RESUMO
Idiopathic normal pressure hydrocephalus (INPH) is a syndrome that can be characterised by the following triad of symptoms: gait disturbances, cognitive impairment and urinary incontinence. The suspected diagnosis can be confirmed by cerebral ventriculomegaly and by a positive result of cerebrospinal fluid drainage. The frequent occurrence of comorbidity and a unflinching firm belief in the significance of the triad of clinical symptoms can hinder a correct diagnosis, leading to a delay in treatment and a poor prognosis. To illustrate this thesis we describe a 77-year-old patient with INPH and severe neuropsychiatric comorbidity.
Assuntos
Hidrocefalia de Pressão Normal/diagnóstico , Transtornos Mentais/diagnóstico , Idoso , Comorbidade , Diagnóstico Diferencial , Feminino , Humanos , Hidrocefalia de Pressão Normal/epidemiologia , Transtornos Mentais/epidemiologia , PrognósticoRESUMO
This paper presents in situ observations of the epitaxial nucleation and growth of the stable polymorph of a steroid, 7alphaMna, on a specific face of the metastable form at low supersaturation, using optical microscopy and in situ Raman spectroscopy. The presence of the metastable polymorph is essential for the nucleation and growth of the stable one. The order of the metastable zones of the stable and metastable polymorphs is reversed for the epitaxial growth process as compared to the case of 3D nucleation. The rate of transformation of the metastable polymorph to the stable one can be controlled by the supersaturation.
Assuntos
Modelos Moleculares , Pregnenos/química , Acetona/química , Cristalização , Etanol/química , Cinética , Microscopia Eletrônica de Varredura , Estrutura Molecular , Solubilidade , Solventes/química , Análise Espectral Raman , Tecnologia Farmacêutica , TemperaturaRESUMO
The characteristics of the anion-sensitive Mg2+-ATPase activity of the rabbit erythrocyte have been studied in a lyophilized ghost preparation. The enzyme appears to be different from the anion-sensitive Mg2+-ATPase activity of other tissues in many parameters, such as optimal pH, effects of various anions, oligomycin sensitivity and effects of Triton X-100. The enzyme is insensitive towards inhibition by irreversibly bound 4,4'-diisothiocyano-dihydrostilbene-2,2'-disulfonic acid (H2DIDS). This excludes a relationship between the enzyme and the "band 3" protein, which is thought to be involved in the anion exchange over the erythrocyte membrane. From the effects of ethyleneglycol-bis-(beta-aminoethylether)-N,N'-tetraacetic acid (EGTA), CaCl2, chlorpromazine and ruthenium red it is concluded that the enzyme activity does not represent a separate entity but is part of the (Ca2+ + Mg2+)-ATPase system of the erythrocyte membrane. A reported stimulatory effect of carbonic anhydrase is attributed to a contamination of the carbonic anhydrase preparation by calcium and/or (Ca2+ + Mg2+)-ATPase activator protein.
Assuntos
Adenosina Trifosfatases/metabolismo , Membrana Eritrocítica/enzimologia , Eritrócitos/enzimologia , Benzenossulfonatos/farmacologia , Bicarbonatos/farmacologia , Calcimicina/farmacologia , Cálcio/metabolismo , Cloreto de Cálcio/farmacologia , Anidrases Carbônicas/farmacologia , Magnésio/farmacologia , Oligomicinas/farmacologia , Ouabaína/farmacologia , Polietilenoglicóis/farmacologia , Estilbenos/farmacologia , Tiocianatos/farmacologiaRESUMO
The polymorphism of the CNS active compound Org 13011 was studied using different crystallisation methods (i.e. different solvents and cooling rates). The samples were analysed by Raman, solid state NMR, X-ray powder diffraction (XRPD) and thermal analysis. This led to the characterisation of two crystalline forms A and B. Further high temperature analysis using Raman, XRPD, solid state NMR and DSC revealed another two (high temperature) crystalline forms C and D. The transitions to the high temperature crystalline forms occur at temperatures of about 60 degrees C. This study shows that the application of high temperature experiments is useful and can lead to the discovery of new crystalline forms.
Assuntos
Fármacos do Sistema Nervoso Central/química , Piperazinas/química , Pirróis/química , Cristalização , Análise Diferencial Térmica , Temperatura Alta , Isomerismo , Espectroscopia de Ressonância Magnética , Análise Espectral Raman , Temperatura , Difração de Raios XRESUMO
The accumulation kinetics of polycyclic aromatic hydrocarbons (PAHs) by the freshwater oligochaete Lumbriculus variegatus were measured for field-contaminated and laboratory-dosed sediment. In addition, sediment manipulations typically used for homogenization and dosing in bioaccumulation assays were compared. Rather than an asymptotic approach to steady state, both resident and dosed PAH accumulation exhibited a peak during the 14-d assays, with steeper declines being noted for the lower-molecular-weight compounds. Lack of evidence of a peak for higher-molecular-weight PAHs may be due to slower kinetics and the short length of the assay. Relative to minimally mixed sediment, slurried sediment enhanced the accumulation of less-soluble resident PAHs, did not affect moderately soluble PAHs, and reduced the uptake of the more-soluble PAHs, fluorene and phenanthrene. Aging sediment after mixing reduced the availability of highly to moderately soluble resident PAHs but had no effect on less-soluble PAHs. A similar effect was noted for dosed PAHs, though a larger reduction in bioavailability was observed. Dosed PAH uptake clearance coefficients (ks) exceeded those of minimally mixed resident PAHs by factors of 3 to 4 for pyrene and 26 for benzo[a]pyrene. These results demonstrate that sediment manipulations and contamination history need to be considered when measuring PAH bioaccumulation.
Assuntos
Sedimentos Geológicos/química , Oligoquetos/fisiologia , Hidrocarbonetos Policíclicos Aromáticos/farmacocinética , Poluentes do Solo/farmacocinética , Animais , Cinética , Solubilidade , Distribuição TecidualRESUMO
EF-Tu is often referred to as a model for guanine-nucleotide-binding regulatory proteins (G-proteins), since X-ray diffraction analysis of its GTP-binding domain shows a detailed location of the 'consensus' amino acid sequences involved in nucleotide binding. Fluoroaluminates are thought to mimick the gamma-phosphate in the GTPase centre on account of their activating effect on a variety of GTP binding proteins. In the case of EF-Tu, we could find no such effects on the basis of at least three independent functional assays. We did notice, however, complicating interactions between free nucleotides, fluoroaluminates and other ligands. By consequence, if indeed AlF4- behaves as a gamma-phosphate analogue in G-proteins, then EF-Tu must have a different GDP/GTP binding site, despite of the conserved consensus sequences.
Assuntos
Compostos de Alumínio , Alumínio/farmacologia , Cloretos/farmacologia , Guanosina Difosfato/metabolismo , Guanosina Trifosfato/metabolismo , Fator Tu de Elongação de Peptídeos/metabolismo , Fluoreto de Sódio/farmacologia , Cloreto de Alumínio , Antibacterianos/farmacologia , Sítios de Ligação , Escherichia coli/metabolismo , Cinética , Conformação Proteica , Piridonas/farmacologia , Ribossomos/metabolismo , Vanadatos/farmacologia , Difração de Raios XRESUMO
The charge state distributions of Fe, Na, and F are determined in a photoionized laboratory plasma using high resolution x-ray spectroscopy. Independent measurements of the density and radiation flux indicate unprecedented values for the ionization parameter xi=20-25 erg cm s(-1) under near steady-state conditions. Line opacities are well fitted by a curve-of-growth analysis which includes the effects of velocity gradients in a one-dimensional expanding plasma. First comparisons of the measured charge state distributions with x-ray photoionization models show reasonable agreement.