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Background and Objectives: This study aimed to observe the relationship between trace element concentrations in lung tissue from lung non-small cell lung carcinoma (NSCLC) patients and prognosis. Materials and Methods: The concentrations of various trace elements in the lung tissues were measured by a particle-induced X-ray emission (PIXE) system, and the results were analyzed for statistical significance. Eight essential trace elements, Cr, Mn, Fe, Co, Cu, Zn, Se, and Mo, were analyzed. We investigated the relationship between trace element concentrations and disease-free survival (DFS) and overall survival (OS) in NSCLC patients. Results: A total of 129 NSCLC patients and 20 control patients were included in this study. As for DFS, Co was the only element that showed a significant difference, and the high Co group had better DFS (HR: 0.352, 95% CI = 0.128-0.97). No significant difference was observed for Cr, Mn, Fe, Se, or Mo, but DFS tended to be better in the high trace element group. No significant difference was observed for Cu and Zn, but DFS tended to be good in the low trace element group. As for OS, Cr was the only element that showed a significant difference, and the high Cr element group had better OS (HR: 0.477, 95% CI = 0.128-0.97). Conclusions: This study suggests that the prognosis is good in lung cancer cases with high intratumoral concentrations of Co and Cr. The dynamics of trace elements in body and in tumor tissue have not been well established, and we consider that more research is necessary in the future.
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Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Oligoelementos , Cromo , Humanos , PrognósticoRESUMO
It is of great importance to study the alignment of atoms in collision process in elementary analysis with a Particle Induced X-ray Emission (PIXE) technique. The measurement of alignment can also offer an effective testing ground for developing theory models in ionization process. The typical L X-ray spectra are measured for Ag thin target by 15âkeV electron impact at emission angles from 0° to 25°. Angular dependence of intensity ratios Lα/Lß1, Lß2/Lß1 and Lγ/Lß1 are investigated as a function of the second-order Legendre polynomial P2(cosθ). This study found that Lß2 line exhibits anisotropic emission spatially, while the emission of Lα, Lß1 and Lγ1 lines is isotropic. The results are interpreted by the influence of the Coster-Kronig (CK) transitions on the spatial distribution of X-ray emission. The anisotropy parameter ß for Lß2 lines is obtained experimentally and consequently the alignment degree A20 for L3 subshell is determined by taking CK transition into account. Namely, the alignment does exist in L3-subshell for atomic ionization by electron impact. The measurements offer an evidence to the existence of alignment for atomic ionization in electron-impact process.
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Elétrons , Prata/química , Espectrometria por Raios X/métodos , AnisotropiaRESUMO
Nanoparticle (NP)-based solutions for oncotherapy promise an improved efficiency of the anticancer response, as well as higher comfort for the patient. The current advancements in cancer treatment based on nanotechnology exploit the ability of these systems to pass biological barriers to target the tumor cell, as well as tumor cell organelles. In particular, iron oxide NPs are being clinically employed in oncological management due to this ability. When designing an efficient anti-cancer therapy based on NPs, it is important to know and to modulate the phenomena which take place during the interaction of the NPs with the tumor cells, as well as the normal tissues. In this regard, our review is focused on highlighting different approaches to studying the internalization patterns of iron oxide NPs in simple and complex 2D and 3D in vitro cell models, as well as in living tissues, in order to investigate the functionality of an NP-based treatment.
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We aimed to evaluate the types and concentrations of trace elements in tears of individuals living in urban and rural environments using particle induced X-ray emission (PIXE) and the possible association with exposure to air pollution and suggest a novel method for tear-based biomonitoring studies. This cross-sectional pilot study comprised 42 healthy subjects, 28 living in a rural area and 14 in an industrial city. Tears were collected with Schirmer paper and characterized by PIXE. Trace element concentrations from both eyes were averaged together with environmental pollution data. Main outcome measures were between-group differences in types and concentrations of trace elements in tears and comparison to environmental data. The rural group included 12/28 men, mean age 45.2 ± 14.8 years. The urban group consisted of 11/14 men of mean age 27 ± 5.9 years. Six rural and all urban were active smokers. Air pollution data showed more toxic elements in the rural environment. On PIXE analysis, chlorine, sodium, and potassium were found in similar concentrations in all samples. Normalizing to chlorine yielded higher values of aluminum, iron, copper, and titanium in the rural group; aluminum was found only in the rural group. The higher levels of certain trace elements in the rural group may, in part, be a consequence of exposure to specific environmental conditions. No direct association was found with air pollution data. PIXE is useful to analyze trace elements in tears, which might serve as a marker for individual exposure to environmental pollutants in biomonitoring studies.
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Brazilian coffee is well known worldwide due to its quality and richness in taste. The aim of the present study is to provide the elemental characterization of Brazilian coffee along different stages of the drip brewing process. To that end, samples from roasted ground coffee, spent coffee, paper filters and the final beverage were analyzed with one single ion beam technique, namely particle-induced X-ray emission (PIXE). In total, over 140 samples from 8 different Brazilian brands of ground coffee were analyzed. Large differences in some elemental concentrations were observed among different brands and among different batches of a single brand, which leads to high variances in the data. Concerning the beverage preparation, the analysis of the spent coffee shows that the transfer ratio from the ground coffee to the beverage differs for each element. Our results indicate that potassium and chlorine have the highest transfer ratio. Moreover, the concentration of rubidium is relatively high in drinking coffee. Finally, there is no influence of the elemental composition of paper filter in the preparation of drinking coffee.
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Café/anatomia & histologia , Tecnologia de Alimentos/métodos , Extratos Vegetais/química , Bebidas , Brasil , Filtração , Temperatura Alta , Espectrometria por Raios X , PaladarRESUMO
Development of non-destructive or micro-invasive scientific diagnostic techniques gained an outmost importance in the field of Cultural Heritage, contributing to assess authenticity, provenience and age of the objects, as well as supplying additional information to art conservators, to accomplish suitable restoring and preservative procedures. However, each diagnostic technique has its own advantages and limitations, thus in many cases the optimal sample characterization requires a synergy between different analytical approaches. In this context, Particle Induced X-ray Emission (PIXE) and high energy (HE) PIXE with 3â¯MeV and 17â¯MeV proton beams respectively, Elastic Backscattering Spectrometry (EBS) and micro X-Ray Fluorescence (µ-XRF) techniques were applied in a multi-analytical approach to characterize the composition of the artifacts. The analysed samples were four Roman Imperial coins belonging to different periods between 41 A.D. and 4 B.C. The employed Ion Beam Analysis (IBA) and XRF provided comparable quantitative results relative to the main sample elemental composition. The obtained results vary significantly from one coin to the other, depending on the production date and place, and on the conservation conditions.
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Proton-induced reaction (p,α) is one type of nuclear reaction analysis (NRA) suitable especially for light element quantification. In the case of lithium quantification presented in this work, accelerated protons with an energy about of 850 keV were used to induce the 7Li(p,α)4He reaction in standard reference and geological samples such as tourmaline and other Li-minerals. It is shown that this technique for lithium quantification allowed for measurement of concentrations down below one ppm. The possibility to relate the lithium content with the boron content in a single analysis was also demonstrated using tourmaline samples, both in absolute concentration and in lateral distribution. In addition, Particle induced X-ray emission (PIXE) was utilized as a complementary IBA technique for simultaneous mapping of elements heavier than sodium.