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Xiangqian Qi

Publications and source records attributed to Xiangqian Qi.

3 recordsLinked to original sources

Radiomics-based gradient boosting model on contrast-enhanced MRI for non-invasive prediction of epidermal growth factor receptor expression and therapeutic response to EGFR-targeted antibody-drug conjugates in high-grade glioma organoid models.

BACKGROUND: Epidermal growth factor (EGF) and its receptor EGF(EGFR) play crucial roles in glioblastoma (GBM) prognosis. However, non-invasive assessment of their expression remains challenging. This study aimed to determine whether radiomics features extracted from contrast-enhanced MRI could predict EGFR expression in high-grade gliomas (HGG) and to explore their associations with immune infiltration and therapeutic response of EGFR-Targeted antibody drug conjugates(EGFR-ADCs). METHODS: We extracted radiomic features from contrast-enhanced MRI of 298 GBM patients from The Cancer Imaging Archive (TCIA) and matched them with RNA-seq data from The Cancer Genome Atlas (TCGA). Feature selection was performed using minimum redundancy maximum relevance (mRMR) and recursive feature elimination (RFE). Machine learning models were built to predict EGF/EGFR expression. Radiogenomic associations were validated by immune infiltration analysis. Patient-Derived Tumor-Like Cell Clusters (PTC) were used to compare the antitumor efficacy of EGFR- ADCs and temozolomide. RESULTS: Elevated EGF/EGFR expression correlated with poor prognosis and increased infiltration of M2 macrophages, regulatory T cells, and CD4⁺ memory T cells. Pathway analysis demonstrated significant enrichment of the mechanistic target of rapamycin (mTOR) and Mitogen-Activated Protein Kinase (MAPK) signaling cascades. Radiomics-based prediction models achieved robust performance (AUC > 0.85) in stratifying EGFR expression status. In EGFR-positive tumor tissues, EGFR-ADCs exerted antitumor efficacy similar to that of temozolomide. CONCLUSIONS: EGF/EGFR expression is associated with immunosuppressive microenvironments and adverse outcomes in HGG. Radiomics may provide a non-invasive approach for estimating EGFR expression, although model performance requires external validation and EGFR-ADCs showed partial inhibitory activity within the tested range, though potency remains to be defined.These findings suggest a framework into radiogenomic stratification and targeted therapy in GBM.

Radiomics↗

Terikalant and barium decrease the area of vulnerability to ventricular fibrillation induction by T-wave shocks.

The area of vulnerability (AOV) to ventricular fibrillation (VF) induction by high-voltage shocks has been proposed as a measure of vulnerability to VF. Biphasic shocks spanning the T wave and ranging between 50 V and the upper limit of vulnerability (ULV) to VF were delivered before and after terikalant (1 mg/kg) and barium (1.1 mg/kg load followed by 0.05-0.10 mg/kg/min maintenance) or vehicle in dogs. The AOV decreased by 34% and 28% (p < 0.01) after terikalant and barium (n = 8 dogs each), respectively. Mean ULV, defibrillation threshold (DFT), and ventricular vulnerability period (VVP) decreased by 16%, 23%, and 31% (p < 0.01), respectively, after terikalant, and by 25%, 17% (p < 0.01), and 13% (p = 0.08), respectively, after barium. Vehicle (n = 14) did not significantly alter any of these variables. The ULV was correlated with the DFT before and after terikalant (r = 0.78, p < 0.01) and barium (r = 0.83, p < 0.01). Potassium channel blockers of the current reduce the ability to induce VF; this effect may be related to the anti-fibrillatory action of class III anti-arrhythmic drugs and their ability to decrease DFT.

Action Potentials↗

Combination IK1 and IKr channel blockade: no additive lowering of the defibrillation threshold.

Selective blockade of the inward rectifier potassium channel I(K1) by barium, or of the rapidly activating delayed rectifier potassium channel I(Kr) by D,L-sotalol, prolongs repolarization and reduces the defibrillation threshold (DFT). This study hypothesized that combination I(K1) and I(Kr) channel block would produce concentration-dependent additive effects on DFT and ventricular refractoriness. A range of barium and D,L-sotalol concentrations, alone and in combination, were examined with respect to DFT, ventricular effective refractory period (VERP), and ventricular fibrillation cycle length (VFCL) in 133 Langendorff-perfused rabbit hearts. Barium produced a concentration-dependent reduction of DFT (-49+/-4%), with concentration-dependent increases in VERP (26+/-6%) and VFCL (42+/-18%). D,L-Sotalol produced a concentration-dependent lowering of DFT (-53+/-6%) with a concentration-dependent increase in VFCL (34+/-8%) but not VERP. Low (1.6 microM), intermediate (3.1 microM), and high (12.5 microM) barium concentrations combined with varying D,L-sotalol concentrations produced equal or smaller decreases in DFT compared with corresponding doses of barium or D,L-sotalol alone. Except at the lowest concentrations of barium (1.6 and 3.1 microM) (p < 0.05), there was no significant additive interaction between barium and D,L-sotalol on VERP or VFCL. Combination I(K1) and I(Kr) channel block by barium and D,L-sotalol does not produce additive reduction of DFT.

Algorithms↗