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1.
Front Immunol ; 15: 1355824, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38799447

RESUMEN

Objectives: IL26 levels are elevated in the blood and synovial fluid of patients with inflammatory arthritis. IL26 can be produced by Th17 cells and locally within joints by tissue-resident cells. IL26 induces osteoblast mineralization in vitro. As osteoproliferation and Th17 cells are important factors in the pathogenesis of axial spondyloarthritis (axSpA), we aimed to clarify the cellular sources of IL26 in spondyloarthritis. Methods: Serum, peripheral blood mononuclear cells (n = 15-35) and synovial tissue (n = 3-9) of adult patients with axSpA, psoriatic arthritis (PsA) and rheumatoid arthritis (RA) and healthy controls (HCs, n = 5) were evaluated by ELISA, flow cytometry including PrimeFlow assay, immunohistochemistry and immunofluorescence and quantitative PCR. Results: Synovial tissue of axSpA patients shows significantly more IL26-positive cells than that of HCs (p < 0.01), but numbers are also elevated in PsA and RA patients. Immunofluorescence shows co-localization of IL26 with CD68, but not with CD3, SMA, CD163, cadherin-11, or CD90. IL26 is elevated in the serum of RA and PsA (but not axSpA) patients compared with HCs (p < 0.001 and p < 0.01). However, peripheral blood CD4+ T cells from axSpA and PsA patients show higher positivity for IL26 in the PrimeFlow assay compared with HCs. CD4+ memory T cells from axSpA patients produce more IL26 under Th17-favoring conditions (IL-1ß and IL-23) than cells from PsA and RA patients or HCs. Conclusion: IL26 production is increased in the synovial tissue of SpA and can be localized to CD68+ macrophage-like synoviocytes, whereas circulating IL26+ Th17 cells are only modestly enriched. Considering the osteoproliferative properties of IL26, this offers new therapeutic options independent of Th17 pathways.


Asunto(s)
Antígenos CD , Artritis Psoriásica , Interleucinas , Sinoviocitos , Humanos , Artritis Psoriásica/inmunología , Artritis Psoriásica/metabolismo , Sinoviocitos/metabolismo , Sinoviocitos/inmunología , Sinoviocitos/patología , Masculino , Adulto , Femenino , Antígenos CD/metabolismo , Interleucinas/metabolismo , Interleucinas/sangre , Persona de Mediana Edad , Antígenos de Diferenciación Mielomonocítica/metabolismo , Espondiloartritis Axial/inmunología , Células Th17/inmunología , Células Th17/metabolismo , Membrana Sinovial/inmunología , Membrana Sinovial/metabolismo , Membrana Sinovial/patología , Articulaciones/patología , Articulaciones/inmunología , Articulaciones/metabolismo , Artritis Reumatoide/inmunología , Artritis Reumatoide/metabolismo , Artritis Reumatoide/sangre , Artritis Reumatoide/patología
2.
Phys Med Biol ; 68(24)2023 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-37939402

RESUMEN

Objective.To investigate the influence of different versions of the Monte Carlo codesgeant4 andflukaon the calculation of overall response functionsfQof air-filled ionization chambers in clinical proton beams.Approach. fQfactors were calculated for six plane-parallel and four cylindrical ionization chambers withgeant4 andfluka. These factors were compared to already published values that were derived using older versions of these codes.Main results.Differences infQfactors calculated with different versions of the same Monte Carlo code can be up to ∼1%. Especially forgeant4, the updated version leads to a more pronounced dependence offQon proton energy and to smallerfQfactors for high energies.Significance.Different versions of the same Monte Carlo code can lead to differences in the calculation offQfactors of up to ∼1% without changing the simulation setup, transport parameters, ionization chamber geometry modeling, or employed physics lists. These findings support the statement that the dominant contributor to the overall uncertainty of Monte Carlo calculatedfQfactors are type-B uncertainties.


Asunto(s)
Protones , Radiactividad , Radiometría/métodos , Simulación por Computador , Método de Montecarlo
3.
J Am Soc Mass Spectrom ; 33(12): 2203-2214, 2022 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-36371691

RESUMEN

Ultrahigh resolution mass spectrometry (UHR-MS) coupled with direct infusion (DI) electrospray ionization offers a fast solution for accurate untargeted profiling. Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometers have been shown to produce a wealth of insights into complex chemical systems because they enable unambiguous molecular formula assignment even if the vast majority of signals is of unknown identity. Interlaboratory comparisons are required to apply this type of instrumentation in quality control (for food industry or pharmaceuticals), large-scale environmental studies, or clinical diagnostics. Extended comparisons employing different FT-ICR MS instruments with qualitative direct infusion analysis are scarce since the majority of detected compounds cannot be quantified. The extent to which observations can be reproduced by different laboratories remains unknown. We set up a preliminary study which encompassed a set of 17 laboratories around the globe, diverse in instrumental characteristics and applications, to analyze the same sets of extracts from commercially available standard human blood plasma and Standard Reference Material (SRM) for blood plasma (SRM1950), which were delivered at different dilutions or spiked with different concentrations of pesticides. The aim of this study was to assess the extent to which the outputs of differently tuned FT-ICR mass spectrometers, with different technical specifications, are comparable for setting the frames of a future DI-FT-ICR MS ring trial. We concluded that a cluster of five laboratories, with diverse instrumental characteristics, showed comparable and representative performance across all experiments, setting a reference to be used in a future ring trial on blood plasma.

4.
Anal Chem ; 94(21): 7536-7544, 2022 05 31.
Artículo en Inglés | MEDLINE | ID: mdl-35576165

RESUMEN

Bio-oils are precursors for biofuels but are highly corrosive necessitating further upgrading. Furthermore, bio-oil samples are highly complex and represent a broad range of chemistries. They are complex mixtures not simply because of the large number of poly-oxygenated compounds but because each composition can comprise many isomers with multiple functional groups. The use of hyphenated ultrahigh-resolution mass spectrometry affords the ability to separate isomeric species of complex mixtures. Here, we present for the first time, the use of this powerful analytical technique combined with chemical reactivity to gain greater insights into the reactivity of the individual isomeric species of bio-oils. A pyrolysis bio-oils and its esterified bio-oil were analyzed using gas chromatography coupled to Fourier transform ion cyclotron resonance mass spectrometry, and in-house software (KairosMS) was used for fast comparison of the hyphenated data sets. The data revealed a total of 10,368 isomers in the pyrolysis bio-oil and an increase to 18,827 isomers after esterification conditions. Furthermore, the comparison of the isomeric distribution before and after esterification provide new light on the reactivities within these complex mixtures; these reactivities would be expected to correspond with carboxylic acid, aldehyde, and ketone functional groups. Using this approach, it was possible to reveal the increased chemical complexity of bio-oils after upgrading and target detection of valuable compounds within the bio-oils. The combination of chemical reactions alongside with in-depth molecular characterization opens a new window for the understanding of the chemistry and reactivity of complex mixtures.


Asunto(s)
Aceites de Plantas , Polifenoles , Biocombustibles/análisis , Biomasa , Mezclas Complejas , Cromatografía de Gases y Espectrometría de Masas , Calor , Aceites de Plantas/química , Polifenoles/química
5.
Molecules ; 27(7)2022 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-35408438

RESUMEN

Recently published work has reported the development and application of a bottom-up proteomic approach to distinguish between human and animal blood (down to animal species level), by rapid screening using Matrix Assisted Laser Desorption Ionisation Mass Spectrometry (MALDI MS). In that study, it was additionally observed that intravenous animal blood exhibits different spectral profiles from blood collected within the animal chest cavity as well as from the diluted blood collected within packets of meat. In this follow-up study we explored the resulting hypothesis that, depending on how blood is shed or collected, protein biomarker profiles vary to the extent of systematically permitting a distinction between possible sources of blood (for example, flesh wound versus packaged meat). This intelligence may be important in reconstructing the dynamics of the crime. The combination of statistical analysis and tandem mass spectrometry has yielded additional animal blood markers as well as confirming the ability to correctly determine the animal species from which blood derived, regardless of the retailer selling it (amongst the five investigated). These data confirm the initial hypothesis and demonstrate the opportunity for the proteomics-MALDI combined approach to provide additional intelligence to the investigation of violent crimes when examining blood evidence.


Asunto(s)
Proteómica , Espectrometría de Masas en Tándem , Animales , Biomarcadores/metabolismo , Estudios de Seguimiento , Medicina Legal , Proteómica/métodos , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos
6.
Anal Chem ; 94(3): 1760-1768, 2022 01 25.
Artículo en Inglés | MEDLINE | ID: mdl-35026111

RESUMEN

Liquid chromatography-mass spectrometry (LC-MS) is the main workhorse of metabolomics owing to its high degree of analytical sensitivity and specificity when measuring diverse chemistry in complex biological samples. LC-MS-based metabolic profiling of human urine, a biofluid of primary interest for clinical and biobank studies, is not widely considered to be compromised by the presence of endogenous interferences and is often accomplished using a simple "dilute-and-shoot" approach. Yet, it is our experience that broad obscuring signals are routinely observed in LC-MS metabolic profiles and represent interferences that lack consideration in the relevant metabolomics literature. In this work, we chromatographically isolated the interfering metabolites from human urine and unambiguously identified them via de novo structure elucidation as two separate proline-containing dipeptides: N,N,N-trimethyl-l-alanine-l-proline betaine (l,l-TMAP) and N,N-dimethyl-l-proline-l-proline betaine (l,l-DMPP), the latter reported here for the first time. Offline LC-MS/MS, magnetic resonance mass spectrometry (MRMS), and nuclear magnetic resonance (NMR) spectroscopy were essential components of this workflow for the full chemical and spectroscopic characterization of these metabolites and for establishing the coexistence of cis and trans isomers of both dipeptides in solution. Analysis of these definitive structures highlighted intramolecular ionic interactions as responsible for slow interconversion between these isomeric forms resulting in their unusually broad elution profiles. Proposed mitigation strategies, aimed at increasing the quality of LC-MS-based urine metabolomics data, include modification of column temperature and mobile-phase pH to reduce the chromatographic footprint of these dipeptides, thereby reducing their interfering effect on the underlying metabolic profiles. Alternatively, sample dilution and internal standardization methods may be employed to reduce or account for the observed effects of ionization suppression on the metabolic profile.


Asunto(s)
Metabolómica , Espectrometría de Masas en Tándem , Cromatografía Liquida/métodos , Humanos , Espectroscopía de Resonancia Magnética/métodos , Metaboloma , Metabolómica/métodos , Espectrometría de Masas en Tándem/métodos
7.
J Pharm Biomed Anal ; 209: 114538, 2022 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-34929567

RESUMEN

The 3C-like protease (3CLpro) of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is essential to the virus life cycle and is supposed to be a potential target for the treatment of coronaviral infection. Traditional Chinese medicines (TCMs) have played an impressive role in the treatment of COVID-19 in China. The effectiveness of TCM formulations prompts scientists to take continuous effort on searching for bioactive small molecules from the ancient resources. Herein, we developed a native mass spectrometry-based affinity-selection method for rapid screening of active small molecules from crude herbal extracts applied for COVID-19 therapy. Six common herbs named Lonicera japonica, Scutellaria baicalensis, Forsythia suspensa, Glycyrrhiza uralensis, Cirsium japonicum, and Andrographis paniculata were investigated. After preliminary separation of the crude extracts, the fractions were incubated with 3CLpro. A native MS-based affinity screening assay was then conducted to search for the protein-ligand complexes. A UHPLC-Q/TOF-MS with UNIFI data acquisition and data processing software was applied to identify the hit compounds. Standard compounds were used to verify the outcomes. Among the 16 hits, three flavonoids, baicalein, scutellarein and ganhuangenin, were identified as potential noncovalent inhibitors against 3CLpro with IC50 values of 0.94, 3.02, and 0.84 µM, respectively. Their binding affinities were further characterized by native MS, with Kd values being 1.43, 3.85, and 1.09 µM, respectively. Overall, we established an efficient native MS-based strategy for discovering 3CLpro ligands from crude mixtures, which supplies a potential strategy of small molecule lead discovery from TCMs.


Asunto(s)
COVID-19 , SARS-CoV-2 , Andrographis paniculata , Antivirales/farmacología , Humanos , Simulación del Acoplamiento Molecular , Péptido Hidrolasas , Inhibidores de Proteasas/farmacología
8.
Phys Med Biol ; 66(24)2021 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-34844221

RESUMEN

In particle therapy of lung tumors, modulating effects on the particle beam may occur due to the microscopic structure of the lung tissue. These effects are caused by the heterogeneous nature of the lung tissue and cannot be completely taken into account during treatment planning, because these micro structures are too small to be fully resolved in the planning CT. In several publications, a new material parameter called modulation power (Pmod) was introduced to characterize the effect. For various artificial lung surrogates, this parameter was measured and published by other groups and ranges up to approximately 1000µm. Studies investigating the influence of the modulation power on the dose distribution during irradiation are using this parameter in the rang of 100-800µm. More precise measurements forPmodon real lung tissue have not yet been published. In this work, the modulation power of real lung tissue was measured using porcine lungs in order to produce more reliable data ofPmodfor real lung tissue. For this purpose,ex-vivoporcine lungs were frozen in a ventilated state and measurements in a carbon ion-beam were performed. Due to the way the lungs were prepared and transferred to a solid state, the lung structures that modulate the beam could also be examined in detail using micro CT imaging. An optimization of the established methods of measuring the modulation power, which takes better account of the typical structures within lung tissue, was developed as well.


Asunto(s)
Neoplasias Pulmonares , Terapia de Protones , Animales , Pulmón/efectos de la radiación , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/radioterapia , Terapia de Protones/métodos , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por Computador/métodos , Porcinos
9.
Med Phys ; 48(12): 8052-8061, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34668589

RESUMEN

PURPOSE: To predict and mitigate for the degradation in physical and biologically effective dose distributions of particle beams caused by microscopic heterogeneities in lung tissue. MATERIALS AND METHODS: The TRiP98 treatment planning system was adapted to account for the beam-modulating effect of heterogeneous lung tissue in physical and biological inverse treatment planning. The implementation employs an analytical model that derives the degradation from the established "modulation power" parameter P mod and the total water-equivalent thickness of lung parenchyma traversed by the beam. Beam modulation was reproduced through an on-the-fly convolution of the reference Bragg curve with Gaussian kernels depending on the modulation power of lung tissue (upstream). For biological doses, the degradation was determined by modulating dose-averaged α , ß , and LET distributions. Carbon SOBP measurements behind lung substitute material were performed to validate the code. The implementation was then applied to a phantom and patient case. RESULTS: Experimental results show the passage through a 20-cm Gammex LN300 slab led to a decrease in target coverage and broadening of the SOBP distal fall-off. However, dose coverage was regained through optimization. A good agreement between calculated and measured SOBPs was also found. In addition, a patient case study revealed a 3.2% decrease in D 95 from degradation ( P mod = 450 µ m), which was reduced to a 0.4% difference after optimization. Furthermore, widening of the RBE distribution beyond the target distal edge was observed. This implies an increased degradation in the biological dose, which could be harmful to healthy tissues distal to the target. CONCLUSIONS: This is the first implementation capable of compensating for lung dose perturbations, which is more effective than margin extensions. A larger patient study is needed to examine the observed modulation in the RBE distribution and judge the clinical relevance also in IMPT, where margins might prove insufficient to recover target coverage.


Asunto(s)
Radioterapia de Iones Pesados , Terapia de Protones , Algoritmos , Humanos , Pulmón/diagnóstico por imagen , Fantasmas de Imagen , Planificación de la Radioterapia Asistida por Computador , Efectividad Biológica Relativa
10.
Phys Med Biol ; 66(17)2021 08 27.
Artículo en Inglés | MEDLINE | ID: mdl-34378546

RESUMEN

Purpose.To provide Monte Carlo calculated beam quality correction factors (kQ) for monoenergetic proton beams using the Monte Carlo codefluka.Materials and methods.The Monte Carlo codeflukawas used to calculate the dose absorbed in a water-filled reference volume and the air-filled cavities of six plane-parallel and four cylindrical ionization chambers. The chambers were positioned at the entrance region of monoenergetic proton beams with energies between 60 and 250 MeV. Based on these dose values,fQas well askQfactors were calculated whilefQ0factors were taken from Andreoet al(2020Phys. Med. Biol.65095011).Results. kQfactors calculated in this work were found to agree with experimentally determinedkQfactors on the 1%-level, with only two exceptions with deviations of 1.4% and 1.9%. The comparison offQfactors calculated usingflukawithfQfactors calculated using the Monte Carlo codesgeant4 andpenhshowed a general good agreement for low energies, while differences for higher energies were pronounced. For high energies, in most cases the Monte Carlo codesflukaandgeant4 lead to comparable results while thefQfactors calculated withpenhare larger.Conclusion.flukacan be used to calculatekQfactors in clinical proton beams. The divergence of Monte Carlo calculatedkQfactors for high energies suggests that the role of nuclear interaction models implemented in the different Monte Carlo codes needs to be investigated in more detail.


Asunto(s)
Protones , Método de Montecarlo , Radiactividad , Radiometría , Efectividad Biológica Relativa
11.
Phys Med Biol ; 66(18)2021 09 07.
Artículo en Inglés | MEDLINE | ID: mdl-34298533

RESUMEN

To treat lung tumours with particle therapy, different additional tasks and challenges in treatment planning and application have to be addressed thoroughly. One of these tasks is the quantification and consideration of the Bragg peak (BP) degradation due to lung tissue: as lung is an heterogeneous tissue, the BP is broadened when particles traverse the microscopic alveoli. These are not fully resolved in clinical CT images and thus, the effect is not considered in the dose calculation. In this work, a correlation between the CT histograms of heterogeneous material and the impact on the BP curve is presented. Different inorganic materials were scanned with a conventional CT scanner and additionally, the BP degradation was measured in a proton beam and was then quantified. A model is proposed that allows an estimation of the modulation power by performing a histogram analysis on the CT scan. To validate the model for organic samples, a second measurement series was performed with frozen porcine lunge samples. This allows to investigate the possible limits of the proposed model in a set-up closer to clinical conditions. For lung substitutes, the agreement between model and measurement is within ±0.05 mm and for the organic lung samples, within ±0.15 mm. This work presents a novel, simple and efficient method to estimate if and how much a material or a distinct region (within the lung) is degrading the BP on the basis of a common clinical CT image. Up until now, only a direct in-beam measurement of the region or material of interest could answer this question.


Asunto(s)
Terapia de Protones , Animales , Pulmón/diagnóstico por imagen , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por Computador , Porcinos , Tomografía Computarizada por Rayos X
12.
Analyst ; 146(13): 4290-4302, 2021 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-34105523

RESUMEN

Over the past seven years Matrix Assisted Laser Desorption Ionisation Mass Spectrometry Profiling (MALDI MSP) and Imaging (MALDI MSI) have proven to be feasible tools for the detection of blood and its provenance in stains and fingermarks. However, whilst this capability as a confirmatory test addresses the primary questions at the scene of a violent crime, additional intelligence recoverable from blood can also prove important for investigations. A DNA profile is the most obvious and important example of such intelligence; however, it is not always suitable for identification purposes, depending on quantity, age and environmental conditions. Proteins are much more stable and determining the presence of haemoglobin variants in blood recovered at a crime scene may provide associative and possibly corroborating evidence on the presence of an individual at a particular location. This evidence gains more incriminatory value, the lower the incidence of the variant in a certain geographical area or population and may contribute to narrowing down the pool of suspects. In this study, a MALDI based mass spectrometric method has been developed and tested on six haemoglobin variants for their fast and reliable identification and mapping in blood fingermarks.


Asunto(s)
Colorantes , Pruebas Hematológicas , Hemoglobinas/análisis , Hemoglobinas/genética , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Coloración y Etiquetado
13.
Front Public Health ; 8: 558226, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33102421

RESUMEN

Edible vegetable oils comprise integral components of humans' daily diet during the lifetime. Therefore, they constitute a central part of dietary-exposome, which among other factors regulates human health. In particular, the regular consumption of olive oil (OO) has been largely accepted as a healthy dietary pattern. Responsible for its recognition as a superior edible oil is its exceptional aroma and flavor. Its unique composition is characterized by high levels of monounsaturated fatty acids and the presence of minor constituents with important biological properties, such as the so-called OO polyphenols. Being a high added value product, OO suffers from extensive fraud and adulteration phenomena. However, its great chemical complexity, variability, and the plethora of parameters affecting OO composition hamper significantly the selection of the absolute criteria defining quality and authenticity, and a reliable and robust methodology is still unavailable. In the current study, Flow Injection Analysis-Magnetic Resonance Mass Spectrometry (FIA-MRMS) was investigated under a metabolic profiling concept for the analysis of Greek Extra Virgin Olive Oils (EVOO). More than 200 monovarietal (Koroneiki) EVOO samples were collected from the main Greek OO producing regions and investigated. Both intact oil and the corresponding polyphenols were analyzed in fast analysis time of 2 and 8 min, respectively. In parallel, an LC-Orbitrap MS platform was used to verify the efficiency of the method as well as a tool to increase the identification confidence of the proposed markers. Based on the results, with FIA-MRMS, comparable and improved projection and prediction models were generated in comparison to those of the more established LC-MS methodology. With FIA-MRMS more statistically significant compounds and chemical classes were identified as quality and authenticity markers, associated with specific parameters, i.e. geographical region, cultivation practice, and production procedure. Furthermore, it was possible to monitor both lipophilic and hydrophilic compounds with a single analysis. To our knowledge, this approach is among the few studies in which two FT-MS platforms combining LC and FIA methods were integrated to provide solutions to quality control aspects of OO. Moreover, both lipophilic and hydrophilic components are analyzed together, providing a holistic quality control workflow for OO.


Asunto(s)
Análisis de Inyección de Flujo , Cromatografía Liquida , Grecia , Humanos , Espectrometría de Masas , Aceite de Oliva/análisis
14.
J Am Soc Mass Spectrom ; 31(10): 2025-2034, 2020 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-32857936

RESUMEN

A major bottleneck in metabolomics is the annotation of a molecular formula as a first step to a tentative structure assignment of known and unknown metabolites. The direct observation of an isotopic fine structure (IFS) provides the ability to confidently assign an unknown's molecular formula out of a complex mass spectrum. However, the majority of mass spectrometers deployed for metabolomic studies do not have sufficient resolving power and high-fidelity isotope ratios in the mass range of interest to determine molecular formulas from IFS data. To increase the number of unknowns for which IFS can be determined, a segmented "boxcar" approach using a selection quadrupole as a broadband mass filter is used. In this longer, enhanced dynamic range discovery experiment, selected ions in a specific mass range are accumulated before detection by the analyzer cell. The mass filter window is then moved across the entire mass range resulting in a composite mass spectrum covering the m/z range of interest for phenomics research. The effectiveness of the FIA-CASI-FTMS workflow utilizing IFS for molecular formula assignment is realized with the implementation of the dynamically harmonized cell, which distinguishes the approach from other segmented workflows because of the analytical properties of the cell. The discovery approach was applied to a human plasma sample to confidently assign an unknown molecular formula as part of the quest to illuminate its metabolic "dark matter" via high-fidelity IFS ratio determinations. The FIA-CASI-FTMS workflow showed a 2.6-fold increase in both matching with the Human Metabolome Database and an increase in the IFS pattern.


Asunto(s)
Espectrometría de Masas/métodos , Metaboloma , Metabolómica/métodos , Bases de Datos Factuales , Humanos , Isótopos/análisis , Isótopos/metabolismo , Plasma/química , Plasma/metabolismo
15.
Chemistry ; 26(53): 12180-12187, 2020 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-32578918

RESUMEN

Geodesic nitrogen-containing graphene fragments are interesting candidates for various material applications, but the available synthetic protocols, which need to overcome intrinsic strain energy during the formation of the bowl-shaped skeletons, are often incompatible with heteroatom-embedded structures. Through this mass spectrometry-based gas-phase study, we show by means of collision-induced dissociation experiments and supported by density functional theory calculations, the first evidence for the formation of a porphyrin-embedded conical nanocarbon. The influences of metalation and functionalization of the used tetrabenzoporphyrins have been investigated, which revealed different cyclization efficiencies, different ionization possibilities, and a variation of the dissociation pathway. Our results suggest a stepwise process for HF elimination from the fjord region, which supports a selective pathway towards bent nitrogen-containing graphene fragments.

16.
Food Res Int ; 133: 109209, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32466948

RESUMEN

A cocoa bean fermentation series, comprising bean samples taken every 24 h of a seven-day cocoa fermentation was analyzed by ultra-high-resolution mass spectrometry using the ESI-FT-ICR technique. Data were acquired in both positive and negative ion mode. At early fermentation times around 2000 signals could be resolved raising to a maximum of 8000 signals in each ion mode towards the end of the fermentation. Molecular formulae were assigned to a large number of observed peaks leading to ion statistics classifying cocoa constituents according elemental composition. Time dependent van Krevelen diagrams were constructed allowing the tracking of chemical changes in bean composition. In particular, the number of CHON compounds assigned to short peptides and their derivatives were shown to undergo significant chemical transformations. Theoretical MS data bases were constructed containing all possible peptides up to a length of ten amino acids and putative derivatives expected to be formed during microbial fermentation. Experimental m/z values were compared to these databases and conclusions drawn with respect to the composition of fermenting beans with tentative fermentation products suggested.


Asunto(s)
Cacao , Espectrometría de Masa por Ionización de Electrospray , Aminoácidos , Fermentación , Péptidos
17.
Eur Radiol ; 30(2): 1041-1044, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31529250

RESUMEN

OBJECTIVES: To assess the value of a T1-3D black-blood turbo spin echo (TSE) sequence for the diagnosis of abdominal large vessel vasculitis (LVV). MATERIALS AND METHODS: The study included 20 patients with abdominal LVV and 17 controls, who underwent a 3T-MRI scan using a modified T1-3D volumetric isotropic TSE acquisition and a segmented T1-3D turbo field echo sequence (T1-mVISTA/T1-eTHRIVE). Two radiologists independently analyzed the aorta for concentric contrast enhancement, concentric wall thickening, image quality, and flow artifact intensity (CCE/CWT/IQ/FAI; 4-point scales). The mean aortic wall thickness (MAWT) in post-contrast T1-mVISTA was compared between patients and controls. RESULTS: IQ of T1-mVISTA was rated good to excellent in 91.5% of 282 evaluated vessel segments with no or minor FAI present in 85.5%. The inter-observer reproducibility for the identification of CCE/CWT on T1-mVISTA was 0.92 and 0.93 (p < 0.001). The distribution of segmental inflammation in T1-mVISTA significantly correlated with T1-eTHRIVE (CCE, κ = 0.768; CWT, κ = 0.715; p < 0.001), resulting in a sensitivity, specificity, and positive predictive value of 100%, 81.3%, and 83.3%. The MAWT significantly differed between patients and controls (3.29 ± 0.81 vs. 2.24 ± 0.45 mm; p < 0.001). CONCLUSIONS: T1-mVISTA enables the evaluation of the MAWT and allows the detection of abdominal LVV. KEY POINTS: • 3D T1w-mVISTA accurately depicted the large abdominal vessels. • 3D T1w-mVISTA enables accurate measurements of the abdominal aortic wall thickness. • 3D T1w-mVISTA is useful for the detection of abdominal LVV.


Asunto(s)
Imagen por Resonancia Magnética/métodos , Vasculitis/diagnóstico por imagen , Abdomen/irrigación sanguínea , Abdomen/diagnóstico por imagen , Adulto , Anciano , Aorta Abdominal/diagnóstico por imagen , Aortitis/diagnóstico por imagen , Artefactos , Femenino , Humanos , Imagenología Tridimensional/métodos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
18.
Exp Clin Endocrinol Diabetes ; 127(10): 685-690, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31158898

RESUMEN

OBJECTIVE: Cushing's syndrome is a rare disease characterized by clinical features that show morphological similarity with the metabolic syndrome. Distinguishing these diseases in clinical practice is challenging. We have previously shown that computer vision technology can be a potentially useful diagnostic tool in Cushing's syndrome. In this follow-up study, we addressed the described problem by increasing the sample size and including controls matched by body mass index. METHODS: We enrolled 82 patients (22 male, 60 female) and 98 control subjects (32 male, 66 female) matched by age, gender and body-mass-index. The control group consisted of patients with initially suspected, but biochemically excluded Cushing's syndrome. Standardized frontal and profile facial digital photographs were acquired. The images were analyzed using specialized computer vision and classification software. A grid of nodes was semi-automatically placed on disease-relevant facial structures for analysis of texture and geometry. Classification accuracy was calculated using a leave-one-out cross-validation procedure with a maximum likelihood classifier. RESULTS: The overall correct classification rates were 10/22 (45.5%) for male patients and 26/32 (81.3%) for male controls, and 34/60 (56.7%) for female patients and 43/66 (65.2%) for female controls. In subgroup analyses, correct classification rates were higher for iatrogenic than for endogenous Cushing's syndrome. CONCLUSION: Regarding the advanced problem of detecting Cushing's syndrome within a study sample matched by body mass index, we found moderate classification accuracy by facial image analysis. Classification accuracy is most likely higher in a larger sample with healthy control subjects. Further studies might pursue a more advanced analysis and classification algorithm.


Asunto(s)
Algoritmos , Síndrome de Cushing/diagnóstico , Diagnóstico por Computador , Procesamiento de Imagen Asistido por Computador , Fotograbar , Adulto , Anciano , Estudios Transversales , Síndrome de Cushing/clasificación , Síndrome de Cushing/patología , Cara , Femenino , Humanos , Masculino , Persona de Mediana Edad
19.
Anal Chem ; 91(14): 8873-8882, 2019 07 16.
Artículo en Inglés | MEDLINE | ID: mdl-31188566

RESUMEN

Annotation and identification of metabolite biomarkers is critical for their biological interpretation in metabolic phenotyping studies, presenting a significant bottleneck in the successful implementation of untargeted metabolomics. Here, a systematic multistep protocol was developed for the purification and de novo structural elucidation of urinary metabolites. The protocol is most suited for instances where structure elucidation and metabolite annotation are critical for the downstream biological interpretation of metabolic phenotyping studies. First, a bulk urine pool was desalted using ion-exchange resins enabling large-scale fractionation using precise iterations of analytical scale chromatography. Primary urine fractions were collected and assembled into a "fraction bank" suitable for long-term laboratory storage. Secondary and tertiary fractionations exploited differences in selectivity across a range of reversed-phase chemistries, achieving the purification of metabolites of interest yielding an amount of material suitable for chemical characterization. To exemplify the application of the systematic workflow in a diverse set of cases, four metabolites with a range of physicochemical properties were selected and purified from urine and subjected to chemical formula and structure elucidation by respective magnetic resonance mass spectrometry (MRMS) and NMR analyses. Their structures were fully assigned as tetrahydropentoxyline, indole-3-acetic-acid-O-glucuronide, p-cresol glucuronide, and pregnanediol-3-glucuronide. Unused effluent was collected, dried, and returned to the fraction bank, demonstrating the viability of the system for repeat use in metabolite annotation with a high degree of efficiency.


Asunto(s)
Biomarcadores/orina , Metabolómica/métodos , Orina/química , Biomarcadores/metabolismo , Cromatografía Líquida de Alta Presión/métodos , Femenino , Humanos , Masculino , Espectrometría de Masas/métodos , Metaboloma
20.
Clin Exp Rheumatol ; 37 Suppl 121(6): 35-42, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30943130

RESUMEN

OBJECTIVES: Autonomic dysfunction (AD) has been described in various chronic inflammatory diseases. Studies of AD in patients with familial Mediterranean fever (FMF) are inconclusive. We aimed to assess AD in a cohort of FMF patients. METHODS: Signs and symptoms of AD were investigated in patients with FMF and compared to age and gender matched healthy controls. Symptoms of AD were assessed by COMPASS-31, a validated questionnaire to evaluate orthostatic, vasomotor, secretomotor, gastrointestinal, pupillomotor and bladder function domains. Assessment of objective AD comprised heart rate variability during deep breathing, skin conductance changes during mental arithmetic, blood pressure response to pain and dynamic infrared pupillometry. RESULTS: 25 patients and 25 healthy controls were included and evaluated by COMPASS-31 and objective testing of AD. FMF patients had higher median COMPASS-31 total scores than controls (23.7 vs. 1.6, p=0.024). Significant differences were also found in the secretomotor and gastrointestinal sub-domains (4.2 vs. 0.0; p<0.001 and 8.0 vs. 0.0; p=0.004, respectively). Symptoms of autonomic dysfunction were correlated with patient reported global disease activity (r=0.71; p<0.001) and pain level (r=0.68; p<0.001). There were no differences in heart rate variability (HRV), skin conductance, blood pressure response to pain or sympathetic pupillomotor function between patients and controls. FMF patients revealed impaired parasympathetic pupillomotor function that was not associated with clinical parameters. However, patients that were on IL-1-blocking therapy had better parasympathetic pupillary function than patients on conventional treatment. CONCLUSIONS: FMF patients have AD in terms of symptoms and parasympathetic pupillomotor function. Dynamic pupillometry can provide additional information on autonomic regulation in patients with FMF.


Asunto(s)
Enfermedades del Sistema Nervioso Autónomo , Fiebre Mediterránea Familiar , Sistema Nervioso Autónomo , Enfermedades del Sistema Nervioso Autónomo/diagnóstico , Enfermedades del Sistema Nervioso Autónomo/etiología , Estudios de Casos y Controles , Estudios Transversales , Fiebre Mediterránea Familiar/complicaciones , Fiebre Mediterránea Familiar/diagnóstico , Frecuencia Cardíaca , Humanos
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