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1.
J Neural Eng ; 8(3): 036018, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21543839

RESUMO

A bi-directional neural interface (NI) system was designed and prototyped by incorporating a novel neural recording and processing subsystem into a commercial neural stimulator architecture. The NI system prototype leverages the system infrastructure from an existing neurostimulator to ensure reliable operation in a chronic implantation environment. In addition to providing predicate therapy capabilities, the device adds key elements to facilitate chronic research, such as four channels of electrocortigram/local field potential amplification and spectral analysis, a three-axis accelerometer, algorithm processing, event-based data logging, and wireless telemetry for data uploads and algorithm/configuration updates. The custom-integrated micropower sensor and interface circuits facilitate extended operation in a power-limited device. The prototype underwent significant verification testing to ensure reliability, and meets the requirements for a class CF instrument per IEC-60601 protocols. The ability of the device system to process and aid in classifying brain states was preclinically validated using an in vivo non-human primate model for brain control of a computer cursor (i.e. brain-machine interface or BMI). The primate BMI model was chosen for its ability to quantitatively measure signal decoding performance from brain activity that is similar in both amplitude and spectral content to other biomarkers used to detect disease states (e.g. Parkinson's disease). A key goal of this research prototype is to help broaden the clinical scope and acceptance of NI techniques, particularly real-time brain state detection. These techniques have the potential to be generalized beyond motor prosthesis, and are being explored for unmet needs in other neurological conditions such as movement disorders, stroke and epilepsy.


Assuntos
Encéfalo/fisiopatologia , Terapia por Estimulação Elétrica/instrumentação , Eletroencefalografia/instrumentação , Doença de Parkinson/fisiopatologia , Doença de Parkinson/reabilitação , Próteses e Implantes , Terapia Assistida por Computador/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento , Humanos , Doença de Parkinson/diagnóstico
2.
Cephalalgia ; 27(6): 535-41, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17459083

RESUMO

The aim was to analyse the socioeconomic burden of cluster headache in patients from a tertiary headache centre. One hundred consecutive patients from the Danish Headache Centre were invited to an interview about the socioeconomic impact of cluster headache. Work absence and use of medical services were compared with a Danish population-based survey. Eighty-five patients participated; 78% reported restrictions in daily living and 13% also outside of cluster periods; 25% reported a major decrease in their ability to participate in social activities, family life and housework. The disease caused lifestyle changes for 96%, most frequently in sleeping habits and avoidance of alcohol. The absence rate among patients was 30%, which was significantly higher than 12% among the general population (P < 0.001). Use of health services due to headache was also higher among the patients (P < 0.001). Cluster headache, although periodic in most cases, has considerable impact on social functions, quality of life and use of healthcare.


Assuntos
Atividades Cotidianas/psicologia , Cefaleia Histamínica/psicologia , Efeitos Psicossociais da Doença , Qualidade de Vida/psicologia , Adulto , Idoso , Cefaleia Histamínica/epidemiologia , Dinamarca/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Clínicas de Dor/estatística & dados numéricos , Licença Médica/estatística & dados numéricos
3.
Brain ; 130(Pt 2): 346-56, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17142831

RESUMO

Familial hemiplegic migraine (FHM) is a rare subtype of migraine with aura and transient hemiplegia. FHM mutations are known in three genes, the CACNA1A (FHM1) gene, the ATP1A2 (FHM2) and the SCN1A (FHM3) gene and seem to have an autosomal-dominant mode of inheritance. The aim of this study was to search for FHM mutations in FHM families identified through a screen of the Danish population of 5.2 million people. FHM patients were diagnosed according to the International Classification of Headache Disorders and all FHM patients had a physical and neurological examination by a physician. A total of 147 FHM patients from 44 different families were identified; 43 FHM families participated in this study. Linkage analysis of these families shows clear linkage to the FHM locus (FHM1) on chromosome 19, supportive linkage to the FHM2 locus whereas no linkage was found to the FHM3 locus. Furthermore, we sequenced all exons and promoter regions of the CACNA1A and ATP1A2 genes and screened for the Q1489K mutation in the SCN1A gene. CACNA1A gene mutations were identified in three of the FHM families, two known FHM mutations, R583Q and T666M and one novel C1369Y mutation. Three FHM families were identified with novel mutations in the ATP1A2 gene; a family with a V138A mutation, a family with a R202Q mutation and a family with a R763C mutation. None of the Danish FHM families have the Q1489K mutation in the SCN1A gene. Our study shows that only 14% (6/42) of FHM families in the general Danish population have exonic FHM mutations in the CACNA1A or ATP1A2 gene. The families we identified with FHM mutations in the CACNA1A and ATP1A2 genes were extended, multiple affected families whereas the remaining FHM families were smaller. The existence of many small families in the Danish FHM cohort may reflect less bias in FHM family ascertainment and/or more locus heterogeneity than described previously.


Assuntos
Hemiplegia/genética , Enxaqueca com Aura/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Canais de Cálcio/genética , Criança , Análise Mutacional de DNA , Feminino , Ligação Genética , Genótipo , Hemiplegia/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Enxaqueca com Aura/complicações , Mutação , Linhagem , ATPase Trocadora de Sódio-Potássio/genética
5.
Med Parazitol (Mosk) ; (3): 11-5, 2001.
Artigo em Russo | MEDLINE | ID: mdl-11680364

RESUMO

The heterogeneity of the Ixodes persulcatus population in the vicinity of Saint Petersburg was estimated by using malate dehydrogenase (MDH) isoenzyme. There are six MDH genotypes carrying 3 alleles in the Ixodes persulcatus population. The prevalence of Borrelia and Ehrlichia species in the study genotypes was analyzed. There was a difference in the prevalence and intensity of infection. The greatest abundance of Borrelia was described in the genotypes to Genogroup 1 (with allele 1). Among them, heterozygous ticks were most intensively infected. Polymerase chain reaction identified species pathogenic for man. These included 3 species of Borrelia: B. afzelii, B. garinii, and B. burgdorferi sensu stricto and 2 species of Ehrlichia muris and HGE agent. The author are the first to describe HGE agent and B. burgdorfei ss encountered in Russia.


Assuntos
Ehrlichia/genética , Ixodes/genética , Ixodes/microbiologia , Animais , Borrelia/classificação , Borrelia/genética , Reservatórios de Doenças , Ehrlichia/classificação , Imunofluorescência , Genótipo , Humanos , Isoenzimas/genética , Malato Desidrogenase/genética , Reação em Cadeia da Polimerase , Federação Russa
6.
Bioorg Med Chem Lett ; 11(11): 1355-8, 2001 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-11378353

RESUMO

Peptidyl deformylase (PDF) is a metallo protease that catalyzes the removal of a formyl group from the N-termini of prokaryotic prepared polypeptides, an essential step in bacterial protein synthesis. Screening of our compound collection using Staphylococcus aureus PDF afforded a very potent inhibitor with an IC(50) in the low nanomolar range. Unfortunately, the compound that contains a hydroxamic acid did not exhibit antibacterial activity (MIC). In order to address the lack of activity in the MIC assay and to determine what portion of the molecule was responsible for binding to PDF, we prepared several analogues. This paper describes our findings that the hydroxamic acid functionality found in 1 is mainly responsible for the high affinity to PDF. In addition, we identified an alternative class of PDF inhibitors, the N-hydroxy urea 18, which has both PDF and antibacterial activity.


Assuntos
Amidoidrolases , Aminopeptidases/antagonistas & inibidores , Antibacterianos/farmacologia , Ácidos Hidroxâmicos/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Aminopeptidases/química , Antibacterianos/síntese química , Antibacterianos/química , Ácidos Hidroxâmicos/síntese química , Ácidos Hidroxâmicos/química , Metaloendopeptidases/antagonistas & inibidores , Testes de Sensibilidade Microbiana , Modelos Moleculares , Conformação Proteica , Staphylococcus aureus/enzimologia , Relação Estrutura-Atividade
7.
J Med Chem ; 41(19): 3727-35, 1998 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-9733498

RESUMO

Oxazolidinones are a novel class of synthetic antibacterial agents active against gram-positive organisms including methicillin-resistant Staphylococcus aureus as well as selected anaerobic organisms. Important representatives of this class include the morpholine derivative linezolid 2, which is currently in phase III clinical trials, and the piperazine derivative eperezolid 3. As part of an investigation of the structure-activity relationships of structurally related oxazolidinones, we have prepared and evaluated the antibacterial properties of a series of piperazinyl oxazolidinones in which the distal nitrogen of the piperazinyl ring is substituted with a six-membered heteroaromatic ring. Compounds having MIC values

Assuntos
Antibacterianos/síntese química , Oxazóis/síntese química , Oxazolidinonas , Piperazinas/síntese química , Acetamidas/farmacologia , Antibacterianos/química , Antibacterianos/metabolismo , Antibacterianos/farmacologia , Células CACO-2 , Enterococcus faecalis/efeitos dos fármacos , Humanos , Linezolida , Resistência a Meticilina , Testes de Sensibilidade Microbiana , Oxazóis/química , Oxazóis/metabolismo , Oxazóis/farmacologia , Permeabilidade , Piperazinas/química , Piperazinas/metabolismo , Piperazinas/farmacologia , Piridinas/síntese química , Piridinas/química , Piridinas/metabolismo , Piridinas/farmacologia , Infecções Estafilocócicas/tratamento farmacológico , Staphylococcus aureus/efeitos dos fármacos , Streptococcus pneumoniae/efeitos dos fármacos , Relação Estrutura-Atividade , Triazenos/síntese química , Triazenos/química , Triazenos/metabolismo , Triazenos/farmacologia
8.
Percept Psychophys ; 59(5): 714-20, 1997 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9259638

RESUMO

Subjects were presented with briefly exposed visual displays of words that were common first names with a length of four to six letters. In the main experiment, each display consisted of four words: two names shown in red and two shown in white. The subject's task was to report the red names (targets), but ignore the white ones (distractors). On some trials the subject's own name appeared as a display item (target or distractor). Presentation of the subject's name as a distractor caused no more interference with report of targets than did presentation of other names as distractors. Apparently, visual attention was not automatically attracted by the subject's own name.


Assuntos
Atenção , Automatismo , Nomes , Percepção Visual , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mascaramento Perceptivo
9.
Biochemistry ; 29(11): 2852-60, 1990 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-2346749

RESUMO

The binding of the antitumor drug CC-1065 has been studied with nuclear magnetic resonance (NMR) spectroscopy. This study involves two parts, the elucidation of the covalent binding site of the drug to DNA and a detailed investigation of the noncovalent interactions of CC-1065 with a DNA fragment through analysis of 2D NOE (NOESY) experiments. A CC-1065-DNA adduct was prepared, and an adenine adduct was released upon heating. NMR (1H and 13C) analysis of the adduct shows that the drug binds to N3 of adenine by reaction of its cyclopropyl group. The reaction pathway and product formed were determined by analysis of the 13C DEPT spectra. An octamer duplex, d(CGATTAGC.GCTAATCG), was synthesized and used in the interaction study of CC-1065 and the oligomer. The duplex and the drug-octamer complex were both analyzed by 2D spectroscopy (COSY, NOESY). The relative intensity of the NOEs observed between the drug (CC-1065) and the octamer duplex shows conclusively that the drug is located in the minor groove, covalently attached to N3 of adenine 6 and positioned from the 3'----5' end in relation to strand A [d(CGATTA6GC)]. A mechanism for drug binding and stabilization can be inferred from the NOE data and model-building studies.


Assuntos
Adenina/análogos & derivados , Antibióticos Antineoplásicos/metabolismo , Adutos de DNA , DNA/metabolismo , Indóis , Leucomicinas/metabolismo , Sequência de Bases , Fenômenos Químicos , Química , Duocarmicinas , Espectroscopia de Ressonância Magnética/métodos , Dados de Sequência Molecular , Conformação de Ácido Nucleico
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