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Correlation of gut microbiota metabolite trimethylamine N-oxide with inflammatory levels and osteoporosis in patients with diabetic nephropathy
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作者 Zhang-Lei Pan Ming-Qiang Li +2 位作者 Jing Zhang Ling-Yu Xue Yan-Ping Shi 《World Journal of Diabetes》 2025年第11期99-111,共13页
BACKGROUND Diabetic nephropathy(DN)is one of the most serious microvascular complications of type 2 diabetes mellitus(T2DM),and its incidence increases with the global rise in diabetes prevalence.It is the leading cau... BACKGROUND Diabetic nephropathy(DN)is one of the most serious microvascular complications of type 2 diabetes mellitus(T2DM),and its incidence increases with the global rise in diabetes prevalence.It is the leading cause of chronic kidney disease and end-stage kidney disease.Patients with DN often experience complex metabolic disorders and chronic inflammatory states,which not only accelerate the decline of renal function but are also closely related to complications such as cardiovascular events and osteoporosis(OP),seriously compromising quality of life.With the in-depth research on the gut microbiota and the emergence of concepts such as the"gut-kidney axis"and the"enteric-bone axis",the key roles of the gut microbiota and its metabolites in metabolic disorders,inflammatory responses,and target organ damage have been increasingly recognized.However,the specific role of gut microbiota in the pathogenesis of DN remains to be further explored.The results obtained may provide evidence to better understand the pathogenesis of DN and to identify high-risk populations at an early stage.This research direction is of strategic significance.AIM To assess the correlation of the gut microbiota metabolite trimethylamine N-oxide(TMAO)with inflammatory marker levels and OP in patients with DN.METHODS A total of 115 patients diagnosed with type 2 DN and treated at the Department of Endocrinology,Second Affiliated Hospital of Shandong First Medical University from August 2022 to December 2024 were enrolled in the DN group,and 115 patients with T2DM without nephropathy were included in the T2DM group.The two groups were compared in terms of gastrointestinal microbiota abundance and relative abundance at the genus level;levels of TMAO,inflammatory markers[including C-reactive protein(CRP),interleukin-6(IL-6),interleukin-8(IL-8),and tumor necrosis factor-α(TNF-α)],and bone metabolism markers[including procollagen type I N-terminal propeptide(PINP),β-CrossLaps(β-CTX),and alkaline phosphatase(ALP)];and lumbar spine and hip bone mineral density(BMD).The correlation of TMAO level with inflammatory factor and bone metabolism indicator levels was further analyzed.RESULTS The DN group had higher Chao1 and Simpson indices of gastrointestinal microbiota diversity than the T2DM group,whereas the ACE and Shannon indices were lower(P<0.05).The relative abundance of Firmicutes was higher,and the relative abundances of Bacteroidetes,Proteobacteria,and Actinobacteria were lower in the DN group than in the T2DM group(P<0.05).CRP,IL-6,IL-8,TNF-α,and TMAO levels were considerably elevated in the DN group compared to the T2DM group(P<0.05).Moreover,the DN group had higher levels of bone turnover markers-including PINP,β-CTX,and ALP-but lower lumbar spine and hip BMDs than the T2DM group(P<0.05).TMAO level positively correlated with the Chao1 and Simpson indices and negatively correlated with the ACE and Shannon indices of gut microbiota diversity.TMAO level also negatively correlated with the relative abundances of Bacteroidetes,Proteobacteria,and Actinobacteria and positively correlated with the abundance of Firmicutes.Additionally,TMAO level positively correlated with the inflammatory markers CRP,IL-6,IL-8,and TNF-α,as well as with the bone turnover markers PINP,β-CTX,and ALP.It negatively correlated with lumbar spine and hip BMDs(P<0.05).CONCLUSION Inflammatory and bone metabolic levels in patients with DN were found to be associated with the gut microbiota–derived metabolite TMAO.Elevated TMAO levels may mediate inflammatory responses and bone metabolism disorders in patients with DN,thereby contributing to the progression of systemic inflammation and OP. 展开更多
关键词 Diabetic nephropathy Gut microbiota Trimethylamine n-oxide Inflammatory cytokines OSTEOPOROSIS
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Trimethylamine N-oxide aggravates vascular permeability and endothelial cell dysfunction under diabetic condition:in vitro and in vivo study 被引量:3
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作者 Jia-Yi Jiang Wei-Ming Liu +4 位作者 Qiu-Ping Zhang Hang Ren Qing-Ying Yao Gao-Qin Liu Pei-Rong Lu 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第1期25-33,共9页
AIM:To provide the direct evidence for the crucial role of trimethylamine N-oxide(TMAO)in vascular permeability and endothelial cell dysfunction under diabetic condition.METHODS:The role of TMAO on the in vitro biolog... AIM:To provide the direct evidence for the crucial role of trimethylamine N-oxide(TMAO)in vascular permeability and endothelial cell dysfunction under diabetic condition.METHODS:The role of TMAO on the in vitro biological effect of human retinal microvascular endothelial cells(HRMEC)under high glucose conditions was tested by a cell counting kit,wound healing,a transwell and a tube formation assay.The inflammation-related gene expression affected by TMAO was tested by real-time polymerase chain reaction(RT-PCR).The expression of the cell junction was measured by Western blotting(WB)and immunofluorescence staining.In addition,two groups of rat models,diabetic and non-diabetic,were fed with normal or 0.1%TMAO for 16wk,and their plasma levels of TMAO,vascular endothelial growth factor(VEGF),interleukin(IL)-6 and tumor necrosis factor(TNF)-αwere tested.The vascular permeability of rat retinas was measured using FITC-Dextran,and the expression of zonula occludens(ZO)-1 and claudin-5 in rat retinas was detected by WB or immunofluorescence staining.RESULTS:TMAO administration significantly increased the cell proliferation,migration,and tube formation of primary HRMEC either in normal or high-glucose conditions.RT-PCR showed elevated inflammation-related gene expression of HRMEC under TMAO stimulation,while WB or immunofluorescence staining indicated decreased cell junction ZO-1 and occludin expression after high-glucose and TMAO treatment.Diabetic rats showed higher plasma levels of TMAO as well as retinal vascular leakage,which were even higher in TMAO-feeding diabetic rats.Furthermore,TMAO administration increased the rat plasma levels of VEGF,IL-6 and TNF-αwhile decreasing the retinal expression levels of ZO-1 and claudin-5.CONCLUSION:TMAO enhances the proliferation,migration,and tube formation of HRMEC,as well as destroys their vascular integrity and tight connection.It also regulates the expression of VEGF,IL-6,and TNF-α. 展开更多
关键词 diabetic model trimethylamine n-oxide INFLAMMATION endothelial dysfunction RATS retinal microvascular endothelial cells
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Trimethylamine N-oxide generation process was influenced by the proportion and source of macronutrients in the diet 被引量:1
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作者 Chengcheng Wang Xuefeng Duan +5 位作者 Xiaoyue Li Jinyue Yang Changhu Xue Teruyoshi Yanagita Tiantian Zhang Yuming Wang 《Food Science and Human Wellness》 SCIE CSCD 2024年第2期649-658,共10页
Trimethylamine N-oxide(TMAO)is a risk factor of various chronic diseases,which was produced by metabolism from precursors to trimethylamine(TMA)in gut and the oxidation from TMA in liver.The TMA generation was influen... Trimethylamine N-oxide(TMAO)is a risk factor of various chronic diseases,which was produced by metabolism from precursors to trimethylamine(TMA)in gut and the oxidation from TMA in liver.The TMA generation was influenced by diet,mainly due to the rich TMAO precursors in diet.However,it was still unclear that the effects of different proportion and source of macronutrients in different dietary pattern on the production process of TMAO.Here,the generation of TMA from precursors and TMAO from TMA was determined after single oral choline chloride and intraperitoneal injection TMA,respectively,in mice fed with carbohydrates,proteins and fats in different proportion and sources.The results suggested that the generation of TMAO was increased by low non-meat protein and high fat via enhancing the production of TMAO from TMA,and decreased by plant protein and refined sugar via reducing TMA production from precursors in gut and TMAO transformation from TMA in liver.The high fat and high sugar diets accelerating the development of atherosclerosis did not increase the production of TMAO,the risk factor for atherosclerosis,which indicated that the dietary compositions rather than the elevated TMAO level might be a more key risk factor for atherosclerosis. 展开更多
关键词 Trimethylamine n-oxide(TMAO) Trimethylamine(TMA) Dietary composition MACRONUTRIENTS Gut microbiota
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New complexes of heteroaromatic N-oxides with europium,uranyl and zinc ions
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作者 Zbigniew Hnatejko 《Journal of Rare Earths》 SCIE EI CAS CSCD 2012年第6期552-558,共7页
New solid complexes of europium, uranyl and zinc ions with N-oxides of 4-chloro-2,6-dimethylpyridine, quinoline and 4-meth- oxyquinaldinic acid in presence different anions were obtained and characterized by elemental... New solid complexes of europium, uranyl and zinc ions with N-oxides of 4-chloro-2,6-dimethylpyridine, quinoline and 4-meth- oxyquinaldinic acid in presence different anions were obtained and characterized by elemental and TG analyses, IR and luminescence spectra. The compounds are crystalline, hydrated or anhydrous salts with colours typical of metal ions. Thermal studies showed that in hydrated salts lattice or coordination water molecules are present. A role of different anions in the formation of various types of the complexes is presented. 展开更多
关键词 COMPLEXES EUROPIUM 4-methoxyquinaldinic acid n-oxide 4-chloro-2 6-dimethylpyridine n-oxide quinoline n-oxide URANYL zinc
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Density Function Theory Study on Effects of Different Energetic Substituent Groups and Bridge Groups on Performance of Carbon-Linked Ditetrazole 2N-Oxides 被引量:2
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作者 吴琼 寇波 +2 位作者 张泽武 杭祖圣 朱卫华 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2017年第4期404-410,I0001,共8页
Based on the parent tetrazole 2N-oxide, six series of novel carbon-linked ditetrazole 2N- oxides with different energetic substituent groups (-NH2, -Na, -NO2, NF2, -NHNO2) and energetic bridge groups (-CH2-, -CH2-C... Based on the parent tetrazole 2N-oxide, six series of novel carbon-linked ditetrazole 2N- oxides with different energetic substituent groups (-NH2, -Na, -NO2, NF2, -NHNO2) and energetic bridge groups (-CH2-, -CH2-CH2-, -NH-, -N=N-, -NH-NH-) were designed. The overall performance and the effects of different energetic substituent groups and energetic bridge groups on the performance were investigated by density functional theory and electrostatic potential methods. The results showed that most of designed compounds have oxygen balance around zero, high heats of formation, high density, high energy, and acceptable sensitivity, indicating that tetrazole N-oxide is a useful parent energetic compound employed for obtaining high energy compounds, even only combined with some very common energetic substituent groups and bridge groups. Comprehensively considering the effects on energy and sensitivity, the -NO2, -NF2, -NH- and-NH-NH- are appropriate substituent groups for combining tetrozale N-oxide to design new energetic compounds, while -NH2, -Na, -CH2-CH2-, and -N=N- are inappropriate. 展开更多
关键词 TETRAZOLE n-oxide High energy Bridge group Density functional theory
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Trimethylamine N-oxide attenuates high-fat high-cholesterol dietinduced steatohepatitis by reducing hepatic cholesterol overload in rats 被引量:12
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作者 Ze-Hua Zhao Feng-Zhi Xin +5 位作者 Da Zhou Ya-Qian Xue Xiao-Lin Liu Rui-Xu Yang Qin Pan Jian-Gao Fan 《World Journal of Gastroenterology》 SCIE CAS 2019年第20期2450-2462,共13页
BACKGROUND Trimethylamine N-oxide (TMAO) has been shown to be involved in cardiovascular disease (CVD). However, its role in nonalcoholic steatohepatitis (NASH) is unknown. AIM To determine the effect of TMAO on the p... BACKGROUND Trimethylamine N-oxide (TMAO) has been shown to be involved in cardiovascular disease (CVD). However, its role in nonalcoholic steatohepatitis (NASH) is unknown. AIM To determine the effect of TMAO on the progression of NASH. METHODS A rat model was induced by 16-wk high-fat high-cholesterol (HFHC) diet feeding and TMAO was administrated by daily oral gavage for 8 wk. RESULTS Oral TMAO intervention attenuated HFHC diet-induced steatohepatitis in rats. Histological evaluation showed that TMAO treatment significantly alleviated lobular inflammation and hepatocyte ballooning in the livers of rats fed a HFHC diet. Serum levels of alanine aminotransferase and aspartate aminotransferase were also decreased by TMAO treatment. Moreover, hepatic endoplasmic reticulum (ER) stress and cell death were mitigated in HFHC diet-fed TMAOtreated rats. Hepatic and serum levels of cholesterol were both decreased by TMAO treatment in rats fed a HFHC diet. Furthermore, the expression levels of intestinal cholesterol transporters were detected. Interestingly, cholesterol influxrelated Niemann-Pick C1-like 1 was downregulated and cholesterol efflux-related ABCG5/8 were upregulated by TMAO treatment in the small intestine. Gut microbiota analysis showed that TMAO could alter the gut microbial profile and restore the diversity of gut flora. CONCLUSION These data suggest that TMAO may modulate the gut microbiota, inhibit intestinal cholesterol absorption, and ameliorate hepatic ER stress and cell death under cholesterol overload, thereby attenuating HFHC diet-induced steatohepatitis in rats. Further studies are needed to evaluate the influence on CVD and define the safe does of TMAO treatment. 展开更多
关键词 Gut microbiota TRIMETHYLAMINE n-oxide NONALCOHOLIC STEATOHEPATITIS Endoplasmic reticulum stress CHOLESTEROL
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TsCl-promoted sulfonylation of quinoline N-oxides with sodium sulfinates in water 被引量:6
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作者 Sha Peng Yan-Xi Song +5 位作者 Jun-Yi He Shan-Shan Tang Jia-Xi Tan Zhong Cao Ying-Wu Lin Wei-Min He 《Chinese Chemical Letters》 SCIE CAS CSCD 2019年第12期2287-2290,共4页
An eco-friendly protocol for the synthesis of various 2-sulfonyl quinolines/pyridines through sulfonylation of heteroaromatic N-oxides with sodium sulfinates in water at ambient temperature under metal-and oxidant-fre... An eco-friendly protocol for the synthesis of various 2-sulfonyl quinolines/pyridines through sulfonylation of heteroaromatic N-oxides with sodium sulfinates in water at ambient temperature under metal-and oxidant-free conditions has been developed.The mild reaction conditions,high reaction efficiency,operational simplicity,short reaction time and remarkable functional-group compatibility make the developed protocol very attractive for the preparation of 2-sulfonyl N-heteroaromatic compounds. 展开更多
关键词 Quinoline n-oxides 2-Sulfonylquinolines Sodium sulfinates SULFONYLATION In water
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Synthesis and Crystal Structure of a Zinc(II) Complex Salt with the Schiff Base of Picolinaldehyde N-oxide and Semicarbazone 被引量:5
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作者 YU Qing ZHU Li-Gang BIAN He-Dong DENG Ji-Hua YANG Xiao-E GUO Gui-Quan LIANG Hong 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2005年第11期1271-1275,共5页
The title zinc(Ⅱ) complex salt [Zn(H2O)6](ClO4)2-(PNOS)4, where PNOS is derived from picolinaldehyde N-oxide with semicarbazone, has been prepared and structurally characterized by X-ray single-crystal analys... The title zinc(Ⅱ) complex salt [Zn(H2O)6](ClO4)2-(PNOS)4, where PNOS is derived from picolinaldehyde N-oxide with semicarbazone, has been prepared and structurally characterized by X-ray single-crystal analysis. It crystallizes in triclinic, space group PI with a = 7.529(3), b = 10.206(4), c = 14.678(6)A, a = 86.293(6), β= 87.686(7), γ= 81.382(6)°, C28H44Cl2N16O22Zn, Mr = 1093.06, V = 1112.3(8) ,A^3 Z = 1, Dc = 1.632 g/cm^3, S = 1.089, μ(MoKa) = 0.773 mm^-1, F(000) = 564, the final R = 0.0438 and wR = 0.1076 for 3888 independent reflections with Rint = 0.0224. The crystal structure possesses a [Zn(H2O)6]^2+ cation, two ClO4^- anions and four PNOSs. In the crystal structure, Zn^2+ cation is located at the symcenter and coordinated by six water molecules. In [Zn(H2O)6]^2+, an elongate octahedral complex cation, the average Zn-O bond length is 2.087(2) A. There exist a lot of H bonds in the structure, linking the cation [Zn(H2O)6]^2+, anion ClO4^- and PNOS to form a 3D network. 展开更多
关键词 zinc(Ⅱ) complex salt picolinaldehyde n-oxide SEMICARBAZONE crystal structure Schiff base
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Hydrothermal Synthesis, Crystal Structure and Fluorescent Property of a Cd(Ⅱ) Complex Based on Biimidazole and Isonicotinate-N-oxide 被引量:4
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作者 毛稳玲 胡宗球 丁瑜 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2010年第4期587-591,共5页
A new complex [Cd(H2biim)2(H2O)2]·(ino)2·4H2O (H2biim = 2,2'-biimidazole, ino = isonicotinate-N-oxide) has been prepared and characterized by single-crystal X-ray diffraction analysis, IR and fluore... A new complex [Cd(H2biim)2(H2O)2]·(ino)2·4H2O (H2biim = 2,2'-biimidazole, ino = isonicotinate-N-oxide) has been prepared and characterized by single-crystal X-ray diffraction analysis, IR and fluorescence spectra analysis. The crystal is of triclinic system, space group P1 with a = 7.5380(6), b = 8.0402(7), c = 13.5094(11) , α = 104.269(1), β = 93.604(1), γ = 98.349(1)°, V = 780.93(11) 3, Mr = 765.00, Dc = 1.627 g/cm3, F(000) = 390, μ = 0.776 mm-1 and Z = 1. The final R = 0.0322 and wR = 0.0825 for 7038 observed reflections with I 2σ(I) and R = 0.0341 and wR = 0.0832 for all data. The title complex exhibits an infinite chain-like structure through bridging isonicotinate-N-oxide. Strong interchain hydrogen bonds between isonicotinate-N-oxide and H2biim result in the robust 3-D supramolecular architecture. Moreover, the complex shows strong photoluminescence with emission maximum at λ = 401 nm upon λex = 330 nm. 展开更多
关键词 cadmium(Ⅱ) complex crystal structure 2 2-biimidazole isonicotinc acid n-oxide hydrothermal synthesis fluorescent property
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Toxic effects of strychnine and strychnine N-oxide on zebrafish embryos 被引量:2
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作者 LI Yu QI Xu +2 位作者 YANG Yu-Wei PAN Yang BIAN Hui-Min 《Chinese Journal of Natural Medicines》 SCIE CAS CSCD 2014年第10期760-767,共8页
AIM: The application of strychnine(S) is limited due to its toxicity; strychnine N-oxide(SNO) is a derivative of strychnine. The aim was to employ zebrafish embryos to investigate and compare the developmental toxicit... AIM: The application of strychnine(S) is limited due to its toxicity; strychnine N-oxide(SNO) is a derivative of strychnine. The aim was to employ zebrafish embryos to investigate and compare the developmental toxicity induced by S and SNO. METHODS: The toxicity of S and SNO was examined through the hatching rate and survival rate. Morphological changes of the zebrafish were observed with a dissecting microscope. Apoptosis was detected through acridine orange(AO) staining and flow cytometry. Apoptotic genes were measured by RT-PCR. RESULTS: Embryo malformation was observed in the embryos exposed to S at 200 μmol·L–1. When SNO concentration was increased to 1 mmol·L–1, scoliolosis, and pericardial edema could be seen in some embryos. Results from fluorescence microscopy and flow cytometry analysis showed that S at 200 μmol·L–1 induced apoptosis, whereas the apoptotic rate in the SNO-treated group(200 μmol·L–1) was much lower than that in the S group. RT-PCR analysis showed that p53 mRNA expression and the ratio of Bax/Bcl-2 in the S group were significantly altered compared with the control group(*P < 0.05). Moreover, Bax mRNA expression in both S and SNO group were significantly different from that in the control group(**P <0.01). CONCLUSION: These results lead to the conclusion that SNO has significantly lower toxicity than S in zebrafish embryos. 展开更多
关键词 STRYCHNINE Strychnine n-oxide TOXICITY Zebrafish embryos APOPTOSIS
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Arylation of pyridine N-oxides via a ligand-free Suzuki reaction in water 被引量:1
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作者 Chun Liu Shao-Ke Zhang +1 位作者 Yi-Xia Zhang Zi-Lin Jin 《Chinese Chemical Letters》 SCIE CAS CSCD 2015年第1期55-57,共3页
We report a practical and highly efficient protocol for the arylation of pyridine N-oxides with arylboronic acid through palladium-catalyzed Suzuki reaction in water.This ligand-free Suzuki reaction is performed in th... We report a practical and highly efficient protocol for the arylation of pyridine N-oxides with arylboronic acid through palladium-catalyzed Suzuki reaction in water.This ligand-free Suzuki reaction is performed in the presence of diisopropylamine and gives 2-or 3-arylated pyridyl N-oxide derivatives in good to excellent yields within 1 h. 展开更多
关键词 Pyridine n-oxides ARYLATION PALLADIUM Suzuki reaction WATER
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Distinct influence of trimethylamine N-oxide and high hydrostatic pressure on community structure and culturable deep-sea bacteria 被引量:1
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作者 ZHANG Chan ZHANG Wei-jia +3 位作者 YIN Qunjian LI Xuegong QI Xiaoqing WU Long-fei 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2020年第2期364-377,共14页
Trimethylamine N-oxide(TMAO)is one of the most important nutrients for bacteria in the deep-sea environment and is capable of improving pressure tolerance of certain bacterial strains.To assess the impact of TMAO on m... Trimethylamine N-oxide(TMAO)is one of the most important nutrients for bacteria in the deep-sea environment and is capable of improving pressure tolerance of certain bacterial strains.To assess the impact of TMAO on marine microorganisms,especially those dwelling in the deep-sea environment,we analyzed the bacterial community structure of deep-sea sediments after incubated under different conditions.Enrichments at 50 MPa and 0.1 MPa revealed that TMAO imposed a greater influence on bacterial diversity and community composition at atmospheric pressure condition than that under high hydrostatic pressure(HHP).We found that pressure was the primary factor that determines the bacterial community.Meanwhile,in total,238 bacterial strains were isolated from the enrichments,including 112 strains a ffiliated to 16 genera of 4 phyla from the Yap Trench and 126 strains a ffiliated to 11 genera of 2 phyla from the Mariana Trench.Treatment of HHP reduced both abundance and diversity of isolates,while the presence of TMAO mainly af fected the diversity of isolates obtained.In addition,certain genera were isolated only when TMAO was supplemented.Taken together,we demonstrated that pressure primarily defines the bacterial community and culturable bacterial isolates.Furthermore,we showed for the first time that TMAO had distinct influences on bacterial community depending on the pressure condition.The results enriched the understanding of the significance of TMAO in bacterial adaptation to the deep-sea environment. 展开更多
关键词 deep-sea bacteria high hydrostatic pressure(HHP) trimethylamine n-oxide(TMAO) community structure
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Synthesis and Structure of the Manganese Complexwith 2-Aminopyridine N-oxide 被引量:1
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作者 牛德仲 路再生 +1 位作者 孙柏旺 宋宝林 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2001年第3期180-182,共3页
The complex Mn(apo)6Cl2 (apo=2-aminopyridine N-oxide) was obtained by the reaction of MnCl2(4H2O with apo(HCl and NaOH in ethanol. A single-crystal X-ray study shows that the complex is mononuclear with octahedral coo... The complex Mn(apo)6Cl2 (apo=2-aminopyridine N-oxide) was obtained by the reaction of MnCl2(4H2O with apo(HCl and NaOH in ethanol. A single-crystal X-ray study shows that the complex is mononuclear with octahedral coordination environment (MnC30H36N12O6Cl2). The oxygen atoms from apo ligands coordinate to the manganese atom forming Mn(apo)6Cl2. The compound Mn(apo)6Cl2 is hexagonally symmetric with space group R3, lattice constants: a = 12.010(2), b = 12.010(2), c = 20.232(4) ?, ( = 120(, V= 2527.4(7) ?3, Z=3, Mr =786.55, Dc=1.550 g/cm3, (= 0.614mm-1, F(000) = 1221, R = 0.0541, Rw = 0.0580 for 1229 reflections with I>2((I). The distances between Mn(II) and O atoms are in the range from 2.171(5) to 2.184(5) ?, and the distance between the chlorine anion and N atom of amido group is 3.3 ?. The dihedral angle between two adjacent pyridine ring planes is 59.19 (0.17)°. 展开更多
关键词 crystal structure manganese(II) 2-aminopyridine n-oxide COMPLEX
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Synthesis and Structure of bis(μ-2-aminopyridine N-oxide)-bis[dichlorocopper(II)] 被引量:1
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作者 牛德绅 路再生 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2001年第4期270-273,共4页
The complex [Cu2(apo)4Cl4]·2H2O (apo=2-aminopyridine N-oxide) was obtained. A single- crystal X-ray study shows that the complex is a binuclear compound (Cu2C20H28Cl4N8O6). The coordination geometry about e... The complex [Cu2(apo)4Cl4]·2H2O (apo=2-aminopyridine N-oxide) was obtained. A single- crystal X-ray study shows that the complex is a binuclear compound (Cu2C20H28Cl4N8O6). The coordination geometry about each copper atom is best described as a distorted square pyramid. The compound [Cu2(apo)4Cl4]·2H2O belongs to the triclinic system with space group P, lattice constants: a = 7.8550(7), b = 8.5378(7), c = 12.082(1) ?, α = 72.807(1), β = 77.641(1), γ = 70.800(1)(, V =724.85(11) ?3, Z=1, Mr =745.38, Dc=1.708 g/cm3, μ =1.886mm-1, F(000) =378, R=0.0359, wR2=0.0884 for 2220 reflections with I >2σ(I). The distances between Cu(II) and O atoms are in the range from 1.934(2) to 2.042(2)?. The distance between two copper atoms Cu-Cu(A) is 3.2978(8) ?. The distances of Cu-Cl(1) and Cu-Cl(2) are 2.2322(9), 2.5095(10) ?, respectively. There is no evident hydrogen bond between N and Cl. 展开更多
关键词 crystal structure copper(II) 2-aminopyridine n-oxide binuclear complex
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Semi-synthesis and Crystal Structure of Sophoridine N-oxide 被引量:1
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作者 赵斌 禹洁 +3 位作者 李欣儒 龙伟 张军帅 刘培勋 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2012年第3期396-400,共5页
Sophoridine N-oxide was synthesized and characterized by 1H-NMR,EI-MS,IR and elemental analysis,together with X-ray single-crystal diffraction analysis,and its crystal structure was reported for the first time.The cry... Sophoridine N-oxide was synthesized and characterized by 1H-NMR,EI-MS,IR and elemental analysis,together with X-ray single-crystal diffraction analysis,and its crystal structure was reported for the first time.The crystal belongs to the orthorhombic system,space group P212121 with a = 8.321(2),b = 15.650(3),c = 24.352(5) ,V = 3171.1(11) 3,Z = 8,Dc = 1.258 g/cm3,λ(CuKα) = 1.54178,F(000) = 1440,the final R = 0.0351 and wR = 0.0970.The crystal structure shows Sophoridine N-oxide crystallizes with two host molecules of similar conformation and four water solvent molecules in the asymmetric unit.In the crystal structure,intermolecular O-H…O hydrogen bonds link the constituent molecules into a 2D layer structure,which further extends to a 3D supramolecular architecture via Van der Waals interactions and intermolecular O-H…O hydrogen bonds. 展开更多
关键词 SEMI-SYNTHESIS sophoridine n-oxide crystal structure
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PREPARATION AND MECHANISM OF 7,17-SECO C_(19)-DITERPENOID ALKALOIDS VIA PYROLYSIS OF THEIR N-OXIDES IN DIGLYME 被引量:1
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作者 S.W.Pelletier 《Chinese Chemical Letters》 SCIE CAS CSCD 1991年第2期103-106,共4页
A new preparation method of the N-ethyl 7,17-seco C_(19)-diterpenoid alkaloids(5)and(6)by pyrolysis of the N-oxides(3)and(4),respectively, in anhydrous diglyme is described.A probable reaction mechanism for the pyroly... A new preparation method of the N-ethyl 7,17-seco C_(19)-diterpenoid alkaloids(5)and(6)by pyrolysis of the N-oxides(3)and(4),respectively, in anhydrous diglyme is described.A probable reaction mechanism for the pyroly- sis is presented and studied preliminarily. 展开更多
关键词 DITERPENOID ALKALOIDS VIA PYROLYSIS OF THEIR n-oxideS IN DIGLYME PREPARATION AND MECHANISM OF 7 17-SECO C
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Contribution of trimethylamine N-oxide on the growth and pressure tolerance of deep-sea bacteria
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作者 YIN Qunjian ZHANG Weijia +4 位作者 LI Xuegong ZHOU Lihong QI Xiaoqing ZHANG Chan WU Long-Fei 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2019年第1期210-222,共13页
Trimethylamine N-oxide(TMAO) is widely dispersed in marine environments and plays an important role in the biogeochemical cycle of nitrogen. Diverse marine bacteria utilize TMAO as carbon and nitrogen sources or as el... Trimethylamine N-oxide(TMAO) is widely dispersed in marine environments and plays an important role in the biogeochemical cycle of nitrogen. Diverse marine bacteria utilize TMAO as carbon and nitrogen sources or as electron acceptor in anaerobic respiration. Alteration of respiratory component according to the pressure is a common trait of deep-sea bacteria. Deep-sea bacteria from dif ferent genera harbor high hydrostatic pressure(HHP) inducible TMAO reductases that are assumed to be constitutively expressed in the deep-sea piezosphere and facilitating quick reaction to TMAO released from ?sh which is a potential nutrient for bacterial growth. However, whether deep-sea bacteria universally employ this strategy remains unknown. In this study, 237 bacterial strains affliated to 23 genera of Proteobacteria,Bacteroidetes, Firmicutes and Actinobacteria were isolated from seawater, sediment or amphipods collected at dif ferent depths. The pressure tolerance and the utilization of TMAO were examined in 74 strains. The results demonstrated no apparent correlation between the depth where the bacteria inhabit and their pressure tolerance, regarding to our samples. Several deep-sea strains from the genera of Alteromonas, Halomonas,Marinobacter, Photobacterium, and Vibrio showed capacity of TMAO utilization, but none of the isolated Acinebacter, Bacillus, Brevundimonas, Muricauda, Novosphingobium, Rheinheimera, Sphingobium and Stenotrophomonas did, indicating the utilization of TMAO is a species-speci?c feature. Furthermore, we noticed that the ability of TMAO utilization varied among strains of the same species. TMAO has greater impact on the growth of deep-sea isolates of Vibrio neocaledonicus than shallow-water isolates. Taken together, the results describe for the ?rst time the TMAO utilization in deep-sea bacterial strains, and expand our understanding of the physiological characteristic of marine bacteria. 展开更多
关键词 marine BACTERIA TRIMETHYLAMINE n-oxide(TMAO) high hydrostatic pressure(HHP) PRESSURE TOLERANCE phenotype
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Crebanine N-oxide, a natural aporphine alkaloid isolated from Stephania hainanensis, induces apoptosis and autophagy in human gastric cancer SGC-7901 cells
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作者 Zheng-Wen Wang Hao Liu +4 位作者 Geng-Tai Ye Zhi-Yong Sheng Yan-Feng Hu Yin-Feng Tan Guo-Xin Li 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2020年第5期224-231,共8页
Objective: To investigate the cytotoxic effects and the potential mechanisms of crebanine N-oxide in SGC-7901 gastric adenocarcinoma cells. Methods: The cytotoxicity of crebanine N-oxide was evaluated by 3-(4,5-dimeth... Objective: To investigate the cytotoxic effects and the potential mechanisms of crebanine N-oxide in SGC-7901 gastric adenocarcinoma cells. Methods: The cytotoxicity of crebanine N-oxide was evaluated by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide assay and cellular morphology was observed under a microscope. Cell apoptosis was determined by flow cytometry using propidium iodide staining. The expression levels of apoptotic-related proteins, cleaved caspase-3, cytochrome C, p53 and Bax, and autophagyrelated proteins p62, beclin1 and LC3 were detected by Western blotting assays. Results: Crebanine N-oxide treatment significantly inhibited the proliferation of SGC-7901 cells in a dose-dependent and timedependent manner via induction of G2-phase cell cycle arrest, apoptosis, and autophagy in SGC-7901 cells.Conclusions: Crebanine N-oxide could inhibit the growth of gastric cancer cells by promoting apoptosis and autophagy and could be used as a potential agent for treating gastric cancer. 展开更多
关键词 Crebanine n-oxide Gastric cancer SGC-7901 cells APOPTOSIS AUTOPHAGY
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N-Oxide heterocycles and imidazoles replacing ring D of calanolides against Mycobacterium tuberculosis
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作者 Zi-Jie Liu Xiao-Yong Guo Gang Liu 《Chinese Chemical Letters》 SCIE CAS CSCD 2016年第1期51-54,共4页
We have explored the chemistry of N-oxide heterocycles and imidazoles replacing ring D of the natural product(+)-calanolide A, and have synthesized 12 new analogues, two of which were active against both R Mtb and ... We have explored the chemistry of N-oxide heterocycles and imidazoles replacing ring D of the natural product(+)-calanolide A, and have synthesized 12 new analogues, two of which were active against both R Mtb and NR Mtb with MIC values of 12.5 mg/m L, which would lead to further optimization for more potent anti-TB candidates. 展开更多
关键词 Mycobacterium tuberculosis (+)-Calanolide A n-oxide heterocycle Benzoimidazole Bioreductive drug
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Ternary Complexes of Rare Earth Nitrate with B-15-C-5 and 4-Picoline N-Oxide
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作者 杨瑞娜 赵继周 朱文祥 《Journal of Rare Earths》 SCIE EI CAS CSCD 1991年第3期161-164,共4页
A series of ternary complexes of rare earth(Ⅲ)nitrate with benzo-15-crown-5 and 4-picoline N-oxide have been prepared.They have the general formula of RE(NO_3)_3·2(4-picNO)·3H_2O·(1/2)(B-15-C-5) (RE=La... A series of ternary complexes of rare earth(Ⅲ)nitrate with benzo-15-crown-5 and 4-picoline N-oxide have been prepared.They have the general formula of RE(NO_3)_3·2(4-picNO)·3H_2O·(1/2)(B-15-C-5) (RE=La~Tm).Their physico-chemical properties have also been studied with conductance,thermal analysis and IR absorption spectroscopy. 展开更多
关键词 Rare earth Crown ether 4-picoline n-oxide Ternary complex
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