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2.
J Neurol ; 268(8): 2780-2807, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32318851

RESUMO

Despite intensive investigations, about 30% of stroke cases remains of undetermined origin. After exclusion of common causes of stroke, there is a number of rare heritable and non-heritable conditions, which often remain misdiagnosed, that should be additionally considered in the diagnosis of cryptogenic stroke. The identification of these diseases requires a complex work up including detailed clinical evaluation for the detection of systemic symptoms and signs, an adequate neuroimaging assessment and a careful family history collection. The task becomes more complicated by phenotype heterogeneity since stroke could be the primary or unique manifestation of a syndrome or represent just a manifestation (sometimes minor) of a multisystem disorder. The aim of this review paper is to provide clinicians with an update on clinical and neuroradiological features and a set of practical suggestions for the diagnostic work up and management of these uncommon causes of stroke. The identification of these stroke causes is important to avoid inappropriate and expensive diagnostic tests, to establish appropriate management measures, including presymptomatic testing, genetic counseling, and, if available, therapy. Therefore, physicians should become familiar with these diseases to provide future risk assessment and family counseling.


Assuntos
Acidente Vascular Cerebral , Causalidade , Testes Genéticos , Humanos , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/genética
3.
Nanotechnology ; 29(32): 325601, 2018 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-29761791

RESUMO

Carbon nano-onions (CNOs), in their spherical or polyhedral forms, represent an important class of nanomaterials, due to their peculiar physical and electrochemical properties. Among the different methods of production, arc discharge between graphite electrodes sustained by deionized water is one of the most promising to obtain good quality CNOs in gram quantities. We applied the method with the aim to optimize the production of CNOs, using an innovative experimental arrangement. The discharges generate dispersed nanomaterials and a black hard cathodic deposit, which were studied by transmission electron microscopy-high-resolution TEM, scanning electron microscopy, Raman, thermogravimetric analysis and energy-dispersive x-ray spectroscopy. A simple mechanical grinding of the deposits permitted us to obtain turbostratic polyhedral CNOs that exhibited higher stability towards burning in air, compared to CNOs found in water. We propose a mechanism for the formation of the CNOs present in the deposit, in which the crystallization is driven by a strong temperature gradient existing close to the cathode surface at the beginning of the process, and subsequently close to the deposit surface whenever it is growing.

4.
J Nanosci Nanotechnol ; 18(4): 3006-3011, 2018 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-29442987

RESUMO

We present a study of adsorption of Cresyl Violet (CV) in aqueous solution on sonicated Graphite Oxide (sGO). For comparison, we also show adsorption results of Methylene Blue (MB) and Acridine Orange (AO) performed in the same conditions. The adsorbent was synthesized by the Tour's method followed by washing in water and ethanol and sonication, without any reduction, and studied by Raman, IR, UV-Vis, SEM and TEM techniques. Our results show that adsorption fits the pseudosecond order model for the three dyes, and that the adsorption quantity for CV is 125.0 mg g-1, while for MB and AO is 123.3 and 94.6 mg g-1 respectively.

5.
Sci Rep ; 7(1): 3445, 2017 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-28611385

RESUMO

We have investigated the electronic response of single crystals of indium selenide by means of angle-resolved photoemission spectroscopy, electron energy loss spectroscopy and density functional theory. The loss spectrum of indium selenide shows the direct free exciton at ~1.3 eV and several other peaks, which do not exhibit dispersion with the momentum. The joint analysis of the experimental band structure and the density of states indicates that spectral features in the loss function are strictly related to single-particle transitions. These excitations cannot be considered as fully coherent plasmons and they are damped even in the optical limit, i.e. for small momenta. The comparison of the calculated symmetry-projected density of states with electron energy loss spectra enables the assignment of the spectral features to transitions between specific electronic states. Furthermore, the effects of ambient gases on the band structure and on the loss function have been probed.

6.
Environ Monit Assess ; 186(9): 5731-47, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24865384

RESUMO

The Fusaro Lagoon is a shallow lagoon, located in SW Italy, largely influenced in the last decades by several anthropic impacts. The study examined the pollution status of the lagoon, during year 2011-2012 at nine sampling stations with the aim to find out proper measurements of water lagoon restoration. Concentrations of heavy metals (HMs) (aluminium [Al], barium [Ba], cadmium [Cd], copper [Cu], iron [Fe], manganese [Mn], vanadium [V] and zinc [Zn]) were examined in water, sediments and specimens of the ascidian Ciona intestinalis sp. A. Low levels of dissolved oxygen concentration were detected at many stations, with mean values of 5.2-6.4 mg L(-1). The redox potential of surface waters was also low, -2.7 to 50.7 mV. Sediments possessed high organic matter content, 17.7-29.4%. In sediments, the mean Zn level, 251.4 mg kg(-1), was about sixfold higher than that recorded in year 2000 (38.5 mg kg(-1)) and considerably higher than that recorded in 2007 (191 mg kg(-1)). The mean levels of Cd were outstandingly high, with a mean value of 70.5 mg kg(-1), about 30- and 50-fold higher than those determined in 2000 and 2007, respectively. Cadmium (Cd), Cu and nickel (Ni) appeared in excess with respect to most current guidelines, reaching significant pollution levels. C. intestinalis sp. A was detected only at few stations, with metals accumulated preferentially in the body in respect to the tunic, from 1.2 times for Zn (178 mg kg(-1)) to 4.0 times for V (304 mg kg(-1)). Data suggests the necessity of an immediate action of eco-compatible interventions for environmental restoration.


Assuntos
Monitoramento Ambiental , Metais Pesados/análise , Poluentes Químicos da Água/análise , Alumínio/análise , Cádmio/análise , Cobre/análise , Sedimentos Geológicos/química , Ferro/análise , Itália , Manganês/análise , Níquel/análise , Vanádio , Zinco/análise
7.
J Phys Condens Matter ; 25(11): 115301, 2013 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-23399885

RESUMO

Core-hole induced electron excitations in fullerene molecules, and small-diameter conducting carbon nanotubes, are studied using density functional theory with minimal, split-valence, and triply-split-valence basis sets plus the generalized gradient approximation by Perdew-Burke-Ernzerhof for exchange and correlation. Finite-size computations are performed on the carbon atoms of a C(60) Bucky ball and a piece of (3, 3) armchair cylindrical network, terminated by hydrogen atoms, while periodically boundary conditions are imposed on a (3, 3) nanotube unit cell. Sudden creation of the core state is simulated by replacing a 1s electron pair, localized at a central site of the structures, with the effective pseudo-potentials of both neutral and ionized atomic carbon. Excited states are obtained from the ground-state (occupied and empty) electronic structure of the ionized systems, and their overlaps with the ground state of the neutral systems are computed. These overlaps enter Fermi's golden rule, which is corrected with lifetime and finite-temperature effects to simulate the many-electron response of the nanoobjects. A model based on the linked cluster expansion of the vacuum persistence amplitude of the neutral systems, in a parametric core-hole perturbation, is developed and found to be reasonably consistent with the density functional theory method. The simulated spectrum of the fullerene molecule is found to be in good agreement with x-ray photoemission experiments on thick C(60) films, reproducing the low energy satellites at excitation energies below 4 eV within a peak position error of ca. 0.3 eV. The nanotube spectra show some common features within the same experiments and describe well the measured x-ray photoelectron lineshape from nanotube bundles with an average diameter of 1.2 nm.

8.
Bioinformatics ; 28(1): 142-4, 2012 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-22057158

RESUMO

SUMMARY: The Atlas of UTR Regulatory Activity (AURA) is a manually curated and comprehensive catalog of human mRNA untranslated regions (UTRs) and UTR regulatory annotations. Through its intuitive web interface, it provides full access to a wealth of information on UTRs that integrates phylogenetic conservation, RNA sequence and structure data, single nucleotide variation, gene expression and gene functional descriptions from literature and specialized databases. AVAILABILITY: http://aura.science.unitn.it CONTACT: aura@science.unitn.it; dassi@science.unitn SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Assuntos
Bases de Dados Genéticas , RNA Mensageiro/genética , Software , Regiões não Traduzidas , Humanos , Internet , Filogenia , RNA Mensageiro/química , RNA Mensageiro/metabolismo
9.
Rapid Commun Mass Spectrom ; 25(4): 483-8, 2011 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-21259356

RESUMO

Rotundone is an oxygenated sesquiterpene belonging to the family of guaianes, giving the 'peppery' aroma to white and black pepper and to red wines. Here we describe a novel, convenient protocol for the synthesis of rotundone, starting from a commercially available compound and requiring only two reaction steps, and an improved, faster method of GC separation (30 min) with selective quantisation of rotundone using tandem mass spectrometry in multiple reaction monitoring (MRM) mode with d(5)-rotundone as internal standard. With limits of detection (LODs) of 1.5 ng/L in white wine and 2.0 ng/L in red wine, intraday repeatability CV values of 6% and 5% at 50 ng/L and 500 ng/L and interday repeatability CV values of 13% and 6% at 50 ng/L and 500 ng/L, respectively, the improved protocol provides the desired sensitivity and selectivity for routine analysis of rotundone in both white and red wines. Initial application of this method highlighted the presence of unexpectedly high concentrations of rotundone, thus explaining the origin of the distinctive peppery aroma in Schioppettino and Vespolina red wines and in Gruener Veltliner white wines.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Sesquiterpenos/análise , Microextração em Fase Sólida/métodos , Vinho/análise , Análise de Alimentos/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Sesquiterpenos/química , Espectrometria de Massas em Tandem
10.
J Nanosci Nanotechnol ; 11(10): 9256-9, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22400333

RESUMO

We report on kinetic energy distributions of electrons emitted during bombardment of graphene adsorbed on a Ni(111) surface by 0.5-0.9 keV electrons. The spectra reveal several peaks superimposed on the background of cascade electrons. The position of these peaks does not depend significantly on primary electron energy but show a remarkable angular dependence, indicating that they are directly related to the empty bands above the vacuum level of the sample.

11.
Neurol Sci ; 30 Suppl 1: S109-11, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19415438

RESUMO

Many lines of research have suggested a relationship between migraine with aura (MA) and patent foramen ovale. Right-to-left shunt (RLS) of blood might explain both the occurrence of MA attacks, as well as the increased risk of ischaemic stroke in these patients. We evaluated the prevalence and the characteristics of RLS in a series of 120 MA patients, who were studied with contrast-enhanced Transcranial Doppler examination. We found RLS in 61 of them. A latent RLS was found in 28%, a permanent RLS in 72%, a shower-curtain pattern was detected in 52% of the studied patients.


Assuntos
Forame Oval Patente/epidemiologia , Enxaqueca com Aura/epidemiologia , Adulto , Feminino , Forame Oval Patente/diagnóstico por imagem , Humanos , Itália/epidemiologia , Masculino , Enxaqueca com Aura/diagnóstico por imagem , Prevalência , Estudos Prospectivos , Ultrassonografia Doppler Transcraniana
13.
Brain Res ; 919(2): 259-68, 2001 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-11701138

RESUMO

202W92 (R-(-)-2,4-diamino-6-(fluromethyl)-5-(2,3,5-trichlorophenyl)pyrimidine) is a novel compound in the same chemical series as the antiepileptic drug lamotrigine and the neuroprotective sipatrigine. Here 202W92 was quantitatively assessed as a neuroprotective agent in focal cerebral ischaemia, and as an inhibitor of sodium and calcium channels and of synaptic transmission. In the rat permanent middle cerebral artery occlusion (MCAO) model of acute focal ischaemia, 202W92 reduced infarct volume by 75% in cortex and by 80% in basal ganglia, with ED(50) approximately 2 mg/kg (single i.v. dose, 10 min post-occlusion). In whole-cell current recordings from single cells, 202W92 completely and reversibly inhibited voltage gated sodium channels (IC(50) 3 x 10(-6) M) in rat freshly-isolated cortical neurons and in the GH(3) pituitary cell line. 202W92 also inhibited a nifedipine-sensitive fraction (approximately 35%) of native high-voltage-activated (HVA) calcium current in rat cortical neurons (IC(50) 15 x 10(-6) M) and weakly inhibited low-voltage-activated (LVA) calcium currents of the recombinant alpha1I-mediated T-type (IC(50)>100 x 10(-6) M). The drug inhibited the amplitude and frequency of 4-aminopyridine-evoked glutamatergic excitatory post-synaptic currents (EPSCs). In conclusion, 202W92 is an effective neuroprotective agent when administered post-ischaemia and a potent sodium channel inhibitor in vitro.


Assuntos
Isquemia Encefálica/tratamento farmacológico , Canais de Cálcio/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Pirimidinas/farmacologia , Bloqueadores dos Canais de Sódio , Transmissão Sináptica/efeitos dos fármacos , Telencéfalo/efeitos dos fármacos , Animais , Isquemia Encefálica/metabolismo , Isquemia Encefálica/fisiopatologia , Bloqueadores dos Canais de Cálcio/farmacologia , Canais de Cálcio/metabolismo , Células Cultivadas/efeitos dos fármacos , Células Cultivadas/metabolismo , Infarto Cerebral/tratamento farmacológico , Infarto Cerebral/metabolismo , Infarto Cerebral/fisiopatologia , Relação Dose-Resposta a Droga , Potenciais Pós-Sinápticos Excitadores/efeitos dos fármacos , Potenciais Pós-Sinápticos Excitadores/fisiologia , Ácido Glutâmico/metabolismo , Infarto da Artéria Cerebral Média/tratamento farmacológico , Infarto da Artéria Cerebral Média/metabolismo , Infarto da Artéria Cerebral Média/fisiopatologia , Masculino , Potenciais da Membrana/efeitos dos fármacos , Potenciais da Membrana/fisiologia , Degeneração Neural/tratamento farmacológico , Degeneração Neural/metabolismo , Degeneração Neural/fisiopatologia , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Técnicas de Patch-Clamp , Ratos , Ratos Endogâmicos F344 , Canais de Sódio/metabolismo , Substância Negra/efeitos dos fármacos , Substância Negra/metabolismo , Substância Negra/fisiopatologia , Transmissão Sináptica/fisiologia , Telencéfalo/metabolismo , Telencéfalo/fisiopatologia
14.
J Neurophysiol ; 85(6): 2490-7, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11387395

RESUMO

Metabotropic glutamate receptors (mGluRs) modulate neuronal function via different transduction mechanisms that are either dependent or independent on G-protein function. Here we investigated, using whole cell patch-clamp recordings in combination with fluorimetric measurements of intracellular calcium concentration ([Ca(2+)](i)), the metabolic pathways involved in the responses induced by group I mGluRs in dopamine neurons of the rat midbrain. The inward current and the [Ca(2+)](i) increase caused by the group I mGluR agonist (S)-3,5-dihydroxyphenylglycine (DHPG, 100 microM) were permanently activated and subsequently abolished in cells loaded with the nonhydrolizable GTP-analogue GTP-gamma-S (600 microM). In addition, when GDP-beta-S (600 microM) was dialyzed into the cells to produce the blockade of the G proteins, the DHPG-dependent responses were reduced. When the tissue was bathed with the phospholipase C inhibitor 1-[6[[(17 beta)-3-methoxyestra-1,3,5(10)-trien-17-yl]amino]exyl]-1H-pyrrole-2,5-dione (10 microM), the DHPG-induced calcium transients slightly diminished but the associated inward currents were not affected. Interestingly, a substantial depression of the DHPG-induced inward current and transient increase of [Ca(2+)](i) was caused by the protein tyrosine kinase inhibitors tyrphostin B52 (40 microM) and 4',5,7-trihydroxyisoflavone (genistein; 40 microM), whereas genistein's inactive analogue 4',5,7-trihydroxyisoflavone-7-glucoside (40 microM) was ineffective. The blockade of the Src family of tyrosine kinase by 4-amino-5-(4-methylphenyl)-7-(t-butyl)pyrazolo[3,4-d]pyrimidine (20 microM), mitogen-activated protein kinase by 2'-amino-3' methoxyflavone (50 microM), and protein kinase C by staurosporine (1 microM) had no effect on the cellular responses caused by DHPG. The mGluR5-selective antagonist 2-methyl-6-(phenylethynyl)-pyridine (10--100 microM) did not affect the actions of DHPG. Thus our results indicate that the responses, mainly mediated by mGluRs1 in dopamine neurons, are activated by intracellular mechanisms coupled to G proteins and regulated by tyrosine kinases.


Assuntos
Dopamina/fisiologia , Proteínas de Ligação ao GTP/metabolismo , Guanosina Difosfato/análogos & derivados , Neurônios/enzimologia , Proteínas Tirosina Quinases/metabolismo , Receptores de Glutamato Metabotrópico/metabolismo , Animais , Ativação Enzimática/fisiologia , Inibidores Enzimáticos/farmacologia , Estrenos/farmacologia , Antagonistas de Aminoácidos Excitatórios/farmacologia , Feminino , Genisteína/farmacologia , Glicina/análogos & derivados , Glicina/farmacologia , Guanosina 5'-O-(3-Tiotrifosfato)/farmacologia , Guanosina Difosfato/farmacologia , Masculino , Potenciais da Membrana/efeitos dos fármacos , Potenciais da Membrana/fisiologia , Mesencéfalo/citologia , Técnicas de Patch-Clamp , Inibidores de Fosfodiesterase/farmacologia , Proteína Quinase C/metabolismo , Pirrolidinonas/farmacologia , Ratos , Ratos Wistar , Resorcinóis/farmacologia , Tionucleotídeos/farmacologia , Fosfolipases Tipo C/metabolismo , Tirfostinas/farmacologia
16.
Eur J Surg ; 164(2): 127-32, 1998 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9537720

RESUMO

OBJECTIVE: To assess the function of the pylorus after pylorus-preserving pancreaticoduodenectomy (PPPD) done for periampullary or pancreatic cancer. DESIGN: Prospective, observational controlled clinical study. SETTING: Teaching hospital, Italy. SUBJECTS: 17 patients who had undergone PPPD, and 15 healthy control subjects. INVESTIGATIONS: Endoscopy to check for gastritis and marginal ulcers and 24 h-pH monitoring and 99mTc HIDA scintigraphy to detect jejunogastric reflux. Scintigraphy was also used to evaluate gastric and jejunal transit after a solid meal labelled with 99mTc colloid sulphur. MAIN OUTCOME MEASURES: Signs of delayed gastric emptying, jejunogastric reflux and gastric outlet obstruction in the short and long term. RESULTS: In the early postoperative period only 1 patient had delayed gastric emptying. In the long term, two patients had symptoms of dyspepsia and 8/11 showed alkaline reflux with persistent gastric pH more than 4 for more than 12 hours; 3 had histological signs of gastritis. There was no difference in gastric emptying compared with controls, but three patients had prolonged emptying time (T1/2 more than 85 minutes). Endoscopy findings correlated with pH monitoring results. CONCLUSIONS: After PPPD, most patients have abnormal pyloric function, but it is clinically evident in only a small proportion.


Assuntos
Pancreaticoduodenectomia/métodos , Piloro/fisiologia , Adulto , Idoso , Ampola Hepatopancreática , Neoplasias do Ducto Colédoco/cirurgia , Dispepsia/etiologia , Feminino , Esvaziamento Gástrico/fisiologia , Obstrução da Saída Gástrica/etiologia , Humanos , Jejuno/fisiologia , Masculino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/cirurgia , Complicações Pós-Operatórias , Período Pós-Operatório , Estudos Prospectivos , Estômago/fisiologia
17.
Comput Nurs ; 10(5): 219-24, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1393804

RESUMO

The authors believe that for computer assisted instruction to be an effective instructional tool, it must incorporate the most current theoretical principles related to learning and instruction. To assist future developers of computer assisted instruction, the authors review some of the major constructs from the theoretical foundations of various disciplines and then illustrate the integration of these constructs in the design of a software program entitled SOS--Strategies for Problem Solving.


Assuntos
Instrução por Computador , Educação em Enfermagem , Design de Software , Illinois , Microcomputadores
19.
Adv Clin Care ; 4(5): 34-5, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2789638

RESUMO

This article discusses the development of the computer program titled TLC General Hospital, then offers hints and ideas for nurses contemplating the development of their own instructional packages.


Assuntos
Simulação por Computador , Capacitação de Usuário de Computador , Educação em Enfermagem , Sistemas de Informação Hospitalar , Design de Software , Software , Humanos
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