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1.
Sci Rep ; 13(1): 8312, 2023 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-37221188

RESUMO

We present a Lie algebraic approach to a Hamiltonian class covering driven, parametric quantum harmonic oscillators where the parameter set-mass, frequency, driving strength, and parametric pumping-is time-dependent. Our unitary-transformation-based approach provides a solution to our general quadratic time-dependent quantum harmonic model. As an example, we show an analytic solution to the periodically driven quantum harmonic oscillator without the rotating wave approximation; it works for any given detuning and coupling strength regime. For the sake of validation, we provide an analytic solution to the historical Caldirola-Kanai quantum harmonic oscillator and show that there exists a unitary transformation within our framework that takes a generalized version of it onto the Paul trap Hamiltonian. In addition, we show how our approach provides the dynamics of generalized models whose Schrödinger equation becomes numerically unstable in the laboratory frame.

2.
J Environ Radioact ; 196: 15-21, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30368197

RESUMO

Cosmogenic radionuclides in the one-million-year half-life range, like 10Be, find application fields in several Sciences. They are powerful tools in Geology and Geochronology, as they are very important tracers on the Earth, being utilized as chronometer. Meteoric 10Be (T1/2 = 1.39 × 106 y) associated to aerosols can be used as a tracer of atmospheric processes and specifically as indicators of the cosmogenic interactions in lower Stratosphere, upper Troposphere, the air exchange between both and deposition processes on the Earth surface. The applications of 10Be are even more relevant when combined with other radionuclides such as 26Al. In order to provide new data about concentration 10Be in this type of samples, the first atmospheric air filters in Spain have been analysed. Values around 104 at/m3 (atoms per cubic meter of air) for 10Be have been obtained. Due to the location and the features of the sampling site (urban area, at sea level and mid latitude), a new radiochemical procedure was designed and developed in our laboratory for the Accelerator Mass Spectrometry (AMS) measurement of 10Be in this kind of samples. The samples were measured in SARA, the 1 MV AMS system at Centro Nacional de Aceleradores (CNA).


Assuntos
Poluentes Radioativos do Ar/análise , Berílio/análise , Monitoramento de Radiação , Radioisótopos/análise , Aerossóis/análise , Atmosfera/química , Cidades , Espanha
3.
Br J Cancer ; 112(12): 1944-50, 2015 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-25989272

RESUMO

BACKGROUND: There is evidence that tumour-stroma interactions have a major role in the neoplastic progression of pancreatic ductal adenocarcinoma (PDAC). Tumour budding is thought to reflect the process of epithelial-mesenchymal transition (EMT); however, the relationship between tumour buds and EMT remains unclear. Here we characterize the tumour-budding- and stromal cells in PDAC at protein and mRNA levels concerning factors involved in EMT. METHODS: mRNA in situ hybridisation and immunostaining for E-cadherin, ß-catenin, SNAIL1, ZEB1, ZEB2, N-cadherin and TWIST1 were assessed in the main tumour, tumour buds and tumour stroma on multipunch tissue microarrays from 120 well-characterised PDACs and associated with the clinicopathological features, including peritumoural (PTB) and intratumoural (ITB) budding. RESULTS: Tumour-budding cells showed increased levels of ZEB1 (P<0.0001) and ZEB2 (P=0.0119) and reduced E-cadherin and ß-catenin (P<0.0001, each) compared with the main tumour. Loss of membranous ß-catenin in the main tumour (P=0.0009) and tumour buds (P=0.0053), without nuclear translocation, as well as increased SNAIL1 in tumour and stromal cells (P=0.0002, each) correlated with high PTB. ZEB1 overexpression in the main tumour-budding and stromal cells was associated with high ITB (P=0.0084; 0.0250 and 0.0029, respectively) and high PTB (P=0.0005; 0.0392 and 0.0007, respectively). ZEB2 overexpression in stromal cells correlated with higher pT stage (P=0.03), lymphatic invasion (P=0.0172) and lymph node metastasis (P=0.0152). CONCLUSIONS: In the tumour microenvironment of phenotypically aggressive PDAC, tumour-budding cells express EMT hallmarks at protein and mRNA levels underlining their EMT-type character and are surrounded by stromal cells expressing high levels of the E-cadherin repressors ZEB1, ZEB2 and SNAIL1, this being strongly associated with the tumour-budding phenotype. Moreover, our findings suggest the existence of subtypes of stromal cells in PDAC with phenotypical and functional heterogeneity.


Assuntos
Carcinoma Ductal Pancreático/patologia , Proteínas de Homeodomínio/biossíntese , Neoplasias Pancreáticas/patologia , RNA Mensageiro/metabolismo , Proteínas Repressoras/biossíntese , Células Estromais/patologia , Fatores de Transcrição/biossíntese , Caderinas/metabolismo , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/metabolismo , Transição Epitelial-Mesenquimal , Proteínas de Homeodomínio/genética , Humanos , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Fenótipo , RNA Mensageiro/genética , Proteínas Repressoras/genética , Fatores de Transcrição da Família Snail , Fatores de Transcrição/genética , Microambiente Tumoral , Homeobox 2 de Ligação a E-box com Dedos de Zinco , Homeobox 1 de Ligação a E-box em Dedo de Zinco
4.
Lung Cancer ; 69(3): 289-95, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20089328

RESUMO

INTRODUCTION: The aim of our study was to determine the integrity of the cell-cell adhesion E-cadherin-beta-catenin complex in neuroendocrine lung tumors (NELTs) and the possible involvement of Snail in its deregulation. METHODS: The studied series consisted of formalin-fixed-paraffin-embedded tissue samples from 70 patients diagnosed with NELT (2000-2006) including tumors of low malignancy potential (3 tumorlets, 33 typical carcinoids), intermediate malignancy potential (3 atypical carcinoids) and tumors of high malignancy potential (10 large cell neuroendocrine carcinomas-LCNEC and 21 small cell carcinoma-SCLC). E-cadherin, beta-catenin and Snail expression were immunohistochemically evaluated and mRNA levels were assessed by Q-RT-PCR for E-cadherin and Snail. RESULTS: Nuclear Snail signal was high in 46% tumors with the strongest level observed in high malignancy tumors. Furthermore, Snail levels correlated with tumor size, lymph node involvement and tobacco consumption. E-cadherin expression was downregulated in 24% cases and it was absent from the membrane in 31%, all of them cases of high malignancy potential. High E-cadherin levels and a membrane pattern were associated with tumor-free lymph node patients and inversely proportional to Snail protein expression. beta-catenin levels were weak in 43% and absent from the membrane in 59% cases. Interestingly, among high malignancy potential tumors, beta-catenin levels were significantly higher in LCNEC than in SCLC. The integrity of the E-cadherin-beta-catenin complex was retained in 37% cases, most of them carcinoid tumors, and correlated with low Snail levels, low malignancy potential and free lymph nodes. CONCLUSION: Snail nuclear expression and loss of integrity of cell adhesion complex E-cadherin/beta-catenin parallels higher malignancy potential in NELTs.


Assuntos
Caderinas/metabolismo , Carcinoma Neuroendócrino/genética , Núcleo Celular/metabolismo , Neoplasias Pulmonares/genética , Fatores de Transcrição/metabolismo , Transporte Ativo do Núcleo Celular , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Caderinas/genética , Carcinoma Neuroendócrino/diagnóstico , Carcinoma Neuroendócrino/metabolismo , Carcinoma Neuroendócrino/patologia , Carcinoma Neuroendócrino/fisiopatologia , Adesão Celular/genética , Progressão da Doença , Feminino , Humanos , Imuno-Histoquímica , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/fisiopatologia , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Fumar , Fatores de Transcrição da Família Snail , Fatores de Transcrição/genética , beta Catenina/metabolismo
5.
Autoimmunity ; 40(2): 103-7, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17364501

RESUMO

BACKGROUND: Celiac Disease (CD) is present in 1-16.4% of patients with type 1 diabetes mellitus. The most important serological markers of CD are anti-endomysial (EMA), anti-tissue transglutaminase (tTGA) and antigliadin antibodies (AGA). AIM/HYPOTHESIS: The objective of this work is to determine the frequency of tTGA and/or AGA in latent autoimmune diabetes of adult (LADA) and subjects with type 2 diabetes (T2DM), as well as to evaluate their relation with several clinical and biochemical characteristics. SUBJECTS AND METHODS: Forty three subjects with LADA and 99 with T2DM were studied. The presence of AGA, tTGA was determined in the sera of these patients. The variables: sex, age, duration of diabetes, treatment, body mass index (BMI) and fasting blood glucose concentration were also recorded. RESULTS: No differences were found in the frequency of celiac disease associated antibodies between LADA and T2DM subjects. The presence of celiac disease related antibodies was more frequent in patients with a normal or low BMI. CONCLUSIONS: Celiac disease does not seem to be related with pancreatic autoimmunity in type 2 diabetes. Celiac disease causes a decrease of body mass index in type 2 diabetes while pancreatic islet autoimmunity in this entity masks this effect.


Assuntos
Autoanticorpos/imunologia , Doença Celíaca/imunologia , Diabetes Mellitus Tipo 1/imunologia , Diabetes Mellitus Tipo 2/imunologia , Adulto , Idoso , Índice de Massa Corporal , Feminino , Gliadina/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Transglutaminases/imunologia
6.
Clin Exp Immunol ; 133(3): 422-9, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12930370

RESUMO

Coeliac disease (CD) is described as an autoimmune enteropathy associated with the presence of IgG and IgA antigliadin and antitransglutaminase autoantibodies. While of diagnostic significance, the role of these autoantibodies in the immunopathogenesis of CD is elucidated. An inappropriate T cell immune response to gluten is also involved in the pathogenesis of CD, as evidenced by autoantibody switching. The N-glycans released from serum IgG of CD patients and three groups of healthy controls, of differing age ranges, were analysed by NH2-high performance liquid chromatography (HPLC). The fucosylated biantennary N- glycans were the most abundant neutral oligosaccharides; in particular, the agalacto form (G0F) showed a mean value of 42% (s.d. +/- 7.4), 30% (s.d. +/- 5.9), 26% (s.d. +/- 4.2) and 35% (s.d. +/- 6.8) for CD patients, healthy children, healthy adults under 40 and healthy adults over 40 years old, respectively. The ratio of asialo agalacto fucosylated biantenna to asialo monogalacto fucosylated biantenna (G0F)/(G1F) for CD patients showed a significant increase compared to healthy children (P < 0.0002), healthy adults under 40 (P < 0.0002) and healthy adults over 40 years old (P < 0.01). Hypogalactosylation was more pronounced for CD patients than for the patients with other autoimmune diseases such as rheumatoid arthritis or psoriatic arthritis.


Assuntos
Doenças Autoimunes/imunologia , Doença Celíaca/imunologia , Imunoglobulina G/metabolismo , Polissacarídeos/análise , Adulto , Autoanticorpos/análise , Estudos de Casos e Controles , Criança , Pré-Escolar , Cromatografia Líquida de Alta Pressão/métodos , Gliadina/imunologia , Humanos , Lactente , Oligossacarídeos/análise , Transglutaminases/imunologia
7.
Clin Chim Acta ; 284(1): 93-100, 1999 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-10437647

RESUMO

Elastase levels are an important marker of the extent and severity of inflammatory processes. We describe a visual immunoassay based on two monoclonal antibodies for the semi-quantitative determination of plasma elastase levels. The method is rapid, reliable, easy to perform, and does not require special laboratory equipment. There is coincidence of our results with those obtained by quantitative methods. The assay is suitable to obtain information for the management of patients in most intensive care units.


Assuntos
Imunoensaio/métodos , Elastase de Leucócito/sangue , Animais , Ensaio de Imunoadsorção Enzimática , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Sistemas Automatizados de Assistência Junto ao Leito , Reprodutibilidade dos Testes
8.
Arch Inst Cardiol Mex ; 46(6): 764-9, 1976.
Artigo em Espanhol | MEDLINE | ID: mdl-1023834

RESUMO

For the past few years various authors have reported the antiplatelet action and prolongation of bleeding time with the use of acetyl-salicilic acid. In the present work, we review the frequency of thromboembolism in a group of patients with rheumatic or sclerotic heart disease with atrial fibrillation, in which the treatment with coumarins was suspended and substituted for 1 gram of aspirin P.O. daily. The results were compared with a similar group studied by Cárdenas and col. During the time of the observation 10 patients had 14 thromboembolic accidents, slightly predominated by the emboli in the inferior members and in the cerebral vascular territory. The mortality was 2.5% and in 9 patients hemorrhages of little importance appeared, which could have been caused by the ASA, although it can not be proven. In comparing the results of this work with the above mentioned of Cárdenas, it appeared that the number of thromboemboli, of deaths, and secondary accidents in the group treated with ASA was less than in the group which received coumarin or which were maintained without treatment. Based on the results, it can be concluded that it is possible to substitute the coumarins with acetyl-salicilic acid in the prevention of thromboembolism, in patient with rheumatic or sclerotic heart disease with atrial fibrillation.


Assuntos
Aspirina/uso terapêutico , Fibrilação Atrial/tratamento farmacológico , Tromboembolia/prevenção & controle , Adulto , Doença das Coronárias/prevenção & controle , Cumarínicos/uso terapêutico , Avaliação de Medicamentos , Feminino , Humanos , Pessoa de Meia-Idade
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