Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99


Any time

2019 ( 9 )

2018 ( 17 )

2017 ( 13 )

2016 ( 18 )

Custom range...

Search Results: 1 - 10 of 7021 matches for " Felipe Fregni "
All listed articles are free for downloading (OA Articles)
Page 1 /7021
Display every page Item
Limits to clinical trials in surgical areas
Demange, Marco Kawamura;Fregni, Felipe;
Clinics , 2011, DOI: 10.1590/S1807-59322011000100027
Abstract: randomized clinical trials are considered to be the gold standard of evidence-based medicine nowadays. however, it is important that we point out some limitations of randomized clinical trials relating to surgical interventions. there are limitations that affect the external and internal validity of many surgical study designs. some limitations can be bypassed, but can make it more difficult for the study to be carried out. other limitations cannot be bypassed. when it is intended to extrapolate the result of a randomized clinical trial, the premise is that the performed or to be performed intervention will be similar wherever applied and/or for every doctor using it. however, no matter how standardized the technique may be, the results are not similar for all surgeons, which implies a significant limitation to surgical randomized clinical trials concerning external validity. when considering the various limitations presented for performing surgical trials capable of generating scientific evidence within the patterns currently proposed in the evidence level classifications of medical publications, it is necessary to rethink whether those scientific evidence levels are similarly applicable to surgical works and to nonsurgical trials. we currently live in a time of supposed ''inferiority'' of surgical scientific works under the optics of the current quality criteria for a ''suitable'' clinical trial
O retorno da estimula??o cerebral na terapêutica dos transtornos neuropsiquiátricos: o papel da estimula??o magnética transcraniana na prática clínica
Fregni, Felipe;Marcolin, Marco Antonio;
Revista de Psiquiatria Clínica , 2004, DOI: 10.1590/S0101-60832004000500005
Abstract: transcranial magnetic stimulation (tms) is a new technique capable of stimulating the brain with some advantages over existing ones. tms is painless, non-invasive, simple to apply and, more importantly, it is considered of low risk for research in human. this new tool has been proposed to be used in several neurologic and psychiatric diseases. the mechanism of tms action might be based on the modulation of cortical brain excitability. therefore, brain disorders with cortical excitability dysfunction such as epilepsy, stroke, distonia, parkinson disease, depression and schizophrenia may be benefited from this method. some of these disorders have been extensively studied during the last decade - such as depression - but the results to date are still not strong enough to prove the real clinical benefit of this technique. tms is still experimental and more work is needed, but in the future, tms may become a major therapeutic tool in neuropsychiatry. the objective of the authors in this article is to review the basic principles of tms and discuss the results of published studies about the clinical applications of tms.
Changes in Clinical Trials Methodology Over Time: A Systematic Review of Six Decades of Research in Psychopharmacology
André R. Brunoni,Laura Tadini,Felipe Fregni
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0009479
Abstract: There have been many changes in clinical trials methodology since the introduction of lithium and the beginning of the modern era of psychopharmacology in 1949. The nature and importance of these changes have not been fully addressed to date. As methodological flaws in trials can lead to false-negative or false-positive results, the objective of our study was to evaluate the impact of methodological changes in psychopharmacology clinical research over the past 60 years.
Transcranial Direct Current Stimulation Reduces Negative Affect but Not Cigarette Craving in Overnight Abstinent Smokers
Jiansong Xu,Felipe Fregni,Ardeshir S. Rahman
Frontiers in Psychiatry , 2013, DOI: 10.3389/fpsyt.2013.00112
Abstract: Transcranial direct current stimulation (tDCS) can enhance cognitive control functions including attention and top-down regulation over negative affect and substance craving in both healthy and clinical populations, including early abstinent (~1.5 h) smokers. The aim of this study was to assess whether tDCS modulates negative affect, cigarette craving, and attention of overnight abstinent tobacco dependent smokers. In this study, 24 smokers received a real and a sham session of tDCS after overnight abstinence from smoking on two different days. We applied anode to the left dorsolateral prefrontal cortex and cathode to the right supra-orbital area for 20 min with a current of 2.0 mA. We used self-report questionnaires Profile of Mood States (POMS) to assess negative affect and Urge to Smoke (UTS) Scale to assess craving for cigarette smoking, and a computerized visual target identification task to assess attention immediately before and after each tDCS. Smokers reported significantly greater reductions in POMS scores of total mood disturbance and scores of tension–anxiety, depression–dejection, and confusion–bewilderment subscales after real relative to sham tDCS. Furthermore, this reduction in negative affect positively correlated with the level of nicotine dependence as assessed by Fagerstr?m scale. However, reductions in cigarette craving after real vs. sham tDCS did not differ, nor were there differences in reaction time or hit rate change on the visual task. Smokers did not report significant side effects of tDCS. This study demonstrates the safety of tDCS and its promising effect in ameliorating negative affect in overnight abstinent smokers. Its efficacy in treating tobacco dependence deserves further investigation.
Placebo Response of Non-Pharmacological and Pharmacological Trials in Major Depression: A Systematic Review and Meta-Analysis
André Russowsky Brunoni, Mariana Lopes, Ted J. Kaptchuk, Felipe Fregni
PLOS ONE , 2009, DOI: 10.1371/journal.pone.0004824
Abstract: Background Although meta-analyses have shown that placebo responses are large in Major Depressive Disorder (MDD) trials; the placebo response of devices such as repetitive transcranial magnetic stimulation (rTMS) has not been systematically assessed. We proposed to assess placebo responses in two categories of MDD trials: pharmacological (antidepressant drugs) and non-pharmacological (device- rTMS) trials. Methodology/Principal Findings We performed a systematic review and meta-analysis of the literature from April 2002 to April 2008, searching MEDLINE, Cochrane, Scielo and CRISP electronic databases and reference lists from retrieved studies and conference abstracts. We used the keywords placebo and depression and escitalopram for pharmacological studies; and transcranial magnetic stimulation and depression and sham for non-pharmacological studies. All randomized, double-blinded, placebo-controlled, parallel articles on major depressive disorder were included. Forty-one studies met our inclusion criteria - 29 in the rTMS arm and 12 in the escitalopram arm. We extracted the mean and standard values of depression scores in the placebo group of each study. Then, we calculated the pooled effect size for escitalopram and rTMS arm separately, using Cohen's d as the measure of effect size. We found that placebo response are large for both escitalopram (Cohen's d - random-effects model - 1.48; 95%C.I. 1.26 to 1.6) and rTMS studies (0.82; 95%C.I. 0.63 to 1). Exploratory analyses show that sham response is associated with refractoriness and with the use of rTMS as an add-on therapy, but not with age, gender and sham method utilized. Conclusions/Significance We confirmed that placebo response in MDD is large regardless of the intervention and is associated with depression refractoriness and treatment combination (add-on rTMS studies). The magnitude of the placebo response seems to be related with study population and study design rather than the intervention itself.
Task-Specific Effects of tDCS-Induced Cortical Excitability Changes on Cognitive and Motor Sequence Set Shifting Performance
Jorge Leite, Sandra Carvalho, Felipe Fregni, óscar F. Gon?alves
PLOS ONE , 2011, DOI: 10.1371/journal.pone.0024140
Abstract: In this study, we tested the effects of transcranial Direct Current Stimulation (tDCS) on two set shifting tasks. Set shifting ability is defined as the capacity to switch between mental sets or actions and requires the activation of a distributed neural network. Thirty healthy subjects (fifteen per site) received anodal, cathodal and sham stimulation of the dorsolateral prefrontal cortex (DLPFC) or the primary motor cortex (M1). We measured set shifting in both cognitive and motor tasks. The results show that both anodal and cathodal single session tDCS can modulate cognitive and motor tasks. However, an interaction was found between task and type of stimulation as anodal tDCS of DLPFC and M1 was found to increase performance in the cognitive task, while cathodal tDCS of DLPFC and M1 had the opposite effect on the motor task. Additionally, tDCS effects seem to be most evident on the speed of changing sets, rather than on reducing the number of errors or increasing the efficacy of irrelevant set filtering.
Using non-invasive brain stimulation to augment motor training-induced plasticity
Nadia Bolognini, Alvaro Pascual-Leone, Felipe Fregni
Journal of NeuroEngineering and Rehabilitation , 2009, DOI: 10.1186/1743-0003-6-8
Abstract: Motor impairments following stroke or traumatic brain injury (TBI) are the leading cause of disability in adults. More than 69% of all stroke survivors experience lasting functional motor impairments in the upper limbs and approximately 56% continue to complain of marked hemiparesis as long as 5 years post-stroke [1-5]. Such losses in function can severely impact quality of life and the functional independence in numerous activities of daily living [4,5]. Similarly, after TBI, fine and gross motor deficits are frequently observed. Complementary impairments such as ataxia, movement disorders and vestibular impairments, can also potentially affect motor functioning in TBI. Moreover, other factors such as multiple trauma, resulting in musculo-skeletal and peripheral nervous system injury, also complicate the recovery of motor functions in these patients [6].Although some degree of recovery may occur spontaneously, there is strong evidence that intensive practice is essential in order to substantially promote motor recovery [7-9]. As shown by several neurobehavioral discoveries in animals and humans, such experience-dependent change can occur at multiple levels of the central nervous system, from the molecular, to the synaptic level of cortical maps and large-scale neural networks [10,11].Standard motor therapies involve different approaches aimed at improving motor functions by minimising impairment or developing suitable adaptation strategies. For instance, neurofacilitation techniques are aimed at retraining motor control by promoting normal (recruitment of paretic muscles) while discouraging abnormal movement or muscle tone. Different facilitation approaches have been developed, including cutaneous/proprioceptive, weight bearing, proximal pre-innervation, and contralateral pre-innervation [12]. Task-specific training is aimed at improving skill in performing selected movement or functional tasks: examples of this type of treatment are index finger tracking [13] or t
Uma janela terapêutica para a estimula??o magnética transcraniana na epilepsia refratária
Fregni, Felipe;Pascual-Leone, Alvaro;Valente, Kette D. R.;
Journal of Epilepsy and Clinical Neurophysiology , 2005, DOI: 10.1590/S1676-26492005000400005
Abstract: objective: epilepsy is determined by an altered balance between excitatory and inhibitory influences at the cortical level. therefore, methods that can restablish this normal balance are warranted to improve epilepsy treatment. transcranial magnetic stimulation (tms) is a noninvasive procedure that can modulate the cortical excitability. this review analyzes the current role of tms in the treatment of refractory epilepsy. methods: medline was used as a database to review pertinent articles and abstracts. results: treatment with rtms (repetitive tms) in patients with refractory epilepsy is safe and may benefit patients without surgical indication. although there are few randomized studies with homogeneous groups of patients, there are evidences that patients with neocortical lesions will have more benefits from this technique than those with mesial lesions, which may represent a limitation of this non-invasive procedure. conclusion: tms may represent an important therapeutic tool for patients with refractory epilepsy without surgical indication, especially those with neocortical lesions, as it is non-invasive and safe treatment.
Afasia global sem hemiparesia: AVC ou transtorno conversivo?
Negreiros, Daniel Philippi de;Fregni, Felipe;Scalco, Andréia Zavaloni;
Revista de Psiquiatria Clínica , 2007, DOI: 10.1590/S0101-60832007000100004
Abstract: background: the neurologic and psychiatric diagnosis in emergency settings are difficult tasks and require interdisciplinary effort. conversion disorder is one of the differential diagnosis for certain neurologic disorders. the main characteristic is motor or sensory deficits suggesting neurologic or medical condition, but without organic disease that explains the symptoms. case report: we present a 23 year-old-woman with an atypical clinical presentation of stroke: global aphasia without hemiparesis. this patient was initially diagnosed with conversion disorder by the internal medicine service in the emergency room. conclusion: some rare neurologic diseases can be interpreted as conversive disorders due to some reasons: clinical similarities between the two disorders, unusual clinical presentations, comorbidity of neurologic and psychiatric disorders and psychological features of the neurological patients. patients presenting with atypical neurological or psychiatric symptoms, in which a diagnosis of conversion disorder is suspected, should always be investigated in an interdisciplinary setting.
Pharmacological and combined interventions for the acute depressive episode: focus on efficacy and tolerability
Andre R Brunoni, Renerio Fraguas Jr, Felipe Fregni
Therapeutics and Clinical Risk Management , 2009, DOI: http://dx.doi.org/10.2147/TCRM.S5751
Abstract: rmacological and combined interventions for the acute depressive episode: focus on efficacy and tolerability Review (3868) Total Article Views Authors: Andre R Brunoni, Renerio Fraguas Jr, Felipe Fregni Published Date November 2009 Volume 2009:5 Pages 897 - 910 DOI: http://dx.doi.org/10.2147/TCRM.S5751 Andre R Brunoni1, Renerio Fraguas Jr1, Felipe Fregni2 1Department and Institute of Psychiatry, University of Sao Paulo, Brazil; 2Laboratory of Neuromodulation, Spaulding Rehabilitation Center, Harvard Medical School and Berenson-Allen Center for Noninvasive Brain Stimulation, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, USA Background: Use of antidepressants is the gold standard therapy for major depression. However, despite the large number of commercially available antidepressant drugs there are several differences among them in efficacy, tolerability, and cost-effectiveness. In addition the optimal augmentation strategy is still not clear when dealing with treatment-resistant depression, a condition that affects 15% to 40% of depressed patients. Methods: We therefore reviewed the main characteristics of these drugs regarding their efficacy, tolerability, side effects and cost-effectiveness, by accessing all meta-analyses and systematic reviews published from 2004 to 2009. In addition, we reviewed the augmentation strategy of associated antidepressants with neurostimulation therapies (such as transcranial magnetic stimulation [TMS] and transcranial direct current stimulation [tDCS]). A search was undertaken in MEDLINE, Web of Science, Cochrane, and Scielo databases. We included: 21 meta-analyses of antidepressant trials, 15 neurostimulation clinical trials and 8 studies of pharmacoeconomics. We then performed a comprehensive review on these articles. Results and Conclusion: Although recent meta-analyses suggest sertraline and escitalopram might have increased efficacy/tolerability, other studies and large pragmatic trials have not found these to be superior to other antidepressant drugs. Also, we did not identify any superior drug in terms of cost-effectiveness due to the different designs observed among pharmacoecomics studies. Side effects such as sexual dysfunction, gastrointestinal problems and weight gain were common causes of discontinuation. Tolerability was an important issue for novel neurostimulation interventions, such as TMS and tDCS. These therapies might be interesting augmentation strategies, considering their benign profile of side effects, if proper safety parameters are adopted.
Page 1 /7021
Display every page Item

Copyright © 2008-2017 Open Access Library. All rights reserved.