Nouvelles observations dans le dépocentre volcano-sédimentaire carbonifère du Massif du Tazekka, Moyen-Atlas, Maroc : implications sur l'évolution géodynamique de la chaîne Hercynienne

A análise integrada das estruturas tectónicas e das fácies do Complexo Vulcano Sedimentar do Maciço de Tazekka sugere que este, à escala da grande bacia carbonífera de ante país da Meseta Oriental marroquina, corresponde a um depocentro ou sub bacia em compressão controlada pela propagação, para NW, de dobras de amortecimento do cavalgamento de Hajra Sbaa el Caid. As sequências tectono sedimentares, detrito conglomeráticas e/ou tufíticas, estão associadas a um magmatismo extrusivo com basaltos, andesitos, dacitos, riodacitos e riólitos homogéneos ou piroclásticos com blocos re sedimentados. Estes vulcanitos correspondem a uma sequência sub alcalina equivalente. As sequências calco alcalinas orogénicas características de ambientes de subducção. Estes resultados, assim como a comparação das idades de contracção regional na Meseta marroquina, permitem integrar o Maciço de Tazekka num contexto de wedge top deepzone dum sistema de bacias de ante país flexural, em compressão comandada pela progressão de duas sequências de cavalgamentos prógrados, de NW, desde o Fameno Tournaisiano ao Viseano sup. Terminal Westfaliano inf., da Meseta Oriental para a Meseta Ocidental, em Marrocos setentrional

Low E-cadherin expression in bladder cancer at the transcriptional and protein level provides prognostic information

We studied E-cadherin down-regulation at the protein level in frozen sections of 111 bladder tumours and 13 normal bladder specimens by means of immunohistochemistry, and at the mRNA level by semi-quantitative RT-PCR in 40 of the same tumours. Results indicate that E-cadherin expression detected by immunohistochemistry correlated with both stage and grade (P< 0.0001 and P< 0.001, respectively). Analysis of recurrence, progression and survival over a mean period of 36 months after surgery in the entire cohort showed that abnormal E-cadherin immunoreactivity correlated strongly with poor outcome (log-rank test: P = 0.001, P = 0.0001 and P = 0.0003, respectively). In multistep logistic regression analysis, only E-cadherin status and stage had significant additional prognostic value (P = 0.008 and OR = 0.2;P = 0.03 and OR = 3.6, respectively). Survival estimates derived from RT-PCR transcript quantification differed significantly for low and high expression (log-rank test: P = 0.0006). These results suggest that the alteration occurs at the transcriptional level and support the clinical and biological relevance of cell adhesion molecules in bladder cancer. © 2000 Cancer Research Campaig

Potencial atrativo de Tithonia diversifolia (Hemsl) A. Gray e Tithonia rotundifolia (Mill) S. F. Blake (Asteraceae) para utilização em controle biológico conservativo.

Objetivou-se identificar o potencial atrativo de Tithonia diversifolia (Hemsl) A. Gray e T. rotundifolia (Mill) S.F. Blake para inimigos naturais, em duas diferentes condições edafoclimáticas do Estado do Rio de Janeiro. O experimento foi conduzido nos campos experimentais da UFRRJ, em Seropédica e da Pesagro-Rio, em Paty do Alferes, entre outubro de 2015 e julho de 2016, com coletas quinzenais de artrópodes. Em Paty do Alferes foram coletados 97 e 486 artrópodes, em Seropédica 195 e 182, em T. diversifolia e T. rotundifolia respectivamente. Foram encontradas 36 famílias de artrópodes em T. diversifolia e 30 em T. rotundifolia; destas, 20 e 13 famílias eram de inimigos naturais, nessa ordem. As famílias com maior frequência para as duas plantas estudas foram Coccinellidae, Dolichopodidae, Carabidae. Entre os fitófagos, destacou-se a presença de Cicadellidae para as duas plantas. Estas culturas tem potencial atrativo, podendo ser utilizada na diversificação de agroecossistemasANAIS CONGRESSO LATINO-AMERICANO DE AGROECOLOGIA, 6.; CONGRESSO BRASILEIRO DE AGROECOLOGIA, 10.; SEMINÁRIO DE AGROECOLOGIA DO DISTRITO FEDERAL E ENTORNO, 5., 2017, Brasília, DF. Agroecologia na transformação dos sistemas agroalimentares na América Latina: memórias, saberes e caminhos para o bem viver: anais. Brasília, DF: Associação Brasileira de Agroecologia, 2017

Uniform cross phase modulation for nonclassical radiation pulses

We propose a scheme to achieve a uniform cross phase modulation (XPM) for two nonclassical light pulses and study its application for quantum non-demolition measurements of the photon number in a pulse and for controlled phase gates in quantum information. We analyze the scheme by quantizing a common phenomenological model for classical XPM. Our analysis first treats the ideal case of equal cross-phase modulation and pure unitary dynamics. This establishes the groundwork for more complicated studies of non-unitary dynamics and difference in phase shifts between the two pulses where decohering effects severely affect the performance of the scheme.Comment: 11 pages, 4 figures. To appear in J. Opt. Soc. Am.

The CHEK2*1100delC mutation has no major contribution in oesophageal carcinogenesis

In response to DNA damage, the cell cycle checkpoint kinase 2 (CHEK2) may phosphorylate p53, Cdc25A and Cdc25C, and regulate BRCA1 function, leading to cell cycle arrest and DNA repair. The truncating germline mutation CHEK2*1100delC abrogates kinase activity and confers low-penetrance susceptibility to breast cancer. We found CHEK2*1100delC in 0.5% of 190 oesophageal squamous cell carcinomas and in 1.5% of 196 oesophageal adenocarcinomas. In addition, we observed the mutation in 3.0% of 99 Barrett's metaplasias and 1.5% of 66 dysplastic Barrett's epithelia, both known precursor lesions of oesophageal adenocarcinoma. Since CHEK2*1100delC mutation frequencies did not significantly differ among oesophageal squamous cell carcinomas, adenocarcinomas and (dysplastic) Barrett's epithelia, as compared to healthy individuals, we conclude that the CHEK2*1100delC mutation has no major contribution in oesophageal carcinogenesis

Frequent loss of the AXIN1 locus but absence of AXIN1 gene mutations in adenocarcinomas of the gastro-oesophageal junction with nuclear β-catenin expression

Up to 60% of gastro-oesophageal junction (GEJ) adenocarcinomas show nuclear β-catenin expression, pointing to activated T-cell factor (TCF)/β-catenin-driven gene transcription. We demonstrate in five human GEJ adenocarcinoma cell lines that nuclear β-catenin expression indeed correlates with enhanced TCF-mediated transcription of a reporter gene. In several tumour types, TCF/β-catenin activation is caused by mutations in either adenomatous polyposis coli (APC), β-catenin exon 3, AXIN1, AXIN2 or β-transducin repeat-containing protein (β-TrCP). In GEJ adenocarcinomas, very few APC and β-catenin mutations have been found. Therefore, the mechanism of Wnt pathway activation remains unclear. In the present study, we did not find AXIN1 gene mutations in 17 GEJ tumours with nuclear β-catenin expression (without β-catenin exon 3 mutations). Six intragenic single nucleotide polymorphisms (SNPs) were identified. One of these, the AXIN1 gene T1942C SNP, has a frequency of 21% but is only very recently described despite numerous AXIN1 gene mutational studies. We provide evidence why this SNP was missed in single strand conformation polymorphism analyses. The AXIN1 gene G2063A variation was previously described as a gene mutation but we demonstrate that this is a polymorphism. With these six SNPs loss of heterozygosity (LOH) was found in 11 of 15 (73%) informative tumours. To investigate a possible AXIN1 gene dosage effect in GEJ tumours expressing nuclear β-catenin, AXIN1 locus LOH was determined in 20 tumours expressing membranous and no nuclear β-catenin. LOH was found in 10 of 13 (77%) informative cases. AXIN1 protein immunohistochemistry revealed cytoplasmic expression in all tumours irrespective of the presence of AXIN1 locus LOH. These data indicate that nuclear β-catenin expression is indicative for activated Wnt signalling and that neither AXIN1 gene mutations nor AXIN1 locus LOH are involved in Wnt pathway activation in GEJ adenocarcinomas