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Metabolomics in human type 2 diabetes research

null

《医学前沿（英文）》 2013年 第7卷 第1期   页码 4-13 doi: 10.1007/s11684-013-0248-4

摘要：

The high prevalence of diabetes and diabetic complications has caused a huge burden on the modern society. Although scientific advances have led to effective strategies for preventing and treating diabetes over the past several decades, little progress has been made toward curing the disease or even getting it under control, from a public health and overall societal standpoint. There is still a lack of reliable biomarkers indicative of metabolic alterations associated with diabetes and different drug responses, highlighting the need for the development of early diagnostic and prognostic markers for diabetes and diabetic complications. The emergence of metabolomics has allowed researchers to systemically measure the small molecule metabolites, which are sensitive to the changes of both environmental and genetic factors and therefore, could be regarded as the link between genotypes and phenotypes. During the last decade, the progression made in metabolomics has provided insightful information on disease development and disease onset prediction. Recent studies using metabolomics approach coupled with statistical tools to predict incident diabetes revealed a number of metabolites that are significantly altered, including branched-chain and aromatic amino acids, such as isoleucine, leucine, valine, tyrosine and phenylalanine, as diagnostic or highly-significant predictors of future diabetes. This review summarizes the current findings of metabolomic studies in human investigations with the most common form of diabetes, type 2 diabetes.

关键词： metabolomics     type 2 diabetes     metabolic pathway     mass spectrometry     nuclear magnetic resonance (NMR)    

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Application and mechanism of polysaccharide extracted from Enteromorpha to remove nano-ZnO and humic acid in coagulation process

Jianzhang Sun, Baoyu Gao, Yuanxia Luo, Moxi Xue, Xing Xu, Qinyan Yue, Yan Wang

《环境科学与工程前沿（英文）》 2018年 第12卷 第3期 doi: 10.1007/s11783-018-1029-8

摘要： Enteromorpha polysaccharide (Ep) extracted from alga a novel green coagulant aid for nanoparticles (NPs) and heavy metal ions removal and the structure of EP was intensively studied in this study. The integration of Ep with polyaluminum chloride (PAC-Ep) coagulants exhibited higher coagulation performance than that of the polyaluminum chloride (PAC) because of the negatively charged NPs suspension and humic aid (HA) solution. Significant high removal efficiencies of dissolved organic matter (94.1%), turbidity (99.3%) and Zn ions (69.3%) were achieved by the PAC-Ep coagulants. The dual-coagulation properties of PAC-Ep for different pollutants was based on multiple mechanisms, including (i) Al charge neutralization; (ii) hydroxy aluminum hydroxyl bridging formed polynuclearhydroxy complexes bridge and sweep colloidal particles; (iii) adsorption and bridging of Ep chain for the NPs and heavy metal ions. Results indicated that the destabilization of colloid was induced by the coexisting HA and higher removal was achieved as ions adsorption was enhance in the presence of HA complexation. On the basis of that, the extraction of polysaccharide is a promising candidate for its high coagulation performance in water treatment.

关键词： Algal Extraction     Enteromorpha polysaccharide     1H-13C nuclear magnetic resonance (NMR)     Fourier transform infrared (FTIR)     X-ray photoelectron spectroscopy (XPS)     Coagulation mechanism.    

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Discovery of the mechanisms of acupuncture in the treatment of migraine based on functional magneticresonance imaging and omics

《医学前沿（英文）》   页码 993-1005 doi: 10.1007/s11684-023-0989-7

摘要： Migraine is one of the most prevalent and disabling neurological disease, but the current pharmacotherapies show limited efficacy and often accompanied by adverse effects. Acupuncture is a promising complementary therapy, but further clinical evidence is needed. The influence of acupuncture on migraine is not an immediate effect, and its mechanism remains unclear. This study aims to provide further clinical evidence for the anti-migraine effects of acupuncture and explore the mechanism involved. A randomized controlled trial was performed among 10 normal controls and 38 migraineurs. The migraineurs were divided into blank control, sham acupuncture, and acupuncture groups. Patients were subjected to two courses of treatment, and each treatment lasted for 5 days, with an interval of 1 day between the two courses. The effectiveness of treatment was evaluated using pain questionnaire. The functional magnetic resonance imaging (fMRI) data were analyzed for investigating brain changes induced by treatments. Blood plasma was collected for metabolomics and proteomics studies. Correlation and mediation analyses were performed to investigate the interaction between clinical, fMRI and omics changes. Results showed that acupuncture effectively relieved migraine symptoms in a way different from sham acupuncture in terms of curative effect, affected brain regions, and signaling pathways. The anti-migraine mechanism involves a complex network related to the regulation of the response to hypoxic stress, reversal of brain energy imbalance, and regulation of inflammation. The brain regions of migraineurs affected by acupuncture include the lingual gyrus, default mode network, and cerebellum. The effect of acupuncture on patients’ metabolites/proteins may precede that of the brain.

关键词： acupuncture     migraine     fMRI     metabolome     proteome    

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Machine learning for detecting mesial temporal lobe epilepsy by structural and functional neuroimaging

Baiwan Zhou, Dongmei An, Fenglai Xiao, Running Niu, Wenbin Li, Wei Li, Xin Tong, Graham J Kemp, Dong Zhou, Qiyong Gong, Du Lei

《医学前沿（英文）》 2020年 第14卷 第5期   页码 630-641 doi: 10.1007/s11684-019-0718-4

摘要： Mesial temporal lobe epilepsy (mTLE), the most common type of focal epilepsy, is associated with functional and structural brain alterations. Machine learning (ML) techniques have been successfully used in discriminating mTLE from healthy controls. However, either functional or structural neuroimaging data are mostly used separately as input, and the opportunity to combine both has not been exploited yet. We conducted a multimodal ML study based on functional and structural neuroimaging measures. We enrolled 37 patients with left mTLE, 37 patients with right mTLE, and 74 healthy controls and trained a support vector ML model to distinguish them by using each measure and the combinations of the measures. For each single measure, we obtained a mean accuracy of 74% and 69% for discriminating left mTLE and right mTLE from controls, respectively, and 64% when all patients were combined. We achieved an accuracy of 78% by integrating functional data and 79% by integrating structural data for left mTLE, and the highest accuracy of 84% was obtained when all functional and structural measures were combined. These findings suggest that combining multimodal measures within a single model is a promising direction for improving the classification of individual patients with mTLE.

关键词： mesial temporal lobe epilepsy     functional magnetic resonance imaging     structural magnetic resonance imaging     machine learning     support vector machine    

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全氟化碳乳剂19F磁共振成像的最新进展 Review

Anne H. Schmieder,Shelton D. Caruthers,Jochen Keupp,Samuel A. Wickline,Gregory M. Lanza

《工程（英文）》 2015年 第1卷 第4期   页码 475-489 doi: 10.15302/J-ENG-2015103

摘要：

19F磁共振成像(MRI) 的研究可追溯到30多年前。在这30多年间，氢原子核(1H)成像技术迅速发展，并在全球得到广泛应用，使得磁共振成像成为生物医学诊断成像技术中不可缺少的支柱。多年来，由于各种原因，对19F成像技术的研究进展缓慢。但是在过去的十年间，尤其是最近几年，19F成像的研究和临床相关性呈爆发式发展。部分原因归结为MRI仪器、19F/1H线圈设计以及临床前和临床核磁共振仪的超高速脉冲序列的发展。这些成就再加上对解剖生理学分子成像技术的兴趣以及一批创新造影剂的出现使19F的概念进入了早期的临床评估中。本篇综述重点探讨以液态全氟化碳化合物为基础的造影剂，并试图呈现这段丰富的研究和发展历史。

关键词： 氟     磁共振成像(MRI)     双调线圈     全氟化碳     血管生成术     细胞标记    

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Progress in NMR-based metabolomics of

Qifang PAN,Jingya ZHAO,Yuliang WANG,Kexuan TANG

《农业科学与工程前沿（英文）》 2015年 第2卷 第3期   页码 195-204 doi: 10.15302/J-FASE-2015063

摘要： Metabolomics has been rapidly developed as an important field in plant sciences and natural products chemistry. As the only natural source for a diversity of monoterpenoid indole alkaloids (MIAs), especially the low-abundance antitumor agents vinblastine and vincristine, is highly valued and has been studied extensively as a model for medicinal plants improvement. Due to multistep enzymatic biosynthesis and complex regulation, genetic modification in the MIA pathway has resulted in complicated changes of both secondary and primary metabolism in , affecting not only the MIA pathway but also other pathways. Research at the metabolic level is necessary to increase knowledge on the genetic regulation of the whole metabolic network connected to MIA biosynthesis. Nuclear magnetic resonance (NMR) is a very suitable and powerful complementary technique for the identification and quantification of metabolites in the plant matrix. NMR-based metabolomics has been used in studies of for pathway elucidation, understanding stress responses, classification among different cultivars, safety and quality controls of transgenic plants, cross talk between pathways, and diversion of carbon fluxes, with the aim of fully unravelling MIA biosynthesis, its regulation and the function of the alkaloids in the plant from a systems biology point of view.

关键词： Catharanthus roseus     monoterpenoid indole alkaloids     NMR     metabolomics    

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Copolymerization of 1-butene and 1-hexene with supported titanium catalyst

ZHAO Yongxian, SHAO Huafeng, WANG Bo, YAO Wei, HUANG Baochen

《化学科学与工程前沿（英文）》 2007年 第1卷 第3期   页码 304-309 doi: 10.1007/s11705-007-0056-y

摘要： With TiCl/MgCl (Ti) and Al(-Bu) (Al) as catalysts, the thermoplastic copolymer of 1-butene(Bt) and 1-hexene(He) was synthesized successfully. The effects of Bt/He, Ti/(He+Bt), Al/Ti, temperature and reaction time on conversion, catalyst efficiency(CE), intrinsic viscosity([η]) and insoluble content were studied. The copolymer was analyzed with Fourier transform-infrared (FTIR) and nuclear magnetic resonance (H-NMR). Results showed that the optimal polymerization conditions were: He/Bt = 0.25, temperature 40ºC–50ºC, Al/Ti = 400–500, Ti/(Bt+He) = 3×10-4*times;10, time 4 h. Intrinsic viscosity was found to increase with increasing Ti/(Bt+He) and decreasing Al/Ti and polymerization temperature. When the molar content of He, Al/Ti and polymerization temperature increased, the insoluble content in CHCl of copolymers decreased. When Ti/(Bt+He) and reaction time increased, the insoluble content in CHCl of copolymers also increased. The crystallization and stereoregularity of poly(1-butene) decreased with the addition of He.

关键词： reaction     conversion     temperature     polymerization temperature     magnetic resonance    

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参与中文配对词语联想学习记忆的脑区和神经机制——脑功能磁共振的研究

郑金龙,舒斯云,刘颂豪,郭周义,吴永明,包新民, 张增强,金梅,马翰章

《中国工程科学》 2008年 第10卷 第5期   页码 38-45

摘要：

通过脑功能磁共振技术，研究健康人参与语言的词语配对联想学习记忆任务的脑区和神经机制。对16名右利手健康志愿者进行一项词语配对联想学习记忆任务作业的同时，进行脑功能磁共振扫描。实验采用组块设计，实验任务（包括记忆编码相和记忆提取相）与对照任务（共两个相）交替进行；数据采用SPM99软件进行数据分析和脑功能区定位。结果表明：左侧额叶，特别是左侧额叶的额中下回和枕叶的18，19区在词语联想学习记忆的编码阶段中起重要作用；而左侧顶上小叶、缘上回和角回则在进行记忆提取阶段起重要作用；左侧纹状体边缘区参与了人脑词语联想学习记忆作业的编码阶段。揭示了人大脑完成语言联想学习记忆任务时，除额、顶、枕和颞叶的皮层结构参与外，还新发现有皮层下结构如纹状体参与了词语联想学习记忆。在配对词语的编码和提取阶段，激活的脑区有所变化，显示了这两个语言阶段的神经活动变化机制。

关键词： 人脑功能磁共振     配对词语     语言     联想学习记忆     皮层和皮层下结构    

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High-intensity focused ultrasound tumor ablation: Review of ten years of clinical experience

Lian ZHANG, Zhi-Biao WANG

《医学前沿（英文）》 2010年 第4卷 第3期   页码 294-302 doi: 10.1007/s11684-010-0092-8

摘要： High-intensity focused ultrasound (HIFU) is a technique to destroy tissue at depth within the body, selectively and without harming overlying and adjacent structures within the path of the beam because the ultrasonic intensity at the beam focus is much higher than that outside of the focus. Diagnostic ultrasound is the first imaging modality used for guiding HIFU ablation. In 1997, a patient with osteosarcoma was first successfully treated with ultrasound imaging-guided HIFU in Chongqing, China. Over the last decade, thousands of patients with uterine fibroids, liver cancer, breast cancer, pancreatic cancer, bone tumors, and renal cancer have been treated with ultrasound imaging-guided HIFU. Based on several research groups’ reports, as well as our ten-year clinical experience, we conclude that this technique is safe and effective in treating human solid tumors. HIFU is a promising technique. Most importantly, HIFU offers patients another alternative when those patients have no other treatment available.

关键词： high-intensity focused ultrasound (HIFU)     ultrasound imaging-guided HIFU (USgHIFU)     magnetic resonance imaging-guided HIFU (MRgHIFU)    

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chloride diffusion coefficient and microstructure parameters in concrete: A comparative analysis using NMR

Yurong ZHANG, Shengxuan XU, Yanhong GAO, Jie GUO, Yinghui CAO, Junzhi ZHANG

《结构与土木工程前沿（英文）》 2020年 第14卷 第6期   页码 1509-1519 doi: 10.1007/s11709-020-0681-9

摘要： Permeability is a major indicator of concrete durability, and depends primarily on the microstructure characteristics of concrete, including its porosity and pore size distribution. In this study, a variety of concrete samples were prepared to investigate their microstructure characteristics via nuclear magnetic resonance (NMR), mercury intrusion porosimetry (MIP), and X-ray computed tomography (X-CT). Furthermore, the chloride diffusion coefficient of concrete was measured to explore its correlation with the microstructure of the concrete samples. Results show that the proportion of pores with diameters<1000 nm obtained by NMR exceeds that obtained by MIP, although the difference in the total porosity determined by both methods is minimal. X-CT measurements obtained a relatively small porosity; however, this likely reflects the distribution of large pores more accurately. A strong correlation is observed between the chloride diffusion coefficient and the porosity or contributive porosity of pores with sizes<1000 nm. Moreover, microstructure parameters measured via NMR reveal a lower correlation coefficient versus the chloride diffusion coefficient relative to the parameters determined via MIP, as NMR can measure non-connected as well as connected pores. In addition, when analyzing pores with sizes>50 µm, X-CT obtains the maximal contributive porosity, followed by MIP and NMR.

关键词： permeability     microstructure     NMR     MIP     X-CT    

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Solid-state NMR for metal-containing zeolites: From active sites to reaction mechanism

Xingling Zhao, Jun Xu, Feng Deng

《化学科学与工程前沿（英文）》 2020年 第14卷 第2期   页码 159-187 doi: 10.1007/s11705-019-1885-1

摘要： Metal-containing zeolite catalysts have found a wide range of applications in heterogeneous catalysis. To understand the nature of metal active sites and the reaction mechanism over such catalysts is of great importance for the establishment of structure-activity relationship. The advanced solid-state NMR (SSNMR) spectroscopy is robust in the study of zeolites and zeolite-catalyzed reactions. In this review, we summarize recent developments and applications of SSNMR for exploring the structure and property of active sites in metal-containing zeolites. Moreover, detailed information on host-guest interactions in the relevant zeolite catalysis obtained by SSNMR is also discussed. Finally, we highlight the mechanistic understanding of catalytic reactions on metal-containing zeolites based on the observation of key surface species and active intermediates.

关键词： metal-containing zeolites     solid-state NMR     active site     host-guest interaction     reaction mechanism    

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Modeling and analysis of magnetic dipoles in weak magnetic field

WANG Zhaoxia, ZHANG Weimin, LIU Hongguang

《机械工程前沿（英文）》 2008年 第3卷 第2期   页码 222-225 doi: 10.1007/s11465-008-0028-z

摘要： The magnetic leakage field distribution resulting from linear defects of a tube sample in the geomagnetic field is modeled according to the magnetic dipole theory. The formula to compute the normal component of the weak magnetic field is deduced based on the spatial distribution of the magnetic dipole. The shape and characteristics of the zero line (an important criterion for magnetic memory testing) of the normal field is analyzed under different longitudinal magnetizations. Results show that the characteristics of the zero line should be considered when the metal magnetic memory testing method is used to find and locate the defect.

关键词： geomagnetic     theory     important criterion     magnetic leakage     normal component    

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Multi-harmonic forced vibration and resonance of simple beams to moving vehicles

《结构与土木工程前沿（英文）》   页码 981-993 doi: 10.1007/s11709-023-0979-5

摘要： This study modeled the moving-vehicle-induced forcing excitation on a single-span prismatic bridge as a multiple frequency-multiplication harmonic load on the modal coordinates of a linear elastic simple Euler–Bernoulli beam, and investigated the forced modal oscillation and resonance behavior of this type of dynamic system. The forced modal responses consist of multiple frequency-multiplication steady-state harmonics and one damped mono-frequency complementary harmonic. The analysis revealed that a moving load induces high-harmonic forced resonance amplification when the moving speed is low. To verify the occurrence of high-harmonic forced resonance, numerical tests were conducted on single-span simple beams based on structural modeling using the finite element method (FEM) and a moving sprung-mass oscillator vehicle model. The forced resonance amplification characteristics of the fundamental mode for beam response estimation are presented with consideration to different end restraint conditions. The results reveal that the high-harmonic forced resonance may be significant for the investigated beams subjected to vehicle loads moving at specific low speeds. For the investigated single-span simple beams, the moving vehicle carriage heaving oscillation modulates the beam modal frequency, but does not induce notable variation of the modal oscillation harmonic structure for the cases that vehicle of small mass moves in low speed.

关键词： forced vibration     linear Euler beam     moving load     harmonic structure     frequency modulation     end restraints    

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Sectional model test study on vortex-excited resonance of vehicle-bridge system of Shanghai Bridge over

Li ZHOU, Yaojun GE

《结构与土木工程前沿（英文）》 2009年 第3卷 第1期   页码 67-72 doi: 10.1007/s11709-009-0007-4

摘要： It is necessary to study how vehicles influence the vortex-excited resonance of vehicle-bridge systems, because lock-in wind speed is low and vortex-excited resonance is sensitive to any change in the main girder sections. Based on the Shanghai Bridge over the Yangtse River, the vortex-excited resonance of a 1∶60 scale sectional model was tested in a TJ-1wind tunnel, with or without vehicles at the attack angle of 0°, +3 and -3°, respectively. The conversion relationships between the resonant amplitudes of the sectional model and that of the prototype bridge were also established by mode shape correction. The result indicates that: 1) for the bridge with vehicles, the vertical vortex-excited resonance is accompanied by torsion vibration with the same frequency, and vice versa, 2) the amplitude of vortex-excited resonance of the bridge with vehicles is much larger than that of the bridge without vehicles, and 3) the lock-in wind speed of the vortex-excited resonance becomes smaller due to the disturbance of vehicles. It is obvious that vehicles bring about changes in the aerodynamic shape of the main girder. Therefore, the influence of vehicles on vortex-excited resonance performance of vehicle-bridge systems, in terms of both amplitude and mode, should not be ignored.

关键词： vehicle-bridge system     sectional mode     vortex-excited resonance     wind tunnel test     mode shape correction    

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Extended stochastic resonance (SR) and its applications in weak mechanical signal processing

Niaoqing HU, Min CHEN, Guojun QIN, Lurui XIA, Zhongyin PAN, Zhanhui FENG,

《机械工程前沿（英文）》 2009年 第4卷 第4期   页码 450-461 doi: 10.1007/s11465-009-0072-3

摘要： To catch symptoms of machine failure as early as possible, one of the most important strategies is to apply more progressive techniques during signal processing. This paper presents a method based on stochastic resonance (SR) to detect weak fault signal. First, a discrete model of a bistable system that can demonstrate SR is researched, and the stability condition for controlling the selection of model parameters of the discrete model and guarantee the solving convergence are established. Then, the frequency range of the weak signals that the SR model can detect is extended through a type of normalized scale transformation. Finally, the method is applied to extract the weak characteristic component from heavy noise to indicate the little crack fault in a bearing outer circle.

关键词： extended stochastic resonance (SR)     stability analysis of SR     scale transform     weak signal detection     incipient fault detection     envelope analysis    

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标题 作者 时间 类型 操作

Metabolomics in human type 2 diabetes research

null

期刊论文

Application and mechanism of polysaccharide extracted from Enteromorpha to remove nano-ZnO and humic acid in coagulation process

Jianzhang Sun, Baoyu Gao, Yuanxia Luo, Moxi Xue, Xing Xu, Qinyan Yue, Yan Wang

期刊论文

Discovery of the mechanisms of acupuncture in the treatment of migraine based on functional magneticresonance imaging and omics

期刊论文

Machine learning for detecting mesial temporal lobe epilepsy by structural and functional neuroimaging

Baiwan Zhou, Dongmei An, Fenglai Xiao, Running Niu, Wenbin Li, Wei Li, Xin Tong, Graham J Kemp, Dong Zhou, Qiyong Gong, Du Lei

期刊论文

全氟化碳乳剂19F磁共振成像的最新进展

Anne H. Schmieder,Shelton D. Caruthers,Jochen Keupp,Samuel A. Wickline,Gregory M. Lanza

期刊论文

Progress in NMR-based metabolomics of

Qifang PAN,Jingya ZHAO,Yuliang WANG,Kexuan TANG

期刊论文

Copolymerization of 1-butene and 1-hexene with supported titanium catalyst

ZHAO Yongxian, SHAO Huafeng, WANG Bo, YAO Wei, HUANG Baochen

期刊论文

参与中文配对词语联想学习记忆的脑区和神经机制——脑功能磁共振的研究

郑金龙,舒斯云,刘颂豪,郭周义,吴永明,包新民, 张增强,金梅,马翰章

期刊论文

High-intensity focused ultrasound tumor ablation: Review of ten years of clinical experience

Lian ZHANG, Zhi-Biao WANG

期刊论文

chloride diffusion coefficient and microstructure parameters in concrete: A comparative analysis using NMR

Yurong ZHANG, Shengxuan XU, Yanhong GAO, Jie GUO, Yinghui CAO, Junzhi ZHANG

期刊论文

Solid-state NMR for metal-containing zeolites: From active sites to reaction mechanism

Xingling Zhao, Jun Xu, Feng Deng

期刊论文

Modeling and analysis of magnetic dipoles in weak magnetic field

WANG Zhaoxia, ZHANG Weimin, LIU Hongguang

期刊论文

Multi-harmonic forced vibration and resonance of simple beams to moving vehicles

期刊论文

Sectional model test study on vortex-excited resonance of vehicle-bridge system of Shanghai Bridge over

Li ZHOU, Yaojun GE

期刊论文

Extended stochastic resonance (SR) and its applications in weak mechanical signal processing

Niaoqing HU, Min CHEN, Guojun QIN, Lurui XIA, Zhongyin PAN, Zhanhui FENG,

期刊论文