4,158 research outputs found
Hipersonolência Diurna. Narcolepsia, Qual a Etiologia?
Introdução: A narcolepsia é uma doença do sono REM com desregulação do ciclo de
sono-vigília, consequente sonolência diurna e eventual associação a alucinações
hipnagógicas, paralisia do sono e cataplexia. A sua prevalência é de 0,05 a 0,02% no adulto mas desconhecida na idade pediátrica.
Caso clínico: Criança de seis anos, previamente saudável com sonolência excessiva até 18 horas/dia e discinésia oromandibular, desequilíbrio na marcha e movimentos coreiformes dos membros superiores. Duas semanas antes realizara vacinação para a gripe pandémica. Registou-se ainda hiperfagia diurna e nocturna durante cinco dias com resolução espontânea, episódios de cataplexia perante riso e alterações emocionais e tremor da cabeça e dos membros superiores com melhoria clínica progressiva após oito dias.
Realizou RMN-CE e EEG sem alterações. O exame líquido céfalo-raquidiano e PCR
para painel de vírus herpes, Mycoplasma pneumoniae e enterovírus negativas. Nesta
fase realizou polissonografia com teste de latências múltiplas do sono (TLMS) sem
alterações.
Exame cultural do exsudado faríngeo, TASO e anticorpo AntiDnase B negativos. Da
exaustiva investigação que realizou apresentava serologias ELISA e WB compatíveis
com infecção por Borrelia burdorferi, pelo que cumpriu ceftriaxone 14 dias. Serologias
para influenza A mostraram IgM 39 UA/mL com IgG 194 UA/mL com segunda amostra com IgM 43 UA/mL e IgG 162 UA/mL (VR IgM<20;IgG<20).
O estudo da autoimunidade revelou ANA 1/320, anticorpos anticardiolipina e antinucleares
extraíveis negativos. Restantes autoanticorpos e doseamento de complemento
normal. Anticorpos Anti-NMDA e VKCG negativos. Doseamento de hipocretina muito
diminuído com HLA DR2 e DQB1*0602 presentes.
A polissonografia com TLMS, sete meses após a primeira, confirmou sonolência excessiva com quatro inícios do sono REM sugestivos de narcolepsia.
Faz terapêutica com metilfenidato, a sonolência diurna diminuiu e cumpre o seu horário escolar sem limitações.
Comentários: O diagnóstico de narcolepsia foi sugerido pela clínica e confirmado pelo
teste de latências múltiplas. O valor de hipocretina diminuído pode sugerir uma
etiologia autoimune. Uma infecção como a borreliose ou a vacinação prévia para H1N1,
responsabilizada por outros casos de narcolepsia podem ter sido desencadeantes de uma alteração imunitária responsável pela doença, nesta criança com a susceptibilidade HLA DR2 e DBQ1*0602
Infliximab in Recalcitrant Generalized Pustular Arthropatic Psoriasis
Generalized pustular psoriasis is an unstable inflammatory type of psoriasis, with widespread areas of erythema and sterile pustules, associated with fever and systemic symptoms. Infliximab is a monoclonal antibody with anti-TNFalpha activity, approved for use in psoriasis. We describe a male patient with a long history of stable arthropathic psoriasis, hospitalized with a generalized pustular psoriasis and acute exacerbation of articular complaints. The disease was resistant to multiple therapies (acitretin, methotrexate and corticosteroids), so the patient was started on infliximab, with a very rapid response of both cutaneous and articular symptoms. He had complete clearing of lesions at week 12, and marked improvement of the articular symptoms. No recurrence occurred at 8 months of follow-up with infliximab every 8 weeks. Infliximab had an extremely rapid therapeutic action response on a recalcitrant generalized pustular psoriasis. The articular response was also excellent, with significant improvement of quality of life
The moisture effect on 223Ra and 224Ra measurements using Mn-cartridges
Important processes in the ocean can be evaluated with radioactive nuclides, including radium isotopes. An approach for quantifying radium isotopes in seawater with in-situ pumps has been developed in advance of the GEOTRACES program [1]. Precise measurements of 223Ra and 224Ra by means of the delayed coincidence counting system (RaDeCC) [2] are dependent on the moisture content of the medium [3]. In order to verify the optimum moisture content for this new approach, a set of measurements of the Mn-cartridge standards under different moisture conditions was conducted, as this was done previously for acrylic fiber. At a time, an amount of water equivalent to 5% of the cartridges weight was added, and the activities were determined.
The variation of 224Ra activity occurs mainly between 0 to 15% of humidity. Under moisture conditions higher than 15%, the emanation efficiency reaches an optimum plateau until 100% of moisture. This result differs slightly from those found for 224Ra measurements using the acrylic fiber (plateau from 30 to 100 %) [3].
The 223Ra Mn-cartridge standard reaches the plateau under 5% of humidity, and above 50% moisture the activity seems to decrease. Considering the counting error (7%), it is hard to state that the effect of the moisture is critical. However, this decrease can be related to the shorter half-life of the 219Rn compared to the time needed to its diffusion through the water film, which could be a reason for the frequently observed lower efficiency of the 223Ra channel of the RaDeCC system [4].
[1] Henderson et al. (2013) J. Radioanal. Nucl. Chem. 296, 357–362. [2] Moore and Arnold (1996) J. Geophys. Res. 101, 321–1329. [3] Sun and Torgersen (1998) Mar. Chem. 61, 163–171. [4] Charette et al. (2012) Limnol. Oceanogr. 10, 451–463
Photoassociative ionization of Na inside a storage ring
Motivated by recent interest in low dimensional arrays of atoms, we
experimentally investigated the way cold collisional processes are affected by
the geometry of the considered atomic sample. More specifically, we studied the
case of photoassociative ionization (PAI) both in a storage ring where
collision is more unidirectional in character and in a trap with clear
undefinition of collision axis. First, creating a ring shaped trap (atomotron)
we investigated two-color PAI dependence with intensity and polarization of a
probing laser. The intensity dependence of the PAI rate was also measured in a
magneto-optical trap presenting equivalent temperature and density conditions.
Indeed, the results show that in the ring trap, the value of the PAI rate
constant is much lower and does not show evidences of saturation, unlike in the
case of the 3D-MOT. Cold atomic collisions in storage ring may represent new
possibilities for study.Comment: 5 pages, 5 figures; Accepted by Optics Communicatio
A Capacidade de rebrota das castanheiras.
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