Dynamics of Oxygen-Independent Photocleavage of Blebbistatin as a One-Photon Blue or Two-Photon Near-Infrared Light-Gated Hydroxyl Radical Photocage

Development of versatile, chemically tunable photocages for photoactivated chemotherapy (PACT) represents an excellent opportunity to address the technical drawbacks of conventional photodynamic therapy (PDT) whose oxygen-dependent nature renders it inadequate in certain therapy contexts such as hypoxic tumors. As an alternative to PDT, oxygen free mechanisms to generate cytotoxic reactive oxygen species (ROS) by visible light cleavable photocages are in demand. Here, we report the detailed mechanisms by which the small molecule blebbistatin acts as a one-photon blue light-gated or two-photon near-infrared light-gated photocage to directly release a hydroxyl radical (•OH) in the absence of oxygen. By using femtosecond transient absorption spectroscopy and chemoselective ROS fluorescent probes, we analyze the dynamics and fate of blebbistatin during photolysis under blue light. Water-dependent photochemistry reveals a critical process of water-assisted protonation and excited state intramolecular proton transfer (ESIPT) that drives the formation of short-lived intermediates, which surprisingly culminates in the release of •OH but not superoxide or singlet oxygen from blebbistatin. CASPT2//CASSCF calculations confirm that hydrogen bonding between water and blebbistatin underpins this process. We further determine that blue light enables blebbistatin to induce mitochondria-dependent apoptosis, an attribute conducive to PACT development. Our work demonstrates blebbistatin as a controllable photocage for •OH generation and provides insight into the potential development of novel PACT agents

Co-function Mechanisms of Chlorine and Alkoxy Radicals in Cerium-Catalyzed C–H Functionalization of Alkane Mediated by Visible Light

Identification of radical intermediates for the catalytic functionalization of alkanes offers a number of unique challenges and has recently raised a controversial issue concerning the subtle role of chlorine versus alkoxy radicals in cerium photocatalysis. This study is an attempt to settle the controversy within the theoretical frameworks of Marcus electron transfer and transition state theory. Co-function mechanisms were proposed together with a scheme of kinetic evaluations to account for ternary dynamic competition among photolysis, back electron transfer, and hydrogen atom transfer (HAT). Cl•-based HAT has been proven to initially control the early dynamics of the photocatalytic transformation on the picosecond to nanosecond time scale, which is subsequently taken over by a postnanosecond event of alkoxy radical-mediated HAT. The theoretical models developed herein provide a uniform understanding of the continuous time dynamics of photogenerated radicals to address some paradoxical arguments in lanthanide photocatalysis

Additional file 1 of The neutrophil–lymphocyte ratio as a risk factor for all-cause and cardiovascular mortality among individuals with diabetes: evidence from the NHANES 2003–2016

Additional file 1: Figure S1. The flow chart of participants inclusion and exclusion in the NHANES 2003–2010

pH and Reduction Dual-Bioresponsive Polymersomes for Efficient Intracellular Protein Delivery

pH and reduction dual-bioresponsive nanosized polymersomes based on poly­(ethylene glycol)-SS-poly­(2-(diethyl amino)­ethyl methacrylate) (PEG-SS-PDEA) diblock copolymers were developed for efficient encapsulation and triggered intracellular release of proteins. PEG-SS-PDEA copolymers with PDEA-block molecular weights ranging from 4.7, 6.8, to 9.2 kg/mol were synthesized in a controlled manner via reversible addition–fragmentation chain transfer (RAFT) polymerization of 2-(diethyl amino)­ethyl methacrylate (DEAEMA) using PEG-SS-CPADN (CPADN = 4-cyanopentanoic acid dithionaphthalenoate; <i>M</i>_n PEG = 1.9 kg/mol) as a macro-RAFT agent. These copolymers existed as unimers in water at mildly acidic pH (<7.2) conditions, but readily formed monodisperse nanosized polymersomes (54.5–66.8 nm) when adjusting solution pH to 7.4. These polymersomes were highly sensitive to intracellular pH and reductive environments, which resulted in fast dissociation and aggregation of polymersomes, respectively. Notably, both fluorescein isothiocyanate (FITC)-labeled bovine serum albumin (FITC-BSA) and cytochrome C (FITC-CC) proteins could facilely be encapsulated into polymersomes with excellent protein-loading efficiencies, likely as a result of electrostatic interactions between proteins and PDEA. The in vitro release studies showed that protein release was minimal (<20% in 8 h) at pH 7.4 and 37 °C. The release of proteins was significantly enhanced at pH 6.0 due to collapse of polymersomes. Notably, the fastest protein release was observed under intracellular-mimicking reductive environments (10 mM dithiothreitol, pH 7.4). MTT assays in RAW 264.7 and MCF-7 cells indicated that PEG-SS-PDEA (9.2 k) polymersomes had low cytotoxicity up to a polymer concentration of 300 μg/mL. Confocal laser scanning microscope (CLSM) observations revealed that FITC-CC-loaded PEG-SS-PDEA (9.2 k) polymersomes efficiently delivered and released proteins into MCF-7 cells following 6 h of incubation. Importantly, flow cytometry assays showed that CC-loaded PEG-SS-PDEA (9.2 k) polymersomes induced markedly enhanced apoptosis of MCF-7 cells as compared to free CC and CC-loaded PEG–PDEA (8.9 k) polymersomes (reduction-insensitive control). These dual-bioresponsive polymersomes have appeared to be highly promising for intracellular delivery of protein drugs

Image8_Identification of DDX31 as a Potential Oncogene of Invasive Metastasis and Proliferation in PDAC.TIF

Background: Pancreatic ductal adenocarcinoma (PDAC) is one of the deadliest malignant tumors worldwide and has poor prognosis. DEAD box proteins31 (DDX31) participate in cellular processes involving RNA secondary structure changes. However, the functions of DDX31 in PDAC remain to be elucidated.Methods: The key gene DDX31 was identified using a combination of a risk model and weighted gene co-expression network analysis (WGCNA) with R software. The biological functions of DDX31 in PDAC were investigated through bioinformatics analysis and in vitro experiments.Results: Combining with WGCNA and risk model, DDX31 was identified as a potential factor of the invasive metastasis properties of PDAC, and its expression was closely related to the malignant differentiation of PDAC. The results of gene set enrichment analysis (GSEA) showed that DDX31 was correlated with cell invasive metastasis and proliferation by activating MAPK signaling pathway. The inhibition of DDX31 inhibited the invasion and migration of PDAC cells. Survival analysis showed that DDX31 expression was negatively associated with the poor prognosis in patients with PDAC.Interpretation:DDX31 may be a potential factor for PDAC. The inhibition of DDX31 may be a potential way to treat PDAC.</p

Table8_Identification of DDX31 as a Potential Oncogene of Invasive Metastasis and Proliferation in PDAC.XLS

Background: Pancreatic ductal adenocarcinoma (PDAC) is one of the deadliest malignant tumors worldwide and has poor prognosis. DEAD box proteins31 (DDX31) participate in cellular processes involving RNA secondary structure changes. However, the functions of DDX31 in PDAC remain to be elucidated.Methods: The key gene DDX31 was identified using a combination of a risk model and weighted gene co-expression network analysis (WGCNA) with R software. The biological functions of DDX31 in PDAC were investigated through bioinformatics analysis and in vitro experiments.Results: Combining with WGCNA and risk model, DDX31 was identified as a potential factor of the invasive metastasis properties of PDAC, and its expression was closely related to the malignant differentiation of PDAC. The results of gene set enrichment analysis (GSEA) showed that DDX31 was correlated with cell invasive metastasis and proliferation by activating MAPK signaling pathway. The inhibition of DDX31 inhibited the invasion and migration of PDAC cells. Survival analysis showed that DDX31 expression was negatively associated with the poor prognosis in patients with PDAC.Interpretation:DDX31 may be a potential factor for PDAC. The inhibition of DDX31 may be a potential way to treat PDAC.</p

Table2_Identification of DDX31 as a Potential Oncogene of Invasive Metastasis and Proliferation in PDAC.XLSX

Background: Pancreatic ductal adenocarcinoma (PDAC) is one of the deadliest malignant tumors worldwide and has poor prognosis. DEAD box proteins31 (DDX31) participate in cellular processes involving RNA secondary structure changes. However, the functions of DDX31 in PDAC remain to be elucidated.Methods: The key gene DDX31 was identified using a combination of a risk model and weighted gene co-expression network analysis (WGCNA) with R software. The biological functions of DDX31 in PDAC were investigated through bioinformatics analysis and in vitro experiments.Results: Combining with WGCNA and risk model, DDX31 was identified as a potential factor of the invasive metastasis properties of PDAC, and its expression was closely related to the malignant differentiation of PDAC. The results of gene set enrichment analysis (GSEA) showed that DDX31 was correlated with cell invasive metastasis and proliferation by activating MAPK signaling pathway. The inhibition of DDX31 inhibited the invasion and migration of PDAC cells. Survival analysis showed that DDX31 expression was negatively associated with the poor prognosis in patients with PDAC.Interpretation:DDX31 may be a potential factor for PDAC. The inhibition of DDX31 may be a potential way to treat PDAC.</p

Image7_Identification of DDX31 as a Potential Oncogene of Invasive Metastasis and Proliferation in PDAC.TIF

Background: Pancreatic ductal adenocarcinoma (PDAC) is one of the deadliest malignant tumors worldwide and has poor prognosis. DEAD box proteins31 (DDX31) participate in cellular processes involving RNA secondary structure changes. However, the functions of DDX31 in PDAC remain to be elucidated.Methods: The key gene DDX31 was identified using a combination of a risk model and weighted gene co-expression network analysis (WGCNA) with R software. The biological functions of DDX31 in PDAC were investigated through bioinformatics analysis and in vitro experiments.Results: Combining with WGCNA and risk model, DDX31 was identified as a potential factor of the invasive metastasis properties of PDAC, and its expression was closely related to the malignant differentiation of PDAC. The results of gene set enrichment analysis (GSEA) showed that DDX31 was correlated with cell invasive metastasis and proliferation by activating MAPK signaling pathway. The inhibition of DDX31 inhibited the invasion and migration of PDAC cells. Survival analysis showed that DDX31 expression was negatively associated with the poor prognosis in patients with PDAC.Interpretation:DDX31 may be a potential factor for PDAC. The inhibition of DDX31 may be a potential way to treat PDAC.</p

Table5_Identification of DDX31 as a Potential Oncogene of Invasive Metastasis and Proliferation in PDAC.XLS

Background: Pancreatic ductal adenocarcinoma (PDAC) is one of the deadliest malignant tumors worldwide and has poor prognosis. DEAD box proteins31 (DDX31) participate in cellular processes involving RNA secondary structure changes. However, the functions of DDX31 in PDAC remain to be elucidated.Methods: The key gene DDX31 was identified using a combination of a risk model and weighted gene co-expression network analysis (WGCNA) with R software. The biological functions of DDX31 in PDAC were investigated through bioinformatics analysis and in vitro experiments.Results: Combining with WGCNA and risk model, DDX31 was identified as a potential factor of the invasive metastasis properties of PDAC, and its expression was closely related to the malignant differentiation of PDAC. The results of gene set enrichment analysis (GSEA) showed that DDX31 was correlated with cell invasive metastasis and proliferation by activating MAPK signaling pathway. The inhibition of DDX31 inhibited the invasion and migration of PDAC cells. Survival analysis showed that DDX31 expression was negatively associated with the poor prognosis in patients with PDAC.Interpretation:DDX31 may be a potential factor for PDAC. The inhibition of DDX31 may be a potential way to treat PDAC.</p

Image4_Identification of DDX31 as a Potential Oncogene of Invasive Metastasis and Proliferation in PDAC.TIF

Background: Pancreatic ductal adenocarcinoma (PDAC) is one of the deadliest malignant tumors worldwide and has poor prognosis. DEAD box proteins31 (DDX31) participate in cellular processes involving RNA secondary structure changes. However, the functions of DDX31 in PDAC remain to be elucidated.Methods: The key gene DDX31 was identified using a combination of a risk model and weighted gene co-expression network analysis (WGCNA) with R software. The biological functions of DDX31 in PDAC were investigated through bioinformatics analysis and in vitro experiments.Results: Combining with WGCNA and risk model, DDX31 was identified as a potential factor of the invasive metastasis properties of PDAC, and its expression was closely related to the malignant differentiation of PDAC. The results of gene set enrichment analysis (GSEA) showed that DDX31 was correlated with cell invasive metastasis and proliferation by activating MAPK signaling pathway. The inhibition of DDX31 inhibited the invasion and migration of PDAC cells. Survival analysis showed that DDX31 expression was negatively associated with the poor prognosis in patients with PDAC.Interpretation:DDX31 may be a potential factor for PDAC. The inhibition of DDX31 may be a potential way to treat PDAC.</p