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1.
An Acad Bras Cienc ; 93(suppl 1): e20201096, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34076206

RESUMO

BINGO (BAO from Integrated Neutral Gas Observations) is a unique radio telescope designed to map the intensity of neutral hydrogen distribution at cosmological distances, making the first detection of Baryon Acoustic Oscillations (BAO) in the frequency band 980 MHz - 1260 MHz, corresponding to a redshift range 0.127 < z < 0.449. BAO is one of the most powerful probes of cosmological parameters and BINGO was designed to detect the BAO signal to a level that makes it possible to put new constraints on the equation of state of dark energy. The telescope will be built in Paraíba, Brazil and consists of two \thicksim 40m mirrors, a feedhorn array of 50 horns, and no moving parts, working as a drift-scan instrument. It will cover a 15 ^{\circ} ∘ declination strip centered at \sim \delta ∼ δ =-15 ^{\circ} ∘ , mapping \sim ∼ 5400 square degrees in the sky. The BINGO consortium is led by University of São Paulo with co-leadership at National Institute for Space Research and Campina Grande Federal University (Brazil). Telescope subsystems have already been fabricated and tested, and the dish and structure fabrication are expected to start in late 2020, as well as the road and terrain preparation.

2.
Dev Neurosci ; 42(5-6): 230-236, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33706310

RESUMO

The tuberous sclerosis complex (TSC), focal cortical dysplasia IIB (FCD IIB), and hemimegalencephaly (HME) exhibit similar molecular features that are dependent on the hyperactivation of the mTOR pathway. They are all associated with refractory epilepsy and the need for surgical resection with varying outcomes. The phosphorylated protein S6 (pS6) is a downstream target of mTOR, whose increased expression might indicate mTOR hyperactivation, but which is also present when there is no alteration in the pathway (such as in FCD type I). We have performed immunohistochemical marking and quantification of pS6 in resected brain specimens of 26 patients clinically and histologically diagnosed with TSC, FCD IIB, or HME and compared this data to a control group of 25 patients, to measure the extent of pS6 positivity and its correlation with clinical aspects. Our results suggest that pS6 may serve as a reliable biomarker in epilepsy and that a greater percentage of pS6 marking can relate to more severe forms of mTOR-dependent brain anomalies.


Assuntos
Biomarcadores/metabolismo , Epilepsia Resistente a Medicamentos/metabolismo , Proteína S6 Ribossômica/metabolismo , Adolescente , Criança , Pré-Escolar , Epilepsia Resistente a Medicamentos/etiologia , Epilepsia Resistente a Medicamentos/cirurgia , Epilepsia/complicações , Epilepsia/metabolismo , Epilepsia/cirurgia , Feminino , Hemimegalencefalia/complicações , Hemimegalencefalia/metabolismo , Hemimegalencefalia/cirurgia , Humanos , Lactente , Masculino , Malformações do Desenvolvimento Cortical do Grupo I/complicações , Malformações do Desenvolvimento Cortical do Grupo I/metabolismo , Malformações do Desenvolvimento Cortical do Grupo I/cirurgia , Fosforilação , Esclerose Tuberosa/complicações , Esclerose Tuberosa/metabolismo , Esclerose Tuberosa/cirurgia
4.
Pediatr Neurol ; 150: 82-90, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37992429

RESUMO

BACKGROUND: Rasmussen encephalitis (RE) is characterized by pharmacoresistant epilepsy and progressive neurological deficits concurrent with unilateral hemispheric atrophy. Evidence of an inflammatory autoimmune process has been extensively described in the literature; however, the precise etiology of RE is still unknown. Despite data supporting a beneficial effect of early immunosuppressive and immunomodulatory interventions, surgical disconnection of the affected hemisphere is considered the treatment of choice for these patients. The aim of this study was to report a series of children and adolescents who underwent hemispheric surgery (HS) for the treatment of RE, analyzing their clinical, electrographic, and neuroimaging features pre-operatively, as well as their postoperative status, including seizure and functional outcomes. METHODS: All patients with RE who underwent HS in the Epilepsy Surgery Center (CIREP) of the University Hospital of Ribeirão Preto Medical School, between 1995 and 2020 were retrospectively reviewed. Preoperative and postoperative analyses included gender; age at epilepsy onset; seizure semiology; seizure frequency; interictal and ictal electroencephalographic (EEG) findings; age at surgery; duration of epilepsy; surgical complications; duration of follow-up; histopathological findings; and postoperative seizure, cognitive, and functional outcomes. RESULTS: Forty-four patients were evaluated. Mean age at seizure onset and epilepsy duration was 6 years and 2.5 years, respectively. Mean age at surgery was 9 years, with an average follow-up ranging from 3 months to 23 years. All patients presented with severe epilepsy and distinct neurological abnormalities on MRI. Before HS, different degrees of abnormal intellectual performance as well as hemiparesis were seen in 86% and 90%, respectively. Histopathology examination confirmed this diagnosis in 95% patients. At the last follow-up, 68% of patients were seizure free, and 70% were classified as Engel Class I or II. Postoperatively, the cognitive status remained unchanged in 64% of patients. Likewise, the gross motor function remained unchanged in 54% of patients and 74% had functional hand ability after HS. CONCLUSIONS: Considering the progressive damage course of RE, hemispheric surgery should be offered to pediatric patients. It has manageable risks and results in good seizure outcome, and the preoperative functional status of these children is often preserved (even when the left hemisphere is involved), thus improving their quality of life.


Assuntos
Encefalite , Epilepsia , Hemisferectomia , Adolescente , Criança , Humanos , Hemisferectomia/efeitos adversos , Hemisferectomia/métodos , Resultado do Tratamento , Estudos Retrospectivos , Qualidade de Vida , Convulsões/etiologia , Encefalite/diagnóstico por imagem , Encefalite/cirurgia , Encefalite/complicações , Eletroencefalografia/métodos
5.
J Pediatr (Rio J) ; 99(3): 228-234, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36493803

RESUMO

OBJECTIVE: Describe the epidemiological profile and social-economic burden that hydrocephalus patients represent to the national public health system, using data available at the online database of the Brazilian Health Ministry (DataSUS). METHODS: This is a populational study based on descriptive statistics of all clinical and surgical appointments included in the DataSUS database. Data included herein were collected between 2015 and 2021 and subdivided into three main groups, related to hydrocephalus incidence and mortality, hospitalizations, and financial costs. RESULTS: In the study period, 3993 new cases of congenital hydrocephalus were diagnosed, with 6051 deaths overall. The mortality rate in the country was 1.5/100000 live births and the prevalence was 0.374/100000 inhabitants. The number of hospitalizations resulting from treatment procedures and complications of hydrocephalus was 137,880 and there was a reduction of up to 27.2% during the SARS-CoV-2 pandemics concerning previous years. Total costs for hydrocephalus management in the country amounted to 140,610,585.51 dollars. CONCLUSIONS: Hydrocephalus has a significant impact on public health budgets and pediatric mortality rates; however, it is probably underestimated, due to the paucity of demographic data and epidemiological studies in Latin America and, specifically, in Brazil. The dataSUS also has several limitations in accessing certain data related to hydrocephalus, making it difficult to have a more assertive understanding of the disease in Brazil. The results of this study provide important guidance for future research projects in clinical and experimental hydrocephalus and also the creation of public policies for better governance and care of hydrocephalus patients.


Assuntos
COVID-19 , Hidrocefalia , Humanos , Criança , Brasil/epidemiologia , SARS-CoV-2 , Incidência , Hidrocefalia/epidemiologia
6.
Materials (Basel) ; 14(2)2021 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-33419103

RESUMO

17-4PH stainless steel specimens were fabricated by fused deposition of metals (FDMet) technology, which combines 17-4PH particles with an organic binder. FDMet promises a low-cost additive manufacturing process. The present research aims to clarify the influence of layer directions in the 3D printing process on the mechanical and shrinkage properties of as-sintered and as-aged specimens. All specimens (the as-sintered and as-aged specimens printed in three layer directions) exhibited high relative density (97.5-98%). The highest ultimate strengths (880 and 1140 MPa in the as-sintered and as-aged specimens, respectively) were obtained when the layer direction was perpendicular to the tensile direction. Conversely, the specimens printed with their layer direction parallel to the tensile direction presented a low ultimate strength and low strain at breakage. The fact that the specimens with their layer direction parallel to the tensile direction presented a low ultimate strength and low strain at breakage is a usual behavior of parts obtained by means of FDM. The SEM images revealed oriented binder domains in the printed parts and oriented voids in the sintered parts. It was assumed that large binder domains in the filament were oriented perpendicular to the layer directions during the fused deposition modeling printing, and remained as oriented voids after sintering. Stress concentration in the oriented void defects was likely responsible for the poor tensile properties of these specimens.

7.
Cureus ; 13(2): e13587, 2021 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-33815990

RESUMO

Objective With the aging of the global population, an increase in the proportion of elderly patients presenting with traumatic brain injury (TBI) is expected. This population presents several distinctive characteristics that impact management and outcome of TBI, such as comorbidities, frailty, and preinjury use of medications - specially antiplatelets and anticoagulants. The purpose of this study was to assess the general characteristics and prognostic factors of elderly patients with TBI that were surgically managed at a single institution. Methods The authors performed a retrospective review of all elderly patients (age ≥ 65 years) with a history of TBI that underwent cranial neurosurgical procedures at their institution, between 2015 and 2019. Clinical characteristics, laboratory tests, and radiological scans, as well as surgeries, performed, outcome, and prognostic factors were analyzed, comprising 133 consecutive cases overall. Results The mean age of patients was 76.6 ± 7.3 years, ranging from 65 years to 97 years. There was a predominance of males (71.4%) and the most frequent mechanism of injury was fall (80.4%). Mild TBI comprised 57.1% of the cases, followed by severe TBI in 25.6%. Frequent signs and symptoms were impaired consciousness (69.9%), focal motor deficits (32.3%), and gait disturbances (12.8%). The majority had reported comorbidities upon admission (79.7%), with cardiac disease (79.2%) and diabetes (24.5%) as the most frequent. Preinjury anticoagulation was reported in 18.8% and use of antiplatelet drugs in 17.3%. The most common finding in the head CT was chronic subdural hematoma (48.1%), followed by acute subdural hematoma (37.6%). Coagulation was found to be altered in 12.8% of the patients. The most common neurosurgical procedure performed was trephination for hematoma evacuation (56.3%), followed by craniotomy (21.2%). Blood product transfusion was needed in 61.7% of the patients. Overall mortality was 42.1%, with the majority in the first month after admission (83.9%). Unfavorable outcome (Glasgow Outcome Scale <5) at discharge was identified in 73% of the patients. Identified prognostic factors were TBI severity, absent pupillary reactivity, acute intracranial bleeding on head CT, basal cisterns obliteration, altered coagulation status, and need for blood transfusion. Conclusions TBI severity, pupillary reactivity, coagulation status, need for blood products transfusion and acute bleeding, as well as basal cisterns obliteration found in head CT, are factors that influenced the outcome in this series of elderly patients with TBI that need surgical management. It is paramount to observe the particularities of this population in this context, to optimize outcomes, avoid complications and ultimately generate awareness focused on prevention.

8.
Materials (Basel) ; 13(11)2020 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-32486111

RESUMO

Metal specimens were fabricated via the fused deposition of metals (FDMet) technique with a filament composed of the 316L stainless steel particles and an organic binder. This process was adopted due to its potential as a low-cost additive manufacturing process. The objective of this study is to investigate the influence of the processing conditions-layer directions and layer thicknesses-on the mechanical and shrinkage properties of the metal components. The specimens were printed in three different layer directions. The highest ultimate strength of 453 MPa and strain at break of 48% were obtained in the specimen printed with the layer direction perpendicular to the tensile direction. On the other hand, the specimen printed in the layer direction parallel to the tensile direction exhibited poor mechanical properties. The reason for the anisotropy of the properties was investigated through systematic SEM observations. The observations revealed the presence of segregated binder domains in the filaments. It was deduced that the binder domain was oriented in the direction perpendicular to that of the layer and remained as oriented voids even after sintering. The voids oriented perpendicular to the tensile direction act as defects that could cause stress concentration, thus resulting in poor mechanical properties.

9.
Epilepsia Open ; 5(1): 97-106, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32140648

RESUMO

OBJECTIVES: Recently, defects in the protein kinase mTOR (mammalian target of rapamycin) and its associated pathway have been correlated with hemimegalencephaly (HME). mTOR acts as a central regulator of important physiological cellular functions such as growth and proliferation, metabolism, autophagy, death, and survival. This study was aimed at identifying specific variants in mTOR signaling pathway genes in patients diagnosed with HME. METHODS: Using amplicon and whole exome sequencing (WES) of resected brain and paired blood samples from five HME patients, we were able to identify pathogenic mosaic variants in the mTOR pathway genes MTOR, PIK3CA, and DEPDC5. RESULTS: These results strengthen the hypothesis that somatic variants in PI3K-Akt-mTOR pathway genes contribute to HME. We also describe one patient presenting with a pathogenic variant on DEPDC5 gene, which reinforces the role of DEPDC5 on cortical structural changes due to mTORC1 hyperactivation. These findings also provide insights into when in brain development these variants occurred. An early developmental variant is expected to affect a larger number of cells and to result in a larger malformation, whereas the same variant occurring later in development would cause a minor malformation. SIGNIFICANCE: In the future, numerous somatic variants in known or new genes will undoubtedly be revealed in resected brain samples, making it possible to draw correlations between genotypes and phenotypes and allow for a genetic clinical diagnosis that may help to predict a given patient's outcome.

10.
Cureus ; 10(6): e2836, 2018 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-30131929

RESUMO

Pott's puffy tumor is a rare and severe complication of frontal sinusitis, characterized by the progressive swelling of the frontal soft tissues secondary to a subperiosteal abscess. Radiological imaging with ultrasound, computed tomography (CT), and magnetic resonance imaging (MRI) are important diagnostic tools in establishing diagnosis and treatment planning. Early surgery along with intravenous antibiotics are required in order to achieve a good recovery. The authors report a case of Pott's puffy tumor in an obese 14-year-old male, with a previous history of asthma and a chronic use of steroids, treated with neurosurgical debridement followed by a combined course of intravenous (IV) and oral antibiotics, who had a favorable outcome upon long-term follow-up. In addition, a brief review of the current medical literature was performed for a discussion on the diagnostic and therapeutic features of this pathology.

11.
J. pediatr. (Rio J.) ; 99(3): 228-234, May-June 2023. graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1440466

RESUMO

Abstract Objective Describe the epidemiological profile and social-economic burden that hydrocephalus patients represent to the national public health system, using data available at the online database of the Brazilian Health Ministry (DataSUS). Methods This is a populational study based on descriptive statistics of all clinical and surgical appointments included in the DataSUS database. Data included herein were collected between 2015 and 2021 and subdivided into three main groups, related to hydrocephalus incidence and mortality, hospitalizations, and financial costs. Results In the study period, 3993 new cases of congenital hydrocephalus were diagnosed, with 6051 deaths overall. The mortality rate in the country was 1.5/100000 live births and the prevalence was 0.374/100000 inhabitants. The number of hospitalizations resulting from treatment procedures and complications of hydrocephalus was 137,880 and there was a reduction of up to 27.2% during the SARS-CoV-2 pandemics concerning previous years. Total costs for hydrocephalus management in the country amounted to 140,610,585.51 dollars. Conclusions Hydrocephalus has a significant impact on public health budgets and pediatric mortality rates; however, it is probably underestimated, due to the paucity of demographic data and epidemiological studies in Latin America and, specifically, in Brazil. The dataSUS also has several limitations in accessing certain data related to hydrocephalus, making it difficult to have a more assertive understanding of the disease in Brazil. The results of this study provide important guidance for future research projects in clinical and experimental hydrocephalus and also the creation of public policies for better governance and care of hydrocephalus patients.

12.
J Pediatr Neurosci ; 7(1): 43-6, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22837778

RESUMO

Cavernous hemangioma (CH) is a sporadic vascular malformation occurring either as an autosomal dominant condition or as a well-known complication of radiation exposure. Medulloblastoma is a primitive neuroectodermal tumor common in children and currently treated with surgical resection, chemotherapy, and radiotherapy. Neurofibromatosis is the most common single-gene disorder of the central nervous system. Posterior fossa malignant tumors in the context of neurofibromatosis type I (NF1) are very infrequent. This is the first documented case of an unusual metachronous occurrence of non-radiation-induced CH and medulloblastoma in a child with NF1 phenotype. We report the case of a 13-month-old boy with café-au-lait skin lesions associated with NF1-like phenotype who underwent surgical resection of a single CH in the temporal lobe due to recurrent seizures. Four years later he presented with signs of raised intracranial pressure associated with a posterior fossa tumor and hydrocephalus, thus requiring gross total resection of the lesion. Histological analysis revealed a medulloblastoma. After being treated with radiotherapy and chemotherapy, he achieved total remission. Six years later a massive recurrence of the tumor was observed and the child eventually died. The interest in this case lies in the rarity of NF1-like phenotype associated with a non-radiation-induced brain CH and medulloblastoma in a child.

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