ObjectiveJunctophilin-2 (JPH2) is an essential structural protein that maintains junctional membrane complexes (JMCs) in cardiomyocytes by tethering the plasma membrane to the sarcoplasmic reticulum, thereby facilitating excitation-contraction (E-C) coupling. Mutations in JPH2 have been associated with hypertrophic cardiomyopathy (HCM), but the molecular mechanisms governing its membrane-binding properties and the functional relevance of its membrane occupation and recognition nexus (MORN) repeat motifs remain incompletely understood. This study aimed to elucidate the structural basis of JPH2 membrane association and its implications for HCM pathogenesis. MethodsA recombinant N-terminal fragment of mouse JPH2 (residues1-440), encompassing the MORN repeats and an adjacent helical region, was purified under near-physiological buffer conditions.X-ray crystallography was employed to determine the structure of the JPH2 MORN-Helix domain. Sequence conservation analysis across species and junctophilin isoforms was performed to assess the evolutionary conservation of key structural features. Functional membrane-binding assays were conducted using liposome co-sedimentation and cell-based localization studies in COS7 and HeLa cells. In addition, site-directed mutagenesis targeting positively charged residues and known HCM-associated mutations, including R347C, was used to evaluate their effects on membrane interaction and subcellular localization. ResultsThe crystal structure of the mouse JPH2 MORN-Helix domain was resolved at 2.6 Å, revealing a compact, elongated architecture consisting of multiple tandem MORN motifs arranged in a curved configuration, forming a continuous hydrophobic core stabilized by alternating aromatic residues. A C-terminal α-helix further reinforced structural integrity. Conservation analysis identified the inner groove of the MORN array as a highly conserved surface, suggesting its role as a protein-binding interface. A flexible linker segment enriched in positively charged residues, located adjacent to the MORN motifs, was found to mediate direct electrostatic interactions with negatively charged phospholipid membranes. Functional assays demonstrated that mutation of these basic residues impaired membrane association, while the HCM-linked R347C mutation completely abolished membrane localization in cellular assays, despite preserving the overall MORN-Helix fold in structural modeling. ConclusionThis study provides structural insight into the membrane-binding mechanism of the cardiomyocyte-specific protein JPH2, highlighting the dual roles of its MORN-Helix domain in membrane anchoring and protein interactions. The findings clarify the structural basis for membrane targeting via a positively charged linker and demonstrate that disruption of this interaction—such as that caused by the R347C mutation—likely contributes to HCM pathogenesis. These results not only enhance current understanding of JPH2 function in cardiac E-C coupling but also offer a structural framework for future investigations into the assembly and regulation of JMCs in both physiological and disease contexts.

Aim To investigate the protective effect of Vaccarin(Va)on epithelial-mesenchymal transition(EMT)in renal fibrosis model mice through regulating STAT3,and the underlying mechanism.Methods Left ureter ligation was used to establish a mouse model of unilateral ureteral obstruction(UUO);human kid-ney tubular epithelial(HK2)cells were induced to differentiate by transforming growth factor-β(TGF-β)in vitro.HE and Masson staining were used to observe the morphological changes of renal tissue;kits were used to detect the levels of BUN,Cr,IL-1β and IL-7 in mouse serum;CCK-8 was used to detect the effect of Va on the viability of HK2 cells;RT-PCR was used to detect the levels of inflammatory factors in HK2 cells;Western blot was used to detect the expression of STAT3,p-STAT3,E-cadherin,and α-SMA proteins in renal tissue and HK2 cells;to further investigate the regulation of Va on STAT3,JAK/STAT3 pathway acti-vator RO8191 was used to treat TGF-β-induced HK2 cells,and functional loss was detected.Results Va improved the pathological damage in UUO mice,inhibi-ted the levels of BUN,Cr and inflammatory factors;Va inhibited the phosphorylation of STAT3,upregulated E-cadherin,and downregulated α-SMA protein expres-sion;RO8191 counteracted the inhibitory effect of Va on the phosphorylation of STAT3.Conclusions Va inhibits the phosphorylation of STAT3 and the release of inflammatory factors,improves EMT,thus exerting an anti-renal fibrosis effect.

The coil adverse events in the U.S.Food and Drug Administration Manufacturer and User Facility Device Experience(MAUDE)database from January 2021 to June 2024 were analyzed retrospectively.The risks of coils during the clinical application and their causes were explored with hospital survey and expert demonstration in Shandong Province.Some improving measures were put forward for the safe use of coils,including implementing the main responsibility of the registrant,enhancing the professional skills of the using institutions and strengthening the supervision of the supervisory authorities.[Chinese Medical Equipment Journal,2025,46(6):83-87]

BACKGROUND:In the occurrence and development of demyelinating diseases of the central nervous system,neuroinflammation caused by microglia is the main pathological feature,so inhibiting the inflammatory response is very important to alleviate demyelination.Hydroxysafflor yellow A can protect the blood-brain barrier,inhibit neuronal apoptosis,and improve neurological function.OBJECTIVE:To explore the mechanism of hydroxysafflor yellow A inhibiting bicyclohexanone oxalyl dihydrazone-induced demyelination in mice.METHODS:(1)In vivo:Thirty healthy male C57BL/6 mice were randomly divided into three groups:normal group,cuprizone group,and hydroxysafflor yellow A group.The mice in the cuprizone group and the hydroxysafflor yellow A group were fed with 0.2％cuprizone diet for 6 weeks to establish mouse models of demyelination.The mice in the normal group were fed with normal diet.At the end of the 4th week,the mice in the hydroxysafflor yellow A group were intraperitoneally injected with hydroxysafflor yellow A 20 mg/kg per day.The mice in the normal and cuprizone groups were intraperitoneally injected with normal saline for 2 weeks.The behavioral changes of mice were evaluated by open field test and elevated plus maze test.The loss of myelin sheath in corpus callosum was detected by black gold staining,myelin basic protein and degraded myelin basic protein immunofluorescence staining.The activation of microglia and the expression of inflammatory factors were detected by I ba-1 immunofluorescence staining and ELISA,respectively.The protein expression levels of Toll-like receptor 4,myeloid differentiation factor 88,and nuclear factor κB p65 in the brain of mice in each group were detected by western blot assay.(2)In vitro experiment:The inflammation model of BV2 microglia was established by lipopolysaccharide induction.BV2 cells were divided into normal group,lipopolysaccharide group(1 μg/mL),and lipopolysaccharide(1 μg/mL)+hydroxysafflor yellow A(25 μmol/L)group.The expression levels of tumor necrosis factor α and interleukin 6 in the supernatant were detected by ELISA.RESULTS AND CONCLUSION:(1)Compared with the normal group,the mice in the cuprizone group had severe anxiety,abnormal autonomic movement ability,and a large amount of myelin sheath loss in the corpus callosum.The average fluorescence intensity of myelin basic protein was significantly reduced,and the average fluorescence intensity of degraded myelin basic protein was significantly increased.The number of lba1+microglia increased,the contents of interleukin 1β,tumor necrosis factor α,and interleukin 6 in the brain increased,and the protein expression levels of Toll-like receptor 4,myeloid differentiation factor 88,and nuclear factor κB p65 increased significantly.The above symptoms and indexes of mice were reversed after hydroxysafflor yellow A treatment.(2)Hydroxysafflor yellow A significantly inhibited the expression of inflammatory factors such as tumor necrosis factor α,and interleukin 6 induced by lipopolysaccharide in BV2 microglia.(3)The above results demonstrate that hydroxysafflor yellow A can significantly improve cuprizone-induced demyelination in mice.The mechanism of action is related to the inhibition of microglial activation-mediated inflammatory response through the Toll-like receptor 4/myeloid differentiation factor 88/nuclear factor κB p65 signaling pathway.

BACKGROUND:The reduction of contact area,edge load,and stress increase of adjacent cartilage caused by knee cartilage defect are considered to easily cause degenerative changes in this tissue,which may develop into knee osteoarthritis.Growth factors are considered to be a treatment method to promote the healing of damaged cartilage and delay the progression of degenerative arthritis.OBJECTIVE:To analyze the hotspots and prospects of growth factor-promoted knee cartilage regeneration research by bibliometric methods.METHODS:The first author retrieved 321 articles related to growth factor-promoted knee cartilage regeneration research from the Web of Science core set database.VOSviewer 1.6.19 software was used to analyze the publication volume,country,institution,keyword,and literature citation status of the articles,and investigate the research hotspots.RESULTS AND CONCLUSION:(1)From 2000 to 2024,the annual number of publications in the field of growth factor-promoted knee cartilage regeneration showed an overall upward trend,with the highest number of publications in 2021.Harvard University in the United States published the most papers.(2)Keyword analysis showed that the frequency of keywords such as growth factor,cartilage,cartilage repair,platelet-rich plasma,and cartilage regeneration was high.In addition,the keyword co-occurrence network diagram showed that growth factor was closely related to keywords such as cartilage repair and cartilage regeneration,indicating that growth factor research plays an important role in the field of cartilage regeneration.(3)The results of literature citation analysis showed that the combination of platelet-rich plasma and muscle-derived stem cells may provide a new and effective treatment strategy for patients with osteoarthritis,which can deepen the understanding of cartilage repair mechanisms by promoting stem cell proliferation and cartilage formation.Fibroblast growth factor 2,fibroblast growth factor 18,and insulin growth factor 1 play a key role in cartilage repair and can promote chondrocyte proliferation and matrix synthesis.In particular,fibroblast growth factor 18 can promote the repair of damaged cartilage,thereby alleviating patients'pain and dysfunction,which deserves further in-depth study in the future.The latest research has developed a new Polyhedrin Delivery System(PODS)that can continuously release growth factors such as bone morphogenetic protein 2 and 7,significantly promoting chondrocyte proliferation and cartilage repair.This system provides a new perspective and potential therapy for the treatment of osteoarthritis.(4)Therefore,bone morphogenetic protein 2,7,insulin growth factor 1,and recombinant human fibroblast growth factor 18 are promising growth factor therapies for promoting cartilage regeneration.In the future,further in-depth research on the mechanism of action of growth factors,optimization of treatment strategies,and strengthening of long-term efficacy and safety evaluation are needed.

Aim To investigate the therapeutic effects of a newly developed Tadalafil tablet on pulmonary fi-brosis induced by paraquat(PQ)in rats,as well as its impact on histone acetylation levels in epithelial cells.Methods SD rats were randomly divided into four groups:the control group(control),the model group(PQ),the Tadalafil new tablet treatment group(N-Tad,1 mg·kg-1),and the positive control drug treatment group(Cialis,5 mg·kg-1).The model group and treatment group rats were intraperitoneally injected with PQ(30 mg·kg-1).Two hours after the initial treatment,the rats in the treatment group re-ceived N-Tad or Cialis via gavage,while the control and model groups were administered an equal volume of physiological saline by gavage once daily for 28 days.The weight gain rate and lung tissue index for each group of rats were calculated.Additionally,the effects of N-Tad treatment on lung tissue structural damage and collagen deposition in rats with PQ-in-duced pulmonary fibrosis were observed using HE stai-ning,Masson trichrome staining,and immunohisto-chemical techniques.By employing the Western blot technique,the effects of Tadalafil intervention on the expression of the epithelial marker E-cadherin(E-Cad),the stromal marker fibronectin(Fn),and the histone acetylation marker acetylated histones(Ac-his-tones)in A549 cells were observed.Results Com-pared to the control group,rats with PQ-induced pul-monary fibrosis exhibited a significant decrease in the rate of body weight growth,an increase in lung tissue index(P＜0.05),and a notable increase in the expression and distribution of the fibrosis marker alpha-smooth muscle actin(α-SMA)in lung tissue.The structure of the lung tissue was disrupted,accompanied by the deposition of interstitial collagen fibers.Both N-Tad and Cialis treatments could significantly enhance the rate of weight gain,decrease the lung tissue index,inhibit the expression of α-SMA,and reduce the depo-sition of interstitial collagen in the lung tissue of rats with pulmonary fibrosis.Notably,low-dose N-Tad treatment was comparable to high-dose Cialis treat-ment.At the cellular level,Tadalafil significantly in-hibited the high expression of Fn induced by transfor-ming growth factor beta 1(TGF-β1)in A549 cells.It also upregulated the expression of E-cadherin and sig-nificantly increased the levels of acetylated histones(P＜0.05).Conclusions N-Tad promotes histone acetylation in alveolar epithelial cells,significantly in-hibits epithelial-mesenchymal transition,increases E-cadherin expression,and improves lung tissue structur-al damage and collagen deposition caused by PQ.Ad-ditionally,it offers the advantage of a lower effective dose compared to Cialis,providing a new option for the treatment of pulmonary fibrosis.

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.

Aim To investigate the therapeutic effects of a newly developed Tadalafil tablet on pulmonary fi-brosis induced by paraquat(PQ)in rats,as well as its impact on histone acetylation levels in epithelial cells.Methods SD rats were randomly divided into four groups:the control group(control),the model group(PQ),the Tadalafil new tablet treatment group(N-Tad,1 mg·kg-1),and the positive control drug treatment group(Cialis,5 mg·kg-1).The model group and treatment group rats were intraperitoneally injected with PQ(30 mg·kg-1).Two hours after the initial treatment,the rats in the treatment group re-ceived N-Tad or Cialis via gavage,while the control and model groups were administered an equal volume of physiological saline by gavage once daily for 28 days.The weight gain rate and lung tissue index for each group of rats were calculated.Additionally,the effects of N-Tad treatment on lung tissue structural damage and collagen deposition in rats with PQ-in-duced pulmonary fibrosis were observed using HE stai-ning,Masson trichrome staining,and immunohisto-chemical techniques.By employing the Western blot technique,the effects of Tadalafil intervention on the expression of the epithelial marker E-cadherin(E-Cad),the stromal marker fibronectin(Fn),and the histone acetylation marker acetylated histones(Ac-his-tones)in A549 cells were observed.Results Com-pared to the control group,rats with PQ-induced pul-monary fibrosis exhibited a significant decrease in the rate of body weight growth,an increase in lung tissue index(P＜0.05),and a notable increase in the expression and distribution of the fibrosis marker alpha-smooth muscle actin(α-SMA)in lung tissue.The structure of the lung tissue was disrupted,accompanied by the deposition of interstitial collagen fibers.Both N-Tad and Cialis treatments could significantly enhance the rate of weight gain,decrease the lung tissue index,inhibit the expression of α-SMA,and reduce the depo-sition of interstitial collagen in the lung tissue of rats with pulmonary fibrosis.Notably,low-dose N-Tad treatment was comparable to high-dose Cialis treat-ment.At the cellular level,Tadalafil significantly in-hibited the high expression of Fn induced by transfor-ming growth factor beta 1(TGF-β1)in A549 cells.It also upregulated the expression of E-cadherin and sig-nificantly increased the levels of acetylated histones(P＜0.05).Conclusions N-Tad promotes histone acetylation in alveolar epithelial cells,significantly in-hibits epithelial-mesenchymal transition,increases E-cadherin expression,and improves lung tissue structur-al damage and collagen deposition caused by PQ.Ad-ditionally,it offers the advantage of a lower effective dose compared to Cialis,providing a new option for the treatment of pulmonary fibrosis.

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.

Objective:To explore the effect of the defect area and volume of intra-articular impacted fragments (IAIF) on the contact stress of the ankle joint surface.Methods:A 23-year-old male volunteer, 168 cm in height and 60 kg in weight, with no history of trauma or anatomic abnormality of the ankle, was selected. On the basis of a normal ankle finite-element model, IAIF-defect finite-element models were established. The first group consisted of IAIF-defect models with identical area but different volumes: on the distal tibial articular surface the defect area was 4 mm × 5 mm (20 mm 2), and the heights were 2 mm, 3 mm, 4 mm, 5 mm and 6 mm. The second group consisted of IAIF-defect models with identical defect volume but different areas. The defect volume was 90 mm 3, while the defect areas on the distal tibial articular surface were 2 mm×3 mm, 3 mm×3 mm, 3 mm×5 mm, 3 mm×6 mm, and 5 mm×6 mm, with corresponding heights of 15 mm, 10 mm, 6 mm, 5 mm, and 3 mm. Under a 600 N vertical load the contact stress of the ankle joint was calculated, and the finite-element data were recorded and analyzed. Pearson correlation analysis was used to analyze, separately for the two groups, the correlation between IAIF defect and the maximum contact stress (MCS) of the distal tibial articular surface, and simple linear regression analysis was performed to obtain regression equations. Equivalence zero testing was used to verify the correlations and to compare their differences. Results:For IAIF defects with the same area but different volumes, including 4 mm×5 mm×2 mm, 4 mm×5 mm×3 mm, 4 mm×5 mm×4 mm, 4 mm×5 mm×5 mm, and 4 mm× 5 mm×6 mm, the corresponding maximum contact stress (MCS) on the distal tibial joint surface were 3.846 MPa, 3.839 MPa, 3.835 MPa, 3.833 MPa, and 3.831 MPa, respectively, with an average of 3.837 MPa. The mean ±1% range is from 3.799 MPa to 3.875 MPa. The correlation analysis showed that the IAIF defects with the same area but different volumes were negatively correlated with contact stress ( r=-0.956, P=0.011). The linear regression equation was MCS=-0.0002×VI+3.851, where VI denotes IAIF volume. Equivalence zero testing confirmed that all measured values lay within the predefined ±1 % margin, satisfying the equivalence null hypothesis. For IAIF defects of identical volume (90 mm 3) but varying articular surface areas—2 mm×3 mm, 3 mm×3 mm, 3 mm×5 mm, 3 mm×6 mm and 5 mm×6 mm—the corresponding MCS values were 2.147 MPa, 2.812 MPa, 3.622 MPa, 4.476 MPa and 6.186 MPa, respectively (mean 3.849 MPa; equivalence band 3.811-3.887 MPa at ±1% of the mean). Correlation analysis demonstrated a strong positive relationship between identical-volume varying-area IAIF defects and contact stress ( r=0.996, P<0.001). The linear regression equation was MCS=0.168×AI+1.236, where AI denotes IAIF area. Equivalence zero testing indicated that none of the measured values fell within the predefined ±1% margin, failing to satisfy the equivalence null hypothesis. Conclusion:In posterior ankle fractures, the volume change of IAIF defects has no clinical significance in relation to MCS, showing a small negative correlation. However, the area change of IAIF defects is clinically significant in relation to MCS, demonstrating a larger positive correlation.