Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 15 de 15
Filtrar
1.
Rev Sci Instrum ; 87(11): 115116, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27910557

RESUMO

A new experiment is described to detect a permanent electric dipole moment of the proton with a sensitivity of 10-29 e ⋅ cm by using polarized "magic" momentum 0.7 GeV/c protons in an all-electric storage ring. Systematic errors relevant to the experiment are discussed and techniques to address them are presented. The measurement is sensitive to new physics beyond the standard model at the scale of 3000 TeV.

2.
Phys Rev Lett ; 112(9): 091302, 2014 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-24655238

RESUMO

The CERN Axion Solar Telescope has finished its search for solar axions with (3)He buffer gas, covering the search range 0.64 eV ≲ ma ≲ 1.17 eV. This closes the gap to the cosmological hot dark matter limit and actually overlaps with it. From the absence of excess x rays when the magnet was pointing to the Sun we set a typical upper limit on the axion-photon coupling of gaγ ≲ 3.3 × 10(-10) GeV(-1) at 95% C.L., with the exact value depending on the pressure setting. Future direct solar axion searches will focus on increasing the sensitivity to smaller values of gaγ, for example by the currently discussed next generation helioscope International AXion Observatory.

3.
J Periodontal Res ; 47(4): 532-42, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22472034

RESUMO

BACKGROUND AND OBJECTIVE: Nonsurgical periodontal treatment controls periodontal inflammation. Matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs) are implicated both in the destruction and in the healing of periodontal tissues. The aim of the present study was to compare the mRNA expression of MMP-1, -3, -8, -9 and -13 and TIMP-1 in chronic periodontitis before and after initial periodontal treatment. MATERIAL AND METHODS: Ninety gingival samples were harvested from 30 patients with chronic periodontitis (15 nonsmokers and 15 smokers) before and after nonsurgical treatment and from 30 periodontally healthy control subjects (15 nonsmokers and 15 smokers). Clinical parameters were assessed before and after treatment. Total RNA was isolated, and mRNA expression of MMPs and TIMP-1 was assessed by RT-PCR. RESULTS: Periodontal treatment significantly increased TIMP-1 expression and decreased the ratios of MMPs/TIMP-1. Post-treatment, nonsmokers with periodontitis had significantly higher MMP-8 and TIMP-1 expression than healthy nonsmokers, and smokers with periodontitis had significantly higher MMP-13 and TIMP-1 expressions than healthy smokers. Post-treatment, smokers had significantly higher TIMP-1 expression and lower MMP-8/TIMP-1 ratio than nonsmokers. Post-treatment, there was no correlation among MMPs, and the expression of MMPs and TIMP-1 was not correlated with clinical measurements. CONCLUSION: Periodontal treatment increased TIMP-1 expression and decreased the ratios of MMPs/TIMP-1 in chronic periodontitis. The post-treatment increase in TIMP-1 expression was higher for smokers. The TIMP-1 expression was higher post-treatment than in health. Post-treatment, MMP-8 expression was higher in nonsmokers with periodontitis than in healthy nonsmokers, whereas MMP-13 expression was higher in smokers with periodontitis than in healthy smokers.


Assuntos
Periodontite Crônica/enzimologia , Periodontite Crônica/terapia , Metaloproteinases da Matriz/biossíntese , Fumar/metabolismo , Inibidor Tecidual de Metaloproteinase-1/biossíntese , Adulto , Estudos de Casos e Controles , Distribuição de Qui-Quadrado , Raspagem Dentária , Feminino , Gengiva/enzimologia , Humanos , Masculino , Pessoa de Meia-Idade , Índice Periodontal , RNA Mensageiro/biossíntese , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Estatísticas não Paramétricas
4.
J Periodontal Res ; 46(5): 576-83, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21732946

RESUMO

BACKGROUND AND OBJECTIVE: Matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs) are important for extracellular matrix. Expression of MMPs has been evaluated in gingiva without studying smoking. The aim of this study was to explore the effect of smoking on mRNA expression of MMP-1, -3, -8, -9 and -13 and TIMP-1 in untreated chronic periodontitis and in periodontal health. MATERIAL AND METHODS: Gingival samples were harvested from 30 subjects with untreated chronic periodontitis (15 nonsmokers and 15 smokers) and 30 periodontally healthy subjects (15 nonsmokers and 15 smokers). Full-mouth plaque score, gingival index, bleeding on probing, probing depth and clinical attachment level were recorded. Total RNA was isolated, and the mRNA expression of MMPs and TIMP-1 was assessed by RT-PCR. RESULTS: Periodontitis groups were comparable in clinical measurements. Nonsmoker subjects with periodontitis had statistically significantly higher MMP-1, lower MMP-9 and TIMP-1 expression and higher MMP-1/TIMP-1 ratio than smokers; and higher MMP-8 expression and MMP-8/TIMP-1 and MMP-1/TIMP-1 ratios than healthy nonsmokers. Healthy nonsmokers had statistically significantly higher MMP-13 expression than healthy smokers. Smoker periodontitis and healthy subjects had similar expression levels of MMPs and TIMP-1 and MMPs/TIMP-1 ratios. There was correlation among the MMPs only for smoker periodontitis subjects. Expression of MMP-13 was correlated with mean clinical attachment level. CONCLUSION: Within its limits, this study demonstrated that smoking affected mRNA expression of MMPs and TIMP-1, MMPs/TIMP-1 ratios and relationships among MMPs in untreated chronic periodontitis and expression of MMPs in health. In the absence of smoking, chronic periodontitis affected expression of MMPs and MMPs/TIMP-1 ratios.


Assuntos
Periodontite Crônica/enzimologia , Metaloproteinases da Matriz/biossíntese , Fumar/efeitos adversos , Inibidor Tecidual de Metaloproteinase-1/biossíntese , Adulto , Idoso , Estudos de Casos e Controles , Estudos Transversais , Feminino , Humanos , Masculino , Inibidores de Metaloproteinases de Matriz , Metaloproteinases da Matriz/genética , Pessoa de Meia-Idade , RNA Mensageiro/biossíntese , Estatísticas não Paramétricas , Inibidor Tecidual de Metaloproteinase-1/genética
5.
Phys Rev Lett ; 107(26): 261302, 2011 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-22243149

RESUMO

The CERN Axion Solar Telescope (CAST) has extended its search for solar axions by using (3)He as a buffer gas. At T=1.8 K this allows for larger pressure settings and hence sensitivity to higher axion masses than our previous measurements with (4)He. With about 1 h of data taking at each of 252 different pressure settings we have scanned the axion mass range 0.39 eV≲m(a)≲0.64 eV. From the absence of excess x rays when the magnet was pointing to the Sun we set a typical upper limit on the axion-photon coupling of g(aγ)≲2.3×10(-10) GeV(-1) at 95% C.L., the exact value depending on the pressure setting. Kim-Shifman-Vainshtein-Zakharov axions are excluded at the upper end of our mass range, the first time ever for any solar axion search. In the future we will extend our search to m(a)≲1.15 eV, comfortably overlapping with cosmological hot dark matter bounds.

6.
Exp Mol Pathol ; 80(2): 177-82, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16259977

RESUMO

Tenascin-C (Tn-C) is a matricellular protein involved in the initial and intermediate stages of cell adhesion. The present study is the first undertaken to comparatively investigate Tn-C in neoplastic, non-neoplastic thyroid lesions and normal thyroid tissues. Forty-eight thyroid specimens were studied immunohistochemically using a monoclonal antibody against Tn-C. Immunohistochemistry was supplemented by RT-PCR analysis of the two Tn-C mRNA splice variants in 13 thyroid cancer cell lines. Normal and non-neoplastic tissues were devoid of Tn-C, as well as follicular neoplasms, Huerthle-cell and anaplastic carcinomas. Most papillary carcinomas showed a focally intensive extracellular staining, localized in the connective tissue stroma, whereas most medullary carcinomas showed a staining in the connective tissue but also in intracellular location mainly. RT-PCR analysis detected Tn-C mRNA in all thyroid cancer cell lines with prevalence of the large splice variant in all but the medullary line, characterized by a higher Tn-Csmall:Tn-Clarge ratio. In conclusion, Tn-C re-expression has been observed in papillary and medullary thyroid carcinomas with different staining patterns accompanied by the prevalence of different mRNA splice variants in cell cultures. It seems possible that Tn-C is rather synthesized by tumor cells than by activated stromal cells.


Assuntos
Processamento Alternativo/genética , Regulação Neoplásica da Expressão Gênica , Tenascina/genética , Tenascina/metabolismo , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/metabolismo , Adolescente , Adulto , Idoso , Estudos de Casos e Controles , Linhagem Celular Tumoral , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Tenascina/biossíntese , Neoplasias da Glândula Tireoide/patologia
7.
Phys Rev Lett ; 94(12): 121301, 2005 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-15903903

RESUMO

Hypothetical axionlike particles with a two-photon interaction would be produced in the sun by the Primakoff process. In a laboratory magnetic field ("axion helioscope"), they would be transformed into x-rays with energies of a few keV. Using a decommissioned Large Hadron Collider test magnet, the CERN Axion Solar Telescope ran for about 6 months during 2003. The first results from the analysis of these data are presented here. No signal above background was observed, implying an upper limit to the axion-photon coupling g(agamma)<1.16x10(-10) GeV-1 at 95% C.L. for m(a) less, similar 0.02 eV. This limit, assumption-free, is comparable to the limit from stellar energy-loss arguments and considerably more restrictive than any previous experiment over a broad range of axion masses.

8.
J Exp Clin Cancer Res ; 22(1): 99-105, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12725329

RESUMO

The aim of the present study was to assess the use of an alternative molecular approach for p53 mutation detection and to investigate the usefulness of p53 as a prognostic indicator in bladder cancer. We applied the NIRCA assay, which consists of two-step PCR amplification, transcription of the amplified sequence, hybridisation of the transcripts and treatment with RNAses which recognizes mismatches due to the presence of mutations. Results of molecular analysis are correlated with immunohistochemical findings, standard clinopathological parameters and survival. p53 mutations were detected in 42.4% of the 66 examined TCCs cases. We could not demonstrate any statistical relationship between the presence of p53 mutation and p53 protein overexpression, and tumor stage or grade. A trend towards higher mutation rate in higher grade tumours was observed, although this failed to reach statistical significance. Despite the observation that the alterations of p53 gene are associated features of aggressive phenotype of transitional cell carcinomas they do not seem to offer additional prognostic information.


Assuntos
Genes p53 , Mutação , Neoplasias da Bexiga Urinária/genética , Carcinoma de Células de Transição/genética , Carcinoma de Células de Transição/mortalidade , Carcinoma de Células de Transição/patologia , Estudos de Coortes , DNA de Neoplasias/genética , Intervalo Livre de Doença , Éxons/genética , Seguimentos , Grécia , Humanos , Imuno-Histoquímica/métodos , Análise Multivariada , Análise de Sobrevida , Fatores de Tempo , Neoplasias da Bexiga Urinária/mortalidade , Neoplasias da Bexiga Urinária/patologia , População Branca/genética
9.
Cardiovasc Pathol ; 9(3): 181-3, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10989318

RESUMO

Several studies suggest that certain viral and bacterial pathogens may contribute to the process of atherogenesis. However, this relation between infectious agents and atherosclerosis has not yet been established with certainty. The aim of this study was to investigate the presence of CMV in carotid endarterectomies from 40 patients suffering from atherosclerosis using immunohistochemistry and the polymerase chain reaction (PCR). None of the specimens examined gave a positive result, indicating absence of CMV particles or CMV DNA sequences in the walls of carotid arteries. This finding suggests it is possible that CMV infection may not play a major role in the formation of atheroma. Therefore, further investigation is required in order to clarify the etiology of atherosclerosis.


Assuntos
Arteriosclerose/virologia , Doenças das Artérias Carótidas/virologia , Infecções por Citomegalovirus/virologia , Citomegalovirus/isolamento & purificação , Idoso , Antígenos Virais/análise , Arteriosclerose/patologia , Doenças das Artérias Carótidas/patologia , Citomegalovirus/genética , Citomegalovirus/imunologia , DNA Viral/análise , Endarterectomia das Carótidas , Feminino , Humanos , Imuno-Histoquímica , Masculino , Reação em Cadeia da Polimerase
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...