Publications by authors named "Xue-Shi Huang"

Thirty-six structurally diverse sesquiterpenoids, including caryolanes (1-12), germacranes (13-16), isodaucane (17), cadinanes (18-22), epicubenols (23, 24), oplopanane (25), pallenanes (26, 27), and eudesmanes (28-36), were isolated from the fermentation broth of Streptomyces fulvorobeus derived from Elephas maximus feces. Pallenane is a kind of rarely reported sesquiterpene with a distinctive C5/C3 bicyclic skeleton and was firstly found from microbial source. The structures of fifteen new compounds (1-4, 13-15, 17, 18, 22, 23, 25-28) were established through detailed spectroscopic data analysis, which included data from experimental and calculated ECD spectra as well as Mosher's reagent derivative method.

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Researchers continue to explore drug targets to treat the characteristic pathologies of Alzheimer's disease (AD). Some drugs relieve the pathological processes of AD to some extent, but the failed clinical trials indicate that multifunctional agents seem more likely to achieve the therapy goals for this neurodegenerative disease. Herein, a novel compound named melatonin-trientine (TM) has been covalently synthesized with the natural antioxidant compounds melatonin and the metal ion chelator trientine.

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Background: Neuroinflammation is thought to be a cause of Alzheimer's disease (AD), which is partly caused by inadequate mitophagy. As a receptor of mitophagy, we aimed to reveal the regulatory roles of optineurin (OPTN) on neuroinflammation in the pathogenesis of AD.

Methods: BV2 cells and APP/PS1 transgenic (Tg) mice were used as in vitro and in vivo experimental models to determine the regulatory roles of OPTN in neuroinflammation of AD.

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ABATRACTNine compounds, five phenolic glycosides (, , ), three phenylpropanoids (), and a furanone glycoside (), were isolated from aqueous soluble extract of the dried roots of Bunge. The structures of new compounds () were elucidated by comprehensive spectroscopic data analysis as well as chemical evidence. Pulsatillanin A () demonstrated significant antioxidant effects through scavenging free radical in DPPH assay, and relieved the oxidative stress in LPS-induced RAW 264.

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A yellow, Gram-stain-negative, aerobic, non-gliding, non-spore-forming, rod-shaped strain, designated YIM 102600, was isolated from the faeces of dwelling in the Yunnan Wild Animal Park, Yunnan Province, South-West PR China. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain YIM 102600 was a member of the genus , and closely related to F3 (96.9 % similarity) and R-HLS-17 (96.

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Three new phenazine metabolites, strepphenazine A-C (), along with a known compound baraphenazine E were isolated from the culture broth of a strain YIM PH20095. The structures were elucidated based on the spectral data. Compounds showed different antifungal activity against , , , and , which caused root-rot disease of with minimal inhibitory concentrations (MICs) of 16-64 μg/mL; compared with compound , compounds showed better antifungal activity against some of these pathogenic fungi with MICs of 16-32 μg/mL, while compound showed antifungal activity against , , and with the same MICs of 64 μg/mL.

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Background: Recent studies have revealed that vitamin D deficiency may increase the risk of Alzheimer's disease, and vitamin D supplementation may be effective strategy to ameliorate the neurodegenerative process in Alzheimer's disease patients. Paricalcitol (PAL), a low-calcemic vitamin D receptor agonist, is clinically used to treat secondary hyperparathyroidism. However, the potential application of PAL for treating neurodegenerative disorders remains unexplored.

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Alzheimer's disease (AD) is reportedly associated with the accumulation of calcium ions (Ca), and this accumulation is responsible for the phosphorylation of tau. Although several lines of evidence demonstrate the above phenomenon, the inherent mechanisms remain unknown. Using APP/PS1 Tg mice and neuroblastoma (N)2a cells as and experimental models, we observed that Ca stimulated the phosphorylation of tau by activating microsomal PGE synthase 1 (mPGES1) in a prostaglandin (PG) E-dependent EP receptor-activating manner.

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Alzheimer's disease (AD) is reported to be associated with the accumulation of calcium ions (Ca2+), which is responsible for the phosphorylation of tau. Although a series of evidence have demonstrated this phenomenon, the inherent mechanisms remain unknown. Using tauP301S and cyclooxygenase-2 (COX-2) transgenic mice and neuroblastoma (n)2a cells as in vivo and in vitro experimental models, we found that Ca2+ stimulates the phosphorylation of tau by activating COX-2 in a prostaglandin (PG) E2-dependent EP receptor-activating manner.

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Huge numbers of bacteria reside in the digestive tract of host and these microorganisms play a vital role in the host health, especially in the digestion of food and the development of immune system. Host phylogeny and diet, especially long-term diet, both have great influence on the gut bacterial community. Other aspects of host, such as gender, age, and the geography and weather they lived, are also correlated to their gut bacterial community.

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Five new compounds including five iridoids (1-5) and six known compounds were isolated from the rhizomes of Scrophularia ningpoensis. Their structures were determined by extensive NMR and IR, MS spectroscopic data analyses. The anti-inflammatory, antibacterial, antifungal, and cytotoxic activities of the isolated compounds were evaluated.

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Alzheimer's disease (AD) is characterized by the loss of neurogenesis and excessive induction of apoptosis. The induction of neurogenesis and inhibition of apoptosis may be a promising therapeutic approach to combating the disease. Celecoxib (CB), a cyclooxygenase-2 specific inhibitor, could offer neuroprotection.

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A novel actinobacterium, designated YIM 101593T, was isolated from the faeces of a primate (Rhinopithecus roxellanae) living in Yunnan Wild Animal Park in Yunnan province, south-west China. The isolate was Gram-stain-positive, facultatively anaerobic, coccus-shaped, oxidase-negative and motile. The cell wall contained meso-diaminopimelic acid as its diagnostic diamino acid, and mannose, ribose, glucose, galactose and arabinose were detected as the main whole-cell sugars.

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A novel strain, YIM 100770, was isolated from Rhinoceros unicornis faeces collected from Yunnan Wild Animal Park, China. The taxonomic status was determined based on the physiological, biochemical and phylogenetic characteristics. Strain YIM 100770 was observed to be rod-shaped, non-motile, Gram-stain negative and aerobic.

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A novel, yellow, aerobic strain, YIM 101168T, isolated from the faeces of a dove (Columba livia), was studied to determine its taxonomic position. Cells were Gram-stain-positive, short rod-shaped, oxidase-negative, catalase-positive and non-motile. The strain could grow at 7-37 °C, at pH 6-10 and in the presence of 0-13 % (w/v) NaCl.

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A novel aerobic, non-motile, Gram-positive, rod-shaped actinobacterium, designated YIM 100951(T), was isolated from the faeces of civets (Viverra zibetha) living in the National Nature Protect Region in Selangor, Malaysia. Strain YIM 100951(T) shows high similarities with Microbacterium barkeri DSM 20145(T) (97.6 %), Microbacterium oryzae MB10(T) (97.

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A Gram-stain-positive, facultatively anaerobic, short rod-shaped, oxidase-negative and non-motile novel strain, designated YIM 101505T, was isolated from the faeces of a primate, Assamese macaque, and was studied to determine its taxonomic position. The cell wall contained meso-diaminopimelic acid and short-chain mycolic acids. Whole cell sugars were mannose, galactose and arabinose as major components.

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Two novel actinobacteria, designated strains YIM 101617(T) and YIM 101632(T), were isolated from Lama pacos (alpaca) and Viverra zibetha (civet) faeces in Yunnan Wild Animal Park in Yunnan province, southwestern China. Both strains should be placed in genus Enteractinococcus based on phylogenetic analysis. Based on 16S rRNA gene sequence analysis, strain YIM 101617(T) exhibits high similarity to Enteractinococcus fodinae DSM 22966(T) (97.

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Four new prenylindole derivatives, (R)-6-(2,3-dihydroxy-3-methylbutyl)indole (1), (R)-6-(2,3-dihydroxy-3-methylbutyl)indolin-2-one (2), and an unseparated mixture of (Z)-6-(4-hydroxy-3-methylbut-2-en-1-yl)indolin-2-one (3a) and (E)-6-(4-hydroxy-3-methylbut-2-en-1-yl)indolin-2-one (3b) with a ratio of 3 : 2, were isolated from the culture broth of a streptomycete isolated from Ailuropoda melanoleuca feces. Their structures were elucidated on the basis of 1D and 2D NMR spectroscopic techniques. The absolute configuration of 1 was determined by Mosher's method.

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Prior work has shown that iron interacts with hyperphosphorylated tau, which contributes to the formation of neurofibrillary tangles (NFTs) in Alzheimer's disease (AD), whereas iron chelator desferrioxamine (DFO) slows down the clinical progression of the cognitive decline associated with this disease. However, the effects of DFO on tau phosphorylation in the presence or absence of iron have yet to be determined. Using amyloid precursor protein (APP) and presenilin 1 (PS1) double transgenic mouse brain as a model system, we investigated the effects and potential mechanisms of intranasal administration of DFO on iron induced abnormal tau phosphorylation.

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A novel actinobacterium, designated strain YIM 100590(T), was isolated from Panthera tigris amoyensis faeces collected from Yunnan Wild Animal Park in Yunnan province, south-west China. Phylogenetic analysis based on 16S rRNA gene sequence data showed that strain YIM 100590(T) is a member of the family Micrococcaceae. Cells were coccoid to oval (0.

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Gilvocarcin-type polyketide glycosides represent some of the most powerful antitumor therapeutics. Bioactivity-guided fractionation of a culture extract of Streptomyces polyformus sp. nov.

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This paper describes natural products, semi-synthetic natural products and natural product-derived compounds used for treating antiparasitic, antiviral and neurological disease that were being evaluated in clinical trials or in registration from 1998 to the end of 2005.

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Natural products have played an important role in drug discovery. Today, therapeutics from natural origin count for about 70% of the worldwide human therapeutic sales. For anti-infective treatment even higher figures are reported.

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The mass spectrometric behavior of phenanthroindolizidine alkaloids has been investigated in detail by positive ion fast atom bombardment tandem mass spectrometry (FAB-MS/MS) combined with collision-induced dissociation (CID). The fragmentation has been correlated with the skeleton structure and positions of substituents. The product ions arising from retro-Diels-Alder cleavages differ clearly for compounds with different skeletons.

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