47 research outputs found
Excitatory neurotransmitters in brain regions in interictal migraine patients
<p>Abstract</p> <p>Objective</p> <p>To examine biochemical differences in the anterior cingulate cortex (ACC) and insula during the interictal phase of migraine patients. We hypothesized that there may be differences in levels of excitatory amino acid neurotransmitters and/or their derivatives in migraine group based on their increased sensitivity to pain.</p> <p>Methods</p> <p>2D <it>J</it>-resolved proton magnetic resonance spectroscopy (<sup>1</sup>H-MRS) data were acquired at 4.0 Tesla (T) from the ACC and insula in 10 migraine patients (7 women, 3 men, age 43 ± 11 years) and 8 age gender matched controls (7 women, 3 men, age 41 ± 9 years).</p> <p>Results</p> <p>Standard statistical analyses including analysis of variance (ANOVA) showed no significant metabolite differences between the two subject cohorts in the ACC nor the insula. However, linear discriminant analysis (LDA) introduced a clear separation between subject cohorts based on N-acetyl aspartylglutamate (NAAG) and glutamine (Gln) in the ACC and insula.</p> <p>Conclusion</p> <p>These results are consistent with glutamatergic abnormalities in the ACC and insula in migraine patients during their interictal period compared to healthy controls. An alteration in excitatory amino acid neurotransmitters and their derivatives may be a contributing factor for migraineurs for a decrease in sensitivity for migraine or a consequence of the chronic migraine state. Such findings, if extrapolated to other regions of the brain would offer new opportunities to modulate central system as interictal or preemptive medications in these patients.</p
Hadronic Structure in the Decay and the Sign of the Tau Neutrino Helicity
Based on a sample corresponding to 4.3 million produced tau-pair events, we
have studied hadronic dynamics in the decay tau- --> nu_tau pi- pi0 pi0 in data
recorded by the CLEO II detector operating at the CESR e+e- collider. The decay
is dominated by the process tau --> nu_tau a_1(1260), with the a_1 meson
decaying to three pions predominantly via the lowest dimensional (mainly
S-wave) a_1 --> rho pi Born amplitude. From fits to the Dalitz plot and angular
observables, we find significant additional contributions from amplitudes for
a_1 decay to sigma pi, f_0(1370) pi and f_2(1270) pi, as well as higher
dimensional a_1 --> rho pi and rho' pi amplitudes. The squared sigma pi
amplitude accounts for ~15% of the total tau- --> nu_tau pi- pi0 pi0 rate in
the models considered. We have searched for additional contributions from tau
--> nu_tau pi'(1300). We place 90% confidence level upper limits on the
branching fraction for this channel of between 1.0*10^{-4} and 1.9*10^{-4},
depending on the pi' decay mode. The pi- pi0 pi0 mass spectrum is parametrized
by a Breit-Wigner form with a mass-dependent width which is specified according
to the results of the Dalitz plot fits plus a coupling to an a_1 --> K* K
amplitude. From a chi^2 fit, we extract the pole mass and width of the a_1, as
well as the magnitude of the K* K coupling. We have also investigated the
impact of a possible contribution from the a_1'(1700) meson on this spectrum.
Finally, exploiting the parity-violating angular asymmetry in a_1 --> 3pi
decay, we determine the signed value of the tau neutrino helicity to be
h_{\nu_\tau} = -1.02 +- 0.13(stat.) +- 0.03(syst.+model), confirming the
left-handedness of the tau neutrino.Comment: 44 pages, postscript file also available through
http://w4.lns.cornell.edu/public/CLN
Diagnosis, pathophysiology and management of chronic migraine: a proposal of the Belgian Headache Society
Quais as principais caracterÃsticas organizacionais das empresas dos diferentes segmentos da construção civil?
Resumo Neste artigo os autores se propõem a identificar os fatores que definem as principais caracterÃsticas organizacionais de empresas do subsetor da construção civil, localizadas em Curitiba e região metropolitana, assim como verificar as diferenças existentes entre os cinco segmentos de atividade mais relevantes desse mercado: residencial, industrial e comercial, infraestrutura, serviços especializados e construção industrializada. Para tanto, foi desenvolvida uma pesquisa exploratória e de natureza quantitativa, em nÃvel de mestrado. O método survey foi escolhido como procedimento principal para este estudo, permitindo a obtenção de dados primários por meio da aplicação de um questionário em um grupo de 118 empresas. Esse questionário procurou identificar o perfil da organização e as caracterÃsticas organizacionais das empresas avaliadas. Os dados foram analisados com a aplicação de técnicas multivariadas de análise fatorial e análise discriminante. A análise fatorial evidenciou as estratégias de melhoria, o comportamento do indivÃduo no trabalho, a estrutura de funcionamento, a dinâmica de crescimento, o estilo de gestão, as relações interpessoais e o posicionamento da empresa perante o mercado como fatores determinantes. A análise discriminante apontou significativa homogeneidade no desenvolvimento organizacional das empresas que representam os diferentes segmentos de atividade
Modeling and measurements of heat transfer phenomena in two-phase PbSn alloy solidification in an external magnetic field
Purification and properties of the fatty acids synthetase complex from Neurospora crassa, and the nature of the fas-mutation
Two-Dimensional Proton Magnetic Resonance Spectroscopy versus J-Editing for GABA Quantification in Human Brain: Insights from a GABA-Aminotransferase Inhibitor Study
Resistência a antimicrobianos de bactérias oriundas de ambiente de criação e filés de tilápias do nilo (Oreochromis niloticus) Antibacterial resistance in bacteria from fish pond and Nile tilapia fillets (Oreochromis niloticus)
A resistência de bactérias a antimicrobianos foi determinada em uma piscicultura de tilápias (Oreochromis niloticus) em tanques de terra, sem utilização de antibióticos para profilaxia ou controle de doenças. Foi selecionado um tanque, capturados peixes e coletadas amostras de conteúdo intestinal e superfÃcie dos peixes, água de abastecimento e do tanque, ração, filés de tilápias frescos e congelados. Colônias representativas foram selecionadas e analisadas pelos testes de Gram, catalase, oxidase e oxidaçãofermentação. Foram selecionadas 89 amostras e submetidas a antibiograma, utilizando vários antimicrobianos. A maioria das bactérias pertenceu à s famÃlias Enterobacteriaceae e Vibrionaceae. Tanto no ambiente de criação como nos filés de tilápias observou-se que os isolados bacterianos apresentaramse resistentes principalmente a ampicilina e eritromicina. O Ãndice de múltipla resistência a antimicrobianos (MAR) foi calculado, sendo que do total de 89 isolados analisados 74 (83%), apresentaram MAR ³ 0,2, ou seja apresentaram-se resistentes a dois ou mais antimicrobianos. As freqüências de Ãndice MAR foram altas e maiores na ração.<br>This study was conducted in a freshwater tilapia farm that has not used any antibiotic. It was selected one pond, caught 15 fishes and collected samples of intestinal content and mucus surface, water influent and pond water, ration, fresh tilapia fillets and frozen fillets.. Phenotypical characteristics, Gram stain, oxidase production, oxidative-fermentative utilization of glucose (O-F) were determined of representative colony. Were selected 89 strains and submitted for antimicrobial sensitivy test using several antibiotics. The major identified bacterial families were belonged Enterobacteriaceae and Vibrionaceae. The most isolates showed resistance to ampicilin and eritromicin. From the 89 isolates evaluated 74 (83%) showed a multiple antibiotic resistance index (MAR) ³ 0.2, that mean resistance to two or more antibiotics. The MAR Ãndice frequency were higher and bigger in the rations