1,251 research outputs found

    Striatal and extrastriatal atrophy in Huntington's disease and its relationship with length of the CAG repeat

    Get PDF
    Huntington's disease (HD) is an autosomal dominant neurodegenerative disorder that affects the striatum most severely. However, except for juvenile forms, relative preservation of the cerebellum has been reported. The objective of the present study was to perform MRI measurements of caudate, putamen, cerebral, and cerebellar volumes and correlate these findings with the length of the CAG repeat and clinical parameters. We evaluated 50 consecutive patients with HD using MRI volumetric measurements and compared them to normal controls. Age at onset of the disease ranged from 4 to 73 years (mean: 43.1 years). The length of the CAG repeat ranged from 40 to 69 (mean: 47.2 CAG). HD patients presented marked atrophy of the caudate and putamen, as well as reduced cerebellar and cerebral volumes. There was a significant correlation between age at onset of HD and length of the CAG repeat, as well as clinical disability and age at onset. The degree of basal ganglia atrophy correlated with the length of the CAG repeat. There was no correlation between cerebellar or cerebral volume and length of the CAG repeat. However, there was a tendency to a positive correlation between duration of disease and cerebellar atrophy. While there was a negative correlation of length of the CAG repeat with age at disease onset and with striatal degeneration, its influence on extrastriatal atrophy, including the cerebellum, was not clear. Extrastriatal atrophy occurs later in HD and may be related to disease duration.1129113

    Estudo do comportamento mecânico dos compósitos de restauro dentário utilizando técnicas ópticas

    Get PDF
    Os materiais compósitos são hoje em dia cada vez mais utilizados no restauro dentário. Estes materiais substituíram as tradicionais amálgamas que apresentavam alguns inconvenientes. Apesar das vantagens no uso destes novos materiais existem ainda alguns problemas a resolver, nomeadamente a sua contracção durante o processo de cura. Desta forma surgem tensões nos dentes restaurados, podendo originar dano estrutural. Pretende-se com este trabalho estudar o processo de contracção dos compósitos dentários utilizando as técnicas ópticas, holografia digital, ESPI e correlação de imagem que demonstraram estar bem adaptadas a este estudo. É ainda apresentado um estudo comparativo utilizando diferentes materiais compósitos, bem como um estudo numérico com simulação por elementos finitos

    i-Farm: A exploração vitícola inteligente da sociedade da informação e do conhecimento

    Get PDF
    www.i-Farm.pt.Neste trabalho iremos explorar o potencial das mais recentes inovações tecnológicas disponíveis no mercado para construir a i-Farm, a exploração vitícola inteligente da sociedade da informação e do conhecimento. O projecto i-Farm foi financiado pelo Programa DEMTEC da Agência de Inovação, apesar de passível de ser aplicado em qualquer actividade agrícola, é apresentado para o caso concreto da vinha, pois a viticultura foi considerada estratégicas no âmbito do Plano Estratégico Nacional para o Desenvolvimento Rural Português (GPP, 2007), numa lógica de aumento da competitividade do sector agrícola, conforme previsto no Eixo 1 da referida estratégia. A viticultura, mais concretamente a viticultura de precisão, tem vindo a receber uma atenção crescente da comunidade científica e empresarial na medida em que é efectivamente uma actividade capital intensivo em que a realização de investimentos em tecnologias de informação e comunicação podem ser justificados numa análise custo/benefício rigorosa. É hoje possível encontrar na literatura científica e nas empresas de prestação de serviços especializados exemplos concretos da aplicação das mais recentes tecnologias de monitorização remota sem fios na vinha (Camilli et al., 2007, Morais et al., 2008, Neto et al. 2007). Neste projecto quisemos ir mais longe na utilização das tecnologias disponíveis para construir um sistema integrado de apoio à decisão numa abordagem de Business Intelligence e estudar a utilização de digital dashboards para suportar a tomada de decisão ao nível da exploraçãoinfo:eu-repo/semantics/publishedVersio

    Massive lower gastrointestinal bleeding from idiopathic ileocolonic varix: report of a case

    Get PDF
    Dis Colon Rectum. 2006 Apr;49(4):524-6. Massive lower gastrointestinal bleeding from idiopathic ileocolonic varix: report of a case. Lopes LM, Ramada JM, Certo MG, Pereira PR, Soares JM, Ribeiro M, Areias J, Pinho C. SourceGastroenterology Department, Hospital Geral Santo António, Porto, Portugal. [email protected] Abstract Idiopathic varices of the entire colon are very rare. We report on a 64-year-old patient with massive lower gastrointestinal hemorrhage from an extensive ileocolonic varix. Diagnosis was established by colonoscopy. The patient underwent an emergency ileocolectomy with satisfactory results. This rare case shows the importance of colonoscopy in the evaluation of patients with lower gastrointestinal hemorrhage and reminds us that sometimes the diagnosis is not what we expect. Recognition of this abnormality is important because varices may be the cause of massive lower gastrointestinal hemorrhage. PMID: 16395635 [PubMed - indexed for MEDLINE

    Synthesis Of Ag-cofe2o4 Dimer Colloidal Nanoparticles And Enhancement Of Their Magnetic Response

    Get PDF
    This paper reports the structural and magnetic properties of Ag-CoFe 2O4 colloidal dimer nanoparticles (NPs) synthesized using a two-step solution-phase route. Ag NPs were used as seeds to grow Ag-CoFe 2O4 dimer NPs using thermal decomposition of metallic precursor. By means of temperature and field dependent dc magnetization measurements, it is found that the silver due to its interface with CoFe 2O4 particles leads to thermal stabilization of the dimer NPs superior as compared to CoFe2O4 alone. Our results show enhancement of the magnetic anisotropy and a large coercivity at 2 K for dimer NPs, which could be ascribed to interface effect between Ag and CoFe 2O4 components and the related structural defects. © 2011 American Institute of Physics.1097Sun, Y., Xia, Y., Shape-controlled synthesis of gold and silver nanoparticles (2002) Science, 298 (5601), pp. 2176-2179. , DOI 10.1126/science.1077229Wang, C., Wei, Y., Jiang, H., Sun, S., (2009) Nano Lett., 9, p. 4544. , 10.1021/nl903077tLopes, G., Vargas, J.M., Sharma, S.K., Beron, F., Pirota, K.R., Knobel, M., Rettori, C., Zysler, R.D., (2010) J. Phys. Chem. C, 114, p. 10148. , 10.1021/jp102311uHori, H., Yamamoto, Y., Ywamoto, T., Miura, T., Teranishi, T., Miyake, M., (2004) Phys. Rev. B, 69, p. 174411. , 10.1103/PhysRevB.69.174411Jordan, A., Scholz, R., Wust, P., Fahling, H., Felix, R., (1999) J. Magn. Magn. Mater., 201, p. 413. , 10.1016/S0304-8853(99)00088-8Goya, G.F., Grazu, V., Ibarra, M.R., Magnetic nanoparticles for cancer therapy (2008) Current Nanoscience, 4 (1), pp. 1-16. , http://www.ingentaconnect.com/content/ben/cnano/2008/00000004/00000001/ art00001, DOI 10.2174/157341308783591861Yu, H., Chen, M., Rice, P.M., Wang, S.X., White, R.L., Sun, S., Dumbbell-like bifunctional Au-Fe3O4 nanoparticles (2005) Nano Letters, 5 (2), pp. 379-382. , DOI 10.1021/nl047955qPeddis, D., Cannas, C., Piccaluga, G., Agostinelli, E., Fiorani, D., (2010) Nanotechnology, 21, p. 125705. , 10.1088/0957-4484/21/12/125705Desjonquéres, M.C., Barreteau, C., Autés, G., Spanjaard, D., (2007) Phys. Rev. B, 76, p. 024412. , 10.1103/PhysRevB.76.024412Salazar-Alvarez, G., Olsson, R.T., Sort, J., Macedo, W.A.A., Ardisson, J.D., Baro, M.D., Gedde, U.W., Nogues, J., Enhanced coercivity in co-rich near-stoichiometric CoxFe 3-xO4+δ nanoparticles prepared in large batches (2007) Chemistry of Materials, 19 (20), pp. 4957-4963. , DOI 10.1021/cm070827

    A model of the Universe including Dark Energy accounted for by both a Quintessence Field and a (negative) Cosmological Constant

    Full text link
    In this work we present a model of the universe in which dark energy is modelled explicitely with both a dynamical quintessence field and a cosmological constant. Our results confirm the possibility of a future collapsing universe (for a given region of the parameter space), which is necessary for a consistent formulation of string theory and quantum field theory. We have also reproduced the measurements of modulus distance from supernovae with good accuracy.Comment: 11 pages, 4 figures, only the results for the single exponential potential are preserved. One author added. Some changes in the reference section. Submitted to Physical Review

    Adubação mineral de Pinus oocarpa schiede

    Get PDF
    O presente ensaio refere-se à adubação de Pinus oocarpa Schiede. Foi instalado em solo Latossolo Vermelho Escuro Distrófico originalmente sob vegetação de cerrado, no município de Assis, São Paulo. Através de medições periódicos de altura e DAP (diâmetro à altura do peito) das árvores, foram verificados os efeitos da adubação NPK, calagem, S, B e Zn sob delineamento experimental de blocos casualizados com quatro repetições. Pela análise estatística dos últimos dados de altura e diâmetro, quando as plantas estavam com 3 anos, conclui-se que: a adubação NPK proporcionou um aumento significativo no desenvolvimento das plantas em altura e diâmetro; a adubação NPK + calagem aumentou significativamente a altura; a adubação NPK + calagem + S aumentou significativamente o diâmetro e a aplicação de B e Zn não apresentou efeitos significativos.The present work deals with the mineral fertilization of Pinus oocarpa Schiede. The experiment took place in a Distrophic Dark-Red Latosol, formerly under "cerrado" vegetation in Assis, State of São Paulo, Brazil. The height and D.B.C. (diameter breast height) of the trees were periodically measured in order to check the effects of NPK, liming, S, B and Zn fertilization under experimental delineation of randomized blocks with four repetitions . By means of statistical analysis of the last height and diameter data on three year-old plants, we can conclude that: NPK fertilization significantly increased the height and diameter of the plants; NPK + liming treatment significantly increased the plants height; NPK + liming + S treatment significantly increased the plants diameter and the application of B and Zn did not exert any effect

    Unveiling the binding and orientation of the antimicrobial peptide Plantaricin 149 in zwitterionic and negatively charged membranes

    Get PDF
    Antimicrobial peptides are a large group of natural compounds which present promising properties for the pharmaceutical and food industries, such as broad-spectrum activity, potential for use as natural preservatives, and reduced propensity for development of bacterial resistance. Plantaricin 149 (Pln149), isolated from Lactobacillus plantarum NRIC 149, is a peptide with the ability to inhibit bacteria from the Listeria and Staphylococcus genera, which is capable of promoting inhibition and disruption of yeast cells. In this study, the interactions of Pln149 with model membranes composed of zwitterionic and/or anionic phospholipids were investigated using a range of biophysical techniques, including isothermal titration calorimetry, surface tension measurements, synchrotron radiation circular dichroism spectroscopy, oriented circular dichroism spectroscopy, and optical microscopy, in order to elucidate their mode of interactions and provide insight into their functional roles. In anionic model membranes, the binding of Pln149 to lipid bilayers is an endothermic process and induces a helical secondary structure in the peptide. The helices bind parallel to the surfaces of lipid bilayers and can promote vesicle disruption, depending on peptide concentration. Although Pln149 has relatively low affinity for zwitterionic liposomes, it is able to adsorb at their lipid interfaces, disturbing the lipid packing, assuming a similar parallel helix structure with a surface-bound orientation, and promoting an increase in the membrane surface area. Such findings can explain the intriguing inhibitory action of Pln149 in yeast cells whose cell membranes have a significant zwitterionic lipid composition

    Leflunomide/hydroxychloroquine combination therapy targets type I IFN-associated proteins in patients with Sjögren's syndrome that show potential to predict and monitor clinical response

    Get PDF
    OBJECTIVES: To assess to what extent leflunomide (LEF) and hydroxychloroquine (HCQ) therapy in patients with primary Sjögren's syndrome (RepurpSS-I) targets type I IFN-associated responses and to study the potential of several interferon associated RNA-based and protein-based biomarkers to predict and monitor treatment. METHODS: In 21 patients treated with LEF/HCQ and 8 patients treated with placebo, blood was drawn at baseline, 8, 16 and 24 weeks. IFN-signatures based on RNA expression of five IFN-associated genes were quantified in circulating mononuclear cells and in whole blood. MxA protein levels were measured in whole blood, and protein levels of CXCL10 and Galectin-9 were quantified in serum. Differences between responders and non-responders were assessed and receiver operating characteristic analysis was used to determine the capacity of baseline expression and early changes (after 8 weeks of treatment) in biomarkers to predict treatment response at the clinical endpoint. RESULTS: IFN-signatures in peripheral blood mononuclear cell and whole blood decreased after 24 weeks of LEF/HCQ treatment, however, changes in IFN signatures only poorly correlated with changes in disease activity. In contrast to baseline IFN signatures, baseline protein concentrations of galectin-9 and decreases in circulating MxA and Galectin-9 were robustly associated with clinical response. Early changes in serum Galectin-9 best predicted clinical response at 24 weeks (area under the curve 0.90). CONCLUSIONS: LEF/HCQ combination therapy targets type-I IFN-associated proteins that are associated with strongly decreased B cell hyperactivity and disease activity. IFN-associated Galectin-9 is a promising biomarker for treatment prediction and monitoring in pSS patients treated with LEF/HCQ.</p
    corecore