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This work presents the study of a reproducible acoustic emission method based on the launching of a metallic sphere and low-cost piezoelectric diaphragm. For this purpose, tests were first conducted on a carbon fiber-reinforced polymer structure, and then on an aluminum structure for comparative analysis. The pencil-lead break (PLB) tests were also conducted for comparisons with the proposed method. Different launching heights and elastic deformations of the structures were investigated. The results show higher repeatability for the sphere impact method, as the PLB is more affected by human inaccuracy, and it was also effective in damage detection.
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Introduction: The Neurological Assessment for Neuro-Oncology (NANO) scale was elaborated to assess neurologic function in integration with radiological criteria to evaluate neuro-oncological patients in clinical setting and enable the standardization of neurological assessment in clinical trials. The objective of this study is the translation to Brazilian Portuguese and transcultural adaptation of NANO scale in patients with the diagnosis of glioblastoma, brain metastasis and low-grade glioma. Methods: Patients with diagnosis of glioblastoma, brain metastasis, and low-grade glioma were prospectively evaluated between July 2019 and July 2021. The process of translating and cross-culturally adapting the NANO scale included: translation from English to Portuguese, synthesis and initial revision by an expert committee, back-translation from Portuguese to English, a second revision by the expert committee, and the application of the NANO scale. Regarding the reliability of the NANO scale, Cronbach's alpha was employed to measure the internal consistency of all scale items and assess the impact of item deletion. Additionally, Spearman's correlation test was used to evaluate the convergent validity between the NANO scale and Karnofsky Performance Scale (KPS). Results: One hundred and seventy-four patients were evaluated. A statistically significant inverse relation (p < 0.001) between KPS and NANO scale was founded. The Cronbach's alpha values founded for NANO scale were 0.803 for glioblastoma, 0.643 for brain metastasis, and 0.482 for low grade glioma. Discussion: The NANO scale Brazilian Portuguese version proves to be reproducible and valid to evaluate neuro-oncological patients with glioblastoma and brain metastasis, presenting a strong correlation with KPS scale. Further studies are warranted to assess the validity and reliability of the scale in patients diagnosed with low-grade glioma.
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The drug-resistant temporal lobe epilepsy (TLE) has recently been associated with single nucleotide variants (SNVs) in microRNA(miR)-146a (MIR-146A) (rs2910164) and Sodium Voltage-Gated Channel Alpha Subunit 1 (SCN1A) (rs2298771 and rs3812718) genes. Moreover, no studies have shown an association between these SNVs and susceptibility to drug-resistant and drug-responsive TLE in Brazil. Thus, deoxyribonucleic acid (DNA) samples from 120 patients with TLE (55 drug-responsive and 65 drug-resistant) were evaluated by real-time polymerase chain reaction (RT-PCR). A total of 1171 healthy blood donor individuals from the Online Archive of Brazilian Mutations (ABraOM, from Portuguese Arquivo Brasileiro On-line de Mutações), a repository containing genomic variants of the Brazilian population, were added as a control population for the studied SNVs. MIR-146A and SCN1A relative expression was performed by quantitative RT-PCR (qRT-PCR). The statistical analysis protocol was performed using an alpha error of 0.05. TLE patient samples and ABraOM control samples were in Hardy-Weinberg equilibrium for all studied SNVs. For rs2910164, the frequencies of the homozygous genotype (CC) (15.00% vs. 9.65%) and C allele (37.80% vs. 29.97%) were superior in patients with TLE compared to controls with a higher risk for TLE disease [odds ratio (OR) = 1.89 (95% confidence interval (95%CI) = 1.06-3.37); OR = 1.38 (95%CI = 1.04-1.82), respectively]. Drug-responsive patients also presented higher frequencies of the CC genotype [21.81% vs. 9.65%; OR = 2.58 (95%CI = 1.25-5.30)] and C allele [39.09% vs. 29.97%; OR = 1.50 (95%CI = 1.01-2.22)] compared to controls. For rs2298771, the frequency of the heterozygous genotype (AG) (51.67% vs. 40.40%) was superior in patients with TLE compared to controls with a higher risk for TLE disease [OR = 2.42 (95%CI = 1.08-5.41)]. Drug-resistant patients presented a higher AG frequency [56.92% vs. 40.40%; OR = 3.36 (95%CI = 1.04-17.30)] compared to the control group. For rs3812718, the prevalence of genotypes and alleles were similar in both studied groups. The MIR-146A relative expression level was lower in drug-resistant compared to drug-responsive patients for GC (1.6 vs. 0.1, p-value = 0.049) and CC (1.8 vs. 0.6, p-value = 0.039). Also, the SCN1A relative expression levels in samples from TLE patients were significantly higher in AG [2.09 vs. 1.10, p-value = 0.038] and GG (3.19 vs. 1.10, p-value < 0.001) compared to the AA genotype. In conclusion, the rs2910164-CC and rs2298771-AG genotypes are exerting significant risk influence, respectively, on responsive disease and resistant disease, probably due to an upregulated nuclear factor kappa B (NF-kB) and SCN1A loss of function.
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Epilepsia del Lóbulo Temporal , MicroARNs , Canal de Sodio Activado por Voltaje NAV1.1 , Polimorfismo de Nucleótido Simple , Humanos , Canal de Sodio Activado por Voltaje NAV1.1/genética , MicroARNs/genética , Epilepsia del Lóbulo Temporal/genética , Epilepsia del Lóbulo Temporal/tratamiento farmacológico , Femenino , Masculino , Brasil , Adulto , Predisposición Genética a la Enfermedad , Epilepsia Refractaria/genética , Epilepsia Refractaria/tratamiento farmacológico , Persona de Mediana Edad , Adulto Joven , Genotipo , Estudios de Cohortes , Alelos , Frecuencia de los Genes , Adolescente , Estudios de Casos y ControlesRESUMEN
OBJECTIVE: The objective of this study was to analyze the trends in publications on intrathecal baclofen (ITB) therapy. METHODS: We searched Elsevier's Scopus database in February 2022 to find articles focused on ITB therapy. Data extracted included citation count, publication year, author's country and income category, journal and its 5-year impact factor, research type, disease requiring ITB, and target population. RESULTS: The analysis covered 615 articles from 1985 to 2022. The average citation count per article was 27.47 (95% confidence interval 23.75-31.18) and the mean impact factor was 4.54 (95% confidence interval 3.84-5.24). The majority (76.42%) were primary research, with 8.1% being interventional and 91.9% observational. Even so, one half of the top ten most cited were interventional. Secondary research and case reports made up 12.68% and 10.73% respectively, with narrative reviews making up most of the secondary research (79.48%). Only 1 study conducted a meta-analysis. The United States was the most prolific country. High-income countries published 96.42% of articles. CONCLUSIONS: The rising number of ITB articles and citations indicates growing interest and expanding knowledge in this field. However, there's a notable scarcity of research from low- and middle-income countries, particularly those with high prevalence of ITB-treatable diseases. The need for more evidence to overcome potential barriers to ITB implementation is emphasized. Despite an increasing number of publications, a large proportion presented low levels of evidence, such as case reports and narrative reviews, highlighting the need for more rigorous research methods to solidify the evidence base for ITB therapy.
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Baclofeno , Bibliometría , Humanos , Estados Unidos , Proyectos de Investigación , Bases de Datos FactualesRESUMEN
Introdução: A incapacidade funcional e o desempenho físico são definidos pela dificuldade ou necessidade de ajuda para o indivíduo executar tarefas diárias, podendo repercutir na capacidade adaptativa das atividades diárias, tanto nas suas capacidades físicas quanto mentais. O processo de envelhecimento acarreta incapacidade funcional, comprometendo a qualidade de vida. Objetivo geral: Construir um aplicativo em saúde com foco na saúde do idoso com incapacidade na lombar. Métodos: Trata-se de um estudo do tipo construção de um aplicativo, desenvolvido durante o período de agosto de 2021 a maio de 2022 em Fortaleza-CE, na página https://fabricadeaplicativos.com.br e será disponibilizado com um instrumento composto pelo índice de Oswestry 2.0 de Incapacidade. Resultados: Telas explicativas para download e acesso ao aplicativo desenvolvido para facilitar o alcance de informações relevantes aos idosos que sofrem limitações no seu dia a dia, provenientes do processo de envelhecimento. Conclusão: Tendo visto que existem poucos estudos e aplicativos sobre esse assunto, se faz necessário a criação de um aplicativo voltado ao tema.(AU)
Introduction: Functional disability and physical performance are defined by the difficulty or need for help for the individual to perform daily tasks. It can have repercussions on the adaptive capacity of daily activities, both in their physical and mental capacities. The aging process causes functional disability, thus compromising quality of life. General objective: To build a health application focused on the health of the elderly with disabilities in the lumbar. Methods: This is a study of the type of construction of an application, developed during the period from August 2021 to May 2022 in Fortaleza-Ceará, on page https://fabricadeaplicativos.com.br and will be made available with an instrument composed of the Oswestry 2.0 Disability Index. Results: Explanatory screens for download and access to the application that was developed to facilitate the reach of relevant information to the elderly who suffer limitations in their day-to-day coming from the aging process. Conclusion: Having seen that there are few studies and applications on this subject, it is necessary to create an application focused on the subject.(AU)
Introducción: La discapacidad funcional y el rendimiento físico se definen por la dificultad o necesidad de ayuda del individuo para realizar las tareas diarias, lo que puede repercutir en la capacidad adaptativa de las actividades diarias, tanto en sus capacidades físicas como mentales. El proceso de envejecimiento conduce a una discapacidad funcional, comprometiendo la calidad de vida. Objetivo general: Construir una aplicación de salud centrada en la salud de personas mayores con discapacidad lumbar. Métodos: Se trata de un estudio del tipo constructivo de una aplicación, desarrollado durante el período de agosto de 2021 a mayo de 2022 en Fortaleza-CE, en la página https://fabricadeaplicativos.com.br y estará disponible con un instrumento compuesto. por el Índice de Discapacidad Oswestry 2.0. Resultados: Pantallas explicativas de descarga y acceso a la aplicación desarrollada para facilitar el acceso a información relevante a personas mayores que sufren limitaciones en su vida diaria, derivadas del proceso de envejecimiento. Conclusión: Dado que existen pocos estudios y aplicaciones sobre este tema, es necesario crear una aplicación enfocada en el tema.(AU)
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Anciano , Dolor , Envejecimiento , Ejercicio Físico , Ciencia, Tecnología y SociedadRESUMEN
BACKGROUND: There is some evidence indicating that inflammation of the aneurysmal wall is related to aneurysmal growth and rupture. The presence of CD68 may indicate greater inflammatory activity. The objective of this study is to evaluate CD68 immunoexpression in surgically resected brain aneurysms and its association with smoking. METHODS: The resected brain aneurysmal walls after microsurgical clipping were envoyed to immunohistochemistry investigation. The objective was to evaluate the expression of CD68 and CD34 antibodies. The associations between inflammatory markers, smoking, and rupture were tested using Fischer's exact test. RESULTS: CD68 immunoexpression in the tunica media was associated with larger aneurysms: 7.0 mm (7.0-9.0 mm) versus 5.0 mm (3.5-5 mm; p = 0.011). There was no statistically significant association between smoking and CD68 expression in the tunica media (p = 0.234) or in either the tunica media or the tunica intima (p = 0.628). There was also no statistically significant association between hemorrhagic presentation of the aneurysm and CD68 expression in the tunica media (p = 0.689) or in either the tunica media or the tunica intima (p = 0.348). Therefore, the presence of CD68-positive cells in the aneurysmal walls indicates an association with size, especially if the tunica media is exclusively compromised (p = 0.011). CONCLUSION: Immunohistochemistry investigation for CD68 antibodies was used to determine histiocytic infiltration. Adequately powered studies are necessary to further investigate the association between CD68-positive cells and both smoking history and hemorrhagic presentation of aneurysms.
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Intramedullary tumors represent the major cause of spinal cord injuries, and its symptoms include pain and weakness. Progressive weakness may concomitantly occur in the upper and lower limbs, along with lack of balance, spine tenderness, sensory loss, trophic changes of extremity, hyperreflexia, and clonus. The study protocol was in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. A systematic search of the MEDLINE electronic database was performed to identify the studies reporting the clinical features of children and adults who presented with an intramedullary lymphoma. Twenty-one studies were included, reporting 25 cases. Manuscripts were excluded if the full-text article was not available, original data were not reported (e.g., review articles), or if the main disease was not intramedullary lymphoma. A structured data extraction form was employed to standardize the identification and retrieval of data from manuscripts. To enlighten the discussion, a case is also presented. An 82-year-old woman with Fitzpatrick skin type II, diagnosed and treated for non-Hodgkin's lymphoma 7 years ago, was admitted with mental confusion and memory loss for the past 2 months-evolving with recurring falls from her own height. One day before admission, she displayed Brown-Séquard syndrome. An expansive lesion from C2 to C4 in the cervical spinal cord was found and a hypersignal spinal cord adjacent was described at the bulb medullary transition to the C6-C7 level. A primary spinal cord tumor was considered, as well as a melanoma metastasis, due to the lesion's flame pattern. The patient presented a partial recovery of symptoms and a reduction of the spinal cord edema after being empirically treated with corticosteroids, but the lesion maintained its extent. Subsequently, a large diffuse B-cell lymphoma with nongerminal center was found in open body biopsy, infiltrating neural tissue. The main objective of the present study is to report a surgical case treated for a large diffuse B-cell lymphoma, in addition to presenting the results of a systematic review of primary intramedullary spinal cord lymphoma.
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BACKGROUND: Asymptomatic visceral leishmaniasis (VL) infection is a risk for transfusion safety. Leukoreduction has been an alternative for the prevention of some blood-borne diseases, including VL. This study aimed to evaluate the role of leukoreduction of cellular blood components as a control measure for transfusional VL transmission. RESEARCH DESIGN AND METHODS: A total of 161 polytransfused patients with non-leukoreduced blood components (HNL), 95 polytransfused with leukoreduced blood components (LH), and 202 non-transfused (NT) from endemic regions for VL and with a similar epidemiological profile. The detection of antibodies against VL was performed by ELISA and the presence of the parasite was investigated by real-time PCR. Statistical significance was defined as p < .05. RESULTS: When comparing three groups, ELISA results were statistically significant (p = .0065). The residual analysis of ELISA showed statistically significant for the HNL group compared to the general group (p = .002; OR: 5.6; CI: 1.7-25.8), demonstrating that individuals who received non-leukoreduced transfusions are five times more likely to acquire Leishmania infantum infection than the general. DISCUSSION: Higher prevalence in the group with HNL and low prevalence in those who received LH, similar to NT patients, highlight the risk of transfusional VL transmission and reinforce the role of leukoreduction in its prevention.
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Leishmania infantum , Leishmaniasis Visceral , Humanos , Leishmaniasis Visceral/epidemiología , Leishmaniasis Visceral/prevención & control , Anticuerpos , Infecciones Asintomáticas , Ensayo de Inmunoadsorción Enzimática , Reacción en Cadena en Tiempo Real de la PolimerasaRESUMEN
BACKGROUND: Trigeminal neuralgia (TN) is a neuropathic pain that affects one or more branches of the trigeminal nerve. Surgical options after pharmacological failure are Microvascular Decompression (MVD) or percutaneous procedures, which include Balloon Compression (PBC). This study aims to describe pain outcomes and complications after PBC and MVD procedures for patients with trigeminal neuralgia. METHODS: We performed a systematic review and meta-analysis on PubMed, EMBASE, LILACS, and Web of Science databases up to April 2022, following PRISMA guidelines (Preferred Reporting Items for Systematic Reviews and meta-Analysis). Articles that separately describe pain outcome for MVD and PBC were included. MINORS tool was used for bias assessment. Meta-analysis results are presented in forest plot and funnel plot. RESULTS: 853 studies were assessed for screening, and 11 studies met the inclusion criteria for this review. A total of 1046 patients underwent PBC and 1324 underwent MVD. The subgroup analysis for patients without multiple sclerosis shows that MVD was associated with lower number of patients with pain than PBC, with an OR value of 0.54 (95 % CI 0.34-0.84). All other analyses evidenced a tendency for better outcomes after the MVD procedure, but with no statistically significant difference. CONCLUSION: Considering short and long pain relief, recurrence of pain and total complications for MVD and PBC, our study found that MVD is the best surgical option available for trigeminal neuralgia.
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Oclusión con Balón , Cirugía para Descompresión Microvascular , Neuralgia del Trigémino , Humanos , Neuralgia del Trigémino/cirugía , Cirugía para Descompresión Microvascular/métodos , Resultado del Tratamiento , Dolor/cirugía , Oclusión con Balón/métodos , Estudios RetrospectivosRESUMEN
OBJECTIVE: The authors searched for genetic and transcriptional signatures associated with tumor progression and recurrence in their cohort of patients with meningiomas, combining the analysis of targeted exome, NF2-LOH, transcriptome, and protein expressions. METHODS: The authors included 91 patients who underwent resection of intracranial meningioma at their institution between June 2000 and November 2007. The search of somatic mutations was performed by Next Generation Sequencing through a customized panel and multiplex ligation-dependent probe amplification for NF2 loss of heterozygosity. The transcriptomic profile was analyzed by QuantSeq 3' mRNA-Seq. The differentially expressed genes of interest were validated at the protein level analysis by immunohistochemistry. RESULTS: The transcriptomic analysis identified an upregulated set of genes related to metabolism and cell cycle and downregulated genes related to immune response and extracellular matrix remodeling in grade 2 (atypical) meningiomas, with a significant difference in recurrent compared with nonrecurrent cases. EZH2 nuclear positivity associated with grade 2, particularly with recurrent tumors and EZH2 gene expression level, correlated positively with the expression of genes related to cell cycle and negatively to genes related to immune response and regulation of cell motility. CONCLUSIONS: The authors identified modules of dysregulated genes in grade 2 meningiomas related to the activation of oxidative metabolism, cell division, cell motility due to extracellular remodeling, and immune evasion that were predictive of survival and exhibited significant correlations with EZH2 expression.
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Neoplasias Meníngeas , Meningioma , Humanos , Meningioma/cirugía , Neoplasias Meníngeas/cirugía , Recurrencia Local de Neoplasia/patología , Ciclo Celular , División Celular , Proteína Potenciadora del Homólogo Zeste 2/genéticaRESUMEN
Primary central nervous system lymphoma (PCNSL) is an uncommon lymphoproliferative disease associated with immunosuppression. Here, we report the case of a patient with multiple sclerosis, under treatment with fingolimod (FTY720, Gilenya) for 4 years, who developed this condition. Although the causal relationship cannot be established, there are cases in the literature that describe the appearance of lymphoma after the use of this medication. Considering the high mortality of PCNSL, epidemiological studies are necessary to establish a relationship between its arising and the use of immunosuppressants.
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Linfoma , Esclerosis Múltiple , Humanos , Clorhidrato de Fingolimod/efectos adversos , Esclerosis Múltiple/complicaciones , Esclerosis Múltiple/tratamiento farmacológico , Esclerosis Múltiple/patología , Inmunosupresores/efectos adversos , Linfoma/inducido químicamente , Linfoma/complicaciones , Linfoma/tratamiento farmacológico , Sistema Nervioso Central/patologíaRESUMEN
INTRODUCTION: Life expectancy in individuals has increased in recent years. There is no consensus in the literature on the best treatment for a ruptured aneurysm in the elderly (> 60 years), but some places only have microsurgery as a therapeutic strategy. This work aims to develop a prognostic scale for ruptured intracranial aneurysms in the elderly. MATERIAL AND METHODS: Two thousand five hundred thirty patients with subarachnoid hemorrhage were retrospectively evaluated in the last ten years, and 550 of them were elderly. We developed a prognostic scale from the analysis of medical records, clinical and tomographic features that had statistical significance. Glasgow Coma Outcome (GOS) was the outcome of interest and p value < 0,05 was considered statistically significant. RESULTS: Five hundred fifty patients were evaluated, and the comorbidities that were independent variables for poor prognosis were smoking and arterial hypertension; clinical variables were Hunt-Hess, modified Rankin and Glasgow Coma Scale; tomographic was Fisher scale. Poor outcome was defined as GOS ≤ 3. Poor surgical outcomes were more remarkable in the high-risk factor categories, being 6.41 times higher among individuals who had 3 to 4 risk factors and 8.80 times higher among individuals with 5 to 6 risk factors. CONCLUSION: In some vascular neurosurgery services worldwide, microsurgery is the only therapeutic option. This scale aimed at the elderly patient individualizes the treatment and can predict the clinical outcome in ruptured intracranial aneurysms.
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Aneurisma Roto , Aneurisma Intracraneal , Hemorragia Subaracnoidea , Humanos , Anciano , Aneurisma Intracraneal/cirugía , Aneurisma Intracraneal/complicaciones , Estudios Retrospectivos , Microcirugia/efectos adversos , Microcirugia/métodos , Resultado del Tratamiento , Hemorragia Subaracnoidea/cirugía , Hemorragia Subaracnoidea/etiología , Aneurisma Roto/cirugía , Aneurisma Roto/complicacionesRESUMEN
Objectives The aim of the present study is to analyze if aquaporin-4 (AQP4) may also be a tumor progression marker for meningiomas. Methods This is an immunohistochemistry study realized at the Universidade de São Paulo, São Paulo, state of São Paulo, Brazil: frozen meningioma samples from 81 patients (57 females and 24 males, age range from 22 to 81 years old, average 56.5 14.1 years old), including 57 meningiomas World Health Organization (WHO) grade I (GI); 19 grade II (GII), and 5 grade III (GIII) were analyzed. The relative expression level of AQP4 was analyzed by quantitative polymerase chain reaction (qPCR), using the SYBR Green approach and for staining detection. Tissue sections were routinely processed and subjected to antigen retrieval. Results The expression of AQP4 in meningioma samples ranged from 0 to 10.26, with a median of 0.001 in GI cases, of 0.008 in GII cases, and of 0.006 in GIII cases. Although not statistically significant (p » 0.942), GI meningiomas have a lower median AQP4 expression level than higher malignant grade cases. Conclusion The AQP4 gene and protein expressions presented no association with meningioma malignant progression.
Objetivo O objetivo do presente estudo é analisar se a aquaporina-4 (AQP4) também pode ser um marcador de progressão tumoral para meningiomas. Métodos Trata-se de um estudo imunohistoquímico realizado na Universidade de São Paulo, SP, Brasil. Amostras congeladas de meningioma de 81 pacientes (57 mulheres e 24 homens, faixa etária de 22 a 81 anos, média de 56,5 14,1 anos), incluindo 57 meningiomas grau I (GI) da Organização Mundial da Saúde (OMS); 19 grau II (GII) e 5 grau III (GIII) foram analisados. O nível de expressão relativa de AQP4 foi analisado por reação em cadeia de polimerase quantitativa (qPCR, sigla em inglês), usando a abordagem SYBR Green e para detecção de manchas. As seções de tecido foram rotineiramente processadas e sujeitas a recuperação de antígeno. Resultados A expressão de AQP4 em amostras de meningioma variou de 0 a 10,26, com mediana de 0,001 nos casos GI; 0,008 nos casos GII; e 0,006 nos casos GIII. Embora não sejam estatisticamente significantes (p » 0,942), os meningiomas GI apresentam mediana mais baixa do nível de expressão de AQP4 do que os casos de grau maligno mais alto. Conclusão Expressões de genes e proteínas AQP4 apresentadas na associação com progressão maligna do meningioma.
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Background Aquaporins (AQPs) are a family of membrane proteins that regulate the osmotic permeability of the plasma membrane. There are described in the literature a total of 13 types of Aquaporins in mammals, each with different places of expression. In addition to water, some AQPs allow the passage of glycerol and ammonia, being called Aquaglyceroproteins. In the central nervous system, AQPs 1 and 4 are expressed, being responsible for the water regulation in the blood-brain barrier. These two AQPs are believed to participate in the pathophysiological process that governs the behavior of various CNS diseases, such as trauma and primary tumors. More particularly, there are quite controversial data in the literature on the expression of AQP4 in tumors and its relationship with disease progression and treatment possibility. Objective This paper aims to perform a literature review on the function and expression of AQP4 in the CNS and primary tumors of this system, to compile what is in the literature on the subject and raise new possible research hypotheses. Methods The PUBMED platform was used for bibliographic survey using "Aquaporin 4," "expression" and "astrocytomas" as keywords. Articles older than 2008 and articles that did not address AQP4 expression in astrocytomas were excluded. In the selected articles, the following topics were investigated: AQP4 structure, brain and tumor localization, and relationship with peritumoral edema. Results Regarding the structure and location of AQP4, the literature presents two isoforms of AQP4: M1 and M23. Both form clusters of AQP4 called "orthogonal arrays of proteins - OAPs." In the tumor tissue, the literature shows a decrease in the formation of OAPs and an increase in the expression of both AQP4 isoforms, besides losing their polarity, diffusing through the cytoplasmic membrane. As for the function of AQP4 in tumors, AQP4 assists in cell migration and invasion, in addition to participating in cell proliferation and apoptosis. Regarding the relationship with cerebral edema, there are controversial knowledge. Studies have shown that increased AQP4 aggravates cytotoxic edema of tumor cells and, by assisting in cell migration and angiogenesis, indirectly assist in the formation of vasogenic edema by breaking the blood-brain barrier. Other studies, however, point to the increase in AQP4 as a protective mechanism to combat vasogenic edema that occurs in tumor formation. Furthermore, the literature presents a therapeutic proposal in which, by inhibiting AQP4 expression, tumor migration and cerebral edema decrease in rats with glioblastoma. Discussion As shown in the literature, there is a difference in histopathological structure between high and low grade gliomas. However, there are common changes between them. These common changes could then be used as a factor of severity or evolution of low-grade to high-grade tumors. Moreover, it is not yet possible to perceive the true relationship of AQP4 expression and increased VEGF evolution of peritumoral edema. Finally, it can be hypothesized that since the expression ratio between AQP4 isoforms in normal tissue is greater than in some tumors, the decrease in this ratio is due either to decreased M23 expression or increased of the isoform M1. Conclusion Further studies are needed to understand the physiology and pathophysiology involving AQP4 in astrocytomas to create effective therapeutic proposals to combat this disease.
Introdução As aquaporinas (AQPs) são uma família de proteínas de membrana que regulam a permeabilidade osmótica da membrana plasmática. Existem descritos na literatura um total de 13 tipos de aquaporinas em mamíferos, cada um com diferentes locais de expressão. Além da água, alguns AQPs permitem a passagem de glicerol e amônia, sendo chamados de aquagliceroproteínas. No sistema nervoso central, as AQPs 1 e 4 são expressas, sendo responsáveis pela regulação da água na barreira hematoencefálica. Acredita-se que esses dois AQPs participem do processo fisiopatológico que regula o comportamento de várias doenças do SNC, como trauma e tumores primários. Mais particularmente, há dados bastante controversos na literatura sobre a expressão de AQP4 em tumores e sua relação com a progressão da doença e possibilidade de tratamento. Objetivo Este artigo tem como objetivo realizar uma revisão da literatura sobre a função e expressão da AQP4 no SNC e tumores primários deste sistema, a fim de compilar o que está na literatura sobre o assunto e levantar novas hipóteses de pesquisa possíveis. Método A plataforma PUBMED foi utilizada para levantamento bibliográfico utilizando "Aquaporin 4," "expression" e "astrocitomas" como palavras-chave. Artigos com idade superior a 2008 e artigos que não abordaram a expressão de AQP4 em astrocitomas foram excluídos. Nos artigos selecionados, foram investigados os seguintes tópicos: estrutura da AQP4, localização do cérebro e do tumor e relação com o edema peritumoral. Resultados Em relação à estrutura e localização da AQP4, a literatura apresenta duas isoformas da AQP4: M1 e M23. Ambos formam aglomerados de AQP4 chamados "arranjos ortogonais de proteínas - OAPs." No tecido tumoral, a literatura mostra uma diminuição na formação de OAPs e um aumento na expressão de ambas as isoformas AQP4, além de perder sua polaridade, difundindo através da membrana citoplasmática. Quanto à função da AQP4 nos tumores, a AQP4 auxilia na migração e invasão celular, além de participar da proliferação celular e apoptose. Em relação à relação com o edema cerebral, existem controvérsias. Estudos demonstram que o aumento da AQP4 agrava o edema citotóxico das células tumorais e, auxiliando na migração celular e na angiogênese, auxilia indiretamente na formação de edema vasogênico por quebra da barreira hematoencefálica. Outros estudos, no entanto, apontam para o aumento da AQP4 como mecanismo protetor para combater o edema vasogênico que ocorre na formação de tumores. Além disso, a literatura apresenta uma proposta terapêutica em que, ao inibir a expressão da AQP4, a migração tumoral e o edema cerebral diminuem em ratos com glioblastoma. Discussão Como mostrado na literatura, há uma diferença na estrutura histopatológica entre os gliomas de alto e baixo grau. No entanto, existem mudanças comuns entre eles. Estas alterações comuns poderiam então ser usadas como um fator de gravidade ou evolução de tumores de baixo grau a alto grau. Além disso, ainda não é possível perceber a verdadeira relação entre a expressão da AQP4 e o aumento da evolução do VEGF no edema peritumoral. Finalmente, pode-se supor que, como a razão de expressão entre as isoformas de AQP4 no tecido normal é maior do que em alguns tumores, a diminuição dessa razão é devida à diminuição da expressão de M23 ou ao aumento da isoforma M1. Conclusão: Novos estudos são necessários para compreender a fisiologia e a fisiopatologia da AQP4 em astrocitomas, a fim de criar propostas terapêuticas efetivas para combater essa doença.
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Background: The surgical ressection of petroclival meningiomas is challenging due to its deep location and relationship with vital neurovascular structures. Usually they are benign injuries, but they can involve or infiltrate skull base bones, dura mater and brainstem. This makes the total removing very difficult or impossible without causing neurological deficits. The objective of this study is to review the surgical approaches used on the treatment of petroclival meningiomas and the knowledge which we achieved upon the surgical management of 30 cases. Methods: Series of 30 petroclival meningioma-cases. In the beginning of our series we used petrous approach for all the cases, however, with the acquiring of experience, we are indicating the retrosigmoid approach, leaving the petrous and skull-orbito-zigomatics approaches for selected cases. Results: Owing to the difficulty of the access, the petroclival meningiomas usually require different surgical approaches and have distint surgical difficulties. There are three main approaches: fronto-orbito-zigomatics and variants; petrous and variants and retrosigmoid, and they can be combined. The choice for a surgical approach is usually on the location and size of the tumor, on the skull shape, the involvement of venous structures and according to the surgeon´s experience. Conclusion: Petroclival meningiomas are rare and complex on the skull base. The adequate choice is crucial to achieve the good surgical result.
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Background: Parasagittal meningioma (PSM) is a tumor located in the parasagittal angle which extends to and/ or invades the superior sagittal sinus (SSS). Surgical resection of the PSM, the standard treatment in such cases, poses a challenge for neurosurgery, particularly where there is an invasion of the SSS. This is due to the risk of complications through injury to the adjacent vascular structures. The objective of the study was to perform a comparative evaluation of the surgical techniques for total resection of the PSM (Simpson Grade [SG] I and SG II), which present the highest rates of success in terms of the following variables: mortality, recurrence, and postoperative complications. Methods: Fifty-six patients undergoing resection surgery for PSM with the invasion of the SSS were enrolled. The patients were divided into two groups: Group A, comprising 26 cases of patients subjected to SG I PSM resection surgery and Group B, with 31 cases of patients subjected to SG II PSM resection surgery, with preservation of the SSS. Results: The results showed that Group B had lower rates of postoperative deficit (P = 0.026), zero mortality, and reduced recurrence. The use of complementary radiotherapy for atypical meningiomas (WHO II) in Group B was satisfactory in controlling the disease. Conclusion: The Simpson II, with preservation of the SSS, was better as it diminishes the vascular risks of surgery, reduces the frequency of severe postoperative deficit, and reduces mortality.
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INTRODUCTION: Miller-Fisher Syndrome (MFS) is a variant of Guillain-Barré syndrome (GBS), an acute immune-mediated neuropathy, which manifests as a rapidly evolving areflex motor paralysis. This syndrome presents as a classic triad: ophthalmoplegia, areflexia, and ataxia. MFS is usually benign and self-limited. CASE REPORT: A Caucasian patient was admitted to our hospital with the flu, loss of bilateral strength in the lower limbs and upper limbs and sudden-onset ataxia 7 days after receiving a first dose of the Oxford/AstraZeneca COVID-19 vaccine. On neurological examination, the patient had Glasgow Coma Scale score of 15, with absence of meningeal signs; negative Babinski sign; grade 2 strength in the lower limbs and grade 4 strength in the upper limbs; axial and appendicular cerebellar ataxia; and peripheral facial diparesis predominantly on the right, without conjugate gaze deviation. Cerebrospinal fluid (CSF) was collected on admission, and analysis revealed albuminocytological dissociation with CSF protein of 148.9 mg/dL; leukocytes, 1; chlorine, 122; glucose, 65 mg/mL; red cells, 2; and non-reactive venereal disease research laboratory test result. The COVID-19 IgG/IgM rapid immunological test was negative. Electroneuromyography revealed a recent moderate-grade and primarily sensory and motor demyelinating polyneuropathy with associated proximal motor block. DISCUSSION AND CONCLUSION: Miller-Fisher Syndrome may be related to events other than infections prior to neuropathy, as in the case reported here. The patient presented strong correlations with findings for MFS reported in the literature, such as the clinical condition, the results of electroneuromyography, and results of the CSF analysis typical for MFS. When treatment was provided as proposed in the literature, the disease evolved with improvement. Ultimately, the diagnosis of incomplete MFS was made, including acute ataxic neuropathy (without ophthalmoplegia).
Asunto(s)
COVID-19 , Síndrome de Miller Fisher , Oftalmoplejía , Humanos , Síndrome de Miller Fisher/diagnóstico , Vacunas contra la COVID-19 , Oftalmoplejía/etiología , Ataxia/complicacionesRESUMEN
Background: Most petroclival meningiomas are benign tumors, but their neurosurgical treatment is one of the greatest challenges in this field. Acquiring a deep practical knowledge of brain anatomy is the first step on the path to successfully meeting this challenge. To this end, the present paper is divided into two parts. The first regards the microsurgical anatomy and surgical approaches used in the management of petroclival meningiomas. The second correlates the brain anatomies of the 30 cases of petroclival meningiomas which the senior author (GRI) has operated on. Methods: Eight cadaver heads were dissected using surgical microscopes at the University of Arkansas microsurgery laboratory. The heads were stabilized in a Mayfield device to simulate surgical conditions and colored silicon was injected to highlight the differences between arteries and veins. The approaches performed were: cranio-orbital zygomatic, posterior and anterior petrosectomy, and retrosigmoid. Results: Three main surgical approaches were chosen to treat petroclival meningiomas: the pterional approach and its variants, the petrous approach and its variants, and the retrosigmoid approach. To rationalize the choice of approach, the clivus was separated into superior, middle, and inferior thirds. Conclusion: Several surgical approaches are useful in accessing the petroclival region. Acquiring a practical knowledge of this anatomy in a microsurgical laboratory is fundamental for any surgeon who intends to operate on petroclival meningiomas.
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BACKGROUND: Spinal cord stimulation (SCS) is traditionally performed by implanting surgical leads along the midline of the spinal cord, over the dorsal columns. Here, we present a patient who successfully underwent lateral cervical SCS to treat chronic refractory neuropathic pain. METHODS: A 46-year-old female, with a schwannoma involving the right axillary nerve, presented with a chronic refractory right upper extremity pain syndrome. The tumor was located between the fibers of the teres minor and the posterior deltoid, and measured 2.2 cm in diameter. After 8 months of analgesics, opioids, physiotherapy, and acupuncture, the patient underwent surgery; however, the tumor was unresectable (i.e., due to significant adjacent vascular/neural structures). Three months later, she had a midline C6-C7 laminectomy for placement of a right-sided epidural SCS lead (i.e., containing 16 electrode contacts). RESULTS: Within 4 days following this SCS procedure, the patient's pain completely resolved; at 10 postoperative months, she still remains pain free. CONCLUSION: Lateral SCS at the C6-C7 level provided a safe and effective option for the relief of chronic neuropathic pain attributed to an unresectable schwannoma of the right axillary nerve in a 46-year-old female.