The blue fluorescent carbon dots(TMCDs)and cyan fluorescent carbon dots(TMCDs-H2O)were synthesized fromm-phenylenediamine and tricarballylic acid through air-assisted melting polymerization and one-step hydrothermal method,respectively.Air purging could effectively inhibit the side reactions and reduce the derivative structures in the carbon dots product.The structure and morphology of these two materials were systematically characterized using liquid nuclear magnetic resonance spectroscopy(NMR),mass spectrometry(MS),and transmission electron microscopy.Compared to TMCDs-H2O((3.12±0.63)nm),TMCDs showed a smaller average particle size(approximately(1.85±0.02)nm).The NMR and MS analysis revealed that although the main structure of both types of carbon dots was similar,TMCDs exhibited a simpler structure with higher degree of polymerization.These results suggested that supramolecular interactions might introduce numerous small molecule derivatives into TMCDs-H2O particles,resulting in lower polymerization degree,multiple substructures,and larger particle size characteristics for this material.When employed as chemical sensors for metal ion detection,in the linear range of 1×10-5-5×10-4 mol/L,the detection limits of Fe3+by TMCDs and TMCDs-H2O were 3.3×10-6 mol/L and 3.8×10-6 mol/L,respectively.The experimental results demonstrated that the recoveries of CDs and inductively coupled plasma optical emission spectrometer(ICP-OES)were similarity,whereas TMCDs displayed a considerable relative standard deviation.This study demonstrated that endogenously derived structures in CDs could enhance the performance of metal ion sensing.

Objective To explore the mechanism of myocardial toxicity caused by N-methyl-3,4-methyle-nedioxyamphetamine(MDMA),the changes of intracellular calcium oscillation mode and calcium han-dling proteins during acute exposure to different concentrations of MDMA were detected,and the in-volvement of nuclear factor κB(NF-κB)and its effect on calcium handling proteins were investigated.Methods Primary rat cardiomyocytes were cultured to establish MDMA acute exposure model,and a control group was set up.The MDMA poisoning model was divided into three concentration groups of 10,100 and 1 000 μmol/L.After 1 h of exposure,the morphological changes of cardiomyocytes were ob-served,the cytotoxicity and changes in calcium signals were measured,and the changes in calcium handling proteins RyR2,SERCA2a,PLN,NCX1 and Cav1.2 were detected.The changes of NF-κB activity and the expression of nucleoprotein p-p65(Ser311)and PKCζ after MDMA exposure,and the intervention of NF-κB inhibitors pyrrolidine dithiocarbamate ammonium(PDTC)and protein kinase C(PKC)inhibitor chelerythrine(CHE)were detected by electrophoretic mobility shift assay(EMSA)and Western blotting.The effects of PDTC intervention on calcium signals,and the expressions of RyR2,SERCA2a,PLN,NCX1 and Cav1.2 after acute MDMA exposure were also observed.Results No obvious changes were observed in the morphology of cardiomyocytes after acute exposure to MDMA,whereas the oscillation waveform of intracytoplasmic calcium ion showed irregular changes with increased oscillation amplitude,intense fluctuations,irregular frequency,and increased fluctuation range of relative optical density values.The expression of RyR2,SERCA2a and NCX1 increased,while the expression of Cav1.2 and PLN de-creased.Acute MDMA exposure could increase NF-κB activity,while PDTC and CHE intervention could inhibit NF-κB activity.In MDMA exposed group,the expression of PKCζ and nucleoprotein p-p65(Ser311)both increased and could be inhibited by CHE.After the intervention of PDTC to block NF-κB,the amplitude of calcium oscillation was lower than that of the MDMA exposed group,and the expres-sion of RyR2,SERCA2a and NCX1 decreased.There was no significant change in PLN,while the ex-pression of Cav1.2 increased.Conclusion MDMA can lead to an increase of calcium ion concentration in cardiomyocytes.Calcium ions are involved in myocardial toxicity of MDMA.The mechanism is re-lated to changes in calcium handling proteins,mainly associated with the increased expression of RyR2.MDMA can up-regulate the intracellular activity of NF-κB through the PKCζ-NF-κB pathway and affect calcium handling proteins,which aggravate intracellular calcium overload during acute MDMA exposure.

Aim To explore the influence of demethy-lase fat mass and obesity-related genes(FTO)on the abnormal contractile function of diabetic coronary smooth muscle.Methods Smooth muscle specific FTO knockout mice(FTOSMKO)were prepared by Cre-loxP recombinant technology.They were divided into four groups:control(WT)group,diabetes model group(DM),FTO knockout group(FTOSMKO),and FTOSMKO diabetic group(FTOSMKO-DM),with 15 mice in each group.Diabetic mice were prepared by intraperitoneal injection of streptozotocin(STZ);the remaining mice were injected with an equal amount of citric acid-sodi-um citrate buffer.The effects of 5-HTon the contractile response of coronary artery smooth muscle in the four groups of mice were observed by the technique of small-vessel ring tensiometry.Western blot and Dot blot were used to detect the changes of FTO protein and N6-methyladenine(m6A)methylation modification levels in mouse vascular tissues.Results Compared with the WT group,the DM group had significantly higher blood glucose(P＜0.01)and lower body weight(P＜0.05);the level of FTO protein in aorta of DM group increased(P＜0.01),and the level of m6A methylation modification decreased(P＜0.01).The 5-HT-induced contractile response significantly de-creased in the DM group compared with the WT group(P＜0.01),whereas the contractile response signifi-cantly increased in the FTOSMKO-DM group compared with the DM group(P＜0.01);the non-L-type calci-um channel-mediated vascular smooth muscle contrac-tile response was enhanced in the FTOSMKO-DM group,among which,the contractions induced by 1,4,5-triphosphate inositol receptor(IP3R)and caffeine-ac-tivated ranine receptor(RyR)mediated by sarcoplas-mic reticulum calcium release both significantly in-creased(P＜0.05).Conclusions Specific knock-down of smooth muscle FTO improves coronary artery responsiveness to the vasoconstrictor 5-HT in diabetic mice,which may be related to abnormalities in the FTO-mediated 5-HT receptor signaling pathway.

Objective To analyze the imaging features of cerebral small vessel disease in patients with type 2 diabetes mellitus by multimodal MRI.Methods The clinical data of 160 patients with cerebral small vessel disease admitted to our hospital from January to December 2020 were retrospectively analyzed.According to whether they were complicated with type 2 diabetes mellitus,they were divided into the diabetic group and the non-diabetic group,with 80 cases in each group.Both groups underwent multimodal MRI scans.And the severity of lacunar infarction,the severity of subcortical and periventricular white matter lesions,white matter integral and cerebral microbleeds of patients in the two groups were compared.Results The severity of lacunar infarction(χ2=34.076,P=0.001),subcortical white matter lesions(χ2=25.000,P=0.001),periventricular white matter lesions(χ2=22.895,P=0.001)and white matter integral(t=12.370,P=0.001)of patients in the diabetic group were significantly higher than those in the non-diabetic group.No cerebral microbleeds were detected in either group of patients.Conclusion Patients with cerebral small vessel disease and type 2 diabetes mellitus show characteristic multimodal MRI changes.The increase in the number of lacunar infarction lesions and the aggravation of white matter lesions can be used as the characteristic imaging basis for the diagnosis of type 2 diabetes mellitus related cerebral small vessel disease.

Objective:To establish a mouse model of liver cancer resistant to PD-1 monoclonal antibody and analyze the changes in its metabolomics to explore the potential mechanism of drug resistance.Methods:BALB/c mice were randomly divided into control and treatment groups after being loaded with tumor,and a normal group was additionally set up.The normal and control groups were injected with saline,and the treatment group was injected with PD-1 monoclonal antibody,after which the mice in the treatment group were screened for drug resistant and response groups.Observed the drug-resistant situation,body mass,tumor growth and survival rate of mice in each group,calculate the spleen index.The pathological features of tumor tissues were observed by HE staining method.Serum metabolites were detected by non-targeted metabolomics.Finally,a bivariate Pearson correlation analysis was conducted between the differential serum metabolites and tumor size.Results:The tumor-bearing mouse model with PD-1 monoclonal antibody resistance was successfully established,and the drug resistance rate of the mice was 50％.Compared with the normal and response groups,mice in the resistant group showed an increase in body weight,a significant increase in tumor volume,a decrease in survival rate,and a significant increase in splenic index.There was less lymphocyte infiltration in the tumor tissue.Metabolomics analysis showed that the serum levels of glutamic acid and aspartic acid increased and malic acid decreased in the resistant mice compared with the response group,and these changes were closely related to the arginine biosynthesis pathway.Conclusions:The tumor-bearing mouse model with PD-1 monoclonal antibody resistance was successfully established.The changes in its peripheral serum metabolomics mainly involve arginine metabolism and the related changes of aspartate,malate and glutamate.

Aim To explore the mechanism of ligustil-ide(LIG)improving demyelination by inhibiting in-flammatory response in mice with distal middle cerebral artery occlusion(dMCAO)through AIM2/caspase-1 signal pathway.Methods Thirty C57BL/6N male mice were randomly divided into three groups:sham operation group(Sham group,n=10),model group(dMCAO group,n=10)and treatment group(LIG group,n=10).The dMCAO mouse model was estab-lished by electrocoagulation in dMCAO group and LIG group.The mice were scored by Longa after waking up,and the changes of cerebral blood flow were moni-tored by laser speckle blood flow imaging system after dMCAO.One hour after modeling,LIG(30 mg·kg-1·d-1)was injected intraperitoneally in LIG group,and the same amount of normal saline was injected in sham group and dMCAO group for one week until the end of the experiment.The mice in each group were stained with TTC,and the brain injury was observed pathologically.Fatigue turning bar test and open field test were used to evaluate the motor function and anxie-ty degree of mice,and then the brain tissues of mice were taken for black gold staining to compare the chan-ges of myelin sheath in each group.Immunofluores-cence staining was used to detect the average fluores-cence intensity of MBP,IBA1 and GFAP in CC,CPU and CX regions of mouse brains.ELISAwas used to de-tect the contents of TNF-α,IL-6,IL-1 β,IL-17A and BDNF in brain tissue proteins of mice.Western blot-ting was used to detect the protein expressions of AIM2,caspase-1 and ASC-in each group.Results Compared with the dMCAO group,the infarct area was reduced,the behavior was significantly improved and the demyelination was reduced in the LIG group.The expression of MBP protein in CC,CPU and CX regions increased(P＜0.05),the expression of IBA1 in CX decreased(P＜0.01),and the expression of GFAP in-creased in CC,CPU and CX regions(P＜0.01).The results of ELISA showed that the levels ofTNF-α(P＜0.01),IL-6(P＜0.01),IL-1β(P＜0.05)and IL-17A(P＜0.01)significantly decreased,while the ex-pression of BDNF increased(P＜0.05).The protein expression levels of AIM2,caspase-1 and ASC in mouse brain decreased after treatment(P＜0.01).Conclusion LIG has a protective effect on demyelina-tion in dMCAO mice,which may be related to the inhi-bition of AIM2/caspase-1 signaling pathway and in-flammation and to the promotion of BDNF secretion.

Aging is the result of the accumulation of various molecular and cellular damages over time,encompassing 12 characteristic hallmarks divided into three categories.These include primary hallmarks such as genomic instability,telomere attrition,epigenetic alterations,loss of proteostasis,and disabled macroautophagy;antagonistic hallmarks like deregulated nutrient sensing,mitochondrial dysfunction,and cellular senescence;and integrative hallmarks including stem cell exhaustion,altered intercellular com-munication,chronic inflammation and dysbiosis.Therefore,investigating cellular signaling factors within a single pathway is insufficient to comprehensively understand the complex mechanisms underlying aging.Casein kinase Ⅱ(CK2),one of the earliest identified protein kinases,is capable of phosphorylating ser-ine/threonine/tyrosine residues on hundreds of substrates.It exhibits highly constitutive expression and activity,and is extensively involved in the regulation of cellular processes such as proliferation,differenti-ation,apoptosis,stress response,metabolism,and immune function.CK2 plays a unique role in coordi-nating the cross-talk and integration of various signaling pathways,which is crucial for maintaining cell survival and homeostasis.Recent studies have revealed that CK2 exhibits perturbations in both expression levels and enzymatic activity during aging process,with notable heterogeneity observed across different animals,tissues and cellular models.Overall,the downregulation of CK2 expression not only promotes the development of primary hallmarks but also alleviates antagonistic hallmarks and ameliorates integrative hallmarks of aging,demonstrating dual effect and interconnected mechanisms.Notably,aberrant activa-tion in CK2 expression and activity are associated with various aging-related diseases,including cancer,cardiovascular diseases,chronic metabolic disorders,neurodegenerative diseases and skeletal degenera-tive conditions.Therefore,maintaining CK2 homeostasis may represent an effective strategy for delaying aging.This review summarizes the latest advances in CK2 and aging research,providing not only deeper insights into the common mechanisms underlying aging and aging-related diseases,but also a theoretical foundation for identifying potential targets for the early prevention of aging-related diseases.

Objective To investigate the biological functions of the ERG3 gene in Candida albicans and its potential value in antifungal therapy. Methods The ERG3 null mutant was constructed by the CRISPR/Cas9 technology. Gas chromatography-mass spectrometry, microbroth dilution method, hyphal induction and mouse systemic infection models were carried out to evaluate sterol metabolism, drug susceptibility, hyphal formation ability and pathogenicity in C. albicans. Results The disruption of the ERG3 gene led to disordered sterol metabolism in C. albicans with a significant increased level of episterol, 14α-methylfecosterol and ergosta-7,22-dienol. The ERG3 null mutant exhibited significantly reduced susceptibility to antifungal azole and polyene drugs, which suggested that ERG3 involve in regulating drug resistance. Although the disruption of ERG3 inhibited hyphal growth and biofilm formation, it did not significantly alter the pathogenicity of the strain in a mouse model of systemic fungal infection. Conclusion The ERG3 gene was a key regulator in the ergosterol synthesis pathway in C. albicans. Its deletion induced multi-drug resistance by reshaping sterol metabolism, while pathogenicity maintenance depended on compensatory mechanisms. This study provided critical insights for developing antifungal drugs targeting sterol metabolism and overcoming drug resistance.