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Burke SE, Auvil ZA, Hanold KA, Continetti RE. Detection of intact amino acids with a hypervelocity ice grain impact mass spectrometer. Proc Natl Acad Sci U S A 2023; 120:e2313447120. [PMID: 38048472 PMCID: PMC10723046 DOI: 10.1073/pnas.2313447120] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2023] [Accepted: 10/23/2023] [Indexed: 12/06/2023] Open
Abstract
Astrobiology studies are a top priority in answering one of the most fundamental questions in planetary science: Is there life beyond Earth? Saturn's icy moon Enceladus is a prime target in the search for life in our solar system, identified by NASA as the second-highest priority site for a flagship mission in the next decade. The orbital sampling technique of impact ionization mass spectrometry indicated the presence of complex organics in the small icy plume particles ejected by Enceladus encountered previously by Cassini. However, high interaction velocities caused ambiguity as to the origin and identity of the organics. Laboratory validation of this technique is needed to show that biosignature molecules can survive an impact at hypervelocity speeds for detection. Here, we present results on the hypervelocity impact of organic-laden submicron ice grains for in situ mass spectrometric characterization with the first technique to accurately replicate this plume sampling scenario: the Hypervelocity Ice Grain Impact Mass Spectrometer. Our results show good agreement with Cassini data at comparable compositions. We show that amino acids entrained in ice grains can be detected intact after impact at speeds up to 4.2 km/s and that salt reduces their detectability, validating the predictions from other model systems. Our results provide a benchmark for this orbital sampling method to successfully detect signs of life and for the interpretation of past and future data. This work has implications not only for a potential Enceladus mission but also for the forthcoming Europa Clipper mission.
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Affiliation(s)
- Sally E. Burke
- Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, CA92093-0340
| | - Zachary A. Auvil
- Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, CA92093-0340
| | - Karl A. Hanold
- Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, CA92093-0340
| | - Robert E. Continetti
- Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, CA92093-0340
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2
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Marcus D, Phelps DL, Savage A, Balog J, Kudo H, Dina R, Bodai Z, Rosini F, Ip J, Amgheib A, Abda J, Manoli E, McKenzie J, Yazbek J, Takats Z, Ghaem-Maghami S. Point-of-Care Diagnosis of Endometrial Cancer Using the Surgical Intelligent Knife (iKnife)-A Prospective Pilot Study of Diagnostic Accuracy. Cancers (Basel) 2022; 14:5892. [PMID: 36497372 PMCID: PMC9736036 DOI: 10.3390/cancers14235892] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Revised: 11/25/2022] [Accepted: 11/26/2022] [Indexed: 12/03/2022] Open
Abstract
Introduction: Delays in the diagnosis and treatment of endometrial cancer negatively impact patient survival. The aim of this study was to establish whether rapid evaporative ionisation mass spectrometry using the iKnife can accurately distinguish between normal and malignant endometrial biopsy tissue samples in real time, enabling point-of-care (POC) diagnoses. Methods: Pipelle biopsy samples were obtained from consecutive women needing biopsies for clinical reasons. A Waters G2-XS Xevo Q-Tof mass spectrometer was used in conjunction with a modified handheld diathermy (collectively called the 'iKnife'). Each tissue sample was processed with diathermy, and the resultant surgical aerosol containing ionic lipid species was then analysed, producing spectra. Principal component analyses and linear discriminant analyses were performed to determine variance in spectral signatures. Leave-one-patient-out cross-validation was used to test the diagnostic accuracy. Results: One hundred and fifty patients provided Pipelle biopsy samples (85 normal, 59 malignant, 4 hyperplasia and 2 insufficient), yielding 453 spectra. The iKnife differentiated between normal and malignant endometrial tissues on the basis of differential phospholipid spectra. Cross-validation revealed a diagnostic accuracy of 89% with sensitivity, specificity, positive predictive value and negative predictive value of 85%, 93%, 94% and 85%, respectively. Conclusions: This study is the first to use the iKnife to identify cancer in endometrial Pipelle biopsy samples. These results are highly encouraging and suggest that the iKnife could be used in the clinic to provide a POC diagnosis.
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Affiliation(s)
- Diana Marcus
- Department of Surgery and Cancer, Imperial College London, Du Cane Road, London W12 0NN, UK
| | - David L. Phelps
- Department of Gynaecological Oncology, University Hospital Southampton, Coxford Road, Southampton SO16 5YA, UK
| | - Adele Savage
- Department of Surgery and Cancer, Imperial College London, Du Cane Road, London W12 0NN, UK
| | - Julia Balog
- Department of Metabolism, Digestion and Reproduction, Imperial College London, Du Cane Road, London W12 0NN, UK
| | - Hiromi Kudo
- Centre for Pathology, Imperial College London, 4th Floor Clarence Wing, St Mary’s Hospital, London W2 1NY, UK
| | - Roberto Dina
- Department of Surgery and Cancer, Imperial College London, Du Cane Road, London W12 0NN, UK
| | - Zsolt Bodai
- Department of Metabolism, Digestion and Reproduction, Imperial College London, Du Cane Road, London W12 0NN, UK
| | - Francesca Rosini
- Department of Surgery and Cancer, Imperial College London, Du Cane Road, London W12 0NN, UK
| | - Jacey Ip
- Department of Surgery and Cancer, Imperial College London, Du Cane Road, London W12 0NN, UK
| | - Ala Amgheib
- Department of Surgery and Cancer, Imperial College London, Du Cane Road, London W12 0NN, UK
| | - Julia Abda
- Department of Surgery and Cancer, Imperial College London, Du Cane Road, London W12 0NN, UK
| | - Eftychios Manoli
- Department of Metabolism, Digestion and Reproduction, Imperial College London, Du Cane Road, London W12 0NN, UK
| | - James McKenzie
- Department of Metabolism, Digestion and Reproduction, Imperial College London, Du Cane Road, London W12 0NN, UK
| | - Joseph Yazbek
- Department of Surgery and Cancer, Imperial College London, Du Cane Road, London W12 0NN, UK
| | - Zoltan Takats
- Department of Metabolism, Digestion and Reproduction, Imperial College London, Du Cane Road, London W12 0NN, UK
| | - Sadaf Ghaem-Maghami
- Department of Surgery and Cancer, Imperial College London, Du Cane Road, London W12 0NN, UK
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3
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Foote AP. TECHNICAL NOTE: Analysis of volatile fatty acids in rumen fluid by gas chromatography mass spectrometry using a dimethyl carbonate extraction. J Anim Sci 2022; 100:6602132. [PMID: 35660871 DOI: 10.1093/jas/skac207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2022] [Accepted: 06/01/2022] [Indexed: 11/14/2022] Open
Abstract
Analysis of rumen fluid volatile fatty acids (VFA) is typically conducted by injecting acidified aqueous rumen fluid into a gas chromatograph (GC) with a flame ionization detector (FID). Aqueous samples are highly problematic because of the large vapor volume that can lead to poor peak shape and contamination of inlets, potentially causing sample carryover. Methods using aqueous samples are not well suited for use in a mass spectrometer (MS) detector system. The objective of this project was to validate a dimethyl carbonate (DMC) extraction process and GCMS method for rumen VFA analysis. To perform the extraction, 100 µL of sample, KHSO4 (500 g/L), and 2-ethylbutyrate (internal standard; 8.5 mM) were added to a microcentrifuge tube (in order) followed by 1 mL of DMC. The mixture was thoroughly vortexed, and centrifuged. The organic layer (top) was removed and placed in a GC vial. The DMC extract was injected (0.5 µL) into an Agilent 5977B GCMS (8:1 split injection) with a polar DB-FFAP column. The column was held at 105°C for 5 min, increased at 10°C/min to 150°C, then 65°C/min to 240°C, and held constant for 10 min. The peak area of acetate relative to the internal standard is linear from approximately 2 mM to at least 130 mM and encompasses the expected values of rumen concentrations for the other VFA. Recovery of VFA from spiked rumen fluid was tested at three concentrations in rumen fluid from steers fed a finishing diet or grazing wheat pasture. Recovery was not affected by the diet of the animals (P > 0.10) or the amount of VFA spiked (P > 0.19) for acetate, propionate, isobutyrate, or butyrate. There was an interaction of amount of VFA spiked and the diet of the animal (P = 0.021) for valerate and a tendency for an interaction (P = 0.051) for isovalerate, due to the recovery of the VFA being lower in the medium spike amount in rumen fluid from cattle on wheat pasture. Overall, recovery was greatest for propionate (101.9 ± 1.67%) and lowest for valerate (95.7± 1.95%). Including the 10 min hold at 240°C at the end of each run prevented carryover from sample to sample. This method appears to perform well in a GCMS system and accurately and precisely quantifies rumen fluid VFA.
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Affiliation(s)
- Andrew P Foote
- Department of Animal & Food Sciences, Oklahoma State University, Stillwater, USA
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Guo C, Diao Z, Liu J, Yang B, Zhang J. Quantification and evaluation of ion transmission efficiency in two-stage vacuum chamber miniature mass spectrometer. J Mass Spectrom 2022; 57:e4816. [PMID: 35229406 DOI: 10.1002/jms.4816] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Revised: 01/31/2022] [Accepted: 02/03/2022] [Indexed: 06/14/2023]
Abstract
Miniature mass spectrometer is more compact and portable than traditional commercial mass spectrometry, with more potential for application outside the laboratory. However, a miniature mass spectrometer is less sensitive than a commercial instrument, limiting its application scenarios. The ion transmission efficiency of the instrument is an essential factor affecting the sensitivity. Still, there are few works of literature on the quantitative study of the ion transmission efficiency of each component from a systematic perspective. In this paper, the Faraday cup coupled with a microcurrent signal testing instrument was used to measure the ions generated by nanoelectrospray ionization (nano-ESI), which have successfully gone through several components. Then the ion transmission efficiency of each component was quantified. Results showed that the front lens had the highest ion transmission efficiency of 39.7%, whereas the inlet and skimmer had the lowest ion transfer efficiency of 0.8% and 17.1%. Next, the influence of control parameters on ion transmission efficiency of critical components was investigated. If optimized, the ion funnel and the skimmer had the potential to improve their transmission efficiency by 120% and 79%, respectively. This paper shows the decreasing intensity distribution of ions in the whole transmission process and the transmission efficiency of each component, which can guide for improving the sensitivity of the miniature mass spectrometer.
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Affiliation(s)
- Chengan Guo
- Shenzhen Chin Instrument Co., Ltd., Shenzhen, China
- Tsinghua Shenzhen International Graduate School, Shenzhen, China
| | - Zhaoyin Diao
- Suzhou Fortune Precision Instrument Co., Ltd., Suzhou, China
| | - Jianli Liu
- School of Life Science, Beijing Institute of Technology, Beijing, China
| | - Baokun Yang
- School of Life Science, Beijing Institute of Technology, Beijing, China
| | - Jian Zhang
- School of Life Science, Beijing Institute of Technology, Beijing, China
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Sasaki Y, Zhu J, Shi Y, Gu W, Kobe B, Ve T, DiAntonio A, Milbrandt J. Nicotinic acid mononucleotide is an allosteric SARM1 inhibitor promoting axonal protection. Exp Neurol 2021; 345:113842. [PMID: 34403688 PMCID: PMC8571713 DOI: 10.1016/j.expneurol.2021.113842] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Revised: 08/09/2021] [Accepted: 08/12/2021] [Indexed: 12/31/2022]
Abstract
SARM1 is an inducible NAD+ hydrolase that is the central executioner of pathological axon loss. Recently, we elucidated the molecular mechanism of SARM1 activation, demonstrating that SARM1 is a metabolic sensor regulated by the levels of NAD+ and its precursor, nicotinamide mononucleotide (NMN), via their competitive binding to an allosteric site within the SARM1 N-terminal ARM domain. In healthy neurons with abundant NAD+, binding of NAD+ blocks access of NMN to this allosteric site. However, with injury or disease the levels of the NAD+ biosynthetic enzyme NMNAT2 drop, increasing the NMN/ NAD+ ratio and thereby promoting NMN binding to the SARM1 allosteric site, which in turn induces a conformational change activating the SARM1 NAD+ hydrolase. Hence, NAD+ metabolites both regulate the activation of SARM1 and, in turn, are regulated by the SARM1 NAD+ hydrolase. This dual upstream and downstream role for NAD+ metabolites in SARM1 function has hindered mechanistic understanding of axoprotective mechanisms that manipulate the NAD+ metabolome. Here we reevaluate two methods that potently block axon degeneration via modulation of NAD+ related metabolites, 1) the administration of the NMN biosynthesis inhibitor FK866 in conjunction with the NAD+ precursor nicotinic acid riboside (NaR) and 2) the neuronal expression of the bacterial enzyme NMN deamidase. We find that these approaches not only lead to a decrease in the levels of the SARM1 activator NMN, but also an increase in the levels of the NAD+ precursor nicotinic acid mononucleotide (NaMN). We show that NaMN inhibits SARM1 activation, and demonstrate that this NaMN-mediated inhibition is important for the long-term axon protection induced by these treatments. Analysis of the NaMN-ARM domain co-crystal structure shows that NaMN competes with NMN for binding to the SARM1 allosteric site and promotes the open, autoinhibited configuration of SARM1 ARM domain. Together, these results demonstrate that the SARM1 allosteric pocket can bind a diverse set of metabolites including NMN, NAD+, and NaMN to monitor cellular NAD+ homeostasis and regulate SARM1 NAD+ hydrolase activity. The relative promiscuity of the allosteric site may enable the development of potent pharmacological inhibitors of SARM1 activation for the treatment of neurodegenerative disorders.
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Affiliation(s)
- Yo Sasaki
- Washington University School of Medicine in Saint Louis, Department of Genetics, St. Louis, MO, USA; Needleman Center for Neurometabolism and Axonal Therapeutics, USA.
| | - Jian Zhu
- Washington University School of Medicine in Saint Louis, Department of Genetics, St. Louis, MO, USA; Needleman Center for Neurometabolism and Axonal Therapeutics, USA
| | - Yun Shi
- Institute for Glycomics, Griffith University, Southport, QLD 4222, Australia
| | - Weixi Gu
- School of Chemistry and Molecular Biosciences, Institute for Molecular Bioscience and Australian Infectious Diseases Research Centre, University of Queensland, QLD 4072, Australia
| | - Bostjan Kobe
- School of Chemistry and Molecular Biosciences, Institute for Molecular Bioscience and Australian Infectious Diseases Research Centre, University of Queensland, QLD 4072, Australia
| | - Thomas Ve
- Institute for Glycomics, Griffith University, Southport, QLD 4222, Australia
| | - Aaron DiAntonio
- Washington University School of Medicine in Saint Louis, Department of Developmental Biology, St. Louis, MO, USA; Needleman Center for Neurometabolism and Axonal Therapeutics, USA
| | - Jeffrey Milbrandt
- Washington University School of Medicine in Saint Louis, Department of Genetics, St. Louis, MO, USA; Needleman Center for Neurometabolism and Axonal Therapeutics, USA
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Cho KC, Oh S, Wang Y, Rosenthal LS, Na CH, Zhang H. Evaluation of the Sensitivity and Reproducibility of Targeted Proteomic Analysis Using Data-Independent Acquisition for Serum and Cerebrospinal Fluid Proteins. J Proteome Res 2021; 20:4284-4291. [PMID: 34384221 PMCID: PMC8631582 DOI: 10.1021/acs.jproteome.1c00238] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
There is a need for targeted analysis of biological fluids for diagnosis, prognosis, or monitoring the progression of diseases. Cerebrospinal fluid (CSF) and serum have been widely used for the development of protein analysis for neurodegenerative diseases and other diseases, respectively. Recently, data-independent acquisition (DIA) mass spectrometry (MS) has been developed to increase the throughput over data-dependent acquisition (DDA) on screening of a large number of samples and discovery of candidate targets. When it comes to target validation, the analytical performance of targeted analysis is critical. However, the inter- and intralaboratory analytical performances of the DIA-MS for targeted proteomic analysis of CSF and serum samples have not yet been investigated. In this study, we showed that the DIA-MS approach allowed us to identify and quantify 1732 CSF and 424 serum proteins, with 90% of proteins identified and quantified in at least 50% of DIA-MS runs. To evaluate the sensitivity, linearity, and dynamic range of the DIA approach, we included the stable isotope-labeled (SI) peptides into CSF and serum samples with serial dilutions. The lower limit of quantification (LLOQ) of peptides was 0.1-0.5 fmol, and the dynamic range was over 3.53 orders of magnitude, with excellent linearity (r2 < 0.978) in CSF and serum samples. Finally, the reproducibility of the DIA-MS approach was evaluated using entire proteins identified in CSF and serum samples. The intralaboratory three replicate results showed reliable reproducibility with 12.5 and 17.3% of the median coefficient of variation (CV) in both CSF and serum matrices, whereas the median CVs of interlaboratory three replicates were 23.8 and 32.0% in CSF and serum samples, respectively. The comparison of the quantitative result between replicates showed close similarity at intra- and interlaboratories with a median Pearson correlation value of >0.98 in CSF and serum, respectively. In conclusion, we demonstrate the capability of the DIA approach as a targeted proteomic analysis for candidate proteins from CSF and serum samples.
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Affiliation(s)
- Kyung-Cho Cho
- Department of Pathology, Johns Hopkins University, Baltimore, MD 21231, USA
- These authors contributed equally
| | - Sungtaek Oh
- Departments of Neurology, Johns Hopkins University, Baltimore, MD 21205, USA
- Institute for Cell Engineering, Johns Hopkins University, Baltimore, MD 21205, USA
- These authors contributed equally
| | - Yuefan Wang
- Department of Pathology, Johns Hopkins University, Baltimore, MD 21231, USA
- These authors contributed equally
| | - Liana S. Rosenthal
- Institute for Cell Engineering, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Chan Hyun Na
- Departments of Neurology, Johns Hopkins University, Baltimore, MD 21205, USA
- Institute for Cell Engineering, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Hui Zhang
- Department of Pathology, Johns Hopkins University, Baltimore, MD 21231, USA
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Liu D, Wang S, Zhang J, Xiao W, Miao CH, Konkle BA, Wan XF, Li L. Site-Specific N- and O-Glycosylation Analysis of Human Plasma Fibronectin. Front Chem 2021; 9:691217. [PMID: 34211961 PMCID: PMC8239226 DOI: 10.3389/fchem.2021.691217] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Accepted: 05/21/2021] [Indexed: 11/13/2022] Open
Abstract
Human plasma fibronectin is an adhesive protein that plays a crucial role in wound healing. Many studies had indicated that glycans might mediate the expression and functions of fibronectin, yet a comprehensive understanding of its glycosylation is still missing. Here, we performed a comprehensive N- and O-glycosylation mapping of human plasma fibronectin and quantified the occurrence of each glycoform in a site-specific manner. Intact N-glycopeptides were enriched by zwitterionic hydrophilic interaction chromatography, and N-glycosite sites were localized by the 18O-labeling method. O-glycopeptide enrichment and O-glycosite identification were achieved by an enzyme-assisted site-specific extraction method. An RP–LC–MS/MS system functionalized with collision-induced dissociation and stepped normalized collision energy (sNCE)-HCD tandem mass was applied to analyze the glycoforms of fibronectin. A total of 6 N-glycosites and 53 O-glycosites were identified, which were occupied by 38 N-glycoforms and 16 O-glycoforms, respectively. Furthermore, 77.31% of N-glycans were sialylated, and O-glycosylation was dominated by the sialyl-T antigen. These site-specific glycosylation patterns on human fibronectin can facilitate functional analyses of fibronectin and therapeutics development.
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Affiliation(s)
- Ding Liu
- Department of Chemistry, Georgia State University, Atlanta, GA, United States
| | - Shuaishuai Wang
- Department of Chemistry, Georgia State University, Atlanta, GA, United States
| | - Junping Zhang
- School of Medicine, Indiana University, Indianapolis, IN, United States
| | - Weidong Xiao
- School of Medicine, Indiana University, Indianapolis, IN, United States
| | - Carol H Miao
- Center for Immunity and Immunotherapies, Seattle Children's Research Institute, Seattle, WA, United States
| | | | - Xiu-Feng Wan
- Center for Influenza and Emerging Infectious Diseases, University of Missouri, Columbia, MO, United States.,Department of Molecular Microbiology and Immunology, School of Medicine, University of Missouri, Columbia, MO, United States.,Bond Life Sciences Center, University of Missouri, Columbia, MO, United States.,Department of Electrical Engineering & Computer Science, College of Engineering, University of Missouri, Columbia, MO, United States
| | - Lei Li
- Department of Chemistry, Georgia State University, Atlanta, GA, United States
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Belousov A, Miller M, Continetti R, Madzunkov S, Simcic J, Nikolic D, Maiwald F, Waller S, Malaska M, Cable M. Sampling Accelerated Micron Scale Ice Particles with a Quadrupole Ion Trap Mass Spectrometer. J Am Soc Mass Spectrom 2021; 32:1162-1168. [PMID: 33792296 DOI: 10.1021/jasms.0c00442] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
The Enceladus plume is a target of astrobiological interest in planetary science since it may carry signs of extraterrestrial life entrapped in ice grains formed from the subsurface ocean of this moon of Saturn. Fly-by mission concepts have been proposed to perform close investigations of the plume, including detailed in situ measurements of chemical composition with a new generation of mass spectrometer instrumentation. Such a scenario involves high-velocity collisions (typically around 5 km/s or higher) of the instrument with the encountered ice grains. Postimpact processes may include molecular fragmentation, impact ionization, and various subsequent chemical reactions that could alter the original material prior to analysis. In order to simulate Enceladus plume fly through conditions, we are developing an ice grain accelerator and have coupled it to the quadrupole ion trap mass spectrometer (QITMS) developed for flight applications. Our experimental setup enables the creation and acceleration of ice particles with well-defined size, charge, and velocity, which are subsequently directed into the QITMS, where they impact the surface of the mass analyzer and the analysis of postimpact, volatilized molecules takes place. In this work, we performed mass spectral analysis of ice grains of ca. 1.3 μm in diameter, accelerated and impacted at velocities up to 1000 m/s, with an upgrade of the accelerator in progress that will enable velocities up to 5000 m/s. We report the first observations of ice grain impacts measured by the QITMS, which were recorded as brief increases in the abundance of water molecules detected within the instrument.
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Affiliation(s)
- Anton Belousov
- NASA Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, California 91109, United States
| | - Morgan Miller
- University of California San Diego, Mail Code 0340, 9500 Gilman Drive, La Jolla, California 92093-0340, United States
| | - Robert Continetti
- University of California San Diego, Mail Code 0340, 9500 Gilman Drive, La Jolla, California 92093-0340, United States
| | - Stojan Madzunkov
- NASA Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, California 91109, United States
| | - Jurij Simcic
- NASA Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, California 91109, United States
| | - Dragan Nikolic
- NASA Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, California 91109, United States
| | - Frank Maiwald
- NASA Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, California 91109, United States
| | - Sarah Waller
- NASA Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, California 91109, United States
| | - Michael Malaska
- NASA Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, California 91109, United States
| | - Morgan Cable
- NASA Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, California 91109, United States
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9
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Li X, Li Y, Lawler MJ, Hao J, Smith JN, Jiang J. Composition of Ultrafine Particles in Urban Beijing: Measurement Using a Thermal Desorption Chemical Ionization Mass Spectrometer. Environ Sci Technol 2021; 55:2859-2868. [PMID: 33577293 DOI: 10.1021/acs.est.0c06053] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Ultrafine particles (UFPs) dominate the particle number population in the urban atmosphere and revealing their chemical composition is important. The thermal desorption chemical ionization mass spectrometer (TDCIMS) can semicontinuously measure UFP composition at the molecular level. We modified a TDCIMS and deployed it in urban Beijing. Radioactive materials in the TDCIMS for aerosol charging and chemical ionization were replaced by soft X-ray ionizers so that it can be operated in countries with tight regulations on radioactive materials. Protonated N-methyl-2-pyrrolidone ions were used as the positive reagent ion, which selectively detects ammonia and low-molecular weight-aliphatic amines and amides vaporized from the particle phase. With superoxide as the negative reagent ion, a wide range of inorganic and organic compounds were observed, including nitrate, sulfate, aliphatic acids with carbon numbers up to 18, and highly oxygenated CHO, CHON, and CHOS compounds. The latter two can be attributed to parent ions or the decomposition products of organonitrates and organosulfates/organosulfonates, respectively. Components from both primary emissions and secondary formation of UFPs were identified. Compared to the UFPs measured at forest and marine sites, those in urban Beijing contain more nitrogen-containing and sulfur-containing compounds. These observations illustrate unique features of the UFPs in the urban environment and provide insights into their origins.
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Affiliation(s)
- Xiaoxiao Li
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, 100084 Beijing, China
| | - Yuyang Li
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, 100084 Beijing, China
| | - Michael J Lawler
- Chemistry Department, University of California, Irvine, California 92697, United States
| | - Jiming Hao
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, 100084 Beijing, China
| | - James N Smith
- Chemistry Department, University of California, Irvine, California 92697, United States
| | - Jingkun Jiang
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, 100084 Beijing, China
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Abstract
Cell analysis is of great significance for the exploration of human diseases and health. However, there are not many techniques for high-throughput cell analysis in the simulated cell microenvironment. The high designability of the microfluidic chip enables multiple kinds of cells to be co-cultured on the chip, with other functions such as sample preprocessing and cell manipulation. Mass spectrometry (MS) can detect a large number of biomolecules without labelling. Therefore, the application of the microfluidic chip coupled with MS has represented a major branch of cell analysis over the past decades. Here, we concisely introduce various microfluidic devices coupled with MS used for cell analysis. The main functions of microfluidic devices are described first, followed by introductions of different interfaces with different types of MS. Then, their various applications in cell analysis are highlighted, with an emphasis on cell metabolism, drug screening, and signal transduction. Current limitations and prospective trends of microfluidics coupled with MS are discussed at the end.
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Affiliation(s)
- Wanling Zhang
- Department of Chemistry, Beijing Key Laboratory of Microanalytical Methods and Instrumentation, MOE Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology, Tsinghua University
| | - Qiang Zhang
- Department of Chemistry, Beijing Key Laboratory of Microanalytical Methods and Instrumentation, MOE Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology, Tsinghua University
| | - Jin-Ming Lin
- Department of Chemistry, Beijing Key Laboratory of Microanalytical Methods and Instrumentation, MOE Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology, Tsinghua University
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11
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Sano Y. Mass Analyzer Using an Alternating Electric Field with a Pause Period: Concept and Simulation. J Am Soc Mass Spectrom 2021; 32:404-419. [PMID: 33356227 DOI: 10.1021/jasms.0c00249] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
In this mass analyzer, pulsed ions are introduced into a separation space during a pause period of the alternating electric field. Furthermore, as defined, the measured ionic species exits from the separation space during the next pause period after receiving the action of the alternating electric field for one period. At this time, the ions of the measured ionic species are energy-focused and separated from the others by the difference in displacement caused by the electric field. In the concept section, the mass analyzer and the alternating electric field were illustrated, and the conditions that the measured ionic species should satisfy were clarified. An equation giving the displacement magnitude of the measured ionic species after one period was derived, showing that the mass separation is performed based on m/z. An equation giving the mass resolution was derived from this equation. In the simulation and discussion section, the mass separation in the alternating electric field and the energy focusing of the ions of the measured ionic species were demonstrated by numerical calculations. A scanning method that changes the period of the alternating electric field was demonstrated, showing that there is no limit to the m/z range that can be analyzed. Besides, it was demonstrated that ionic species in a required m/z range can be analyzed simultaneously with the introduction of one packet of pulsed ions. It was shown that measurement operations can be repeated with no or a little wasted time. Complementarily, the direction-focusing performance of the electric sector was examined.
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Affiliation(s)
- Yoshinori Sano
- Sano Laboratory of Reaction Chemistry, 15-4, Hinodai 1-chome, Hino-shi, Tokyo 191-0003, Japan
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12
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Bagolini A, Correale R, Picciotto A, Di Lorenzo M, Scapinello M. MEMS Membranes with Nanoscale Holes for Analytical Applications. Membranes (Basel) 2021; 11:74. [PMID: 33498406 DOI: 10.3390/membranes11020074] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/28/2020] [Revised: 01/18/2021] [Accepted: 01/19/2021] [Indexed: 11/25/2022]
Abstract
Micro-electro-mechanical membranes having nanoscale holes were developed, to be used as a nanofluidic sample inlet in novel analytical applications. Nanoscopic holes can be used as sampling points to enable a molecular flow regime, enhancing the performance and simplifying the layout of mass spectrometers and other analytical systems. To do this, the holes must be placed on membranes capable of consistently withstanding a pressure gradient of 1 bar. To achieve this goal, a membrane-in-membrane structure was adopted, where a larger and thicker membrane is microfabricated, and smaller sub-membranes are then realized in it. The nanoscopic holes are opened in the sub-membranes. Prototype devices were fabricated, having hole diameters from 300 to 600 nm, a membrane side of 80 μm, and a simulated maximum displacement of less than 150 nm under a 1 bar pressure gradient. The obtained prototypes were tested in a dedicated vacuum system, and a method to calculate the effective orifice diameter using gas flow measurements at different pressure gradients was implemented. The calculated diameters were in good agreement with the target diameter sizes. Micro-electro-mechanical technology was successfully used to develop a novel micromembrane with nanoscopic holes, and the fabricated prototypes were successfully used as a gas inlet in a vacuum system for mass spectrometry and other analytical systems.
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Devadasu E, Subramanyam R. Enhanced Lipid Production in Chlamydomonas reinhardtii Caused by Severe Iron Deficiency. Front Plant Sci 2021; 12:615577. [PMID: 33927732 PMCID: PMC8076870 DOI: 10.3389/fpls.2021.615577] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Accepted: 03/23/2021] [Indexed: 05/19/2023]
Abstract
Microalgae are used as a source of lipids for the production of biofuels. Most algae produce neutral lipids under stress conditions. Here, lipid accumulation by the unicellular alga Chlamydomonas reinhardtii was examined during cultivation under iron-limiting conditions. Severe iron stress caused the cells to accumulate a significant amount of lipid, specifically triacylglycerols (TAGs), by compromising the growth. Semi-quantitative measurements by Fourier transform infrared (FTIR) spectroscopy showed an increase in both carbohydrate and lipid content in iron-stressed C. reinhardtii cells compared to control. Analysis by flow cytometry and thin layer chromatography confirmed that severe iron deficiency-induced TAG accumulation to fourfold higher than in iron-replete control cells. This accumulation of TAGs was mostly degraded from chloroplast lipids accompanied by overexpression of diacylglycerol acyltransferase (DGAT2A) protein. Furthermore, liquid chromatography-mass spectrometry (LC-MS) analysis demonstrated significantly enhanced levels of C16:0, C18:2, and C18:3 fatty acids (FAs). These results indicate that iron stress triggers the rapid accumulation of TAGs in C. reinhardtii cells. The enhanced production of these lipids caused by the iron deficiency may contribute to the efficient production of algal biofuels if we escalate to the photobioreactor's growth conditions.
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14
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Mitema A, Feto NA, Rafudeen MS. Development and validation of TOF/Q-TOF MS/MS, HPLC method and in vitro bio-strategy for aflatoxin mitigation. Food Addit Contam Part A Chem Anal Control Expo Risk Assess 2020; 37:2149-2164. [PMID: 33151829 DOI: 10.1080/19440049.2020.1815861] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Some secondary metabolites produced by fungi are carcinogenic, hepatotoxic, and/or cause birth defects in humans and animals. We developed and optimised bio-analytical tools for detection of metabolites, aflatoxins and evaluated the effectiveness of the methods in co-infected maize tissues. Isolate KSM012 (atoxigenic) demonstrated no peaks and no blue fluorescence on HPLC and TLC plates respectively confirming non-toxicity. AFB1 and AFB2 were produced by Isolate KSM015 in addition to AFG1 and AFG2, which is an indication of possible SBG morphotype. The limits of quantification and detection ranged from 0.02 to 35.81 µg/mL and 0.01-6.8 µg/mL, respectively. The best mass spectrum with lowest noise was obtained at 100% ACN and sterile water spiked with 0.1% formic acid at a flow rate of 0.3 mL/min. The positive ion mode with electrospray ionisation application exhibited better fragmentation for mycotoxins. In total 17 metabolites were detected by targeted and formula mass. KDVI maize line exhibited high fungal colonisation in comparison to GAF4 at equal co-infection ratio 50:50. AFB1 and AFG2 were remarkably higher in GAF4 in comparison to sensitive KDV1 (p ˂ 0.05). The detection limits, linearity and sensitivity showed the method developed was suitable for the determination of mycotoxin in comparisons to the guidelines of European Commission 657/EC 2002.
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Affiliation(s)
- Alfred Mitema
- OMICS Research Group, Department of Biotechnology, Vaal University of Technology , Vanderbijlpark, South Africa.,Plant Stress Laboratory, Department of Molecular and Cell Biology, University of Cape Town , Cape Town, South Africa.,School of Biological Sciences, University of Nairobi , Nairobi, Kenya
| | - Naser Aliye Feto
- OMICS Research Group, Department of Biotechnology, Vaal University of Technology , Vanderbijlpark, South Africa
| | - Mohamed Suhail Rafudeen
- Plant Stress Laboratory, Department of Molecular and Cell Biology, University of Cape Town , Cape Town, South Africa
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15
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Chopra A, Ali SA, Bathla S, Rawat P, Vohra V, Kumar S, Mohanty AK. High-Resolution Mass Spectrometer-Based Ultra-Deep Profile of Milk Whey Proteome in Indian Zebu ( Sahiwal) Cattle. Front Nutr 2020; 7:150. [PMID: 33072792 PMCID: PMC7533583 DOI: 10.3389/fnut.2020.00150] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Accepted: 07/27/2020] [Indexed: 12/18/2022] Open
Abstract
Milk serves as a mode of protection to neonate through transferring the host defense proteins from mother to offspring. It also guards the mammary gland against various types of infections. Along with the presence of six vital proteins, bovine milk (whey) contains a massive class of minor proteins, not all of which have been comprehensively reported. In this study, we performed an LC-MS/MS-based ultra-deep identification of the milk whey proteome of Indian zebu (Sahiwal) cattle. Three independent search engines that are Comet, Tandem, and Mascot-based analysis resulted in the discovery of over 6,210 non-redundant proteins commonly identified. Genome-wise mapping revealed that chromosome 1 showed a minimum expression of 14 proteins, whereas chromosome 19 expressed 250 maximum proteins in milk whey. These results demonstrate that milk proteome in Sahiwal cattle is quite complicated, and minor milk fractions play a significant role in host defense.
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Affiliation(s)
- Alka Chopra
- Proteomics and Cell Biology Lab, Animal Biotechnology Center, National Dairy Research Institute, Karnal, India
| | - Syed Azmal Ali
- Proteomics and Cell Biology Lab, Animal Biotechnology Center, National Dairy Research Institute, Karnal, India
| | - Shveta Bathla
- Yale University School of Medicine, New Haven, CT, United States
| | - Preeti Rawat
- Proteomics and Cell Biology Lab, Animal Biotechnology Center, National Dairy Research Institute, Karnal, India
| | - Vikas Vohra
- Animal Genetics and Breeding Division, National Dairy Research Institute, Karnal, India
| | - Sudarshan Kumar
- Proteomics and Cell Biology Lab, Animal Biotechnology Center, National Dairy Research Institute, Karnal, India
| | - Ashok Kumar Mohanty
- Proteomics and Cell Biology Lab, Animal Biotechnology Center, National Dairy Research Institute, Karnal, India
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16
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Mielczarek P, Silberring J, Smoluch M. MINIATURIZATION IN MASS SPECTROMETRY. Mass Spectrom Rev 2020; 39:453-470. [PMID: 31793697 DOI: 10.1002/mas.21614] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2019] [Accepted: 11/14/2019] [Indexed: 06/10/2023]
Abstract
Expectations for continuous miniaturization in mass spectrometry are not declining for years. Portable instruments are highly welcome by the industry, science, space agencies, forensic laboratories, and many other units. All are striving for the small, cheap, and as good as possible instruments. This review describes the recent developments of miniature mass spectrometers and also provides selected applications where these devices are used. Upcoming perspectives of further development are also discussed. @ 2019 John Wiley & Sons Ltd. Mass Spec Rev.
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Affiliation(s)
- Przemyslaw Mielczarek
- Department of Biochemistry and Neurobiology, Faculty of Materials Science and Ceramics, AGH University of Science and Technology, Mickiewicza 30, 30-059, Krakow, Poland
- Laboratory of Proteomics and Mass Spectrometry, Maj Institute of Pharmacology, Polish Academy of Sciences, Smetna 12, 31-343, Krakow, Poland
| | - Jerzy Silberring
- Department of Biochemistry and Neurobiology, Faculty of Materials Science and Ceramics, AGH University of Science and Technology, Mickiewicza 30, 30-059, Krakow, Poland
- Centre of Polymer and Carbon Materials, Polish Academy of Sciences, Curie-Sklodowskiej St. 34, 41-819, Zabrze, Poland
| | - Marek Smoluch
- Department of Biochemistry and Neurobiology, Faculty of Materials Science and Ceramics, AGH University of Science and Technology, Mickiewicza 30, 30-059, Krakow, Poland
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17
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Ma C, Liu D, Li D, Zhang J, Xu XQ, Zhu H, Wan XF, Miao CH, Konkle BA, Onigman P, Xiao W, Li L. Comprehensive N- and O-glycosylation mapping of human coagulation factor V. J Thromb Haemost 2020; 18:1884-1892. [PMID: 32310329 PMCID: PMC7732234 DOI: 10.1111/jth.14861] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2020] [Revised: 04/08/2020] [Accepted: 04/10/2020] [Indexed: 12/22/2022]
Abstract
BACKGROUND/OBJECTIVE Coagulation factor V (FV), a multidomain glycoprotein, is an essential cofactor in the blood clotting cascade. FV deficiency is a rare bleeding disorder that results in poor clotting after an injury or surgery. The only treatment for the disease is infusions of fresh frozen plasma and blood platelets. Glycosylation affects the biological activity, pharmacokinetics, immunogenicity, and in vivo clearance rate of proteins in the plasma. The glycan profile of FV, as well as how it affects the activity, stability, and immunogenicity, remains unknown. METHODS In this study, we comprehensively mapped the glycosylation patterns of human plasma-derived FV by combining multienzyme digestion, hydrophilic interaction chromatography enrichment of glycopeptides, and alternated fragmentation mass spectrometry analysis. RESULTS/CONCLUSION A total of 57 unique N-glycopeptides and 51 O-glycopeptides were identified, which were categorized into 40 N-glycan and 17 O-glycan compositions. Such glycosylation details are fundamental for future functional studies and therapeutics development. In addition, the established methodology can be readily applied to analyze glycosylation patterns of proteins with more than 2000 amino acids.
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Affiliation(s)
- Cheng Ma
- Department of Chemistry, Georgia State University, Atlanta, GA, USA
| | - Ding Liu
- Department of Chemistry, Georgia State University, Atlanta, GA, USA
| | - Dong Li
- Department of Clinical Laboratory, Shanghai Tongji Hospital, Tongji University School of Medicine, Shanghai, China
| | - Junping Zhang
- Department of Microbiology and Immunology, Sol Sherry Thrombosis Research Center, Cardiovascular Research Center, Temple University, Philadelphia, PA, USA
| | - Xiao-Qian Xu
- Department of Hematology, Shanghai Jiaotong University Affiliated Shanghai General Hospital, Shanghai, China
| | - He Zhu
- Department of Chemistry, Georgia State University, Atlanta, GA, USA
| | - Xiu-Feng Wan
- Missouri University Center for Research on Influenza Systems Biology (CRISB), University of Missouri, Columbia, MO, USA
- Department of Molecular Microbiology and Immunology, School of Medicine, University of Missouri, Columbia, MO, USA
- Department of Electrical Engineering & Computer Science, College of Engineering, University of Missouri, Columbia, MO, USA
- Bond Life Sciences Center, University of Missouri, Columbia, MO, USA
- MU Informatics Institute, University of Missouri, Columbia, MO, USA
- Department of Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, MO, USA
| | - Carol H. Miao
- Center for Immunity and Immunotherapies, Seattle Children’s Research Institute, Seattle, WA, USA
- University of Washington, Seattle, WA, USA
| | - Barbara A. Konkle
- University of Washington, Seattle, WA, USA
- Bloodworks Northwest, Seattle, WA, USA
| | | | - Weidong Xiao
- Department of Microbiology and Immunology, Sol Sherry Thrombosis Research Center, Cardiovascular Research Center, Temple University, Philadelphia, PA, USA
| | - Lei Li
- Department of Chemistry, Georgia State University, Atlanta, GA, USA
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18
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Ma J, Liu M, Wang Y, Xin C, Zhang H, Chen S, Zheng X, Zhang X, Xiao F, Yang S. Quantitative proteomics analysis of young and elderly skin with DIA mass spectrometry reveals new skin aging-related proteins. Aging (Albany NY) 2020; 12:13529-13554. [PMID: 32602849 PMCID: PMC7377841 DOI: 10.18632/aging.103461] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Accepted: 05/27/2020] [Indexed: 12/16/2022]
Abstract
Skin aging is a specific manifestation of the physiological aging process that occurs in virtually all organisms. In this study, we used data independent acquisition mass spectrometry to perform a comparative analysis of protein expression in volar forearm skin samples from of 20 healthy young and elderly Chinese individuals. Our quantitative proteomic analysis identified a total of 95 differentially expressed proteins (DEPs) in aged skin compared to young skin. Enrichment analyses of these DEPs (57 upregulated and 38 downregulated proteins) based on the GO, KEGG, and KOG databases revealed functional clusters associated with immunity and inflammation, oxidative stress, biosynthesis and metabolism, proteases, cell proliferation, cell differentiation, and apoptosis. We also found that GAPDH, which was downregulated in aged skin samples, was the top hub gene in a protein-protein interaction network analysis. Some of the DEPs identified herein had been previously correlated with aging of the skin and other organs, while others may represent novel age-related entities. Our non-invasive proteomics analysis of human epidermal proteins may guide future research on skin aging to help develop treatments for age-related skin conditions and rejuvenation.
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Affiliation(s)
- Jing Ma
- Department of Dermatology of First Affiliated Hospital, and Institute of Dermatology, Anhui Medical University, Hefei, Anhui, China.,Key Laboratory of Dermatology, Anhui Medical University, Ministry of Education, Hefei, Anhui, China
| | - Mengting Liu
- Department of Dermatology of First Affiliated Hospital, and Institute of Dermatology, Anhui Medical University, Hefei, Anhui, China.,Key Laboratory of Dermatology, Anhui Medical University, Ministry of Education, Hefei, Anhui, China
| | - Yaochi Wang
- Department of Dermatology of First Affiliated Hospital, and Institute of Dermatology, Anhui Medical University, Hefei, Anhui, China.,Key Laboratory of Dermatology, Anhui Medical University, Ministry of Education, Hefei, Anhui, China
| | - Cong Xin
- Department of Dermatology of First Affiliated Hospital, and Institute of Dermatology, Anhui Medical University, Hefei, Anhui, China.,Key Laboratory of Dermatology, Anhui Medical University, Ministry of Education, Hefei, Anhui, China
| | - Hui Zhang
- Department of Dermatology of First Affiliated Hospital, and Institute of Dermatology, Anhui Medical University, Hefei, Anhui, China.,Key Laboratory of Dermatology, Anhui Medical University, Ministry of Education, Hefei, Anhui, China
| | - Shirui Chen
- Department of Dermatology of First Affiliated Hospital, and Institute of Dermatology, Anhui Medical University, Hefei, Anhui, China.,Key Laboratory of Dermatology, Anhui Medical University, Ministry of Education, Hefei, Anhui, China
| | - Xiaodong Zheng
- Department of Dermatology of First Affiliated Hospital, and Institute of Dermatology, Anhui Medical University, Hefei, Anhui, China.,Key Laboratory of Dermatology, Anhui Medical University, Ministry of Education, Hefei, Anhui, China
| | - Xuejun Zhang
- Department of Dermatology of First Affiliated Hospital, and Institute of Dermatology, Anhui Medical University, Hefei, Anhui, China.,Key Laboratory of Dermatology, Anhui Medical University, Ministry of Education, Hefei, Anhui, China
| | - Fengli Xiao
- Department of Dermatology of First Affiliated Hospital, and Institute of Dermatology, Anhui Medical University, Hefei, Anhui, China.,Key Laboratory of Dermatology, Anhui Medical University, Ministry of Education, Hefei, Anhui, China.,The Center for Scientific Research of Anhui Medical University, Hefei, Anhui, China
| | - Sen Yang
- Department of Dermatology of First Affiliated Hospital, and Institute of Dermatology, Anhui Medical University, Hefei, Anhui, China.,Key Laboratory of Dermatology, Anhui Medical University, Ministry of Education, Hefei, Anhui, China
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19
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Zhang W, Li N, Lin L, Huang Q, Uchiyama K, Lin JM. Concentrating Single Cells in Picoliter Droplets for Phospholipid Profiling on a Microfluidic System. Small 2020; 16:e1903402. [PMID: 31769602 DOI: 10.1002/smll.201903402] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2019] [Revised: 11/08/2019] [Indexed: 06/10/2023]
Abstract
Cellular membranes are composed of a variety of lipids in different amounts and proportions, and alterations of them are usually closely related to various diseases. To reveal the intercellular heterogeneity of the lipid variation, an integrated microfluidic system is designed, which consists of droplet-based inkjet printing, dielectrophoretic electrodes, and de-emulsification interface to achieve on-line single-cell encapsulation, manipulation, and mass spectrometry (MS) detection. This integrated system effectively improves the single-cell encapsulation rate, and meanwhile reduces the matrix interference and continuous oil phase interference to the MS detection. Using this system, the heterogeneities between the normal and cancer cells are compared, and the heterogeneity of the same cells before and after the drug treatment changed obviously, indicating that this system can be used as a promising tool for studying the link between the alterations of lipid homeostasis and various diseases.
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Affiliation(s)
- Weifei Zhang
- Department of Chemistry, Beijing Key Laboratory of Microanalytical Methods and Instrumentation, MOE Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology, Tsinghua University, Beijing, 100084, China
| | - Nan Li
- Department of Chemistry, Beijing Key Laboratory of Microanalytical Methods and Instrumentation, MOE Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology, Tsinghua University, Beijing, 100084, China
- CAS Key Laboratory of Standardization and Measurement for Nanotechnology, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing, 100190, China
| | - Ling Lin
- CAS Key Laboratory of Standardization and Measurement for Nanotechnology, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing, 100190, China
| | - Qiushi Huang
- Department of Chemistry, Beijing Key Laboratory of Microanalytical Methods and Instrumentation, MOE Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology, Tsinghua University, Beijing, 100084, China
| | - Katsumi Uchiyama
- Department of Applied Chemistry, Graduate School of Urban Environmental Sciences, Tokyo Metropolitan University, Minamiohsawa, Hachioji, Tokyo, 192-0397, Japan
| | - Jin-Ming Lin
- Department of Chemistry, Beijing Key Laboratory of Microanalytical Methods and Instrumentation, MOE Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology, Tsinghua University, Beijing, 100084, China
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20
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Li KW, Ganz AB, Smit AB. Proteomics of neurodegenerative diseases: analysis of human post-mortem brain. J Neurochem 2019; 151:435-445. [PMID: 30289976 PMCID: PMC6899881 DOI: 10.1111/jnc.14603] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2018] [Revised: 08/15/2018] [Accepted: 10/01/2018] [Indexed: 12/12/2022]
Abstract
Dementias are prevalent brain disorders in the aged population. Dementias pose major socio-medical burden, but currently there is no cure available. Novel proteomics approaches hold promise to identify alterations of the brain proteome that could provide clues on disease etiology, and identify candidate proteins to develop further as a biomarker. In this review, we focus on recent proteomics findings from brains affected with Alzheimer's Disease, Parkinson Disease Dementia, Frontotemporal Dementia, and Amyotrophic Lateral Sclerosis. These studies confirmed known cellular changes, and in addition identified novel proteins that may underlie distinct aspects of the diseases. This article is part of the special issue "Proteomics".
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Affiliation(s)
- K. W. Li
- Department of Molecular and Cellular NeurobiologyCenter for Neurogenomics and Cognitive ResearchAmsterdam NeuroscienceVrije UniversiteitAmsterdamThe Netherlands
| | - Andrea B. Ganz
- Department of Molecular and Cellular NeurobiologyCenter for Neurogenomics and Cognitive ResearchAmsterdam NeuroscienceVrije UniversiteitAmsterdamThe Netherlands
| | - August B. Smit
- Department of Molecular and Cellular NeurobiologyCenter for Neurogenomics and Cognitive ResearchAmsterdam NeuroscienceVrije UniversiteitAmsterdamThe Netherlands
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21
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Gassiep I, Armstrong M, Norton RE. Identification of Burkholderia pseudomallei by Use of the Vitek Mass Spectrometer. J Clin Microbiol 2019; 57:e00081-19. [PMID: 30842230 DOI: 10.1128/JCM.00081-19] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2019] [Accepted: 02/27/2019] [Indexed: 02/07/2023] Open
Abstract
Burkholderia pseudomallei is the causative agent of melioidosis. This condition most often presents as pneumonia and bacteremia, with mortality rates of 9% to 70%. Therefore, early identification of this organism may aid in directing appropriate management. This study aimed to use the Vitek matrix-assisted laser desorption ionization-time of flight mass spectrometer to create a spectrum for the rapid identification of B. pseudomallei Spectra from 85 isolate cultures were acquired using the Vitek mass spectrometer research mode. A SuperSpectrum was created using peak matching and subsequently activated for analysis of organism identification. All 85 isolates were correctly identified as B. pseudomallei A total of 899 spectra were analyzed and demonstrated a specificity of 99.8%. Eighty-one clinical isolates were used, of which 10 were neuromelioidosis, and no discernible spectrum difference was appreciated. Spectrum acquisition from a single spot was only successful in 374/899 (41%) of isolates. This increased to 100% when 3 spots of the same extract were analyzed. The Vitek mass spectrometer can be used for the rapid identification of B. pseudomallei with a high level of specificity.
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22
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Xu JY, Xu Y, Xu Z, Zhai LH, Ye Y, Zhao Y, Chu X, Tan M, Ye BC. Protein Acylation is a General Regulatory Mechanism in Biosynthetic Pathway of Acyl-CoA-Derived Natural Products. Cell Chem Biol 2018; 25:984-995.e6. [PMID: 29887264 DOI: 10.1016/j.chembiol.2018.05.005] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2017] [Revised: 03/25/2018] [Accepted: 05/01/2018] [Indexed: 11/18/2022]
Abstract
Coenzyme A (CoA) esters of short fatty acids (acyl-CoAs) function as key precursors for the biosynthesis of various natural products and the dominant donors for lysine acylation. Herein, we investigated the functional interplay between beneficial and adverse effects of acyl-CoA supplements on the production of acyl-CoA-derived natural products in microorganisms by using erythromycin-biosynthesized Saccharopolyspora erythraea as a model: accumulation of propionyl-CoA benefited erythromycin biosynthesis, but lysine propionylation inhibited the activities of important enzymes involved in biosynthetic pathways of erythromycin. The results showed that the overexpression of NAD+-dependent deacylase could circumvent the inhibitory effects of high acyl-CoA concentrations. In addition, we demonstrated the similar lysine acylation mechanism in other acyl-CoA-derived natural product biosynthesis, such as malonyl-CoA-derived alkaloid and butyryl-CoA-derived bioalcohol. These observations systematically uncovered the important role of protein acylation on interaction between the accumulation of high concentrations of acyl-CoAs and the efficiency of their use in metabolic pathways.
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Affiliation(s)
- Jun-Yu Xu
- Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals, College of Pharmaceutical Sciences, Zhejiang University of Technology, Hangzhou, Zhejiang 310014, China; State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, PR China; Lab of Biosystems and Microanalysis, State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China
| | - Ya Xu
- Lab of Biosystems and Microanalysis, State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China
| | - Zhen Xu
- Lab of Biosystems and Microanalysis, State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China
| | - Lin-Hui Zhai
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, PR China
| | - Yang Ye
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, PR China
| | - Yingming Zhao
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, PR China; Ben May Department for Cancer Research, University of Chicago, Chicago, IL 60637, USA
| | - Xiaohe Chu
- Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals, College of Pharmaceutical Sciences, Zhejiang University of Technology, Hangzhou, Zhejiang 310014, China
| | - Minjia Tan
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, PR China.
| | - Bang-Ce Ye
- Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals, College of Pharmaceutical Sciences, Zhejiang University of Technology, Hangzhou, Zhejiang 310014, China; Lab of Biosystems and Microanalysis, State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China.
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Adeola HA, Blackburn JM, Rebbeck TR, Zerbini LF. Emerging proteomics biomarkers and prostate cancer burden in Africa. Oncotarget 2017; 8:37991-8007. [PMID: 28388542 DOI: 10.18632/oncotarget.16568] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2016] [Accepted: 02/27/2017] [Indexed: 12/25/2022] Open
Abstract
Various biomarkers have emerged via high throughput omics-based approaches for use in diagnosis, treatment, and monitoring of prostate cancer. Many of these have yet to be demonstrated as having value in routine clinical practice. Moreover, there is a dearth of information on validation of these emerging prostate biomarkers within African cohorts, despite the huge burden and aggressiveness of prostate cancer in men of African descent. This review focusses of the global landmark achievements in prostate cancer proteomics biomarker discovery and the potential for clinical implementation of these biomarkers in Africa. Biomarker validation processes at the preclinical, translational and clinical research level are discussed here, as are the challenges and prospects for the evaluation and use of novel proteomic prostate cancer biomarkers.
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Praca ELL, Tiller CJ, Kisling JA, Tepper RS. An alternative method to measure the diffusing capacity of the lung for carbon monoxide in infants. Pediatr Pulmonol 2018; 53:332-336. [PMID: 29265767 DOI: 10.1002/ppul.23926] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/03/2017] [Accepted: 11/16/2017] [Indexed: 11/09/2022]
Abstract
BACKGROUND Lung diffusion assessed by the uptake of carbon monoxide (DLCO ) and alveolar volume (VA ) by inert gas dilution are readily assessed in cooperative older subjects; however, obtaining these measurements in infants has been much more difficult. Our laboratory has measured DLCO and VA in sleeping infants using a mass spectrometer, which continuously measures gas concentrations, and demonstrated that infants with bronchopulmonary dysplasia (BPD) have lower DLCO , but no difference in VA compared to full-term controls. The mass spectrometer is expensive and lacks portability; therefore, we evaluated whether measurement of end-expiratory alveolar gas concentrations using a gas chromatograph would provide an alternative approach. METHODS (1) Using our previously digitized data for infants with BPD and full-term controls, DLCO and VA were calculated at end-expiration rather than between 60 and 80% of expired volume, as previously reported. (2) In a new group of infants, DLCO and VA were measured using gas concentrations obtained at end-expiration with a mass spectrometer and a gas chromatograph. RESULTS (1) Using end-expiratory concentrations, infants with BPD (n = 49) had significantly lower DLCO , but similar VA compared to healthy controls (n = 34) (DLCO : 4.2 vs 4.6 mL/min/mmHg, P = 0.047; VA : 614 vs 608 mL, P = 0.772). (2) Among newly evaluated infants (n = 28), DLCO and VA obtained with a mass spectrometer and a gas chromatograph were highly correlated (R2 = 0.94 and 0.99, respectively), and were not significantly different for the two analyzers. CONCLUSION Measuring DLCO and VA at end-expiration using a gas chromatograph can provide an effective assessment of gas exchange in sleeping infants.
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Affiliation(s)
- Eduardo L L Praca
- Department of Pediatric Pulmonology and Respiratory Care, James Whitcomb Riley Hospital for Children, Indiana University School of Medicine, Indianapolis, Indiana
| | - Christina J Tiller
- Department of Pediatric Pulmonology and Respiratory Care, James Whitcomb Riley Hospital for Children, Indiana University School of Medicine, Indianapolis, Indiana
| | - Jeffrey A Kisling
- Department of Pediatric Pulmonology and Respiratory Care, James Whitcomb Riley Hospital for Children, Indiana University School of Medicine, Indianapolis, Indiana
| | - Robert S Tepper
- Department of Pediatric Pulmonology and Respiratory Care, James Whitcomb Riley Hospital for Children, Indiana University School of Medicine, Indianapolis, Indiana
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Chao CC, Ingram BO, Lurchachaiwong W, Ching WM. Metabolic characterization of serum from mice challenged with Orientia tsutsugamushi-infected mites. New Microbes New Infect 2018; 23:70-6. [PMID: 29692908 DOI: 10.1016/j.nmni.2018.01.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2018] [Revised: 01/18/2018] [Accepted: 01/18/2018] [Indexed: 01/31/2023] Open
Abstract
Scrub typhus is an acute zoonosis caused by the obligate intracellular Gram-negative bacterium Orientia tsutsugamushi. To better understand the host response elicited by natural infection by chigger feeding, ICR mice were infected by Leptotrombidium chiangraiensis (Lc1) chiggers, and the metabolic profiles of their serum were examined over several time points after initiation of feeding. ICR mice were infected by either naive Lc1 chiggers (i.e. not infected by O. tsutsugamushi, NLc1) or O. tsutsugamushi–infected Lc1 chiggers (OLc1). Serum was collected from both groups of mice at 6 hours and 10 days after initiation of feeding. Metabolites were extracted from the serum and analysed by ultra performance liquid chromatography–tandem mass spectrometry. The resulting ion/chromatographic features were matched to a library of chemical standards for identification and quantification. Biochemicals that differed significantly between the experimental groups were identified using Welch's two-sample t tests; p ≤ 0.05 was considered statistically significant. A number of biochemicals linked to immune function were found to be significantly altered between mice infected by the NLc1 and OLc1 chiggers, including itaconate, kynurenine and histamine. Several metabolites linked to energy production were also found to be altered in the animals. In addition lipid and carbohydrate metabolism, bile acid and phospholipid homeostasis, and nucleotide metabolism were also found to be different in these two groups of mice. Markers of stress and food intake were also significantly altered. Global untargeted metabolomic characterization revealed significant differences in the biochemical profiles of mice infected by the NLc1 versus OLc1 chiggers. These findings provide an important platform for further investigation of the host responses associated with chigger-borne O. tsutsugamushi infections.
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Liu J, Song J, Huang K, Michel D, Fang J. HPLC-MS/MS analysis of anthocyanins in human plasma and urine using protein precipitation and dilute-and-shoot sample preparation methods, respectively. Biomed Chromatogr 2018; 32:e4177. [PMID: 29251356 DOI: 10.1002/bmc.4177] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2017] [Revised: 12/04/2017] [Accepted: 12/07/2017] [Indexed: 11/11/2022]
Abstract
A high-performance liquid chromatography tandem-mass spectrometry (HPLC-MS/MS) method has been developed to analyze anthocyanins in urine and plasma to further understand their absorption, distribution, metabolism and excretion. The method employed a Synergi RP-Max column (250 × 4.6 mm, 4 μm) and an API 4000 mass spectrometer. A gradient elution system consisted of mobile phase A (water-1% formic acid) and mobile phase B (acetonitrile) with a flow rate of 0.60 mL/min. The gradient was initiated at 5% B, increased to 21% B at 20 min, and then increased to 40% B at 35 min. The analysis of anthocyanins presents a challenge because of the poor stability of anthocyanins during sample preparation, especially during solvent evaporation. In this method, the degradation of anthocyanins was minimized using protein precipitation and dilute-and-shoot and sample preparation methods for plasma and urine, respectively. No interferences were observed from endogenous compounds. The method has been used to analyze anthocyanin concentrations in urine and plasma samples from volunteers administered saskatoon berries. Cyanidin-3-galactoside, cyanidin-3-glucoside, cyanidin-3-arabinoside, cyanidin-3-xyloside and quercetin-3-galactoside, the five major flavonoid components in saskatoon berries, were identified in plasma and urine samples.
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Affiliation(s)
- Junguo Liu
- College of Bioscience and Bioengineering, Hebei University of Science and Technology, Shijiazhuang, Hebei Province, People's Republic of China
| | - Jiuxue Song
- College of Pharmacy and Nutrition, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Karen Huang
- College of Pharmacy and Nutrition, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Deborah Michel
- College of Pharmacy and Nutrition, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Jim Fang
- College of Pharmacy and Nutrition, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
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Muneer S, Wei H, Park YG, Jeong HK, Jeong BR. Proteomic Analysis Reveals the Dynamic Role of Silicon in Alleviation of Hyperhydricity in Carnation Grown In Vitro. Int J Mol Sci 2017; 19:E50. [PMID: 29295554 PMCID: PMC5796000 DOI: 10.3390/ijms19010050] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2017] [Revised: 12/12/2017] [Accepted: 12/22/2017] [Indexed: 11/21/2022] Open
Abstract
The present study depicted the role of silicon in limiting the hyperhydricity in shoot cultures of carnation through proteomic analysis. Four-week-old healthy shoot cultures of carnation "Purple Beauty" were sub-cultured on Murashige and Skoog medium followed with four treatments, viz. control (-Si/-Hyperhydricity), hyperhydric with no silicon treatment (-Si/+Hyperhydricity), hyperhydric with silicon treatment (+Si/+Hyperhydricity), and only silicon treated with no hyperhydricity (+Si/-Hyperhydricity). Comparing to control morphological features of hyperhydric carnations showed significantly fragile, bushy and lustrous leaf nature, while Si supply restored these effects. Proteomic investigation revealed that approximately seventy protein spots were differentially expressed under Si and/or hyperhydric treatments and were either up- or downregulated in abundance depending on their functions. Most of the identified protein spots were related to stress responses, photosynthesis, and signal transduction. Proteomic results were further confirmed through immunoblots by selecting specific proteins such as superoxide dismutase (SOD), ascorbate peroxidase (APX), catalase (CAT), PsaA, and PsbA. Moreover, protein-protein interaction was also performed on differentially expressed protein spots using specific bioinformatic tools. In addition, stress markers were analyzed by histochemical localization of hydrogen peroxide (H₂O₂) and singlet oxygen (O₂1-). In addition, the ultrastructure of chloroplasts in hyperhydric leaves significantly resulted in inefficiency of thylakoid lamella with the loss of grana but were recovered in silicon supplemented leaves. The proteomic study together with physiological analysis indicated that Si has a substantial role in upholding the hyperhydricity in in vitro grown carnation shoot cultures.
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Affiliation(s)
- Sowbiya Muneer
- Division of Applied Life Science (BK21 Plus program), Gyeongsang National University, Jinju 52828, Korea.
| | - Hao Wei
- Division of Applied Life Science (BK21 Plus program), Gyeongsang National University, Jinju 52828, Korea.
| | - Yoo Gyeong Park
- Institute of Agriculture and Life Science, Gyeongsang National University, Jinju 52828, Korea.
| | - Hai Kyoung Jeong
- Division of Applied Life Science (BK21 Plus program), Gyeongsang National University, Jinju 52828, Korea.
| | - Byoung Ryong Jeong
- Division of Applied Life Science (BK21 Plus program), Gyeongsang National University, Jinju 52828, Korea.
- Institute of Agriculture and Life Science, Gyeongsang National University, Jinju 52828, Korea.
- Research Institute of Life Science, Gyeongsang National University, Jinju 52828, Korea.
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28
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Akmalov AE, Chistyakov AA, Kotkovskii GE. Laser-stimulated desorption of organic molecules from surfaces, as a method of increasing the efficiency of ion mobility spectrometry analysis. Eur J Mass Spectrom (Chichester) 2017; 23:174-180. [PMID: 29028396 DOI: 10.1177/1469066717714417] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Application of laser-induced desorption was investigated as a method of increasing the efficiency of gas phase analyzers on principles of field asymmetric ion mobility spectrometry. Mass spectrometric data of investigations of laser desorption of pentaerythritoltetranitrate molecules and cyclotetramethylenetetranitramine molecules from quartz substrate under vacuum were obtained. Laser sources a Nd3+:YAG with nanosecond pulse duration (λ = 532 nm) and a continuous wave diode laser (λ = 440 nm) were used. It was shown that both laser sources have different desorption abilities. This is expressed in various time of appearance of desorbed products that is caused by different heating mechanisms of surface layer. The desorbed quantity under action of both laser sources exceeds the detection threshold for all modern gas phase analyzers. It should be noted that despite the presence of surface dissociation of explosives under laser radiation, the quantity of nondissociated molecules is large enough for detection by ion mobility and field asymmetric ion mobility spectrometers. The optimal parameters of laser radiation for effective removal (evaporation) molecules of low-volatile compounds from surfaces are defined. The conclusion about preferable use of a Nd3+:YAG laser for increasing the detection ability of detectors based on ion mobility spectrometry was made.
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Affiliation(s)
- Artem E Akmalov
- National Research Nuclear University, Moscow Engineering Physics Institute, Moscow, Russian Federation
| | - Alexander A Chistyakov
- National Research Nuclear University, Moscow Engineering Physics Institute, Moscow, Russian Federation
| | - Gennadii E Kotkovskii
- National Research Nuclear University, Moscow Engineering Physics Institute, Moscow, Russian Federation
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Anand S, Young S, Esplin MS, Peaden B, Tolley HD, Porter TF, Varner MW, D'Alton ME, Jackson BJ, Graves SW. Detection and confirmation of serum lipid biomarkers for preeclampsia using direct infusion mass spectrometry. J Lipid Res 2016; 57:687-96. [PMID: 26891737 DOI: 10.1194/jlr.p064451] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2015] [Indexed: 02/02/2023] Open
Abstract
Despite substantial research, the early diagnosis of preeclampsia remains elusive. Lipids are now recognized to be involved in regulation and pathophysiology of some disease. Shotgun lipidomic studies were undertaken to determine whether serum lipid biomarkers exist that predict preeclampsia later in the same in pregnancy. A discovery study was performed using sera collected at 12-14 weeks pregnancy from 27 controls with uncomplicated pregnancies and 29 cases that later developed preeclampsia. Lipids were extracted and analyzed by direct infusion into a TOF mass spectrometer. MS signals, demonstrating apparent differences were selected, their abundances determined, and statistical differences tested. Statistically significant lipid markers were reevaluated in a second confirmatory study having 43 controls and 37 preeclampsia cases. Multi-marker combinations were developed using those lipid biomarkers confirmed in the second study. The initial study detected 45 potential preeclampsia markers. Of these, 23 markers continued to be statistically significant in the second confirmatory set. Most of these markers, representing several lipid classes, were chemically characterized, typically providing lipid class and potential molecular components using MS(2) Several multi-marker panels with areas under the curve >0.85 and high predictive values were developed. Developed panels of serum lipidomic biomarkers appear to be able to identify most women at risk for preeclampsia in a given pregnancy at 12-14 weeks gestation.
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Affiliation(s)
- Swati Anand
- Departments of Chemistry and Biochemistry, Brigham Young University, Provo, UT
| | - SydneyA Young
- Departments of Chemistry and Biochemistry, Brigham Young University, Provo, UT
| | - M Sean Esplin
- Maternal Fetal Medicine, Intermountain Healthcare, Salt Lake City, UT Department of Obstetrics and Gynecology, University of Utah Health Sciences Center, Salt Lake City, UT
| | | | | | - T Flint Porter
- Maternal Fetal Medicine, Intermountain Healthcare, Salt Lake City, UT Department of Obstetrics and Gynecology, University of Utah Health Sciences Center, Salt Lake City, UT
| | - Michael W Varner
- Department of Obstetrics and Gynecology, University of Utah Health Sciences Center, Salt Lake City, UT Maternal Fetal Medicine, Intermountain Healthcare, Salt Lake City, UT
| | - Mary E D'Alton
- Department of Obstetrics and Gynecology, Columbia University School of Medicine, New York, NY
| | - Bruce J Jackson
- Departments of Chemistry and Biochemistry, Brigham Young University, Provo, UT
| | - Steven W Graves
- Departments of Chemistry and Biochemistry, Brigham Young University, Provo, UT
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30
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Hou X, Du Q, Li R, Zhou M, Wang H, Wang L, Guo C, Chen T, Shaw C. Feleucin-BO1: a novel antimicrobial non-apeptide amide from the skin secretion of the toad, Bombina orientalis, and design of a potent broad-spectrum synthetic analogue, feleucin-K3. Chem Biol Drug Des 2014; 85:259-67. [PMID: 25056849 DOI: 10.1111/cbdd.12396] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2014] [Revised: 06/26/2014] [Accepted: 07/03/2014] [Indexed: 11/28/2022]
Abstract
Feleucins-BV1 and -BV2 are recently described prototypes of a novel antimicrobial non-apeptide (AMP) family identified in the skin secretion of the bombinid toad, Bombina variegata. They are encoded on different precursors that also encode a novel bombinin. Here we describe the identification of feleucin-BO1 (FLGLLGSLLamide) which is co-encoded with a different novel bombinin, named feleucin precursor-associated bombinin (FPA-bombinin-BO), from the skin secretion of Bombina orientalis. Synthetic feleucin-BO1 displayed activity against a reference Gram-positive bacterium. Staphylococcus aureus (MIC 34 μm) but was inactive (> 250 μm) against the Gram-negative bacterium, Escherichia coli, and the yeast, Candida albicans. This pattern of activity was similar to that of the prototypes. Design and synthesis of a cationicity-enhanced analogue, feleucin-K3 (F-K3), in which the amino acid residues at positions 3 (G), 6 (G) and 7 (S) of feleucin-BO1 were substituted with Lys (K) residues, resulted in a peptide with significantly enhanced potency and spectrum of activity. The MICs of F-K3 against the reference micro-organisms were 7 μm (S. aureus), 14 μm (E. coli) and 7 μm (C. albicans). These data indicate that the skin secretions of amphibians can continue to provide novel peptide templates for the rational design of analogues with possible therapeutic utility.
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Affiliation(s)
- Xiaojuan Hou
- School of Pharmaceutical Sciences, China Medical University, Shenyang, Liaoning, 110001, China; Natural Drug Discovery Group, School of Pharmacy, Queen's University, Belfast, BT9 7BL, UK
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31
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Nuño M, Ball RJ, Bowen CR. Study of solid/gas phase photocatalytic reactions by electron ionization mass spectrometry. J Mass Spectrom 2014; 49:716-726. [PMID: 25044899 DOI: 10.1002/jms.3396] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2014] [Revised: 05/07/2014] [Accepted: 05/12/2014] [Indexed: 06/03/2023]
Abstract
This paper describes a novel methodology for the real-time study of solid-gas phase photocatalytic reactions in situ. A novel reaction chamber has been designed and developed to facilitate the investigation of photoactive materials under different gas compositions. UV irradiation in the wavelength of ranges 376-387 and 381-392 nm was provided using specially designed high efficiency light emitting diode arrays. The experiments used air containing 190 ppm NO2 in a moist environment with a relative humidity of 0.1%. Photocatalytic samples consisting of pressed pellets of rutile and anatase crystalline forms of TiO2 were monitored over a period of 150 min. An ultra-high vacuum right angled bleed valve allowed a controlled flow of gas from the main reaction chamber at atmospheric pressure to a residual gas analyser operating at a vacuum of 10(-5) mbar. The apparatus and methodology have been demonstrated to provide high sensitivity (ppb). The rate of degradation of NO2 attributed to reaction at the TiO2 surface was sensitive to both crystal structures (anatase or rutile) and wavelength of irradiation.
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Affiliation(s)
- Manuel Nuño
- BRE Centre for Innovative Construction Materials, Department of Architecture and Civil Engineering, University of Bath, Bath BA2 7AY, UK
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Chen P, Sun J, Ford P. Differentiation of the four major species of cinnamons (C. burmannii, C. verum, C. cassia, and C. loureiroi) using a flow injection mass spectrometric (FIMS) fingerprinting method. J Agric Food Chem 2014; 62:2516-2521. [PMID: 24628250 PMCID: PMC3983393 DOI: 10.1021/jf405580c] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2013] [Revised: 02/25/2014] [Accepted: 03/07/2014] [Indexed: 06/01/2023]
Abstract
A simple and efficient flow injection mass spectrometric (FIMS) method was developed to differentiate cinnamon (Cinnamomum) bark (CB) samples of the four major species (C. burmannii, C. verum, C. aromaticum, and C. loureiroi) of cinnamon. Fifty cinnamon samples collected from China, Vietnam, Indonesia, and Sri Lanka were studied using the developed FIMS fingerprinting method. The FIMS fingerprints of the cinnamon samples were analyzed using principal component analysis (PCA). The FIMS technique required only 1 min of analysis time per sample. The representative samples from each of the four major species of cinnamon were further examined using an ultrahigh-performance liquid chromatography-high-resolution mass spectrometry system, and the chemical differences between the four species were profiled. The results showed that the 1 min FIMS fingerprinting method successfully differentiated the four cinnamon species studied.
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Affiliation(s)
- Pei Chen
- Food
Composition and Methods Development Laboratory, Beltsville Human Nutrition
Research Center, Agricultural Research Service, U.S. Department of Agriculture, Beltsville, Maryland 20705, United States
| | - Jianghao Sun
- Food
Composition and Methods Development Laboratory, Beltsville Human Nutrition
Research Center, Agricultural Research Service, U.S. Department of Agriculture, Beltsville, Maryland 20705, United States
| | - Paul Ford
- McCormick
Applied Research, Technical Innovation Center, McCormick and Company, Inc., 204 Wight Avenue, Hunt Valley, Maryland 21031, United
States
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Jiang Y, Laverty KS, Brown J, Nunez M, Brown L, Chagoya J, Burow M, Quigg A. Effects of fluctuating temperature and silicate supply on the growth, biochemical composition and lipid accumulation of Nitzschia sp. Bioresour Technol 2014; 154:336-344. [PMID: 24413451 DOI: 10.1016/j.biortech.2013.12.068] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2013] [Revised: 12/11/2013] [Accepted: 12/14/2013] [Indexed: 06/03/2023]
Abstract
Nitzschia sp. (Bacillariophyceae) was grown under temperature and photoperiods mimicking those, typical during summer, spring/fall and winter conditions in the southern United States, and using five silicate (Si) concentrations. In general, higher Si concentrations resulted in higher growth rates in summer and spring/fall conditions and lower organic content. Si-deficient Nitzschia sp. had higher levels of neutral lipid compared to those growing in Si replete media. Under summer conditions, the proportion of saturated fatty acids (SFA) and monounsaturated fatty acids (MUFA) was relatively stable compared with spring/fall and winter conditions, and the proportion of polyunsaturated fatty acids (PUFA) was low. In the winter condition, SFA and MUFA showed a gradient of decreasing abundance while PUFA gradients increased with increasing Si concentrations in the medium. Cumulative productivity (optimization of growth and lipid content) would be best in the spring/fall but less so in the other conditions for this strain of Nitzschia sp.
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Affiliation(s)
- Yuelu Jiang
- Department of Marine Biology, Texas A&M University at Galveston, Galveston, 77553 TX, USA.
| | | | - Jola Brown
- Texas Agrilife Research, Texas A&M University, Pecos, 79772 TX, USA
| | - Marcella Nunez
- Department of Marine Biology, Texas A&M University at Galveston, Galveston, 77553 TX, USA
| | - Lou Brown
- Texas Agrilife Research, Texas A&M University, Pecos, 79772 TX, USA
| | - Jennifer Chagoya
- Texas AgriLife Research, Texas A&M System, Lubbock, 79403 TX, USA
| | - Mark Burow
- Texas AgriLife Research, Texas A&M System, Lubbock, 79403 TX, USA
| | - Antonietta Quigg
- Department of Marine Biology, Texas A&M University at Galveston, Galveston, 77553 TX, USA; Department of Oceanography, Texas A&M University, College Station, 77843 TX, USA
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Jörundsdóttir H, Löfstrand K, Svavarsson J, Bignert A, Bergman Å. Polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecane (HBCD) in seven different marine bird species from Iceland. Chemosphere 2013; 93:1526-1532. [PMID: 23987577 DOI: 10.1016/j.chemosphere.2013.07.061] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2013] [Revised: 06/06/2013] [Accepted: 07/21/2013] [Indexed: 06/02/2023]
Abstract
Data on distribution, concentration and trends of polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecanes (HBCDs) is scarce in biota from the sub-Arctic region of the Atlantic. The present study is an investigation on PBDE and HBCD concentrations in eggs from seven marine bird species from Iceland, i.e. common eider (Somateria mollissima), arctic tern (Sterna paradisaea), guillemot (Uria aalge), fulmar (Fulmarus glacialis), lesser black-backed gull (Larus fuscus), great black-backed gull (Larus marinus) and great skua (Stercorarius skua). Concentrations of sum PBDEs ranged from 44 ng g(-1)fat in eider eggs to 2400 ng g(-1)fat in great skua eggs. The contribution of different PBDE congeners to the sum concentration differed between species. Concentration of HBCDs (sum of α-,β(-) and γ-HBCD) ranged from 1.3 ng g(-1)fat in arctic tern eggs to 41 ng g(-1)fat in great black-backed gull. PCA on PBDE and HBCD shows different trends between the two BFR groups, further indicating different sources/usage. Investigations on any potential health or population effects of environmental pollutants on the great skua are advised since both the PBDE and HBCD concentrations are high.
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Affiliation(s)
- Hrönn Jörundsdóttir
- Environmental Chemistry Unit, Department of Materials and Environmental Chemistry, Stockholm University, SE-106 91 Stockholm, Sweden; Matis Ltd., Icelandic Food and Biotech R&D, Vínlandsleið 12, 113 Reykjavík, Iceland.
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Du C, Ramaley C, McLean H, Leonard SC, Miller J. High-performance liquid chromatography coupled with tandem mass spectrometry for the detection of amyloid Beta peptide related with Alzheimer's disease. J Biomol Tech 2005; 16:356-63. [PMID: 16522857 PMCID: PMC2291744] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
Recent studies show that quantitative and qualitative differences in amyloid beta (Abeta ) peptides may be implicated in the development of Alzheimer's disease. New evidence seems to support the existence of a dynamic equilibrium between Abeta peptide in the brain and peripheral blood circulation. The quantitation of Abeta in the blood may allow the development of the potential value of Abeta peptides as a biomarker in the development of Alzheimer's disease. In this communication, quantitation of Abeta peptides using high-performance liquid chromatography coupled with tandem mass spectrometry in a linear ion trap mode is presented. RP-HPLC was performed using a Waters Xterra MS C8 column (3.0 mm x 150 mm). Abeta(1-40) peptide was eluted using a gradient elution program. Eluate from the RP-HPLC column was split to both the UV detector and electrospray ionization MS source. The product ion scan was performed in a linear ion trap mode utilizing the transition of a multiply charged molecular ion of Abeta(1-40) to a singly charged product ion. The detection limit of 31.25 ng in column load using a 3.0-mm-diameter conventional C8 column was achieved. The Abeta(1-40) standard calibration curves show excellent linearity from 34 ng to 2500 ng Abeta(1-40) of column sample load. The product ion scan enhances sensitivity 10 times compared with the best previously achieved by a single-quadrupole instrument in the selective ion monitoring mode. Moreover, the product ion scan of Abeta(1-40) provides superior selectivity and specificity, which is very important in the quantitation of Abeta(1-40) in a complex biological matrix.
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Affiliation(s)
- Chengan Du
- School of Pharmacy, Hampton University, VA 23668, USA.
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36
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Abstract
Trends in mass analyzer development are reviewed here with an emphasis on tandem mass spectrometers. The move toward "hybridization" of conventional mass analyzers to allow additional instrument functionality in tandem mass spectrometry is discussed.
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Affiliation(s)
- James W Hager
- MDS SCIEX, 71 Four Valley Drive, Concord, Ontario L4K 4V8, Canada.
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37
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Ku H, Schaefer F, Valkiers S, De Bièvre P. A Three-Ratio Scheme for the Measurement of Isotopic Ratios of Silicon. J Res Natl Inst Stand Technol 1993; 98:225-229. [PMID: 28053469 PMCID: PMC4909180 DOI: 10.6028/jres.098.017] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Accepted: 12/24/1992] [Indexed: 06/06/2023]
Abstract
This paper proposes a scheme of measurement sequences that has been used for the redetermination of the molar mass (atomic weight) of silicon at the Central Bureau for Nuclear Measurements (now Institute for Reference Materials and Measurements). This scheme avoids correlations among the measured ratios caused by normalizing all ion current measurements to that of the largest ion current. It also provides additional information for checking on the consistency of these ratios within a cycle of scans. Measurements of isotope abundance ratios of silicon are used as an illustration.
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Affiliation(s)
- Harry Ku
- National Institute of Standards and Technology, Gaithersburg, MD 20899-0001
| | - Frank Schaefer
- Institute for Reference Materials and Measurements, Commission of the European Communities, JRC, B-2440 Geel, Belgium
| | - Staf Valkiers
- Institute for Reference Materials and Measurements, Commission of the European Communities, JRC, B-2440 Geel, Belgium
| | - Paul De Bièvre
- Institute for Reference Materials and Measurements, Commission of the European Communities, JRC, B-2440 Geel, Belgium
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Dibeler VH, Walker JA, Liston SK. Mass Spectrometric Study of Photoionization. VII. Nitrogen Dioxide and Nitrous Oxide. J Res Natl Bur Stand A Phys Chem 1967; 71A:371-378. [PMID: 31824061 PMCID: PMC6624716 DOI: 10.6028/jres.071a.042] [Citation(s) in RCA: 66] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
Photoionization efficiency curves are obtained for the molecule and fragment ions of NO2 and N2O from ionization threshold to 600 Å. Features of the molecule ion curves are ascribed to autoionization and the Rydberg levels are correlated with reported spectroscopic observations. The minimum onset of ionization for NO2 occurs at 1272 Å (9.75 eV). The threshold value of 12.34 eV for the NO+ fragment results in D(NO-O) of 3.09 eV in good agreement with that calculated from thermochemical heats of formation. The 0+ ion is apparently formed with 0.1 eV excess energy. The minimum threshold energy for the N2O+ ion is 962 Å (12.89 eV). TheN 2 + fragment ion curve has a threshold at 17.29 eV corresponding to the thermochemical bond energy, D(N2 - 0)= 1.67 eV. However a lower-energy threshold at 15.57 eV is ascribed to ionization of molecular nitrogen from an unknown source. There is no evidence for an ion-pair process. The ground state transition for NO+ is forbidden by spin conservation rules. The observed threshold is 0.8 eV in excess of the calculated value and suggests a vibrationally excited state of the ion. The N+ ion is also formed with excess energy.
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Affiliation(s)
- Vernon H Dibeler
- Institute for Basic Standards, National Bureau of Standards, Washington, D.C. 20234
| | - James A Walker
- Institute for Basic Standards, National Bureau of Standards, Washington, D.C. 20234
| | - Susan K Liston
- Institute for Basic Standards, National Bureau of Standards, Washington, D.C. 20234
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39
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Abstract
Photoionization efficiency curves are obtained for the molecule and fragment ions of H2O and NH3 in the wavelength region extending from onset of ionization to 600 Å. Threshold values of 12.593 eV and 10.162 eV are observed for the H2O+ andNH 3 + ions, respectively. Vibrationally excited states of the molecule ions and autoionization of Rydberg levels are observed. A determination of the bond angle of the H2O+ ion from the Franck-Condon factors of the bending overtones results in a value of 112 degrees. Threshold values of the fragment ions permit calculations of heats of formation of the OH+ andNH 2 + ions and result in the ionization energies,I ( OH ) = 12.94 eV and I ( NH 2 ) = 11.22 eV . .
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Affiliation(s)
- Vernon H Dibeler
- Institute for Basic Standards, National Bureau of Standards, Washington, D.C. 20234
| | - James A Walker
- Institute for Basic Standards, National Bureau of Standards, Washington, D.C. 20234
| | - Henry M Rosenstock
- Institute for Basic Standards, National Bureau of Standards, Washington, D.C. 20234
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