AIM:This study aims to investigate the impact of TWIK-1 channels on abnormal pacemaker activi-ties induced by hypokalemia and to elucidate the underlying mechanisms.METHODS:The gene sequences encoding hu-man TWIK-1,specific TWIK-1 shRNA and TWIK-1-T118i mutant were synthesized and subsequently subcloned into lenti-viral vectors.To knock down the TWIK-1 gene in human induced pluripotent stem cell-derived cardiomyocytes(hiPSC-CMs),the cells were transduced with lentivirus carrying the specific TWIK-1 shRNA sequences.For the overexpression of TWIK-1 or the TWIK-1-T118i mutant in HL-1 mouse cardiomyocytes,the cells received lentiviral transduction containing the respective gene sequences.Patch-clamp techniques were employed to assess the effects of 1 mmol/L extracellular K+on the membrane potentials and whole-cell currents of the cardiomyocytes.RESULTS:Under conditions of 1 mmol/L extra-cellular K+,depolarization of membrane potentials was observed in the hiPSC-CMs and the HL-1 mouse cardiomyocytes ex-pressing human TWIK-1 channel,leading to the induction of abnormal pacemaker activities.This phenomenon could be reversibly abolished by the removal of extracellular Na+or inhibited through TWIK-1 knockdown.In contrast,the mem-brane potentials of HL-1 mouse cardiomyocytes expressing human TWIK-1-T118i mutant hyperpolarized,with no occur-rence of abnormal pacemaker activities.The hiPSC-CMs exhibiting abnormal pacemaker activities at 1 mmol/L extracellu-lar K+demonstrated TWIK-1-like Na+leak currents,which were blocked by quinine,a non-selective blocker of TWIK-1.CONCLUSION:The TWIK-1 channels play a critical role in the development of hypokalemia-induced abnormal pace-maker activities in human cardiomyocytes by facilitating Na+leak currents.

AIM:This study aims to investigate the impact of TWIK-1 channels on abnormal pacemaker activi-ties induced by hypokalemia and to elucidate the underlying mechanisms.METHODS:The gene sequences encoding hu-man TWIK-1,specific TWIK-1 shRNA and TWIK-1-T118i mutant were synthesized and subsequently subcloned into lenti-viral vectors.To knock down the TWIK-1 gene in human induced pluripotent stem cell-derived cardiomyocytes(hiPSC-CMs),the cells were transduced with lentivirus carrying the specific TWIK-1 shRNA sequences.For the overexpression of TWIK-1 or the TWIK-1-T118i mutant in HL-1 mouse cardiomyocytes,the cells received lentiviral transduction containing the respective gene sequences.Patch-clamp techniques were employed to assess the effects of 1 mmol/L extracellular K+on the membrane potentials and whole-cell currents of the cardiomyocytes.RESULTS:Under conditions of 1 mmol/L extra-cellular K+,depolarization of membrane potentials was observed in the hiPSC-CMs and the HL-1 mouse cardiomyocytes ex-pressing human TWIK-1 channel,leading to the induction of abnormal pacemaker activities.This phenomenon could be reversibly abolished by the removal of extracellular Na+or inhibited through TWIK-1 knockdown.In contrast,the mem-brane potentials of HL-1 mouse cardiomyocytes expressing human TWIK-1-T118i mutant hyperpolarized,with no occur-rence of abnormal pacemaker activities.The hiPSC-CMs exhibiting abnormal pacemaker activities at 1 mmol/L extracellu-lar K+demonstrated TWIK-1-like Na+leak currents,which were blocked by quinine,a non-selective blocker of TWIK-1.CONCLUSION:The TWIK-1 channels play a critical role in the development of hypokalemia-induced abnormal pace-maker activities in human cardiomyocytes by facilitating Na+leak currents.

OBJECTIVES: Uridine diphospho-N-acetylglucosamine 2-epimerase/N-acetylmannosamine kinase (GNE) myopathy is a progressive neurodegenerative disease associated with homozygous or compound heterozygous missense mutations in the GNE gene. This study aims to explore the impact of the homozygous p.V543M mutation in on cell phenotype and to gain preliminary insights into the underlying mechanisms. METHODS: Human embryonic kidney 293T (HEK 293T) cells were used to construct wild-type (WT-GNE) and mutant (MUT-GNE) GNE overexpression models. Western blotting and immunofluorescence were used to assess GNE protein expression levels and subcellular localization. Cell adhesion, proliferation, apoptosis, and mitochondrial membrane potential were evaluated using the cell counting kit-8 (CCK-8) assay, crystal violet staining, flow cytometry, Hoechst 33342/propidium iodide (PI) staining, and tetramethylrhodamine ethyl ester (TMRE) staining. Sialic acid synthesis levels and GNE enzymatic activity were measured, and the mRNA expression of sialic acid biosynthesis-related enzymes was quantified by real-time PCR. RESULTS: Western blotting confirmed successful establishment of GNE overexpression models. Immunofluorescence showed significantly reduced co-localization of GNE protein with Golgin-97 in the MUT-GNE group compared to WT-GNE (Pearson's correlation coefficient: 0.65±0.08 vs 0.83±0.06, P<0.05). Compared with WT-GNE, cells in the MUT-GNE group exhibited increased adhesion, decreased proliferation, and reduced mitochondrial membrane potential (P<0.05). No significant differences in apoptosis were observed between groups. The MUT-GNE group showed reduced sialic acid production, significantly decreased kinase activity, and downregulated transcription of sialic acid biosynthesis-related enzymes compared to WT-GNE (P<0.001). CONCLUSIONS The p.V543M mutation in the GNE gene alters cellular phenotype by reducing GNE enzymatic activity and the transcription of sialic acid biosynthesis enzymes, ultimately impairing sialic acid production.
Humans ; Mutation, Missense ; HEK293 Cells ; Apoptosis/genetics* ; Phenotype ; Multienzyme Complexes/metabolism* ; Cell Proliferation ; Homozygote ; Cell Adhesion/genetics* ; Distal Myopathies/genetics*

Transplantation-associated thrombotic microangiopathy（TA-TMA）is one of the severe complications after hematopoietic stem cell transplantation，and its specific pathogenesis has not yet been fully elucidated. In recent years，with in-depth research on TA-TMA，its pathogenesis has been gradually elucidated. It primarily involves multiple factors，including endothelial injury，aberrant activation of the complement system，and oxidative stress.Regarding treatment，in addition to conventional supportive therapy and etiology-directed management，various targeted therapies have emerged，including drugs like Eculizumab，recombinant thrombomodulin，defibrotide，and N-acetylcysteine.This article aims to systematically review the current research achievements and latest progress on the pathogenesis and treatment methods of TA-TMA，to provide references for the early prevention and treatment of TA-TMA.

AIM:To establish a physiological-based pharmacokinetic(PBPK)model of ertapen-em in elderly patients with chronic kidney disease,and to analyze the pharmacokinetic/pharmacody-namic index f％ T＞MIC at different doses.METH-ODS:The physicochemical properties and pharma-cokinetic characteristics of ertapenem were collect-ed by reviewing the literature and databases,and a healthy adult model was established in PKSim? software,and then extrapolated to the PBPK model of the elderly.The clinical pharmacokinetic re-search data were used to optimize and validate the model,and the mean folding error(MFE)was used as the index to evaluate the prediction perfor-mance of the model.The final model was used to simulate the in vivo exposure of elderly patients with chronic kidney disease after administration,and the pharmacokinetic/pharmacodynamic index of commonly used clinical dosing regimens was an-alyzed,and the recommended dosing regimens were given.RESULTS:The MFE of the area under the curve(AUC0-t),peak concentration(Cmax)and peak time(Tmmax)predicted by the established PBPK model of ertapenem in adults were 0.92,0.79 and 1.02,respectively,and the predicted value of the optimized PBPK model of ertapenem in the elderly was also consistent with the observed value of 0.5＜MFE＜2 standards,all of which have good predictive performance.With f％ T＞MIC greater than 40％as the drug efficacy target,the minimum inhibitory concentration(MIC)is 0.5-1 μg/mL for sensitive bacteria,and elderly patients with chronic kidney disease can consider reducing the drug dose as ap-propriate.CONCLUSION:The PBPK model of ertap-enem in elderly patients with renal insufficiency has been successfully established,and the model has good prediction performance and provides a reference for clinical personalized medication in el-derly patients with renal insufficiency.

AIM:To establish a physiological-based pharmacokinetic(PBPK)model of ertapen-em in elderly patients with chronic kidney disease,and to analyze the pharmacokinetic/pharmacody-namic index f％ T＞MIC at different doses.METH-ODS:The physicochemical properties and pharma-cokinetic characteristics of ertapenem were collect-ed by reviewing the literature and databases,and a healthy adult model was established in PKSim? software,and then extrapolated to the PBPK model of the elderly.The clinical pharmacokinetic re-search data were used to optimize and validate the model,and the mean folding error(MFE)was used as the index to evaluate the prediction perfor-mance of the model.The final model was used to simulate the in vivo exposure of elderly patients with chronic kidney disease after administration,and the pharmacokinetic/pharmacodynamic index of commonly used clinical dosing regimens was an-alyzed,and the recommended dosing regimens were given.RESULTS:The MFE of the area under the curve(AUC0-t),peak concentration(Cmax)and peak time(Tmmax)predicted by the established PBPK model of ertapenem in adults were 0.92,0.79 and 1.02,respectively,and the predicted value of the optimized PBPK model of ertapenem in the elderly was also consistent with the observed value of 0.5＜MFE＜2 standards,all of which have good predictive performance.With f％ T＞MIC greater than 40％as the drug efficacy target,the minimum inhibitory concentration(MIC)is 0.5-1 μg/mL for sensitive bacteria,and elderly patients with chronic kidney disease can consider reducing the drug dose as ap-propriate.CONCLUSION:The PBPK model of ertap-enem in elderly patients with renal insufficiency has been successfully established,and the model has good prediction performance and provides a reference for clinical personalized medication in el-derly patients with renal insufficiency.

A combined radiation-wound injury refers to a radiation injury combined with a traumatic wound, with the characteristics of repeated ulceration and a long and difficult healing process, which is a focus in the field of research on difficult-to-heal wounds. To research combined radiation-wound injuries, the establishment of animal models is a key part, and appropriate animal models are a guarantee of reliable experimental results. This review summarizes the current research progress on various animal models of combined radiation-wound injuries in terms of radiation types, animal species, and injury types and location, aiming to provide a scientific basis for establishing standardized animal models, studying injury mechanisms, and evaluating prevention and treatment efficacy for combined radiation-wound injuries.

Objective To perform the pharmacognostic identification of Anoectochilus lylei and establish the foundation for its accurate identification and further development. Methods The macroscopic identification and microscopic identification methods were used to identify A. lylei. Results A. lylei has ovate leaf shape, possessing red reticulated veins. Inverted flowers have Y-shaped and white lip. The anterior part of lip is two-lobed, and the lobes are linear-oblong. There are 1 to 3 shorts serrations on each side of the middle part of lip. Microscopic characteristics mainly show as follows: the cortex is broad in the transverse section of roots and stems; 1-5 and 1-7 vascular bundles in the xylem of transverse section of roots and stem, respectively. Collateral vascular bundle in the main veins of transverse section of leaves. There are multitudinous types of stomas in the leaf abaxial epidermis, most of which are anomocytic. Conclusion These characteristics could provide reference for the correct identification of A. lylei.

Objective:To explore the clinical effectiveness of an automatic computer-aided diagnosis(CAD) method in benign and malignant breast masses discrimination.Methods:The ultrasound images of 539 patients from the Second Hospital of Harbin Medical University and the Second Hospital of Hebei Medical University between 2012 to 2019 were analyzed retrospectively. According to the fifth Breast Imaging Reporting and Data System (BI-RADS), four breast radiologists first sent the case into a BI-RADS category with the original ultrasound image. Then with the CAD result, radiologists gave a category again. Pathology results and clinical data were not available to the radiologists during the diagnosis process. The histological and follow-up results were used as the gold standard. The accuracy of CAD automatic classification, radiologists′ diagnosis before and after CAD application were compared using the ROC curves. The accuracy, sensitivity and specificity of the diagnosis were also calculated.Results:The classification algorithm has a good performance in benign and malignant breast masses discrimination.When the cutoff value was 0.495, the accuracy, sensitivity and specificity were 0.878, 0.868 and 0.886 respectively. When the cutoff value was 0.203, the sensitivity and specificity was 0.981 and 0.337 respectively. With the CAD method, the radiologists improved their diagnostic performance. The total area under the ROC curve for the four radiologists increased from 0.775 to 0.871( P<0.001). The total sensitivity increased from 0.786 to 0.842, and the specificity increased from 0.681 to 0.813. Conclusions:The automatic classification algorithm in this study provides quantitative reference for doctors′ diagnosis. It has the potential to improve junior radiologists′ diagnostic performance in differentiating benign and malignant breast masses.

Objective:To explore the effect of introducing mixed reality technology into traditional atlas teaching to teach airway anatomy under bronchoscopy.Methods:A total of 30 Batch 2017 fifth-year clinical medicine students from Shanghai Jiao Tong University School of Medicine were randomly divided into control group and test group by RAND function in Excel, with 15 students in each group. The control group was taught with the traditional bronchoscopic atlas teaching, and the test group was combined with mixed reality technology. The two groups had the same class time. After teaching, the teaching effect was evaluated by examination and evaluation questionnaire. SPSS 25.0 software was conducted for t test and Mann-Whitney U test. Results:The average score after teaching of test group was (61.67±20.15), and that of control group was (36.67±13.32), with statistically significant differences ( t=4.01, P<0.001). According to the questionnaire results, the scores of the test group on course understanding, course concentration, participation, mastery and satisfaction were better than those of the control group, and the differences were statistically significant ( P<0.05). Conclusion:Using mixed reality technology to assist the clinical teaching of airway anatomy under bronchoscopy can improve the quality of students' study and enhance their understanding of the teaching content and students' participation passion, achieving better teaching effect.