Nitrogen oxides(NOx=NO+NO2)are important precursors of ozone(O3),and NOx and its oxides together constitute reactive nitrogen oxides(NOy)in the atmosphere.A comprehensive understanding of the total NOy level in the atmosphere is of great significance for a deeper understanding of the atmospheric nitrogen cycle and oxidation,as well as for formulating strategies for air pollution prevention and control.In this work,a thermal decomposition-broadband cavity enhanced absorption spectroscopy(TD-BBCEAS)technique for online measurement of total NOy in the atmosphere was developed.With this method,the NOy was efficiently converted into NO2,and the total NOy concentration in the atmosphere was indirectly obtained by measuring NO2.Focusing on the key factors affecting the measurement of total NOy,the influence of NO titration efficiency and other NOy component TD efficiency on measurement accuracy was emphasized.By changing the oxygen(O2)flow rate through the mercury lamp to alter the O3 concentration for titrating NO,the conversion efficiency of NO was evaluated.At O2 flow rate of 6 mL/min,the conversion efficiency of NO was greater than 99%.TD efficiency testing and analysis on NO2,peroxyacetyl nitrate(PAN),nitric acid(HNO3),and nitrous acid(HONO),which account for a large proportion of atmospheric NOy components,was carried out using 680℃as the optimal TD temperature for efficient conversion of NOy.With NO and HONO sample gases as typical verification gases,the conversion efficiency of NOy and the accuracy of NOy measurement by TD-BBCEAS system were verified by switching the on and off modes of mercury lamp and TD device.At integration time of 60 s,the detection limit of the system for NOy was 2.83×1010 molecules/cm3(60 s,2σ).A comparative measurement of actual atmospheric NOy was conducted between the TD-BBCEAS system and the NOy analyzer.The observation results showed a correlation coefficient(R2)of 0.98 and a slope of 0.93,further verifying the feasibility and accuracy of applying the TD-BBCEAS system to measurement of total NOy.

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:In order to clarify the ABO phenotype and genotype,and explore the molecular biological mechanism,serological detection,genotyping and gene sequencing were performed on an upper gastrointestinal hemorrhage patient with inconsistent forward and reverse ABO blood typing.Methods:ABO forward and reverse blood typing,H antigen identification,capillary centrifugation test and salivary substance detection were performed by classical serological method,moreover,polymerase chain reaction-sequence specific primer(PCR-SSP)was used for ABO genotyping,ABO gene 1-7 exons were sequenced by Sanger analysis in order to identify mutation.Results:Mixed field agglutination with anti-A,anti-AB and no agglutination with anti-A1 were appeared in the forward typing tests,agglutination with B cells but no agglutination with A1 cells and O cells were appeared in the reverse typing tests.3+agglutination strength was showed with anti-H.In capillary centrifugation experiment,erythrocyte after isolation in proximal part and distal end had same strength of agglutination with anti-A.Substances A and H were detected in saliva.The patient was assigned an A3 phenotype according to serological characteristics.Sequencing results of ABO gene 1-7 exons showed c.261delG,c.467C＞T,c.865A＞G,in which,865A＞G was the first discovered mutation,and this new mutation had been submitted to GenBank with accession number PP187306.Conclusion:A novel site mutation c.865A＞G is reported in this study,and this new mutation can result in a replacement of Met with Val at residue 289(p.Met289Val)and lead to an A3 phenotype.

Objective To carry out a dynamic simulation analysis on the surgical process of the surgical robot for pedicle screw placement so as to enhance the safety of the procedure.Methods Firstly,the process of pedicle screw placement were analyzed to determine the three typical force conditions during pedicle screw track drilling including no-load condition,bone layer switching condition and spine dynamic displacement condition.Secondly,a virtual protype model of the surgical robot for pedicle screw placement was constructed with the automated dynamic analysis of mechanical systems(ADAMS).Finally,the dynamic characteristics of the surgical robot were simulated and analyzed with considerations on the three typical force conditions.Results The driving torque of the robot joints was sensitive to the load applied to the end of the opener mechanism under a wide range of operating conditions.Conclusion The surgical robot meets the requirements for pedicle screw placment,and a new idea is provided for enhancing the accuracy of pedicle screw placement.[Chinese Medical Equipment Journal,2025,46(8):32-37]

A mounting body of research suggests that circRNAs significantly contribute to the develop-ment of myocardial fibrosis.The microarray results of human circular RNA expression profile indicated that circHERC4_041 expression increased in the myocardium of patients with heart failure,RT-qPCR a-nalysis confirmed that the myocardial expression level of circHERC4_041 in individuals with heart failure were considerably elevated compared to that in healthy organ donors.Fluorescence in situ hybridization(FISH)confirmed that circHERC4_041 was abundant in the cytoplasm of human cardiomyocyte AC16.Overexpression of circHERC4_041 in mouse myocardial fibroblasts(mCFs)mediated by adenovirus in-hibited the expression of fibrosis-related proteins in mCFs.Experiments involving cell proliferation,wound healing,and Transwell assays demonstrated that overexpression of circHERC4_041 suppressed the growth and mobility of mCFs(P＜0.001).Sequence analysis results suggested that circHERC4_041 con-tains potential ribosome entry sequence(IRES)and open reading frame(ORF).Western blot confirmed that circHERC4_041 could translate the 516 amino acid HERC4-516aa protein,which was mainly located in the cytoplasm of the cell.Cell functional experiments confirmed that circHERC4_041 inhibited the fi-brotic phenotype of mCFs by specifically translating HERC4-516aa(P＜0.05).The specific interaction between HERC4-516aa and transglutaminase 2(TGM2)was confirmed by IP-MS screening and Co-IP i-dentification.Further results found that the degradation of TGM2 was promoted through proteasome path-way.The overexpression of TGM2 in mCFs facilitated by adenoviral vectors could counteract the suppres-sive effects of HERC4-516aa on the fibrotic phenotype of mCFs.Therefore,this study confirmed that the HERC4-516aa protein translated by circHERC4_041 can specifically bind to TGM2 to inhibit the fibrotic phenotype of myocardial fibroblasts.

Aim To explore the effect of FTO on adria-mycin resistance in triple-negative breast cancer through the Wnt/β-catenin signaling pathway and to reveal the underlying mechanism.Methods The MDA-MB-231/ADR drug-resistant cell line was constructed using a method of gradually increasing adriamycin concentra-tion with intermittent induction.The half-inhibitory concentration(IC50)of adriamycin for MDA-MB-231 and MDA-MB-231/ADR cells and the expression of FTO were compared.After knocking down FTO in MDA-MB-231/ADR cells,CCK-8,qRT-PCR,colony formation assay,transwell,flow cytometry,and Western blot were used to assess the changes in the IC50 of adri-amycin,cell proliferation,migration,invasion,apopto-sis,and the expression of related proteins.Results FTO was highly expressed in MDA-MB-231/ADR cells.After FTO knockdown,the IC50 value of adriamy-cin in MDA-MB-231/ADR cells decreased,and the a-bilities of proliferation,migration and invasion were weakened.In the FTO knockdown group,the expres-sion levels of Bax,cleaved-caspase3,GSK-3 β proteins and the apoptosis rate significantly increased,while the expression levels of Bcl-2,Wnt5a,β-catenin,c-myc,cyclin D1,and P-gp proteins decreased.Conclusion FTO may inhibit the apoptosis of MDA-MB-231/ADR cells through the Wnt/β-catenin signaling pathway,al-ter P-gp expression,and thereby enhance the resistance of MDA-MB-231/ADR cells to adriamycin.

A mounting body of research suggests that circRNAs significantly contribute to the develop-ment of myocardial fibrosis.The microarray results of human circular RNA expression profile indicated that circHERC4_041 expression increased in the myocardium of patients with heart failure,RT-qPCR a-nalysis confirmed that the myocardial expression level of circHERC4_041 in individuals with heart failure were considerably elevated compared to that in healthy organ donors.Fluorescence in situ hybridization(FISH)confirmed that circHERC4_041 was abundant in the cytoplasm of human cardiomyocyte AC16.Overexpression of circHERC4_041 in mouse myocardial fibroblasts(mCFs)mediated by adenovirus in-hibited the expression of fibrosis-related proteins in mCFs.Experiments involving cell proliferation,wound healing,and Transwell assays demonstrated that overexpression of circHERC4_041 suppressed the growth and mobility of mCFs(P＜0.001).Sequence analysis results suggested that circHERC4_041 con-tains potential ribosome entry sequence(IRES)and open reading frame(ORF).Western blot confirmed that circHERC4_041 could translate the 516 amino acid HERC4-516aa protein,which was mainly located in the cytoplasm of the cell.Cell functional experiments confirmed that circHERC4_041 inhibited the fi-brotic phenotype of mCFs by specifically translating HERC4-516aa(P＜0.05).The specific interaction between HERC4-516aa and transglutaminase 2(TGM2)was confirmed by IP-MS screening and Co-IP i-dentification.Further results found that the degradation of TGM2 was promoted through proteasome path-way.The overexpression of TGM2 in mCFs facilitated by adenoviral vectors could counteract the suppres-sive effects of HERC4-516aa on the fibrotic phenotype of mCFs.Therefore,this study confirmed that the HERC4-516aa protein translated by circHERC4_041 can specifically bind to TGM2 to inhibit the fibrotic phenotype of myocardial fibroblasts.

Objective:To identify core genes with co-expression trends in the suprachiasmatic nucleus (SCN) and lateral habenula (LHb) through miRNA sequencing, and to explore the molecular mechanisms underlying the onset and progress of sleep disturbances in depression.Methods:A rat model of depression with sleep disturbances was established. Behavioral assessments were conducted using the pentobarbital-induced sleep test, sucrose water consumption test, and open field test. Differentially expressed genes (DEGs) in the SCN and LHb of model rats were analyzed using biological replicates with the limma package and DESeq2 software. Gene ontology (GO), KEGG, Reactome pathway-gene set enrichment analysis (GSEA) were performed on the DEGs.Co-expression networks and protein-protein interaction (PPI) networks were constructed using R and Cytoscape software for further screening of genes with potential regulatory roles.Results:After modeling, the sleep latency in the model group ((679.88±350.05) s) was longer than that in the normal group ((316.25±87.35) s) ( t=-2.851, P=0.022), while the sleep duration in the model group ((33.13±8.41) min) was shorter than that in the normal group ((69.72±25.11) min) ( t=3.907, P=0.004). Additionally, the model group exhibited lower sucrose water consumption, horizontal movement counts, and vertical movement counts compared to the normal group (all P<0.05). Differential expression gene analysis showed, in the SCN, 379 genes were upregulated and 132 genes were downregulated, with the top five most significantly differentially expressed genes being Sec61g, Cox6b1, Ephx2, Thrsp, and Pak2. In the LHb, 1 657 genes were upregulated and 1 737 were downregulated, with the top five most significantly differentially expressed genes being Mrpl32, Mrpl20, Mrpl27, Celsr2, and Uba52. Biological pathways enriched in the SCN were mainly associated with the positive regulation of responses to external and biological stimuli. In contrast, pathways enriched in the LHb were related to neurotransmitter level regulation, developmental growth, neurotransmitter transport, and processes such as learning and memory. Co-expression network analysis identified 864 interactions involving 100 nodes in the SCN and 524 interactions involving 99 nodes in the LHb. Conclusion:The biological functions and signaling pathways of the suprachiasmatic nucleus and lateral habenula are different in the occurrence and development of depression with sleep disturbance, and the significantly differentially expressed genes may play an important role.

Aim To explore the effect of the classical famous prescription Dahuang Zhechong pill(DHZCP)on relieving liver cirrhosis by regulating the stress fiber remodeling mediated by mechanistic signaling pathway and to explore the underlying mechanism.Methods Mice were randomly divided into the control group,model group,DHZCP low-dose group,DHZCP high-dose group,and Colchicine-positive control group.The liver cirrhosis mouse model was constructed by intrap-eritoneal injection of olive oil-solubilized CCl4.HE staining and serologic markers were used to reflect liver injury.Masson staining was used to evaluate collagen deposition in liver tissue.ELISA was applied to detect vasoactive molecules and cancer indicators.Atomic force microscopy was employed to detect liver tissue stiffness.Color Doppler diagnostic instrument was used to assess portal blood flow velocity.Western blot was utilized to detect ROCK2 expression and phosphoryla-tion of YAP,Cofilin,and MLC.Results The liver tis-sues in the model group had obvious inflammatory cell infiltration and collagen deposition,accompanied by significant elevation of serum transaminases and fibrosis indexes.Similarly,vasoactive molecules and cancer in-dicators were elevated,and the mechanoregulatory pro-tein ROCK2 expression and phosphorylation of Cofilin and MLC were elevated,with YAP being strongly de-phosphorylated.Both low and high doses of DHZCP re-versed the pathological changes,serological indices,and inhibited the activation of the stress fiber(SF)re-modeling mechanistic signaling pathway.Conclusion DHZCP effectively ameliorates liver tissue lesions in mice with liver cirrhosis,and its mechanism may be re-lated to the inhibition of SF remodeling mechanistic signaling pathway.

The molecular mechanisms underlying the develop-ment and metastasis of prostate cancer remain elusive.This comprehensive review delves into the intricate role of cofilin,an actin-binding protein,in the pathogenesis and progression of prostate cancer.Cofilin is a significant protein in cytoskeletal dynamics,and any dysregulation may result in the morphological changes in normal cells and the invasion and metastasis of tumor cells.Research has revealed that the activity of cofilin is regula-ted by various mechanisms,including phosphorylation/dephos-phorylation and interactions with other molecules.Moreover,this review discusses promising therapeutic interventions,such as co-filin inhibitors and gene therapy,which have demonstrated effica-cy in preclinical models.The challenge of clinically preventing the transition to castration-resistant prostate cancer and tumor metastasis is widely recognized,necessitating the development of precise drug treatments and biomarker identification.As a key regulatory protein,cofilin provides a more comprehensive refer-ence for the prevention and treatment of prostate diseases.