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1.
J Appl Toxicol ; 37(6): 758-771, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-27995640

RESUMO

The ability of parabens to promote the appearance of multiple cancer hallmarks in breast epithelium cells provides grounds for regulatory review of the implication of the presence of parabens in human breast tissue. It is well documented that telomere dysfunction plays a significant role in the initiation of genomic instability during carcinogenesis in human breast cancer. In the present study, we evaluated the genotoxic effect of ethyl 4-hydroxybenzoate (ethyl-paraben), with and without metabolic activation (S9), in studies following OECD guidelines. We observed a significant increase in genotoxic damage using the Mouse Lymphoma Assay and in vitro micronucleus (MN) tests in the L5178Y cell line in the presence of S9 only after a short exposure. A high frequency of MN was observed in the TK6 cells after a short exposure (3 h) in the presence of S9 and a long exposure (26 h) without S9. We found significant increases in the MN frequency and induced chromosomal aberrations in the lymphocytes of only one donor after ethyl-paraben exposure in the presence of S9 after a short exposure. Cytogenetic characterization of the paraben-treated cells demonstrated telomere shortening associated with telomere loss and telomere deletions in L5178Y and TK6 cells and lymphocytes of the paraben sensitive-donor. In a control cohort of 68 human lymphocytes, telomere length and telomere aberrations were age-dependent and showed high inter-individual variation. This study is the first to link telomere shortening and the genotoxic effect of ethyl paraben in the presence of S9 and raises the possibility that telomere shortening may be a proxy for underlying inter-individual sensitivity to ethyl-paraben. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Micronúcleos com Defeito Cromossômico/induzido quimicamente , Mutagênicos/toxicidade , Parabenos/toxicidade , Encurtamento do Telômero/efeitos dos fármacos , Ativação Metabólica , Animais , Técnicas de Cultura de Células , Linhagem Celular Tumoral , Humanos , Linfócitos/efeitos dos fármacos , Linfócitos/patologia , Camundongos , Micronúcleos com Defeito Cromossômico/estatística & dados numéricos , Microssomos Hepáticos/metabolismo , Ratos Sprague-Dawley
2.
Radiat Prot Dosimetry ; 164(1-2): 134-7, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25274533

RESUMO

Telomere length has been proposed as a marker of mitotic cell age and as a general index of human organism aging. Telomere shortening in peripheral blood lymphocytes has been linked to cardiovascular-related morbidity and mortality. The authors investigated the potential correlation of conventional risk factors, radiation dose and telomere shortening with the development of coronary artery disease (CAD) following radiation therapy in a large cohort of Hodgkin lymphoma (HL) patients. Multivariate analysis demonstrated that hypertension and telomere length were the only independent risk factors. This is the first study in a large cohort of patients that demonstrates significant telomere shortening in patients treated by radiation therapy who developed cardiovascular disease. Telomere length appears to be an independent prognostic factor that could help determine patients at high risk of developing CAD after exposure in order to implement early detection and prevention.


Assuntos
Doença da Artéria Coronariana/genética , Doença da Artéria Coronariana/mortalidade , Doença de Hodgkin/radioterapia , Radiometria/estatística & dados numéricos , Radioterapia Conformacional/estatística & dados numéricos , Encurtamento do Telômero/fisiologia , Adolescente , Adulto , Idoso , Bioensaio/métodos , Bioensaio/estatística & dados numéricos , Causalidade , Criança , Estudos de Coortes , Comorbidade , Feminino , Doença de Hodgkin/mortalidade , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Prognóstico , Radiometria/métodos , Dosagem Radioterapêutica , Reprodutibilidade dos Testes , Medição de Risco/métodos , Sensibilidade e Especificidade , Taxa de Sobrevida , Encurtamento do Telômero/genética , Adulto Jovem
3.
Appl Opt ; 53(4): 748-55, 2014 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-24514193

RESUMO

We have developed a tomographic diffractive microscope in reflection, which permits observation of sample surfaces with an improved lateral resolution, compared to a conventional holographic microscope. From the same set of data, high-precision measurements can be performed on the shape of the reflective surface by reconstructing the phase of the diffracted field. Doing so allows for several advantages compared to classical holographic interferometric measurements: improvement in lateral resolution, easier phase unwrapping, reduction of the coherent noise, combined with the high-longitudinal precision provided by interferometric phase measurements. We demonstrate these capabilities by imaging various test samples.

4.
Clin Exp Immunol ; 160(2): 199-206, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20030673

RESUMO

The diagnosis of coeliac disease (CD) represents a special challenge in selective immunoglobulin (Ig)A deficiency (IgAD). A high density of T cell receptor (TCR)gammadelta(+) intraepithelial lymphocytes (IELs) and intestinal IgA anti-tissue transglutaminase 2 (anti-TG2) antibody deposits are suggestive of CD. We analysed the density of TCRgammadelta(+) IELs and the deposition of IgM anti-TG2 antibodies in the jejunal mucosa of IgAD patients with and without CD. Immunohistochemical analyses for the number of CD3+ and TCRgammadelta(+) IELs and double immunofluorescence assay for IgM anti-TG2 antibody deposits were performed in biopsies from 25 children with IgAD (nine untreated CD, seven potential CD and nine without CD). Sixteen immunologically intact children without CD represented the controls. IgAD without CD had a higher number of CD3+ and TCRgammadelta(+) IELs than controls (P < 0.05), but lower than IgAD with CD (P < 0.01). No significant differences were noted between IgAD subjects without CD and those with potential CD. Furthermore, IgAD patients without CD showed a higher TCRgammadelta(+)/CD3+ ratio than the control group (P < 0.05), while the ratio was similar to subjects with CD and potential CD. Intestinal IgM anti-TG2 antibody deposits were present in six of seven of the IgAD patients with untreated CD, one of seven with potential CD and none of those without CD. Most of the patients with IgAD show immune activation in the jejunal mucosa. IgM anti-TG2 antibody deposits are present only in CD. Intestinal IgM anti-TG2 and immunohistochemical markers do not discriminate between IgAD and potential CD with IgAD. Therefore, the serum IgG CD-associated autoantibodies remains very important for the diagnosis of CD in IgAD.


Assuntos
Autoanticorpos/análise , Autoantígenos/imunologia , Doença Celíaca/imunologia , Deficiência de IgA/imunologia , Imunoglobulina M/análise , Jejuno/imunologia , Receptores de Antígenos de Linfócitos T gama-delta/análise , Subpopulações de Linfócitos T/patologia , Transglutaminases/imunologia , Autoanticorpos/imunologia , Biópsia , Doença Celíaca/diagnóstico , Doença Celíaca/etiologia , Doença Celíaca/patologia , Criança , Pré-Escolar , Epitélio/imunologia , Epitélio/patologia , Feminino , Proteínas de Ligação ao GTP , Antígenos HLA-DR/análise , Humanos , Deficiência de IgA/complicações , Deficiência de IgA/patologia , Imunoglobulina M/imunologia , Lactente , Mucosa Intestinal/imunologia , Mucosa Intestinal/patologia , Jejuno/patologia , Masculino , Proteína 2 Glutamina gama-Glutamiltransferase , Subpopulações de Linfócitos T/imunologia , Adulto Jovem
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