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.

This article reports a diagnostically and therapeutically challenging case of small intestinal marginal zone lymphoma. The patient presented with recurrent abdominal pain as the chief complaint, and imaging revealed multifocal small bowel wall thickening with high uptake, multisegmental luminal stenosis, and proximal dilation. Initial diagnostic workup, including gastroscopy, colonoscopy, and enteroscopy with biopsy, failed to establish a definitive diagnosis. Empirical anti-tuberculosis therapy was ineffective. A repeat enteroscopic biopsy performed over eight months after symptom onset eventually confirmed the diagnosis of mucosa-associated lymphoid tissue (MALT) extranodal marginal zone lymphoma. Despite three different chemotherapy regimens, the patient's intestinal obstruction symptoms persisted, with imaging still showing multifocal bowel wall thickening and hypermetabolic activity. A critical diagnostic dilemma arose regarding whether the PET/CT-positive lesions represented residual lymphoma or fibrotic scarring, whether further chemotherapy adjustments were warranted, and whether surgical resection was necessary. Multidisciplinary discussion concluded that imaging had limited discriminatory value in this scenario and that surgical intervention should be pursued if feasible. The patient successfully underwent partial small bowel resection, with postoperative pathology confirming no residual lymphoma but significant fibrotic changes. The patient has since resumed a normal diet, with body weight nearly restored to pre-illness levels. This case highlights that fibrotic transformation is a common sequela of treated marginal zone lymphoma and that PET/CT may misleadingly suggest residual disease, potentially leading to unnecessary chemotherapy. Timely surgical intervention is crucial in such scenarios.

Objective To design a centrifugal agtomization principle-based disinfection and disinsection device for plateau areas.Methods A disinfection and disinsection device was developed based on centrifugal atomization principle,which was composed of a spraying body,lifting and rotating mechanisms,an electrical control system,a spray tank and a sprayer carriage.The spraying body consisted of spraying components,a motor,an air blower,a fan and etc,and the spraying components adopted the structural form of multi-layer disc stacking to realize the atomization of liquid medicine;the lifting mechanism implemented up-and-down adjustment of the air blower through an electric actuartor,and the rotating mechanism executed left-and-right adjustment of the air blower thrgouth the worm gear motor and limit switch;the electrical control system was made up of a power source,electrical devices,a distribution system and a control system,in which a lead-acid battery pack was used for power supply and a DGUS touch screen and a DCS001 controller were involved in the control system;the spray tank was formed of a tank body,a needle valve,a water pump,float switch,etc;the sprayer carriage comprised a frame,a pusher,two sealing plates and four wheels.Some disc samples with different diameters were trial produced,and comparison experiments were carried out to investigate the relationship between disc diameter,motor speed,spray flow rate and atomization effect;a prototype was manufactured for performance testing of the device.Results The disc diameter and motor speed were inversely proportional to the droplet size;the spray flow rate was directly proportional to the droplet size,when the spray flow rate increased by 60%,the increment of the droplet size was restrained within 2%to 11%.The prototype test results indicated that the device could be used for ultra-low-volume disinfection and insecticide in plateau areas,with the D50 and D90 of the droplet size being 31 and 48 μm,respectively.Conclusion The device developed gains advantages in atomiztion,and meets the requirements for epidemic prevention,disinfection and disinsection in plateau areas.[Chinese Medical Equipment Journal,2025,46(4):35-39]

BACKGROUND:During the treatment of posterolateral tibial plateau fractures through the fibular head approach,the gap between the fibular head and the lateral plateau cannot accommodate the posterior placement of a plate for all patients.OBJECTIVE:To analyze,via finite element analysis,the differences in fixation strength resulting from varying the angles and quantities of horizontal arm variable angle screws in the plate during the treatment of posterolateral tibial plateau fractures through the fibular head approach.METHODS:A finite element model was established based on CT images of the knee to ankle joints of a 30-year-old healthy adult male volunteer.The models were divided into two categories:posteriorly placed group and non-posteriorly placed group based on whether the lateral locking compression plate was posteriorly placed.The posteriorly placed group was further subdivided into groups A-D based on the offset angle of the two variable angle screws(0°,5°,10°,and 15°).The non-posteriorly placed group was subdivided into groups E and F based on offset angles(0° and 15°).Finite element analysis was used to evaluate the von Mises stress distribution,maximum von Mises stress,and compressive displacement under loads of 250,500,and 750 N,exploring the mechanical differences between the groups.RESULTS AND CONCLUSION:(1)Finite element analysis results showed that under a 750 N load,the maximum compressive displacement trend of the internal fixation device was D＜B=C=F＜A＜E.The trend for maximum von Mises stress was B＜C＜A＜D＜F＜E.The trend for maximum compressive displacement on the bone was C=D＜B＜A＜F＜E,and for maximum von Mises stress,it was B＜C＜A＜F＜D＜E.The displacement and stress trends for the six models were similar under loads ranging from 250 N to 750 N.(2)These results suggest that for posterolateral tibial plateau fractures fixed through the fibular head approach,posterior placement of the plate should aim to accommodate two screws.If only one screw can be fixed during surgery,variable angle screws should be offset in the range of 0-15° to increase the probability of securing two screws.

Aim To evaluate the role of the glucose transporter protein 1(GLUT1)-dependent glycolytic in the attenuation of oxygen-glucose deprivation-reoxygen-ation(OGD/R)injury in HK-2 cells by dexmedetomi-dine(Dex).Methods C57/BL6 mice were random-ly divided into three groups(n=6),namely,sham operation group(Sham group),renal ischemia reper-fusion group(I/R group)and Dex group(I/R+Dex group).Serum creatinine(Cr)and urea nitrogen(BUN)were measured,while the levels of key glyco-lytic enzymes HK2,PFKFB3 and GLUT1 were meas-ured.HK-2 cells were cultured and randomised into seven groups(n=6),which was treated with OGD/R,overexpression or interference with GLUT1,Dex and glycolysis inhibitor 2-DG.CCK-8 and LDH activi-ty were used to detect cellular damage.Glycolysis lev-els were detected by lactate and ECAR.The inflamma-tory level was reflected by qRT-PCR for IL-6 and TNF-α.qRT-PCR and Western blot were performed to de-tect the levels of GLUT1,HK2,and PFKFB3.Results Dex significantly ameliorated kidney injury and HK-2 cell injury(P＜0.05).Dex inhibited the OGD/R-induced rise in lactate and extracellular acidification rate(ECAR),as evidenced by suppression of the ex-pression of GLUT1,HK2 and PFKFB3(P＜0.05).In vitro experiments showed that GLUT1 knockdown sig-nificantly improved OGD/R-induced cellular damage.Lactate,ECAR,glycolysis-related mRNAs and pro-teins were inhibited by GLUT1 knockdown(P＜0.05).Significantly,there were no significant differ-ences in above indexes after Dex treatment based on GLUT1 knockdown.Overexpression of GLUT1 abroga-ted the protective effects of Dex,while reversing the inhibitory effects of Dex on the expression of GLUT1,HK2,and PFKFB3(P＜0.05).Conclusions Dexmedetomidine attenuates OGD/R induced injury in HK-2 cells by inhibiting GLUT1-dependent glycolysis.

Idiopathic pulmonary fibrosis(IPF)and lung cancer(LC)pose a serious threat to human health,the prognosis of IPF is poor,the 5-year survival rate is low,and the incidence rate and mortality of LC are high.At present,IPF combined with LC(IPF-LC)has attracted much attention,but the pathogenesis is unclear.Epidemiology shows that,the risk of LC in IPF patients is 7 times than that of the general population,the incidence rate varies in different regions,which is related to smoking rate and diagnostic criteria.In terms of pathogenesis,chronic inflammation,angiogenesis,signaling pathways,aging,gene mutations,epithelial mesenchymal transition(EMT),and immune dysfunction are common pathogenic factors of both,and pathological changes such as smoking and pulmonary fibrosis increase the risk of LC.Thoroughly studying these mechanisms is of great significance for the early diagnosis,treatment strategy formulation,and improvement of patient prognosis of IPF-LC.

Objective:To observe the intervention effect of personalized nutrition program combined with rehabilitation training in stroke rehabilitation patients.Methods:86 stroke rehabilitation patients who were admitted to our hospital from January 2023 to June 2024 were prospectively selected,they were divided into control group and study group according to the random number table method,with 43 cases in each group,the control group received rehabilitation training,while the study group received personalized nutrition program combine with rehabilitation training.Simple Fugl Meyer motor function(FMA)score,immune function indicators[immunoglobulin(Ig)A,IgG,complement C3,IgM,complement C4],National Institutes of Health Stroke Scale(NIHSS),nutritional status indicators[albumin(ALB),prealbumin(PA),total protein(TP),hemoglobin(HB)],Stroke Specific Quality of Life Scale(SS-QOL),Barthel Index(BI)score were compared between the two groups.Results:NIHSS score in the study group at 8 weeks after intervention was lower than that in the control group,and SS-QOL score,BI score,FMA score,IgM,IgA,IgG,complement C3,complement C4,ALB,HB,TP and PA were higher than those in the control group(P＜0.05).Conclusion:Personalized nutrition program combined with rehabilitation training in stroke rehabilitation patients,can reduce neurological damage,improve limb motor function,enhance nutritional status,immunity,and quality of life.

This study was aimed at determining the molecular characteristics of Yersinia pestis in the natural plague foci around Qinghai Lake through single nucleotide polymorphism technology,to lay a foundation for molecular epidemiological and source-tracing analysis of Y.pestis in this area.Using the whole genome sequencing technology,we obtained the whole genome sequences of 84 representative Y.pestis strains.Using the sequences of Y.pestis and Yersinia pseudotuberculosis IP32953 from the NCBI database as references,we compared and analyzed the 2 298 SNP loci of these strains.From 1957 to 2020,84 representative strains of Y.pestis from the natural plague foci around Qinghai Lake were divided into two clades:1.IN2 and 3.ANT1.The 1.IN2 clade was the characteristic population of Y.pestis throughout all epidemic years in this area.Additionally,analysis of the SNP distribution and hosts in the region indicated that the 1.IN2 clade was located in five counties except Wulan,whereas the 3.ANT1 clade was isolated from Himalayan marmot and dog in two counties.In conclusion,the population structure of SNP of Y.pestis in the natural plague foci around Qinghai Lake is relatively simple,and SNP analysis of Y.pestis provided a scientific basis for tracing plague epidemic sources and formulating plague prevention and control measures in this area.

Idiopathic pulmonary fibrosis(IPF)and lung cancer(LC)pose a serious threat to human health,the prognosis of IPF is poor,the 5-year survival rate is low,and the incidence rate and mortality of LC are high.At present,IPF combined with LC(IPF-LC)has attracted much attention,but the pathogenesis is unclear.Epidemiology shows that,the risk of LC in IPF patients is 7 times than that of the general population,the incidence rate varies in different regions,which is related to smoking rate and diagnostic criteria.In terms of pathogenesis,chronic inflammation,angiogenesis,signaling pathways,aging,gene mutations,epithelial mesenchymal transition(EMT),and immune dysfunction are common pathogenic factors of both,and pathological changes such as smoking and pulmonary fibrosis increase the risk of LC.Thoroughly studying these mechanisms is of great significance for the early diagnosis,treatment strategy formulation,and improvement of patient prognosis of IPF-LC.

Objective:To establish a stable rat model of sequelae of pelvic inflammatory disease(SPID)with clinical characteristics,and to provide a reliable experimental model for the study of the pharmcological effect and mechanism of SPID.Methods:Twenty-four 7-week-old SD rats were divided into sham operation group,model-A(108 cfu/mL mixed bacterial solution,0.2 mL),model-B(109 cfu/mL mixed bacterial solution 0.2 mL),and model-C(108 cfu/mL E.coli 0.2 mL).The weight of the rat's uterine was weighed and the uterine index was calculated.The automatic hematology analyzer was used to detect the blood routine;hematoxylin-eosin staining(HE)and masson staining were used to detect uterine pathlogical changes in rats.Enzyme-linked immunosorbent assay(ELISA)was used to detect interleukin-1β(IL-1β),interleukin-6(IL-6)and tumor necrosis factor-α(TNF-α)in rat uterine tissue homogenates.Western blot was used to detect the expression of proteins related to NF-κB signaling pathway.Results:Compared with the sham operation group,the uterine index of model-A,model-B,and model-C were significantly increased(P＜0.05,P＜0.01).The levels of WBC and NE in the model-A increased significantly(P＜0.01).The level of LY in model-B decreased significantly(P＜0.01).The levels of IL-1β,TNF-α in model-A,model-B,and model-C were significantly increased(P＜0.01).The levels of IL-6 in model-A and model-B were significantly increased(P＜0.05,P＜0.01).The collagen volume fraction of model-A and model-B were significantly increased(P＜0.01).Mechanism study indicates that the expression levels of p-IKKβ/IKKβ,p-IκBα/IκBα and p-p65/p65 in model-A were significantly increased(P＜0.01),and the expression levels of IκBα/β-actin were significantly decreased(P＜0.01).The expression level of p-IKKβ/IKKβ in model-B was significantly increased(P＜0.01).Conclusions:A stable rat model of SPID that conforms to clinical characteristics can be successfully constructed by combining 0.2 mL of mixed bacterial solution with a concentration of 108 cfu/mL and mechanical injury.This modeling method intervened in the expression of the NF-κB inflammatory signaling pathway.