OBJECTIVES: In Korea, the National Health Insurance Service (NHIS) covers essential healthcare expenses, including cataract surgery. To address concerns that private health insurance (PHI) might have inflated the need for such procedures, we investigated the extent of the PHI-attributable increase in cataract surgery and its impact on NHIS-reimbursed expenses. METHODS: This retrospective, observational study uses nationwide claims data for cataract surgery from 2016 to 2020. We examined trends in utilization and cost, and we estimated the excess numbers of (1) cataract operations attributable to PHI and (2) types of intraocular lenses used for cataract surgery in 2020. RESULTS: Between 2016 and 2020, a 36.8% increase occurred in the number of cataract operations, with increases of 63.5% and 731.8% in the total healthcare costs reimbursed by NHIS and PHI, respectively. Over a 5-year period, the surgical rate per 100,000 people doubled for patients aged <65 years (from 328 in 2016 to 664 in 2020). Among the 619,771 cases in 2020 of cataract surgery reimbursed by the Korean diagnosis-related group system, more non-NHIS-covered intraocular lenses were used for patients aged <65 years than ≥65 years (68.1 vs. 14.2%). In 2020 alone, an estimated 129,311 excess operations occurred, accounting for an excess cost of US$115 million. CONCLUSIONS A dramatic increase in the number and cost of cataract operations has occurred over the last 5 years. The PHI-related increase in operations resulted in increased costs to NHIS. Measures to curtail the non-indicated use of cataract surgery should be implemented regarding PHI.

Mechanistic target of rapamycin (mTOR) complex 1 (mTORC1) integrates signals from growth factors, cellular energy levels, stress and amino acids to control cell growth and proliferation through regulating translation, autophagy and metabolism. Here we determined the cryo-electron microscopy structure of human mTORC1 at 4.4 Å resolution. The mTORC1 comprises a dimer of heterotrimer (mTOR-Raptor-mLST8) mediated by the mTOR protein. The complex adopts a hollow rhomboid shape with 2-fold symmetry. Notably, mTORC1 shows intrinsic conformational dynamics. Within the complex, the conserved N-terminal caspase-like domain of Raptor faces toward the catalytic cavity of the kinase domain of mTOR. Raptor shows no caspase activity and therefore may bind to TOS motif for substrate recognition. Structural analysis indicates that FKBP12-Rapamycin may generate steric hindrance for substrate entry to the catalytic cavity of mTORC1. The structure provides a basis to understand the assembly of mTORC1 and a framework to characterize the regulatory mechanism of mTORC1 pathway.
Cell Line ; Cryoelectron Microscopy ; methods ; Humans ; Mechanistic Target of Rapamycin Complex 1 ; Multiprotein Complexes ; chemistry ; ultrastructure ; Protein Structure, Quaternary ; TOR Serine-Threonine Kinases ; chemistry ; ultrastructure