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1.
Rev Neurol (Paris) ; 171(12): 832-40, 2015 Dec.
Artigo em Francês | MEDLINE | ID: mdl-26612553

RESUMO

We report a case of inflammatory cerebral amyloid angiopathy (CAA) that led to rapid cognitive decline, seizures, visual hallucinations, hyperproteinorrachia and right hemispheric leukopathy. Brain biopsy gave the diagnosis of CAA. Although no inflammatory infiltrate was found in the biopsy sample, corticosteroids led to a regression of the radiological lesions without significant clinical improvement. CAA is a rare disease, defined by lesions of classical cerebral amyloid angiopathy and perivascular infiltrates in contact with the affected vessels. In cases of rapidly progressive dementia associated with leukopathy, inflammatory amyloid angiopathy should be considered as cognitive disorders may improve after immunosuppressive therapy.


Assuntos
Angiopatia Amiloide Cerebral/patologia , Demência/patologia , Corticosteroides/uso terapêutico , Idoso de 80 Anos ou mais , Biópsia , Angiopatia Amiloide Cerebral/psicologia , Transtornos Cognitivos/etiologia , Transtornos Cognitivos/psicologia , Demência/psicologia , Progressão da Doença , Feminino , Humanos , Imunossupressores/uso terapêutico
2.
Space Sci Rev ; 215(1): 12, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30880848

RESUMO

By the end of 2018, 42 years after the landing of the two Viking seismometers on Mars, InSight will deploy onto Mars' surface the SEIS (Seismic Experiment for Internal Structure) instrument; a six-axes seismometer equipped with both a long-period three-axes Very Broad Band (VBB) instrument and a three-axes short-period (SP) instrument. These six sensors will cover a broad range of the seismic bandwidth, from 0.01 Hz to 50 Hz, with possible extension to longer periods. Data will be transmitted in the form of three continuous VBB components at 2 sample per second (sps), an estimation of the short period energy content from the SP at 1 sps and a continuous compound VBB/SP vertical axis at 10 sps. The continuous streams will be augmented by requested event data with sample rates from 20 to 100 sps. SEIS will improve upon the existing resolution of Viking's Mars seismic monitoring by a factor of ∼ 2500 at 1 Hz and ∼ 200 000 at 0.1 Hz. An additional major improvement is that, contrary to Viking, the seismometers will be deployed via a robotic arm directly onto Mars' surface and will be protected against temperature and wind by highly efficient thermal and wind shielding. Based on existing knowledge of Mars, it is reasonable to infer a moment magnitude detection threshold of M w ∼ 3 at 40 ∘ epicentral distance and a potential to detect several tens of quakes and about five impacts per year. In this paper, we first describe the science goals of the experiment and the rationale used to define its requirements. We then provide a detailed description of the hardware, from the sensors to the deployment system and associated performance, including transfer functions of the seismic sensors and temperature sensors. We conclude by describing the experiment ground segment, including data processing services, outreach and education networks and provide a description of the format to be used for future data distribution. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s11214-018-0574-6) contains supplementary material, which is available to authorized users.

3.
Waste Manag ; 68: 518-526, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28669497

RESUMO

A parallel study of acidic and alkaline leaching for the recovery of Mn and Zn from spent alkaline batteries is outlined. Using H2SO4 as solvent and selecting appropriate conditions of temperature and concentration, all residues were dissolved except carbon. The separation and recovery of the two components were performed by electrodeposition with satisfactory results at pH values above 4 (current efficiency above 70% for Zn and Mn) but rather lower efficiencies as the pH decreased. Most of the Zn was selectively dissolved by alkaline leaching using a 6.5M NaOH solution, and its recovery was examined by means of both electrochemical and chemical processes. The expected formation of pure Zn by electrowinning failed due to the formation of ZnO, the content of which was highly dependent on the electrodeposition time. For short periods, Zn was the main component. For longer periods the electrodeposit consisted of agglomerated microparticles of ZnO with a minor fraction of Zn metal (barely 3% as measured by X-ray diffraction). A chemical reaction of the element with oxygen released at the anode surface might be responsible for its conversion to ZnO. A simple chemical route is described for the first time for the direct conversion of Zn(OH)42- solution to nanostructured ZnO by lowering the pH to values around 12 using 2M HCl solution.


Assuntos
Fontes de Energia Elétrica , Manganês , Zinco , Ácidos , Eletrodos , Reciclagem , Difração de Raios X
4.
Arch Inst Pasteur Tunis ; 83(1-4): 41-7, 2006.
Artigo em Francês | MEDLINE | ID: mdl-19388596

RESUMO

The nasopharyngeal carcinoma (NPC) is frequent in Tunisia. It's the second ORL cancer of men after the larynx one. To analyse the NPC characteristics in our population, we determined the frequency of EBV infection in 47 paraffin-embedded and 6 fresh NPC biopsies. We first extracted the DNA from tumoral tissus and then amplified viral sequences by PCR to detect and to type the infecting virus (EBV-A or ABV-B). Our results showed that amplifiable DNA has been obtained from 34/47 paraffin-embedded NPC biopsies while 13/47 of the others biopsies contained degraded and not amplifiable DNA. All the fresh biopsies allowed to obtain DNA with good quality. The EBV infection frequency in paraffin-embedded NPC biopsies is 35% while EBV is detected in all fresh biopsies (6/6). Our analyse also showed that the EBV-A is predominant in our population compared to EBV-B as it was shown in most countries of the world. This study clearly shows that PCR results obtained with paraffin-embedded NPC biopsies are divergeant from those obtained with fresh biopsies. Because of DNA degradation in paraffin-embedded NPC biopsies, the biology molecular results from that kind of samples is criticable. Moreover the results obtained from fresh NPC biopsies confirmed the quasi-constant association of EBV with undifferenciated carcinoma nasopharyngeal type.


Assuntos
Biópsia/métodos , Infecções por Vírus Epstein-Barr/diagnóstico , Infecções por Vírus Epstein-Barr/virologia , Neoplasias Nasofaríngeas/virologia , Inclusão em Parafina/métodos , Reação em Cadeia da Polimerase/métodos , Ácido Acético , Causalidade , DNA Viral/genética , Infecções por Vírus Epstein-Barr/complicações , Infecções por Vírus Epstein-Barr/epidemiologia , Fixadores , Formaldeído , Herpesvirus Humano 4/classificação , Herpesvirus Humano 4/genética , Humanos , Incidência , Neoplasias Nasofaríngeas/epidemiologia , Neoplasias Nasofaríngeas/patologia , Picratos , Tunísia/epidemiologia
5.
Biomaterials ; 17(9): 903-12, 1996 May.
Artigo em Inglês | MEDLINE | ID: mdl-8718936

RESUMO

Thrombus formation on blood-contacting artificial surfaces is a major problem. Antithrombogenic polymer surfaces have been obtained either by heparin binding, or by grafting sulphonate and/or amino acid sulphonamide groups on insoluble polystyrene. In addition to their capacity to adsorb thrombin, such surfaces were shown to be able to catalyse its inhibition by antithrombin III (AT), i.e. they are endowed with heparin-like activity. The results were mainly obtained by using clotting assays. In many cases, delineating adsorption and catalytic processes by such assays is not possible when evaluating anticoagulant polymer surfaces. To overcome this problem, the kinetics of thrombin adsorption and inhibitions by AT and heparin cofactor II (HC) in the presence of such surfaces have been measured by using an assay performed with a thrombin-specific chromogenic substrate. A simple kinetic model of thrombin consumption is proposed. The relevant calculations, carried out with the help of a computer program, lead to determination of relative second order rate constants of thrombin adsorption and inhibitions by AT and HC in the presence of the polymers. In addition to thrombin adsorption, polystyrene surfaces bearing only sulphonate groups catalyse inhibition by AT, whereas polystyrene surfaces bearing either aspartate, glycinate or isophthalate sulphonamide groups catalyse both inhibitions by AT and HC.


Assuntos
Materiais Biocompatíveis/química , Heparina/administração & dosagem , Heparina/química , Polímeros/química , Trombina/antagonistas & inibidores , Adsorção , Anticoagulantes/administração & dosagem , Anticoagulantes/química , Antitrombina III/farmacologia , Catálise , Cofator II da Heparina/farmacologia , Humanos , Técnicas In Vitro , Cinética , Teste de Materiais , Modelos Biológicos , Poliestirenos/química , Propriedades de Superfície , Trombina/metabolismo , Trombina/farmacocinética , Trombose/prevenção & controle
6.
Biomaterials ; 11(6): 425-9, 1990 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2207233

RESUMO

Antithrombogenic functional polymer surfaces have been obtained by grafting heparin or by substituting insoluble polystyrene with sulphonate and/or amino acid sulphamide groups. Their heparin-like properties have been related to their catalytic effects on the antithrombin III - thrombin complex formation. Amongst these antithrombogenic surfaces, this study demonstrates that some insoluble amino acid sulphamide derivatives of polystyrene strongly potentiate heparin cofactor II, in addition to antithrombin III. In contrast, an insoluble polystyrene sulphonate and, to a lesser extent, an insoluble heparin copolymer, are better catalysts of antithrombin III. It is hypothesized that such different behaviours result from different conformations of the species adsorbed onto the surfaces. The conclusions support the possible use of such amino acid sulphamide groups to prepare antithrombogenic surfaces in contact with blood.


Assuntos
Materiais Biocompatíveis , Poliestirenos/química , Inibidores de Proteases/sangue , Tromboembolia/prevenção & controle , Antitrombina III/metabolismo , Cofator II da Heparina/metabolismo , Técnicas In Vitro , Propriedades de Superfície
7.
Biomaterials ; 13(6): 339-44, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1610956

RESUMO

Sulphonated polyurethanes have been shown to have excellent blood contacting properties. In this paper, similar polyurethanes which are water soluble have been investigated to determine their influence on thrombus formation. These polymers were shown to delay clotting times in the following ways: by direct complex formation between the polymer and thrombin; by interference with fibrin polymerization; and by complex interactions between polymer, thrombin, plasma antiproteases and fibrinogen in plasma.


Assuntos
Anticoagulantes/farmacologia , Materiais Biocompatíveis , Poliuretanos/farmacologia , Animais , Coagulação Sanguínea/efeitos dos fármacos , Cães , Fibrina/efeitos dos fármacos , Fibrina/metabolismo , Humanos , Técnicas In Vitro , Teste de Materiais , Poliuretanos/química , Ácidos Sulfônicos/farmacologia , Trombina/antagonistas & inibidores
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