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1.
Radiat Prot Dosimetry ; 199(15-16): 1824-1828, 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37819323

RESUMO

Currently, the most used methods of plastic scintillator (PS) manufacturing are cell casting and bulk polymerisation, extrusion, injection molding, whereas digital light processing (DLP) 3D printing technique has been recently introduced. For our research, we measured blue-emitting EJ-200, EJ-208, green-emitting EJ-260, EJ-262 cell cast and two types of blue-emitting DLP-printed PSs. The light output of the samples, with the same dimension of 10 mm × 10 mm × 10 mm, was compared. The light output of the samples, relative to the reference EJ-200 cell-cast scintillator, equals about 40-49 and 70-73% for two types of 3D-printed, and two green-emitting cell-casted PSs, respectively. Performance of the investigated scintillators is sufficient to use them in a plastic scintillation dosemeter operating in high fluence gamma radiation fields.


Assuntos
Radiometria , Contagem de Cintilação , Contagem de Cintilação/métodos , Impressão Tridimensional
2.
Sci Rep ; 12(1): 18561, 2022 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-36329066

RESUMO

Raman spectroscopy and Raman imaging were used to identify the biochemical and structural features of human cancer lung cells (CCL-185) and the cancer cells supplemented with glucose and deuterated glucose at normal and hyperglycemia conditions. We found that isotope substitution of glucose by deuterated glucose allows to separate de novo lipid synthesis from exogenous uptake of lipids obtained from the diet. We demonstrated that glucose is largely utilized for de novo lipid synthesis. Our results provide a direct evidence that high level of glucose decreases the metabolism via oxidative phosphorylation in mitochondria in cancer cells and shifts the metabolism to glycolysis via Warburg effect. It suggests that hyperglycemia is a factor that may contribute to a more malignant phenotype of cancer cells by inhibition of oxidative phosphorylation and apoptosis.


Assuntos
Carcinoma , Hiperglicemia , Humanos , Análise Espectral Raman , Fosforilação Oxidativa , Glicólise/fisiologia , Glucose/metabolismo , Lipídeos , Pulmão/metabolismo
3.
Sci Rep ; 12(1): 2120, 2022 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-35136078

RESUMO

Cytochrome c (Cyt c) is a key protein that is needed to maintain life (respiration) and cell death (apoptosis). The dual-function of Cyt c comes from its capability to act as mitochondrial redox carrier that transfers electrons between the membrane-embedded complexes III and IV and to serve as a cytoplasmic apoptosis-triggering agent, activating the caspase cascade. However, the precise roles of Cyt c in mitochondria, cytoplasm and extracellular matrix under normal and pathological conditions are not completely understood. To date, no pathway of Cyt c release that results in caspase activation has been compellingly demonstrated in any invertebrate. The significance of mitochondrial dysfunctionality has not been studied in ductal carcinoma to the best of our knowledge. We used Raman spectroscopy and imaging to monitor changes in the redox state of the mitochondrial cytochromes in ex vivo surgically resected specimens of human breast tissues, and in vitro human breast cells of normal cells (MCF 10A), slightly malignant cells (MCF7) and highly aggressive cells (MDA-MB-231). We showed that Raman imaging provides insight into the biology of human breast ductal cancer. Here we show that proper concentration of monounsaturated fatty acids, saturated fatty acids, cardiolipin and Cyt c is critical in the correct breast ductal functioning and constitutes an important parameter to assess breast epithelial cells integrity and homeostasis. We look inside human breast ducts by Raman imaging answering fundamental questions about location and distribution of various biochemical components inside the lumen, epithelial cells of the duct and the extracellular matrix around the cancer duct during cancer development in situ. Our results show that human breast cancers demonstrate a redox imbalance compared to normal tissue. The reduced cytochrome c is upregulated in all stages of cancers development. The results of the paper shed light on a largely non-investigated issues regarding cytochromes and mitochondrial function in electron transfer chain. We found in histopathologically controlled breast cancer duct that Cyt c, cardiolipin, and palmitic acid are the main components inside the lumen of cancerous duct in situ. The presented results show direct evidence that Cyt c is released to the lumen from the epithelial cells in cancerous duct. In contrast the lumen in normal duct is empty and free of Cyt c. Our results demonstrate how Cyt c is likely to function in cancer development. We anticipate our results to be a starting point for more sophisticated in vitro and in vivo animal models. For example, the correlation between concentration of Cyt c and cancer grade could be tested in various types of cancer. Furthermore, Cyt c is a target of anti-cancer drug development and a well-defined and quantitative Raman based assay for oxidative phosphorylation and apoptosis will be relevant for such developments.


Assuntos
Neoplasias da Mama/metabolismo , Carcinoma Ductal de Mama/metabolismo , Citocromos c/metabolismo , Mitocôndrias/metabolismo , Análise Espectral Raman , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/etiologia , Carcinoma Ductal de Mama/diagnóstico por imagem , Carcinoma Ductal de Mama/etiologia , Feminino , Humanos , Técnicas In Vitro , Células MCF-7 , Oxirredução
4.
Spectrochim Acta A Mol Biomol Spectrosc ; 268: 120667, 2022 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-34865975

RESUMO

Raman spectroscopy and Raman imaging are powerful techniques to monitor biochemical composition around blood vessel. The aim of this study was to understand the role of pro- and antiangiogenic factors in angiogenesis process. Raman imaging and Raman single spectrum measurements allow the diagnosis of cancer biochemical changes in blood vessel based on several biomarkers simultaneously. We have demonstrated that Raman imaging combined with statistical methods are useful to monitoring pro- and antiangiogenic factors responsible for angiogenesis process. In this work Raman markers of proangiogenic and antiangiogenic factors were identified based on their vibrational signatures. Obtained results can help understand how growing tumor create its vascular system.


Assuntos
Neoplasias , Análise Espectral Raman , Inibidores da Angiogênese/farmacologia , Diagnóstico por Imagem , Humanos , Neoplasias/tratamento farmacológico , Vibração
5.
Spectrochim Acta A Mol Biomol Spectrosc ; 262: 120091, 2021 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-34175760

RESUMO

Spectroscopic methods provide information on the spatial localization of biochemical components based on the analysis of vibrational spectra. Raman spectroscopy and Raman imaging can be used to analyze various types of human brain tumors and breast cancers. The objective of this study is to evaluate the Raman biomarkers to distinguish tumor types by Raman spectroscopy and Raman imaging. We have demonstrated that bands characteristic for carotenoids (1156 cm-1, 1520 cm-1), proteins (1004 cm-1), fatty acids (1444 cm-1, 1655 cm-1) and cytochrome (1585 cm-1) can be used as universal biomarkers to assess aggressiveness of human brain tumors. The sensitivity and specificity obtained from PLS-DA have been over 73%. Only for gliosarcoma WHO IV the specificity is lower and takes equal 50%. The presented results confirm clinical potential of Raman spectroscopy in oncological diagnostics.


Assuntos
Neoplasias Encefálicas , Neoplasias da Mama , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias da Mama/diagnóstico por imagem , Diagnóstico por Imagem , Feminino , Humanos , Análise Espectral Raman , Vibração
6.
Sci Rep ; 9(1): 166, 2019 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-30655566

RESUMO

We have shown that Raman microspectroscopy is a powerful method for visualization of glycocalyx offering cellular interrogation without staining, unprecedented spatial and spectral resolution, and biochemical information. We showed for the first time that Raman imaging can be used to distinguish successfully between glycosylated and nonglycosylated proteins in normal and cancer tissue. Thousands of protein, lipid and glycan species exist in cells and tissues and their metabolism is monitored via numerous pathways, networks and methods. The metabolism can change in response to cellular environment alterations, such as development of a disease. Measuring such alterations and understanding the pathways involved are crucial to fully understand cellular metabolism in cancer development. In this paper Raman markers of glycogen, glycosaminoglycan, chondroitin sulfate, heparan sulfate proteoglycan were identified based on their vibrational signatures. High spatial resolution of Raman imaging combined with chemometrics allows separation of individual species from many chemical components present in each cell. We have found that metabolism of proteins, lipids and glycans is markedly deregulated in breast (adenocarcinoma) and brain (medulloblastoma) tumors. We have identified two glycoforms in the normal breast tissue and the malignant brain tissue in contrast to the breast cancer tissue where only one glycoform has been identified.


Assuntos
Adenocarcinoma/metabolismo , Encéfalo/metabolismo , Neoplasias da Mama/metabolismo , Mama/metabolismo , Neoplasias Cerebelares/metabolismo , Meduloblastoma/metabolismo , Encéfalo/patologia , Mama/patologia , Feminino , Humanos , Metabolismo dos Lipídeos , Polissacarídeos/metabolismo , Proteínas/metabolismo , Análise Espectral Raman/métodos
7.
J Environ Manage ; 222: 1-2, 2018 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-29800858

RESUMO

The discussion letter we received was carefully reviewed by us, authors. We would like to thank Moussavi et al. for their interest and emphasis on the originality of our studies. Every substantive discussion on study results is valuable, especially when it gives a new perspective on the results obtained. We would like to note that our manuscript lacks some of the results listed by Moussavi et al., not because of our ignorance, but because of the concept of our manuscript's structure. We would like to point out that the research methods used in the published manuscript were selected based on available literature. We also want to emphasise the very diversified scientific approach to procedures for determining the availability of trace elements in soil. This approach was also noted and clearly justified in many studies. We believe that the diversity of scientists' approach to the investigated subject is a very important and creative component of science.


Assuntos
Compostagem , Metais Pesados , Poluentes do Solo , Carvão Vegetal , Esgotos , Solo , Zea mays
8.
J Environ Manage ; 210: 87-95, 2018 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-29331853

RESUMO

Studies on the availability of heavy metals in composted organic materials and in soil amended with these materials are of practical significance. They are used in the assessment of the purity of the soil environment and of the biological value of plants intended for human and animal consumption. Composting of organic materials has a significant effect on changes in mobile forms of heavy metals. Therefore, the aim of this study was to determine the effect of the addition of biochar and sewage sludge on (i) the contents of water soluble forms of Cu, Cd, Pb, and Zn in composts; and (ii) the contents of mobile forms of these elements in sandy soil after the addition of composts. Addition of sewage sludge and biochar to maize straw did not increase the heavy metal forms extracted with water in total content of heavy metals. The content of Cd and Cu extracted with water in composts produced from maize straw and sewage sludge, and produced from maize straw, sewage sludge and biochar was higher than the one determined in compost produced from maize straw. The content of Pb and Zn extracted with water in compost produced from maize straw, sewage sludge and biochar was lower than in compost produced from maize straw. The addition of sewage sludge and biochar to maize straw had an immobilizing effect on mobile forms of the studied elements compared to compost produced from maize straw and sewage sludge. The addition of composts to soil decreased the contents of mobile forms of Cu, Cd, and Pb extracted with 1 M NH4NO3 compared to the contents in the control soil. However, the content of Zn extracted with NH4NO3 increased in treatments with 0.5% dose of compost produced from maize straw and sewage sludge and 0.5% dose of compost produced from maize straw, sewage sludge and biochar. In none of the analyzed cases, the application of the composts produced did not exceed the acceptable content of studied elements in the soil.


Assuntos
Carvão Vegetal , Compostagem , Metais Pesados/química , Animais , Humanos , Esgotos , Solo , Poluentes do Solo , Zea mays
9.
Eur Phys J C Part Fields ; 77(7): 475, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28943795

RESUMO

The Compact Linear Collider (CLIC) is an option for a future [Formula: see text] collider operating at centre-of-mass energies up to [Formula: see text], providing sensitivity to a wide range of new physics phenomena and precision physics measurements at the energy frontier. This paper is the first comprehensive presentation of the Higgs physics reach of CLIC operating at three energy stages: [Formula: see text], 1.4 and [Formula: see text]. The initial stage of operation allows the study of Higgs boson production in Higgsstrahlung ([Formula: see text]) and [Formula: see text]-fusion ([Formula: see text]), resulting in precise measurements of the production cross sections, the Higgs total decay width [Formula: see text], and model-independent determinations of the Higgs couplings. Operation at [Formula: see text] provides high-statistics samples of Higgs bosons produced through [Formula: see text]-fusion, enabling tight constraints on the Higgs boson couplings. Studies of the rarer processes [Formula: see text] and [Formula: see text] allow measurements of the top Yukawa coupling and the Higgs boson self-coupling. This paper presents detailed studies of the precision achievable with Higgs measurements at CLIC and describes the interpretation of these measurements in a global fit.

10.
Spectrochim Acta A Mol Biomol Spectrosc ; 169: 182-91, 2016 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-27376758

RESUMO

Raman microspectroscopy combined with fluorescence were used to study the distribution of Hematoporphyrin (Hp) in noncancerous and cancerous breast tissues. The results demonstrate the ability of Raman spectroscopy to distinguish between noncancerous and cancerous human breast tissue and to identify differences in the distribution and photodegradation of Hematoporphyrin, which is a photosensitizer in photodynamic therapy (PDT), photodynamic diagnosis (PDD) and photoimmunotherapy (PIT) of cancer. Presented results show that Hematoporphyrin level in the noncancerous breast tissue is lower compared to the cancerous one. We have proved also that the Raman intensity of lipids and proteins doesn't change dramatically after laser light irradiation, which indicates that the PDT treatment destroys preferably cancer cells, in which the photosensitizer is accumulated. The specific subcellular localization of photosensitizer for breast tissues samples soaked with Hematoporphyrin was not observed.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Mama/diagnóstico por imagem , Hematoporfirinas/análise , Imagem Óptica/métodos , Fármacos Fotossensibilizantes/análise , Análise Espectral Raman/métodos , Feminino , Humanos , Espectrometria de Fluorescência/métodos
11.
Folia Morphol (Warsz) ; 72(4): 293-9, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24402749

RESUMO

The aim of the study was to investigate the distribution of the circle of Willis variants in Polish population by means of computed tomography angiography (CTA). The results were then analysed and compared with another study that used similar methods but that was carried out on an ethnically distinct population. Patients presenting with intracranial pathology were excluded from the initial study population. In total, 250 CTA belonging to 129 female and 121 male patients were reviewed. A modified classification system of the circle was proposed, which took into consideration the anterior and the posterior aspects of the circle individually. The typical variant of Willis's circle occurred in 16.80% of cases. The anterior and the posterior portions of the circle were normal in 47.20% and 26.80% of the patients respectively. As for the anterior part, lack of the anterior communicating artery was the most frequent abnormality (22.80%). Bilateral absence of posterior communicating arteries was the most common anomaly in the posterior part of the circle (29.20%). This type of anomaly was also the most common, when taking into consideration the entire circle (12.00%). There were statistically significant differences between the age groups and genders when considering the occurrence of an incomplete circle. Overall, a substantial proportion of patients manifested clinically important variants that were incapable of providing collateral circulation. Comparison with other imaging-based and cadaveric studies revealed noticeable differences, that may have resulted from the variable technical features of other studies or other factors such as the ethnical origins of the studied populations.


Assuntos
Angiografia Cerebral , Círculo Arterial do Cérebro/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Cadáver , Círculo Arterial do Cérebro/anormalidades , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Polônia , Adulto Jovem
13.
Open Orthop J ; 2: 33-9, 2008 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-19587797

RESUMO

Pelvic ring fractures that occur as a result of substantial orthopedic trauma are frequently repaired using iliosacral screws to stabilize the fracture. Stimulus evoked electromyography, using pulsed current stimuli provided through the drill bit cathode, has been advocated to prevent nerve root injury during iliosacral screw insertion. Our objective was to examine the effects of anode location, drill bit position, and anatomical structure on the nerve monitoring technique. A three-dimensional finite element model was constructed from computed tomography data to evaluate the effectiveness of five anode locations at four stations of drill bit insertion. Results indicate that the anode location should be at the midline or on the side contralateral to drill bit insertion. Locating the anode at other positions, such that the nerve root is outside of the primary electromagnetic field, leads to an attenuated electromyographic response that will ultimately lead to the failure of the monitoring technique.

14.
Phys Med Biol ; 52(16): 4953-66, 2007 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-17671346

RESUMO

Nanodosimetric single-event distributions or their mean values may contribute to a better understanding of how radiation induced biological damages are produced. They may also provide means for radiation quality characterization in therapy beams. Experimental nanodosimetry is however technically challenging and Monte Carlo simulations are valuable as a complementary tool for such investigations. The dose-mean lineal energy was determined in a therapeutic p(65)+Be neutron beam and in a (60)Co gamma beam using low-pressure gas detectors and the variance-covariance method. The neutron beam was simulated using the condensed history Monte Carlo codes MCNPX and SHIELD-HIT. The dose-mean lineal energy was calculated using the simulated dose and fluence spectra together with published data from track-structure simulations. A comparison between simulated and measured results revealed some systematic differences and different dependencies on the simulated object size. The results show that both experimental and theoretical approaches are needed for an accurate dosimetry in the nanometer region. In line with previously reported results, the dose-mean lineal energy determined at 10 nm was shown to be related to clinical RBE values in the neutron beam and in a simulated 175 MeV proton beam as well.


Assuntos
Modelos Biológicos , Método de Monte Carlo , Nanotecnologia/métodos , Terapia por Captura de Nêutron/métodos , Radiometria/métodos , Simulação por Computador , Modelos Estatísticos , Dosagem Radioterapêutica , Análise de Regressão , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
15.
Radiat Prot Dosimetry ; 126(1-4): 652-6, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17504751

RESUMO

Secondary neutrons produced in high-energy therapeutic ion beams require special attention since they contribute to the dose delivered to patient, both to tumour and to the healthy tissues. Moreover, monitoring of neutron production in the beam line elements and the patient is of importance for radiation protection aspects around ion therapy facility. Monte Carlo simulations of light ion transport in the tissue-like media (water, A-150, PMMA) and materials of interest for shielding devices (graphite, steel and Pb) were performed using the SHIELD-HIT and MCNPX codes. The capability of the codes to reproduce the experimental data on neutron spectra differential both in energy and angle is demonstrated for neutron yield from the thick targets. Both codes show satisfactory agreement with the experimental data. The absorbed dose due to neutrons produced in the water and A-150 phantoms is calculated for proton (200 MeV) and carbon (390 MeV/u) beams. Secondary neutron dose contribution is approximately 0.6% of the total dose delivered to the phantoms by proton beam and at the similar level for both materials. For carbon beam the neutron dose contribution is approximately 1.0 and 1.2% for the water and A-150 phantoms, respectively. The neutron ambient dose equivalent, H(10), was determined for neutrons leaving different shielding materials after irradiation with ions of various energies.


Assuntos
Radioterapia com Íons Pesados , Modelos Biológicos , Nêutrons , Monitoramento de Radiação/instrumentação , Proteção Radiológica/instrumentação , Eficiência Biológica Relativa , Simulação por Computador , Desenho de Equipamento , Análise de Falha de Equipamento , Humanos , Teste de Materiais , Doses de Radiação , Proteção Radiológica/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
16.
Radiat Prot Dosimetry ; 115(1-4): 58-62, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16381682

RESUMO

A Monte Carlo study of the Feynman-method with a simple code simulating the multiplication chain, confined to pertinent time-dependent phenomena has been done. The significance of its key parameters (detector efficiency and dead time, k-source and spallation neutrons multiplicities, required number of fissions etc.) has been discussed. It has been demonstrated that this method can be insensitive to properties of the zones surrounding the core, whereas is strongly affected by the detector dead time. In turn, the influence of harmonics in the neutron field and of the dispersion of spallation neutrons has proven much less pronounced.


Assuntos
Desenho Assistido por Computador , Modelos Teóricos , Nêutrons , Aceleradores de Partículas/instrumentação , Proteção Radiológica/instrumentação , Radiometria/métodos , Eliminação de Resíduos/instrumentação , Algoritmos , Partículas alfa , Simulação por Computador , Desenho de Equipamento , Análise de Falha de Equipamento , Resíduos Industriais/prevenção & controle , Doses de Radiação , Proteção Radiológica/métodos , Eliminação de Resíduos/métodos
20.
Br J Haematol ; 96(3): 514-20, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9054658

RESUMO

We have previously reported that glycophorin A (GPA) of human erythrocytes (carrying blood group M and N determinants) was totally digested by incubation of erythrocytes with human neutrophil elastase (HNE) and cathepsin G (CathG). The membrane-bound GPA fragments fractionated by SDS-PAGE gave characteristic patterns of bands detected by immunoblotting with the monoclonal antibody PEP80. Erythrocytes were incubated with HNE and CathG at low enzyme concentrations, similar to those found in vivo. Characteristic electrophoretic patterns of bands derived from a partial GPA digestion were observed and these patterns were different for both enzymes and different from those obtained after total GPA digestion. GPA was also partially digested by incubation of erythrocytes with granulocytes in the presence of Ca2+ and calcium ionophore and electrophoretic pattern of digestion products was similar to that obtained with low doses of HNE. No GPA digestion products were detected after treatment of erythrocytes with plasmin and kallikrein. Untreated erythrocytes of 21 patients with various myelo- or lymphoproliferative disorders were tested by SDS-PAGE of RBC membranes and immunoblotting with the anti-GPA PEP80 antibody. GPA degradation products, resembling those formed by a mild CathG treatment of control RBC, were detected in nine patients. GPA fragmentation was in some cases accompanied by a reduced expression of blood group MN determinants. No distinct relation was observed between the occurrence of GPA degradation in erythrocytes and increases in plasma concentrations of HNE-alpha1-proteinase inhibitor (alpha1-PI) complex considered to be an indication of a release of neutrophil proteinases in vivo. However, the results suggested that a partial GPA degradation in haematological proliferative disorders may occur due to limited proteolysis by neutrophil proteinases, most likely by CathG.


Assuntos
Catepsinas/metabolismo , Eritrócitos/enzimologia , Glicoforinas/metabolismo , Elastase de Leucócito/metabolismo , Transtornos Linfoproliferativos/enzimologia , Transtornos Mieloproliferativos/enzimologia , Neutrófilos/enzimologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Catepsina G , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Serina Endopeptidases
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