ObjectiveTranscranial focused ultrasound (tFUS) has emerged as a promising noninvasive neuromodulation technique capable of modulating neural activity with high spatial specificity. However, whether tFUS stimulation of the primary somatosensory cortex (S1) can reliably evoke conscious tactile perception without external peripheral sensory input remains unclear. Therefore, this study examined the feasibility of inducing hand-related tactile perception through targeted S1 stimulation and further investigated how sonication duration (SD), a key temporal parameter, influences the consistency of this perceptual response. The findings may provide empirical evidence for optimizing tFUS parameters in human somatosensory modulation. MethodsForty-eight healthy adults participated in the study and were assigned to two experiments. Experiment 1 included 24 participants and was designed to preliminarily examine whether S1-targeted tFUS could evoke hand-related tactile sensations. This experiment comprised two sub-experiments, Experiment 1a and Experiment 1b, with 12 participants in each. Specifically, Experiment 1a used a randomized active stimulation protocol targeting the bilateral S1 to assess the initial feasibility of inducing contralateral tactile perception, whereas Experiment 1b employed an alternating hemispheric design incorporating both active and sham stimulation to verify the specificity of the tFUS-induced sensations. Experiment 2 enrolled another 24 participants and used a real-sham dual-probe design to control for spatial tactile cues that might arise from probe-scalp contact. Five SD levels, including 200, 400, 600, 800, and 1 000 ms, were systematically tested to evaluate how stimulation duration influenced the behavioral response. The primary behavioral outcome was the perceptual consistency rate, quantified according to the accuracy of contralateral tactile localization. ResultsIn Experiment 1, 91.7% of participants reported reliable hand-related tactile sensations during active tFUS stimulation, including numbness, tingling, or similar sensory experiences. Contralateral localization accuracy under active stimulation was significantly higher than the0.50 chance level (P<0.05). In contrast, localization performance under sham stimulation did not differ from chance, suggesting that the observed tactile responses were mainly induced by active S1-targeted tFUS stimulation rather than nonspecific stimulation cues. In Experiment 2, perceptual consistency rates significantly exceeded the chance level under the 400 and 1 000 ms SD conditions(P<0.05), whereas no significant effect was observed at 200, 600, or 800 ms. Pairwise comparisons further showed that the 400 and 1 000 ms conditions produced significantly higher perceptual consistency rates than the 200 ms condition (P<0.05). ConclusiontFUS stimulation of S1 can elicit distinct hand-related tactile sensations without peripheral sensory input, demonstrating the feasibility of using targeted cortical ultrasound stimulation to induce conscious somatosensory perception. The reliability of this perceptual effect was modulated by sonication duration, indicating that temporal stimulation parameters play an important role in shaping both the occurrence and consistency of behavioral responses. Among the tested conditions, 400 ms appeared to provide a favorable temporal window for generating stable tactile perception, whereas excessively short stimulation may be insufficient to produce consistent responses. These findings highlight the sensitivity of somatosensory networks to ultrasonic modulation and provide useful parameter guidance for the application of tFUS in noninvasive sensory enhancement and cortical functional mapping.

Tissue repair requires the reconstruction of functional vascular networks to restore oxygen and nutrient delivery, eliminate metabolic waste, and maintain tissue homeostasis. Although biochemical factors such as growth factors and cytokines have been extensively studied in vascular regeneration, increasing evidence indicates that mechanical signals from the extracellular matrix (ECM) are equally important regulators of angiogenesis. Matrix stiffness, as a major biomechanical property of the tissue microenvironment, provides critical information that influences endothelial cell (EC) behavior and vascular remodeling through mechanotransduction. However, the biological effects of matrix stiffness are not universally defined as either pro- or anti-angiogenic, but are highly dependent on tissue context, cellular composition, disease progression, and the dynamic changes occurring during tissue repair. Therefore, understanding how matrix stiffness regulates vascular regeneration is essential for developing more precise strategies for tissue engineering and regenerative medicine. In this review, we summarize recent advances in the regulation of angiogenesis by matrix stiffness during tissue repair from multiple perspectives. First, we discuss the direct effects of matrix stiffness on EC behaviors, including differentiation, morphological remodeling, migration, proliferation, barrier maintenance, and vascular network formation. ECs sense mechanical alterations in the surrounding matrix through various mechanosensitive structures, including integrins, focal adhesion complexes, and mechanosensitive ion channels such as Piezo1 and TRPV proteins. These mechanical signals are subsequently transmitted through intracellular pathways involving FAK, RhoA/ROCK, MAPK, and Hippo-YAP/TAZ signaling, leading to cytoskeletal reorganization and transcriptional regulation. Through these mechanisms, matrix stiffness regulates endothelial functional states and determines the balance between regenerative vascular formation and pathological vascular remodeling. Beyond the direct regulation of ECs, we further highlight the importance of stiffness-mediated intercellular communication within the regenerative microenvironment. Matrix stiffness can regulate the behavior and secretory profiles of vascular-associated cells, including mesenchymal stem cells and macrophages, thereby indirectly affecting endothelial function through paracrine mechanisms. Changes in matrix mechanics influence the secretion of angiogenic factors, inflammatory cytokines, and extracellular vesicles from these cells, creating a mechanical regulation network that coordinates vascular regeneration. This perspective extends the traditional concept of matrix stiffness from a physical support structure to an active regulatory signal that integrates multiple cellular responses during tissue repair. Furthermore, we discuss the tissue-specific effects of matrix stiffness in vascular regeneration across different organs, including the aorta, lung, liver, and heart. Although excessive matrix stiffening is frequently associated with fibrosis and vascular dysfunction, the consequences of mechanical changes vary considerably among tissues. Moderate stiffness alterations may support endothelial activation and vascular stabilization in certain regenerative contexts, whereas persistent pathological stiffening can promote inflammation, endothelial dysfunction, and impaired vascular repair. These findings emphasize that the biological meaning of “soft” and “stiff” microenvironments should be interpreted according to specific tissue and experimental conditions rather than as universal mechanical classifications. Finally, we summarize current challenges and future perspectives in this field. A major limitation is the lack of standardized mechanical characterization among different studies, as stiffness measurements are influenced by material properties, testing methods, and experimental conditions, limiting direct comparison across research systems. Moreover, most existing models fail to fully reproduce the dynamic and viscoelastic properties of native ECM during tissue regeneration. Future studies should combine advanced biomaterials with standardized mechanical analysis, organoid models, and multi-omics approaches to establish more accurate mechanical regulatory maps. Overall, this review proposes that matrix stiffness is not merely a structural feature of tissues, but an active biological signal that regulates vascular regeneration through coordinated mechanotransduction and multicellular interactions. A deeper understanding of stiffness-mediated vascular regulation will provide new theoretical insights and therapeutic opportunities for improving tissue repair outcomes.

BACKGROUND:The regeneration and remodeling of Achilles tendon rupture after surgery are difficulties in clinical treatment.Tissue engineering hydrogels afford the possibility on the healing of postoperative Achilles tendon. OBJECTIVE:To investigate the effect of tannic acid modified interpenetrating network hydrogel on tissue regeneration and remodeling of ruptured Achilles tendon in rats. METHODS:(1)The interpenetrating network hydrogel was prepared under the blue light and the immersion of CaSO4 solution.The micromorphology,mechanical properties,adhesion properties,in vitro drug release properties,and biocompatibility of hydrogels were characterized.(2)Thirty Sprague-Dawley rats were randomly divided into sham operation group,operation group,and hydrogel group,with 10 rats in each group.The animal model of Achilles tendon rupture was established in the latter two groups.In the operation group,the ruptured Achilles tendon was sutured using the modified Kessler method.In the hydrogel group,the ruptured Achilles tendon was repaired by the same method,and the tannic acid modified interpenetrating network hydrogel patch was completely wrapped around the joint of the broken end.Four weeks after the operation,imaging examination,histological evaluation,biomechanical test,and the level test of inflammatory factors were performed. RESULTS AND CONCLUSION:(1)Scanning electron microscope showed that tannic acid modified interpenetrating network hydrogels had porous microstructure with pore size of 3-10 μm,and the hydrogels had good in vitro drug release properties,adhesion strength and tensile strength.CCK-8 assay and live/dead staining showed that the hydrogel had no significant effect on the proliferation activity of rat bone marrow mesenchymal stem cells,and had good biocompatibility.(2)MRI imaging showed that compared with the operation group,the Achilles tendon in the hydrogel group showed uniform low signal,the thickness of the anteroposterior diameter of the Achilles tendon was reduced,and the boundary between the Achilles tendon and the surrounding tissue was more clear,and the performance was more similar to that of the sham operation group.Hematoxylin-eosin staining and Masson staining showed that the tendon fibers in the operation group were arranged in a loose and chaotic manner,with increased cell density and disordered arrangement,accompanied by obvious inflammatory cell infiltration,and intratendinous ossification appeared in some areas.In the hydrogel group,the tendon fibers were arranged in an orderly manner;the cell density was reduced and arranged orderly;the inflammatory cell infiltration was significantly reduced.The tensile strength of Achilles tendon in the operation group was lower than that in the sham operation group(P<0.05).The tensile strength of Achilles tendon in the hydrogel group was higher than that in the operation group(P<0.05).Compared with sham operation group,the mass concentration and mRNA expression of interleukin-1β,interleukin-6,and tumor necrosis factor α in Achilles tendon of rats were increased in the operation group(P<0.05).Compared with the operation group,the level and mRNA expression of three inflammatory factors were decreased in the hydrogel group.(3)It is concluded that tannic acid modified interpenetrating network hydrogel can inhibit the local inflammatory response and promote the tendon remodeling.

Heat stroke is a heat-related illness caused by an imbalance between the body's heat production and heat dissipation,which could lead to multiple organ dysfunction syndrome with a high mortality rate.Rapid and effective reduction of core body temperature is key to successful treatment.This article reviews recent progress in the treatment of heat stroke,including new understandings of organ injury mechanisms,the timing,velocity and goals of cooling treatment,evaluation and selection of traditional cooling techniques(such as cold water immersion),and scientific evaluation of new cooling technologies(such as blood purification technology and intravascular heat exchange cooling technology),aiming to promote understanding and treatment of heat stroke.

Lung cancer has the highest incidence and mortality among malignant tumors in China.Persistent subsolid nodules(SSNs)are closely associated with early-stage lung adenocarcinoma.Artificial intelligence(AI),as an emerging technology,is capable of performing in-depth analysis of large-scale imaging data through autonomous learning and possesses the ability to predict outcomes from new data,demonstrating great potential and application prospects in the assessment of SSNs.AI can not only effectively assist radiologists in diagnosis and treatment,but also improve work efficiency while reducing misdiagnosis and missed diagnosis rates.This review summarizes the recent applications and research progress of AI in the assessment of SSNs,to provide new insights for the diagnosis and treatment of SSNs.

Objective To investigate the factors influencing global longitudinal strain(GLS)measured by cardiac magnetic resonance(CMR)in patients with acute ST-segment elevation myocardial infarction(STEMI).Methods Clinical data of 315 hospitalized patients diagnosed with acute STEMI who underwent percutaneous coronary intervention(PCI)at the First Medical Center of Chinese PLA General Hospital from June 2016 to September 2021 were retrospectively collected.After analyzing CMR images of all patients,GLS and other strain parameters were obtained,and then the patients were divided into two groups according to the median GLS.In order to balance gender and age differences,1:1 propensity score matching was performed,and 206 patients were eventually included:GLS>-11.3%group(indicating severe GLS impairment,n=103)and GLS≤-11.3%group(n=103).Baseline characteristics,laboratory indicators,coronary angiographic parameters,electrocardiogram(ECG)features,and CMR parameters were compared between the two groups.Variables showing significant differences were analyzed for their correlation with GLS.Multivariate logistic regression and multiple stepwise linear regression analyses were performed to identify factors associated with GLS impairment.Results Compared with GLS≤-11.3%group,GLS>-11.3%group had significantly higher peak levels of creatine kinase-MB(CK-MB)and troponin T(TnT)(P<0.001).A higher proportion of patients in GLS>-11.3%group had the left anterior descending artery(LAD)as the culprit vessel,while a lower proportion had the right coronary artery(RCA)as the culprit vessel(P<0.001).Additionally,GLS>-11.3%group had longer QRS duration(P<0.001)and a higher incidence of pathological Q waves(P=0.001).Regarding CMR parameters,GLS>-11.3%group exhibited larger global circumferential strain(GCS),infarct size(IS),and left ventricular end-systolic volume(LVESV),as well as lower global radial strain(GRS)and left ventricular ejection fraction(LVEF)(P<0.001).Multivariate logistic regression indicated that peak TnT(OR=1.092,P=0.001),LAD culprit vessel(OR=3.744,P<0.001),and QRS duration(OR=1.026,P<0.001)were significantly associated with severely impaired GLS.Multiple stepwise linear regression analysis showed that the logarithmic value of peak TnT,LAD as the culprit vessel,and the square root of QRS duration were linearly correlated with GLS values(adjusted R2=0.301,P<0.001),and these independent variables explained 30.1%of the variation in GLS.Conclusion Elevated peak TnT,prolonged QRS duration,and LAD as the culprit vessel are significantly associated with severe GLS impairment in STEMI patients,indicating more severe myocardial infarction and worse left ventricular function.

OBJECTIVE: This study reports the first imported case of Lassa fever (LF) in China. Laboratory detection and molecular epidemiological analysis of the Lassa virus (LASV) from this case offer valuable insights for the prevention and control of LF. METHODS: Samples of cerebrospinal fluid (CSF), blood, urine, saliva, and environmental materials were collected from the patient and their close contacts for LASV nucleotide detection. Whole-genome sequencing was performed on positive samples to analyze the genetic characteristics of the virus. RESULTS: LASV was detected in the patient's CSF, blood, and urine, while all samples from close contacts and the environment tested negative. The virus belongs to the lineage IV strain and shares the highest homology with strains from Sierra Leone. The variability in the glycoprotein complex (GPC) among different strains ranged from 3.9% to 15.1%, higher than previously reported for the seven known lineages. Amino acid mutation analysis revealed multiple mutations within the GPC immunogenic epitopes, increasing strain diversity and potentially impacting immune response. CONCLUSION The case was confirmed through nucleotide detection, with no evidence of secondary transmission or viral spread. The LASV strain identified belongs to lineage IV, with broader GPC variability than previously reported. Mutations in the immune-related sites of GPC may affect immune responses, necessitating heightened vigilance regarding the virus.
Humans ; China/epidemiology* ; Genome, Viral ; Lassa Fever/virology* ; Lassa virus/classification* ; Molecular Epidemiology ; Phylogeny

OBJECTIVE: Data on homocysteine (Hcy) status and its determinants are limited among women during pregnancy and postpartum. This cross-sectional study aimed to investigate Hcy levels during pregnancy and postpartum, and to explore the determinants like geographic factor. METHODS: This study was conducted in women at mid-pregnancy, late-pregnancy and postpartum from southern, central and northern China. Approximately 132 women were included in each stratum by the three phases and regions. Plasma Hcy concentrations were assessed using high-performance liquid chromatography (HPLC), with hyperhomocysteinemia defined as > 10.0 µmol/L. Quantile regression was to estimate medians and interquartile ranges ( IQRs), and logistic regression to examine the determinants of hyperhomocysteinemia. RESULTS: For 1,190 women included, the median (IQR) Hcy concentration was 5.66 (4.62, 7.37) μmol/L. The adjusted median in mid-pregnancy, late-pregnancy and postpartum women was 4.75 (4.13, 5.54), 5.72 (4.81, 6.85) and 7.09 (5.65, 8.75) μmol/L, respectively, showing an increasing trend ( P < 0.001). This increasing trend persisted across the three regions. Higher Hcy concentrations were observed in women residing in northern region and those with younger age or lower economic status. A total of 106 (8.9%) women had hyperhomocysteinemia, with a higher prevalence in those residing in northern region (16.0%), or in postpartum women (16.5%). CONCLUSION Hcy levels, varying with geographic region, maternal age and economic status, are increased from mid-pregnancy to late-pregnancy and postpartum, indicating a need to monitor Hcy levels in pregnant and postpartum women to control potential risks related to elevated Hcy levels.
Humans ; Female ; Pregnancy ; Homocysteine/blood* ; China/epidemiology* ; Adult ; Postpartum Period/blood* ; Cross-Sectional Studies ; Hyperhomocysteinemia/blood* ; Young Adult ; Pregnancy Trimester, Third/blood* ; Pregnancy Trimester, Second ; East Asian People

Langerhans cell histiocytosis of bone is a rare tumor disease characterized by the large accumulation of CD1a⁺ and CD207⁺ dendritic cells in tissues of unknown cause.It mainly occurs in children aged 1-4 years old,with incidences of 4-6 per million in children and 1-2 per million in adults.Due to its low incidence,diverse clinical manifestations,and no obvious specificity of imaging manifestations,the definitive diagnosis and early treatment of this type of tumor are challenging.In this paper,we report 8 cases of Langerhans cell histiocytosis of bone and review the relevant literature published in the past five years to summarize the clinical characteristics,pathological features,diagnosis,treatment,and prognosis of this disease.
Humans ; Bone Diseases/therapy* ; Histiocytosis, Langerhans-Cell/therapy*