Xiaobing Li

Pb(Mg_1/3Nb_2/3)O_3-xPbTiO₃ (PMN-PT) single crystals, characterized by an ultrahigh piezoelectric response, are well suited for transducers used in medical ultrasound imaging. A high-frequency ultrasound transducer with a center frequency above 45 MHz was designed and fabricated based on a high-performance PMN-0.30PT single crystal. A bandwidth of 58.3% @−6dB was measured at ultra-high frequency after the size effect had been overcome in the micro-transducer. An axial resolution of 36 μm was achieved in B-mode imaging of a tungsten-wire phantom, and animal-skin imaging further confirmed the transducer capability. These results indicate that the PMN-0.30PT single crystal is a promising material for high-frequency medical ultrasound imaging applications.

Introduction: Super-enhancers play crucial roles in tumor development as key transcriptional regulatory elements, yet their prognostic value in bladder cancer (BLCA) remains to be systematically elucidated. Objective: This study aimed to comprehensively analyze the regulatory mechanisms of super-enhancer-related genes (SERGs) in predicting BLCA prognosis and immune therapy response. Methods: This study integrated BLCA RNA sequencing data from the cancer genome atlas (training set) and gene expression omnibus (validation set) databases and obtained SERG sets from the SEdb database. Using 101 machine learning ensemble frameworks, we screened and validated SERG sets with significant prognostic value and constructed a risk score model was constructed based on based on CoxBoost and plsRcox. Model performance was evaluated through nomograms. We conducted an in-depth analysis of the association between the risk model and tumor immune microenvironment, identified key hub genes through differential expression analysis, survival analysis, and receiver operating characteristic curve analysis, and performed multi-dimensional validation using immunohistochemistry and single-cell sequencing data. Results: Through machine learning algorithm optimization, we identified eight core genes (AHNAK, NT5DC3, NFIC, MTHFD1L, C1QTNF6, SLC45A3, QRICH2, KRT8). High-risk group patients exhibited poor prognosis and elevated immune and tumor immune dysfunction and exclusion scores, suggesting potential immune therapy resistance. The single-sample gene set enrichment analysis analysis revealed significant positive correlations between risk scores and multiple key signaling pathways, including extracellular matrix-receptor interaction, regulation of actin cytoskeleton, and pathogenic Escherichia coli infection, focal adhesion, melanoma, and gap junction pathways. Further analysis indicated that C1QTNF6 and MTHFD1L displayed significant potential as biomarkers based on expression profiles across cell types. Conclusion: This study pioneered the construction of a prognostic prediction model for BLCA based on SERGs, revealing the crucial role of super-enhancers in regulating the tumor immune microenvironment and identifying potential therapeutic targets and prognostic markers. This research provides a new molecular typing strategy for the precision treatment of BLCA while establishing a theoretical foundation for personalized immunotherapy.

Exosomes, released from diverse cells as nanoscale lipid bilayer vesicles, mediate intercellular communication and participate in various physiological and pathological processes. Thereinto, tumor-derived exosomes (T-EXOs) with molecular cargoes of parent tumor cells act as attractive biomarkers for tumor liquid biopsy. The amount of T-EXOs and their levels of contained specific proteins and nucleic acids are closely associated with cancer burden and classification. Nevertheless, the nanoscale size and relatively low abundance of exosomes, as well as complex body liquid matrix pose daunting challenges for efficient isolation and sensitive detection of T-EXOs. Biosensing as fast, convenient and accurate method, has been widely employed for the detection of biomarkers over the past decades. Among them, electrochemical sensors can sensitively detect biomarkers by measuring of the change of electrical signal caused by oxidation or reduction at the working electrode surface. This review aims to summarize the recent advance in electrochemical biosensors for quantification, and protein and RNA analysis of exosomes. Further, challenges and future perspectives for exosome-based liquid biopsy have been discussed.

High‐quality ternary relaxor ferroelectric (100)‐oriented Mn‐doped 0.36Pb(In _1/2 Nb _1/2 )O ₃ ‐0.36Pb(Mg _1/3 Nb _2/3 )O ₃ ‐0.28PbTiO ₃ (Mn‐PIMNT) thin films were grown on SrRuO ₃ ‐buffered SrTiO ₃ single‐crystal substrate in a wide deposition temperature range of 550‐620°C using the pulsed laser deposition method. The phase structure, ferroelectric, dielectric, piezoelectric properties, and nanoscale domain evolution were studied. Under the deposition temperature of 620°C, the ferroelectric hysteresis loops and current‐voltage curves showed that the film owned significantly enhanced remnant ferroelectric polarization of 34.5 μC/cm ² and low leakage current density of 2.7 × 10 ⁻¹⁰ A/cm ² . Moreover fingerprint‐type nanosized domain patterns with polydomain structures and well‐defined macroscopic piezoelectric properties with a high normalized strain constant of 40 pm/V was obtained. Under in situ DC electric field, the domain evolution was investigated and 180° domain reversal was observed through piezoelectric force microscope. These global electrical properties make the current Mn‐PIMNT thin films very promising in piezoelectric MEMS applications.