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Dive into the research topics where Gabriel R. de Freitas is active.

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Featured researches published by Gabriel R. de Freitas.


Lancet Neurology | 2009

Treatment and outcomes of acute basilar artery occlusion in the Basilar Artery International Cooperation Study (BASICS): a prospective registry study.

Wouter J. Schonewille; Christine A.C. Wijman; Patrik Michel; Christina Rueckert; Christian Weimar; Heinrich P. Mattle; Stefan T. Engelter; David Tanne; Keith W. Muir; Carlos A. Molina; Vincent Thijs; Heinrich J. Audebert; Thomas Pfefferkorn; Kristina Szabo; Perttu J. Lindsberg; Gabriel R. de Freitas; L. Jaap Kappelle; Ale Algra

BACKGROUND Treatment strategies for acute basilar artery occlusion (BAO) are based on case series and data that have been extrapolated from stroke intervention trials in other cerebrovascular territories, and information on the efficacy of different treatments in unselected patients with BAO is scarce. We therefore assessed outcomes and differences in treatment response after BAO. METHODS The Basilar Artery International Cooperation Study (BASICS) is a prospective, observational registry of consecutive patients who presented with an acute symptomatic and radiologically confirmed BAO between November 1, 2002, and October 1, 2007. Stroke severity at time of treatment was dichotomised as severe (coma, locked-in state, or tetraplegia) or mild to moderate (any deficit that was less than severe). Outcome was assessed at 1 month. Poor outcome was defined as a modified Rankin scale score of 4 or 5, or death. Patients were divided into three groups according to the treatment they received: antithrombotic treatment only (AT), which comprised antiplatelet drugs or systemic anticoagulation; primary intravenous thrombolysis (IVT), including subsequent intra-arterial thrombolysis; or intra-arterial therapy (IAT), which comprised thrombolysis, mechanical thrombectomy, stenting, or a combination of these approaches. Risk ratios (RR) for treatment effects were adjusted for age, the severity of neurological deficits at the time of treatment, time to treatment, prodromal minor stroke, location of the occlusion, and diabetes. FINDINGS 619 patients were entered in the registry. 27 patients were excluded from the analyses because they did not receive AT, IVT, or IAT, and all had a poor outcome. Of the 592 patients who were analysed, 183 were treated with only AT, 121 with IVT, and 288 with IAT. Overall, 402 (68%) of the analysed patients had a poor outcome. No statistically significant superiority was found for any treatment strategy. Compared with outcome after AT, patients with a mild-to-moderate deficit (n=245) had about the same risk of poor outcome after IVT (adjusted RR 0.94, 95% CI 0.60-1.45) or after IAT (adjusted RR 1.29, 0.97-1.72) but had a worse outcome after IAT compared with IVT (adjusted RR 1.49, 1.00-2.23). Compared with AT, patients with a severe deficit (n=347) had a lower risk of poor outcome after IVT (adjusted RR 0.88, 0.76-1.01) or IAT (adjusted RR 0.94, 0.86-1.02), whereas outcomes were similar after treatment with IAT or IVT (adjusted RR 1.06, 0.91-1.22). INTERPRETATION Most patients in the BASICS registry received IAT. Our results do not support unequivocal superiority of IAT over IVT, and the efficacy of IAT versus IVT in patients with an acute BAO needs to be assessed in a randomised controlled trial. FUNDING Department of Neurology, University Medical Center Utrecht.


Experimental Neurology | 2010

Migration and homing of bone-marrow mononuclear cells in chronic ischemic stroke after intra-arterial injection

Lea Mirian Barbosa da Fonseca; Bianca Gutfilen; Paulo Castro; Valeria Battistella; Regina Coeli dos Santos Goldenberg; Tais Hanae Kasai-Brunswick; Claudia L.R. Chagas; Eduardo Wajnberg; Angelo Maiolino; Sérgio Salles Xavier; Charles André; Rosalia Mendez-Otero; Gabriel R. de Freitas

Cell-based treatments have been considered a promising therapy for neurological diseases. However, currently there are no clinically available methods to monitor whether the transplanted cells reach and remain in the brain. In this study we investigated the feasibility of detecting the distribution and homing of autologous bone-marrow mononuclear cells (BMMCs) labeled with Technetium-99 m ((99m)Tc) in a cell-based therapy clinical study for chronic ischemic stroke. Six male patients (ages 24-65 years) with ischemic cerebral infarcts within the middle cerebral artery (MCA) between 59 and 82 days were included. Cell dose ranged from 1.25x10(8) to 5x10(8). Approximately 2x10(7) cells were labeled with (99m)Tc and intra-arterially delivered together with the unlabeled cells via a catheter navigated to the MCA. None of the patients showed any complications on the 120-day follow-up. Whole body scintigraphies indicated cell homing in the brain of all patients at 2 h, while the remaining uptake was mainly distributed to liver, lungs, spleen, kidneys and bladder. Moreover, quantification of uptake in Single-Photon Emission Computed Tomography (SPECT) at 2 h showed preferential accumulation of radioactivity in the hemisphere affected by the ischemic infarct in all patients. However, at 24 h homing could only distinguished in the brains of 2 patients, while in all patients uptake was still seen in the other organs. Taken together, these results indicate that labeling of BMMCs with (99m)Tc is a safe and feasible technique that allows monitoring the migration and engraftment of intra-arterially transplanted cells for at least 24 h.


Regenerative Medicine | 2011

Safety of autologous bone marrow mononuclear cell transplantation in patients with nonacute ischemic stroke

Valeria Battistella; Gabriel R. de Freitas; Lea Mirian Barbosa da Fonseca; Daniel Mercante; Bianca Gutfilen; R.C.S. Goldenberg; Juliana Dias; Tais Hanae Kasai-Brunswick; Eduardo Wajnberg; Paulo Henrique Rosado-de-Castro; Soniza Vieira Alves-Leon; Rosalia Mendez-Otero; Charles André

AIMS To assess the safety and feasibility of intra-arterial transplantation of autologous bone marrow mononuclear cells in patients with middle cerebral artery ischemic stroke within 90 days of symptom onset. PATIENTS & METHODS Six patients were included in the study, and they received 1-5 × 10(8) bone marrow mononuclear cell and were evaluated using blood tests, neurological and imaging examination before treatment, and 1, 3, 7, 30, 60, 90, 120 and 180 days after transplantation. Scintigraphies were carried out 2 and 24 h after the procedure to analyze the biodistribution of labeled cells. Electroencephalogram was conducted within 7 days after transplantation. RESULTS No patients exhibited any complication or adverse events during the procedure. There was no worsening in the neurological scales until the end of the follow-up. CONCLUSION Intra-arterial bone marrow mononuclear cell transplantation is feasible and safe in patients with nonacute ischemic strokes of the middle cerebral artery. Further studies are required to evaluate the efficacy of this therapy.


Clinical Nuclear Medicine | 2007

Assessment of intra-arterial injected autologous bone marrow mononuclear cell distribution by radioactive labeling in acute ischemic stroke.

Patrícia Lavatori Corrêa; Cláudio Tinoco Mesquita; Renata M. Felix; Jader Cunha de Azevedo; Gustavo Borges Barbirato; Carlos Henrique Falcão; Constantino Gonzalez; Maria Lúcia Furtado de Mendonça; Aquiles Manfrim; Gabriel R. de Freitas; Cristina C. Oliveira; Daniel Silva; Dione Ávila; Radovan Borojevic; Suzana Alves; Amarino C. Oliveira; Hans F. Dohmann

Objective: To evaluate the feasibility of monitoring the autologous mononuclear bone marrow (ABMMN) cells implanted into the brain after acute ischemic stroke by the technique of labeling with Tc-99m-HMPAO. Case Report: A 37-year-old man presented with aphasia, right-side hypoesthesia, and right homonymous hemianopsia after an acute ischemic stroke of the left middle cerebral artery. He was included in an autologous bone marrow mononuclear cell-based therapy research protocol about the safety of intra-arterial autologous bone marrow mononuclear cell transplantation for acute ischemic stroke. Nine days after the stroke he received 3.0 × 107 ABMMN cells delivered into the left cerebral middle artery via a balloon catheter. Approximately 1% of these cells were labeled with 150 MBq (4 mCi) Tc-99m by incubation with hexamethylpropylene amine oxime (HMPAO). Results: Brain perfusion images with Tc-99m ECD demonstrated hypoperfusion in the left temporal and parietal regions. The perfusion brain images were compared with tomographic views of the brain obtained 8 hours after ABMMN-labeled cell delivery, revealing intense accumulation of the ABMMN-labeled cells in the ipsilateral hemisphere. A whole-body scan was done and showed left brain, liver, and spleen uptake. Conclusions: Our results showed that Tc-99m HMPAO can be used to label ABMMN cells for in vivo cell visualization, and that brain SPECT imaging with labeled ABMMN cells is a feasible noninvasive method for studying the fate of transplanted cells in vivo. Additionally, our findings demonstrate the localization of these intra-arterially injected cells.


Regenerative Medicine | 2013

Biodistribution of bone marrow mononuclear cells after intra-arterial or intravenous transplantation in subacute stroke patients

Paulo Henrique Rosado-de-Castro; Felipe Rocha Schmidt; Valeria Battistella; Sergio Augusto Lopes de Souza; Bianca Gutfilen; Regina Coeli dos Santos Goldenberg; Tais Hanae Kasai-Brunswick; Leandro Vairo; Rafaella Monteiro Silva; Eduardo Wajnberg; Pedro Emmanuel do Brasil; Emerson Leandro Gasparetto; Angelo Maiolino; Soniza Vieira Alves-Leon; Charles André; Rosalia Mendez-Otero; Gabriel R. de Freitas; Lea Mirian Barbosa da Fonseca

AIMS To assess the biodistribution of bone marrow mononuclear cells (BMMNC) delivered by different routes in patients with subacute middle cerebral artery ischemic stroke. PATIENTS & METHODS This was a nonrandomized, open-label Phase I clinical trial. After bone marrow harvesting, BMMNCs were labeled with technetium-99m and intra-arterially or intravenously delivered together with the unlabeled cells. Scintigraphies were carried out at 2 and 24 h after cell transplantation. Clinical follow-up was continued for 6 months. RESULTS Twelve patients were included, between 19 and 89 days after stroke, and received 1-5 × 10(8) BMMNCs. The intra-arterial group had greater radioactive counts in the liver and spleen and lower counts in the lungs at 2 and 24 h, while in the brain they were low and similar for both routes. CONCLUSION BMMNC labeling with technetium-99m allowed imaging for up to 24 h after intra-arterial or intravenous injection in stroke patients.


Regenerative Medicine | 2007

Potential roles of bone marrow stem cells in stroke therapy

Rosalia Mendez-Otero; Gabriel R. de Freitas; Charles André; Maria Lúcia Furtado de Mendonça; Maurício André Gheller Friedrich; Jamary Oliveira-Filho

There is a need for improved therapies, in terms of utility and effectiveness, for stroke patients; however, over the years, numerous clinical trials of potential drugs have failed to demonstrate positive results. The emerging field of stem cell research has raised several hopes of a therapy for neurological diseases, including stroke. This review discusses the recent clinical trials and pilot studies using stem cells in stroke patients and highlights key issues that must be addressed to improve the chances of successfully developing a new strategy for stroke patients using adult stem cells.


Clinical Chemistry and Laboratory Medicine | 2006

Role of serum S100B as a predictive marker of fatal outcome following isolated severe head injury or multitrauma in males.

Adriana Brondani da Rocha; Rogério Fett Schneider; Gabriel R. de Freitas; Charles André; Ivana Grivicich; Caroline Zanoni; Aline Fossá; Junia Thirzah Gehrke; Geraldo Pereira Jotz; Mauro Kaufmann; Daniel Simon; Andrea Regner

Abstract Background: Severe traumatic brain injury (TBI) is associated with a 30%–70% mortality rate. S100B has been proposed as a biomarker for indicating outcome after TBI. Nevertheless, controversy has arisen concerning the predictive value of S100B for severe TBI in the context of multitrauma. Therefore, our aim was to determine whether S100B serum levels correlate with primary outcome following isolated severe TBI or multitrauma in males. Methods: Twenty-three consecutive male patients (age 18–65years), victims of severe TBI [Glasgow Coma Scale (GCS) 3–8] (10 isolated TBI and 13 multitrauma with TBI) and a control group consisting of eight healthy volunteers were enrolled in this prospective study. Clinical outcome variables of severe TBI comprised: survival, time to intensive care unit (ICU) discharge, and neurological assessment [Glasgow Outcome Scale (GOS) at ICU discharge]. Venous blood samples were taken at admission in the ICU (study entry), 24h later, and 7days later. Serum S100B concentration was measured by an immunoluminometric assay. Results: At study entry (mean time 10.9h after injury), mean S100B concentrations were significantly increased in the patient with TBI (1.448μg/L) compared with the control group (0.037μg/L) and patients with fatal outcome had higher mean S100B (2.10μg/L) concentrations when compared with survivors (0.85μg/L). In fact, there was a significant correlation between higher initial S100B concentrations and fatal outcome (Spearmans =0.485, p=0.019). However, there was no correlation between higher S100B concentrations and the presence of multitrauma. The specificity of S100B in predicting mortality according to the cut-off of 0.79μg/L was 73% at study entry. Conclusions: Increased serum S100B levels constitute a valid predictor of unfavourable outcome in severe TBI, regardless of the presence of associated multitrauma. Clin Chem Lab Med 2006;44:1234–42.


Arquivos Brasileiros De Cardiologia | 2006

Segurança do transplante autólogo, intra-arterial, de células mononucleares da medula óssea na fase aguda do acidente vascular cerebral isquêmico

Maria Lúcia Furtado de Mendonça; Gabriel R. de Freitas; Suzana A. Silva; Aquiles Manfrim; Carlos Henrique Falcão; Constantino Gonzáles; Charles André; Hans Fernando Rocha Dohmann; Radovan Borojevic; Rosália Mendez Otero

Stroke is the third cause of death and the leading cause of disability in adult subjects. Although stroke mortality has been declining in some countries, stroke morbidity has been increasing due to the aging of population and patients improved survival.1 Treatment with recombinant tissue plasminogen activator (rtPA) is successful provided it is administered within 3 hours of symptoms onset,2 but its use is limited to about 5% of the patients with acute ischemic stroke. Furthermore, no neuroprotective agent has yet been proven effective in human clinical trials. The development of other therapeutic strategies is, therefore, warranted. The use of stem cells in animal models has led to functional improvement following stroke.3 Recent publications have shown that bone marrow mononuclear cells (BM-MNC) therapy through intracoronary injection is a safe procedure in patients with acute or chronic ischemic heart disease.4,5 Based on these preliminary data, there has been growing interest in the study of BM-MNC transplantation for acute ischemic stroke. We report the first case of intra-arterial autologous BM-MNC transplantation for acute ischemic stroke.


Stem Cells and Development | 2013

The Rise of Cell Therapy Trials for Stroke: Review of Published and Registered Studies

Paulo Henrique Rosado-de-Castro; Pedro M. Pimentel-Coelho; Lea Mirian Barbosa da Fonseca; Gabriel R. de Freitas; Rosalia Mendez-Otero

Stroke is the second leading cause of death and the third leading cause of disability worldwide. Approximately 16 million first-ever strokes occur each year, leading to nearly 6 million deaths. Nevertheless, currently, very few therapeutic options are available. Cell therapies have been applied successfully in different hematological diseases, and are currently being investigated for treating ischemic heart disease, with promising results. Recent preclinical studies have indicated that cell therapies may provide structural and functional benefits after stroke. However, the effects of these treatments are not yet fully understood and are the subject of continuing investigation. Meanwhile, different clinical trials for stroke, the majority of them small, nonrandomized, and uncontrolled, have been reported, and their results indicate that cell therapy seems safe and feasible in these conditions. In the last 2 years, the number of published and registered trials has dramatically increased. Here, we review the main findings available in the field, with emphasis on the clinical results. Moreover, we address some of the questions that have been raised to date, to improve future studies.


Stem Cell Research | 2012

Intravenous and intra-arterial administration of bone marrow mononuclear cells after focal cerebral ischemia: Is there a difference in biodistribution and efficacy?

Andréia Vasconcelos-dos-Santos; Paulo Henrique Rosado-de-Castro; Sergio Augusto Lopes de Souza; Juliana da Costa Silva; Alane Bernardo Ramos; Gabriel R. de Freitas; Lea Mirian Barbosa da Fonseca; Bianca Gutfilen; Rosalia Mendez-Otero

Intravascular delivery of cells has been increasingly used in stroke models and clinical trials. We compared the biodistribution and therapeutic effects of bone marrow mononuclear cells (BMMCs) delivered by intra-arterial (IA) or intravenous (IV) injection after cortical ischemia. For the biodistribution analyses, BMMCs were labeled with (99m)Technetium ((99m)Tc). At 2 h, gamma-well counting of the brain and of the other organs evaluated did not show differences between the non-ischemic and ischemic groups or between injection routes, and the organs with the highest uptake were the liver and lungs, with low uptake in the brain. At 24 h, the liver maintained the highest activity, and a marked decrease was seen in pulmonary uptake in all groups. At this time point, although the activity in the brain remained low, the lesioned hemisphere showed greater homing than the contralateral hemisphere, for both the IV and IA ischemic groups. Histological analysis by CellTrace labeling indicated similar homing between both routes in the peri-infarct region 24 h after transplantation and functional recovery was observed in both groups up to 11 weeks after the lesion. In conclusion, transplantation of BMMCs by IA or IV routes may lead to similar brain homing and therapeutic efficacy after experimental stroke.

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Charles André

Federal University of Rio de Janeiro

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Rosalia Mendez-Otero

Federal University of Rio de Janeiro

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Juliana da Silva

Universidade Luterana do Brasil

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Neogélia Almeida

Federal University of Bahia

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Paulo Henrique Rosado-de-Castro

Federal University of Rio de Janeiro

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Lea Mirian Barbosa da Fonseca

Federal University of Rio de Janeiro

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Bianca Gutfilen

Federal University of Rio de Janeiro

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Eduardo Wajnberg

Federal University of Rio de Janeiro

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