Resumo histórico da actividade arqueológica na Europa Ocidental

Todos os grupos humanos, desde o mais primitivo ao mais evoluído, têm sempre qualquer explicação para o seu passado longínquo. Este facto traduz-se, em especial, no que se diz respeito à tradição, pela transmissão oral ou por via de textos. Há, também, que ter em conta os vestígios materiais deixados pelos nossos antepassados e que são, sem dúvida, testemunhos reais do seu modo de vida. A procura, descoberta e interpretação desses vestígios, é o que ocupa o arqueólogo. A conservação daqueles depende das condições do clima, sendo, como é óbvio, o clima seca o mais propício, da matéria-prima em que foram confeccionados e do tipo de terreno em que se encontram. Estes vestígios são, sem dúvida, um testemunho das actividades dum certo grupo humano.info:eu-repo/semantics/publishedVersio

Vestígios de Praia Calabriana com indústrias da «Pebble Culture» no Alto de Leião : Paço de Arcos

Separata do "Boletim da Sociedade Geológica de Portugal". Vol. 21, Fasc. II-IIINo presente trabalho, noticiam-se vestígios de plataforma de abrasão marinha no Alto de Leião (Paço de Arcos), que pela sua cota (150m), deverá ser considerada como calabriana. À sua superfície dispersam-se pequenos seixos, alguns deles talhados intencionalmente e posteriormente rolados pelo mar, os quais são integráveis no estádio I da «Pebble Culture» marroquina. Do ponto de vista geológico, de acordo com os estudos de alguns autores, podemos considerar a estação agora estudada como contemporânea do segundo ciclo calabriano, já na sua fase regressiva. É pois a mais antiga estação paleolítica dada a conhecer até ao presente em Portugal.Le present travail concerne l'existence de vestiges d'une plate-forme d'abrasion marine a Alto de Leiao (Pac;o de Arcos), qui par sa valeur altimetrique (150 m), peut etre consideree comme calabrienne. Parmi les pauvres caiIIoutis, parsemes a la surface de cette plate-forme, nous avons recueiIIi un assez grand nombre de pieces taillees ulterieurement roulees, dont l'ensemble est comparable au stade I de la « Pebble Culture» du Maroc atlantique. D'apres les recentes etudes de quelques chercheurs, nous considerons cette station paleolitique comme etant contemporaine de la 2 erne phase regressive de la mer calabrienne. C'est done la plus ancienne de toutes les publiees jusqu'a present au Portugal

Contribuição para o conhecimento das indústrias líticas mais antigas do território português: as jazidas com «Pebble Culture» da formação de Belverde - Península de Setúbal (Vilafranquiano médio)

Separata de "Setúbal Arqueológica", Vol. V de 1979As peças talhadas descritas neste trabalho fazem parte de um conglomerado constituído por calhaus rolados de quartzito (70%) e quartzo (30%) tendo sido encontradas à superfície do terreno, quando se procedia ao levantamento cartográfico dessa formação e no seu interior, no decorrer das operações necessárias à análise de imbricação, com vista à determinação das paleocorrentes responsáveis pela sua deposição

Multipactor discharges in parallel-plate dielectric-loaded waveguides including space-charge effects

[EN] The objective of this paper is to study the time evolution of multipactor discharges in a parallel-plate dielectric-loaded waveguide. The electron discharge phenomena investigated in this paper include the effects of space charge, as well as the presence of time varying static fields. In order to perform the simulations presented in this paper, an approach considering simultaneously multiple effective electrons has been used. The results obtained demonstrate that multipactor discharges do turn off by themselves under certain circumstances when they occur in such dielectric-loaded structures.This work was supported by the Spanish Government's Ministerio de Educacion y Ciencia under Project TEC2007-67630-C03-01. The review of this paper was arranged by Editor W. Menninger.Coves, A.; Torregrosa-Penalva, G.; Vicente, C.; Gimeno, B.; Boria Esbert, VE. (2008). Multipactor discharges in parallel-plate dielectric-loaded waveguides including space-charge effects. IEEE Transactions on Electron Devices. 55(9):2505-2511. https://doi.org/10.1109/TED.2008.927945S2505251155

Musashi1 modulates cell proliferation genes in the medulloblastoma cell line Daoy

<p>Abstract</p> <p>Background</p> <p>Musashi1 (Msi1) is an RNA binding protein with a central role during nervous system development and stem cell maintenance. High levels of Msi1 have been reported in several malignancies including brain tumors thereby associating Msi1 and cancer.</p> <p>Methods</p> <p>We used the human medulloblastoma cell line Daoy as model system in this study to knock down the expression of Msi1 and determine the effects upon soft agar growth and neurophere formation. Quantitative RT-PCR was conducted to evaluate the expression of cell proliferation, differentiation and survival genes in Msi1 depleted Daoy cells.</p> <p>Results</p> <p>We observed that <it>MSI1 </it>expression was elevated in Daoy cells cultured as neurospheres compared to those grown as monolayer. These data indicated that Msi1 might be involved in regulating proliferation in cancer cells. Here we show that shRNA mediated Msi1 depletion in Daoy cells notably impaired their ability to form colonies in soft agar and to grow as neurospheres in culture. Moreover, differential expression of a group of Notch, Hedgehog and Wnt pathway related genes including <it>MYCN</it>, <it>FOS</it>, <it>NOTCH2</it>, <it>SMO</it>, <it>CDKN1A</it>, <it>CCND2</it>, <it>CCND1</it>, and <it>DKK1</it>, was also found in the Msi1 knockdown, demonstrating that Msi1 modulated the expression of a subset of cell proliferation, differentiation and survival genes in Daoy.</p> <p>Conclusion</p> <p>Our data suggested that Msi1 may promote cancer cell proliferation and survival as its loss seems to have a detrimental effect in the maintenance of medulloblastoma cancer cells. In this regard, Msi1 might be a positive regulator of tumor progression and a potential target for therapy.</p

Notícia sobre uma lasca-núcleo da Lapa da Rainha, Vimeiro.

89 Jan.-Dez. 1979, p. 265-273

Specific effect of arachidonic acid on 17β-hydroxysteroid dehydrogenase in rat Leydig cells

AbstractIt is well known that arachidonic acid (AA) acts as an intratesticular factor regulating luteinizing hormone-mediated testicular steroidogenesis. The present studies were conducted to determine the effect of AA on steroidogenic enzymes in rat Leydig cells. Exogenously added AA significantly inhibited 22(R)-hydroxy-cholesterol-stimulated testosterone production, which is a clear indication that AA is acting at some point after cholesterol transport to the inner mitochondrial membrane. AA failed to block the conversion of 22(R)-hydroxycholesterol to pregnenolone, indicating that the cytochrome P-450 side-chain cleavage enzyme complex is not the site of inhibition. The present results demonstrate that only 17β-hydroxysteroid dehydrogenase seems to be involved in the AA action, since nearly 60% inhibition of testosterone production was found when the cells were incubated with androstenedione. Furthermore, no effect of AA was found when androstenediol was used as substrate in the testosterone synthesis, which indicates that 3β-hydroxysteroid dehydrogenase is not affected by AA. The conversion of AA to its metabolites is not required for its action on 17β-hydroxysteroid dehydrogenase and the activation of protein kinase C is not involved in the inhibitory effect

Lesão expansiva cerebral devida a citomegalovírus: relato de caso e revisão da literatura

Cytomegalovirus (CMV) disease in acquired immunodeficiency syndrome (AIDS) patients most commonly presents as chorioretinitis and gastro-intestinal infection. Neurological involvement due to CMV may cause several clinical presentations: polyradiculitis, myelitis, encephalitis, ventriculo-encephalitis, and mononeuritis multiplex. Rarely, cerebral mass lesion is described. We report a 39 year-old woman with AIDS and previous cerebral toxoplasmosis. She presented with fever, seizures, and vulval ulcers. Her chest X-ray showed multiple lung nodules, and a large frontal lobe lesion was seen in a brain computed tomography scan. She underwent a brain biopsy through a frontal craniotomy, but her condition deteriorated and she died in the first postoperative day. Histopathological studies and immunohistochemistry disclosed CMV disease, and there was no evidence of cerebral toxoplasmosis, bacterial, mycobacterial or fungal infection. CMV disease should be considered in the differential diagnosis of cerebral mass lesion in AIDS patients. High suspicion index, timely diagnostic procedures (surgical or minimally invasive), and proper utilization of prophylactic and therapeutic medication could improve outcome of these patients.As doenças causadas pelo citomegalovírus (CMV) em pacientes com a síndrome da imunodeficiência adquirida apresentam-se principalmente como corioretinite ou comprometimento gastrointestinal. No sistema nervoso central, o CMV pode causar diversas síndromes clínicas: poliradiculite, mielite, encefalite, ventrículo-encefalite e mononeurite múltipla. Raramente, lesões expansivas cerebrais são descritas. Os autores relatam o caso de uma paciente de 39 anos com antecedentes de infecção pelo HIV e toxoplasmose cerebral, que apresentou-se com febre, convulsões e úlceras vulvares. O raios-X de tórax demonstrou múltiplos nódulos pulmonares e a tomografia computadorizada de crânio evidenciou extensa lesão no lobo frontal esquerdo. Após ser submetida à craniotomia, evoluiu com piora clínica, falecendo no primeiro dia de pós-operatório. Os estudos histopatológicos e imunohistoquímicos demonstraram doença citomegálica. Foram excluídas toxoplasmose cerebral e infecção bacteriana, micobacteriana ou fúngica. Concluímos que, embora seja extremamente raro, o CMV deve ser considerado no diagnóstico diferencial das lesões expansivas cerebrais em pacientes com infecção pelo HIV. Um elevado índice de suspeita, procedimentos diagnósticos oportunos (cirúrgicos ou minimamente invasivos), e o adequado uso de antivirais (terapêuticos e profiláticos) podem melhorar o prognóstico desta letal manifestação

Tuberculous meningitis in HIV-infected patients in Brazil: clinical and laboratory characteristics and factors associated with mortality

Tuberculous meningitis (TBM) is a growing problem in HIV-infected patients in developing countries, where there is scarce data about this co-infection. Our objectives were to analyze the main features and outcomes of HIV-infected patients with TBM. Methods This was a retrospective study of HIV-infected Brazilian patients admitted consecutively for TBM. All patients had Mycobacterium tuberculosis isolated from the cerebrospinal fluid (CSF). Presenting clinical and laboratory features were studied. Multivariate analysis was used to identify variables associated with death during hospitalization and at 9 months after diagnosis. Survival was estimated using the Kaplan–Meier method. Results We included 108 cases (median age 36 years, 72% male). Only 15% had fever, headache, and meningeal signs simultaneously. Forty-eight percent had extrameningeal tuberculosis. The median CD4+ cell count was 65 cells/μl. Among 90 cases, 7% had primary resistance to isoniazid and 9% presented multidrug-resistant strains. The overall mortality during hospitalization was 29% and at 9 months was 41%. Tachycardia and prior highly active antiretroviral therapy (HAART) were associated with 9-month mortality. The 9-month survival rate was 22% (95% confidence interval 12–43%). Conclusions Clinical and laboratory manifestations were unspecific. Disseminated tuberculosis and severe immunosuppression were common. Mortality was high and the 9-month survival rate was low. Tachycardia and prior HAART were associated with death within 9 months of diagnosis147e586e59