Activation of nuclear factor erythroid 2-related factor 2 (Nrf2) by Kelch-like ECH-associated protein 1 (Keap1) alkylation plays a central role in anti-inflammatory therapy. However, activators of Nrf2 through alkylation of Keap1-Kelch domain have not been identified. Deoxynyboquinone (DNQ) is a natural small molecule discovered from marine actinomycetes.
View Article and Find Full Text PDFProtein-biomolecule interactions play pivotal roles in almost all biological processes. For a biomolecule of interest, the identification of the interacting protein(s) is essential. For this need, although many assays are available, highly robust and reliable methods are always desired.
View Article and Find Full Text PDFPurpose: This study aimed to investigate the effect of exercise intervention, and analyze exercise intervention strategies for adolescent depression through a meta-analysis of RCTs.
Methods: Accordance to PRISMA guidelines, PubMed, Medline, EBSCO, Web of Science, SPORTDiscus, PsycINFO, ProQuest, and CNKI were searched for eligible records. Peer-reviewed studies were included if they met the following criteria: population (mean age of 10-18 years), intervention (physical activity, sport, or exercise), and outcomes (depression, adherence, ITT, dropout, adverse events, follow-up report).
A novel classical kinetic resolution of 2-aryl-substituted or 2,3-disubstituted cyclobutanones of Baeyer-Villiger oxidation catalyzed by a Cu(ii)/SPDO complex is reported for the first time, producing normal lactones in excellent enantioselectivities (up to 96% ee) and regioselectivities (up to >20/1), along with unreacted ketones in excellent enantioselectivities (up to 99% ee). The current transformation features a wide substrate scope. Moreover, catalytic asymmetric total syntheses of natural eupomatilones 5 and 6 are achieved in nine steps from commercially available 3-methylcyclobutan-1-one.
View Article and Find Full Text PDFAlthough copper-nitrene has been extensively studied as a versatile active species in various transformations, asymmetric reactions involving copper-nitrene have been limited to the aziridination of olefins. Herein, we report the novel copper-nitrene-catalyzed desymmetric oxaziridination reaction of cyclic diketones with alkyl azides and the subsequent rearrangement of the resulting highly active intermediate, which produces a synthetically challenging chiral bicyclic lactam containing a quaternary carbon center. This procedure not only enriches the copper-nitrene-catalyzed asymmetric reactions, but also provides an alternative strategy to address the inherent challenges of catalytic asymmetric Schmidt reactions.
View Article and Find Full Text PDFPropofol is a widely used intravenous anesthetic agent in sedation and general anesthesia. To improve the safety and maintain the depth of anesthesia, it is important to develop a rapid, sensitive, and reliable method to monitor the concentration of propofol in blood during anesthesia continuously. Here, we present a novel strategy based on paper spray ionization-mass spectrometry (PSI-MS) to detect propofol.
View Article and Find Full Text PDFThe catalytic asymmetric total syntheses of the biologically important and therapeutically valuable alkaloids (-)-galanthamine and (-)-lycoramine have been divergently achieved from commercially available 3-butyn-1-ol. A newly developed spirocyclic pyrrolidine (SPD)-catalyzed enantioselective Robinson annulation rapidly constructs the key -hydrodibenzofuran core, which bears an all-carbon quaternary stereocenter of the target molecules with an excellent stereoselective control. Additionally, the current asymmetric synthetic strategy provides an alternative approach toward the syntheses of (-)-galanthamine and its analogues.
View Article and Find Full Text PDF(‒)-Morphine, which is selected as an essential medicine by World Health Organization, is widely applied in the treatment of the pain-related diseases. Due to its synthetically challenging molecular architecture and important clinical role, extensive synthetic studies of morphine-type alkaloids have been conducted. However, catalytic asymmetric total synthesis of (‒)-morphine remains a long-standing challenge.
View Article and Find Full Text PDFYing Yong Sheng Tai Xue Bao
November 2012
A pot experiment was conducted to study the variations of the photo-physiological characteristics of native bluestem (Bothriochloa ischaemum) in loess hilly-gully region under different soil moisture condition (80% and 40% field capacity) and different atmospheric CO2 concentration (375 micromol x m(-2) x s(-1) and 750 micromol x m(-2) x s(-1). The results showed that drought stress decreased the maximum photosynthetic rate (Pn max), apparent quantum efficiency (AQE), stomatal conductance (ga), transpiration rate (Tx), maximum photochemical efficiency (F/Fm), potential photochemical efficiency (Fv/Fo), and photosynthetic pigments contents, and increased the malondialdehyde (MDA) and proline (Pro) contents. Under sufficient moisture condition, elevated CO2 concentration didn't change the P n max and the, MDA and Pro contents significantly; under drought stress, elevated CO2 improved the maximal fluorescence (Fm), Fv/Fm, Fv/Fo, photosynthetic pigments contents, and AQE, and the Pn max under elevated CO2 was increased significantly by 23.
View Article and Find Full Text PDFTo explore the rhizosphere effect of the microelements in the soils under different vegetation types in Loess Plateau, this paper analyzed the organic C, total N, Mn, Cu, Fe, and Zn contents in the rhizosphere soil and bulk soil of six vegetation types in hilly-gully region of Loess Plateau. Among the six vegetation types, Caragana korshinskii, Heteropappus altaicus, and Artemisia capillaries had higher organic C and total N contents in rhizosphere soil than in bulk soil. With the exception of C.
View Article and Find Full Text PDFA novel aerobic actinomycete strain, designated as SCSIO 02100(T), was isolated from a deep sea sediment sample collected from Northern South China Sea at a depth of 578 m. This isolate requires sea water or a sodium-supplemented medium for growth. BLAST searches based on the almost full length of the 16S rRNA gene sequence, showed that strain SCSIO 02100(T) had the highest similarities with Streptomyces armeniacus (JCM 3070(T)) (97.
View Article and Find Full Text PDFAn aerobic actinomycete, designated SCSIO 01299(T), was isolated from a deep-sea sediment collected from the northern South China Sea at a depth of 3258 m. The isolate was found to be a natural producer of the synthesized antitumour agent deoxynyboquinone and its three new derivatives, pseudonocardians A, B and C. A blast search based on almost-complete 16S rRNA gene sequences showed that strain SCSIO 01299(T) had high sequence similarities with members of the genus Pseudonocardia.
View Article and Find Full Text PDFA novel filamentous bacterium, strain SCSIO 10219(T), was isolated from a sediment sample collected from the South China Sea (113° 3.752' E 18° 1.722' N) at a depth of 2105 m.
View Article and Find Full Text PDFInt J Syst Evol Microbiol
April 2012
A novel aerobic streptomycete, strain SCSIO 01248T, was isolated from a sample of deep-sea sediment collected from the northern South China Sea, at a depth of 1632 m. This isolate formed yellow-white substrate mycelium and grey-white aerial hyphae. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain SCSIO 01248T was most closely related to Streptomyces radiopugnans R97T (98.
View Article and Find Full Text PDFA systematic phytochemical examination of the whole plant Dracocephalum forrestii led to the isolation of 4 new and 65 known chemical constituents. By detailed 1D and 2D NMR spectroscopic analyses, the new compounds were identified as 4-hydroxy-3-methoxyphenylethanol 8- O-[(6- O-syringoyl)- beta- D-glucopyranoside] (1), 3,4,5-trimethoxyphenylethanol beta- D-glucopyranoside ( 2), 4- O-[ beta- D-glucopyranosyl-(1 --> 3)- alpha- L-rhamnopyranosyl]phenylethylcinnamamide (3), and 9''- O- N-butyl lithospermate (4). The new isolates were evaluated for inhibitory activities against LPS-induced NO production in RAW 264.
View Article and Find Full Text PDFWheat hybrid necrosis has been genetically characterised for many years, but the specific gene(s) and the protein products involved in the processes remains unknown. In this study, protein expression in the base (B), mid (M) and tip (T) segments of the FL-2 leaves of a necrotic hybrid, PZF1 and its parents, Pan555 and Zheng891, was analysed and compared using a high throughput proteomic approach. Twenty-three protein spots, with significant variations in intensity across the necrotic leaf segments, were analysed by MALDI-TOF-MS, of which, 18 were matched to protein accessions in the NCBI database.
View Article and Find Full Text PDFGuang Pu Xue Yu Guang Pu Fen Xi
December 2002
In the biosynthesis of the C7-cyclitol moiety, valienol, of the alpha-glucosidase inhibitor acarbose in Actinoplanes sp. SE50/110 various cyclitol phosphates, such as 1-epi-valienol-7-phosphate, are postulated precursors. In the cell extracts of Actinoplanes SE50/110 we found a new kinase activity which specifically phosphorylates 1-epi-valienol; other C7-cyclitol analogs were only weakly or not phosphorylated.
View Article and Find Full Text PDFThe C7-cyclitol 2-epi-5-epi-valiolone is the first precursor of the cyclitol moiety of the alpha-glucosidase inhibitor acarbose in Actinoplanes sp. SE50. The 2-epi-5-epi-valiolone becomes phosphorylated at C7 by the ATP dependent kinase AcbM prior to the next modifications.
View Article and Find Full Text PDFWe have previously demonstrated that the biosynthesis of the C(7)-cyclitol, called valienol (or valienamine), of the alpha-glucosidase inhibitor acarbose starts from the cyclization of sedo-heptulose 7-phosphate to 2-epi-5-epi-valiolone (Stratmann, A., Mahmud, T., Lee, S.
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