 cases(6.4%)in the experimental group and 28 cases(17.9%)in the control group.The time to first flatus in the experimental group was significantly shorter than in the control group(48.0 hours vs 72.0 hours,P<0.001).Conclusion:Preoperative intestinal microbiota modulation significantly reduces the incidence of PPOI and postoperative complications in gastric cancer patients with low SMI,thereby promoting postoperative gastrointestinal function recovery.

″Boundarics in biomedicine″(or″Biomedical boundarics″)is an emerging frontier interdisciplinary subject that focuses on addressing key scientific issues related to the formation,identification,and evolution of biological boundaries within living organisms.In this field,the study of tumor boundaries is of particular importance.Imaging tumor boundaries not only helps to reveal the molecular mechanisms of tumor boundary evolution and interaction with the microenvironment,tumor invasion and metastasis,but is also crucial for clinical tumor diagnosis,treatment decision-making,efficacy monitoring and prognosis evaluation.Molecular probes,as functional substances that enhance imaging signals,play a crucial role in tumor boundary recognition.In this article,the basic concepts and research significance of boundarics in biomedicine and tumor boundarics in biomedicine were summarized firstly.Then a comprehensive review of the research progress in tumor boundary imaging molecular probes was provided,covering areas such as magnetic imaging,optical imaging,acoustic imaging,nuclear imaging,and multimodal imaging.The strategies to regulate the sensitivity,specificity,and safety of molecular probes through chemical structure modifications,conjugation with targeting ligands,and tumor microenvironment-responsive designs were emphasized.Finally,the research trends of molecular probes for tumor boundary imaging were analyzed,and the challenges faced in this field and the future research directions were discussed.

A method was developed for determination of dilauryl thiodipropionate(DLTDP)in fried foods by coupling solid-phase extraction(SPE)pretreatment with reverse-phase liquid chromatography-tandem mass spectrometry(RPLC-MS/MS)detection.Samples were extracted with n-hexane as the solvent,purified using a neutral alumina SPE cartridge,and finally analyzed by RPLC-MS/MS.Quantitative analysis was performed using matrix-matched calibration curves combined with an external standard method under optimal experimental conditions.The results showed that DLTDP exhibited good linearity in the range of 2.0-50.0 μg/L,with a correlation coefficient(R2)≥0.999.The limit of detection(LOD)and the limit of quantification(LOQ)of the method were 0.15 mg/kg and 0.5 mg/kg,respectively.The mean recoveries at three fortification levels(0.5,1.0,and 200 mg/kg)in different samples ranged from 84.8%to 96.8%,with the relative standard deviations(RSDs)all less than 8.0%.The developed method was highly sensitive,accurate and reliable,and easy to operate,making it well suited for the routine quantitative analysis of DLTDP in fried foods.

Objective To construct a competency evaluation model for forensic practitioners,providing a reference for their training and assessment.Methods Based on the iceberg and onion models of com-petency,and with reference to Spencer's Competency Dictionary,literature research was conducted and focus group interviews were employed to preliminarily construct core indices and measurement items for evaluating the competency of forensic practitioners.The Delphi method was applied for two rounds of expert consultation to further refine the competency evaluation index system.The analytic hierarchy process(AHP)was used to calculate the weights of the indices.Results A competency evaluation model for forensic practitioners was constructed,consisting of 7 core indices,encompassing forensic skills,identification service capabilities,and the ability to apply relevant legal knowledge and 49 mea-surement items.The weights of the core indices and measurement items were determined.Conclusion The constructed competency evaluation model for forensic practitioners is scientifically sound and inno-vative,and has unique characteristics of forensic medicine compared with other medical models.

Turning to critical illness is a common stage of various diseases and injuries before death. Patients usually have complex health conditions, while the treatment process involves a wide range of content, along with high requirements for doctor′s professionalism and multi-specialty teamwork, as well as a great demand for time-sensitive treatments. However, this is not matched with critical care professionals and the current state of medical care in China. Telemedicine, which shortens the distance of medical professionals and the gap of disease diagnosis and treatments in various regions through electronic information, can effectively solve the current problem. Therefore, there is an urgent need to develop a standardized, high-quality visualization telemedicine round system .Therefore, experts have been organized to search domestic and foreign literature on telemedicine round for critically ill patients and to form this consensus based on clinical experiences so as to further improve the level of critical care treatments in regions.

Objective:To quantitatively detect plasma ceramide (Cer) levels using high-performance liquid chromatography tandem mass spectrometry (LC-MS/MS) and analyze plasma ceramide levels in homozygous familial hypercholesterolemia (HoFH) patients.Methods:A case-control study was conducted. Plasma samples were collected from 70 healthy individuals who underwent physical examinations at the Health Check-Up Center of Suzhou Municipal Hospital between October 2023 and December 2023, as well as from 34 HoFH patients (including 11 patients with concomitant coronary artery disease) who were treated in the Cardiology Department of the same hospital during the same period. Deuterated isotopes were used as internal standards, and a Phenomenex Kinetex C18 column (2.1×100 mm, 2.6 μm) was employed for separation. An LC-MS/MS method was developed using an AB Sciex 6500+triple quadrupole mass spectrometer for the detection of ceramides, followed by method validation. Additionally, the differences in ceramide levels among healthy individuals, HoFH patients, and HoFH patients with concomitant coronary artery disease were compared. Receiver operating characteristic (ROC) curves were used to evaluate the diagnostic value of various ceramides for HoFH.Results:A method for the quantification of 9 plasma ceramides was established, showing excellent linearity ( r>0.99), precision (1.8%-11.0%), and recovery rates (89.9%-114.7%), meeting the requirements for detection. Compared to the control group, the HoFH group exhibited significantly higher levels of Cer(d18∶1/14∶0), Cer(d18∶1/16∶0), Cer (d18∶1/18∶0), Cer (d18∶1/18∶1), Cer (d18∶1/20∶0), Cer(d18∶1/22∶0), Cer(d18∶1/24∶0), and Cer(d18∶1/24∶1) ( P<0.05). ROC curve analysis revealed that Cer(d18∶1/18∶0) had the highest diagnostic value for HoFH, with an area under the curve (AUC) of 0.83, a cutoff value of 64.6 ng/ml, and sensitivity and specificity of 82.4% and 87.1%, respectively. In HoFH patients complicated with coronary artery disease, the plasma ceramide levels of Cer(d18∶1/18∶0) [(155.7±25.1) ng/ml vs (103.0±11.1) ng/ml, P=0.03] and the ratio of Cer (d18∶1/18∶0) to Cer(d18∶1/24∶0) (0.077±0.012 vs 0.048±0.006, P=0.03) were significantly higher than in HoFH patients without coronary artery disease. Conclusion:A quantitative LC-MS/MS method was developed for detecting ceramides in human plasma, which shows potential diagnostic value for patients with HoFH.

AIM To investigate the effects of Rutong Ruanjian Tablets on angiogenesis in cancer tissues of rats with preneoplastic breast cancer(PBC).METHODS 60 female SD rats were randomly divided into a blank group of 10 rats and a model group of 50 rats for the establishment of the PBC models of Liver-Qi Stagnation and Blood Stasis Pattern with 9 weeks of oral administration of 7,12-dimethylbenz[a]anthracene(DMBA)and cervical ligation.After successful modeling,the rats were randomly divided into the model group,the tamoxifen group(3.2 mg/kg),the Rutong Ruanjian Tablets group(128 mg/kg),the 3,5-difluorobenzoyl group(DAPT,5 mg/kg),and the Rutong Ruanjian Tablets(128 mg/kg via gavage)+DAPT(5 mg/kg intraperitoneal injection)group,for 1 month corresponding drug administration,with 10 rats in each group.Then the rats had their cancer progression and syndrome scores observed;their angiogenesis evaluated by assessment of microvascular density(MVD);their vascular endothelial growth factor(VEGF)expression assessed by immunohistochemistry;and their mRNA and protein expressions of proteins related to the DLL4/Notch1/Hes1 pathway measured using RT-qPCR,immunohistochemistry and Western blot.RESULTS During carcinogenesis of rats induced by DMBA,there was gradual disappearance of E-cadherin expression and consistency of HE staining result with the PBC progression confirming the success of the modeling.Compared with the blank group,the model group showed increased MVD values,mRNA expression of Notch1 and Hes1,and protein expressions of VEGF,DLL4,Notch1 and Hes1(P＜0.05,P＜0.01).Compared with the model group,the Rutong Ruanjian Tablets group exhibited reduced MVD values,mRNA expression of Notch1 and Hes1,and protein expressions of VEGF,DLL4,Notch1 and Hes1(P＜0.05,P＜0.01).The Rutong Ruanjian Tablets+DAPT group showed reduced mRNA expression of Notch1 and Hes1,and protein expressions of DLL4,Notch1 and Hes1 compared to the Rutong Ruanjian Tablets group(P＜0.05,P＜0.01).CONCLUSION Rutong Ruanjian Tablets can inhibit angiogenesis and attenuate cancer progression in PBC rats of Liver-Qi Stagnation and Blood Stasis Pattern,and the mechanism may lie in the downregulation of DLL4/Notch1/Hes1 signaling pathway related proteins.

Aim To investigate the effect of long-chain non-coding RNA(lncRNA)GS1-124K5.4 targeting regulation of PRDX6 on proliferation,migration and in-vasion of lung squamous carcinoma(LUSC)cells and the underlying mechanism.Methods The expression level of lncRNA GS1-124K5.4 in lung cancer tissues and adjacent tissues of 60 patients with LUSC were de-termined by fluorescence in situ hybridization.The ex-pression level of lncRNA GS1-124K5.4 in human nor-mal lung cells and LUSC cells were determined by qRT-PCR.Two kinds of LUSC cells(NCI-H 1703,SK-MES-1)with highest expression level of lncRNA GS1-124K5.4 were selected for subsequent experi-ments.The distribution of lncRNA GS1-124K5.4 in cells was studied by fluorescence in situ hybridization and prokaryotic separation.The effect of knockdown of lncRNA GS1-124K5.4 on proliferation of NCI-H1703 and SK-MES-1 cells was studied by CCK-8 experiment and cell clone formation experiment;the effect of knockdown of lncRNA GS1-124K5.4 on migration of NCI-H1703 and SK-MES-1 cells was studied by cell scratch experiment and Transwell cell migration experi-ment;and the effect of knockdown of lncRNA GS1-124K5.4 on invasion of NCI-H1703 and SK-MES-1 cells was studied by Transwell invasion experiment.The protein to be bound by lncRNA GS1-124K5.4 was detected by RNA pull-down combined with mass spec-trometry and immune-precipitation.The effect of knockdown of lncRNA GS1-124K5.4 targeting PRDX6 on proliferation,migration and invasion of NCI-H1703 and SK-MES-1 cells was studied.Results(1)The fluorescence intensity of lncRNA GS1-124K5.4 in lung squamous cell carcinoma increased compared with that in adjacent tissues(P＜0.05),and the expression of lncRNA GS1-124K5.4 was related with lymph node metastasis and clinical stage(P＜0.05).(2)The ex-pression level of lncRNA GS1-124K5.4 in NCI-H1703,NCI-H520 and SK-MES-1 cells significantly increased(P＜0.05).(3)The result of fluorescence in situ hybridization experiment and nucleoplasm sepa-ration experiment showed that lncRNA GS1-124K5.4 was mainly distributed in cell nucleus.(4)The prolif-eration,migration and invasion ability of NCI-H1703 and SK-MES-1 cells with knockdown of lncRNA GS1-124K5.4 significantly decreased(P＜0.05).(5)PRDX6 protein to be bound to LncRNA GS1-124K5.4 was determined by RNA pull-down combined with mass spectrometry and immunoprecipitation.(6)The prolif-eration,migration and invasion ability of NCI-H1703 and SK-MES-1 cells with overexpression of lncRNA GS1-124K5.4 significantly increased(P＜0.05);the proliferation,migration and invasion ability of NCI-H1703 and SK-MES-1 cells with knockdown of PRDX6 significantly decreased(P＜0.05);the proliferation,migration and invasion ability of NCI-H1703 and SK-MES-1 cells with overexpression of lncRNAGS1-124K5.4 and knockdown of PRDX6 showed no signifi-cant change(P＞0.05).Conclusions LncRNA GS1-124K5.4 is highly expressed in lung squamous cell carcinoma,and it may promote the proliferation,migration and invasion of lung squamous carcinoma cells by targeting the expression of PRDX6 protein.