To investigate the molecular mechanisms underlying the mechanosensitive ion channel PI-EZO2 in osteoarthritis(OA),we developed a lentiviral vector for endogenous PIEZO2 overexpression and established a stable PIEZO2-high-expressing immortalized human primary chondrocyte line.By map-ping the open reading frame of the PIEZO2 locus and designing sequence-specific sgRNA,we employed the CRISPR/Cas9 synergistic activation mediator(SAM)system to precisely integrate transcriptional ac-tivation elements into the PIEZO2 promoter region.Lentiviral-mediated targeted genomic integration en-sured endogenous PIEZO2 overexpression,confirmed by mCherry fluorescence tracing coupled with flow cytometric sorting,which revealed membrane-specific localization of PIEZO2 protein(localization effi-ciency:78.49％).Quantitative PCR demonstrated a 17-fold upregulation of PIEZO2 mRNA,while Western blotting validated enhanced membrane-localized protein expression.Strikingly,PIEZO2-overex-pressing chondrocytes exhibited hallmark OA metabolic phenotypes compared to wild-type controls:typeⅡ collagen mRNA expression decreased to 50％of baseline levels,whereas matrix metalloproteinase 13(MMP13)mRNA surged by 20-fold.These alterations recapitulated the pathological matrix metabolic phenotype observed in biomechanical OA models induced by cyclic mechanical stress(10％strain,0.5 Hz,8 h/day for 2 consecutive days).Collectively,we successfully generated a human chondrocyte model with stable PIEZO2 overexpression,which faithfully mirrors mechanotransduction-driven OA progression.This engineered cellular system provides a robust platform for dissecting PIEZO2-mediated mechanosig-naling networks and advancing targeted therapeutic discovery.

Time-of-flight secondary ion mass spectrometer(TOF-SIMS)is a highly sensitive surface analysis instrument with high spatial resolution.Traditional TOF-SIMS instruments for sample targets use high field extraction methods.Although the ion collection efficiency is high,it is prone to issues such as low-energy ion beam defocusing,sample morphology sensitivity,and organic molecule ion dissociation.This study aimed to develope an efficient low-field ion extraction system suitable for TOF-SIMS with a continuous beam source.The SIMION simulation software was used to construct a model of the secondary ion optical extraction system.The key factors affecting the extraction efficiency were studied,and the structural parameters of the extraction cone were optimized.Using an indium target as the sample,an experimental test of the performance of the ion extraction system was carried out on the TOF-SIMS instrument.The influences of the voltages of the ion extraction cone and the single lens on the ion extraction efficiency were consistent with the simulation results.By adopting the technology of deflection and coaxial dynamic compensation,the imaging field of view of the ion extraction system was increased to 500 μm×500 μm.The energy window of the ion extraction system reached 10 eV,and the large imaging depth of field of 400 μm was achieved.In the test of a 5 mg/L cholesterol thin film sample,the signal-to-noise ratio of the characteristic peak[M-OH]+reached 4453.The results showed that this low-field secondary ion extraction system effectively improved the performance of the continuous beam TOF-SIMS instrument.

The patient is a 63-year-old man with a history of chronic illness, presenting with intermittent low-grade fever, recurrent dry cough, and shortness of breath upon exertion. Lung CT showed a nodule in the left lung and a large mass in the right lung with liquefactive necrosis and an air-fluid level accompanied by pleural effusion. Laboratory findings showed significantly increasedf immunoglobulin G (IgG), IgG4, and total immunoglobulin E, along with a mild increase in eosinophils, and moderate elevations in erythrocyte sedimentation rate and high-sensitivity C-reactive protein. Malignant tumors, immunological, and hematological diseases were ruled out. Various antibiotic treatments were ineffective and the condition was recurrent. Conventional methods failed to identify the pathogen. Metagenomic next-generation sequencing (mNGS) technology was used to detect Mycobacterium monacense from lung tissue. Targeted antibiotic treatment was effective with no further episodes of low-grade fever and alleviation of dry cough symptoms. This case underscores the clinical significance of mNGS technology for the diagnosis and treatment of unexplained pulmonary infections, providing a useful reference for clinical diagnostic and treatment.

Objectives:To evaluate the incidence of neurological complications following left ventricular assist device(LVAD)implantation and to investigate related risk factors.Methods:A retrospective analysis was conducted on 151 patients who underwent LVAD implantation at Fuwai Hospital between June 2017 and September 2024.Clinical characteristics and postoperative survival outcomes were compared between patients with and without neurological complications.Results:Neurological complications occurred in 21 patients(13.9%)postoperatively,15 cases were ischemic strokes,5 cases were symptomatic intracranial hemorrhages or subarachnoid hemorrhages,and 1 case was transient ischemic attack(TIA).The total incidence of neurological complications was 0.08 events per person-year(EPPY),ischemic stroke was 0.06 EPPY and hemorrhagic stroke was 0.02 EPPY.Compared with patients without neurological complications,patients with neurological complications had a higher proportion of preoperative aortic regurgitation and tricuspid regurgitation,lower triglyceride levels,a lower rate of concurrent left atrial appendage resection and a higher rate of concurrent aortic valve replacement surgery.Multivariate cox regression analysis revealed that higher preoperative triglyceride levels(HR=0.21,95%CI:0.08-0.56,P=0.002)were associated with neurological complications.The median follow-up time was 508.0(186.5,931.5)days,12 out of 15 cases of ischemic stroke experienced no long-term sequelae,while 3 patients had varying degrees of residual deficits.All 5 patients with hemorrhagic stroke died,with 2 deaths directly attributed to hemorrhage.Kaplan-Meier survival curve analysis indicated that patients with neurological complications had a significantly lower survival rate(log-rank P=0.005).Conclusions:Neurological complications after LVAD implantation are predominantly ischemic strokes.Although less frequent,hemorrhagic strokes are associated with worse outcomes.Higher preoperative triglyceride levels is associated with neurological complications.

To investigate the molecular mechanisms underlying the mechanosensitive ion channel PI-EZO2 in osteoarthritis(OA),we developed a lentiviral vector for endogenous PIEZO2 overexpression and established a stable PIEZO2-high-expressing immortalized human primary chondrocyte line.By map-ping the open reading frame of the PIEZO2 locus and designing sequence-specific sgRNA,we employed the CRISPR/Cas9 synergistic activation mediator(SAM)system to precisely integrate transcriptional ac-tivation elements into the PIEZO2 promoter region.Lentiviral-mediated targeted genomic integration en-sured endogenous PIEZO2 overexpression,confirmed by mCherry fluorescence tracing coupled with flow cytometric sorting,which revealed membrane-specific localization of PIEZO2 protein(localization effi-ciency:78.49％).Quantitative PCR demonstrated a 17-fold upregulation of PIEZO2 mRNA,while Western blotting validated enhanced membrane-localized protein expression.Strikingly,PIEZO2-overex-pressing chondrocytes exhibited hallmark OA metabolic phenotypes compared to wild-type controls:typeⅡ collagen mRNA expression decreased to 50％of baseline levels,whereas matrix metalloproteinase 13(MMP13)mRNA surged by 20-fold.These alterations recapitulated the pathological matrix metabolic phenotype observed in biomechanical OA models induced by cyclic mechanical stress(10％strain,0.5 Hz,8 h/day for 2 consecutive days).Collectively,we successfully generated a human chondrocyte model with stable PIEZO2 overexpression,which faithfully mirrors mechanotransduction-driven OA progression.This engineered cellular system provides a robust platform for dissecting PIEZO2-mediated mechanosig-naling networks and advancing targeted therapeutic discovery.

Objectives:To evaluate the incidence of neurological complications following left ventricular assist device(LVAD)implantation and to investigate related risk factors.Methods:A retrospective analysis was conducted on 151 patients who underwent LVAD implantation at Fuwai Hospital between June 2017 and September 2024.Clinical characteristics and postoperative survival outcomes were compared between patients with and without neurological complications.Results:Neurological complications occurred in 21 patients(13.9%)postoperatively,15 cases were ischemic strokes,5 cases were symptomatic intracranial hemorrhages or subarachnoid hemorrhages,and 1 case was transient ischemic attack(TIA).The total incidence of neurological complications was 0.08 events per person-year(EPPY),ischemic stroke was 0.06 EPPY and hemorrhagic stroke was 0.02 EPPY.Compared with patients without neurological complications,patients with neurological complications had a higher proportion of preoperative aortic regurgitation and tricuspid regurgitation,lower triglyceride levels,a lower rate of concurrent left atrial appendage resection and a higher rate of concurrent aortic valve replacement surgery.Multivariate cox regression analysis revealed that higher preoperative triglyceride levels(HR=0.21,95%CI:0.08-0.56,P=0.002)were associated with neurological complications.The median follow-up time was 508.0(186.5,931.5)days,12 out of 15 cases of ischemic stroke experienced no long-term sequelae,while 3 patients had varying degrees of residual deficits.All 5 patients with hemorrhagic stroke died,with 2 deaths directly attributed to hemorrhage.Kaplan-Meier survival curve analysis indicated that patients with neurological complications had a significantly lower survival rate(log-rank P=0.005).Conclusions:Neurological complications after LVAD implantation are predominantly ischemic strokes.Although less frequent,hemorrhagic strokes are associated with worse outcomes.Higher preoperative triglyceride levels is associated with neurological complications.

The patient is a 63-year-old man with a history of chronic illness, presenting with intermittent low-grade fever, recurrent dry cough, and shortness of breath upon exertion. Lung CT showed a nodule in the left lung and a large mass in the right lung with liquefactive necrosis and an air-fluid level accompanied by pleural effusion. Laboratory findings showed significantly increasedf immunoglobulin G (IgG), IgG4, and total immunoglobulin E, along with a mild increase in eosinophils, and moderate elevations in erythrocyte sedimentation rate and high-sensitivity C-reactive protein. Malignant tumors, immunological, and hematological diseases were ruled out. Various antibiotic treatments were ineffective and the condition was recurrent. Conventional methods failed to identify the pathogen. Metagenomic next-generation sequencing (mNGS) technology was used to detect Mycobacterium monacense from lung tissue. Targeted antibiotic treatment was effective with no further episodes of low-grade fever and alleviation of dry cough symptoms. This case underscores the clinical significance of mNGS technology for the diagnosis and treatment of unexplained pulmonary infections, providing a useful reference for clinical diagnostic and treatment.

Further evidence is needed to explore the impact of high-altitude environments on the neurologic function of neonates.Non-invasive techniques such as cerebral near-infrared spectroscopy and amplitude-integrated electroencephalography can provide data on cerebral oxygenation and brain electrical activity.This study will conduct multiple cerebral near-infrared spectroscopy and amplitude-integrated electroencephalography monitoring sessions at various time points within the first 3 days postpartum for healthy full-term neonates at different altitudes.The obtained data on cerebral oxygenation and brain electrical activity will be compared between different altitudes,and corresponding reference ranges will be established.The study involves 6 participating centers in the Chinese High Altitude Neonatal Medicine Alliance,with altitude gradients divided into 4 categories:800 m,1 900 m,2 400 m,and 3 500 m,with an anticipated sample size of 170 neonates per altitude gradient.This multicenter prospective cohort study aims to provide evidence supporting the impact of high-altitude environments on early brain function and metabolism in neonates.[Chinese Journal of Contemporary Pediatrics,2024,26(4):403-409]

Fluorescent carbon dots(CDs)were synthesized via a solvothermal method with citric acid and urea as raw materials,and ethylene glycol as reaction solvent.The micromorphology,crystal structure,elemental composition,surface functional group,and optical property of as-synthesized CDs were characterized.The excitation-dependent fluorescence property of CDs was investigated,and the effects of synthesis conditions including reaction temperature,reaction time and raw materials on excitation and emission wavelengths of the CDs were also discussed.Then,a series of CDs-based fluorescent composites were prepared by combining CDs with starch,nano-silica,montmorillonite,kaoline,kieselguhr and magnesium oxide,respectively.Finally,the CDs-starch composites were used for latent fingerprint development on smooth substrates,and the qualitative as well as quantitative evaluation of the contrast,sensitivity and selectivity in fingerprint development were also made.Enhanced development of latent fingerprints was thus achieved by the aid of the excitation-dependent fluorescence property of CDs-starch composite combined with the optical filtering technique,which could decrease the background noise interference to a great extent.Experimental results showed that,the contrast between fingerprint(developing signal)and substrate(background noise)was obvious,exhibiting a strong contrast;the minutiae of papillary ridges were clear,indicating a high sensitivity;the adsorption between CDs-starch composites and fingerprint residues was specific,showing a good selectivity.

Objective: To investigate the risk factors for human cytomegalovirus infection after allogeneic hematopoietic stem cell transplantation in children and the impact of human cytomegalovirus infection on post-transplant immune reconstitution. Methods: A Retrospective Co-Hort study design was used to include 81 children treated with allo-HSCT from January 2020 to March 2022 at the Department of Hematology, Capital Institute of Pediatrics, Beijing, China, and followed up for 1 year. Real-time quantitative PCR was used to detect positive detection of HCMV in children after allo-HSCT, multifactorial logistic regression modeling was used to analyze the risk factors leading to HCMV infection, and generalized estimating equation modeling was used to analyze the effect of HCMV infection on the T-cells of the children who received allo-HSCT. Results: The age M(Q₁, Q₃) of 81 children was 5.1 years (10 months, 13.8 years), and 50 (61.7%) were male. By the endpoint of follow-up, a total of 50 HCMV-positive cases were detected, with an HCMV detection rate of 61.7%; The results of multifactorial logistic regression modeling showed that children with grade 2-4 aGVHD had a higher risk of HCMV infection compared with grade 0-1 after transplantation [OR (95%CI) value: 2.735 (1.027-7.286)]. The results of generalized estimating equation modeling analysis showed that the number of CD3⁺T cells in HCMV-positive children after transplantation was higher than that in the HCMV-negative group [RR (95%CI) value: 1.34 (1.008-1.795)]; the ratio of CD4⁺T/CD8⁺T cells was smaller than that in the HCMV-negative group [RR (95%CI) value: 0.377 (0.202-0.704)]; the number of CD8⁺T cells was higher than that in the HCMV-negative group [RR (95%CI) value: 1.435 (1.025-2.061)]; the number of effector memory CD8⁺T cells was higher than that in the HCMV-negative group [RR (95%CI) value: 1.877 (1.089-3.236)]. Conclusion: Acute graft-versus-host disease may be a risk factor for HCMV infection in children after allo-HSCT; post-transplant HCMV infection promotes proliferation of memory CD8+T-cell populations and affects immune cell reconstitution.
Male ; Humans ; Child ; Female ; Immune Reconstitution ; Retrospective Studies ; Cytomegalovirus Infections ; Hematopoietic Stem Cell Transplantation/adverse effects* ; CD8-Positive T-Lymphocytes