Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 16 de 16
Filtrar
1.
Front Psychol ; 15: 1368080, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38840748

RESUMO

Grammatical redundancy is a widespread feature across languages. Although redundant cues can be seen to increase the complexity and processing burden of structures, it has been suggested that they can assist language acquisition. Here, we explored if this learning benefit can be observed from the very initial stages of second language (L2) acquisition and whether the effect of redundancy is modulated by the perceptual salience of the redundant linguistic cues. Across two experiments, three groups of adult native speakers of English were incidentally exposed to three different artificial languages; one that had a fixed word order, Verb-Object-Subject, and two in which thematic role assignment was additionally determined by a low-salient (Experiment 1) or a high-salient (Experiment 2) redundant case marker. While all groups managed to learn the novel language, our results pointed towards a hindering role of redundancy, with participants in the non-redundant condition achieving greater learning outcomes compared to those in both redundant conditions. Results also revealed that this impeding effect of redundancy on L2 learners can be attenuated by the salience of the redundant cue (Experiment 2). In conjunction with earlier findings, the present results suggest that the effect of redundancy on L2 acquisition can be differentially manifested depending on the stage of L2 development, learners' first language biases and age.

2.
Rev Esp Cardiol (Engl Ed) ; 77(1): 19-26, 2024 Jan.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-37380048

RESUMO

INTRODUCTION AND OBJECTIVES: Atrial fibrillation (AF) is linked to heart failure (HF). However, little has been published on the factors that may precipitate the onset of HF in AF patients. We aimed to determine the incidence, predictors, and prognosis of incident HF in older patients with AF with no prior history of HF. METHODS: Patients with AF older than 80 years and without prior HF were identified between 2014 and 2018. RESULTS: A total of 5794 patients (mean age, 85.2±3.8 years; 63.2% women) were followed up for 3.7 years. Incident HF, predominantly with preserved left ventricular ejection fraction, developed in 33.3% (incidence rate, 11.5-100 people-year). Multivariate analysis identified 11 clinical risk factors for incident HF, irrespective of HF subtype: significant valvular heart disease (HR, 1.99; 95%CI, 1.73-2.28), reduced baseline left ventricular ejection fraction (HR, 1.92; 95%CI, 1.68-2.19), chronic pulmonary obstructive disease (HR, 1.59; 95%CI, 1.40-1.82), enlarged left atrium (HR 1.47, 95%CI 1.33-1.62), renal dysfunction (HR 1.36, 95%CI 1.24-1.49), malnutrition (HR, 1.33; 95%CI, 1.21-1.46), anemia (HR, 1.30; 95%CI, 1.17-1.44), permanent AF (HR, 1.15; 95%CI, 1.03-1.28), diabetes mellitus (HR, 1.13; 95%CI, 1.01-1.27), age per year (HR, 1.04; 95%CI, 1.02-1.05), and high body mass index for each kg/m2 (HR, 1.03; 95%CI, 1.02-1.04). The presence of incident HF nearly doubled the mortality risk (HR, 1.67; 95%CI, 1.53-1.81). CONCLUSIONS: The presence of HF in this cohort was relatively frequent and nearly doubled the mortality risk. Eleven risk factors for HF were identified, expanding the scope for primary prevention among elderly patients with AF.


Assuntos
Fibrilação Atrial , Insuficiência Cardíaca , Disfunção Ventricular Esquerda , Humanos , Feminino , Idoso , Idoso de 80 Anos ou mais , Masculino , Fibrilação Atrial/complicações , Fibrilação Atrial/epidemiologia , Incidência , Volume Sistólico , Função Ventricular Esquerda , Insuficiência Cardíaca/tratamento farmacológico , Fatores de Risco , Prognóstico , Disfunção Ventricular Esquerda/complicações
3.
Lab Chip ; 23(22): 4821-4833, 2023 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-37846545

RESUMO

To accurately phenocopy human biology in vitro, researchers have been reducing their dependence on standard, static two-dimensional (2D) cultures and instead are moving towards three-dimensional (3D) and/or multicellular culture techniques. While these culture innovations are becoming more commonplace, there is a growing body of research that illustrates the benefits and even necessity of recapitulating the dynamic flow of nutrients, gas, waste exchange and tissue interactions that occur in vivo. However, cost and engineering complexity are two main factors that hinder the adoption of these technologies and incorporation into standard laboratory workflows. We developed LATTICE, a plug-and-play microfluidic platform able to house up to eight large tissue or organ models that can be cultured individually or in an interconnected fashion. The functionality of the platform to model both healthy and diseased tissue states was demonstrated using 3D cultures of reproductive tissues including murine ovarian tissues and human fallopian tube explants (hFTE). When exogenously exposed to pathological doses of gonadotropins and androgens to mimic the endocrinology of polycystic ovarian syndrome (PCOS), subsequent ovarian follicle development, hormone production and ovulation copied key features of this endocrinopathy. Further, hFTE cilia beating decreased significantly only when experiencing continuous media exchanges. We were then able to endogenously recreate this phenotype on the platform by dynamically co-culturing the PCOS ovary and hFTE. LATTICE was designed to be customizable with flexibility in 3D culture formats and can serve as a powerful automated tool to enable the study of tissue and cellular dynamics in health and disease in all fields of research.


Assuntos
Síndrome do Ovário Policístico , Feminino , Animais , Humanos , Camundongos , Síndrome do Ovário Policístico/metabolismo , Microfluídica , Técnicas de Cocultura
4.
Preprint em Inglês | bioRxiv | ID: ppbiorxiv-516726

RESUMO

The SARS-CoV-2 pandemic made evident that we count with few coronavirus-fighting drugs. Here we aimed to identify a cost-effective antiviral with broad spectrum activity and high safety and tolerability profiles. We began elaborating a list of 116 drugs previously used to treat other pathologies or characterized in pre-clinical studies with potential to treat coronavirus infections. We next employed molecular modelling tools to rank the 44 most promising inhibitors and tested their efficacy as antivirals against a panel of and {beta} coronavirus, e.g., the HCoV-229E and SARS-CoV-2 viruses. Four drugs, OSW-1, U18666A, hydroxypropyl-{beta}-cyclodextrin (H{beta}CD) and phytol, showed antiviral activity against both HCoV-229E (in MRC5 cells) and SARS-CoV-2 (in Vero E6 cells). The mechanism of action of these compounds was studied by transmission electron microscopy (TEM) and by testing their capacity to inhibit the entry of SARS-CoV-2 pseudoviruses in ACE2-expressing HEK-293T cells. The entry was inhibited by H{beta}CD and U18666A, yet only H{beta}CD could inhibit SARS-CoV-2 replication in the pulmonary cells Calu-3. With these results and given that cyclodextrins are widely used for drug encapsulation and can be safely administered to humans, we further tested 6 native and modified cyclodextrins, which confirmed {beta}-cyclodextrins as the most potent inhibitors of SARS-CoV-2 replication in Calu-3 cells. All accumulated data points to {beta}-cyclodextrins as promising candidates to be used in the therapeutic treatments for SARS-CoV-2 and possibly other respiratory viruses.

5.
Eur Heart J Cardiovasc Imaging ; 23(7): 979-988, 2022 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-35511547

RESUMO

AIMS: Severe tricuspid regurgitation (TR) has adverse effects on outcomes, with limited therapeutic options. We report the outcomes of patients undergoing percutaneous annuloplasty as a treatment of ≥severe functional TR in a single centre. METHODS AND RESULTS: Prospective, single-arm, single-centre study that enrolled 24 consecutive patients with at least severe functional TR undergoing percutaneous annuloplasty with Cardioband system between 2019 and 2021. Clinical and echocardiographic data were prospectively collected, with a mean follow-up of 279 ± 246 days. At baseline, 66.6% were in New York Heart Association (NYHA) Classes III and IV and 100% had significant oedema. Technical success was 91.6%. At the end of follow-up, there was one death. Echocardiography showed a significant reduction in septolateral annular diameter of 10.4 mm (P < 0.001) that remained stable at the end of follow-up. The severity of the TR was also reduced. About 81.8% of patients were in NYHA Classes I and II. The number of patients with significant oedema decreased to 46% (P = 0.01). Six-minute walk distance improved by 68.8 m (P = 0.12). CONCLUSION: Percutaneous annuloplasty with Cardioband system is an effective and safe treatment for patients with symptomatic, ≥severe functional TR. Annular reduction and TR severity reduction remained significant and sustained for 1 year. Patients experienced improvements in quality of life and exercise capacity.


Assuntos
Anuloplastia da Valva Cardíaca , Implante de Prótese de Valva Cardíaca , Insuficiência da Valva Tricúspide , Anuloplastia da Valva Cardíaca/métodos , Implante de Prótese de Valva Cardíaca/métodos , Humanos , Estudos Prospectivos , Qualidade de Vida , Resultado do Tratamento , Valva Tricúspide/diagnóstico por imagem , Valva Tricúspide/cirurgia , Insuficiência da Valva Tricúspide/diagnóstico por imagem , Insuficiência da Valva Tricúspide/etiologia , Insuficiência da Valva Tricúspide/cirurgia
6.
Sci Total Environ ; 773: 145351, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-33940724

RESUMO

Cabled observatories are marine infrastructures equipped with biogeochemical and oceanographic sensors as well as High-Definition video and audio equipment, hence providing unprecedented opportunities to study marine biotic and abiotic components. Additionally, non-invasive monitoring approaches such as environmental DNA (eDNA) metabarcoding have further enhanced the ability to characterize marine life. Although the use of non-invasive tools beholds great potential for the sustainable monitoring of biodiversity and declining natural resources, such techniques are rarely used in parallel and understanding their limitations is challenging. Thus, this study combined Underwater Video (UV) with eDNA metabarcoding data to produce marine fish community profiles over a 2 months period in situ at a cabled observatory in the northeast Atlantic (SmartBay Ireland). By combining both approaches, an increased number of fish could be identified to the species level (total of 22 species), including ecologically and economically important species such as Atlantic cod, whiting, mackerel and monkfish. The eDNA approach alone successfully identified a higher number of species (59%) compared to the UV approach (18%), whereby 23% of species were detected by both methods. The parallel implementation of point collection eDNA and time series UV data not only confirmed expectations of the corroborative effect of using multiple disciplines in fish community composition, but also enabled the assessment of limitations intrinsic to each technique including the identification of false-negative detections in one sampling technology relative to the other. This work showcased the usefulness of cabled observatories as key platforms for in situ empirical assessment of both challenges and prospects of novel technologies in aid to future monitoring of marine life.


Assuntos
DNA Ambiental , Animais , Código de Barras de DNA Taxonômico , Monitoramento Ambiental , Peixes/genética , Irlanda
7.
Allergol Immunopathol (Madr) ; 49(1): 113-117, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33528938

RESUMO

BACKGROUND: Spain has been severely affected by the COVID-19 epidemic, with 195,944 persons infected and 20,453 deaths at the time of writing. Older people with respiratory or cardiac conditions are most at risk. OBJECTIVE: The aim was to compare respiratory symptoms in nursing home residents and patients with uncontrolled asthma, who are considered vulnerable to COVID-19. METHODS: We studied 134 nursing home residents and 139 patients with uncontrolled asthma, groups vulnerable to COVID-19. Demographic characteristics, clinical manifestations, outcomes, key laboratory results, and radiological images were collected from medical records. COVID-19 infection was detected by polymerase chain reaction (PCR). RESULTS: Thirteen (9.3%) patients with uncontrolled asthma, all receiving inhaled corticosteroids were infected by COVID-19. Eighty (60%) nursing home residents were infected; only 28, all of whom had received inhaled corticosteroids, had a good prognosis. CONCLUSIONS: Early treatment with inhaled corticosteroids may be helpful in COVID-19 infection. Persons with an allergy might have some protective mechanisms against coronavirus.


Assuntos
Corticosteroides/uso terapêutico , Asma/tratamento farmacológico , COVID-19/prevenção & controle , Administração por Inalação , Adolescente , Corticosteroides/administração & dosagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Asma/virologia , COVID-19/diagnóstico por imagem , COVID-19/fisiopatologia , Teste de Ácido Nucleico para COVID-19 , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Casas de Saúde , Prognóstico , Espanha
8.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-20113738

RESUMO

BackgroundIn some patients the immune response triggered by SARS-CoV-2 is unbalanced, presenting an acute respiratory distress syndrome which in many cases requires intensive care unit (ICU) admission. The limitation of ICU beds has been one of the major burdens in the management worldwide; therefore, clinical strategies to avoid ICU admission are needed. ObjectiveWe aimed to describe the influence of tocilizumab on the need of transfer to ICU or death in non-critically ill patients. MethodsA retrospective study of 171 patients with SARS-CoV-2 infection that did not qualify as requiring transfer to ICU during the first 24h after admission to a conventional ward, were included. The criteria to receive tocilizumab was radiological impairment, oxygen demand or an increasing of inflammatory parameters, however, the ultimate decision was left to the attending physician judgement. The primary outcome was the need of ICU admission or death whichever came first. Results77 patients received tocilizumab and 94 did not. The tocilizumab group had less ICU admissions (10.3% vs. 27.6%, P= 0.005) and need of invasive ventilation (0 vs 13.8%, P=0.001). In multivariable analysis, tocilizumab remained as a protective variable (OR: 0.03, CI 95%: 0.007-0{middle dot}1, P=0.0001) of ICU admission or death. ConclusionTocilizumab in the early stages of the inflammatory flare, could reduce ICU admissions and mechanical ventilation use. The mortality rate of 10.3% among patients receiving tocilizumab appears to be lower than other reports. Clinical implicationOur results suggest that tocilizumab administered to non-critically ill patients could reduce ICU admissions and mortality. Capsule summaryTocilizumab administered to non-critically ill patients with SARS-CoV-2 infection in the early stages of the inflammatory flare, could reduce an important number of ICU admissions and mechanical ventilation use.

10.
Cell Chem Biol ; 26(12): 1664-1680.e4, 2019 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-31668517

RESUMO

Prion-like protein aggregation underlies the pathology of a group of fatal neurodegenerative diseases in humans, including Alzheimer's disease (AD), Parkinson's disease, amyotrophic lateral sclerosis, and transmissible spongiform encephalopathy. At present, few high-throughput screening (HTS) systems are available for anti-prion small-molecule identification. Here we describe an innovative phenotypic HTS system in yeast that allows for efficient identification of chemical compounds that eliminate the yeast prion [SWI+]. We show that some identified anti-[SWI+] compounds can destabilize other non-[SWI+] prions, and their antagonizing effects can be prion- and/or variant specific. Intriguingly, among the identified hits are several previously identified anti-PrPSc compounds and a couple of US Food and Drug Administration-approved drugs for AD treatment, validating the efficacy of this HTS system. Moreover, a few hits can reduce proteotoxicity induced by expression of several pathogenic mammalian proteins. Thus, we have established a useful HTS system for identifying compounds that can potentially antagonize prionization and human proteinopathies.


Assuntos
Ensaios de Triagem em Larga Escala/métodos , Príons/antagonistas & inibidores , Saccharomyces cerevisiae/metabolismo , Bibliotecas de Moléculas Pequenas/química , Doença de Alzheimer/tratamento farmacológico , Humanos , Lectinas de Ligação a Manose/genética , Metiltransferases/genética , Metiltransferases/metabolismo , Príons/genética , Príons/metabolismo , Regiões Promotoras Genéticas , Saccharomyces cerevisiae/crescimento & desenvolvimento , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Bibliotecas de Moléculas Pequenas/metabolismo , Bibliotecas de Moléculas Pequenas/uso terapêutico
11.
Mov Disord ; 34(2): 218-227, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30485555

RESUMO

BACKGROUND: Deep brain stimulation of the pedunculopontine nucleus has been performed to treat dopamine-resistant gait and balance disorders in patients with degenerative diseases. The outcomes, however, are variable, which may be the result of the lack of a well-defined anatomical target. OBJECTIVES: The objectives of this study were to identify the main neuronal populations of the pedunculopontine and the cuneiform nuclei that compose the human mesencephalic locomotor region and to compare their 3-dimensional distribution with those found in patients with Parkinson's disease and progressive supranuclear palsy. METHODS: We used high-field MRI, immunohistochemistry, and in situ hybridization to characterize the distribution of the different cell types, and we developed software to merge all data within a common 3-dimensional space. RESULTS: We found that cholinergic, GABAergic, and glutamatergic neurons comprised the main cell types of the mesencephalic locomotor region, with the peak densities of cholinergic and GABAergic neurons similarly located within the rostral pedunculopontine nucleus. Cholinergic and noncholinergic neuronal losses were homogeneous in the mesencephalic locomotor region of patients, with the peak density of remaining neurons at the same location as in controls. The degree of denervation of the pedunculopontine nucleus was highest in patients with progressive supranuclear palsy, followed by Parkinson's disease patients with falls. CONCLUSIONS: The peak density of cholinergic and GABAergic neurons was located similarly within the rostral pedunculopontine nucleus not only in controls but also in pathological cases. The neuronal loss was homogeneously distributed and highest in the pedunculopontine nucleus of patients with falls, which suggests a potential pathophysiological link. © 2018 International Parkinson and Movement Disorder Society.


Assuntos
Tronco Encefálico/patologia , Mesencéfalo/patologia , Doença de Parkinson/patologia , Estimulação Encefálica Profunda/métodos , Humanos , Processamento de Imagem Assistida por Computador/métodos , Neurônios/patologia , Núcleo Tegmental Pedunculopontino/patologia , Paralisia Supranuclear Progressiva/patologia
12.
J Neurol ; 263(2): 290-298, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26568561

RESUMO

Deep brain stimulation (DBS) of the internal globus pallidus (GPi) could treat chorea in Huntington's disease patients. The objectives of this study were to evaluate the efficacy of GPi-DBS to reduce abnormal movements of three patients with Huntington's disease and assess tolerability. Three non-demented patients with severe pharmacoresistant chorea underwent bilateral GPi-DBS and were followed for 30, 24, and 12 months, respectively. Primary outcome measure was the change of the chorea and total motor scores of the Unified Huntington's Disease Rating Scale between pre- and last postoperative assessments. Secondary outcome measures were motor changes between ventral versus dorsal and between on- and off- GPi-DBS. GPi neuronal activities were analyzed and compared to those obtained in patients with Parkinson's disease. No adverse effects occurred. Chorea decreased in all patients (13, 67 and 29%) postoperatively. Total motor score decreased in patient 2 (19.6%) and moderately increased in patients 1 and 3 (17.5 and 1.7%), due to increased bradykinesia and dysarthria. Ventral was superior to dorsal GPi-DBS to control chorea. Total motor score increased dramatically off-stimulation compared to ventral GPi-DBS (70, 63 and 19%). Cognitive and psychic functions were overall unchanged. Lower mean rate and less frequent bursting activity were found in Huntington's disease compared to Parkinson's disease patients. Ventral GPi-DBS sustainably reduced chorea, but worsened bradykinesia and dysarthria. Based on these results and previous published reports, we propose to select non-demented HD patients with severe chorea, and a short disease evolution as the best candidates for GPi-DBS.


Assuntos
Estimulação Encefálica Profunda/métodos , Doença de Huntington/terapia , Adulto , Feminino , Globo Pálido/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Atividade Motora , Resultado do Tratamento
13.
J Med Chem ; 56(11): 4786-97, 2013 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-23651412

RESUMO

CaV1.3 L-type calcium channels (LTCCs) have been a potential target for Parkinson's disease since calcium ion influx through the channel was implicated in the generation of mitochondrial oxidative stress, causing cell death in the dopaminergic neurons. Selective inhibition of CaV1.3 over other LTCC isoforms, especially CaV1.2, is critical to minimize potential side effects. We recently identified pyrimidinetriones (PYTs) as a CaV1.3-selective scaffold; here we report the structure-activity relationship of PYTs with both CaV1.3 and CaV1.2 LTCCs. By variation of the substituents on the cyclopentyl and arylalkyl groups of PYT, SAR studies allowed characterization of the CaV1.3 and CaV1.2 LTCCs binding sites. The SAR also identified four important moieties that either retain selectivity or enhance binding affinity. Our study represents a significant enhancement of the SAR of PYTs at CaV1.3 and CaV1.2 LTCCs and highlights several advances in the lead optimization and diversification of this family of compounds for drug development.


Assuntos
Antiparkinsonianos/síntese química , Bloqueadores dos Canais de Cálcio/síntese química , Canais de Cálcio/metabolismo , Pirimidinonas/síntese química , Antiparkinsonianos/química , Antiparkinsonianos/farmacologia , Bloqueadores dos Canais de Cálcio/química , Bloqueadores dos Canais de Cálcio/farmacologia , Canais de Cálcio/genética , Canais de Cálcio Tipo L/genética , Canais de Cálcio Tipo L/metabolismo , Células HEK293 , Ensaios de Triagem em Larga Escala , Humanos , Pirimidinonas/química , Pirimidinonas/farmacologia , Estereoisomerismo , Relação Estrutura-Atividade , Transfecção
14.
Bioorg Med Chem ; 21(14): 4365-73, 2013 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-23688558

RESUMO

The L-type calcium channel (LTCC) CaV1.3 is regarded as a new potential therapeutic target for Parkinson's disease. Calcium influx through CaV1.3 LTCC during autonomous pacemaking in adult dopaminergic neurons of the substantia nigra pars compacta is related to the generation of mitochondrial oxidative stress in animal models. Development of a CaV1.3 antagonist selective over CaV1.2 is essential because CaV1.2 pore-forming subunits are the predominant form of LTCCs and are abundant in the central nervous and cardiovascular systems. We have explored 1,4-dihydropyrimidines and 4H-pyrans to identify potent and selective antagonists of CaV1.3 relative to CaV1.2 LTCCs. A library of 36 dihydropyridine (DHP)-mimic 1,4-dihydropyrimidines and 4H-pyrans was synthesized, and promising chiral compounds were resolved. The antagonism studies of CaV1.3 and CaV1.2 LTCCs using DHP mimic compounds showed that dihydropyrimidines and 4H-pyrans are effective antagonists of DHPs for CaV1.3 LTCCs. Some 1,4-dihydropyrimidines are more selective than isradipine for CaV1.3 over CaV1.2, shown here by both calcium flux and patch-clamp electrophysiology experiments, where the ratio of antagonism is around 2-3. These results support the hypothesis that the modified hydrogen bonding donor/acceptors in DHP-mimic dihydropyrimidines and 4H-pyrans can interact differently with DHP binding sites, but, in addition, the data suggest that the binding sites of DHP in CaV1.3 and CaV1.2 LTCCs are very similar.


Assuntos
Bloqueadores dos Canais de Cálcio/síntese química , Canais de Cálcio Tipo L/química , Di-Hidropiridinas/síntese química , Mimetismo Molecular , Piranos/síntese química , Bloqueadores dos Canais de Cálcio/química , Bloqueadores dos Canais de Cálcio/farmacologia , Di-Hidropiridinas/química , Di-Hidropiridinas/farmacologia , Células HEK293 , Humanos , Concentração Inibidora 50 , Estrutura Molecular , Ligação Proteica/efeitos dos fármacos , Piranos/química , Piranos/farmacologia
15.
Mov Disord ; 26(2): 307-12, 2011 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-21412838

RESUMO

High frequency stimulation of the ventral intermedius nucleus (Vim) of the thalamus is successfully used for the treatment of postural tremor. Target coordinates are most commonly calculated using a statistical method. Here, we compare a statistical and an individual targeting method, using an histology-based three-dimensional deformable brain atlas which allows localization of the Vim on individual patient's MR images by adaptation of the atlas onto the patient's brain. Twenty-nine consecutive patients had electrodes implanted in the Vim uni-or bilaterally for severe essential tremor. Thirty-five targets were determined by calculating the statistical target and then using the deformable atlas to compute the individual target. Pythagorean distance between these targets was calculated. Statistical and individual targets were compared by double blind evaluation of perioperative stimulation effects. For most cases (n = 24), the Pythagorean distance was higher than 1.5 mm. In 79% of these cases, the definitive electrode was implanted using the position of the individual target. For the remaining cases (n = 11, distance < 1.5 mm), the definitive electrode was implanted according to the statistical target location in 73% of the cases. As a whole, when individual target was used, it was located at least 2 mm more medial than the statistical one in 86% cases. These results suggest that Vim target determination based on a statistical method might be inaccurate. In particular, laterality might be overestimated, leading to nonoptimal clinical results. In clinical practice, this means that microelectrode exploration during Vim surgery should include at least one trajectory more medial than the statistical target.


Assuntos
Tremor Essencial/terapia , Doença de Parkinson/terapia , Tálamo/cirurgia , Tremor/terapia , Adulto , Idoso , Mapeamento Encefálico , Estimulação Encefálica Profunda , Método Duplo-Cego , Eletrodos Implantados , Humanos , Pessoa de Meia-Idade , Resultado do Tratamento
16.
Bioorg Med Chem ; 18(9): 3147-58, 2010 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-20382537

RESUMO

L-type Ca(2+) channels in mammalian brain neurons have either a Ca(V)1.2 or Ca(V)1.3 pore-forming subunit. Recently, it was shown that Ca(V)1.3 Ca(2+) channels underlie autonomous pacemaking in adult dopaminergic neurons in the substantia nigra pars compacta, and this reliance renders them sensitive to toxins used to create animal models of Parkinson's disease. Antagonism of these channels with the dihydropyridine antihypertensive drug isradipine diminishes the reliance on Ca(2+) and the sensitivity of these neurons to toxins, pointing to a potential neuroprotective strategy. However, for neuroprotection without an antihypertensive side effect, selective Ca(V)1.3 channel antagonists are required. In an attempt to identify potent and selective antagonists of Ca(V)1.3 channels, 124 dihydropyridines (4-substituted-1,4-dihydropyridine-3,5-dicarboxylic diesters) were synthesized. The antagonism of heterologously expressed Ca(V)1.2 and Ca(V)1.3 channels was then tested using electrophysiological approaches and the FLIPR Calcium 4 assay. Despite the large diversity in substitution on the dihydropyridine scaffold, the most Ca(V)1.3 selectivity was only about twofold. These results support a highly similar dihydropyridine binding site at both Ca(V)1.2 and Ca(V)1.3 channels and suggests that other classes of compounds need to be identified for Ca(V)1.3 selectivity.


Assuntos
Bloqueadores dos Canais de Cálcio/síntese química , Canais de Cálcio Tipo L/efeitos dos fármacos , Canais de Cálcio/efeitos dos fármacos , Ácidos Dicarboxílicos/síntese química , Di-Hidropiridinas/síntese química , Animais , Bloqueadores dos Canais de Cálcio/química , Bloqueadores dos Canais de Cálcio/farmacologia , Linhagem Celular , Ácidos Dicarboxílicos/química , Ácidos Dicarboxílicos/farmacologia , Di-Hidropiridinas/química , Di-Hidropiridinas/farmacologia , Humanos , Concentração Inibidora 50 , Estrutura Molecular , Nifedipino/química , Nifedipino/farmacologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...