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We report the C–F bond heteroarylation of trifluoromethylarenes with heteroarenes by using Ir(ppy)3 catalyst and Bu3 SnI under visible-light irradiation. Various heteroarenes such as pyrrole, furan, and thiophene derivatives were applied to the present reaction. The present heteroarylation enables the transformation of various functionalized trifluoromethylarenes because of the mild reaction conditions. Notably, the late-stage transformation of a drug molecule, bicalutamide, was demonstrated. Mechanistic studies including a light on–off interval experiment, Stern–Volmer luminescence-quenching measurements, and DFT calculations clarified two critical roles of Bu3 SnI for the successful progress of the heteroarylation. Bu3 SnI functions as a fluoride ion scavenger to suppress the undesired C–F bond re-formation. Bu3 SnI also acts as a single-electron source for the reduction of photoexcited Ir(ppy)3 * to generate Ir(II) species to effectively reduce ArCF3. [ABSTRACT FROM AUTHOR]

Sodium monofluorophosphate (Na2FPO3, MFP) is mainly used as an ingredient in fluoride-based dentifrices as it has a high safety profile, with one-third of the toxicity of sodium fluoride (NaF), as well as the ability to reach deep into the dentin. The purpose of this study was to assess the prevention of dentin erosion by MFP upon exposure to citric acid, which has a chelating effect, and to compare the effects to those of the conventional acidulated phosphate fluoride (APF) application method. Bovine dentin was used, and four groups were created: (i) APF (9000 ppmF, pH 3.6) 4 min group; (ii) acidulated phosphate MFP (AP-MFP, 9000 ppmF, pH 3.6) 4 min group; (iii) AP-MFP 2 min + APF 2 min (dual) group; and (iv) no fluoride application (control) group. Compared with the conventional APF application method, the application of AP-MFP was shown to significantly reduce substantial defects, mineral loss, and lesion depth; better maintain Vickers hardness; and promote the homogenous aggregation of fine CaF2 particles to seal the dentin tubules, enhancing acid resistance in their vicinity. The ΔZ value of the AP-MFP group was 2679 ± 290.2 vol% μm, significantly smaller than the APF group's 3806 ± 257.5 vol% μm (p < 0.01). Thus, AP-MFP-based fluoride application could effectively suppress citric acid-induced demineralization and could become a new, more powerful, and biologically safer professional-care method for preventing acid-induced dentin erosion than the conventional method. [ABSTRACT FROM AUTHOR]

This study aimed to develop an automated pH-cycling system using inexpensive commercial components that can replicate pH fluctuations in the oral cavity and salivary clearance to compare demineralization characteristics with the conventional method. The study found that the newly developed cycle-1 group showed improved demineralization properties, including apparent lesion depth, surface roughness, Vickers hardness, mineral loss, and depth of demineralization, compared to the control group. Additionally, the cycle-2 group, which had a longer cycle interval, showed further improvements in the demineralization properties. This system can replicate the differences in dental damage caused by differences in meals, snacking frequencies, and lifestyle rhythms, making it useful in cariology, preventive dentistry research, and oral care product development. It can be constructed using inexpensive commercial products, significantly reducing research costs and improving reproducibility and fairness between different experimental facilities. The system can replicate lifestyle rhythms, such as meals, sleep, and oral clearance by saliva, making it an in vitro pseudo-oral cavity. [ABSTRACT FROM AUTHOR]

Background: The need for quantitative assessment of interstitial lung involvement on thin-section computed tomography (CT) has arisen in interstitial lung diseases including connective tissue disease (CTD). Purpose: To evaluate the capability of machine learning (ML)-based CT texture analysis for disease severity and treatment response assessments in comparison with qualitatively assessed thin-section CT for patients with CTD. Material and Methods: A total of 149 patients with CTD-related ILD (CTD-ILD) underwent initial and follow-up CT scans (total 364 paired serial CT examinations), pulmonary function tests, and serum KL-6 level tests. Based on all follow-up examination results, all paired serial CT examinations were assessed as "Stable" (n = 188), "Worse" (n = 98) and "Improved" (n = 78). Next, quantitative index changes were determined by software, and qualitative disease severity scores were assessed by consensus of two radiologists. To evaluate differences in each quantitative index as well as in disease severity score between paired serial CT examinations, Tukey's honestly significant difference (HSD) test was performed among the three statuses. Stepwise regression analyses were performed to determine changes in each pulmonary functional parameter and all quantitative indexes between paired serial CT scans. Results: Δ% normal lung, Δ% consolidation, Δ% ground glass opacity, Δ% reticulation, and Δdisease severity score showed significant differences among the three statuses (P < 0.05). All differences in pulmonary functional parameters were significantly affected by Δ% normal lung, Δ% reticulation, and Δ% honeycomb (0.16 ≤r2 ≤0.42; P < 0.05). Conclusion: ML-based CT texture analysis has better potential than qualitatively assessed thin-section CT for disease severity assessment and treatment response evaluation for CTD-ILD. [ABSTRACT FROM AUTHOR]

Due to its large bond energy, precisely controllable C–F bond activation is a significant challenge in organic synthesis. A single C(sp3)–F bond transformation of perfluoroalkyl groups is particularly desirable to supply functionalized perfluoroalkyl compounds offering properties that are potentially useful in pharmaceutical and materials chemistry. Recently, the single defluorinative transformation of perfluoroalkyl compounds has been developed via visible-light photocatalysis. Herein, we summarize this field via two main topics. Topic 1 covers the transformations of C(sp3)–F bonds in either perfluoroalkylarenes or perfluoroalkane carbonyl compounds via a defluorinative spin-center shift in the radical anion intermediates. Topic 2 addresses the defluorinative transformations of α-trifluoromethyl alkenes to give gem -difluoroalkenes via a radical/polar crossover process. 1 Introduction 2 C(sp3)–F Transformations via Defluorinative Spin-Center Shifts 3 C(sp3)–F Transformations via a Radical/Polar Crossover Process 4 Conclusions [ABSTRACT FROM AUTHOR]