The generation of long-chain alkoxy radicals visible light-induced energy transfer (EnT) has been accomplished through the design of a new class of bifunctional oxime esters derived from iminophenylacetic acid. The 1,5-hydrogen atom abstraction (HAT) of the alkoxy radicals, followed by alkylamination of alkenes, enables the construction of a 1,6-linkage across a double bond to obtain the valuable 1,6-amino alcohols.
View Article and Find Full Text PDFA photoinduced EnT-mediated generation of sulfonamidyl radicals has been accomplished using rationally designed iminophenylacetic acid oxime ester reagents under metal-free conditions. This approach offers a mild, regio- and diastereoselective synthesis of -sulfonyl diamines diamination of alkenes and (hetero)arenes.
View Article and Find Full Text PDFGold-catalyzed regioselective hydrofluorination of alkynes using aqueous HF has been achieved by employing an amide directing group. For both aryl- and alkyl-substituted propargylamines, the fluorination occurred at the site distal to the amino group.
View Article and Find Full Text PDFThe hydroxyl group was discovered to promote gold catalyzed hydrofluorination of alkynes hydrogen bonding interaction. Based on this strategy, propargyl alcohols could be hydrofluorinated smoothly using EtN·3HF under acidic additive-free conditions, which provided a straightforward alternative protocol for the synthesis of 3-fluoroallyl alcohols.
View Article and Find Full Text PDFPivalic anhydride is shown to be an effective reagent for direct amidation of carboxylic acids with -alkyl anilines. The only by-product of this reaction is nontoxic pivalic acid, which can be easily removed by aqueous workup. The reactions are conducted under mild conditions and found to be compatible with a range of carboxylic acids, including aromatic, heterocyclic, acrylic, and aliphatic carboxylic acids and amino acids generating the desired amides in short reaction times.
View Article and Find Full Text PDFThe bottleneck of large-scale implementation of electrocatalytic water-splitting technology lies in lacking inexpensive, efficient, and durable catalysts to accelerate the sluggish oxygen evolution reaction kinetics. Owing to more metallic features, transition metal telluride (TMT) with good electronic conductivity holds promising potential as an ideal type of electrocatalysts for oxygen evolution reaction (OER), whereas most TMTs reported up to now still show unsatisfactory OER performance that is far below corresponding sulfide and selenide counterparts. Here, the activation and stabilization of cobalt telluride (CoTe) nanoarrays toward OER through dual integration of sulfur (S) doping and surface oxidization is reported.
View Article and Find Full Text PDFA complementary and general strategy for the oxidative generation of iminyl radicals from the readily available α-imino-oxy acids has been established through silver-catalyzed decarboxylation. To demonstrate its synthesis utility, the direct C-H cyanoalkylation of heterocycles and quinones with cyclic α-imino-oxy acids via the iminyl radical-mediated C-C bond cleavage is developed. This cost-effective method takes place under mild reaction conditions and exhibits a broad substrate scope.
View Article and Find Full Text PDFA general and efficient oxyhalogenation of unsaturated ketoximes has been achieved through copper catalysis with diethyl bromomalonate, N-chlorosuccinimide, and N-iodosuccinimide, yielding 5-chloromethyl, 5-bromomethyl, and 5-iodomethyl isoxazolines in good to excellent yields.
View Article and Find Full Text PDFBackground/aims: Regulatory T cells (Tregs) play key roles in maintaining peripheral tolerance and preventing autoimmune disease. Treg modulation could be helpful in treating malignancies, autoimmune disease, and allergies, as well as to facilitate organ transplantation. Signals transduced by co-stimulatory molecules are essential for Treg differentiation, homeostasis, and function.
View Article and Find Full Text PDFA facile synthetic route towards pharmaceutically interesting β-keto-sulfone derivatives by tetrabutylammonium iodide (TBAI)/tert-butyl hydroperoxide (TBHP) mediated oxidative coupling of readily prepared enamides with economical sulfonylhydrazides is described. The corresponding β-keto-sulfone compounds were obtained in moderate to good yields. The present method is metal-free and base-free and shows tolerance to a variety of functional groups.
View Article and Find Full Text PDFB cells play an important role in the clearance of hepatitis B virus (HBV) and protection against reinfection. However, the functional characteristics of these cells that are associated with the outcome of chronic HBV infection remain unknown. We comprehensively investigated the frequency, phenotype, and function of peripheral B-cell subsets from CHB patients in different phases: immune tolerance (IT), immune activation (IA), immune clearance (IC), responders with HBsAg seroconversion (resolved patients, RP), and healthy controls (HC).
View Article and Find Full Text PDFAn efficient metal-free oxidative arylsulfonylation of α,β-unsaturated imides with sulfonylhydrazides leading to isoquinoline-1,3(2H,4H)-dione derivatives has been developed. The procedure involves the generation of sulfonyl radicals via cleavage of the S-N bond of sulfonylhydrazides with sulfonylation and C-H functionalization. The protocol uses the economical and environmentally friendly TBAI-TBHP catalytic system, and the corresponding isoquinoline-1,3(2H,4H)-diones with various functional groups were obtained in moderate to good yields.
View Article and Find Full Text PDFObjective: To explore the expression of CD160, a costimulator, on CD4(+) and CD8(+) T cells in chronic human immunodeficiency virus-1 (HIV-1) infected patients.
Methods: A total of 23 chronic HIV-1 infected patients were enrolled into 302 Hospital of People's Liberation Army from January 2010 to December 2011. Meanwhile, 20 healthy individuals were selected as healthy controls (HC).
Unlabelled: There is increasing interest in the role of T follicular helper (Tfh) cells in autoimmunity from the perspective of both their role in breach of tolerance and their effects on the natural history of disease progression. Indeed, the critical role of Tfh cells in autoimmunity is further highlighted based on their location in the germinal center (GC), a pathogenic hot spot for development of autoreactivity. To address the role of Tfh cells in primary biliary cirrhosis (PBC), we comprehensively evaluated the immunobiology of CXCR5(+) CD4(+) Tfh cells in 69 patients with PBC, including a nested subgroup of 16 autoimmune hepatitis (AIH) and 20 healthy controls (HC), followed for 1 year.
View Article and Find Full Text PDFRadiation therapy (RT) is an integral component of the treatment of many sarcomas and relies on accurate targeting of tumor tissue. Despite conventional treatment planning and RT, local failure rates of 10% to 28% at 5 years have been reported for locally advanced, unresectable sarcomas, due in part to limitations in the cumulative RT dose that may be safely delivered. We describe studies of the potential usefulness of gold nanoparticles modified for durable systemic circulation (through polyethylene glycosylation; hereinafter "P-GNPs") as adjuvants for RT of sarcomas.
View Article and Find Full Text PDFA novel arylalkoxycarbonylation of N-aryl acrylamides with carbazates leading to alkoxycarbonylated oxindoles has been developed. The reported reactions employ economical and environmentally benign FeCl2·4H2O as a catalyst and easily accessible and safe carbazates as alkoxycarbonyl radical precursors.
View Article and Find Full Text PDFInterleukin-21 (IL-21)+CD4+ T cells are involved in the immune response against hepatitis B virus (HBV) by secreting IL-21. However, the role of IL-21+CD4+ T cells in the immune response against chronic hepatitis C (CHC) virus infection is poorly understood. This study aimed to investigate the role of IL-21+CD4+ T cells in CHC patients and the potential mechanisms.
View Article and Find Full Text PDFHalosulfonylation of terminal alkynes was achieved with sulfonylhydrazides as the sulfonyl precursor and inexpensive iron halide as halide source in the presence of TBHP, allowing the regio- and stereoselective generation of (E)-β-chloro and bromo vinylsulfones.
View Article and Find Full Text PDFObjective: HAART largely decreases morbidity and mortality in chronic HIV-1-infected patients, but immune nonresponders (INRs) with full viral suppression still fail to reverse the immune deficiency. This study evaluated the safety and immunological responses of human umbilical cord mesenchymal stem cell (MSC) therapy in HIV-1-infected INRs.
Design And Methods: A total of 13 HIV-1-infected INRs were enrolled in this pilot prospectively open-labeled controlled clinical trial.
Aim: Interleukin-21 (IL-21) is involved in effective primary hepatic immune response against hepatitis B virus (HBV) and profibrotic function. However, the role of IL-21 in HBV-associated liver cirrhosis is poorly understood. This study aimed to investigate the role of IL-21 in HBV-associated liver cirrhosis and possible mechanisms.
View Article and Find Full Text PDFA catalytic system consisting of KI, 18-crown-6, and TBHP for arylsulfonylation of activated alkenes with sulfonylhydrazides as sulfonyl precursor is described. This protocol provides a practical and environmentally benign method for the construction of sulfonated oxindoles in water.
View Article and Find Full Text PDFIntroduction. PET imaging is a useful clinical tool for studying tumor progression and treatment effects. Conventional (18)F-FDG-PET imaging is of limited usefulness for imaging Glioblastoma Multiforme (GBM) due to high levels of glucose uptake by normal brain and the resultant signal-to-noise intensity.
View Article and Find Full Text PDFDysfunctional hepatitis C virus (HCV) specific CD4(+) T cells are known to contribute to inadequate adaptive immunity in chronic hepatitis C (CHC), although the underlying mechanisms remain largely undefined. In this study, OX40 ligand (OX40L) expression was investigated in 41 treatment-naïve CHC patients, 20 sustained virological responders and 36 healthy subjects. We observed that OX40L expression was significantly upregulated in peripheral monocytes in CHC patients compared with sustained virological responders and healthy subjects.
View Article and Find Full Text PDFA tetrabutylammonium iodide catalyzed method for the synthesis of allyl aryl sulfone derivatives with Baylis-Hillman acetates and sulfonylhydrazides using tert-butyl hydroperoxide as an oxidation agent in water has been developed. In this process, the group eliminated from the sulfonyl precursor is molecular nitrogen.
View Article and Find Full Text PDFGlioblastoma multiforme (GBM) is a common, usually lethal disease with a median survival of only ~15 months. It has proven resistant in clinical trials to chemotherapeutic agents such as paclitaxel that are highly effective in vitro, presumably because of impaired drug delivery across the tumor's blood-brain barrier (BBB). In an effort to increase paclitaxel delivery across the tumor BBB, we linked the drug to a novel filomicelle nanocarrier made with biodegradable poly(ethylene-glycol)-block-poly(ε-caprolactone-r-D,L-lactide) and used precisely collimated radiation therapy (RT) to disrupt the tumor BBB's permeability in an orthotopic mouse model of GBM.
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