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1.
BMC Med Res Methodol ; 23(1): 265, 2023 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-37951890

RESUMO

BACKGROUND: Suboptimal or slow recruitment affects 30-50% of trials. Education and training of trial recruiters has been identified as one strategy for potentially boosting recruitment to randomised controlled trials (hereafter referred to as trials). The Training tRial recruiters, An educational INtervention (TRAIN) project was established to develop and assess the acceptability of an education and training intervention for recruiters to neonatal trials. In this paper, we report the development and acceptability of TRAIN. METHODS: TRAIN involved three sequential phases, with each phase contributing information to the subsequent phase(s). These phases were 1) evidence synthesis (systematic review of the effectiveness of training interventions and a content analysis of the format, content, and delivery of identified interventions), 2) intervention development using a Partnership (co-design/co-creation) approach, and 3) intervention acceptability assessments with recruiters to neonatal trials. RESULTS: TRAIN, accompanied by a comprehensive intervention manual, has been designed for online or in-person delivery. TRAIN can be offered to recruiters before trial recruitment begins or as refresher sessions during a trial. The intervention consists of five core learning outcomes which are addressed across three core training units. These units are the trial protocol (Unit 1, 50 min, trial-specific), understanding randomisation (Unit 2, 5 min, trial-generic) and approaching and engaging with parents (Unit 3, 70 min, trial-generic). Eleven recruiters to neonatal trials registered to attend the acceptability assessment training workshops, although only four took part. All four positively valued the training Units and resources for increasing recruiter preparedness, knowledge, and confidence. More flexibility in how the training is facilitated, however, was noted (e.g., training divided across two workshops of shorter duration). Units 2 and 3 were considered beneficial to incorporate into Good Clinical Practice Training or as part of induction training for new staff joining neonatal units. CONCLUSION: TRAIN offers a comprehensive co-produced training and education intervention for recruiters to neonatal trials. TRAIN was deemed acceptable, with minor modification, to neonatal trial recruiters. The small number of recruiters taking part in the acceptability assessment is a limitation. Scale-up of TRAIN with formal piloting and testing for effectiveness in a large cluster randomised trial is required.


Assuntos
Seleção de Pacientes , Projetos de Pesquisa , Humanos , Recém-Nascido , Ensaios Clínicos Controlados Aleatórios como Assunto
2.
Sci Immunol ; 6(64): eabb6444, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34623903

RESUMO

Interleukin-27 (IL-27) is an immunoregulatory cytokine whose essential function is to limit immune responses. We found that the gene encoding cholesterol 25-hydroxylase (Ch25h) was induced in CD4+ T cells by IL-27, enhanced by transforming growth factor­ß (TGF-ß), and antagonized by T-bet. Ch25h catalyzes cholesterol to generate 25-hydroxycholesterol (25OHC), which was subsequently released to the cellular milieu, functioning as a modulator of T cell response. Extracellular 25OHC suppressed cholesterol biosynthesis in T cells, inhibited cell growth, and induced nutrient deprivation cell death without releasing high-mobility group box 1 (HMGB1). This growth inhibitory effect was specific to actively proliferating cells with high cholesterol demand and was reversed when extracellular cholesterol was replenished. Ch25h-expressing CD4+ T cells that received IL-27 and TGF-ß signals became refractory to 25OHC-mediated growth inhibition in vitro. Nonetheless, IL-27­treated T cells negatively affected viability of bystander cells in a paracrine manner, but only if the bystander cells were in the early phases of activation. In mouse models of skin inflammation due to autoreactive T cells or chemically induced hypersensitivity, genetic deletion of Ch25h or Il27ra led to worse outcomes. Thus, Ch25h is an immunoregulatory metabolic switch induced by IL-27 and dampens excess bystander T effector expansion in tissues through its metabolite derivative, 25OHC. This study reveals regulation of cholesterol metabolism as a modality for controlling tissue inflammation and thus represents a mechanism underlying T cell immunoregulatory functions.


Assuntos
Linfócitos T CD4-Positivos/metabolismo , Mediadores da Inflamação/metabolismo , Inflamação/metabolismo , Interleucina-27/metabolismo , Pele/metabolismo , Esteroide Hidroxilases/metabolismo , Animais , Colesterol/biossíntese , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Esteroide Hidroxilases/genética
3.
Oral Oncol ; 115: 105097, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33229202

RESUMO

BACKGROUND: Tracheal stoma recurrence following oral cavity surgery is exceedingly rare. Although several different mechanisms for this have been described, the pathogenesis still remains uncertain. METHODS: We present the case of a gentleman who presented 6-months following oral cavity SCC resection with a large fungating mass at his previous tracheostomy site, and also review the reported literature on this rare phenomenon. RESULTS: Four weeks after diagnosis of his recurrence he underwent a total laryngectomy, wide-local skin excision and reconstruction with a pectoralis major pedicled flap. He recovered well initially following his operation, however unfortunately contracted nosocomial SARS-Cov2 and succumbed from respiratory complications during his post-operative recovery. CONCLUSION: Stomal recurrence after temporary tracheostomy for oral cavity malignancies are very rare. Previously reported management of these can vary from surgical to palliative treatment. Methods to prevent these include delaying tracheostomy until after surgical resection, packing the pharynx during resection and adjuvant radiotherapy.


Assuntos
Boca/cirurgia , Traqueostomia/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Boca/patologia
6.
J Hum Nutr Diet ; 30(4): 471-478, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28168753

RESUMO

BACKGROUND: Traditional methods for predicting weight loss success use regression approaches, which make the assumption that the relationships between the independent and dependent (or logit of the dependent) variable are linear. The aim of the present study was to investigate the relationship between common demographic and early weight loss variables to predict weight loss success at 12 months without making this assumption. METHODS: Data mining methods (decision trees, generalised additive models and multivariate adaptive regression splines), in addition to logistic regression, were employed to predict: (i) weight loss success (defined as ≥5%) at the end of a 12-month dietary intervention using demographic variables [body mass index (BMI), sex and age]; percentage weight loss at 1 month; and (iii) the difference between actual and predicted weight loss using an energy balance model. The methods were compared by assessing model parsimony and the area under the curve (AUC). RESULTS: The decision tree provided the most clinically useful model and had a good accuracy (AUC 0.720 95% confidence interval = 0.600-0.840). Percentage weight loss at 1 month (≥0.75%) was the strongest predictor for successful weight loss. Within those individuals losing ≥0.75%, individuals with a BMI (≥27 kg m-2 ) were more likely to be successful than those with a BMI between 25 and 27 kg m-2 . CONCLUSIONS: Data mining methods can provide a more accurate way of assessing relationships when conventional assumptions are not met. In the present study, a decision tree provided the most parsimonious model. Given that early weight loss cannot be predicted before randomisation, incorporating this information into a post randomisation trial design may give better weight loss results.


Assuntos
Mineração de Dados , Redução de Peso , Programas de Redução de Peso , Idoso , Índice de Massa Corporal , Dieta , Metabolismo Energético , Feminino , Comportamentos Relacionados com a Saúde , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade
7.
Neuron ; 90(1): 191-203, 2016 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-26996082

RESUMO

Balance of cortical excitation and inhibition (EI) is thought to be disrupted in several neuropsychiatric conditions, yet it is not clear how it is maintained in the healthy human brain. When EI balance is disturbed during learning and memory in animal models, it can be restabilized via formation of inhibitory replicas of newly formed excitatory connections. Here we assess evidence for such selective inhibitory rebalancing in humans. Using fMRI repetition suppression we measure newly formed cortical associations in the human brain. We show that expression of these associations reduces over time despite persistence in behavior, consistent with inhibitory rebalancing. To test this, we modulated excitation/inhibition balance with transcranial direct current stimulation (tDCS). Using ultra-high-field (7T) MRI and spectroscopy, we show that reducing GABA allows cortical associations to be re-expressed. This suggests that in humans associative memories are stored in balanced excitatory-inhibitory ensembles that lie dormant unless latent inhibitory connections are unmasked.


Assuntos
Córtex Cerebral/fisiologia , Memória/fisiologia , Inibição Neural/fisiologia , Associação , Córtex Cerebral/metabolismo , Feminino , Neuroimagem Funcional , Humanos , Aprendizagem/fisiologia , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Masculino , Vias Neurais , Estimulação Transcraniana por Corrente Contínua , Adulto Jovem , Ácido gama-Aminobutírico/metabolismo
8.
Ann Clin Biochem ; 53(Pt 1): 150-4, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25766384

RESUMO

BACKGROUND: Diagnosis of subarachnoid haemorrhage, a neurosurgical emergency in patients with headache remains a logistical challenge. The rationale of the traditional pathway of cerebrospinal fluid xanthochromia analysis following negative computed tomography head scans to exclude subarachnoid haemorrhage has been challenged by the increasing accuracy of modern computed tomography scanners. AIM: We set out to establish whether our xanthochromia service was adding value to the diagnostic pathway for subarachnoid haemorrhage or whether it was acting merely as a supportive test. METHOD: A retrospective audit of all cerebrospinal fluid requests received since the inception of Xanthochromia service at a tertiary trauma centre. Cases interpreted as being consistent with subarachnoid haemorrhage based on cerebrospinal fluid xanthochromia analysis were selected for in-depth review from the total number of cases. RESULTS: In total 660 requests were received for cerebrospinal fluid xanthochromia between August 2009 and July 2012. A total 28 of these were interpreted as being consistent with subarachnoid haemorrhage. Only 18 (64.3%) of requests were deemed appropriate as the clinical presentation in the remaining 10 (35.7%) was strongly suggestive of other causes of headache. A final clinical diagnosis of subarachnoid haemorrhage was made in 11 of the 18 patients who had cerebrospinal fluid xanthochromia requested appropriately. From these 11, five (45%) were deemed initially computed tomography negative and cerebrospinal fluid analysis led to final correct diagnosis of subarachnoid haemorrhage and appropriate surgical management. CONCLUSION: Despite improved computed tomography scanning technology, cerebrospinal fluid xanthochromia interpretation aids in the definitive diagnosis of subarachnoid haemorrhage. When requested appropriately cerebrospinal fluid xanthochromia analysis remains a vital service as results impact on clinical decision making, especially when computed tomography scan results are equivocal and is also important in later presenting patients when computed tomography accuracy decreases.


Assuntos
Encaminhamento e Consulta , Hemorragia Subaracnóidea/líquido cefalorraquidiano , Hemorragia Subaracnóidea/diagnóstico por imagem , Centros de Atenção Terciária , Tomografia Computadorizada por Raios X , Centros de Traumatologia , Auditoria Clínica , Humanos , Estudos Retrospectivos
9.
Eur J Clin Nutr ; 68(7): 778-85, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24667750

RESUMO

BACKGROUND/OBJECTIVES: Direct evidence for the effects of vegetable intake on weight loss is qualified. The study aimed to assess the effect of higher vegetable consumption on weight loss. SUBJECTS/METHODS: A single blind parallel controlled trial was conducted with 120 overweight adults (mean body mass index=29.98 kg/m(2)) randomised to two energy deficit healthy diet advice groups differing only by doubling the serving (portion) sizes of vegetables in the comparator group. Data were analysed as intention-to-treat using a linear mixed model. Spearmans rho bivariate was used to explore relationships between percentage energy from vegetables and weight loss. RESULTS: After 12 months, the study sample lost 6.5±5.2 kg (P<0.001 time) with no difference between groups (P>0.05 interaction). Both groups increased vegetable intake and lost weight in the first 3 months, and the change in weight was significantly correlated with higher proportions of energy consumed as vegetables (rho=-0.217, P=0.024). Fasting glucose, insulin and triglyceride levels decreased (P<0.001 time) and high-density lipoprotein cholesterol levels increased (P<0.001 time), with no difference between groups. Weight loss was sustained for 12 months by both groups, but the comparator group reported greater hunger satisfaction (P=0.005). CONCLUSIONS: Advice to consume a healthy low-energy diet leads to sustained weight loss, with reductions in cardiovascular disease risk factors regardless of an emphasis on more vegetables. In the short term, consuming a higher proportion of the dietary energy as vegetables may support a greater weight loss and the dietary pattern appears sustainable.


Assuntos
Restrição Calórica , Dieta Redutora , Obesidade/dietoterapia , Verduras , Redução de Peso , Adulto , Glicemia/metabolismo , Índice de Massa Corporal , HDL-Colesterol/sangue , Ingestão de Energia , Feminino , Humanos , Fome , Insulina/sangue , Análise de Intenção de Tratamento , Masculino , Obesidade/sangue , Sobrepeso , Tamanho da Porção , Saciação , Método Simples-Cego , Triglicerídeos/sangue
10.
J Hum Nutr Diet ; 27(4): 401-10, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24118282

RESUMO

BACKGROUND: Wellness and wellbeing are terms associated with health within dietetic discourse. More broadly, these terms are found in social discourse as represented in food and nutrition consumer communications. With the increasing requirement for evidence-based healthcare, there is an imperative to understand whether these terms are meaningful to individuals typically targeted for nutrition interventions and whether there are any implications for dietetic education. METHODS: To explore the understanding of these terms, eight semi-structured focus groups were conducted with 32 female participants (age range 23-79 years) who were actively engaged in managing their health. Overall understanding of the terms, factors that impacted perceptions and any relationships with food behaviour were investigated with the groups. Group discussions were transcribed verbatim and each transcript was examined by two researchers. Inductive analysis linking codes into main thematic categories was conducted using the constant comparison approach across the full data set. RESULTS: Wellness and wellbeing were identified as meaningful terms associated with health. A theoretical framework of wellness and wellbeing reflecting these meanings was developed linking four dominant thematic areas. These were Desired outcomes (most sought after result); Taking control (self management strategies); Internal influences (various personal inner factors influencing behaviours); and External influences (plethora of peripheral factors influencing behaviours). CONCLUSIONS: Wellness and wellbeing are terms that are relevant and aspirational for individuals typically targeted for nutrition intervention. A theoretical framework of dominant areas of influence on notions of wellness and wellbeing was identified. This theoretical framework is worthy of further research to determine usefulness and effectiveness in dietetic practice settings.


Assuntos
Comportamento Alimentar , Comportamentos Relacionados com a Saúde , Conhecimentos, Atitudes e Prática em Saúde , Satisfação Pessoal , Adulto , Idoso , Comunicação , Dieta , Feminino , Grupos Focais , Humanos , Estilo de Vida , Pessoa de Meia-Idade , Atividade Motora , Estado Nutricional , Pesquisa Qualitativa , Resultado do Tratamento , Adulto Jovem
11.
AJNR Am J Neuroradiol ; 34(1): E5-7, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21778242

RESUMO

Two of the most common reasons for failure to obtain adequate preoperative functional data are inadequate task performance and excessive head motion. With an MR imaging-compatible pneumatically driven manipulandum, passive motor tasks elicited reproducible contralateral activation in the M1 and S1 in 10 healthy controls and 6 patients. The SMA was localized in all healthy controls and in 5 of 6 patients. Head motion was reduced in passive tasks compared with active tasks.


Assuntos
Mapeamento Encefálico/instrumentação , Encéfalo/fisiopatologia , Potencial Evocado Motor , Potenciais Somatossensoriais Evocados , Dedos/fisiologia , Imageamento por Ressonância Magnética/instrumentação , Estimulação Física/instrumentação , Adulto , Desenho de Equipamento , Análise de Falha de Equipamento , Feminino , Humanos , Masculino , Cuidados Pré-Operatórios/instrumentação , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
13.
J Am Coll Cardiol ; 57(2): 138-46, 2011 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-21211684

RESUMO

OBJECTIVES: The purpose of this study was to examine the association between lower socioeconomic status (SES), as ascertained by years of education, and outcomes in patients with acute ST-segment elevation myocardial infarction (STEMI). BACKGROUND: Previous studies have shown an inverse relationship between SES and coronary heart disease and mortality. Whether a similar association between SES and mortality exists in STEMI patients is unknown. METHODS: We evaluated 11,326 patients with STEMI in the GUSTO-III (Global Use of Strategies to Open Occluded Coronary Arteries) trial study from countries that enrolled >500 patients. We evaluated clinical outcomes (adjusted using multivariate regression analysis) according to the number of years of education completed. RESULTS: One-year mortality was inversely related to years of education and was 5-fold higher in patients with <8 years compared with those with >16 years of education (17.5% vs. 3.5%, p < 0.0001). The strength of the relationship between education and mortality varied among different countries. Nonetheless, years of education remained an independent correlate of mortality at day 7 (hazard ratio per year of increase in education: 0.86; 95% confidence interval: 0.83 to 0.88) and also between day 8 and 1 year (hazard ratio per year of increase in education: 0.96; 95% confidence interval: 0.94 to 0.98), even after adjustment for baseline characteristics and country of enrollment. CONCLUSIONS: When the number of years of education was used as a measure of SES, there was an inverse relationship such that significantly higher short-term and 1-year mortality existed beyond that accounted for by baseline clinical variables and country of enrollment. Future studies should account for and investigate the mechanisms underlying this link between SES and cardiovascular disease outcomes.


Assuntos
Eletrocardiografia , Fibrinolíticos/uso terapêutico , Infarto do Miocárdio/mortalidade , Educação de Pacientes como Assunto/métodos , Terapia Trombolítica/métodos , Idoso , Alberta/epidemiologia , Feminino , Seguimentos , Humanos , Irlanda/epidemiologia , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/tratamento farmacológico , Infarto do Miocárdio/fisiopatologia , Nova Zelândia/epidemiologia , Estudos Retrospectivos , Taxa de Sobrevida/tendências , Fatores de Tempo , Estados Unidos/epidemiologia
15.
Brain ; 133(Pt 3): 895-908, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20110244

RESUMO

Unilateral neglect is a disabling syndrome frequently observed following right hemisphere brain damage. Symptoms range from visuo-motor impairments through to deficient visuo-spatial imagery, but impairment can also affect the auditory modality. A short period of adaptation to a rightward prismatic shift of the visual field is known to improve a wide range of hemispatial neglect symptoms, including visuo-manual tasks, mental imagery, postural imbalance, visuo-verbal measures and number bisection. The aim of the present study was to assess whether the beneficial effects of prism adaptation may generalize to auditory manifestations of neglect. Auditory extinction, whose clinical manifestations are independent of the sensory modalities engaged in visuo-manual adaptation, was examined in neglect patients before and after prism adaptation. Two separate groups of neglect patients (all of whom exhibited left auditory extinction) underwent prism adaptation: one group (n = 6) received a classical prism treatment ('Prism' group), the other group (n = 6) was submitted to the same procedure, but wore neutral glasses creating no optical shift (placebo 'Control' group). Auditory extinction was assessed by means of a dichotic listening task performed three times: prior to prism exposure (pre-test), upon prism removal (0 h post-test) and 2 h later (2 h post-test). The total number of correct responses, the lateralization index (detection asymmetry between the two ears) and the number of left-right fusion errors were analysed. Our results demonstrate that prism adaptation can improve left auditory extinction, thus revealing transfer of benefit to a sensory modality that is orthogonal to the visual, proprioceptive and motor modalities directly implicated in the visuo-motor adaptive process. The observed benefit was specific to the detection asymmetry between the two ears and did not affect the total number of responses. This indicates a specific effect of prism adaptation on lateralized processes rather than on general arousal. Our results suggest that the effects of prism adaptation can extend to unexposed sensory systems. The bottom-up approach of visuo-motor adaptation appears to interact with higher order brain functions related to multisensory integration and can have beneficial effects on sensory processing in different modalities. These findings should stimulate the development of therapeutic approaches aimed at bypassing the affected sensory processing modality by adapting other sensory modalities.


Assuntos
Adaptação Psicológica , Percepção Auditiva , Lateralidade Funcional , Transtornos da Percepção , Percepção Visual , Estimulação Acústica , Adulto , Lesões Encefálicas/complicações , Lesões Encefálicas/diagnóstico por imagem , Lesões Encefálicas/patologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Transtornos da Percepção/diagnóstico por imagem , Transtornos da Percepção/etiologia , Transtornos da Percepção/patologia , Estimulação Luminosa , Psicoacústica , Percepção Espacial , Análise e Desempenho de Tarefas , Fatores de Tempo , Tomografia Computadorizada por Raios X , Adulto Jovem
16.
Circ Cardiovasc Interv ; 2(1): 43-51, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20031692

RESUMO

BACKGROUND: Only limited data describe relationships between stent parameters (length and diameter), adverse events after percutaneous coronary intervention, and effects of platelet glycoprotein IIb/IIIa blockade by stent parameters. METHODS AND RESULTS: In this post hoc analysis of the 1983 patients receiving a stent in the Enhanced Suppression of the Platelet Glycoprotein IIb/IIIa Receptor with Integrilin Therapy randomized percutaneous coronary intervention trial of eptifibatide versus placebo, rates of the major adverse cardiac event (MACE) end point (death, myocardial infarction, urgent target-vessel revascularization, or thrombotic bailout) at 48 hours and 1 year were correlated with stent parameters and then analyzed by randomization to eptifibatide versus placebo. In the placebo group, MACE increased with number of stents implanted, total stent length (by quartiles of <15, 15 to <18, 18 to <30, and >or=30 mm), and total stented vessel area (by quartiles of area <141, 141 to <188, 188 to <292, and >or=292 mm(2)). By stent parameters, MACE at 48 hours was reduced in the eptifibatide group at stent lengths of 18 to <30 mm (odds ratio [OR], 0.55; 95% CI, 0.32 to 0.94; P=0.030) and >or=30 mm (OR, 0.43; 95% CI, 0.25 to 0.75; P=0.003), stent diameters of >2.5 to <3.5 mm (OR, 0.56; 95% CI, 0.39 to 0.82; P=0.002), and with 2 stents implanted (OR, 0.39; 95% CI, 0.22 to 0.69; P=0.001). In the placebo group, near-linear relationships were observed between both increasing stent length and increasing stented vessel area and MACE at 48 hours and 1 year (all, P<0.001); these gradients were flattened in the eptifibatide group (P=0.005 for stent length). CONCLUSIONS: Stent parameters predict MACE after percutaneous coronary intervention. Glycoprotein IIb/IIIa blockade mitigates much of the hazard of increasing procedural complexity.


Assuntos
Angioplastia Coronária com Balão/instrumentação , Doença da Artéria Coronariana/terapia , Peptídeos/uso terapêutico , Inibidores da Agregação Plaquetária/uso terapêutico , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/antagonistas & inibidores , Stents , Idoso , Angioplastia Coronária com Balão/efeitos adversos , Angioplastia Coronária com Balão/mortalidade , Doença da Artéria Coronariana/tratamento farmacológico , Doença da Artéria Coronariana/mortalidade , Método Duplo-Cego , Eptifibatida , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/etiologia , Infarto do Miocárdio/prevenção & controle , Razão de Chances , Peptídeos/efeitos adversos , Inibidores da Agregação Plaquetária/efeitos adversos , Desenho de Prótese , Medição de Risco , Fatores de Risco , Trombose/etiologia , Trombose/prevenção & controle , Resultado do Tratamento
17.
Eur J Neurosci ; 30(7): 1412-23, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19788568

RESUMO

Transcranial direct current stimulation (tDCS) is currently attracting increasing interest as a tool for neurorehabilitation. However, local and distant effects of tDCS on motor-related cortical activation patterns remain poorly defined, limiting the rationale for its use. Here we describe the results of a functional magnetic resonance imaging (MRI) experiment designed to characterize local and distant effects on cortical motor activity following excitatory anodal stimulation and inhibitory cathodal stimulation. Fifteen right-handed subjects performed a visually cued serial reaction time task with their right hand in a 3-T MRI scanner both before and after 10 min of 1-mA tDCS applied to the left primary motor cortex (M1). Relative to sham stimulation, anodal tDCS led to short-lived activation increases in the M1 and the supplementary motor area (SMA) within the stimulated hemisphere. The increase in activation in the SMA with anodal stimulation was found also when directly comparing anodal with cathodal stimulation. Relative to sham stimulation, cathodal tDCS led to an increase in activation in the contralateral M1 and dorsal premotor cortex (PMd), as well as an increase in functional connectivity between these areas and the stimulated left M1. These increases were also found when directly comparing cathodal with anodal stimulation. Significant within-session linear decreases in activation occurred in all scan sessions. The after-effects of anodal tDCS arose primarily from a change in the slope of these decreases. In addition, following sham stimulation compared with baseline, a between-session decrease in task-related activity was found. The effects of cathodal tDCS arose primarily from a reduction of this normal decrease.


Assuntos
Lobo Frontal/fisiologia , Atividade Motora/fisiologia , Córtex Motor/fisiologia , Adulto , Encéfalo/fisiologia , Mapeamento Encefálico , Sinais (Psicologia) , Estimulação Elétrica , Eletromiografia , Potencial Evocado Motor , Feminino , Lateralidade Funcional , Humanos , Modelos Lineares , Imageamento por Ressonância Magnética , Masculino , Vias Neurais/fisiologia , Testes Neuropsicológicos , Estimulação Magnética Transcraniana , Adulto Jovem
18.
Can J Cardiol ; 25(8): e269-72, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19668787

RESUMO

BACKGROUND: The Enhanced Suppression of the Platelet glycoprotein IIb/IIIa Receptor with Integrilin Therapy (ESPRIT) trial compared the use of eptifibatide with placebo in 2064 coronary intervention patients. It was previously reported that Canadian patients had reduced rates of 30-day and one-year death, myocardial infarction (MI) or target vessel revascularization (TVR) compared with patients in the United States (US). OBJECTIVE: To examine whether operator or institutional volume differences explain the regional variation in clinical outcome. METHODS AND RESULTS: Each site received an operator and institutional volume survey. Fifty-seven sites (62%) returned complete data on 1338 patients. In this smaller cohort, Canadian patients had reduced rates of 30-day and one-year death, MI or TVR compared with US patients (6.3% versus 10.3% and 14.9% versus 20.1%, respectively; P<0.05 for both comparisons). Among 176 physicians with a median of 13 years experience, the median operator volume was 200 cases per year. Operators with fewer than 100 cases per year had higher rates of 30-day death, MI or TVR (13.2% versus 8.7%; P=0.18) and large MI (7.7% versus 3.3%; P=0.06) than those with 100 or more cases per year. The median institutional volume was 1064 cases per year. Canadian and US centres had similar operator and institutional volumes. By multivariate modelling, operator volume was not predictive of adverse clinical events. However, the rates of 30-day and one-year death, MI or TVR fell by 3% for every 100 patients treated by the institution (OR 0.97; P=0.058 and P=0.002, respectively). Enrollment in Canada was associated with improved outcomes at 30 days (OR 0.50; P=0.001) and one year (OR 0.66; P=0.001) despite inclusion of volume variables in the models. CONCLUSIONS: In the ESPRIT study, institutional volume was associated with a modest reduction in risk of death, MI or TVR over short- and long-term follow-up periods. The Canadian and US investigators and institutions selected in ESPRIT had similar annual procedural volumes. Therefore, volume variables did not explain the differential risk of clinical events observed for patients enrolled in the two countries.


Assuntos
Angioplastia Coronária com Balão/efeitos adversos , Angioplastia Coronária com Balão/estatística & dados numéricos , Doença da Artéria Coronariana/terapia , Adulto , Canadá , Eptifibatida , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Peptídeos/uso terapêutico , Inibidores da Agregação Plaquetária/uso terapêutico , Fatores de Risco , Resultado do Tratamento , Estados Unidos
19.
Mucosal Immunol ; 1(4): 279-88, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19079189

RESUMO

Loss of CD4(+) T cells in the gut is necessary but not sufficient to cause AIDS in animal models, raising the possibility that a differential loss of CD4(+) T-cell subtypes may be important. We found that CD4(+) T cells that produce interleukin (IL)-17, a recently identified lineage of effector CD4(+) T-helper cells, are infected by SIV(mac251)in vitro and in vivo, and are found at lower frequency at mucosal and systemic sites within a few weeks from infection. In highly viremic animals, Th1 cells predominates over Th17 T cells and the frequency of Th17 cells at mucosal sites is negatively correlated with plasma virus level. Because Th17 cells play a central role in innate and adaptive immune response to extracellular bacteria, our finding may explain the chronic enteropathy in human immunodeficiency virus (HIV) infection. Thus, therapeutic approaches that reconstitute an adequate balance between Th1 and Th17 may be beneficial in the treatment of HIV infection.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Interleucina-17/imunologia , Mucosa/imunologia , Síndrome de Imunodeficiência Adquirida dos Símios/imunologia , Vírus da Imunodeficiência Símia/fisiologia , Células Th1/imunologia , Animais , Antígenos Virais/imunologia , Humanos , Linfócitos/imunologia , Macaca mulatta , Mucosa/virologia , Síndrome de Imunodeficiência Adquirida dos Símios/virologia , Vírus da Imunodeficiência Símia/imunologia , Replicação Viral/fisiologia
20.
Br J Ophthalmol ; 92(6): 832-8, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18523088

RESUMO

BACKGROUND/AIMS: Photoreceptor-specific upregulation of vascular endothelial growth factor (VEGF) in a transgenic mouse model (Kimba) of retinal neovascularisation induces retinal vascular damage which appears similar to that in diabetic retinopathy. Here we have determined whether the choroidal vasculature is also affected in Kimba. METHODS: Kimba mice were assessed with fundus fluorescein angiography for mild, moderate or severe retinal vascular leakage prior to preparation of choroidal corrosion casts for quantitative analysis using scanning electron microscopy. VEGF was located immunohistochemically. RESULTS: Choroidal abnormalities included microaneurysms, constriction, shrinkage and dropout in the capillaries and tortuosity and loops in the arteries and veins which were similar to those observed in corrosion casts of the human choroid in diabetes. Similar to human diabetes, choroidal neovascularisation was not observed. The severity of choroidal damage correlated with the extent of retinal vascular leakage. In addition to the expected presence of VEGF in photoreceptors, VEGF was also detected in the pigment epithelium and choroid in the transgenic mice. CONCLUSION: We show that elevated retinal VEGF levels trigger pathophysiological changes in the choroid. We suggest that therapies to prevent vascular damage in diabetes must target both the retinal and choroidal vasculatures.


Assuntos
Corioide/irrigação sanguínea , Neovascularização Retiniana/patologia , Fator A de Crescimento do Endotélio Vascular/genética , Animais , Capilares/ultraestrutura , Corioide/química , Corioide/metabolismo , Molde por Corrosão , Angiofluoresceinografia , Fundo de Olho , Camundongos , Camundongos Transgênicos , Microscopia Eletrônica de Varredura , Modelos Animais , Fenótipo , Epitélio Pigmentado Ocular/química , Epitélio Pigmentado Ocular/metabolismo , Neovascularização Retiniana/metabolismo , Fator A de Crescimento do Endotélio Vascular/análise , Fator A de Crescimento do Endotélio Vascular/metabolismo
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