Objective To establish a purification,enrichment and test method of tetrodotoxin in blood.Methods Through the investigation of various hydrophilic chromatographic columns,the comparison of extraction effects of different types of solid phase extraction columns and the interference analysis of mixed peaks on qualitative ion pairs,the matrix influence of tetrodotoxin was reduced,and the detection sensitivity and qualitative accuracy were improved.Results Tetrodotoxin is highly polar and easily inhibited by the matrix,while conventional precipitation protein method has low sensitivity and isomer double peaks,and the C18 column is not reserved.After comprehensive comparative analysis,the weak cation exchange column PWC column is finally used for purification and enrichment.Complete elution was achieved using 0.5 mL 10%formic acid and 50%acetonitrile aqueous solution.Seperation was performed on an Atlantis HILIC column,with qualitative ion pairs set at m/z,320.10>162.15 and 284.15.The detection limit of the method was 0.061 ng/mL.Conclusion The established PWC solid-phase extraction-LC/MS detection method demonstrates significant purification efficacy,minimal matrix influence,unobstructed chromatographic peaks,markedly improved detection sensitivity.This approach is operationally simple,and applicable to forensic casework.

Diabetic cardiomyopathy (DCM) is a medical condition characterized by cardiac remodeling and dysfunction in individuals with diabetes mellitus. Sarcoplasmic reticulum (SR) and mitochondrial Ca²⁺ overload in cardiomyocytes have been recognized as biological hallmarks in DCM; however, the specific factors underlying these abnormalities remain largely unknown. In this study, we aimed to investigate the role of a cardiac-specific long noncoding RNA, D830005E20Rik (Trdn-as), in DCM. Our results revealed the remarkably upregulation of Trdn-as in the hearts of the DCM mice and cardiomyocytes treated with high glucose (HG). Knocking down Trdn-as in cardiac tissues significantly improved cardiac dysfunction and remodeling in the DCM mice. Conversely, Trdn-as overexpression resulted in cardiac damage resembling that observed in the DCM mice. At the cellular level, Trdn-as induced Ca²⁺ overload in the SR and mitochondria, leading to mitochondrial dysfunction. RNA-seq and bioinformatics analyses identified calsequestrin 2 (Casq2), a primary calcium-binding protein in the junctional SR, as a potential target of Trdn-as. Further investigations revealed that Trdn-as facilitated the recruitment of METTL14 to the Casq2 mRNA, thereby enhancing the m⁶A modification of Casq2. This modification increased the stability of Casq2 mRNA and subsequently led to increased protein expression. When Casq2 was knocked down, the promoting effects of Trdn-as on Ca²⁺ overload and mitochondrial damage were mitigated. These findings provide valuable insights into the pathogenesis of DCM and suggest Trdn-as as a potential therapeutic target for this condition.
Animals ; Diabetic Cardiomyopathies/pathology* ; RNA, Long Noncoding/genetics* ; Myocytes, Cardiac/metabolism* ; Mice ; Calsequestrin/genetics* ; Calcium/metabolism* ; Male ; Sarcoplasmic Reticulum/metabolism* ; Methyltransferases/metabolism* ; Mice, Inbred C57BL ; Mitochondria, Heart/metabolism* ; Disease Models, Animal ; Mitochondria/metabolism*

Objective:To explore the molecular mechanism by which the methionine adenosyltransferase 2A (MAT2A)/β-catenin/zinc finger E-box binding homeobox 1 (ZEB1)/epithelial-mesenchymal transition (EMT) pathway regulates neural tube defect (NTD) through intracellular S-adenosylmethionine (SAM).Methods:A mouse NTD model was induced using the SAM metabolic disorder inhibitor ethionine. Eighty specific pathogen-free C57BL/6 mice were divided into three groups: a normal group (36 mice), an ethionine group (46 mice), and an ethionine+SAM group (44 mice). Phosphate-buffered saline (PBS), ethionine, and ethionine+SAM were respectively injected intraperitoneally on embryonic day 7.5 (E7.5), and the mice were sacrificed on E10.5. Embryonic tissues were collected, and the morphology of embryos in each group was observed under a stereomicroscope. The interaction between ethionine and MAT2A was analyzed using Autodock software. The expression levels of MAT2A, β-catenin, ZEB1, and EMT-related proteins in the brain tissues of embryos from the three groups were measured using immunofluorescence, immunohistochemistry, Western blotting, enzyme-linked immunosorbent assay (ELISA), and real-time quantitative polymerase chain reaction (RT-qPCR). Variance analysis was used for intergroup comparisons.Results:(1) Autodock analysis results showed that MAT2A binds to ethionine through covalent bonds, exhibiting a complementary effect, thereby accelerating the expression of MAT2A. (2) After successful construction of the NTD model, normal embryos were plump with well-developed brains. NTD embryos showed delayed development, obvious anencephaly, unclosed neural tubes, and asymmetry. (3) The levels of SAM and SAH in the embryonic tissues of the ethionine group were significantly lower than those in the normal group (1 737.56±95.64 vs. 872.33±205.11, and 89.17±9.50 vs. 51.25±9.48, respectively). The SAM and SAH levels in the ethionine+SAM group was 1 197.00±222.27 and 66.61±12.25, significantly higher than those in the ethionine group ( P<0.017). Compared with the normal group and the ethionine+SAM group, the expression of MAT2A mRNA in the embryonic brain tissue of the ethionine group was significantly upregulated (1.00±0.00, 1.59±0.52, and 2.42±0.53, respectively, F=49.64, P<0.001; pairwise comparisons between groups P<0.017). (4) Compared with the normal group, the expression of Ctnnb1 in the ethionine group was reduced, and the expression of Ctnnb1 in the ethionine+SAM group was higher than that in the ethionine group (1.00±0.00, 0.38±0.16, and 0.76±0.10, respectively, F=149.03, P<0.001; pairwise comparisons between groups P<0.017). (5) The expression of ZEB1 in the ethionine group was higher than that in the normal group and the ethionine+SAM group (2.91±0.55, 1.00±0.00, and 1.61±0.20, respectively, F=150.01, P<0.001; pairwise comparisons between groups P<0.017). (6) The expression levels of E-cadherin and Vimentin in the ethionine group were lower than those in the normal group. In contrast, the expression of N-cadherin was higher than that in the normal group. After SAM supplementation, the expression levels of E-cadherin and Vimentin were upregulated, and the expression level of N-cadherin was downregulated (0.54±0.12, 1.00±0.00, and 0.72±0.14, respectively, F=87.44; 0.53±0.17, 1.00±0.00, and 0.76±0.09, F=87.44; 3.11±0.53, 1.00±0.00, and 2.13±0.56, F=95.54; all P<0.001; pairwise comparisons within the same index group P<0.017]). Conclusions:Ethionine promotes the expression of MAT2A, leading to reduced SAM production. Ethionine regulates the level of ZEB1 by increasing MAT2A and inhibits the EMT process to interfere with methionine cycle metabolism, ultimately resulting in NTD.

Myocardial fibrosis is a serious cause of heart failure and even sudden cardiac death. However, the mechanisms underlying myocardial ischemia-induced cardiac fibrosis remain unclear. Here, we identified that the expression of sterile alpha and TIR motif containing 1 (SARM1), was increased significantly in the ischemic cardiomyopathy patients, dilated cardiomyopathy patients (GSE116250) and fibrotic heart tissues of mice. Additionally, inhibition or knockdown of SARM1 can improve myocardial fibrosis and cardiac function of myocardial infarction (MI) mice. Moreover, SARM1 fibroblasts-specific knock-in mice had increased deposition of extracellular matrix and impaired cardiac function. Mechanically, elevated expression of SARM1 promotes the deposition of extracellular matrix by directly modulating P4HA1. Notably, by using the Click-iT reaction, we identified that the increased expression of ZDHHC17 promotes the palmitoylation levels of SARM1, thereby accelerating the fibrosis process. Based on the fibrosis-promoting effect of SARM1, we screened several drugs with anti-myocardial fibrosis activity. In conclusion, we have unveiled that palmitoylated SARM1 targeting P4HA1 promotes collagen deposition and myocardial fibrosis. Inhibition of SARM1 is a potential strategy for the treatment of myocardial fibrosis. The sites where SARM1 interacts with P4HA1 and the palmitoylation modification sites of SARM1 may be the active targets for anti-fibrosis drugs.

Cardiac fibrosis is characterized by an elevated amount of extracellular matrix (ECM) within the heart. However, the persistence of cardiac fibrosis ultimately diminishes contractility and precipitates cardiac dysfunction. Circular RNAs (circRNAs) are emerging as important regulators of cardiac fibrosis. Here, we elucidate the functional role of a specific circular RNA CELF1 in cardiac fibrosis and delineate a novel feedback loop mechanism. Functionally, circ-CELF1 was involved in enhancing fibrosis-related markers' expression and promoting the proliferation of cardiac fibroblasts (CFs), thereby exacerbating cardiac fibrosis. Mechanistically, circ-CELF1 reduced the ubiquitination-degradation rate of BRPF3, leading to an elevation of BRPF3 protein levels. Additionally, BRPF3 acted as a modular scaffold for the recruitment of histone acetyltransferase KAT7 to facilitate the induction of H3K14 acetylation within the promoters of the Celf1 gene. Thus, the transcription of Celf1 was dramatically activated, thereby inhibiting the subsequent response of their downstream target gene Smad7 expression to promote cardiac fibrosis. Moreover, Celf1 further promoted Celf1 pre-mRNA transcription and back-splicing, thereby establishing a feedback loop for circ-CELF1 production. Consequently, a novel feedback loop involving CELF1/circ-CELF1/BRPF3/KAT7 was established, suggesting that circ-CELF1 may serve as a potential novel therapeutic target for cardiac fibrosis.

Objective To establish a purification,enrichment and test method of tetrodotoxin in blood.Methods Through the investigation of various hydrophilic chromatographic columns,the comparison of extraction effects of different types of solid phase extraction columns and the interference analysis of mixed peaks on qualitative ion pairs,the matrix influence of tetrodotoxin was reduced,and the detection sensitivity and qualitative accuracy were improved.Results Tetrodotoxin is highly polar and easily inhibited by the matrix,while conventional precipitation protein method has low sensitivity and isomer double peaks,and the C18 column is not reserved.After comprehensive comparative analysis,the weak cation exchange column PWC column is finally used for purification and enrichment.Complete elution was achieved using 0.5 mL 10%formic acid and 50%acetonitrile aqueous solution.Seperation was performed on an Atlantis HILIC column,with qualitative ion pairs set at m/z,320.10>162.15 and 284.15.The detection limit of the method was 0.061 ng/mL.Conclusion The established PWC solid-phase extraction-LC/MS detection method demonstrates significant purification efficacy,minimal matrix influence,unobstructed chromatographic peaks,markedly improved detection sensitivity.This approach is operationally simple,and applicable to forensic casework.

Objective:To explore the molecular mechanism by which the methionine adenosyltransferase 2A (MAT2A)/β-catenin/zinc finger E-box binding homeobox 1 (ZEB1)/epithelial-mesenchymal transition (EMT) pathway regulates neural tube defect (NTD) through intracellular S-adenosylmethionine (SAM).Methods:A mouse NTD model was induced using the SAM metabolic disorder inhibitor ethionine. Eighty specific pathogen-free C57BL/6 mice were divided into three groups: a normal group (36 mice), an ethionine group (46 mice), and an ethionine+SAM group (44 mice). Phosphate-buffered saline (PBS), ethionine, and ethionine+SAM were respectively injected intraperitoneally on embryonic day 7.5 (E7.5), and the mice were sacrificed on E10.5. Embryonic tissues were collected, and the morphology of embryos in each group was observed under a stereomicroscope. The interaction between ethionine and MAT2A was analyzed using Autodock software. The expression levels of MAT2A, β-catenin, ZEB1, and EMT-related proteins in the brain tissues of embryos from the three groups were measured using immunofluorescence, immunohistochemistry, Western blotting, enzyme-linked immunosorbent assay (ELISA), and real-time quantitative polymerase chain reaction (RT-qPCR). Variance analysis was used for intergroup comparisons.Results:(1) Autodock analysis results showed that MAT2A binds to ethionine through covalent bonds, exhibiting a complementary effect, thereby accelerating the expression of MAT2A. (2) After successful construction of the NTD model, normal embryos were plump with well-developed brains. NTD embryos showed delayed development, obvious anencephaly, unclosed neural tubes, and asymmetry. (3) The levels of SAM and SAH in the embryonic tissues of the ethionine group were significantly lower than those in the normal group (1 737.56±95.64 vs. 872.33±205.11, and 89.17±9.50 vs. 51.25±9.48, respectively). The SAM and SAH levels in the ethionine+SAM group was 1 197.00±222.27 and 66.61±12.25, significantly higher than those in the ethionine group ( P<0.017). Compared with the normal group and the ethionine+SAM group, the expression of MAT2A mRNA in the embryonic brain tissue of the ethionine group was significantly upregulated (1.00±0.00, 1.59±0.52, and 2.42±0.53, respectively, F=49.64, P<0.001; pairwise comparisons between groups P<0.017). (4) Compared with the normal group, the expression of Ctnnb1 in the ethionine group was reduced, and the expression of Ctnnb1 in the ethionine+SAM group was higher than that in the ethionine group (1.00±0.00, 0.38±0.16, and 0.76±0.10, respectively, F=149.03, P<0.001; pairwise comparisons between groups P<0.017). (5) The expression of ZEB1 in the ethionine group was higher than that in the normal group and the ethionine+SAM group (2.91±0.55, 1.00±0.00, and 1.61±0.20, respectively, F=150.01, P<0.001; pairwise comparisons between groups P<0.017). (6) The expression levels of E-cadherin and Vimentin in the ethionine group were lower than those in the normal group. In contrast, the expression of N-cadherin was higher than that in the normal group. After SAM supplementation, the expression levels of E-cadherin and Vimentin were upregulated, and the expression level of N-cadherin was downregulated (0.54±0.12, 1.00±0.00, and 0.72±0.14, respectively, F=87.44; 0.53±0.17, 1.00±0.00, and 0.76±0.09, F=87.44; 3.11±0.53, 1.00±0.00, and 2.13±0.56, F=95.54; all P<0.001; pairwise comparisons within the same index group P<0.017]). Conclusions:Ethionine promotes the expression of MAT2A, leading to reduced SAM production. Ethionine regulates the level of ZEB1 by increasing MAT2A and inhibits the EMT process to interfere with methionine cycle metabolism, ultimately resulting in NTD.

Purpose/Significance To analyze the network security risk events monitored by the situational awareness platform of large hospitals,to find out the causes,and to put forward solutions and suggestions for improvement.Method/Process Taking the First Affiliated Hospital of Zhengzhou University as an example,the paper analyzes risk events on the situational awareness platform,screens the risky ter-minals on the hospital intranet,carries out rectification and reinforcement,analyzes the department distribution and causes of risky termi-nals,and puts forward suggestions for improvement.Result/Conclusion The number of risky terminals in medical and technical depart-ments is large,mainly due to the lack of management and the lack of full coverage of antivirus software.Through the rectification and rein-forcement of risky terminals,the number of network security risk events has been significantly reduced.Strengthening the hospital terminal security management,enhancing staff awareness of network security,and strengthening network security protection in different areas can ef-fectively reduce the incidence of hospital network security risk events and improve the hospital network security protection capability.

OBJECTIVE: The present study aimed to evaluate the therapeutic effect and explore the underlying mechanisms of Longxue Tongluo Capsule (LTC) on ischemic stroke rats. METHODS: Twenty-six rats were randomly divided into four groups, including sham group, sham + LTC group, MCAO group, and MCAO + LTC group. Ischemic stroke rats were simulated by middle cerebral artery occlusion (MCAO), and LTC treatment group were orally administrated with 300 mg/kg of LTC once daily for seven consecutive days. LTC therapy was validated in terms of neurobehavioral abnormality evaluation, cerebral infarct area, and histological assessments. The plasma metabolome comparisons amongst different groups were conducted by UHPLC-Q Exactive MS in combination with subsequent multivariate statistical analysis, aiming to finding the molecules in respond to the surgery or LTC treatment. RESULTS: Intragastric administration of LTC significantly decreased not only the neurobehavioral abnormality scores but also the cerebral infarct area of MCAO rats. The interstitial edema, atrophy, and pyknosis of glial and neuronal cells occurred in the infarcted area, core area, and marginal area of cerebral cortex were improved after LTC treatment. A total of 13 potential biomarkers were observed, and Youden index of 11 biomarkers such as LysoPC, SM, and PE were more than 0.7, which were involved in neuroprotective process. The correlation and pathway analysis showed that LTC was beneficial to ischemic stroke rats via regulating glycerophospholipid and sphingolipid metabolism, together with nicotinate and nicotinamide metabolism. Heatmap and ternary analysis indicated the synergistic effect of carbohydrates and lipids may be induced by flavonoid intake from LTC. CONCLUSION The present study could provide evidence that metabolomics, as systematic approach, revealed its capacity to evaluate the holistic efficacy of TCM, and investigate the molecular mechanism underlying the clinical treatment of LTC on ischemic stroke.

Objective:To investigate the clinical practice level and influencing factors of geriatric nursing specialist nurses.Methods:This study was a cross-sectional survey. Using the convenient sampling method, a total of 332 specialist nurses from 5 phases trained by Beijing Nursing Association from January to February 2021 were selected as the research objects. The general data questionnaire, Questionnaire on Clinical Practice Level of Geriatric Nursing Specialist Nurses, Questionnaire on Unit Support for Geriatric Nurses and Core Competence Self-Assessment Scale of Geriatric Nursing Specialist Nurses were used to investigate the nurses. Pearson correlation was used to analyze the relationship between unit support, self-assessment of core competence and practice level. Multiple linear regression was used to analyze the factors influencing the clinical practice level of geriatric nurses. A total of 332 questionnaires were distributed, 306 questionnaires were returned and 298 were valid questionnaires.Results:The total mean score of clinical practice of geriatric nursing specialist nurses was (3.42±0.83) . The results of multiple linear regression analysis showed that the work department, unit support and core competence were the influencing factors of the clinical practice level of geriatric nursing specialist nurses ( P<0.05) . Conclusions:Specialist nurses who work in the geriatric ward, have a high degree of unit support and have a high level of core competence have a higher clinical practice level.