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result(s) for
"Yan, Qing-Xiang"
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Citriquinolinones A and B: Rare Isoquinolinone-Embedded Citrinin Analogues and Related Metabolites from the Deep-Sea-Derived Aspergillus versicolor 170217
by
Liu, Guang-Ming
,
Yang, Xian-Wen
,
Jiang, Jia-Yang
in
anti-food allergic activity
,
Aspergillus versicolor
,
Bridges
2023
A systematic chemical investigation of the deep-sea-derived fungus Aspergillus versicolor 170217 resulted in the isolation of six new (1–6) and 45 known (7–51) compounds. The structures of the new compounds were established on the basis of exhaustive analysis of their spectroscopic data and theoretical–statistical approaches including GIAO-NMR, TDDFT-ECD/ORD calculations, DP4+ probability analysis, and biogenetic consideration. Citriquinolinones A (1) and B (2) feature a unique isoquinolinone-embedded citrinin scaffold, representing the first exemplars of a citrinin–isoquinolinone hybrid. Dicitrinones K–L (3–4) are two new dimeric citrinin analogues with a rare CH-CH3 bridge. Biologically, frangula-emodin (32) and diorcinol (17) displayed remarkable anti-food allergic activity with IC50 values of 7.9 ± 3.0 μM and 13.4 ± 1.2 μM, respectively, while diorcinol (17) and penicitrinol A (20) exhibited weak inhibitory activity against Vibrio parahemolyticus, with MIC values ranging from 128 to 256 μM.
Journal Article
Total Synthesis and Anti-Inflammatory Bioactivity of (−)-Majusculoic Acid and Its Derivatives
by
Yang, Xian-Wen
,
He, Zhi-Hui
,
Yan, Qing-Xiang
in
(−)-majusculoic acid
,
Analogs
,
anti-inflammation
2021
The first total synthesis of marine natural product, (−)-majusculoic acid (1) and its seven analogs (9–15), was accomplished in three to ten steps with a yield of 3% to 28%. The strategy featured the application of the conformational controlled establishment of the trans-cyclopropane and stereochemical controlled bromo-olefination or olefination by Horner–Wadsworth–Emmons (HWE) reaction. The potential anti-inflammatory activity of the eight compounds (1 and 9–15) was evaluated by determining the nitric oxide (NO) production in the lipopolysaccharide (LPS)-induced mouse macrophages RAW264.7. (−)-Majusculoic acid (1), methyl majusculoate (9), and (1R,2R)-2-((3E,5Z)-6-bromonona-3,5-dien-1-yl)cyclopropane-1-carboxylic acid (12) showed significant effect with inhibition rates of 33.68%, 35.75%, and 43.01%, respectively. Moreover, they did not show cytotoxicity against RAW264.7 cells, indicating that they might be potential anti-inflammatory agents.
Journal Article
Quantitative Trait Locus Analysis for Yield Traits of Cassava (Manihot esculenta Crantz)
2014
The QTLs associated with cassava yield traits were detected by two-QTL model (unconditional and conditional QTLs) approaches after planting for 90 d, 180 d and 270 d in the present study. A genetic linkage map was constructed with a segregating F1 population derived from a cross of 2 heterozygous parental plants from the cultivars South China 6 and Mianbao, and analysed with 39 SSR markers. The constructed linkage map of cassava consisted of 12 linkage groups covering a total length of 694.59 cM with a mean distance of 17.81 cM between two markers. The F1 population was evaluated for components of yield including fresh root yield (FRY), harvest index (HI), and starch content in dry root weight (SC) at 90 d, 180 d and 270 d. The identification of QTLs for yield traits at three growth periods explained 56.4% for FRY, 16.3% for HI and 27.3% for SC, suggesting characterization of yield components. The work made a step closer to understand the persistence of quantitative genetic variations of cassava in different development periods.
Journal Article
Citriquinolinones A and B: Rare Isoquinolinone-Embedded Citrinin Analogues and Related Metabolites from the Deep-Sea-Derived IAspergillus versicolor/I 170217
by
Liu, Guang-Ming
,
Yang, Xian-Wen
,
Jiang, Jia-Yang
in
Antibacterial agents
,
Aspergillus
,
Chemical properties
2023
A systematic chemical investigation of the deep-sea-derived fungus Aspergillus versicolor 170217 resulted in the isolation of six new (1–6) and 45 known (7–51) compounds. The structures of the new compounds were established on the basis of exhaustive analysis of their spectroscopic data and theoretical–statistical approaches including GIAO-NMR, TDDFT-ECD/ORD calculations, DP4+ probability analysis, and biogenetic consideration. Citriquinolinones A (1) and B (2) feature a unique isoquinolinone-embedded citrinin scaffold, representing the first exemplars of a citrinin–isoquinolinone hybrid. Dicitrinones K–L (3–4) are two new dimeric citrinin analogues with a rare CH-CH[sub.3] bridge. Biologically, frangula-emodin (32) and diorcinol (17) displayed remarkable anti-food allergic activity with IC[sub.50] values of 7.9 ± 3.0 μM and 13.4 ± 1.2 μM, respectively, while diorcinol (17) and penicitrinol A (20) exhibited weak inhibitory activity against Vibrio parahemolyticus, with MIC values ranging from 128 to 256 μM.
Journal Article
Evaluation of a novel saliva‐based epidermal growth factor receptor mutation detection for lung cancer: A pilot study
2016
Background
This article describes a pilot study evaluating a novel liquid biopsy system for non‐small cell lung cancer (NSCLC) patients. The electric field‐induced release and measurement (EFIRM) method utilizes an electrochemical biosensor for detecting oncogenic mutations in biofluids.
Methods
Saliva and plasma of 17 patients were collected from three cancer centers prior to and after surgical resection. The EFIRM method was then applied to the collected samples to assay for exon 19 deletion and p.L858 mutations. EFIRM results were compared with cobas results of exon 19 deletion and p.L858 mutation detection in cancer tissues.
Results
The EFIRM method was found to detect exon 19 deletion with an area under the curve (AUC) of 1.0 in both saliva and plasma samples in lung cancer patients. For L858R mutation detection, the AUC of saliva was 1.0, while the AUC of plasma was 0.98. Strong correlations were also found between presurgery and post‐surgery samples for both saliva (0.86 for exon 19 and 0.98 for L858R) and plasma (0.73 for exon 19 and 0.94 for L858R).
Conclusion
Our study demonstrates the feasibility of utilizing EFIRM to rapidly, non‐invasively, and conveniently detect epidermal growth factor receptor mutations in the saliva of patients with NSCLC, with results corresponding perfectly with the results of cobas tissue genotyping.
Journal Article
Temperature stability of magnetoresistance (MR) and MR enhancement in Lal-x(Srl-yAgy)xMn03 system
by
Yong-Gang Tang Gui-Ying Wang Guo-Qing Yan Qi-Xiang Song Ming-Yu Zhang Zhen-Sheng Peng
in
Ag掺杂
,
温度曲线
,
温度稳定性
2013
Polycrystalline samples of Lal-x(Srl-yAgy)x MnO3 (y = 0.0, 0.2, 0.4, 0.6, 1.0) were prepared by the solid-state reaction method. The temperature stability of magnetoresistance and magnetoresistance enhancement in Lal_x(Srl_yAgy)~MnO3 system with both univalent and bivalent elements doped at A site and with unchanged value of Mn~+/Mn4+ ratio were explored through the measurements of X-ray diffraction patterns, magnetiza- tion-temperature (M-T) curves, resistivity-temperature (p-T) curves and magnetoresistance-temperature (MR-T) curves. The results are as follows: there are two peaks in the p-T curves of the samples with Ag doping, one is caused by resistance change during the paramagnetism- ferromagnetism transition, and the other is from boundary- dependent scattering of conduction electrons on the boundaries of grains. The peak value of MR increases with increasing Ag doping content, and it increases from 8.2 % for y --- 0.2 to 29.6 % for y --- 1.0 under the magnetic field of B = 0.8 T; MR remains a constant of 12 % in the temperature range of 218-168 K for the sample with y = 1.0, and the temperature stability of MR is in favor of the practical application of MR.
Journal Article
Abnormal electric transport property and magnetoresistance stability of La-Sr-K-Mn-O system
by
Yong-Gang Tang Gui-Ying Wang Guo-Qing Yan Qi-Xiang Song Ming-Yu Zhang Zhen-Sheng Peng
in
Biomaterials
,
Chemistry and Materials Science
,
Disorder degree σ2
2013
The perovskite samples La1-x(Sr1-yKy)xMnO3 (y = 0.0, 0.2, 04, 0.6, 0.8) were prepared by the solid-state reaction method with comparatively low sintering tem- perature and with comparatively short sintering time, and the electric transport property and temperature stability of MR of this system were studied. The p-T curves show the abnormal phenomenon that with the increase of K doping amount, resistivity increases, and the insulator-metal transition temperature decreases, which is because the influence of the occupation disorder degree of A-site ions σ2 on the electric transport property of perovskite manga- nites is larger than that of the radius of A-site ions (rA). In the temperature range below 225 K, MR increases contin- uously with the decrease of temperature, which is the characteristic of low-field magnetoresistance; in the com- paratively wide temperature range near 250 K, the MR- T curves of all the samples are comparatively fiat, and the value of MR almost does not change with temperature, which shows the temperature stability of magnetoresis- tance, and can be explained by the competition between the low-field magnetoresistance induced by spin-dependent tunneling of surface phase and the intrinsic magnetoresis- tance of grain phase. The magnetoresistance value of the sample with y = 0.8 keeps at (7.92 ±0.36) % in the very wide temperature range of 225-275 K, and this is a goodreference for the preparation of this kind of sample with practical application value in the future.
Journal Article
Finite element modeling of consolidation process of Si C fiber-reinforced titanium matrix composites via matrix-coated fiber method
by
Xiang-Hong Xu Yan-Qing Yang Xian Luo Lin Qin Ju-Hong Lou Qing Sun
in
composites;Consolidation;Finite
,
element
,
fiber
2015
The consolidation process of SiC_f/Ti-6Al-4 V composites by matrix-coated fiber(MCF) method via hot pressing was investigated using finite element modeling(FEM).By analyzing the elastic-plastic contact deformation of the representative aligned coated fibers,the consolidation maps delineating the time-temperature-pressure relationship for full densification were constructed.Both the flow coefficient and the contact area coefficient used to describe the contact deformation were calculated according to the model.In addition,the effect of fiber content on matrix stress distribution was analyzed.The results show that fiber content is a significant factor that influences the densification process.Higher fiber content will lower the consolidation rate.
Journal Article
Functionalization of Brain Region-specific Spheroids with Isogenic Microglia-like Cells
Current brain spheroids or organoids derived from human induced pluripotent stem cells (hiPSCs) still lack a microglia component, the resident immune cells in the brain. The objective of this study is to engineer brain region-specific organoids from hiPSCs incorporated with isogenic microglia-like cells in order to enhance immune function. In this study, microglia-like cells were derived from hiPSCs using a simplified protocol with stage-wise growth factor induction, which expressed several phenotypic markers, including CD11b, IBA-1, CX3CR1, and P2RY12, and phagocytosed micron-size super-paramagnetic iron oxides. The derived cells were able to upregulate pro-inflammatory gene (TNF-α) and secrete anti-inflammatory cytokines (i.e., VEGF, TGF-β1, and PGE2) when stimulated with amyloid β42 oligomers, lipopolysaccharides, or dexamethasone. The derived isogenic dorsal cortical (higher expression of TBR1 and PAX6) and ventral (higher expression of NKX2.1 and PROX1) spheroids/organoids displayed action potentials and synaptic activities. Co-culturing the microglia-like cells (MG) with the dorsal (D) or ventral (V) organoids showed differential migration ability, intracellular Ca
2+
signaling, and the response to pro-inflammatory stimuli (V-MG group had higher TNF-α and TREM2 expression). Transcriptome analysis exhibited 37 microglia-related genes that were differentially expressed in MG and D-MG groups. In addition, the hybrid D-MG spheroids exhibited higher levels of immunoreceptor genes in activating members, but the MG group contained higher levels for most of genes in inhibitory members (except SIGLEC5 and CD200). This study should advance our understanding of the microglia function in brain-like tissue and establish a transformative approach to modulate cellular microenvironment toward the goal of treating various neurological disorders.
Journal Article
Honokiol improves depression-like behaviors in rats by HIF-1α- VEGF signaling pathway activation
by
Li, Yu
,
Chang, Hong-Sheng
,
Yu, Xue
in
antidepressant effect
,
Antidepressants
,
Biological activity
2022
Increasing evidence indicates that the pathogenesis of depression is closely linked to impairments in neuronal synaptic plasticity. Honokiol, a biologically active substance extracted from
Magnolia Officinalis
, has been proven to exert significant antidepressant effects. However, the specific mechanism of action remains unclear. In this study, PC12 cells and chronic unpredictable mild stress (CUMS) model rats were used to explore the antidepressant effects and potential mechanisms of honokiol
in vitro
and in rats.
In vitro
experiment, a cell viability detection kit was used to screen the concentration and time of honokiol administration. PC12 cells were administered with hypoxia-inducible factor-1α (HIF-1α) blocker, 2-methoxyestradiol (2-ME), and vascular endothelial growth factor receptor 2 (VEGFR-2) blocker, SU5416, to detect the expression of HIF-1α, VEGF, synaptic protein 1 (SYN 1), and postsynaptic density protein 95 (PSD 95) by western blotting. In effect, we investigated whether the synaptic plasticity action of honokiol was dependent on the HIF-1α-VEGF pathway.
In vivo
, behavioral tests were used to evaluate the reproducibility of the CUMS depression model and depression-like behaviors. Molecular biology techniques were used to examine mRNA and protein expression of the HIF-1α-VEGF signaling pathway and synaptic plasticity-related regulators. Additionally, molecular docking techniques were used to study the interaction between honokiol and target proteins, and predict their binding patterns and affinities. Experimental results showed that honokiol significantly reversed CUMS-induced depression-like behaviors. Mechanically, honokiol exerted a significant antidepressant effect by enhancing synaptic plasticity. At the molecular level, honokiol can activate the HIF-1α-VEGF signaling pathway
in vitro
and
in vivo
, as well as promote the protein expression levels of SYN 1 and PSD 95. Taken together, the results do not only provide an experimental basis for honokiol in the clinical treatment of depression but also suggest that the HIF-1α-VEGF pathway may be a potential target for the treatment of depression.
Journal Article