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1.
Nanotechnology ; 35(15)2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38194713

RESUMO

Synthesis of Mo2C bare MXenes, without surface terminations groups, via chemical vapor deposition (CVD) on metal foils is scientifically a very intriguing crystal growth process, and there are still challenges and limited fundamental understanding to overcome to obtain high yield and wide crystal size lateral growth. Achieving large area coverage via direct growth is scientifically vital to utilize the full potential of their unique properties in different applications. In this study, we sought to expand the boundaries of the current CVD growth approach for Mo2C MXenes and gain insights into the possibilities and limitations of large area growth, with a particular focus on controlling Mo concentration. We report a facile modification of their typical CVD growth protocol and show its influence on the Mo2C synthesis, with growth times spanning up to 3 h. Specifically, prior to initiating the CVD growth process, we introduced a holding step in temperature at 1095 °C. This proved to be beneficial in increasing the Mo concentration on the liquid Cu growth surface. We achieved an average Mo2C crystals coverage of approximately 50% of the growth substrate area, increased tendency of coalescence and merging of individual flakes, and lateral flake sizes up to 170µm wide. To gain deeper understanding into their CVD growth behavior, we conducted a systematic investigation of the effect of several factors, including (i) a holding step time on Mo diffusion rate through molten Cu, (ii) the Cu foil thickness over the Mo foil, and (iii) the CVD growth time. Phase, chemical and microstructural characterization by x-ray diffraction, x-ray photon spectroscopy, SEM and scanning/transmission electron microscopy revealed that the grown crystals are single phaseα-Mo2C. Furthermore, insights gained from this study sheds light on crucial factors and inherent limitations that are essential to consider and may help guide future research progress in CVD growth of bare MXenes.

2.
Cereb Cortex ; 31(7): 3426-3434, 2021 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-33676369

RESUMO

Younger age at first exposure (AFE) to repetitive head impacts while playing American football increases the risk for later-life neuropsychological symptoms and brain alterations. However, it is not known whether AFE is associated with cortical thickness in American football players. Sixty-three former professional National Football League players (55.5 ± 7.7 years) with cognitive, behavioral, and mood symptoms underwent neuroimaging and neuropsychological testing. First, the association between cortical thickness and AFE was tested. Second, the relationship between clusters of decreased cortical thickness and verbal and visual memory, and composite measures of mood/behavior and attention/psychomotor speed was assessed. AFE was positively correlated with cortical thickness in the right superior frontal cortex (cluster-wise P value [CWP] = 0.0006), the left parietal cortex (CWP = 0.0003), and the occipital cortices (right: CWP = 0.0023; left: CWP = 0.0008). A positive correlation was found between cortical thickness of the right superior frontal cortex and verbal memory (R = 0.333, P = 0.019), and the right occipital cortex and visual memory (R = 0.360, P = 0.012). In conclusion, our results suggest an association between younger AFE and decreased cortical thickness, which in turn is associated with worse neuropsychological performance. Furthermore, an association between younger AFE and signs of neurodegeneration later in life in symptomatic former American football players seems likely.


Assuntos
Atletas , Espessura Cortical do Cérebro , Lesões Encefálicas Traumáticas/diagnóstico por imagem , Córtex Cerebral/diagnóstico por imagem , Encefalopatia Traumática Crônica/diagnóstico por imagem , Futebol Americano , Adulto , Afeto/fisiologia , Fatores Etários , Idoso , Atenção/fisiologia , Lesões Encefálicas Traumáticas/fisiopatologia , Córtex Cerebral/patologia , Encefalopatia Traumática Crônica/fisiopatologia , Lobo Frontal/diagnóstico por imagem , Lobo Frontal/patologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Memória/fisiologia , Pessoa de Meia-Idade , Testes Neuropsicológicos , Lobo Occipital/diagnóstico por imagem , Lobo Occipital/patologia , Tamanho do Órgão , Lobo Parietal/diagnóstico por imagem , Lobo Parietal/patologia , Desempenho Psicomotor/fisiologia
3.
Int J Mol Sci ; 23(14)2022 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-35887280

RESUMO

Diseases of the muscle tissue, particularly those disorders which result from the pathology of individual muscle cells, are often called myopathies. The diversity of the content of individual cells is of interest with regard to their role in both biochemical mechanisms and the structure of muscle tissue itself. These studies focus on the preliminary analysis of the differences that may occur between diseased tissues and tissues that have been recognised as a reference group. To do so, 13 samples of biopsied human muscle tissues were studied: 3 diagnosed as dystrophies, 6 as (non-dystrophic) myopathy and 4 regarded as references. From these sets of muscle biopsies, 135 completely measured muscle fibres were separated altogether, which were subjected to investigations using synchrotron radiation X-ray fluorescence (SR-XRF). Muscle fibres were analysed in terms of the composition of elements such as Br, Ca, Cl, Cr, Cu, Fe, K, Mn, P, S and Zn. The performed statistical tests indicate that all three groups (dystrophies-D; myopathies-M; references-R) show statistically significant differences in their elemental compositions, and the greatest impact, according to the multivariate discriminate analysis (MDA), comes from elements such as Ca, Cu, K, Cl and S.


Assuntos
Fibras Musculares Esqueléticas , Síncrotrons , Humanos , Radiografia , Espectrometria por Raios X , Raios X
4.
Int J Mol Sci ; 23(21)2022 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-36362225

RESUMO

The objective of our study was to identify new markers related to excessive body adiposity and its early consequences. For this purpose we determined serum FGF-19 and FGF-21 concentrations in obese rats, whose role in the pathogenesis of obesity is not yet established. In addition, a total reflection X-ray fluorescence technique was applied to determine the elemental chemistry of certain tissues affected by obesity. Next, the new biochemical and molecular parameters were correlated with well-known obesity-related markers of metabolic abnormalities. Our obese rats were characterized by increased calorie consumption and body adiposity, hypercholesterolemia, elevated levels of liver enzymes and FGF-21, while the level of FGF-19 was reduced. Strong relationships between new hormones and established metabolic parameters were observed. Furthermore, we demonstrated that obesity had the greatest effect on elemental composition in the adipose tissue and liver and that rubidium (Rb) had the highest importance in distinguishing the studied groups of animals. Tissue Rb strongly correlated with both well-known and new markers of obesity. In conclusion, we confirmed serum FGF-19 and FGF-21 as useful new markers of obesity-related metabolic alternations and we robustly propose Rb as a novel indicator of excessive body adiposity and its early consequences. However, further investigations are encouraged to address this clinical issue.


Assuntos
Fatores de Crescimento de Fibroblastos , Obesidade , Ratos , Animais , Obesidade/metabolismo , Fatores de Crescimento de Fibroblastos/metabolismo , Adiposidade , Ingestão de Energia , Biomarcadores/metabolismo
5.
Sensors (Basel) ; 21(23)2021 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-34883967

RESUMO

The goal of the work was to investigate the possible application of factor analysis methods for processing X-ray Fluorescence (XRF) data acquired with a full-field XRF spectrometer employing a position-sensitive and energy-dispersive Gas Electron Multiplier (GEM) detector, which provides only limited energy resolution at a level of 18% Full Width at Half Maximum (FWHM) at 5.9 keV. In this article, we present the design and performance of the full-field imaging spectrometer and the results of case studies performed using the developed instrument. The XRF imaging data collected for two historical paintings are presented along with the procedures applied to data calibration and analysis. The maps of elemental distributions were built using three different analysis methods: Region of Interest (ROI), Non-Negative Matrix Factorisation (NMF), and Principal Component Analysis (PCA). The results obtained for these paintings show that the factor analysis methods NMF and PCA provide significant enhancement of selectivity of the elemental analysis in case of limited energy resolution of the spectrometer.

6.
Int J Colorectal Dis ; 34(1): 13-25, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30465238

RESUMO

BACKGROUND: Immunotherapy focuses on selectively enhancing the host's immune response against malignant disease. It has been investigated as an important treatment modality against malignant disease for many years, but until recently its use was mostly limited to a few cancers. The advent of new immunemodulating agents in the recent past has changed the landscape for management of many solid tumors. Currently, immunotherapy offers a valuable, and in many cases, a more effective alternate to the conventional cytotoxic therapy. Colorectal cancer is a leading cause of cancer-related death. Despite progress in systemic therapy, most patients with metastatic colorectal cancer die of their disease. There is an unmet need for more effective treatments for patients with metastatic colorectal cancer. The current data support that colorectal tumors are immunoresponsive and a subset of patients with advanced disease achieve long term benefit with immunotherapy. OBJECTIVES: This review aims to provide the current status of immunotherapy in patients with metastatic colorectal cancer. METHODS: We researched sources published in the English language between January 2000 and August 2018 and listed within the PubMed database using combinations of the key words and reviewed the proceedings of international cancer conferences and current guidelines made by major cancer societies. RESULTS: In this review, we summarize the current status of research on immunotherapy in metastatic colorectal cancer and discuss various treatment modalities including checkpoint inhibitors, cancer vaccines, adoptive cell transfer, oncolytic virus therapy, and various other agents that are under investigation with a special emphasis on immune checkpoint inhibitors. Since the toxicity profile of immunotherapy is very different from conventional cytotoxic agents and could involve any organ system, we briefly review common adverse effects and their management.


Assuntos
Neoplasias Colorretais/secundário , Neoplasias Colorretais/terapia , Imunoterapia/tendências , Animais , Vacinas Anticâncer/imunologia , Neoplasias Colorretais/imunologia , Neoplasias Colorretais/patologia , Humanos , Metástase Neoplásica , Terapia Viral Oncolítica , Vacinação
7.
J Synchrotron Radiat ; 25(Pt 1): 189-203, 2018 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-29271768

RESUMO

The International Atomic Energy Agency (IAEA) jointly with the Elettra Sincrotrone Trieste (EST) operates a multipurpose X-ray spectrometry endstation at the X-ray Fluorescence beamline (10.1L). The facility has been available to external users since the beginning of 2015 through the peer-review process of EST. Using this collaboration framework, the IAEA supports and promotes synchrotron-radiation-based research and training activities for various research groups from the IAEA Member States, especially those who have limited previous experience and resources to access a synchrotron radiation facility. This paper aims to provide a broad overview about various analytical capabilities, intrinsic features and performance figures of the IAEA X-ray spectrometry endstation through the measured results. The IAEA-EST endstation works with monochromatic X-rays in the energy range 3.7-14 keV for the Elettra storage ring operating at 2.0 or 2.4 GeV electron energy. It offers a combination of different advanced analytical probes, e.g. X-ray reflectivity, X-ray absorption fine-structure measurements, grazing-incidence X-ray fluorescence measurements, using different excitation and detection geometries, and thereby supports a comprehensive characterization for different kinds of nanostructured and bulk materials.

8.
Anal Chem ; 88(3): 1661-6, 2016 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-26708500

RESUMO

The X-ray fluorescence imaging technique allows not only the imaging itself but also the identification of the hidden paint layers what makes it much more versatile as compared with X-ray radiography. One of the main disadvantages of the former method is the fact that the characteristic X-rays from the deeper paint layers are absorbed in the covering layers. This effect is manifested by some artifacts that impede a proper interpretation of the acquired images. In this work, it is shown that the methodology for correction of the interlayer absorption effects can be extended to the case of polychromatic excitation. Additionally, a new approach for determination of the optimal correction parameters has also been presented. The methodology was verified using either the test painting or the mock-up painting both measured with a table-top micro-XRF setup.

9.
Biometals ; 29(3): 487-94, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27041114

RESUMO

Most studies have focused on the biodistribution of titanium(IV) oxide as nanoparticles or crystals in organism. But several reports suggested that titanium is released from implant in ionic form. Therefore, gaining insight into toxicokinetics of Ti ions will give valuable information, which may be useful when assessing the health risks of long-term exposure to titanium alloy implants in patients. A micro synchrotron radiation-induced X-ray fluorescence (µ-SRXRF) was utilized to investigate the titanium distribution in the liver, spleen and kidneys of rats following single intravenous or 30-days oral administration of metal (6 mg Ti/b.w.) in ionic form. Titanium was mainly retained in kidneys after both intravenous and oral dosing, and also its compartmentalization in this organ was observed. Titanium in the liver was non-uniformly distributed-metal accumulated in single aggregates, and some of them were also enriched in calcium. Correlation analysis showed that metal did not displace essential elements, and in liver titanium strongly correlated with calcium. Two-dimensional maps of Ti distribution show that the location of the element is characteristic for the route of administration and time of exposure. We demonstrated that µ-SRXRF can provide information on the distribution of titanium in internal structures of whole organs, which helps in enhancing our understanding of the mechanism of ionic titanium accumulation in the body. This is significant due to the popularity of titanium implants and the potential release of metal ions from them to the organism.


Assuntos
Rim/química , Fígado/química , Baço/química , Titânio/farmacocinética , Administração Intravenosa , Administração Oral , Animais , Rim/metabolismo , Fígado/metabolismo , Masculino , Ratos , Ratos Wistar , Espectrometria por Raios X , Baço/metabolismo , Síncrotrons , Distribuição Tecidual , Titânio/administração & dosagem , Titânio/metabolismo
10.
Przegl Lek ; 73(7): 465-71, 2016.
Artigo em Polonês | MEDLINE | ID: mdl-29676888

RESUMO

Introduction: Glomerular filtration rate plays a key role in the diagnosis of chronic kidney disease (CKD). In everyday practice GFR is estimated using equations based on serum creatinine. Commonly used abbreviated MDRD formula is not very precise in patients with mildly impaired renal function, underestimating eGFR when greater than 60 ml/min/1.73 m2. CKD-EPI formula, recommended by KDIGO, might be a good alternative in this situation. The aim of the study was to compare the prevalence of consecutive stages of CKD in the group of patients from Emergency Department having calculated eGFR according MDRD and CKD-EPI formulas Materials and Methods: The retrospective study was performed in the group of 1,452 patients (762 women and 690 men aged 57.4 years ± 19.8 years). Estimated GFR (eGFR) was calculated based on MDRD and CKD-EPI formulas and the obtained results were analyzed according patients location in the consecutive group of CKD, used formulas, sex and age. Results: The mean values of eGFR for both formulas were similar and for MDRD was 68.6 ± 22.3 ml/min/ 1.73 m2 while for CKD-EPI 69.18 ± 24.4 ml/ min/1.73 m2. The highest differences were observed in the early stages of CKD where the calculation of eGFR based on CKD-EPI vs MDRD formula gives an increase of population in stage G1 of CKD by 5.7% (342 vs 241 persons) and reduction by 7.8% (625 vs 737) in the stage G2. Conclusions: Both formulas have the similar value in the estimation of CKD. The differences concerning mainly G1 and G2 stages.


Assuntos
Serviço Hospitalar de Emergência , Insuficiência Renal Crônica/epidemiologia , Adulto , Idoso , Feminino , Taxa de Filtração Glomerular , Humanos , Masculino , Pessoa de Meia-Idade , Polônia , Prevalência , Estudos Retrospectivos
11.
Przegl Lek ; 73(5): 310-5, 2016.
Artigo em Polonês | MEDLINE | ID: mdl-29629748

RESUMO

The prevalence of chronic kidney disease (CKD) in the world is constantly increasing. This is related to the eldering of the societies, growing numbers of patients with diabetes, hypertension, atherosclerosis and obesity. The progress of the disease increases the risk of complications and mortality, especially from cardiovascular causes and leads to end-stage renal disease requiring renal replacement therapy. The analysis involving 1452 patients (762 women and 690 men aged 57.4 years ± 19.8 years) from the Emergency Department in Kielce revealed reduced eGFR below 60 ml/ min/1,73 m2 in 474 (32.6%) of participants and mean values of eGFR was 68.6 ± 22.3 ml/min/1.73 m2. Such high percentage of patients fulfilling criteria of CKD may be due to the fact that to the Emergency Department coming patients with high comorbidity and with increased risk of kidney disease.


Assuntos
Serviço Hospitalar de Emergência/estatística & dados numéricos , Insuficiência Renal Crônica/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Taxa de Filtração Glomerular , Humanos , Masculino , Pessoa de Meia-Idade , Polônia , Prevalência , Adulto Jovem
12.
Przegl Lek ; 73(1): 15-9, 2016.
Artigo em Polonês | MEDLINE | ID: mdl-27120943

RESUMO

INTRODUCTION: Patients with cardiovascular diseases are a group of increased risk of acute kidney injury (AKI). Mortality in this group of patients with AKI, especially treated in intensive care units, is very high. The aim of this study was to evaluate the clinical characteristic of patients with AKI complicated severe cardiovascular diseases. MATERIAL AND METHODS: Retrospective evaluation of 246 questionnaire of patients with AKI in the course of severe cardiovascular diseases treated in the wards of nephrological profile from the malopolska and podkarpackie voivodships in the years 2000-2011 was performed. RESULTS: The group of patients consisted of 157 men and 89 women, with mean age 67.9 ± 14.8 years. The most common cause of AKI were: acute decompensated heart failure--24 (9.8%), chronic decompensated heart failure--94 (38.2%), cardiac arrest--29 (11.8%), myocardial infarction--48 (19.5%), CABG--12 (4.9%), cardiac valve implantation--14 (5.7), heart transplantation--4 (1.6%) and aortic aneurysm--21 (8.5%). Age distribution of patients with AKI revealed that most numerous group had 71-80 years. The most of patients (95.9%) with AKI were treated with hemodialysis. The mortality rate in the study group was very high (69.5%). Recovery of renal function was observed in 39 (27.3%) of patients. Signs of kidney disease before AKI was noted in 116 (47.2%) of patients. CONCLUSIONS: Patients with severe cardiovascular complications and AKI had high mortality rate instead of performed hemodialysis treatment.


Assuntos
Injúria Renal Aguda/etiologia , Aneurisma Aórtico/complicações , Cardiopatias/complicações , Injúria Renal Aguda/mortalidade , Injúria Renal Aguda/terapia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Diálise Renal , Estudos Retrospectivos , Inquéritos e Questionários , Resultado do Tratamento , Adulto Jovem
13.
Przegl Lek ; 72(11): 649-55, 2015.
Artigo em Polonês | MEDLINE | ID: mdl-27012124

RESUMO

With the development of kidney transplantation procedure the number of patients returning to dialysis after losing their graft function is gradually increasing. Early return to dialysis after an unsuccessful kidney transplantation is associated with a worse prognosis. Patients with end stage transplanted kidney failure may be qualified again for the treatment of both peritoneal dialysis or hemodialysis. They represent an increased risk of complications as compared to patients without a history of previous kidney transplantation because they usually have high commorbidity, receive immunosuppressive therapy and during re-qualification to dialysis usually have no efficient vascular access or peritoneal catheter implanted. Graft loss in the early stages after procedure, because of fulminant rejection, vascular thrombosis or lack of primary organ function is associated with immunosuppression withdrawal while leaving a failing kidney is an indication to maintain it in a reduced form. The indication for removal of an inefficient transplant after more than 12 months are: symptoms of its intolerance manifested by acute rejection, pain in the area of the graft, fever, severe anemia, increase of blood pressure and inflammatory markers. Removal of the graft may be associated with a temporary increase in immunization of the patient. Patients meeting the clinical conditions for transplantation should be considered for another kidney transplant as preemptive transplantation or as soon as possible after dialysis start. Although kidney retransplantation results are slightly worse when compared with the first transplant, it still has an advantage over dialysis.


Assuntos
Rejeição de Enxerto , Transplante de Rim , Diálise Renal , Humanos , Falência Renal Crônica/cirurgia , Reoperação
14.
Anal Chem ; 86(22): 11275-80, 2014 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-25307861

RESUMO

The confocal microbeam X-ray fluorescence technique is a well-established analytical tool that is widely used for qualitative and quantitative analysis of stratified materials. There are several different reconstruction methods dedicated to this type of samples. However, these methods are applicable with monochromatic excitation only. The full description of matrix effects and geometrical effects for polychromatic X-ray photons in confocal geometry is a demanding task. In the present paper, this problem was overcome by the use of effective energy approximation. The reduction of the whole energy dimension into one effective value eliminates the necessity of integration over the primary beam energy range for a number of basic parameters. This simplification is attainable without loss of the accuracy of analysis. The proposed approach was validated by applying it to the reconstruction of element concentration depth profiles of stratified standard samples measured with tabletop confocal microbeam X-ray fluorescence setup and by comparing the obtained results of two independent algorithms.

15.
Planta ; 239(6): 1233-42, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24595517

RESUMO

The aim of the study was the analysis of Cr distribution in shoots of the macrophyte Callitriche cophocarpa by means of two X-ray-based techniques: micro X-ray fluorescence (µXRF) and electron probe X-ray microanalysis (EPXMA). Plants were treated with 100 µM (5.2 mg l(-1)) chromium solutions for 7 days. Cr was introduced independently at two speciations as Cr(III) and Cr(VI), known for their diverse physicochemical properties and different influence on living organisms. A comparative analysis of Cr(III)-treated plants by EPXMA and µXRF demonstrated high deposition of Cr in epidermal glands/hairs localized on leaves and stems of the plant shoots. Cr in Cr(III)-treated plants was recorded solely in glands/hairs, and the element was not present in any other structures. On the other hand, Cr in Cr(VI)-treated group of plants was rather found in vascular bundles. Moreover, the concentration of Cr in Cr(VI)-treated plants was significantly lower than in plants incubated in Cr(III) solution. The results obtained in this work suggest differences in chromium uptake, transport and accumulation dependent on the oxidative state of the element.


Assuntos
Cromo/metabolismo , Brotos de Planta/metabolismo , Plantas/metabolismo , Animais , Cromo/química , Folhas de Planta/química , Folhas de Planta/metabolismo , Brotos de Planta/química , Caules de Planta/química , Caules de Planta/metabolismo
16.
Polymers (Basel) ; 16(6)2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38543348

RESUMO

The effect of particle size and oxidation degree of new carbon microfillers, based on coal pitch (CP) and petroleum pitch (PET) cokes, on the structure as well as thermal, mechanical, and electrical properties of the composites based on ultrahigh molecular weight polyethylene (UHMWPE) was investigated. The composites studied have a segregated structure of filler particle distribution in the UHMWPE matrix. It was found that composite with smaller CP grain fraction has the highest Young's modulus and electrical conductivity compared to the other composites studied, which can be the result of a large contribution of flake-shaped particles. Additionally, conductivity of this composite turned out to be similar to composites with well-known carbon nanofillers, such as graphene, carbon black, and CNTs. Additionally, the relationship between electrical conductivity and Young's modulus values of composites studied was revealed, which indicates that electrical conductivity is very sensitive to the structure of the filler phase in the polymer matrix. In general, it was established that the properties, especially the electrical conductivity, of the composites studied strongly depends on the size, shape, and oxidative treatment of CP and PET filler particles, and that the CP coke of appropriately small particle sizes and flake shape has significant potential as a conductive filler for polymer composites.

17.
Sci Rep ; 14(1): 1254, 2024 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-38218977

RESUMO

Glioblastoma (GBM) is a fast-growing and aggressive brain tumor which invades the nearby brain tissue but generally does not spread to the distant organs. Nonetheless, if untreated, GBM can result in patient death in time even less than few months from the diagnosis. The influence of the tumor progress on organs other than brain is obvious but still not well described. Therefore, we examined the elemental abnormalities appearing in selected body organs (kidney, heart, spleen, lung) in two rat models of GBM. The animals used for the study were subjected to the implantation of human GBM cell lines (U87MG and T98G) characterized by different levels of invasiveness. The elemental analysis of digested organ samples was carried out using the total reflection X-ray fluorescence (TXRF) method, independently, in three European laboratories utilizing various commercially available TXRF spectrometers. The comparison of the data obtained for animals subjected to T98G and U87MG cells implantation showed a number of elemental anomalies in the examined organs. What is more, the abnormalities were found for rats even if neoplastic tumor did not develop in their brains. The most of alterations for both experimental groups were noted in the spleen and lungs, with the direction of the found element changes in these organs being the opposite. The observed disorders of element homeostasis may result from many processes occurring in the animal body as a result of implantation of cancer cells or the development of GBM, including inflammation, anemia of chronic disease or changes in iron metabolism. Tumor induced changes in organ elemental composition detected in cooperating laboratories were usually in a good agreement. In case of elements with higher atomic numbers (Fe, Cu, Zn and Se), 88% of the results were classified as fully compliant. Some discrepancies between the laboratories were found for lighter elements (P, S, K and Ca). However, also in this case, the obtained results fulfilled the requirements of full (the results from three laboratories were in agreement) or partial agreement (the results from two laboratories were in agreement).


Assuntos
Glioblastoma , Humanos , Ratos , Animais , Fluorescência , Raios X , Encéfalo , Homeostase
18.
Brain Commun ; 6(3): fcae122, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38712322

RESUMO

The concept of brain reserve capacity has emerged in stroke recovery research in recent years. Imaging-based biomarkers of brain health have helped to better understand outcome variability in clinical cohorts. Still, outcome inferences are far from being satisfactory, particularly in patients with severe initial deficits. Neurorehabilitation after stroke is a complex process, comprising adaption and learning processes, which, on their part, are critically influenced by motivational and reward-related cognitive processes. Amongst others, dopaminergic neurotransmission is a key contributor to these mechanisms. The question arises, whether the amount of structural reserve capacity in the dopaminergic system might inform about outcome variability after severe stroke. For this purpose, this study analysed imaging and clinical data of 42 severely impaired acute stroke patients. Brain volumetry was performed within the first 2 weeks after the event using the Computational Anatomy Toolbox CAT12, grey matter volume estimates were collected for seven key areas of the human dopaminergic system along the mesocortical, mesolimbic and nigrostriatal pathways. Ordinal logistic regression models related regional volumes to the functional outcome, operationalized by the modified Rankin Scale, obtained 3-6 months after stroke. Models were adjusted for age, lesion volume and initial impairment. The main finding was that larger volumes of the amygdala and the nucleus accumbens at baseline were positively associated with a more favourable outcome. These data suggest a link between the structural state of mesolimbic key areas contributing to motor learning, motivational and reward-related brain networks and potentially the success of neurorehabilitation. They might also provide novel evidence to reconsider dopaminergic interventions particularly in severely impaired stroke patients to enhance recovery after stroke.

19.
Spectrochim Acta A Mol Biomol Spectrosc ; 297: 122717, 2023 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-37080053

RESUMO

Ovarian cancer is one of the deadliest cancers occurring in women. This is typically due to late diagnosis of the disease and difficult treatment. Infrared microspectroscopy is a complementary research method that can be helpful in the diagnosis of this disease, because it allows for the analysis of the tissues biomolecular composition. In this study, archival paraffin-embedded preparations of ovarian tissues, tumours and control, were used. However, the paraffin present in such specimens is a strong absorber of infrared radiation, which makes it impossible to reliably analyse the biomolecular composition of the sample. The solution to this problem is to deparaffinize the tissue before the analysis. However, the extend to which the paraffinization and deparaffinization processes influence the biomolecular composition of the tissues is unclear. Analysed tissues in the form of cores were placed in a paraffin micromatrix and FTIR measurements were performed. Then the samples were deparaffinized and the measurements were taken again. For both sets of samples (embedded in paraffin and deparaffinized) ratios of integrated peaks and massifs within the obtained spectra were calculated. The obtained ratios were compared for different types of diseased and healthy, control tissues. The Kruskal-Wallis test revealed statistically significant differences of the calculated ratios between most of the types of tissues. Random Forest models clearly showed that both samples in paraffin and deparaffinized retain enough information to classify the tissues reliably. The feature analysis revealed the most important feature for distinguishing between different types of samples, i.e. 1080 cm-1/1240 cm-1 ratio and lipid saturation for the samples embedded in paraffin and deparaffinized respectively. The study showed that the deparaffinization process leads to changes in the biomolecular composition of the analysed tissues. Despite this, classification of the tissues based on FTIR measurements remains possible.


Assuntos
Neoplasias Ovarianas , Parafina , Feminino , Humanos , Análise de Fourier , Neoplasias Ovarianas/diagnóstico , Espectroscopia de Infravermelho com Transformada de Fourier/métodos
20.
Artigo em Inglês | MEDLINE | ID: mdl-37971709

RESUMO

Views on the etiopathogenesis of atherosclerosis are subject to evolution. In addition to the classic well-known risk factors, new ones related to mental state, social life and environment are being discovered. Both acute and chronic stress stimulate inflammatory processes. Due to the change in lifestyle and eating habits, the accumulation of risk factors in childhood is an increasing problem. Knowledge of risk factors allows for effective primary prevention of cardiovascular diseases. The effectiveness of prevention increases when the activities cover the largest possible part of the society, and access to a doctor is easy. Therefore, government programs are being implemented offering patients easier access to diagnostics of cardiovascular diseases at the level of primary health care, which enables faster identification of people at the greatest cardiovascular risk. Easier access to primary care and a good doctor-patient relationship improve patient compliance. In this situation, the importance of the family doctor as a key link in the diagnosis, prevention and treatment of cardiovascular diseases is increasing.

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