RESUMO
The conserved pterin dithiolene ligand that coordinates molybdenum (Mo) in the cofactor (Moco) of mononuclear Mo enzymes can exist in both a tricyclic pyranopterin dithiolene form and as a bicyclic pterin-dithiolene form as observed in protein crystal structures of several bacterial molybdoenzymes. Interconversion between the tricyclic and bicyclic forms via pyran scission and cyclization has been hypothesized to play a role in the catalytic mechanism of Moco. Therefore, understanding the interconversion between the tricyclic and bicyclic forms, a type of ring-chain tautomerism, is an important aspect of study to understand its role in catalysis. In this study, equilibrium constants (K(eq)) as well as enthalpy, entropy, and free energy values are obtained for pyran ring tautomerism exhibited by two Moco model complexes, namely, (Et4N)[Tp*Mo(O)(S2BMOPP)] (1) and (Et4N)[Tp*Mo(O)(S2PEOPP)] (2), as a solvent-dependent equilibrium process. Keq values obtained from (1)H NMR data in seven deuterated solvents show a correlation between solvent polarity and tautomer form, where solvents with higher polarity parameters favor the pyran form.
Assuntos
Coenzimas/química , Molibdênio/química , Compostos Organometálicos/química , Pterinas/química , Solventes/química , Ciclização , Modelos Moleculares , Estrutura Molecular , Compostos Organometálicos/síntese química , Teoria Quântica , TermodinâmicaRESUMO
OBJECTIVE: We aimed to assess the feasibility, clinical accuracy, and acceptance of a hospital-wide continuous glucose monitoring (CGM) policy with electronic health record (EHR)-integrated validation for insulin dosing. RESEARCH DESIGN AND METHODS: A hospital policy was developed and implemented at Stanford Health Care for using personal CGMs in lieu of fingerstick blood glucose (FSBG) monitoring. It included requirements specific to each CGM, accuracy monitoring protocols, and EHR integration. User experience surveys were conducted among a subset of patients and nurses. RESULTS: From November 2022 to August 2023, 135 patients used the CGM protocol in 185 inpatient encounters. This group included 27% with type 1 diabetes and 24% with automated insulin delivery systems. The most-used CGMs were Dexcom G6 (44%) and FreeStyle Libre 2 (43%). Of 1,506 CGM validation attempts, 87.8% met the 20% or 20 mg/dL (%20/20) criterion for CGM-based insulin dosing and 99.3% fell within Clarke zones A or B. User experience surveys were completed by 27 nurses and 46 patients. Most nurses found glucose management under the protocol effective (74%), easy to use (67%), and efficient (63%); 80% of nurses preferred inpatient CGM to FSBG. Most patients liked the CGM protocol (63%), reported positive CGM interactions with nursing staff (63%), and felt no significant interruptions to their diabetes management (63%). CONCLUSIONS: Implementation of a hospital-wide inpatient CGM policy supporting multiple CGM types with real-time accuracy monitoring and integration into the EHR is feasible. Initial feedback from nurses and patients was favorable, and further investigation toward broader use and sustainability is needed.