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Frontiers in Chemistry 2019Trace elements play a crucial role in many biochemical processes, mainly as components of vitamins and enzymes. Although small amounts of metal ions have protective... (Review)
Review
Trace elements play a crucial role in many biochemical processes, mainly as components of vitamins and enzymes. Although small amounts of metal ions have protective properties, excess metal levels result in oxidative injury, which is why metal ion homeostasis is crucial for the proper functioning of the brain. The changes of their level in the brain have been proven to be a risk factor for Alzheimer's, Parkinson's, and Huntington's diseases, as well as amyotrophic lateral sclerosis. Therefore, it is currently an important application of various analytical methods. This review covers the most important of them: inductively coupled ground mass spectrometry (ICP-MS), flame-induced atomic absorption spectrometry (FAAS), electrothermal atomic absorption spectrometry (GFAAS), optical emission spectrometry with excitation in inductively coupled plasma (ICP-OES), X-ray fluorescence spectrometry (XRF), and neutron activation analysis (NAA). Additionally, we present a summary of concentration values found by different research groups.
PubMed: 30891444
DOI: 10.3389/fchem.2019.00115 -
Applied Radiation and Isotopes :... Dec 2018A Proton Accelerator based Boron Neutron Capture Therapy (A-BNCT) facility is under development in Korea. Neutron beams for treatment are produced from a beryllium (Be)...
A Proton Accelerator based Boron Neutron Capture Therapy (A-BNCT) facility is under development in Korea. Neutron beams for treatment are produced from a beryllium (Be) target and an 8 mA, 10 MeV proton beam. The purpose of the research is a radiation shielding analysis and an activation analysis for the facility design satisfying the radiation safety requirements as well as obtaining an operating license for the radiation facility according to a domestic nuclear commissioning procedure. The radiation shielding analysis was performed using the MCNPX computational particle transport code. The radiation source terms in the facility were evaluated and utilized in the shielding calculations. The minimum concrete thickness satisfying the designated dose rate of 5 μSv/h for the worker's area and 0.25 μSv/h for the public area were estimated and applied to the design. For an assessment of the radiation safety inside the facility, the dose rates were evaluated at several positions, such as behind the shielding door, around the primary barriers near the radiation sources, and in the penetrations of the ducts. The dose rate distribution was mapped for verification of the radiation safety for the entire facility. An activation analysis was carried out for the concrete walls, air, target assembly, beryllium target, and cooling water using FISPACT-2010 code. Concentrations of the activation products and dose rate induced by the radionuclides after shutdown were evaluated for the purpose of safe operation of the facility. The results were reviewed with the radiation safety regulations in Korea. As a result, it was proved that the final facility design satisfies the safety requirements.
Topics: Boron Neutron Capture Therapy; Equipment Safety; Facility Design and Construction; Humans; Licensure; Occupational Exposure; Particle Accelerators; Protons; Radiation Exposure; Radiation Protection; Republic of Korea
PubMed: 30273764
DOI: 10.1016/j.apradiso.2018.09.022 -
Cytometry. Part B, Clinical Cytometry Jul 2018Conventional data analysis of flow cytometry-based basophil activation testing requires repetitive, labor-intensive analysis that hampers efforts to standardize testing...
BACKGROUND
Conventional data analysis of flow cytometry-based basophil activation testing requires repetitive, labor-intensive analysis that hampers efforts to standardize testing for clinical applications. Using an open-source platform, we developed and implemented a programmatic approach to the analysis of the basophil activation test (BAT) by flow cytometry.
METHODS
Using the BÜHLMANN FlowCAST® assay, peripheral blood from peanut allergic patients undergoing oral immunotherapy was incubated with peanut allergens (Arah1, Arah2, Arah6, whole peanut extract) and stained with fluorescent antibodies to CCR3 and CD63 for the development of a data-driven programmatic analysis using Bioconductor and R. Basophil identification using clustering and classification was validated using manually gated comparisons in an experimental subset. Reproducibility of CD63 upregulation set on unstimulated or anti-FcERI stimulated basophils was compared.
RESULTS
BAT analysis of 294 experiments was successful in 91.5% using the above approach, with a total of 7,166 individual basophil activation tests from 269 experiments. We estimate this represents a net saving of 1340 min of labor by a skilled operator. Medium-based gating correlated to respective manual gating more closely than anti-FcERI based gating (R = 0.96 vs. R = 0.84, P < 0.001). Only 2% of the basophil activation results were significantly different from manual gating. Quality measures of the experiments and other measures of basophil activation were also provided by the analysis.
CONCLUSIONS
We present a novel data-driven flow cytometric platform for the analysis of clinical basophil activation testing, providing a high throughput objective approach to basophil activation analysis. © 2017 International Clinical Cytometry Society.
Topics: Algorithms; Basophil Degranulation Test; Child; Flow Cytometry; Humans; Male; Peanut Hypersensitivity
PubMed: 28618453
DOI: 10.1002/cyto.b.21537 -
Forensic Science International. Synergy 2019The commerce of illegal and counterfeit medicinal products on internet is a serious criminal problem. Drugs for erectile dysfunction such as phosphodiesterase type 5...
Instrumental neutron activation analysis (INAA) and liquid chromatography (LC) coupled to high resolution mass spectrometry (HRMS) characterisation of sildenafil based products seized on the Italian illegal market.
The commerce of illegal and counterfeit medicinal products on internet is a serious criminal problem. Drugs for erectile dysfunction such as phosphodiesterase type 5 inhibitor are the most commonly counterfeited medicines in Europe. The search of possible toxic chemical substances in seized products is needed. Moreover, the profiling of the material can be the source of relevant forensic information. For the first time a combined approach based on liquid chromatography (LC) coupled to high resolution mass spectrometry (HRMS) and instrumental neutron activation analysis (INAA) is proposed and tested, allowing characterisation of both authentic and illegal pharmaceuticals containing sildenafil seized in Italy. LC-HRMS allowed the detection and identification of unknown impurities not reported on labels in illegal products and the quantitation of the sildenafil. INAA showed to be suitable to provide both qualitative and quantitative information for forensic purposes on 23 elements, allowing discrimination between legal and illegal products.
PubMed: 32411964
DOI: 10.1016/j.fsisyn.2019.07.004 -
JACC. Clinical Electrophysiology Aug 2022The interatrial septum (IAS) is thought to be involved in the mechanism of persistent atrial fibrillation (PeAF). Simultaneous contact mapping of both sides of the IAS...
BACKGROUND
The interatrial septum (IAS) is thought to be involved in the mechanism of persistent atrial fibrillation (PeAF). Simultaneous contact mapping of both sides of the IAS has not been performed previously.
OBJECTIVES
The purpose of this study was to describe wave front (WF) activation patterns and extent of left and right atrial septal electrical dissociation in patients with PeAF.
METHODS
Simultaneous mapping of both atrial septal surfaces using 2 high-density grid catheters was performed. Filtered electrograms of continuous atrial fibrillation, sinus rhythm (SR), and atrial pacing recordings were exported to MATLAB for off-line phase/activation analysis, and activation patterns on paired surfaces were analyzed. WF activation patterns between the 2 grids were evaluated to determine whether activation WFs were associated or dissociated.
RESULTS
Eight patients with PeAF undergoing catheter ablation were included. Complete dissociation of WF activation patterns between the 2 sides of the septum existed throughout the mapping period with no 2 consecutive WF activation patterns matching. Single linear WFs were the most prevalent activation pattern on both septal grids. No focal breakthroughs were seen. Transient rotational activity was seen in 10% of phase activations. During SR and atrial pacing, both grids appeared to be activated independent of each other with no evidence of contralateral conduction across the 2 grids.
CONCLUSIONS
Simultaneous biatrial septal mapping of human PeAF, SR, and atrial pacing shows complete WF dissociation between the left and right IAS with no evidence of trans-septal conduction, indicating that the 2 sides function as electrically discrete structures. No stable septal drivers were observed. These findings may have implications for mapping and ablation of PeAF.
Topics: Atrial Appendage; Atrial Fibrillation; Catheter Ablation; Heart Atria; Heart Septal Defects, Atrial; Humans
PubMed: 35981802
DOI: 10.1016/j.jacep.2022.04.014 -
Experimental Astronomy 2023POLAR-2, a plastic scintillator based Compton polarimeter, is currently under development and planned for a launch to the China Space Station in 2025. It is intended to...
POLAR-2, a plastic scintillator based Compton polarimeter, is currently under development and planned for a launch to the China Space Station in 2025. It is intended to shed a new light on our understanding of Gamma-Ray Bursts by performing high precision polarization measurements of their prompt emission. The instrument will be orbiting at an average altitude of 383 km with an inclination of 42° and will be subject to background radiation from cosmic rays and solar events. In this work, we tested the performance of plastic scintillation bars, EJ-200 and EJ-248M from Eljen Technology, under space-like conditions, that were chosen as possible candidates for POLAR-2. Both scintillator types were irradiated with 58 MeV protons at several doses from 1.89 Gy(corresponding to about 13 years in space for POLAR-2) up to 18.7 Gy, that goes far beyond the expected POLAR-2 life time. Their respective properties, expressed in terms of light yield, emission and absorption spectra, and activation analysis due to proton irradiation are discussed. Scintillators activation analyses showed a dominant contribution of β + decay with a typical for this process gamma-ray energy line of 511 keV.
PubMed: 38145002
DOI: 10.1007/s10686-023-09906-8 -
Applied Radiation and Isotopes :... Sep 2022This work presents neutron flux calculation results and specific decay heat and activity for the European DEMO reactor divertor structure. Two DEMO 2017 models were used...
This work presents neutron flux calculation results and specific decay heat and activity for the European DEMO reactor divertor structure. Two DEMO 2017 models were used in calculations; one with a homogenised WCLL breeder blanket and the other with a homogenised HCPB breeder blanket. The neutron flux calculations were performed using MCNP6 code with JEFF 3.2 nuclear data. Activation and decay heat calculations were performed using the FISPACT-II code with TENDL - 2017 nuclear data library.
Topics: Activation Analysis; Hot Temperature; Neutrons; Radioisotopes
PubMed: 35714517
DOI: 10.1016/j.apradiso.2022.110314 -
Neurophotonics Jan 2021Functional near-infrared spectroscopy (fNIRS) has been widely used to probe human brain function during task state and resting state. However, the existing analysis...
Functional near-infrared spectroscopy (fNIRS) has been widely used to probe human brain function during task state and resting state. However, the existing analysis toolboxes mainly focus on task activation analysis, few software packages can assist resting-state fNIRS studies. We aimed to provide a versatile and easy-to-use toolbox to perform analysis for both resting state and task fNIRS. We developed a MATLAB toolbox called NIRS-KIT that works for both resting-state analysis and task activation detection. NIRS-KIT implements common and necessary processing steps for performing fNIRS data analysis, including data preparation, quality control, preprocessing, individual-level analysis, group-level statistics with several popular statistical models, and multiple comparison correction methods, and finally results visualization. For resting-state fNIRS analysis, functional connectivity analysis, graph theory-based network analysis, and amplitude of low-frequency fluctuations analysis are provided. Additionally, NIRS-KIT also supports activation analysis for task fNIRS. NIRS-KIT offers an open source tool for researchers to analyze resting-state and/or task fNIRS data in one suite. It contains several key features: (1) good compatibility, supporting multiple fNIRS recording systems, data formats of NIRS-SPM and Homer2, and the shared near-infrared spectroscopy format data format recommended by the fNIRS society; (2) flexibility, supporting customized preprocessing scripts; (3) ease-to-use, allowing processing fNIRS signals in batch manner with user-friendly graphical user interfaces; and (4) feature-packed data viewing and result visualization. We anticipate that this NIRS-KIT will facilitate the development of the fNIRS field.
PubMed: 33506071
DOI: 10.1117/1.NPh.8.1.010802 -
Journal of Radioanalytical and Nuclear... Oct 2017A new γγ coincidence system has been set up at NIST. It is operated with a digital data finder supported by new software developed at NIST. The system is used to...
A new γγ coincidence system has been set up at NIST. It is operated with a digital data finder supported by new software developed at NIST. The system is used to explore possible enhancements in instrumental neutron activation analysis (INAA) and study applicability to neutron capture prompt gamma activation analysis (PGAA). The performance of the system is tested with certified reference materials for efficiency calibration and quantitative performance. Comparisons of INAA results based on conventional gamma-ray spectrometry data with INAA results based on coincidence data obtained from the same samples show improvements in the counting uncertainties and demonstrates the quantitative accuracy of the new system.
PubMed: 29056809
DOI: 10.1007/s10967-017-5342-7 -
Environmental Monitoring and Assessment Dec 2023Active biomonitoring using the moss bag technique was applied to examine the atmospheric deposition of potentially toxic and other elements in recreational areas of...
Active biomonitoring using the moss bag technique was applied to examine the atmospheric deposition of potentially toxic and other elements in recreational areas of Moscow. Moss bags with Sphagnum girgensohnii were placed in the territory of seven parks (Losiny Ostrov, Victory Park, Ostankino, Sokolniki, Izmailovo, Kuzminki-Lyublino, Tsaritsyno) at three locations in each park from June to September 2018. The content of 32 chemical elements: Na, Mg, Al, Cl, K, Ca, Sc, V, Mn, Fe, Co, Zn, As, Br, Rb, Sr, Mo, Sb, Cs, Ba, La, Sm, Tb, Hf, Ta, W, Au, Th, U, Cu, Pb, and Cd in moss samples was determined by instrumental neutron activation analysis and atomic absorption spectrometry. After a 3-month exposure period, high uptake of Sb, U, Th, Sm, La, Mo, Zn, Co, Fe, V, Sc, etc. was observed in some of the moss samples. The physiologically active elements Cl and K and alkaline elements Rb and Cs were depleted from the moss tissue during the exposure. The high accumulation of Zn, Pb, Cu, Co, V, and Sb in moss samples evidenced an anthropogenic impact on the parks, mainly associated with road traffic. To determine the level of pollution, a set of environmental indices was calculated: contamination factor (CF), enrichment factor (EF), total pollution index (TPI), and relative accumulation factor (RAF). The highest RAF values were obtained for Sb on the territory of all parks. According to EF, the samples were enriched in Al, Fe, U, Pb, Cd, Au, Sb, Th, and Ta. High CF values were obtained for sites in Losiny Ostrov, Izmailovo, Tsaritsyno, and Kuzminki-Lyublino located close to roads. According to TPI, the level of air pollution on the territory of the abovementioned parks varied from moderate to high. To identify the major sources of pollution, correlation analysis and principal component analysis were applied.
Topics: Biological Monitoring; Air Pollutants; Moscow; Environmental Monitoring; Cadmium; Lead; Bryophyta; Trace Elements
PubMed: 38146013
DOI: 10.1007/s10661-023-12210-9