AIM:To investigate the impact of Kir2.1 channels on abnormal spontaneous pacemaker activities induced by hypokalemia and to elucidate the underlying mechanisms.METHODS:Human induced pluripotent stem cell-derived cardiomyocytes(hiPSC-CMs)were transfected with lentiviral particles containing sequences for human Kir2.1,the Kir2.1-E224G mutant,or Kir4.1.Patch clamp techniques were employed to examine the effects of low extracellular potassium concentration([K+]e)of 1 mmol/L on the resting membrane potentials and whole-cell currents of the cells in each group,assessed via both current and voltage clamp modes.RESULTS:Under conditions of 1 mmol/L[K+]e,cur-rent clamp data revealed that hiPSC-CMs overexpressing Kir2.1 channels exhibited both hyperpolarized and depolarized resting membrane potentials,with the depolarized state triggering abnormal pacemaker activities.In contrast,cells overex-pressing the Kir2.1-E224G mutant or Kir4.1 channels displayed only hyperpolarized resting membrane potentials.Voltage clamp analysis indicated that hiPSC-CMs overexpressing Kir2.1 channels produced"N"-shaped whole-cell currents,whereas cells expressing the Kir2.1-E224G mutant or Kir4.1 exhibited typical K+currents.CONCLUSION:Kir2.1 channels play a crucial role in mediating hypokalemia-induced abnormal spontaneous pacemaker activities in human car-diomyocytes through their inward rectification properties.

Animal models combining disease and syndrome are important research tools to explore the nature of traditional Chinese medicine (TCM) syndromes. At present, the construction and evaluation methods of animal models have preliminarily established the foundation for standardized development. Qi-yin deficiency syndrome is a common type of TCM syndrome in cardiovascular diseases. It is an important pathogenic factor causing the onset, pathological damage, and chronic nature of cardiovascular diseases, as well as triggering other illnesses. The establishment of an animal model of cardiovascular disease with the characteristics of Qi-yin deficiency, along with an objective and standardized evaluation system, has become an important part of modern cardiovascular disease research. In recent years, research on the construction and evaluation of animal models of heart Qi-yin deficiency syndrome has increased, but the construction methods and evaluation criteria vary. Compared with other animal models, the literature is limited, lacking statistics and overall analysis. Therefore, based on the scientific connotation of heart Qi-yin deficiency syndrome, this article systematically reviews the evaluation system of its animal model, covering multidimensional methods such as macroscopic characterization assessment, physicochemical indicators and objective evaluation, and syndrome differentiation based on prescriptions. The specific model construction strategies are described, including single-factor induction methods (sleep deprivation, chronic intermittent hypoxia, arterial occlusion, high-salt feeding) and the compound-factor induction methods (sleep deprivation combined with drug method, chronic intermittent hypoxia combined with drug method, exhaustive swimming combined with drug method). Meanwhile, application examples of each model in the research are listed, the existing problems in the current model construction and evaluation are analyzed, and optimization directions are proposed, such as promoting the compound factor induction strategy and improving the objectivity of the evaluation criteria. This article aims to provide theoretical references for constructing an animal model of heart Qi-yin deficiency syndrome that conforms to TCM characteristics, and thereby laying a scientific foundation for the prevention and treatment of cardiovascular diseases with TCM.

Objective To observe the difference of bone micro-structure in different regions of proximal femur,micro-CT scanning was performed on 30 proximal femur specimens to explain the mechanism of proximal femur fracture and to provide anatomical basis for prosthesis design.Methods Totally 30 intact proximal femur specimens were obtained from 60-80 year-old cadavers.Micro-CT scanning was used to measure the trabecular thickness(Tb.Th),trabecular number(Tb.N),trabecular space(Tb.Sp),connectivity(Conn)and bone mineral density(BMD)and other parameters in 7 regions of proximal femur,including proximal pressure trabecular(PPT),distal pressure trabecular(DPT),femoral head-neck junction(FHNJ),head and neck of femoral neck(HNFN),the base of femoral neck(BPFN),intertrochanteric line(IL)and greater trochanter(GT).Results The bone mineral density of IL and GT were higher than those of BPFN,FHNJ,DPT and PPT.The trabecular thickness of GT was the largest,followed by IL,BPFN and HNFN,and the smallest was FHNJ,DPT and PPT.The trabecular space of IL was larger than that of GT,and the data of both were larger than those of other parts,among which DPT and PPT were the smallest.The trabecular number of IL and GT were the smallest,BPFN,HNFN and FHNJ were larger,and DPT was the largest.The volume fraction of IL was the smallest,BPFN and HNFN were larger,DPT and PPT were the largest.Conclusion The bone density,trabecular thickness,bone volume,and total volume of GT and IL in the proximal femur of elderly patients are all relatively large,so the reason for the high incidence of fractures is not due to weak internal bone microstructure;The bone density,trabecular thickness,and trabecular gap at the proximal and distal ends of the vertical trabecular bone are relatively small.If it is necessary to perform core decompression for prosthesis filling at this location,the design should be conducive to the mechanical conduction of the prosthesis and the regeneration of surrounding bone tissue.

Objective:To analyze the underlying causes of low-value medical behaviors for tumor from the decision-making perspectives of both physicians and patients,and propose targeted intervention strategies to mitigate the incidence of low-value medical decisions in tumor.Methods:The theories and methods of behavioral economics are applied to investigate how cognitive and behavioral biases between physicians and patients contribute to irrational medical decisions in low-value medical decision-making.Additionally,a low-value medical decision-making model is developed from the perspective of both physicians and patients.Results:Physicians may be influenced by behavioral economic theories such as loss aversion,availability heuristic,and framing effects during the decision-making process,leading to deviations from optimal rationality.Patients with tumor or their families,constrained by bounded rationality,often lack adequate treatment information and prioritize short-term survival extension as a primary decision anchor,thereby exacerbating the prevalence of low-value medical decisions.Conclusion:Interventions targeting both physicians and patients should focus on enhancing incentive mechanisms,promoting information sharing,correcting behavioral biases,and providing decision support tools to reduce the occurrence of low-value treatment decisions in tumor care.

Objective To investigate the mechanism of serine protease inhibitor A3N(SerpinA3N)in alleviating reti-nal neural injury in diabetic mice by inhibiting Müller cell inflammation.Methods Thirty-six db/db mice(72 eyes)were randomly divided into the db/db group,the db/db+SerpinA3N-overexpressing adeno-associated virus(AAV-SerpinA3N)group,and the db/db+empty vector adeno-associated virus(NC-SerpinA3N)group,with 12 mice in each group.Twelve age-matched healthy male littermate mice were randomly selected as the healthy control group(db/m group).Mice in each group were sacrificed 4 weeks after the corresponding treatments.Immunofluorescence staining was used to detect the co-localization of SerpinA3N and glial fibrillary acidic protein(GFAP)in the mouse retina.Hematoxylin-eosin(HE)staining was used to observe histopathological changes in the retinal tissue.TUNEL staining was used to detect the apoptosis of reti-nal ganglion cells(RGCs).Immunohistochemistry was used to detect GFAP expression.ELISA was used to measure the levels of inflammatory factors[interleukin(IL)-1 β,IL-6,IL-18,and tumor necrosis factor-α(TNF-α)]in the retinal tis-sue.The predicted target genes of SerpinA3N were imported into the STRING database to construct a protein-protein inter-action(PPI)network.The highest-scoring target was selected based on the scores for molecular docking.Western blot was used to detect the expression levels of SerpinA3N,nuclear factor kappa B(NF-κB),and spleen focus-forming virus proviral integration oncogene(Spi1)proteins in the retinal tissue.Results Immunofluorescence staining showed co-lo-calized expression of SerpinA3N and GFAP in the retinal tissue.Compared with the db/m group,the db/db,db/db+NC-SerpinA3N,and db/db+AAV-SerpinA3N groups showed decreased retinal thickness and RGC count,and increased number of TUNEL-positive cells,relative GFAP-positive expression intensity,levels of all inflammatory factors,and expression lev-els of NF-κB and Spi1 proteins,while SerpinA3N protein expression was decreased(all P＜0.05).Compared with the db/db group,the db/db+AAV-SerpinA3N group showed increased retinal thickness and RGC count,and decreased number of TUNEL-positive cells,relative GFAP-positive expression intensity,levels of all inflammatory factors,and expression levels of NF-κB and Spi1 proteins,while SerpinA3N protein expression was increased(all P＜0.05).Compared with the db/db+AAV-SerpinA3N group,the db/db+NC-SerpinA3N group showed decreased retinal thickness and RGC count,and increased number of TUNEL-positive cells,relative GFAP-positive expression intensity,levels of all inflammatory factors,and ex-pression levels of NF-κB and Spi1 proteins,while SerpinA3N protein expression was decreased(all P＜0.05).The PPI re-sults indicated an interaction between SerpinA3N and Spi1.Molecular docking results showed that Spi1 could form hydro-gen bonds with residues surrounding SerpinA3N.Conclusion Overexpression of SerpinA3N can inhibit Müller cell in-flammation and ameliorate retinal neural injury in diabetic mice,and the mechanism may be associated with the inhibition of the Spi1/NF-κB signaling pathway.

AIM:To investigate the impact of Kir2.1 channels on abnormal spontaneous pacemaker activities induced by hypokalemia and to elucidate the underlying mechanisms.METHODS:Human induced pluripotent stem cell-derived cardiomyocytes(hiPSC-CMs)were transfected with lentiviral particles containing sequences for human Kir2.1,the Kir2.1-E224G mutant,or Kir4.1.Patch clamp techniques were employed to examine the effects of low extracellular potassium concentration([K+]e)of 1 mmol/L on the resting membrane potentials and whole-cell currents of the cells in each group,assessed via both current and voltage clamp modes.RESULTS:Under conditions of 1 mmol/L[K+]e,cur-rent clamp data revealed that hiPSC-CMs overexpressing Kir2.1 channels exhibited both hyperpolarized and depolarized resting membrane potentials,with the depolarized state triggering abnormal pacemaker activities.In contrast,cells overex-pressing the Kir2.1-E224G mutant or Kir4.1 channels displayed only hyperpolarized resting membrane potentials.Voltage clamp analysis indicated that hiPSC-CMs overexpressing Kir2.1 channels produced"N"-shaped whole-cell currents,whereas cells expressing the Kir2.1-E224G mutant or Kir4.1 exhibited typical K+currents.CONCLUSION:Kir2.1 channels play a crucial role in mediating hypokalemia-induced abnormal spontaneous pacemaker activities in human car-diomyocytes through their inward rectification properties.

Objective To investigate the mechanism of serine protease inhibitor A3N(SerpinA3N)in alleviating reti-nal neural injury in diabetic mice by inhibiting Müller cell inflammation.Methods Thirty-six db/db mice(72 eyes)were randomly divided into the db/db group,the db/db+SerpinA3N-overexpressing adeno-associated virus(AAV-SerpinA3N)group,and the db/db+empty vector adeno-associated virus(NC-SerpinA3N)group,with 12 mice in each group.Twelve age-matched healthy male littermate mice were randomly selected as the healthy control group(db/m group).Mice in each group were sacrificed 4 weeks after the corresponding treatments.Immunofluorescence staining was used to detect the co-localization of SerpinA3N and glial fibrillary acidic protein(GFAP)in the mouse retina.Hematoxylin-eosin(HE)staining was used to observe histopathological changes in the retinal tissue.TUNEL staining was used to detect the apoptosis of reti-nal ganglion cells(RGCs).Immunohistochemistry was used to detect GFAP expression.ELISA was used to measure the levels of inflammatory factors[interleukin(IL)-1 β,IL-6,IL-18,and tumor necrosis factor-α(TNF-α)]in the retinal tis-sue.The predicted target genes of SerpinA3N were imported into the STRING database to construct a protein-protein inter-action(PPI)network.The highest-scoring target was selected based on the scores for molecular docking.Western blot was used to detect the expression levels of SerpinA3N,nuclear factor kappa B(NF-κB),and spleen focus-forming virus proviral integration oncogene(Spi1)proteins in the retinal tissue.Results Immunofluorescence staining showed co-lo-calized expression of SerpinA3N and GFAP in the retinal tissue.Compared with the db/m group,the db/db,db/db+NC-SerpinA3N,and db/db+AAV-SerpinA3N groups showed decreased retinal thickness and RGC count,and increased number of TUNEL-positive cells,relative GFAP-positive expression intensity,levels of all inflammatory factors,and expression lev-els of NF-κB and Spi1 proteins,while SerpinA3N protein expression was decreased(all P＜0.05).Compared with the db/db group,the db/db+AAV-SerpinA3N group showed increased retinal thickness and RGC count,and decreased number of TUNEL-positive cells,relative GFAP-positive expression intensity,levels of all inflammatory factors,and expression levels of NF-κB and Spi1 proteins,while SerpinA3N protein expression was increased(all P＜0.05).Compared with the db/db+AAV-SerpinA3N group,the db/db+NC-SerpinA3N group showed decreased retinal thickness and RGC count,and increased number of TUNEL-positive cells,relative GFAP-positive expression intensity,levels of all inflammatory factors,and ex-pression levels of NF-κB and Spi1 proteins,while SerpinA3N protein expression was decreased(all P＜0.05).The PPI re-sults indicated an interaction between SerpinA3N and Spi1.Molecular docking results showed that Spi1 could form hydro-gen bonds with residues surrounding SerpinA3N.Conclusion Overexpression of SerpinA3N can inhibit Müller cell in-flammation and ameliorate retinal neural injury in diabetic mice,and the mechanism may be associated with the inhibition of the Spi1/NF-κB signaling pathway.

Objective:To analyze the underlying causes of low-value medical behaviors for tumor from the decision-making perspectives of both physicians and patients,and propose targeted intervention strategies to mitigate the incidence of low-value medical decisions in tumor.Methods:The theories and methods of behavioral economics are applied to investigate how cognitive and behavioral biases between physicians and patients contribute to irrational medical decisions in low-value medical decision-making.Additionally,a low-value medical decision-making model is developed from the perspective of both physicians and patients.Results:Physicians may be influenced by behavioral economic theories such as loss aversion,availability heuristic,and framing effects during the decision-making process,leading to deviations from optimal rationality.Patients with tumor or their families,constrained by bounded rationality,often lack adequate treatment information and prioritize short-term survival extension as a primary decision anchor,thereby exacerbating the prevalence of low-value medical decisions.Conclusion:Interventions targeting both physicians and patients should focus on enhancing incentive mechanisms,promoting information sharing,correcting behavioral biases,and providing decision support tools to reduce the occurrence of low-value treatment decisions in tumor care.

Objective To investigate the advantages and efficacy of traction with titanium clips in endoscopic submucosal dissection(ESD)for large laterally spreading tumor(LST)in rectum and sigmoid colon.Methods 67 patients with large sigmoid or rectal LST underwent ESD from January 2018 to June 2022 were analyzed retrospectively,including 32 patients in Group A and 35 patients in Group B.Group A was treated with clip-line traction and group B was treated with traditional ESD.The size of lesion,the total operation time,the submucosal dissection time,submucosal dissection rate,submucosal injection number,en bloc resection rate,R0 resection rate,curative resection rate and complications of the two groups were compared.Results LST-G-M was the most common type and villous adenoma was the main pathology in both groups.There were no differences in en bloc resection rate,R0 resection rate and incidence of complications between the two groups.The average size of group A was(13.6±8.4)cm2,significantly larger than that in group B(9.3±4.7)cm2,the total operation time was(42.3±10.3)min in group A,significantly shorter than that in group B(47.9±10.1)min,submucosal dissection time was(30.7±8.2)min in group A,significantly shorter than that in group B(36.1±7.6)min,submucosal injection number was(2.7±1.1)times in group A,significantly less than that in group B(3.5±1.2)times,submucosal dissection rate was(0.4±0.2)cm2/min in group A,significantly faster than that in group B(0.2±0.1)cm2/min,the differences were statistically significant(P<0.05).Conclusion Compared with traditional ESD,clip-line traction can provide a better surgical field and more effective dissection for large LST in rectum and sigmoid colon.

After the characteristics of project-driven teaching methods and traditional teaching methods were com-paratively analyzed,a new gradient and hierarchical "dual-driven" model of medical interdisciplinary innovative informationists training was established by embedding the general model of project-driven teaching methods into the traditional training model of medical interdisciplinary innovative informationists training in order to improve the teaching level and find a new way for medical informationists training.