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1.
J Cancer Res Clin Oncol ; 147(1): 129-138, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32951068

RESUMO

PURPOSE: To investigate the mRNA expression of B-MYB and MDM2 together with their p53 relatedness in clear cell renal cell carcinoma (ccRCC). METHODS: Genes were screened for their mRNA expression from 529 patients in a publicly available ccRCC cohort (TCGA). A cohort of 101 patients with ccRCC served as validation by qRT-PCR mRNA tissue expression analysis. RESULTS: Expression: B-MYB expression was significantly higher in high-grade tumours (p < 0.0001 and p = 0.048) and in advanced stages (p = 0.005 and p = 0.037) in both cohorts. Correlation: p53-B-MYB as well as MDM2-B-MYB showed significant correlations in local and low-grade ccRCCs, but not in high grade tumours or advanced stages (r < 0.3 and/or p > 0.05). Survival: Multivariable Cox regression of the TCGA cohort revealed B-MYB upregulation and low MDM2 expression as predictors for an impaired overall survival (OS) (HR 1.97; p = 0.0003; HR 2.94, p < 0.0001) and progression-free survival (PFS) (HR 2.86; p = 0.0005; HR 1.58, p = 0.046). In the validation cohort, the results were confirmed for OS by univariable, but not multivariable regression: high B-MYB expression (HR = 3.05, p = 0.035) and low MDM2 expression (HR 3.81, p value 0.036). CONCLUSION: In ccRCC patients with high-grade tumours and advanced stages, high B-MYB expression is common and is associated with poorer OS and PFS. These patients show a loss of their physiological B-MYB-p53 network correlation, suggesting an additional, alternative regulatory, oncogenic mechanism. Assuming further characterization of its signalling pathways, B-MYB could be a potential therapy target for ccRCC.


Assuntos
Biomarcadores Tumorais/metabolismo , Carcinoma de Células Renais/patologia , Proteínas de Ciclo Celular/metabolismo , Regulação Neoplásica da Expressão Gênica , Neoplasias Renais/patologia , Transativadores/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Idoso , Biomarcadores Tumorais/genética , Carcinoma de Células Renais/genética , Carcinoma de Células Renais/metabolismo , Proteínas de Ciclo Celular/genética , Progressão da Doença , Feminino , Seguimentos , Humanos , Neoplasias Renais/genética , Neoplasias Renais/metabolismo , Masculino , Pessoa de Meia-Idade , Prognóstico , Taxa de Sobrevida , Transativadores/genética , Proteína Supressora de Tumor p53/genética
2.
Pathologe ; 40(Suppl 3): 259-264, 2019 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-31720747

RESUMO

Hyperosmolar micromilieu has been observed in physiologic (kidney medulla, lymphatic tissue) and pathologic (renal allorejection, solid tumors) conditions. Hyperosmolarity can modulate gene expression and alter the stimulatory profile of macrophages and dendritic cells. We have reported that dendritic cells upon exposure to hypertonic stimuli shift their profile towards a macrophage-M2-like phenotype, resulting in attenuated local alloreactivity during acute kidney graft rejection. Moreover, we showed that a hyperosmotic microenvironment affects the cross-priming capacity of dendritic cells. Using ovalbumin as a model antigen, we showed that exposure of dendritic cells to hyperosmolarity strongly inhibits activation of antigen-specific T cells despite enhancement of antigen uptake, processing, and presentation; it can reduce dendritic cell-T cell contact time. We have identified TRIF as key mediator of this phenomenon. Moreover, we detected a hyperosmolarity-triggered, TRIF-dependent clustering of MHC class I­antigen complexes, but not of unloaded MHCI molecules, providing a possible explanation for a reduced T cell activation. Our findings identify dendritic cells as important players in hyperosmolarity-triggered immune imbalance and suggest that targeting local hyperosmolarity in tumor micromilieu may contribute to an enhanced specific anti-tumor immune response.


Assuntos
Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Células Dendríticas , Antígenos de Histocompatibilidade Classe I , Apresentação Cruzada , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/imunologia , Antígenos de Histocompatibilidade Classe I/metabolismo , Humanos , Ativação Linfocitária , Osmorregulação , Ovalbumina/imunologia , Linfócitos T
3.
Spectrochim Acta A Mol Biomol Spectrosc ; 216: 173-178, 2019 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-30897378

RESUMO

In investigation of (patho)physiological processes, cells represent frequently used analyte as an exceptional source of information. However, spectroscopic analysis of live cells is still very seldom in clinics, as well as in research studies. Among others, the reasons are long acquisition time during which autolysis process is activated, necessity of specified technical equipment, and inability to perform analysis in a moment of sample preparation. Hence, an optimal method of preserving cells in the existing state is of extreme importance, having in mind that selection of fixative is cell lineage dependent. In this study, two commonly used chemical fixatives, formaldehyde and methanol, are used for preserving primary mesenchymal stem cells extracted from periodontal ligament, which are valuable cell source for reconstructive dentistry. By means of Raman spectroscopy, cell samples were probed and the impact of these fixatives on their Raman response was analyzed and compared. Different chemical mechanisms are the core processes of formaldehyde and methanol fixation and certain Raman bands are shifted and/or of changed intensity when Raman spectra of cells fixed in that manner are compared. In order to get clearer picture, comprehensive statistical analysis was performed.


Assuntos
Fixadores/química , Formaldeído/química , Células-Tronco Mesenquimais/química , Metanol/química , Análise Espectral Raman/métodos , Fixação de Tecidos/métodos , Separação Celular , Células Cultivadas , Humanos , Células-Tronco Mesenquimais/citologia , Ligamento Periodontal/química , Ligamento Periodontal/citologia
4.
Spectrochim Acta A Mol Biomol Spectrosc ; 213: 384-390, 2019 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-30726762

RESUMO

We have employed micro-Raman spectroscopy to get insight into intrinsic biomolecular profile of individual mesenchymal stem cell isolated from periodontal ligament. Furthermore, these cells were stimulated towards adipogenic, chondrogenic, and osteogenic lineages and their status of differentiation was assessed using micro-Raman spectroscopy. In both cases, glass coverslips were used as substrates, due to their wide availability and cost effectiveness. In all sample groups, the same type of behavior was observed, manifested as changes in Raman spectra: the increase of relative intensity of protein/lipid bands and decrease of nucleic acid bands. Comprehensive statistical analysis in the form of principal component analysis was performed, which revealed noticeable grouping of cells with the similar features. Despite the inhomogeneity of primary stem cells and their differentiated lineages, we demonstrated that micro-Raman spectroscopy is sufficient for distinguishing cells' status, which can be valuable for medical and clinical application.


Assuntos
Diferenciação Celular , Células-Tronco Mesenquimais/citologia , Análise Espectral Raman/métodos , Adolescente , Adulto , Linhagem da Célula , Células Cultivadas , Humanos , Microespectrofotometria , Ligamento Periodontal/citologia , Análise de Componente Principal , Adulto Jovem
5.
J Phys Condens Matter ; 28(48): 485401, 2016 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-27705954

RESUMO

Polarized Raman scattering spectra of the K x Co2-y Se2 single crystals reveal the presence of two phonon modes, assigned as of the A 1g and B 1g symmetry. The absence of additional modes excludes the possibility of vacancy ordering, unlike in K x Fe2-y Se2. The ferromagnetic (FM) phase transition at [Formula: see text] K leaves a clear fingerprint on the temperature dependence of the Raman mode energy and linewidth. For [Formula: see text] the temperature dependence looks conventional, driven by the thermal expansion and anharmonicity. The Raman modes are rather broad due to the electron-phonon coupling increased by the disorder and spin fluctuation effects. In the FM phase the phonon frequency of both modes increases, while an opposite trend is seen in their linewidth: the A 1g mode narrows in the FM phase, whereas the B 1g mode broadens. We argue that the large asymmetry and anomalous frequency shift of the B 1g mode is due to the coupling of spin fluctuations and vibration. Our density functional theory (DFT) calculations for the phonon frequencies agree rather well with the Raman measurements, with some discrepancy being expected since the DFT calculations neglect the spin fluctuations.

6.
J Phys Condens Matter ; 27(48): 485701, 2015 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-26569081

RESUMO

Polarized Raman scattering spectra of superconducting K(x)Fe(2-y)Se2 and non-superconducting K0.8Fe1.8Co0.2Se2 single crystals were measured in the temperature range from 10 K up to 300 K. Two Raman active modes from the I4/mmm phase and seven from the I4/m phase are observed in the frequency range from 150 to 325 cm(-1) in both compounds, suggesting that the K0.8Fe1.8Co0.2Se2 single crystal also has a two-phase nature. The temperature dependence of the Raman mode energy is analyzed in terms of lattice thermal expansion and phonon-phonon interaction. The temperature dependence of the Raman mode linewidth is dominated by temperature-induced anharmonic effects. It is shown that the change in Raman mode energy with temperature is dominantly driven by thermal expansion of the crystal lattice. An abrupt change of the A1g mode energy near T(C) was observed in K(x)Fe(2-y) Se2, whereas it is absent in non-superconducting K0.8Fe1.8Co0.2Se2. Phonon energy hardening at low temperatures in the superconducting sample is a consequence of superconductivity-induced redistribution of the electronic states below the critical temperature.

7.
Artigo em Inglês | MEDLINE | ID: mdl-24608014

RESUMO

We report the low-temperature Raman scattering study of racemic ibuprofen. Detailed analysis of the racemic ibuprofen crystal symmetry, related to the vibrational properties of the system, has been presented. The first principle calculations of a single ibuprofen molecule dynamical properties are compered with experimental data. Nineteen, out of 26 modes expected for the spectral region below 200cm(-1), have been observed.


Assuntos
Analgésicos não Narcóticos/química , Ibuprofeno/química , Temperatura Baixa , Modelos Moleculares , Análise Espectral Raman/métodos
8.
J Phys Condens Matter ; 24(45): 456001, 2012 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-23073080

RESUMO

We have measured the magnetization of undoped and Fe(2+/3+) doped CeO(2-y) nanocrystals at various temperatures and magnetic fields. The Stoner condition N(0)I > 1 is multiply fulfilled in the case of nano-CeO(2-y), favoring the band ferromagnetism approach. In the case of Fe-doped samples, the magnetization versus magnetic field dependence is well fitted with a weighted Langevin function. A blocking temperature of about 20 K is obtained both from the ZFC/FC curves and from the coercive field against temperature dependence. The temperature and field dependence of the magnetization clearly shows the presence of nanosized particles which exhibit superparamagnetic behavior.

9.
J Phys Condens Matter ; 24(25): 255402, 2012 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-22641007

RESUMO

The lattice dynamics of FeSb(2) is investigated by first-principles density functional theory calculations and Raman spectroscopy. All Raman- and infrared-active phonon modes are properly assigned. The calculated and measured phonon energies are in good agreement. We have observed strong mixing of the A(g) symmetry modes, with the intensity exchange in the temperature range 210 and 260 K. The A(g) mode repulsion increases by doping FeSb(2) with Co, with no signatures of the electron-phonon interaction for these modes.

10.
J Phys Condens Matter ; 24(13): 135402, 2012 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-22406874

RESUMO

The phonon properties of CoSb(2) have been investigated by Raman scattering spectroscopy and lattice dynamics calculations. Sixteen out of eighteen Raman active modes predicted by factor-group analysis are experimentally observed and assigned. The calculated and measured phonon energies at the Γ point are in very good agreement. The temperature dependence of the A(g) symmetry modes is well represented by phonon-phonon interactions without contribution from any other phonon or electron related interactions.


Assuntos
Antimônio/química , Cobalto/química , Fônons , Cristalografia por Raios X , Elétrons , Modelos Químicos , Análise Espectral Raman , Temperatura , Vibração
11.
Opt Express ; 16(3): 1413-22, 2008 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-18542215

RESUMO

The design of electromagnetic invisibility cloaks is based on singular mappings prescribing zero or infinite values for material parameters on the inner surface of the cloak. Since this is only approximately feasible, an asymptotic analysis is necessary for a sound description of cloaks. We adopt a simple and effective approach for analyzing electromagnetic cloaks - instead of the originally proposed singular mapping, nonsingular mappings asymptotically approaching the ideal one are considered. Scattering and radiation from this type of imperfect cylindrical cloaks is solved analytically and the results are confirmed by full-wave finite element simulations. Our analysis sheds more light on the influence of this kind of imperfection on the cloaking performance and further explores the physics of cloaking devices.


Assuntos
Algoritmos , Campos Eletromagnéticos , Modelos Teóricos , Radiometria/métodos , Medidas de Segurança , Simulação por Computador , Doses de Radiação , Espalhamento de Radiação
12.
Heart ; 94(10): 1295-301, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17690158

RESUMO

BACKGROUND: Abnormal papillary muscles (PM) are often found in hypertrophic cardiomyopathy (HCM). OBJECTIVE: To assess the relationship between morphological alterations of PM in patients with HCM and left ventricular outflow tract (LVOT) obstruction, using magnetic resonance imaging (MRI) and echocardiography. METHODS: Fifty-six patients with HCM (mean age 42 years (interquartile range 27, 51), 70% male) and 30 controls (mean age (42 (30, 53) years, 80% male) underwent MRI on a 1.5 T scanner (Siemens, Erlangen, Germany). Standard cine images were obtained in short-axis (base to apex), along with two-, three- and four-chamber views. The presence of bifid PM (none, one or both) and anteroapical displacement of anterolateral PM was recorded by MRI and correlated with resting LVOT gradients obtained by echocardiography. RESULTS: Double bifid PM (70% vs 17%) and anteroapical displacement of anterolateral PM (77% vs 17%) were more prevalent in patients with HCM than in controls (p<0.001). Subjects with anteroapically displaced PM and double bifid PM had higher resting LVOT gradients than controls (45 (6, 81) vs 12 (0, 12) mm Hg (p<0.01) and 42 (6, 64) vs 11 (0, 17) mm Hg (p = 0.02), respectively. In patients with HCM, the odds ratio of having significant (>or=30 mm Hg) peak resting gradient was 7.1 (95% CI 1.4 to 36.7) for anteroapically displaced anterolateral PM and 10.4 (95% CI 1.2 to 91.2) for double bifid PM (both p = 0.005), independent of septal thickness, use of beta-blockers and/or calcium blockers and resting heart rate. CONCLUSIONS: Patients with HCM with abnormal PM have a higher degree of resting LVOT gradient, which is independent of septal thickness.


Assuntos
Cardiomiopatia Hipertrófica/patologia , Músculos Papilares/patologia , Obstrução do Fluxo Ventricular Externo/patologia , Adulto , Ecocardiografia , Feminino , Humanos , Angiografia por Ressonância Magnética , Masculino , Pessoa de Meia-Idade
13.
J Phys Condens Matter ; 18(32): 7779-87, 2006 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-21690887

RESUMO

Polarized Raman spectra of the strontium vanadium oxide bronze ß-Sr(0.33)V(2)O(5) are measured in the temperature range between 300 and 77 K. The charge ordering phase transition at about 165 K is characterized by the appearance of new Raman-active modes in the spectra, as well as through an abrupt change of the phonon frequencies and dampings. The Raman scattering spectra of ß-Sr(0.33)V(2)O(5) in the charge disordered phase are in apparent resemblance with those of α'-NaV(2)O(5), which suggests that there is a similar charge-phonon dynamics in both compounds. We also suggest that the electrons are delocalized into V(1)-O(5)-V(3) orbitals in the mixed valence state of ß-Sr(0.33)V(2)O(5).

14.
Histopathology ; 38(4): 338-43, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11318899

RESUMO

AIMS: No study has directly compared different histomorphometric methods of quantification of myocardial fibrosis. Therefore we compared the results of semiquantitative, point-counting and computer-based methods in the assessement of myocardial fibrosis in a consecutive series of endomyocardial biopsy samples from patients with heart muscle disease. METHODS AND RESULTS: Histological samples (at least three per patient) were obtained by endomyocardial biopsy from 11 patients with focal myocarditis and from 24 ambulatory patients with idiopathic dilated cardiomyopathy, or during surgery in 10 patients who underwent partial left ventriculectomy. Samples were cut and stained with Masson-trichrome for better contrast. From each sample, a representative field was digitized, and the amount of fibrosis was assessed by semiquantitative scoring, by point-counting, and by computer-based software. Semiquantitative scoring correlated with both point-counting (Spearman's r = 0.69, P < 0.0001) and computer-based (Spearman's r = 0.83, P < 0.0001) methods. There was also a good correlation between point-counting and computer-based methods (r = 0.71, P < 0.0001). However, when compared with the point-counting method, the computer-based method overestimated percent fibrosis by 3.0 +/- 6.7% (P = 0.004). This overestimation correlated with the mean percent fibrosis (r = 0.38, P = 0.014). CONCLUSIONS: Our data show good correlations between the three methods of myocardial fibrosis assessment. However, systematic differences between them emphasize that this should be taken into consideration when comparing results of the studies using different methods of fibrosis assessment.


Assuntos
Cardiomiopatias/patologia , Ecocardiografia/métodos , Fibrose Endomiocárdica/patologia , Processamento de Imagem Assistida por Computador , Biópsia , Cardiomiopatia Dilatada/diagnóstico , Contagem de Células/métodos , Interpretação Estatística de Dados , Ecocardiografia/estatística & dados numéricos , Fibrose Endomiocárdica/diagnóstico , Humanos , Miocardite/patologia , Variações Dependentes do Observador , Reprodutibilidade dos Testes
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