Birkgregory3243
In mice, cellular senescence and senescence-associated secretory phenotype (SASP) positively contribute to cutaneous wound healing. In this proof-of-concept study, we investigated the expressions of p16, p21, and other senescence-associated biomarkers during human wound healing in 24 healthy subjects using a double-biopsy experimental design. The first punch biopsy created the wound and established the baseline. The second biopsy, concentric to the first and taken several days after wounding, was used to probe for expression of biomarkers by immunohistochemistry and RNA FISH. To assess the effects of age, we recruited 12 sex-matched younger (30.2 ± 1.3 years) and 12 sex-matched older (75.6 ± 1.8 years) subjects. We found that p21 and p53, but not p16, were induced during healing in younger, but not older subjects. A role for Notch signaling in p21 expression was inferred from the inducible activation of HES1. Further, other SASP biomarkers such as dipeptidyl peptidase-4 (DPP4) were significantly induced upon wounding in both younger and older groups, whereas matrix metallopeptidase 9 (MMP9) was induced only in the younger group. Senescence-associated β-galactosidase (SA-β-gal) was not detectable before or after wounding. This pilot study suggests the possibility that human cutaneous wound healing is characterized by differential expression of p21 and p53 between younger and older subjects.Transition-metal-catalyzed electrochemical C-H functionalizations have been extensively studied as atom- and step-economical clean methods in organic synthesis. In this account, we described our efforts on the palladium-catalyzed electrochemical C-H functionalizations, including C-H halogenations of arylpyridines and benzamide derivatives using HCl/HBr and I2 as a halogen source, a one-pot process giving teraryls via the palladium-catalyzed electrochemical C-H iodination and subsequent Suzuki-Miyaura coupling, and an iodine-mediated oxidative homo-coupling reaction of arylpyridines.Electrochemical doping of conducting polymers (CPs) generates polarons (radical ionic species) and bipolarons (ionic species) in their backbone via multi-electron transfer between an electrode and the CP. In the electrochemical polymer reaction (ePR), these generated ionic species are regarded as reactive intermediates for further transformation of the chemical structures of CPs. This electrochemical post-functionalization can easily be used to control the degree of reactions by turning a power supply on/off, as well as tuning the applied electrode potential, which leads to fine-tuning of the various properties of the CPs, such as the HOMO/LUMO level and PL properties. This Account summarizes recent developments in the electrochemical post-functionalization of CPs. In particular, we focus on reaction design for the ePR, with respect to the preparation and structure of the precursor polymers, applicable functional groups, efficient reaction conditions, and electrolytic methodologies.We report a late-stage heteroarylation of aryl sulfonium salts through activation with α-amino alkyl radicals in a mechanistically distinct approach from previously reported halogen-atom transfer (XAT). The new mode of activation of aryl sulfonium salts proceeds in the absence of light and photoredox catalysts, engaging a wide range of hetarenes. Furthermore, we demonstrate the applicability of this methodology in synthetically useful cross-coupling transformations.The COVID-19 pandemic led to an abrupt suspension of face-to-face teaching activities in higher education institutions across the globe. The instructors and faculty at most institutions have had to adapt, invent, and implement adjustments quickly to adopt an online learning environment. This has been an extraordinarily challenging time for both students and instructors, particularly as many were not aware of the affordances and weaknesses of the online learning environment before it was uptaken. Particularly for chemistry and related disciplines, this change in delivery mode is even more disruptive in courses that have laboratory components due to loss of access to laboratories. As a teaching community, it was our responsibility to respond quickly and effectively to students' learning needs during this unprecedented global crisis. In our course, we provided succinct pre-recorded lecture-videos by topic rather than live-streaming of lectures. The recordings were made available to students a minimum of 24 h before the scheduled lecture time. Students were then provided opportunities to attend live tutorial sessions (held on Zoom and live Q&A feature on Piazza) if they had any questions that they wanted to ask the lecturer directly. We believe that the asynchronous sessions were more equitable than synchronous ones. This meant that students with difficult and challenging home/learning environments (i.e., disruptions at home, work/family schedules, poor internet, limited access to devices, etc.) were minimally disadvantaged. The approach worked well in general for teaching chemistry to pharmacy students and we believe that it can be adopted for other subjects.Seedlessness in grapes is one of the features most appreciated by consumers. However, the mechanisms underlying seedlessness in grapes remain obscure. Here, we observe small globular embryos and globular embryos in Pinot Noir and Thompson Seedless from 20 to 30 days after flowering (DAF). From 40 to 50 DAF, we observe torpedo embryos and cotyledon embryos in Pinot Noir but aborted embryos and endosperm in Thompson Seedless. Thus, RNA-Seq analyses of seeds at these stages from Thompson Seedless and Pinot Noir were performed. A total of 6442 differentially expressed genes were identified. Among these, genes involved in SA biosynthesis, VvEDS1 and VvSARD1, were more highly expressed in Thompson Seedless than in Pinot Noir. Moreover, the content of endogenous SA is at least five times higher in Thompson Seedless than in Pinot Noir. selleckchem Increased trimethylation of H3K27 of VvEDS1 and VvSARD1 may be correlated with lower SA content in Pinot Noir. We also demonstrate that VvHDZ28 positively regulates the expression of VvEDS1.