Publications by authors named "Guang Shen"

This work aimed to investigate the effects of frozen storage on volatile compounds of white meats (chicken and duck) and red meats (pork, beef, and mutton). The samples were stored at -18 °C for 0, 2, 4, 10, 18 weeks, and volatile compounds were analyzed by headspace solid-phase microextraction coupled with gas chromatography-mass spectrometry. Results indicated that the total amounts of volatile compounds increased with frozen storage duration of meats.

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This study investigated the effects of piperine on oxidation-induced porcine myofibrillar protein (MP) gelation behavior and fluorescent advanced glycation end products (fAGEs) formation. Model systems were prepared, lipid oxidation, MP gelling behavior, and fAGEs content were determined daily. The results indicated that lipid oxidation, carbonyl content, S, cooking loss, and tryptophan fluorescence intensity of MP significantly decreased, whereas gel strength, WHC, and whiteness markedly increased as the concentration of piperine increased (from 0 to 30 μM/g protein), indicating that piperine could reduce lipid oxidation and oxidative damage to MP.

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Lingonberry (Vaccinium vitis-idaea L.) extract contains various active ingredients with strong inhibitory effects on cancer cell growth. HepG2 cells were treated with various concentrations of lingonberry extract, cell inhibition rate was measured by CCK-8 assay, and apoptosis rate by annexin-propidium iodide double-staining assay.

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The roots of Rodin (TKS) are well-known and valued for their rubber-producing ability. Therefore, research on the analysis and detection of metabolites from the roots of TKS have been reported in previous studies. However, all of these studies have the shortcoming of focusing on only the rubber of TKS, without profiling the other metabolites in a systematic and comprehensive way.

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The synthesis of five series of 4'-truncated nucleoside phosphonic acid analogues is discussed in this review: (1) 4'-truncated furanose nucleoside phosphonic acid analogues; (2) 4'-truncated pyrrolidine nucleoside phosphonic acid analogues; (3) 4'-truncated carbocyclic nucleoside phosphonic acid analogues; (4) 4'-truncated isoxazole nucleoside phosphonic acid analogues; (5) 4'-truncated miscellaneous nucleoside phosphonic acid analogues. Five different ways are used to make the phosphonate moiety: (i) Michaelis-Arbuzov reaction of RX (X = Br, I, OTf) with trialkyl phosphate; (ii) Lewis acid catalyzed Michaelis-Arbuzov reaction of glycoside with trialkyl phosphite; (iii) nucleophilic addition of a dialkyl phosphite to a carbonyl group; (iv) direct coupling reaction with amino alkyl phosphonate; (v) de novo synthesis of phosphonated-isoxazole and 1,3-dioxolane heterocycles from phosphonated starting materials. Their biological activity results are briefly discussed.

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The present review focuses on the synthesis of cyclic 5'-deoxynucleoside phosphonate analogs. The formation of various phosphonate alkyl moieties is accomplished through (i) Wittig (or HWE) type condensation to the nucleoside aldehyde moiety; (ii) nucleophilic displacement reaction using phosphonate anion or Lewis acid; (iii) Arbuzov reaction; (iv) olefin cross-metathesis between vinyl phosphonates and vinylated nucleosides; and (v) radical reaction and Pd catalyzed alkyne. For the coupling of nucleobases with cyclic moieties, the Mitsunobu reaction and Sonogashira-type cross-coupling are usually applied.

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The striped flea beetle, Phyllotreta striolata (Fabricius), damages crops in the Brassicaceae. The genetic data for this pest are insufficient to reveal its insecticide resistance mechanisms or to develop molecular markers for resistance monitoring. We used PacBio Iso-Seq technology to sequence the full-length transcriptome of P.

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The syntheses of acyclic nucleoside phosphonate (ANP) analogs linked with cyclic systems are described in the present review. The purpose of the review is to report the methodology of ANP analogs and to give an idea on the synthesis of a therapeutic structural feature of such analogs. The cyclopropane systems were mainly prepared by diazomethane cyclopropanation catalyzed by Pd(OAc)2, intramolecular alkylation, Kulinkovich cyclopropanation, and use of difluorocyclopropane, and so forth.

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Background: Recent studies have shown that microRNAs (miRNAs) are involved in the process of cardiomyocyte apoptosis. We have previously reported that granulocyte-colony stimulating factor (G-CSF) ameliorated diastolic dysfunction and attenuated cardiomyocyte apoptosis in a rat model of diabetic cardiomyopathy. In this study, we hypothesized a regulatory role of cardiac miRNAs in the mechanism of the anti-apoptotic effect of G-CSF in a diabetic cardiomyopathy rat model.

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Objective: Positive symptoms, such as delusion and hallucination, commonly include negative emotional content in schizophrenia. We investigated the neural basis implicated during the processing of strong negative emotional words in patients with schizophrenia.

Methods: In our study, 35 patients with schizophrenia and 19 healthy controls were recruited, and the participants were asked to passively view the words that contained swearing and neutral content during functional magnetic resonance imaging.

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The residues and risks of heavy metals in the environment and organisms have attracted great concern for many years. However, the information on their long-term spatiotemporal trends and potential health and ecological risks are scarce. In this study, a total of 1815 seawater samples, 451 sediment samples, and 54 seafood samples were collected in Xiangshan Bay, China, between 2011 and 2016.

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Nucleoside phosphonates are isosteric, isopolar, and isoelectronic with phosphates. Nucleoside phosphonates can undergo enzymatic phosphorylation for conversion into the corresponding diphosphoryl phosphonates, which are naturally occurring nucleoside triphosphate analogues. The biological activity, which is mostly antiviral and antitumor but sometimes is as specific enzyme inhibitor, is briefly presented to help discover compounds with increased activity over natural nucleosides to provide structure-activity data.

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Background And Objectives: Whether cigarette smoking can increase the risk of hip fracture in women is unclear. This meta-analysis, which pooled results from 10 prospective cohort studies, was performed to derive a more precise estimation between cigarette smoking and the risk of hip fracture in women.

Materials And Methods: Pubmed, Cochrane Central Register of Controlled Trials and ISI Web of Science were systematically searched to identify relevant studies.

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Iron accumulation is a risk factor of osteoporosis; mechanisms leading to iron-related bone loss are not fully determined. We sought to better understand the effect of chronic iron accumulation on bone over the life span in a mouse model. Hepcidin1 knockout (Hepc1(-/-)) male mice and their littermate control wild type (WT) mice at 7 months old were used in this study.

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A very efficient synthetic route to novel 2',2'-difluoro 5'-norcarbocyclic phosphonic acid nucleosides from but-3-en-1-ol 5 is described. The discovery of 2'-fluorinated furanose nucleoside 1 as a potent anti-HIV-1 agent has led to the synthesis and biological evaluation of 2'-modified 5'-norversions of the carbocyclic phosphonate nucleosides. The synthesized nucleoside analogues 18, 19, 23a, 23b, and 24 were tested for anti-HIV activity as well as cytotoxicity.

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The authors describe highly efficient synthetic routes for the preparation of novel 6',6'-difluoro 5'-deoxycarbocyclic phosphonic acid nucleosides from 1,4-dihydroxy-2-butene. The discovery that the 6'-fluorinated carbocyclic nucleoside (2, EC₅₀ = 0.16 μM) is a potent anti-HSV-1 agent led to the syntheses and biological evaluations of 6'-modified 5'-deoxyversions of carbocyclic phosphonate nucleosides.

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A very efficient synthetic route to novel 3'-hydroxymethyl 5'-deoxythreosyl phosphonic acid nucleosides was described. The discovery of threosyl phosphonate nucleoside (PMDTA, EC(50) = 2.53 μM) as a potent antihuman immunodeficiency virus (anti-HIV) agent has led to the synthesis and biological evaluation of 3'-modified 5'-deoxy versions of the threosyl phosphonate nucleosides.

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Novel 5'-deoxyfuranosyl purine phosphonic acid analogues with 2 '-electropositive moiety, such as spirocyclopropanoid, were designed and synthesized from commercially available diethyl malonate. Condensation reaction successfully proceeded from a glycosyl donor 15 at low reaction temperature in Vorbruggen conditions to give desired phosphonate analogues 16b and 23b. The synthesized nucleotide analogues 19, 22, 26, and 29 were subjected to antiviral screening against HIV-1.

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Novel 5'-norcarbocyclic adenine and guanine phosphonic acid analogues with 6',6'-difluorine moiety were designed and synthesized from commercially available epichlorohydrin 5. A regioselective Mitsunobu reaction successfully proceeded from an allylic functional group 16b at low reaction temperature in polar cosolvent to give purine phosphonate analogues 17 and 24, respectively. The purine nucleoside phosphonate and phosphonic acid analogues were subjected to antiviral screening against HIV-1.

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Novel 4'-cyclopropyl-5'-norcarbocyclic adenosine phosphonic acid analogues were designed and racemically synthesized from propionaldehyde 5 through a de novo acyclic stereoselective route using triple Grignard addition and ring-closing metathesis (RCM) as key reactions. To improve cellular permeability and enhance the anti-HIV activity of this phosphonic acid, SATE phosphonodiester nucleoside prodrug 23 was prepared. The synthesized adenosine phosphonic acids analogues 17, 18, 19, 21, and 23 were subjected to antiviral screening against HIV-1.

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