Shuguang Hospital

To evaluate the technical feasibility and clinical outcomes of flexible and navigable suction ureteral access sheath (FANS) combined with flexible ureteroscopy (fURS) for proximal impacted ureter stones (PIUS) and identify predictors of residual fragments (RF).

This single-center retrospective study included 45 patients with PIUS who underwent FANS-fURS (August 2023-February 2025). The surgical procedure involved FANS deployment, laser lithotripsy, and real-time suction-assisted fragment clearance. Stone-free status (SFS) was assessed at 30 days postoperatively, with Grades B-D defined as RF. Multivariate logistic regression analyzed predictors of RF.

The median age was 55 years (IQR: 41.5-61.5), with 71.1% male. Postoperative SFS were Grade A (40.00%), B (51.11%), C (6.67%), and D (2.22%). Multivariate analysis identified larger sheath size as protective against RF (OR: 0.061, P = 0.025), while larger stone diameter (OR: 1.593, P = 0.031) and higher polyp occupancy within the lumen (OR: 1.919, P = 0.040) increased RF risk. Median operative time was 42 min (IQR: 33.5-65.0).

The combination of FANS and fURS demonstrated high efficacy in managing PIUS, achieving favorable stone clearance rates. Sheath size, stone diameter, and polyp occupancy within the lumen are significant predictors of RF, which can help optimize surgical strategy.

G protein-coupled receptors (GPCRs), the largest family of membrane proteins, serve as primary targets for over 30% of FDA-approved drugs. While signaling bias among Gα subtypes is well characterized, emerging evidence highlights that Gβγ subtypes govern the coupling of the Gα heterotrimer to GPCRs. However, whether Gβγ subtype selectivity depends on the receptor or the Gα subunit and the underlying mechanism remain unresolved. Here, we focused on Gαq-coupled GPCRs and investigated Gβγ preferences using bioluminescence resonance energy transfer assays to assess Gβγ selectivity along with Gαq-GPCR coupling and calcium flux assays to measure downstream Ca²⁺ mobilization. By characterizing seven Gαq-coupled receptors, including the muscarinic acetylcholine receptor family (M1 mAChR, M3 mAChR, M5 mAChR) and four other Gαq-coupled GPCRs (AT1R, NTSR1, KISS1R, hM3Dq), the Gβ1/2γ2 combinations were identified as the preferred subtypes for Gαq coupling. Structural analysis and site-directed mutagenesis assays revealed that three key residues in Gβ2 (F111, V178, and G179), distinct from Gβ4, are crucial for enhancing Gαq coupling. Notably, Gβ4 exhibited preferential recruitment of the Gαq heterotrimer in response to pilocarpine relative to acetylcholine, suggesting that pilocarpine may function as a Gβ4-biased agonist. These findings advance our understanding of Gβγ-mediated subtype selectivity and open avenues for developing biased ligands in drug discovery.

Mutations in mitogen‐activated protein kinase kinase (MEK) are prevalent in pancreatic ductal adenocarcinoma (PDAC), but many MEK inhibitors inadvertently activate protein kinase B (AKT). We propose a promising PDAC treatment strategy by combining the MEK inhibitor trametinib with neobractatin (NBT), a natural compound from Garcinia bracteata. Our results demonstrated that this combination significantly impeded cell growth by inducing gasdermin E (GSDME)‐mediated pyroptosis and apoptosis. GSDME, overexpressed in PDAC tissues and correlated with histological differentiation, underscores the role of pyroptosis in PDAC. RNA‐seq results indicated that the phosphoinositide 3‐kinase/protein kinase B (PI3K/AKT) pathway was the primary target of the combination treatment. Mechanistic studies revealed the combination effectively reduced both total and phosphorylated AKT levels, thereby inhibiting protein kinase B/IκB kinase (AKT/IKK) and protein kinase B/mammalian target of rapamycin (AKT/mTOR) signaling pathways. Additionally, the combination disrupted mTOR complex 2 (mTORC2), preventing the trametinib‐induced AKT activation. MicroRNA sequencing analysis indicated that the combination reduced AKT levels by upregulated miR‐149‐5p. Further research demonstrated that the combination increased intracellular reactive oxygen species (ROS), while N‐acetylcysteine (NAC, a ROS scavenger) reversed the cell growth inhibition and AKT suppression. In vivo, the combination significantly inhibited tumor growth by inducing pyroptosis and apoptosis, outperforming gemcitabine. Our findings provide novel insights into the potential of combining NBT and trametinib to induce pyroptosis and apoptosis through the ROS/AKT/GSDME axis, offering a theoretical basis for future PDAC treatment.