RESUMEN
Highly electrophilic aryl(2,2,2-trifluoroethyl)iodonium triflates have been used for the first time as trifluoroethyl and aryl transfer reagents in Pd-catalyzed functionalization of arylboronic acids. Electron-rich arylboronic acids reacted with aryl(2,2,2-trifluoroethyl)iodonium triflates (2a-b) in CH3CN in the presence of Pd2(dba)3 and K3PO4 at room temperature to provide trifluoroethyl arenes in up to 82% yield, while the reactions of both electron-rich and -poor arylboronic acids with 2a-b in DMF in the presence of Pd[P(t-Bu)3]2 and Cs2CO3 at 40 °C afforded arylation products in up to 99% yield. This tunable protocol allows access to trifluoroethyl arenes or biaryls in good to excellent yields under mild conditions and without the addition of extra ligands.
RESUMEN
Objective: Late 2019 witnessed the outbreak and widespread transmission of coronavirus disease 2019 (COVID-19), a new, highly contagious disease caused by novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Consequently, considerable attention has been paid to the development of new diagnostic tools for the early detection of SARS-CoV-2. Methods: In this study, a new poly-N-isopropylacrylamide microgel-based electrochemical sensor was explored to detect the SARS-CoV-2 spike protein (S protein) in human saliva. The microgel was composed of a copolymer of N-isopropylacrylamide and acrylic acid, and gold nanoparticles were encapsulated within the microgel through facile and economical fabrication. The electrochemical performance of the sensor was evaluated through differential pulse voltammetry. Results: Under optimal experimental conditions, the linear range of the sensor was 10 -13-10 -9 mg/mL, whereas the detection limit was 9.55 fg/mL. Furthermore, the S protein was instilled in artificial saliva as the infected human saliva model, and the sensing platform showed satisfactory detection capability. Conclusion: The sensing platform exhibited excellent specificity and sensitivity in detecting spike protein, indicating its potential application for the time-saving and inexpensive detection of SARS-CoV-2.
Asunto(s)
COVID-19 , Nanopartículas del Metal , Microgeles , Humanos , Glicoproteína de la Espiga del Coronavirus , COVID-19/diagnóstico , Oro , SARS-CoV-2RESUMEN
OBJECTIVE: To compare the medical expenditure and its trend for diabetes mellitus and non-diabetes mellitus and to assess the direct economic burden of diabetes for individuals and families. METHODS: Using data from the China Health and Nutrition Survey(CHNS), propensity scores matching(PSM)was used to match diabetes mellitus and non-diabetes mellitus according to the related characteristic variables. Data from 679 pairs of objects was then compared. RESULTS: From 2000 to 2009, gaps of annual medical expenditure from diabetes mellitus and non-diabetes mellitus showed an increase, from 3361.93 to 6608.48 Yuan, with the ratios of medical expenditure about 4 times. The ratios of personal economic burden and family economic burden had an increase of about 4-5 times. CONCLUSION: Compared with non-diabetes mellitus, the annual medical expenses was significantly higher among patients with diabetes mellitus. The absolute cost appeared a dramatic increase, along with the personal and familiar economic burden.