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1.
Yakugaku Zasshi ; 140(10): 1251-1258, 2020.
Artigo em Japonês | MEDLINE | ID: mdl-32999204

RESUMO

Natural materials such as crude drugs and foods are mixtures composed of various metabolites. Metabolic profiling is often used to identify possible correlations between a compound's metabolic profile and pharmacologic activity. Direct-injection electron ionization-mass spectrometry (DI-EI-MS) is a novel metabolomics method useful for characterizing biological materials. This review demonstrates the establishment of a DI-EI-MS method for metabolic profiling using several closely related lichen species: Cladonia krempelhuberi, C. gracilis, C. pseudogymnopoda, and C. ramulosa. The qualitative DI-EI-MS method was used to profile major and/or minor constituents in extracts of lichen samples. Each lichen sample could be distinguished by altering the DI-EI-MS electron energy and examining the resulting data using one-way analysis of variance. We also attempted to predict pharmacologic activity using DI-EI-MS metabolomics. Blueberry leaf extracts inhibited the proliferation of adult T-cell leukemia (ATL) cells. Blueberry leaf extracts could be distinguished by principal component analysis based on the absolute intensity of characteristic fragment ions. Twenty cultivars were categorized into four species, and the most appropriate discriminative marker m/z value for identifying each cultivar was selected statistically. Components extracted based on DI-EI-MS analyses could be used to construct a model to predict ATL cell bioactivity. These data suggest that the novel DI-EI-MS metabolomics method is suitable for identifying species of natural materials and predicting their pharmacologic activity. This approach could enhance public health by facilitating evaluations of pharmacologic activity and functionality, leading to the elimination of counterfeit products.


Assuntos
Produtos Biológicos/metabolismo , Produtos Biológicos/farmacologia , Mirtilos Azuis (Planta)/química , Mirtilos Azuis (Planta)/metabolismo , Líquens/metabolismo , Metabolômica , Extratos Vegetais/farmacologia , Proliferação de Células/efeitos dos fármacos , Previsões , Humanos , Leucemia-Linfoma de Células T do Adulto/patologia , Espectrometria de Massas/métodos , Metabolômica/métodos , Extratos Vegetais/isolamento & purificação
2.
Nat Commun ; 11(1): 5047, 2020 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-33028810

RESUMO

COVID-19, caused by SARS-CoV-2, lacks effective therapeutics. Additionally, no antiviral drugs or vaccines were developed against the closely related coronavirus, SARS-CoV-1 or MERS-CoV, despite previous zoonotic outbreaks. To identify starting points for such therapeutics, we performed a large-scale screen of electrophile and non-covalent fragments through a combined mass spectrometry and X-ray approach against the SARS-CoV-2 main protease, one of two cysteine viral proteases essential for viral replication. Our crystallographic screen identified 71 hits that span the entire active site, as well as 3 hits at the dimer interface. These structures reveal routes to rapidly develop more potent inhibitors through merging of covalent and non-covalent fragment hits; one series of low-reactivity, tractable covalent fragments were progressed to discover improved binders. These combined hits offer unprecedented structural and reactivity information for on-going structure-based drug design against SARS-CoV-2 main protease.


Assuntos
Betacoronavirus/química , Cisteína Endopeptidases/química , Fragmentos de Peptídeos/química , Proteínas não Estruturais Virais/química , Betacoronavirus/enzimologia , Sítios de Ligação , Domínio Catalítico , Cristalografia por Raios X , Cisteína Endopeptidases/metabolismo , Desenho de Fármacos , Espectrometria de Massas , Modelos Moleculares , Fragmentos de Peptídeos/metabolismo , Conformação Proteica , Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/metabolismo , Eletricidade Estática , Proteínas não Estruturais Virais/metabolismo
3.
J Am Soc Mass Spectrom ; 31(10): 2013-2024, 2020 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-32880453

RESUMO

As corona virus disease 2019 (COVID-19) is a rapidly growing public health crisis across the world, our knowledge of meaningful diagnostic tests and treatment for severe acute respiratory syndrome coronavirus 2 (SARS-COV-2) is still evolving. This novel coronavirus disease COVID-19 can be diagnosed using RT-PCR, but inadequate access to reagents, equipment, and a nonspecific target has slowed disease detection and management. Precision medicine, individualized patient care, requires suitable diagnostics approaches to tackle the challenging aspects of viral outbreaks where many tests are needed in a rapid and deployable approach. Mass spectrometry (MS)-based technologies such as proteomics, glycomics, lipidomics, and metabolomics have been applied in disease outbreaks for identification of infectious disease agents such as virus and bacteria and the molecular phenomena associated with pathogenesis. Matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF/MS) is widely used in clinical diagnostics in the United States and Europe for bacterial pathogen identification. Paper spray ionization mass spectrometry (PSI-MS), a rapid ambient MS technique, has recently open a new opportunity for future clinical investigation to diagnose pathogens. Ultra-high-pressure liquid chromatography coupled high-resolution mass spectrometry (UHPLC-HRMS)-based metabolomics and lipidomics have been employed in large-scale biomedical research to discriminate infectious pathogens and uncover biomarkers associated with pathogenesis. PCR-MS has emerged as a new technology with the capability to directly identify known pathogens from the clinical specimens and the potential to identify genetic evidence of undiscovered pathogens. Moreover, miniaturized MS offers possible applications with relatively fast, highly sensitive, and potentially portable ways to analyze for viral compounds. However, beneficial aspects of these rapidly growing MS technologies in pandemics like COVID-19 outbreaks has been limited. Hence, this perspective gives a brief of the existing knowledge, current challenges, and opportunities for MS-based techniques as a promising avenue in studying emerging pathogen outbreaks such as COVID-19.


Assuntos
Infecções por Coronavirus/etiologia , Lipidômica/métodos , Espectrometria de Massas/métodos , Metabolômica/métodos , Pneumonia Viral/etiologia , Proteômica/métodos , Cromatografia Líquida de Alta Pressão , Técnicas de Laboratório Clínico , Infecções por Coronavirus/diagnóstico , Glicômica/métodos , Humanos , Pandemias , Reação em Cadeia da Polimerase , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
4.
Nat Commun ; 11(1): 4646, 2020 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-32938911

RESUMO

The human betacoronaviruses HKU1 and OC43 (subgenus Embecovirus) arose from separate zoonotic introductions, OC43 relatively recently and HKU1 apparently much longer ago. Embecovirus particles contain two surface projections called spike (S) and haemagglutinin-esterase (HE), with S mediating receptor binding and membrane fusion, and HE acting as a receptor-destroying enzyme. Together, they promote dynamic virion attachment to glycan-based receptors, specifically 9-O-acetylated sialic acid. Here we present the cryo-EM structure of the ~80 kDa, heavily glycosylated HKU1 HE at 3.4 Å resolution. Comparison with existing HE structures reveals a drastically truncated lectin domain, incompatible with sialic acid binding, but with the structure and function of the esterase domain left intact. Cryo-EM and mass spectrometry analysis reveals a putative glycan shield on the now redundant lectin domain. The findings further our insight into the evolution and host adaptation of human embecoviruses, and demonstrate the utility of cryo-EM for studying small, heavily glycosylated proteins.


Assuntos
Betacoronavirus/química , Betacoronavirus/fisiologia , Infecções por Coronavirus/virologia , Hemaglutininas Virais/química , Proteínas Virais de Fusão/química , Betacoronavirus/classificação , Sítios de Ligação , Domínio Catalítico , Microscopia Crioeletrônica , Glicosilação , Células HEK293 , Hemaglutininas Virais/metabolismo , Hemaglutininas Virais/ultraestrutura , Humanos , Lectinas/química , Lectinas/metabolismo , Espectrometria de Massas , Modelos Moleculares , Ácido N-Acetilneuramínico/metabolismo , Polissacarídeos/química , Domínios Proteicos , Proteínas Virais de Fusão/metabolismo , Proteínas Virais de Fusão/ultraestrutura
5.
Int Heart J ; 61(5): 1014-1021, 2020 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-32879261

RESUMO

Impaired fatty acid metabolism is associated with heart failure (HF) prognosis. However, specific changes in acylcarnitine profiles and their potential clinical value have not been well explored in patients recovering from acute decompensation.This study recruited 79 HF patients hospitalized because of acute decompensation with a left ventricular ejection fraction (LVEF) of < 40% and 51 normal controls. Patients were dichotomized into two groups, namely, the "improved (IMP) " and the "non-improved (NIMP) " groups, as defined by the changes in LVEF from baseline to 12 months after discharge. Mass spectrometry was used to quantify the acylcarnitine concentrations at baseline and 6 and 12 months after discharge. The IMP and NIMP groups contained 42 and 37 patients, respectively. At baseline, HF patients had higher plasma concentrations of specific long-, medium-, and short-chain acylcarnitines compared to normal controls. From baseline to 12 months post-discharge, the IMP group showed significant decreases in long- and short-chain acylcarnitine concentrations, but significant increases in medium-chain acylcarnitines. In the NIMP group, none of the acylcarnitines significantly decreased, and significant increases were noted in long-, medium-, and short-chain acylcarnitines. Generalized estimating equations demonstrated that nine acylcarnitines could discriminate the IMP group from the NIMP group, including three long-chain (C18:1, C16, and C16:1) and six short-chain acylcarnitines (C5, C5-OH, C4, C4:1-DC, C3, and C2). After adjusting for age, the six short-chain acylcarnitines remained significant. Changes in short-chain acylcarnitine profiles are independently associated with the improvement in cardiac systolic function after acute decompensation.


Assuntos
Carnitina/análogos & derivados , Ácidos Graxos/metabolismo , Insuficiência Cardíaca/metabolismo , Metabolômica , Idoso , Carnitina/metabolismo , Estudos de Casos e Controles , Ésteres/metabolismo , Feminino , Insuficiência Cardíaca/fisiopatologia , Insuficiência Cardíaca/terapia , Humanos , Masculino , Espectrometria de Massas , Pessoa de Meia-Idade , Prognóstico , Volume Sistólico , Sístole
6.
Zhongguo Zhong Yao Za Zhi ; 45(16): 3883-3889, 2020 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-32893585

RESUMO

Shotgun based proteomics and peptidomics analysis were used to investigate the proteins and peptides in marine traditional Chinese medicine(TCM) Sepiae Endoconcha(cuttlebone). Peptides were extracted from cuttlebone by acidified methanol, and then strong cation exchange(SCX) resin was used to enrich those peptides. Also, proteins from cuttlebone were extracted and digested by trypsin. nano-LC Q Exactive Orbitrap mass spectrometry was used to analyze proteins and peptides from cuttlebone. As a result, a total of 16 proteins and 168 peptides were identified by protein database search, and 328 peptides were identified by De novo sequencing. The identified proteins were hemocyanin, enolase, myosin, actin, calmodulin, etc., and the identified peptides were derived from actin, histone, and tubulin. All these proteins and peptides were important components in cuttlebone, which would provide important theoretical and research basis for marine TCM cuttlebone investigations.


Assuntos
Peptídeos , Proteômica , Cátions , Bases de Dados de Proteínas , Espectrometria de Massas
7.
Zhongguo Zhong Yao Za Zhi ; 45(16): 3908-3914, 2020 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-32893588

RESUMO

G-quadruplex DNA has become an important target for tumor therapy and anti-tumor development. Modern pharmacology has proved that Macleaya cordata has anti-inflammatory, antibacterial, anti-tumor and other pharmacological effects. Affinity ultrafiltration method can screen active ingredients from compounds rapidly, but G-quadruplex DNA ligands are difficult to dissociate, which is a key step in conventional ultrafiltration method. In this paper, the filtrates after ultrafiltration were determined by HPLC-MS in substitution. The peaks with 20% reduction of MS response from the incubation vs control were considered to be ligand components to G-quadruplex. Two of the peaks with the relative abundance above 30% were identified as sanguinarine(SAN) and chelerine(CHE). Their circular dichroism conformations further proved that SAN and CHE are active ligands of HT4. In addition, another two gradients with high relative abundance were identified as protopine(PRO) and allpcryprotopine(ALL). The binding rate of SAN, CHE, PRO and ALL was calculated according to the HPLC-MS results, and the results showed a consistency with that of the molecular docking method. The proposed method can be used to screen active components from mixture.


Assuntos
Quadruplex G , Ultrafiltração , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Ligantes , Espectrometria de Massas , Simulação de Acoplamento Molecular
8.
Zhongguo Zhong Yao Za Zhi ; 45(16): 3952-3960, 2020 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-32893594

RESUMO

A method of ultra-high performance liquid chromatography coupled with quadrupole/electrostatic field Obitrap high-resolution mass spectrometry(UHPLC-Q-Exactive MS) was established to comprehensively identify the metabolites of carnosic acid in rats. After oral gavage of carnosic acid CMC-Na suspension in rats, urine, plasma and feces samples were collected and pretreated by solid phase extraction(SPE). Acquity UPLC BEH C_(18 )column(2.1 mm×100 mm, 1.7 µm) was used with 0.1% formic acid solution(A)-acetonitrile(B) as the mobile phase for the gradient elution. Biological samples were analyzed by quadrupole/electrostatic field Obitrap high-resolution mass spectrometry in positive and negative ion mode. Based on the accurate molecular mass, fragment ion information, and related literature reports, a total of 28 compounds(including carnosic acid) were finally identified in rat samples. As a result, the main metabolic pathways of carnosic acid in rats are oxidation, hydroxylation, methylation, glucuronide conjugation, sulfate conjugation, S-cysteine conjugation, glutathione conjugation, demethylation, decarbonylation and their composite reactions. The study showed that the metabolism of carnosic acid in rats could be efficiently and comprehensively clarified by using UHPLC-Q-Exactive MS, providing a reference for clarifying the material basis and metabolic mechanism of carnosic acid.


Assuntos
Abietanos , Extração em Fase Sólida , Animais , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas , Ratos
9.
Wei Sheng Yan Jiu ; 49(4): 603-612, 2020 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-32928352

RESUMO

OBJECTIVE: A method based on isotope internal standard dilution was established for the determination of four polycyclic aromatic hydrocarbons(PAH4) including chrysene, benzo [a] anthracene, benzo [b] fluoranthene and benzo [a] pyrene in spicy strips sold in the markets. METHODS: The hot strips were homogenized and the target compounds were extracted with n-hexane, concentrated in vacuum, saponified and purified by solid phase extraction column, then the pretreated samples were separated by DB-EUPAH column(20 m×0. 18 mm, 0. 14 µm), detected by gas chromatography-mass spectrometry(GC-MS)and quantified by internal standard of isotope. RESULTS: The recoveries of PAH4 in different concentration levels of hot noodles were 91. 0%-103. 5%, and the relative standard deviation(RSD)was 1. 89%-6. 73%(n=6). The detection limit was 0. 30 µg/kg and the quantitative limit was 1. 0 µg/kg. The content of PAH4(sum) in 27 collected samples ranged from 1. 35 µg/kg to 11. 44 µg/kg, and the detection rate was 100%. CONCLUSION: With less solvent consumption, good purification effect and blank control, the method is simple, rapid and accurate and meets the detecting requirements of PAH4 in hot strips.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos/análise , Cromatografia Gasosa-Espectrometria de Massas , Isótopos , Espectrometria de Massas , Vácuo
10.
Biomed Environ Sci ; 33(8): 583-592, 2020 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-32933610

RESUMO

Objective: To screen the differentially expressed proteins (DEPs) in human bronchial epithelial cells (HBE) treated with atmospheric fine particulate matter (PM 2.5). Methods: HBE cells were treated with PM 2.5 samples from Shenzhen and Taiyuan for 24 h. To detect overall protein expression, the Q Exactive mass spectrometer was used. Gene ontology (GO), Kyoto encyclopedia of genes and genomes (KEGG), and Perseus software were used to screen DEPs. Results: Overall, 67 DEPs were screened in the Shenzhen sample-treated group, of which 46 were upregulated and 21 were downregulated. In total, 252 DEPs were screened in the Taiyuan sample-treated group, of which 134 were upregulated and 118 were downregulated. KEGG analysis demonstrated that DEPs were mainly enriched in ubiquitin-mediated proteolysis and HIF-1 signal pathways in Shenzhen PM 2.5 samples-treated group. The GO analysis demonstrated that Shenzhen sample-induced DEPs were mainly involved in the biological process for absorption of various metal ions and cell components. The Taiyuan PM 2.5-induced DEPs were mainly involved in biological processes of protein aggregation regulation and molecular function of oxidase activity. Additionally, three important DEPs, including ANXA2, DIABLO, and AIMP1, were screened. Conclusion: Our findings provide a valuable basis for further evaluation of PM 2.5-associated carcinogenesis.


Assuntos
Poluentes Atmosféricos/análise , Brônquios/metabolismo , Células Epiteliais/metabolismo , Expressão Gênica/efeitos dos fármacos , Material Particulado/análise , Brônquios/efeitos dos fármacos , Biologia Computacional , Células Epiteliais/efeitos dos fármacos , Humanos , Espectrometria de Massas , Tamanho da Partícula , Proteômica
11.
BMC Bioinformatics ; 21(1): 418, 2020 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-32972355

RESUMO

BACKGROUND: Mass spectrometry (MS) uses mass-to-charge ratios of measured particles to decode the identities and quantities of molecules in a sample. Interpretation of raw MS depends upon data processing algorithms that render it human-interpretable. Quantitative MS workflows are complex experimental chains and it is crucial to know the performance and bias of each data processing method as they impact accuracy, coverage, and statistical significance of the result. Creation of the ground truth necessary for quantitatively evaluating MS1-aware algorithms is difficult and tedious task, and better software for creating such datasets would facilitate more extensive evaluation and improvement of MS data processing algorithms. RESULTS: We present JS-MS 2.0, a software suite that provides a dependency-free, browser-based, one click, cross-platform solution for creating MS1 ground truth. The software retains the first version's capacity for loading, viewing, and navigating MS1 data in 2- and 3-D, and adds tools for capturing, editing, saving, and viewing isotopic envelope and extracted isotopic chromatogram features. The software can also be used to view and explore the results of feature finding algorithms. CONCLUSIONS: JS-MS 2.0 enables faster creation and inspection of MS1 ground truth data. It is publicly available with an MIT license at github.com/optimusmoose/jsms.


Assuntos
Algoritmos , Internet , Espectrometria de Massas , Humanos , Software , Interface Usuário-Computador
12.
Anticancer Res ; 40(10): 5509-5516, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32988874

RESUMO

BACKGROUND/AIM: Extracellular vesicles (EVs) can mediate drug resistance within the tumor microenvironment by delivering bioactive molecules, including proteins. Here, we performed a comparative proteomic analysis of EVs secreted by A549 lung cancer cells and their cisplatin-resistant counterparts in order to identify proteins involved in drug resistance. MATERIALS AND METHODS: Cells were co-cultivated using a transwell system to evaluate EV exchange. EVs were isolated by ultracentrifugation and analyzed using microscopy and nanoparticle tracking. EV proteome was analyzed by mass spectrometry. RESULTS: EV-mediated communication was observed between co-cultured A549 and A549/CDDP cells. EVs isolated from both cells were mainly exosome-like structures. Extracellular matrix components, cell adhesion proteins, complement factors, histones, proteasome subunits and membrane transporters were found enriched in the EVs released by cisplatin-resistant cells. CONCLUSION: Proteins identified in this work may have a relevant role in modulating the chemosensitivity of the recipient cells and could represent useful biomarkers to monitor cisplatin response in lung cancer.


Assuntos
Biomarcadores Tumorais/genética , Cisplatino/farmacologia , Neoplasias Pulmonares/tratamento farmacológico , Proteoma/genética , Células A549 , Cisplatino/efeitos adversos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Exossomos/efeitos dos fármacos , Exossomos/genética , Vesículas Extracelulares/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Espectrometria de Massas , Proteômica/métodos , Microambiente Tumoral/efeitos dos fármacos
13.
J Chromatogr A ; 1628: 461443, 2020 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-32822982

RESUMO

Sodium dodecyl sulfate (SDS) in proteomics samples needs to be removed and estimated prior to mass spectrometry (MS)-based analysis and to avoid MS ion-source contamination. Here, we describe an organic solvent free method to remove SDS using a simple apparatus that mainly consists of an agarose gel inside a 1 mL plastic micropipette tip and a voltage power supply with electrodes. A small volume of sample (e.g., 50 µL) is loaded on top of the gel and then voltage (cathode at the sample side) is applied with an acidic solution at the other end of the micropipette tip. Within 25 min, SDS was removed (e.g., ≥99% SDS in 3.5 mM SDS) and the peptides were retained in the sample solution. The strategy was compared to the commercially available and expensive Pierce spin column for the removal of SDS and recovery of peptides from a digested bovine serum albumin sample.


Assuntos
Técnicas de Química Analítica/métodos , Técnicas Eletroquímicas , Proteômica/métodos , Dodecilsulfato de Sódio/isolamento & purificação , Eletroforese em Gel de Poliacrilamida , Espectrometria de Massas , Peptídeos/química , Soroalbumina Bovina/química , Dodecilsulfato de Sódio/química
14.
J Chromatogr A ; 1628: 461448, 2020 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-32822987

RESUMO

During a screening of cyclodextrins (CDs) as chiral selectors for the separation of daclatasvir (DCV) and its enantiomer by capillary electrophoresis (CE), an unusual phenomenon for CDs was observed, that is two peaks with a plateau in between using γ-CD as chiral selector. The same result was encountered when enantiopure DCV was injected or when analyzing a sample containing enantiopure DCV and γ-CD in a CD-free background electrolyte. Peak coalescence was observed at 45°C and at a pH above 3.5. Two peaks with a plateau were also observed for DCV stereoisomers as well as a structural analog. However, only a single peak was detected if one or both amino acid moieties of DCV were lacking. Nuclear magnetic resonance (NMR) experiments including Nuclear Overhauser effect-based methods showed that in solution DCV adopted a folded conformation in which the isopropyl side chain of the valine residues pointed toward the aromatic rings of DCV. Moreover, NMR unequivocally demonstrated the simultaneous formation of DCV-γ-CD inclusion complexes with 1:1 and 2:1 stoichiometry, which was corroborated by mass spectrometry. In both complexes, DCV also adopted a folded structure. The RSSR-diastereomer of DCV as well as an analog lacking one of the amino acid moieties also formed 1:1 and 2:1 complexes with γ-CD although a plateau was only observed in the case of the RSSR-diastereomer. As shown by CE-MS, both DCV-γ-CD complexes surprisingly comigrated as the first peak, while the second migrating peak represents non-complexed DCV.


Assuntos
Imidazóis/química , gama-Ciclodextrinas/química , Eletroforese Capilar , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Conformação Molecular , Estereoisomerismo
15.
PLoS One ; 15(8): e0235421, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32756552

RESUMO

We investigated rock varnish, a thin, manganese- and iron-rich, dark surface crust, on basaltic lava flows and petroglyphs in the Owens and Rose Valleys (California) by portable X-ray fluorescence (pXRF) and femtosecond laser-ablation inductively-coupled-plasma mass spectrometry (fs-LA-ICPMS). The major element composition of the varnish was consistent with a mixture of Mn-Fe oxyhydroxides and clay minerals. As expected, it contained elevated concentrations of elements that are typically enriched in rock varnish, e.g., Mn, Pb, Ba, Ce, and Co, but also showed unusually high enrichments in U, Cu, and Th. The rare earth and yttrium (REY) enrichment pattern revealed a very strong positive cerium (Ce) anomaly and distinct negative europium (Eu) and Y anomalies. The light rare earth elements (REE) were much more strongly enriched than the heavy REY. These enrichment patterns are consistent with a formation mechanism by leaching of Mn and trace elements from aeolian dust, reprecipitation of Mn and Fe as oxyhydroxides, and scavenging of trace elements by these oxyhydroxides. We inferred accumulation rates of Mn and Fe in the varnish from their areal densities measured by pXRF and the known ages of some of the lava flow surfaces. The areal densities of Mn and Fe, as well as their accumulation rates, were comparable to our previous results from the desert of Saudi Arabia. There was a moderate dependence of the Mn areal density on the inclination of the rock surfaces, but no relationship to its cardinal orientation. We attempted to use the degree of varnish regrowth on the rock art surfaces as an estimate of their age. While an absolute dating of the petroglyphs was not possible because of the lack of suitable calibration surfaces and a considerable amount of variability, the measured degree of varnish regrowth on the various petroglyphs was consistent with chronologies based on archeological and other archaeometric techniques. In particular, our results suggest that rock art creation in the study area continued over an extended period of time, possibly starting around the Pleistocene/Holocene transition and extending into the last few centuries.


Assuntos
Argila/química , Hidróxidos/análise , Ferro/análise , Manganês/análise , California , Meio Ambiente , Monitoramento Ambiental , Espectrometria de Massas , Metais Terras Raras/análise , Espectrometria por Raios X , Propriedades de Superfície , Erupções Vulcânicas , Ítrio/análise
16.
J Chromatogr A ; 1626: 461344, 2020 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-32797824

RESUMO

The applicability of capillary zone electrophoresis (CZE) for the separation of the deamidated forms of insulin has been studied. 50 mM NH4Ac (pH=9) with 20 % v/v isopropylalcohol was found optimal for efficient separation of insulin from its even 10 deamidated forms. The developed method was efficiently applied for monitoring the degradation rate of insulin and the formation of different deamidation isoforms. Two months after the acidification more than thirty peaks can be observed in the electropherogram, because degradation products other than deamidated components were formed as well. The recorded mass spectra enabled us to assign the exact mass of the components, and thus the identification of insulin isoforms could be accomplished. We think that this study provides useful information on how the determination of several deamidation forms can be carried out with CE-MS, but the identification of the exact position of deamidation sites in the insulin molecule remains a challenge.


Assuntos
Eletroforese Capilar/métodos , Insulinas/análise , Humanos , Concentração de Íons de Hidrogênio , Espectrometria de Massas , Isoformas de Proteínas/análise , Temperatura
17.
PLoS One ; 15(8): e0236439, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32813744

RESUMO

Extracellular vesicles (EVs) in human blood are a potential source of biomarkers. To which extent anticoagulation affects their concentration, cellular origin and protein composition is largely unexplored. To study this, blood from 23 healthy subjects was collected in acid citrate dextrose (ACD), citrate or EDTA, or without anticoagulation to obtain serum. EVs were isolated by ultracentrifugation or by size-exclusion chromatography (SEC) for fluorescence-SEC. EVs were analyzed by micro flow cytometry, NTA, TEM, Western blot, and protein mass spectrometry. The plasma EV concentration was unaffected by anticoagulants, but serum contained more platelet EVs. The protein composition of plasma EVs differed between anticoagulants, and between plasma and serum. Comparison to other studies further revealed that the shared EV protein composition resembles the "protein corona" of synthetic nanoparticles incubated in plasma or serum. In conclusion, we have validated a higher concentration of platelet EVs in serum than plasma by contemporary EV methods. Anticoagulation should be carefully described (i) to enable study comparison, (ii) to utilize available sample cohorts, and (iii) when preparing/selecting biobank samples. Further, the similarity of the EV protein corona and that of nanoparticles implicates that EVs carry both intravesicular and extravesicular cargo, which will expand their applicability for biomarker discovery.


Assuntos
Biomarcadores/sangue , Proteínas Sanguíneas/isolamento & purificação , Vesículas Extracelulares/genética , Proteoma/genética , Adulto , Plaquetas/química , Proteínas Sanguíneas/genética , Feminino , Citometria de Fluxo/métodos , Voluntários Saudáveis , Humanos , Masculino , Espectrometria de Massas/métodos , Pessoa de Meia-Idade
18.
PLoS One ; 15(8): e0233820, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32804976

RESUMO

Molecular markers derived from cerebrospinal fluid (CSF) represent an accessible means of exploring the pathobiology of Huntington's disease (HD) in vivo. The endo-lysosomal/autophagy system is dysfunctional in HD, potentially contributing to disease pathogenesis and representing a potential target for therapeutic intervention. Several endo-lysosomal proteins have shown promise as biomarkers in other neurodegenerative diseases; however, they have yet to be fully explored in HD. We performed parallel reaction monitoring mass spectrometry analysis (PRM-MS) of multiple endo-lysosomal proteins in the CSF of 60 HD mutation carriers and 20 healthy controls. Using generalised linear models controlling for age and CAG, none of the 18 proteins measured displayed significant differences in concentration between HD patients and controls. This was affirmed by principal component analysis, in which no significant difference across disease stage was found in any of the three components representing lysosomal hydrolases, binding/transfer proteins and innate immune system/peripheral proteins. However, several proteins were associated with measures of disease severity and cognition: most notably amyloid precursor protein, which displayed strong correlations with composite Unified Huntington's Disease Rating Scale, UHDRS Total Functional Capacity, UHDRS Total Motor Score, Symbol Digit Modalities Test and Stroop Word Reading. We conclude that although endo-lysosomal proteins are unlikely to have value as disease state CSF biomarkers for Huntington's disease, several proteins demonstrate associations with clinical severity, thus warranting further, targeted exploration and validation in larger, longitudinal samples.


Assuntos
Proteínas do Líquido Cefalorraquidiano/metabolismo , Doença de Huntington/líquido cefalorraquidiano , Adulto , Idoso , Precursor de Proteína beta-Amiloide/líquido cefalorraquidiano , Biomarcadores/líquido cefalorraquidiano , Estudos de Casos e Controles , Cognição , Estudos Transversais , Progressão da Doença , Endossomos/metabolismo , Feminino , Proteína Ativadora de G(M2)/líquido cefalorraquidiano , Humanos , Proteína Huntingtina/genética , Doença de Huntington/genética , Doença de Huntington/psicologia , Modelos Lineares , Estudos Longitudinais , Proteína 2 de Membrana Associada ao Lisossomo/líquido cefalorraquidiano , Glicoproteínas de Membrana Associadas ao Lisossomo/líquido cefalorraquidiano , Masculino , Espectrometria de Massas/métodos , Pessoa de Meia-Idade , Análise de Componente Principal , Estudos Prospectivos , Proteínas/metabolismo , Expansão das Repetições de Trinucleotídeos
19.
PLoS One ; 15(8): e0237612, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32790731

RESUMO

Seventeen glass vessels and twenty glass beads recovered from the excavations at the ancient city of Malindi and the archaeological site of Mambrui in Kenya, east Africa were analysed using electron probe microanalysis (EPMA) and laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS). The results show that all of the glass samples are soda-lime-silica glass. They belong to the high alumina -plant ash glass type, characterised by high alumina and relatively low calcium contents, widely distributed in eastern (10th- 16th centuries AD) and southern Africa (13th - 15th centuries AD), Central Asia (9th- 14th centuries AD) and southeast Asia (12th- 13th centuries AD), made with plant ashes and sands. This is an understudied glass type for which previous research has indicated there were three types. When compared with published research on such glasses using Zr, Ti, Ba, Cr, La, Li, Cs, Na2O, MgO and CaO we have identified at least four different compositional groups of v-Na-Al glass: Types A, B, C and D. By comparing the results with contemporary v-Na-Al glass vessels and beads from Central Asia, Africa, and southeast Asia we show that most of the Malindi and Mambrui glass share similar characteristics to the compositions of Mapungubwe Oblate and some of the Madagascar glass beads from southern Africa. They belong to Type A v-Na-Al glass which is characterised by an elevated level of Ti and Ba and a relatively high ratios of Cr/La, relatively low Zr concentrations and low ratios of Zr/Ti. Differences in Zr, Li, MgO and Na2O concentrations in Type A glass indicates that there are subgroups which might derive from different glass workshop(s) specialising in Type A v-Na-Al glass production. Comparison with the chemical compositions of glass from Ghazni, Afghanistan and Termez, Uzbekistan, and by using lead isotope analysis, we suggest v-Na-Al glass was manufactured in Central Asia and possibly worked into vessels and beads there.


Assuntos
Compostos de Cálcio/química , Vidro/química , Óxidos/química , Plantas/química , Dióxido de Silício/química , Hidróxido de Sódio/química , Oligoelementos/análise , Oligoelementos/história , África Oriental , Óxido de Alumínio , Arqueologia , História do Século XV , História do Século XVI , Oceano Índico , Marcação por Isótopo/métodos , Quênia , Espectrometria de Massas
20.
Yakugaku Zasshi ; 140(8): 1035-1040, 2020.
Artigo em Japonês | MEDLINE | ID: mdl-32741861

RESUMO

For many of the novel antiepileptics, immunoassays, used for routine therapeutic drug monitoring (TDM), cannot be used. We could monitor eight novel antiepileptics using an LC/MS method since July 2017. The purpose of this study was to evaluate the significant changes associated with the transition from outsourcing to in-hospital monitoring of novel antiepileptics. The number of measurements of novel antiepileptics was significantly increased during the first (p<0.01) and second (p<0.001) years of in-hospital monitoring as compared to that one year prior to in-hospital monitoring which was outsourced. The proportion of measurements of novel antiepileptics to all antiepileptics was 19.7%, 31.1%, and 38.4% during outsourcing, and first, and second years of in-hospital monitoring, respectively. The measurement cost was significantly reduced during the first (p<0.001) and second (p<0.001) years of in-hospital monitoring as compared to that during outsourcing. In addition, the revenue from TDM of antiepileptic drugs was significantly increased during the first (p<0.05) and second (p<0.01) years of in-hospital monitoring as compared with that during outsourcing. In conclusion, the switch from outsourcing to in-hospital monitoring led to an increase in the number of orders, a reduction in the measurement-related expenses of novel antiepileptics, and an increase in the revenue from TDM of antiepileptic drugs, which could promote the proper use of novel antiepileptics through TDM.


Assuntos
Anticonvulsivantes , Monitoramento de Medicamentos/métodos , Monitoramento de Medicamentos/estatística & dados numéricos , Serviços Terceirizados/estatística & dados numéricos , Serviço de Farmácia Hospitalar/estatística & dados numéricos , Cromatografia Líquida , Monitoramento de Medicamentos/economia , Humanos , Renda/estatística & dados numéricos , Espectrometria de Massas , Fatores de Tempo
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