TALANTA
·
2024
·
IF 5.6
Al-Fakih Ali Mohammed,Chaohong Feng,Ting Jiang,Wei Xu
Miniaturized mass spectrometers, with their increasing portability and performance enhancements, play a crucial role in selectively analyzing target compounds within complex mixtures, particularly in situ environments. As part of our ongoing efforts to enhance the analytical capabilities of the custom-built "brick" mass spectrometer, this study compared and optimized methods for ion isolation using Stored Waveform Inverse Fourier Transform (SWIFT) and Grid-SWIFT waveforms. The efficacy of the SWIFT and Grid-SWIFT waveforms in selective ion isolation was investigated, and through optimization of both waveforms, improved ion isolation efficiency, and peak resolution were demonstrated by adjusting waveform duration and amplitude. The results conclusively showed that Grid-SWIFT outperforms traditional SWIFT waveforms in enhancing the isolation of target ions. Additionally, a novel simulation-based approach was developed to simulate the behavior of ion trajectories under the SWIFT and Grid-SWIFT waveforms within LIT to provide a theoretical basis for better performance of the Grid-SWIFT waveforms. Results show that longer waveform durations help reduce energy leakage, providing higher isolation efficiency. Grid-SWIFT waveforms exhibited significantly less energy leakage compared to SWIFT waveforms. Consequently, using Grid-SWIFT as isolation waveforms improved the mass spectra' intensity and resolution.
研究领域:
分析化学
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质谱技术
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仪器科学与技术
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产品关联
DOI
PubMed
高影响因子
VETERINARY MICROBIOLOGY
·
2024
·
IF 2.4
Guangbin Bao,Shinuo Fan,Chunyan Hu,Chen Li,Fei Ma,Guijun Wang,Hongjie Fan,Qing Wang
Duck Tembusu virus (DTMUV) is a newly emerging pathogen that causes massive economic losses to the poultry industry in China and neighbouring countries. Vimentin, an intermediate filament protein, has been demonstrated to be involved in viral replication during infection. However, the specific role of vimentin in DTMUV replication has not been determined. In this study, we found that overexpression of vimentin in BHK-21 cells can inhibit DTMUV replication. Moreover, DTMUV replication was enhanced after vimentin expression was reduced in BHK-21 cells via small interfering RNA (siRNA). Further research indicated that DTMUV infection had no effect on the transcription or expression of vimentin. However, we found that DTMUV infection induced vimentin rearrangement, and the rearrangement of vimentin was subsequently confirmed to negatively modulate viral replication through the use of a vimentin network disrupting agent. Vimentin rearrangement is closely associated with its phosphorylation. Our experiments revealed that the phosphorylation of vimentin at Ser56 was promoted in the early stage of DTMUV infection. In addition, by inhibiting the phosphorylation of vimentin at Ser56 with a CDK5 inhibitor, vimentin rearrangement was suppressed, and DTMUV replication was significantly enhanced. These results indicated that DTMUV infection induced vimentin phosphorylation and rearrangement through CDK5, resulting in the inhibition of DTMUV replication. In summary, our study reveals a role for vimentin as a negative factor in the process of DTMUV replication, which helps to elucidate the function of cellular proteins in regulating DTMUV replication.
研究领域:
病毒学
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细胞生物学
·
分子生物学
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产品关联
DOI
PubMed
高影响因子
ANALYTICAL CHEMISTRY
·
2024
·
IF 6.7
Ang Li,Jian Sun,Haoqiang Yan,Dayu Li,Wei Xu
In miniature ion trap mass spectrometry, achieving a balance between isolation resolution and efficiency is a formidable challenge. The presence of absorption curves causes target ions to inadvertently absorb energy from AC signal components near their resonant frequencies. To mitigate this issue, SAM–SFM waveforms introduce a parameter known as the decreasing factor. Unlike SWIFT waveforms, SAM–SFM’s spectral profile intentionally departs from a rectangular window, adopting an arch-shaped excitation window to minimize the impact on target ions and improve ion isolation efficiency. SAM–SFM waveforms have the advantage of low computational complexity, enabling real-time computation using an embedded FPGA technology. Regardless of any parameter changes, the FPGA can consistently guarantee waveform output within 1 μs. This not only enhances throughput but also eliminates the need for a PC in miniature mass spectrometry devices. The performance of SAM–SFM has been validated on an improved “Brick” miniature ion trap mass spectrometer. Comparative experiments with SWIFT waveforms confirm the lossless unit-mass isolation capabilities of SAM–SFM. This waveform has the capability to simultaneously isolate multiple target ions, even allowing for the lossless isolation of ions with lower abundance within isotopic clusters, albeit at the cost of requiring extended isolation durations.
研究领域:
分析化学
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质谱技术
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仪器科学与技术
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产品关联
DOI
PubMed
高影响因子
COMPOSITES PART B-ENGINEERING
·
2021
·
IF 9.078
Qian Zhang,Liang Shen,Ping Liu,Panpan Xia,Junliang Li,Han Feng,Caixia Liu,Kun Xing,Aiguo Song,Man Li,Xiaoming Yang,Ying Huang
Blood pressure is an important parameter of a heart-pumping function, vascular peripheral resistance, and blood volume in human body. The non-invasive blood pressure measurement method has attracted tremendous attention due to its advantages of simple operation and comfort. In this paper, graft-modified MWCNTs and water-based polyurethane are used as filler and matrix, which are combined with simple dipping process to produce a resistance-type flexible pressure sensor with crack structure. The sensor with crack structure exhibits a high gauge factor (∼1582.7), fast response time (∼58 ms) and good repeatability (>2000 cycles) under 0–5% strain. By attaching the sensor to the radial artery of human wrist, the pulse waveform is accurately captured. By adopting the time-domain analysis method, in addition to the fast Fourier transform and threshold method which is employed to position and extract the characteristic value of pulse signal, a three-layer back propagation neural network is constructed to regress blood pressure value. The correlation coefficients of systolic blood pressure, diastolic blood pressure and mean blood pressure were 0.950, 0.875 and 0.947, respectively, which could meet the A-level standards of British Hypertension Society and Association for the Advancement of Medical Instrumentation. This study provides a good real-time and portable technology for home blood pressure measurement.
研究领域:
医学工程
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生物医学
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产品关联
DOI
高影响因子
AICHE JOURNAL
·
2022
·Vol. 68
·期 8
·e17689
·
IF 4.167
Qiang Zhang,Zhengya Dong,Zhikai Liu,Guangwen Chen
This study aims to investigate the effect of ultrasonic waveforms on the gas–liquid mass transfer process. For a given load power ( P ), continuous rectangular wave yielded stronger bubble oscillation and higher mass transfer coefficient ( k L a ) than continuous triangular and sinusoidal wave. For pulsed ultrasound, the k L a decreased monotonically with decreasing duty ratio ( D ), resulting in weak enhancement at low D (≤33%). For a given average load power ( P A ), concentrating the P for a shorter period resulted in a higher k L a due to stronger cavitation behavior. For a given P A and D , decreasing the pulse period ( T ) led to an increase in k L a , which reached a constant high level when the T fell below a critical value. By optimizing the D and T , a k L a equivalent to 92% of that under continuous ultrasound was obtained under pulsed ultrasound at a D of 67%, saving 33% in power consumption.
研究领域:
化学工程
·
声化学
·
传质学
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产品关联
DOI
高影响因子
PHARMACOLOGICAL RESEARCH
·
2022
·
IF 10.334
Qing Li,Meng-Sheng Deng,Ren-Tao Wang,Hao Luo,Yuan-Yuan Luo,Dong-Dong Zhang,Kui-Jun Chen,Xiao-Fu Cao,Guang-Ming Yang,Tie-Mei Zhao,Bo Xu,Cheng-Xiong Xu,Jian-Min Wang
Idiopathic pulmonary fibrosis (IPF) is a progressive disease with high mortality and limited therapeutic options. The immune checkpoint PD1/PD-L1 axis is related to the pathogenesis of pulmonary fibrosis, and upregulated expression levels of PD-L1 have been demonstrated in IPF patients. However, the mechanism of PD-L1 in pulmonary fibrosis is not fully understood. Here, we demonstrated upregulated expression of PD-L1 in fibrotic lung tissues and sera of IPF patients. Bleomycin (BLM) treatment induced PD-L1 upregulation, EMT (Epithelial-Mesenchymal Transition) and fibrosis-like morphology changes in human pulmonary alveolar epithelial cells (HPAEpiCs). Silencing PD-L1 attenuated BLM-induced EMT and fibrosis-like morphology changes in HPAEpiCs. In addition, we identified that PD-L1 directly binds to vimentin and inhibits vimentin ubiquitination, thereby increasing vimentin levels in HPAEpiCs. Silencing of vimentin inhibited BLM- and PD-L1-induced fibrosis in HPAEpiCs. The correlation between PD-L1 and EMT or vimentin expression was further confirmed in clinical samples and animal models. Finally, we used BLM- and paraquat-induced pulmonary fibrosis animal models to confirm the anti-pulmonary fibrosis effects of PD-L1 silencing. Taken together, our findings suggest that upregulated PD-L1 stimulates EMT of alveolar epithelial cells by increasing vimentin levels by inhibiting vimentin ubiquitination, thereby contributing to pulmonary fibrosis.
研究领域:
呼吸病学
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免疫学
·
细胞生物学
✓ 已验证
DOI
PubMed
高影响因子
ANALYTICAL CHEMISTRY
·
2019
·
IF 6.35
Zuqiang Xu,Ting Jiang,Qian Xu,Yanbing Zhai,Dayu Li,Wei Xu
Besides portability and increasingly improved performances, the ability of screening target analyte from complex compounds is a crucial function of miniature mass spectrometers, especially for in situ analysis. Selected reaction monitoring (SRM) and multiple reaction monitoring (MRM) operation modes are the most widely used mass spectrometry operation methods for target analyte quantitation. As a continuous effort to improve the analytical performances of the “brick” mass spectrometer, built in-house, pseudo-SRM and pseudo-MRM modes were realized on the linear ion trap mass analyzer in the device. A broadband excitation waveform in both time and frequency domains, namely, the Grid-SWIFT waveform, was constructed and compared with the conventional SWIFT waveform. By isolating target ions during the ion introduction period using the Grid-SWIFT waveform, target ions could be efficiently accumulated inside the ion trap without experiencing space charge effects and interferences from nontarget ions in the samples. As a result, not only the detection sensitivity of the target analyte could be increased, but also the quantitation accuracy over a relatively wide concentration range could be improved.
研究领域:
分析化学
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质谱分析
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仪器科学与技术
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY
·
2016
·
IF 3.031
Fuxing Xu,Qiankun Dang,Xinhua Dai,Xiang Fang,Yuanyuan Wang,Li Ding,Chuan-Fan Ding
Collision induced dissociation (CID) is one of the most established techniques for tandem mass spectrometry analysis. The CID of mass selected ion could be realized by ion resonance excitation with a digital rectangular waveform. The method is simple, and highly efficient CID result could be obtained by optimizing the experimental parameters, such as digital waveform voltage, frequency, and q value. In this work, the relationship between ion trapping waveform voltage and frequency at preselected q value, the relationship between waveform frequency and the q value at certain ion trapping voltage for optimum CID efficiency were investigated. Experiment results showed that the max CID efficiency of precursor reserpine ions can be obtained at different trapping waveform voltage and frequency when q and β are different. Based on systematic experimental analysis, the optimum experimental conditions for high CID efficiency can be calculated at any selected β or q. By using digital ion trap technology, the CID process and efficient fragmentation of parent ions can be realized by simply changing the trapping waveform amplitude, frequency, and the β values in the digital ion trap mass spectrometry. The technology and method are simple. It has potential use in ion trap mass spectrometry.
研究领域:
分析化学
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质谱学
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产品关联
DOI
PubMed
高影响因子
Chemosensors
·
2022
·Vol. 10
·期 6
·226
·
IF 4.229
Xue Shi,Hua Zhang,Hanyang Ji,Fanli Meng
Volatile organic compounds (VOC) harm human health seriously in the air. Therefore, it is essential to recognize VOC gases qualitatively and quantitatively. The dynamic measurement method can improve the selectivity of metal oxide semiconductor (MOS) gas sensors to VOC, but there is a problem of the insufficient number of characteristic peaks. From the experimental point of view, the primary judgment basis for the correct qualitative and quantitative recognition of VOC gases by the dynamic measurement method is the characteristic peak of the dynamic response signal. However, the traditional dynamic measurement method generally only has two characteristic peaks. In this experiment, the voltage was changed at the time of the second characteristic peak by controlling the constant dynamic response period. Taking ethyl alcohol as an example, the experimental results show that the characteristic peak of the dynamic response signal does not increase when the voltage is constant. However, a new characteristic peak will appear based on a continuously rising heating voltage. The characteristic peaks of the dynamic response of n-propyl alcohol, isopropyl alcohol, and n-butyl alcohol were also increased based on the rising heating voltage waveform. Based on the K-Nearest-Neighbors algorithm, the qualitative and quantitative recognition rate of the four alcohol homologue gases reached 100%.Keywords:dynamic response signal;characteristic peaks;ZnO gas sensor;periodic cycle heating waveform;alcohol homologue gases
研究领域:
传感器技术
·
环境科学
·
材料科学
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产品关联
DOI
高影响因子
Innovative Food Science & Emerging Technologies
·
2025
·
IF 6.8
Liuxia Li,Yifan Gao,Zihuang Peng,Xun Pei,Ruorong Hua,Fuchang Lin,Rui Zhang,Yi Liu
The influence of pulsed electric fields with different waveforms on extracting valuable compounds from microalgae was investigated. Four different waveforms (rectangle, bipolar rectangle, oscillating superimposed rectangle, and two-step rectangle) with the same amplitude (25 kV/cm) and energy (4 J/pulse) were generated using a pulsed power generator to induce electroporation and component release of three species of microalgae. For Nannochloropsis and Spirulina platensis , the oscillating superimposed rectangular pulse increased the conductivity of microalgal suspensions twice as much as the other waveforms. For Chlorella vulgaris , the protein extraction effect of the oscillating superimposed rectangular pulse was 70 % higher than that of the conventional unipolar rectangular pulse. The pulse waveforms did not show significant differences in the extraction of small molecules, with the carbohydrate extraction index exceeding 0.3 for four waveforms. The results showed that the pulse waveforms were important for extracting large molecules (e.g., proteins). Reasonably designed pulse waveforms for different species of microalgae can significantly improve protein extraction or selectively extract carbohydrates.
研究领域:
生物技术
·
生物工程
·
应用微生物学
·
食品科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
LANGMUIR
·
2020
·
IF 3.557
Yiqun Wang,Yuan Yao
In natural tissue, nanofibrils in extracellular matrix (ECM), such as collagen fibrils, direct cell migration through contacting guidance. The contacting nanofibers on cell-ECM interface are reorganized from curl fibers to straightened fibers. However, how these nanofibers regulate single cell migration remains obscure. To investigate this issue, we fabricated collagen/polymer based biomimetic nanofiber sheets of varying topography. And we selected tumorigenic cell KGN and nontumorigenic cell 293T for comparison. We found KGN showed higher sensitivity to the nanofiber alignment rather than the nontumorigenic cell 293T, in morphological change, trajectory adaptation, and velocity variation. We also found aligned nanofibers shaped both KGN and 293T into elongated spindle morphology. Comparatively, KGN had greater perimeter and lower roundness than 293T. To study the dynamics of single cell migration of KGN and 293T, we conducted trajectory tracking and siRNA validation on regulatory proteins. We found nanofibers of varying topography regulated the patterns of single cell migration differently. For KGN cell, β-catenin, Rac1, and Cdc42 participated in its directional migration, but it was impervious to vimentin. Comparatively, epithelial cell 293T involved vimentin in its directional migration.
研究领域:
生物材料
·
细胞生物学
·
组织工程
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产品关联
DOI
PubMed
高影响因子
Nanoscale
·
2020
·Vol. 12
·期 5
·3183-3193
·
IF 6.895
Yiqun Wang,Jinkang Gong,Yuan Yao
Extracellular matrix anisotropy tunes the organization and movement of surrounding cells. The primary mediators of the extracellular matrix are fiber-based materials. Natural collagen fibers reorganize from curled and isotropic fibers to straightened and anisotropic fibers during tumorigenesis, yet how the cytoskeleton is involved in the directional migration in response to the topography is unknown. To investigate this, we fabricated random, orthogonal, and aligned nanofibers to deconstruct the basic mechanisms for the migration of the human pancreatic cancer cells PANC-1 on different substrates. We found that the extracellular matrix orchestrated actin reorganization by templating the surface topography as an irregular pattern on random fibers, crossover feature on orthogonal fibers, and parallel characteristics on aligned fibers. The intermediate filament as vimentin was upregulated to form a perinuclear shape on orthogonal or aligned surfaces. We also found that the nanofiber topography mediated the directional migration via different mechanisms. The directionality ratio and velocity were statistically analyzed to unveil the pattern of directional migration. Cells on aligned nanofibers yielded a greater velocity. Rac1 and Cdc42 were involved in cell migration through regulating actin polymerization and membrane protrusions. Thus, our findings elucidate that nanofiber alignment orchestrates cytoskeletal reorganization and mediates the directional migration of cancer cells.
研究领域:
细胞生物学
·
癌症生物学
·
生物物理学
·
组织工程
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产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）