Cisticercose intradural-extramedular cerebral e espinhal: relato de caso e revisão da literatura

Relato de um caso raro de apresentação de infestação por cisticercose do espaço subaracnóide cerebral e intra-raquiano nas regiões cervical e torácica em mulher de 59 anos de idade, com náuseas, sinais de ataxia cerebelar e perda gradual da sensibilidade nas pernas. O diagnóstico foi feito por meio de imagens por ressonância magnética do cérebro e da coluna cérvico-torácica, que evidenciaram a presença de cistos nos espaços subaracnóides. O exame do líquido cefalorraquiano revelou teste imunológico ELISA positivo e elevado nível de proteína (420 mg/dl), indicativo de atividade da doença. Os parasitos foram removidos cirurgicamente pela necessidade de descompressão da medula espinhal torácica. Breve comentário sobre a patogênese da forma cística da cisticercose espinhal intradural-extramedular, aspectos das imagens de ressonância magnética e tratamento foram feitos com base nos achados de revisão da literatura.

Extended Endoscopic Endonasal Approaches for Cerebral Aneurysms: Anatomical, Virtual Reality and Morphometric Study

Introduction. The purpose of the present contribution is to perform a detailed anatomic and virtual reality three-dimensional stereoscopic study in order to test the effectiveness of the extended endoscopic endonasal approaches for selected anterior and posterior circulation aneurysms. Methods. The study was divided in two main steps: (1) simulation step, using a dedicated Virtual Reality System (Dextroscope, Volume Interactions); (2) dissection step, in which the feasibility to reach specific vascular territory via the nose was verified in the anatomical laboratory. Results. Good visualization and proximal and distal vascular control of the main midline anterior and posterior circulation territory were achieved during the simulation step as well as in the dissection step (anterior communicating complex, internal carotid, ophthalmic, superior hypophyseal, posterior cerebral and posterior communicating, basilar, superior cerebellar, anterior inferior cerebellar, vertebral, and posterior inferior cerebellar arteries). Conclusion. The present contribution is intended as strictly anatomic study in which we highlighted some specific anterior and posterior circulation aneurysms that can be reached via the nose. For clinical applications of these approaches, some relevant complications, mainly related to the endonasal route, such as proximal and distal vascular control, major arterial bleeding, postoperative cerebrospinal fluid leak, and olfactory disturbances must be considered

Involvement of a transforming-growth-factor-beta-like molecule in tumor-cell-derived inhibition of nitric-oxide synthesis in cerebral endothelial cells.

Nitric oxide (NO) has been shown to exert cytotoxic effects on tumor cells. We have reported that EC219 cells, a rat-brain-microvessel-derived endothelial cell line, produced NO through cytokine-inducible NO synthase (iNOS), the induction of which was significantly decreased by (a) soluble factor(s) secreted by DHD/PROb, an invasive sub-clone of a rat colon-carcinoma cell line. In this study, the DHD/PROb cell-derived NO-inhibitory factor was characterized. Northern-blot analysis demonstrated that the induction of iNOS mRNA in cytokine-activated EC219 cells was decreased by PROb-cell-conditioned medium. When DHD/PROb cell supernatant was fractionated by affinity chromatography using Con A-Sepharose or heparin-Sepharose, the NO-inhibitory activity was found only in Con A-unbound or heparin-unbound fractions, respectively, indicating that the PROb-derived inhibitory factor was likely to be a non-glycosylated and non-heparin-binding molecule. Pre-incubation of DHD/PROb-cell supernatant with anti-TGF-beta neutralizing antibody completely blocked the DHD/PROb-derived inhibition of NO production by EC219 cells. Addition of exogenous TGF-beta 1 dose-dependently inhibited NO release by EC219 cells. The presence of active TGF-beta in the DHD/PROb cell supernatant was demonstrated using a growth-inhibition assay. Moreover, heat treatment of medium conditioned by the less invasive DHD/REGb cells, which constitutively secreted very low levels of active TGF-beta, increased both TGF-beta activity and the ability to inhibit NO production in EC219 cells. Thus, DHD/PROb colon-carcinoma cells inhibited NO production in EC219 cells by secreting a factor identical or very similar to TGF-beta.

Intervalos de referência do pico de velocidade sistólica da artéria cerebral média fetal na população brasileira

OBJETIVO: Determinar uma curva de referência baseada em múltiplos da mediana para o pico de velocidade sistólica da artéria cerebral média fetal. MATERIAIS E MÉTODOS: Realizou-se estudo de corte transversal com 143 gestantes normais entre 23 e 35 semanas. Realizou-se varredura bidimensional em corte axial do crânio fetal, incluindo os tálamos e o septo pelúcido, e em seguida acionou-se o modo color Doppler, visualizando-se a artéria cerebral média. O Doppler pulsátil foi disposto próximo à origem deste vaso, utilizando-se ângulo de insonação de menos de 20°. Para avaliar a correlação do pico de velocidade sistólica da artéria cerebral média com a idade gestacional, utilizou-se o coeficiente de correlação de Person (r). Por meio de modelos de regressão, construiu-se uma tabela de múltiplos da mediana para o pico de velocidade sistólica da artéria cerebral média em cada idade gestacional avaliada, e adicionalmente determinaram-se valores de referência para essa variável. RESULTADOS: Observou-se forte correlação entre o pico de velocidade sistólica da artéria cerebral média e a idade gestacional (r = 0,70; p = 0,001). Determinaram-se valores do pico de velocidade sistólica da artéria cerebral média para os seguintes múltiplos da mediana: 1,0; 1,29; 1,5; 1,55. Determinaram-se os percentis 2,5 e 97,5 para o pico de velocidade sistólica da artéria cerebral média, variando de 24,33 cm²/s a 78,36 cm²/s. CONCLUSÃO: Um nomograma do pico de velocidade sistólica da artéria cerebral média fetal foi determinado.

Cerebral oximetry and return of spontaneous circulation after cardiac arrest: A systematic review and meta-analysis.

AIM: The prediction of return of spontaneous circulation (ROSC) during resuscitation of patients suffering of cardiac arrest (CA) is particularly challenging. Regional cerebral oxygen saturation (rSO2) monitoring through near-infrared spectrometry is feasible during CA and could provide guidance during resuscitation. METHODS: We conducted a systematic review and meta-analysis on the value of rSO2 in predicting ROSC both after in-hospital (IH) or out-of-hospital (OH) CA. Our search included MEDLINE (PubMed) and EMBASE, from inception until April 4th, 2015. We included studies reporting values of rSO2 at the beginning of and/or during resuscitation, according to the achievement of ROSC. RESULTS: A total of nine studies with 315 patients (119 achieving ROSC, 37.7%) were included in the meta-analysis. The majority of those patients had an OHCA (n=225, 71.5%; IHCA: n=90, 28.5%). There was a significant association between higher values of rSO2 and ROSC, both in the overall calculation (standardized mean difference, SMD -1.03; 95%CI -1.39,-0.67; p<0.001), and in the subgroups analyses (rSO2 at the beginning of resuscitation: SMD -0.79; 95%CI -1.29,-0.30; p=0.002; averaged rSO2 value during resuscitation: SMD -1.28; 95%CI -1.74,-0.83; p<0.001). CONCLUSIONS: Higher initial and average regional cerebral oxygen saturation values are both associated with greater chances of achieving ROSC in patients suffering of CA. A note of caution should be made in interpreting these results due to the small number of patients and the heterogeneity in study design: larger studies are needed to clinically validate cut-offs for guiding cardiopulmonary resuscitation.

EEG as an Indicator of Cerebral Functioning in Postanoxic Coma.

Postanoxic coma after cardiac arrest is one of the most serious acute cerebral conditions and a frequent cause of admission to critical care units. Given substantial improvement of outcome over the recent years, a reliable and timely assessment of clinical evolution and prognosis is essential in this context, but may be challenging. In addition to the classic neurologic examination, EEG is increasingly emerging as an important tool to assess cerebral functions noninvasively. Although targeted temperature management and related sedation may delay clinical assessment, EEG provides accurate prognostic information in the early phase of coma. Here, the most frequently encountered EEG patterns in postanoxic coma are summarized and their relations with outcome prediction are discussed. This article also addresses the influence of targeted temperature management on brain signals and the implication of the evolution of EEG patterns over time. Finally, the article ends with a view of the future prospects for EEG in postanoxic management and prognostication.

Tómese unos minutos para revisar sus conocimientos sobre: Enfermedad cerebrovascular/circulación cerebral

1. ¿Cuál de las siguientes arterias no forma parte del territorio carotídeo? a. Arteria cerebral posterior, b. Carótida interna, c. Arteria cerebral media, d. Arteria ...

Imaging the time-integrated cerebral metabolic activity with subcellular resolution through nanometer-scale detection of biosynthetic products deriving from (13)C-glucose.

Glucose is the primary source of energy for the brain but also an important source of building blocks for proteins, lipids, and nucleic acids. Little is known about the use of glucose for biosynthesis in tissues at the cellular level. We demonstrate that local cerebral metabolic activity can be mapped in mouse brain tissue by quantitatively imaging the biosynthetic products deriving from [U-(13)C]glucose metabolism using a combination of in situ electron microscopy and secondary ion mass-spectroscopy (NanoSIMS). Images of the (13)C-label incorporated into cerebral ultrastructure with ca. 100nm resolution allowed us to determine the timescale on which the metabolic products of glucose are incorporated into different cells, their sub-compartments and organelles. These were mapped in astrocytes and neurons in the different layers of the motor cortex. We see evidence for high metabolic activity in neurons via the nucleus (13)C enrichment. We observe that in all the major cell compartments, such as e.g. nucleus and Golgi apparatus, neurons incorporate substantially higher concentrations of (13)C-label than astrocytes.

Diagnóstico por imagem e aspectos clínicos da trombose venosa cerebral em recém-natos a termo sem dano cerebral: revisão em 10 anos

OBJETIVO: Descrever e comparar os métodos de imagem e os aspectos clínicos em quatro recém-natos a termo diagnosticados como trombose venosa cerebral, sem dano encefálico, adscritos a uma unidade de terapia intensiva neonatal. MATERIAIS E MÉTODOS: Revisão em 10 anos com quatro casos diagnosticados como trombose venosa cerebral por meio de ultrassonografia transfontanela com Doppler e confirmados por ressonância magnética/angiorressonância, correlacionados aos aspectos clínicos e evolução neurológica. RESULTADOS: A ultrassonografia foi normal em 75% dos casos e a ressonância magnética, em 100%. No caso alterado, a dilatação venosa foi identificada. O Doppler e a angiorressonância estavam alterados em 100% dos casos. Dos aspectos clínicos, a hipóxia (100%) e a convulsão precoce (100%) predominaram, com potencial evocado alterado em 50% dos casos. Na avaliação do neurodesenvolvimento, todas as áreas estiveram dentro da normalidade até a última avaliação. CONCLUSÃO: A ultrassonografia associada ao Doppler é capaz de identificar as alterações da trombose venosa cerebral, devendo ser complementada com a ressonância magnética, que é o padrão ouro de diagnóstico.

A probable dual mode of action for both L- and D-lactate neuroprotection in cerebral ischemia.

Lactate has been shown to offer neuroprotection in several pathologic conditions. This beneficial effect has been attributed to its use as an alternative energy substrate. However, recent description of the expression of the HCA1 receptor for lactate in the central nervous system calls for reassessment of the mechanism by which lactate exerts its neuroprotective effects. Here, we show that HCA1 receptor expression is enhanced 24 hours after reperfusion in an middle cerebral artery occlusion stroke model, in the ischemic cortex. Interestingly, intravenous injection of L-lactate at reperfusion led to further enhancement of HCA1 receptor expression in the cortex and striatum. Using an in vitro oxygen-glucose deprivation model, we show that the HCA1 receptor agonist 3,5-dihydroxybenzoic acid reduces cell death. We also observed that D-lactate, a reputedly non-metabolizable substrate but partial HCA1 receptor agonist, also provided neuroprotection in both in vitro and in vivo ischemia models. Quite unexpectedly, we show D-lactate to be partly extracted and oxidized by the rodent brain. Finally, pyruvate offered neuroprotection in vitro whereas acetate was ineffective. Our data suggest that L- and D-lactate offer neuroprotection in ischemia most likely by acting as both an HCA1 receptor agonist for non-astrocytic (most likely neuronal) cells as well as an energy substrate.

Cerebral Lactate Metabolism After Traumatic Brain Injury.

Cerebral energy dysfunction has emerged as an important determinant of prognosis following traumatic brain injury (TBI). A number of studies using cerebral microdialysis, positron emission tomography, and jugular bulb oximetry to explore cerebral metabolism in patients with TBI have demonstrated a critical decrease in the availability of the main energy substrate of brain cells (i.e., glucose). Energy dysfunction induces adaptations of cerebral metabolism that include the utilization of alternative energy resources that the brain constitutively has, such as lactate. Two decades of experimental and human investigations have convincingly shown that lactate stands as a major actor of cerebral metabolism. Glutamate-induced activation of glycolysis stimulates lactate production from glucose in astrocytes, with subsequent lactate transfer to neurons (astrocyte-neuron lactate shuttle). Lactate is not only used as an extra energy substrate but also acts as a signaling molecule and regulator of systemic and brain glucose use in the cerebral circulation. In animal models of brain injury (e.g., TBI, stroke), supplementation with exogenous lactate exerts significant neuroprotection. Here, we summarize the main clinical studies showing the pivotal role of lactate and cerebral lactate metabolism after TBI. We also review pilot interventional studies that examined exogenous lactate supplementation in patients with TBI and found hypertonic lactate infusions had several beneficial properties on the injured brain, including decrease of brain edema, improvement of neuroenergetics via a "cerebral glucose-sparing effect," and increase of cerebral blood flow. Hypertonic lactate represents a promising area of therapeutic investigation; however, larger studies are needed to further examine mechanisms of action and impact on outcome.

Is there any influence of breastfeeding on the cerebral blood flow? A review of 256 healthy newborns

OBJECTIVE: To investigate whether breastfeeding influence the cerebral blood-flow velocity. MATERIALS AND METHODS: The present study included 256 healthy term neonates, all of them with appropriate weight for gestational age, 50.8% being female. Pulsatility index, resistance index and mean velocity were measured during breastfeeding or resting in the anterior cerebral artery, in the left middle cerebral artery, and in the right middle cerebral artery of the neonates between their first 10 and 48 hours of life. The data were analyzed by means of a paired t-test, Brieger's f-test for analysis of variance and linear regression, with p < 0.01 being accepted as statistically significant. RESULTS: Mean resistance index decreased as the mean velocity increased significantly during breastfeeding. Pulsatility index values decreased as much as the resistance index, but in the right middle cerebral artery it was not statistically significant. CONCLUSION: Breastfeeding influences the cerebral blood flow velocities.

Cavernous sinus syndrome due to rhino-orbital-cerebral mucormycosis

The present report describes the case of a 43-year-old diabetic patient with facial pain, protruding eyes, nasal congestion and decreased right vision (involvement of the ipsilateral cranial nerves III, IV and V). Computed tomography showed diffuse sinusitis at right, cribriform plate erosion and presence of a hypodense collection in the frontal lobe with peripheral enhancement. Magnetic resonance imaging confirmed the presence of a cerebral abscess. Samples were collected from the lesion, confirming hyphae compatible with mucormycosis.

Evaluation of occupational and patient dose in cerebral angiography procedures

Objective The present study was aimed at estimating the doses received by physicians and patients during cerebral angiography procedures in a public hospital of Recife, PE, Brazil. Materials and Methods The study sample included 158 adult patients, and during the procedures the following parameters were evaluated: exposure parameters (kV, mAs), number of acquired images, reference air kerma value (Ka,r) and air kerma-area product (PKA). Additionally, the physicians involved in the procedures were evaluated as for absorbed dose in the eyes, thyroid, chest, hands and feet. Results The results demonstrated that the doses to the patients' eyes region were relatively close to the threshold for cataract occurrence. As regards the physicians, the average effective dose was 2.6 µSv, and the highest effective dose recorded was 16 µSv. Conclusion Depending on the number of procedures, the doses received by the physicians may exceed the annual dose limit for the crystalline lenses (20 mSv) established by national and international standards. It is important to note that the high doses received by the physicians are due to the lack of radiation protection equipment and accessories, such as leaded curtains, screens and protective goggles.