Paeciloquinone F

Purpose: The purpose of this study was to compare the primary staging of F-18 labeled fibroblast activation protein inhibitor ([18F]F-FAPI) with that of F-18 labeled fluordesoxyglucose positron emission tomography/computed tomography ([18F]F-FDG PET/CT) in patients with lung adenocarcinoma (LAD). Procedures: We prospectively analyzed the images of LAD patients who underwent [18F]F-FAPI and [18F]F-FDG PET/CT between May 2020 and August 2021. [18F]F-FAPI and [18F]F-FDG uptakes were compared using the paired samples t test, and lesion numbers were compared using the Wilcoxon signed-rank test. Results: Thirty-four LAD patients were evaluated. Patients showed high [18F]F-FAPI uptake in primary lesions (SUVmax 12.54 ± 3.77). Both [18F]F-FAPI and [18F]F-FDG had 100% detection rates for primary tumors. However, [18F]F-FAPI showed higher SUVmax than [18F]F-FDG in lesions of the lymph nodes, pleura, bones, and other tissues (all P ≤ 0.05). Although the absolute uptake values of [18F]F-FAPI in brain lesions were lower than those of [18F]F-FDG (1.56 ± 2.19 vs.7.34 ± 3.54, P < 0.0001), the tumor-to-background (T/B) ratios were significantly higher than those of [18F]F-FDG (9.53 ± 12.07 vs.1.01 ± 0.49, P < 0.0001). Generally, [18F]F-FAPI PET/CT could visualize more total lesions than [18F]F-FDG (554 vs.464, P = 0.003), especially in lymph nodes (258 vs.229, P = 0.039), the brain (34 vs.9, P = 0.002), and pleura (56 vs.30, P = 0.041). However, contrast-enhanced brain magnetic-resonance imaging (MRI) showed more brain lesions than [18F]F-FAPI PET/CT (56 vs.34, P = 0.002). Compared with the [18F]F-FDG-based TNM stage, the [18F]F-FAPI-based TNM stage was upgraded in six patients (17.6%). Conclusions: [18F]F-FAPI PET/CT showed a very high detection rate for primary LAD. In addition, 18F-FAPI PET/CT demonstrated clearer tumor delineation and more lesions than [18F]F-FDG PET/CT, especially in lymph nodes, the brain, and pleura. Therefore, [18F]F-FAPI had an advantage over [18F]F-FDG for primary staging of LAD. However, brain MRI could identify more and smaller lesions than [18F]F-FAPI PET/CT.

Recently, a straightforward one-pot method for 18F-fluoroethylation without azeotropic drying of cyclotron-produced [18F]F- was developed. In this study, we have attempted to simplify the automated radiosynthesis of two [18F]fluoroethylated tracers, [18F]FEDAC and [18F]FET, using a desmethyl labeling precursor and [18F]fluoroethyl tosylate, based on the above-mentioned method. The radiochemical yields of [18F]FEDAC and [18F]FET were 26 ± 3.7% (n = 5) and 14 ± 2.2% (n = 4), respectively, based on total [18F]F- at the end of irradiation.

Certain polyphenols exhibit low permeability; precise prediction of their intestinal absorption is important for understanding internal exposure in humans. Intestinal availability, which represents the fraction of administered compounds that reach the portal blood (FaFg), is calculated by dividing bioavailability (F) by hepatic availability (Fh), and F is obtained from pharmacokinetic data from both intravenous (i.v.) and oral (p.o.) administration. However, human FaFg of polyphenols is hardly reported, as human i.v. data are extremely scarce. In this study, we developed an estimation method for FaFg of polyphenols in humans based on the extrapolation of rat clearance using allometric scaling (allometric scaling-based FaFg calculation method, AS- FaFgCM). First, for quercetin, for which human i.v. data have been reported, we compared the FaFg obtained by AS-FaFgCM with the traditional approach using human i.v. and p.o. data. Less than two-fold difference in FaFg values was observed between the two approaches. Next, we obtained FaFg of structurally diverse polyphenols (genistein, baicalein, resveratrol, and epicatechin) using AS-FaFgCM, demonstrating that all of them were poorly absorbable. Furthermore, to utilize the pharmacokinetic data of the total concentration, including aglycones and metabolites, we modified the AS-FaFgCM to focus on their excretion. The FaFg value of naringenin was obtained using modified AS-FaFgCM and was nearly equal to that of baicalein, a structural isomer of naringenin. This study provides quantitative information on the intestinal absorption of polyphenols using comprehensive estimation methods.