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A lo largo de la historia, el conocimiento sobre las meninges ha evolucionado desde los primeros registros en el papiro de Edwin Smith hasta la actualidad, donde se ha descrito SLYM, una cuarta meninge que separa el espacio subaracnoideo en un compartimiento superficial y otro profundo, a la que se le atribuyen funciones de barrera semipermeable y de nicho de células inmunes para la vigilancia y protección del sistema nerviosos central. La FIPAT contiene un grupo de terminologías que son mundialmente aceptadas para la descripción de las estructuras del cuerpo humano, sin embargo, en Terminologia Anatomica, Ter- minologia Neuroanatomica y Terminologia Histologica, aún no se encuentra incluido el término SLYM para representar una cuarta meninge, quizás porque sea un reciente descubrimiento. El objetivo de este estudio fue sugerir un nuevo término que concuerde con los lineamientos de la FIPAT y con las reglas de Terminología Anatómica Regular (RAT) en reemplazo de SLYM, además de proponer su inclusión en Terminologia Anatomica, Terminologia Neuroanatomica y Terminologia Histologica, previa revisión y aprobación por parte del comité respectivo de la FIPAT. Se revisó el acrónimo SLYM y los elementos que lo conforman (membrana subaracnoidea de tipo linfática), desde un enfoque etimológico, este análisis estuvo acompañado de una revisión a las reglas RAT aceptadas por la FIPAT, que fueron consideradas para examinar su cumplimiento por parte del acrónimo SLYM. Se encontró que SLYM, al igual que los términos que lo componen no cumplen totalmente con las reglas RAT. El acrónimo SLYM no proporciona una descripción adecuada de la estructura que representa, lo que contradice las reglas RAT. Se propone el término Suprapiamater como alternativa, para su inclusión en Terminologia Anatomica, Terminologia Neuroanatomica y Terminologia Histologica, basado en elementos latinos que describen su ubicación y función, mejorando la precisión y claridad en la comunicación científica.

SUMMARY: Throughout history, knowledge about the meninges has evolved from the first records in the Edwin Smith papyrus to the present, where SLYM, a fourth meninge that separates the subarachnoid space into a superficial compartment and another, has been described deep, to which semipermeable barrier and immune cell niche functions are attributed for the surveillance and protection of the central nervous system. The FIPAT contains a group of terminologies that are globally accepted for the description of the structures of the human body, however, in Terminologia Anatomica, Terminologia Neuroanatomica and Terminologia Histologica, the term SLYM to represent a fourth meninge is not yet included, perhaps because be a recent discovery. The objective of this study was to suggest a new term that agrees with the FIPAT guidelines and with the Regular Anatomical Terminology (RAT) rules to replace SLYM, in addition to proposing its inclusion in Terminologia Anatomica, Terminologia Neuroanatomica and Terminologia Histologica, previously review and approval by the respective FIPAT committee. The acronym SLYM and the elements that make it up (Subarachnoid Lymphatic-like Membrane) were reviewed from an etymological approach. This analysis was accompanied by a review of the RAT rules accepted by FIPAT, which were considered to examine their compliance by the acronym SLYM. It was found that SLYM, like the terms that compose it, do not fully comply with the RAT rules. The SLYM acronym does not provide an adequate description of the structure it represents, which contradicts the RAT rules. The term suprapiamater is proposed as an alternative, for inclusion in Terminologia Anatomica, Terminologia Neuroanatomica and Terminologia Histologica, based on Latin elements that describe its location and function, improving precision and clarity in scientific communication.

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The mechanisms underlying regeneration of the central nervous system (CNS) following lesions have been studied extensively in both vertebrate and invertebrate models. To shed light on regeneration, ascidians, a sister group of vertebrates and with remarkable ability to regenerate their brains, constitute an appropriate model system. Glial cells have been implicated in regeneration in vertebrates; however, their role in the adult ascidian CNS regeneration is unknown. A model of degeneration and regeneration using the neurotoxin 3-acetylpyridine (3AP) in the brain of the ascidian Styela plicata was used to identify astrocyte-like cells and investigate their role. We studied the CNS of control ascidians (injected with artificial sea water) and of ascidians whose CNS was regenerating (1 and 10 days after the injection with 3AP). Our results show that the mRNA of the ortholog of glutamine synthetase (GS), a glial-cell marker in vertebrates, is increased during the early stages of regeneration. Confirming the identity of GS, the protein was identified via immunostaining in a cell population during the same regeneration stage. Last, a single ortholog of GS (GSII) is present in ascidian and amphioxus genomes, while two types exist in fungi, some invertebrates, and vertebrates, suggesting that ascidians have lost the GSI type. Taken together, our findings revealed that a cell population expressing glial-cell markers may play a role in regeneration in adult ascidians. This is the first report of astrocyte-like cells in the adult ascidian CNS, and contributes to understanding of the evolution of glial cells among metazoans.

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A main goal in neuroscience is to understand the computations carried out by neural populations that give animals their cognitive skills. Neural network models allow to formulate explicit hypotheses regarding the algorithms instantiated in the dynamics of a neural population, its firing statistics, and the underlying connectivity. Neural networks can be defined by a small set of parameters, carefully chosen to procure specific capabilities, or by a large set of free parameters, fitted with optimization algorithms that minimize a given loss function. In this work we alternatively propose a method to make a detailed adjustment of the network dynamics and firing statistic to better answer questions that link dynamics, structure, and function. Our algorithm-termed generalised Firing-to-Parameter (gFTP)-provides a way to construct binary recurrent neural networks whose dynamics strictly follows a user pre-specified transition graph that details the transitions between population firing states triggered by stimulus presentations. Our main contribution is a procedure that detects when a transition graph is not realisable in terms of a neural network, and makes the necessary modifications in order to obtain a new transition graph that is realisable and preserves all the information encoded in the transitions of the original graph. With a realisable transition graph, gFTP assigns values to the network firing states associated with each node in the graph, and finds the synaptic weight matrices by solving a set of linear separation problems. We test gFTP performance by constructing networks with random dynamics, continuous attractor-like dynamics that encode position in 2-dimensional space, and discrete attractor dynamics. We then show how gFTP can be employed as a tool to explore the link between structure, function, and the algorithms instantiated in the network dynamics.

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Brain damage triggers diverse cellular and molecular events, with astrocytes playing a crucial role in activating local neuroprotective and reparative signaling within damaged neuronal circuits. Here, we investigated reactive astrocytes using a multidimensional approach to categorize their responses into different subtypes based on morphology. This approach utilized the StarTrack lineage tracer, single-cell imaging reconstruction and multivariate data analysis. Our findings identified three profiles of reactive astrocyte responses, categorized by their effects on cell size- and shape- related morphological parameters: "moderate", "strong," and "very strong". We also examined the heterogeneity of astrocyte reactivity, focusing on spatial and clonal distribution. Our research revealed a notable enrichment of protoplasmic and fibrous astrocytes within the "strong" and "very strong" response subtypes. Overall, our study contributes to a better understanding of astrocyte heterogeneity in response to an injury. By characterizing the diverse reactive responses among astrocyte subpopulations, we provide insights that could guide future research aimed at identifying novel therapeutic targets to mitigate brain damage and promote neural repair.

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Objective: After deep brain stimulation (DBS), patients with Parkinson's disease (PD) typically still present significant gait and postural stability problems, and thus additional interventions are needed. In this way, our purpose was evaluate the comparative effectiveness of treadmill training, with and without body weight support, on balance outcomes among patients with PD after DBS. Methods: Eleven patients with PD that were using bilateral subthalamic nucleus DBS were evaluated using Time Up and Go test (TUG); Berg Balance Scale (BBS) and Static Posturography. In phase 1, all subjects participated in 8-weeks of treadmill training in conjunction with conventional physiotherapy. After six weeks (wash-out), each patient then participated in a subsequent 8-weeks of treadmill training with partial body weight support. Results: After the phase 1, there were improvements on the cognitive TUG performance (Before: 15.7 ± 1,8 sec; After: 13.7 ± 3.1 sec; p < 0.01) and an increase of anteroposterior and medio-lateral body oscillation with eyes closed. After the phase 2, there were improvements in conventional (Before: 12.3 ± 2.0 sec; After: 10.7 ± 1.7 sec; p < 0.01) and cognitive (Before: 14.6 ± 3.5 sec; After: 12.5 ± 1.6 sec; p < 0.05) TUG performances. There were no significant changes in the Berg Balance Scale following either training protocol. Conclusion: Both trainings improved static and dynamic balance and had similar results; however, supported treadmill training seemed to be a potentially superior option, as patients tended to feel safer. Level of Evidence II, therapeutic studies - investigation of treatment outcomes.

Objetivo: Mesmo após a estimulação cerebral profunda (ECP), os pacientes com doença de Parkinson (DP) muitas vezes ainda apresentam problemas significativos de marcha e estabilidade postural, e, portanto, intervenções adicionais são necessárias. Avaliar a eficácia comparativa do treinamento em esteira, com e sem suporte de peso corporal, nos resultados de equilíbrio de pacientes com DP após ECP. Métodos: Onze pacientes com DP em uso de ECP bilateral do núcleo subtalâmico foram avaliados pelos testes Time Up and Go (TUG), escala de equilíbrio de Berg (EEB) e posturografia estática. Na fase 1, todos participaram de oito semanas de treinamento em esteira em conjunto com fisioterapia convencional. Após seis semanas (wash-out), cada paciente participou de oito semanas subsequentes de treinamento em esteira com suporte parcial de peso corporal. Resultados: Depois da fase 1, houve melhora no desempenho cognitivo do TUG (antes: 15,7 ± 1,8 s; depois: 13,7 ± 3,1 s; p < 0,01) e aumento da oscilação anteroposterior e médio-lateral do corpo com os olhos fechados. Após a fase 2, os resultados do TUG convencional (antes: 12,3 ± 2,0 seg; depois: 10,7 ± 1,7 seg; p < 0,01) e cognitivo (antes: 14,6 ± 3,5 s; depois: 12,5 ± 1,6 s; p < 0,05) demonstraram melhora. Os protocolos de treinamento não causaram mudanças significativas na EEB.. Conclusão: Ambos os treinos melhoraram o equilíbrio estático e dinâmico e tiveram resultados semelhantes; no entanto, o treinamento em esteira com suporte é uma opção potencialmente superior, uma vez que os pacientes tendiam a se sentir mais seguros. Nível de Evidência II, estudos terapêuticos - investigação de resultados de tratamento.

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BACKGROUND: The complexities of unilateral dystonia have led to exploring simultaneous (dual) globus pallidus internus (GPi) and motor ventral thalamus (Vim/Vop) deep brain stimulation (DBS), yet detailed assessments are lacking. OBJECTIVES: To assess the efficacy of GPi, Vim/Vop, and dual DBS in unilateral dystonia. METHODS: Three patients with unilateral dystonia (two idiopathic, one acquired), implanted with two DBS electrodes targeting ipsilateral Vim/Vop and GPi, were included. Three stimulation modalities were assessed. First, one electrode was activated, then the other, and finally, both electrodes were activated simultaneously. RESULTS: DBS yielded substantial symptomatic reductions in all three evaluated stimulation modalities. Patients exhibited varying responses regarding quality-of-life and depressive symptoms. Treatment satisfaction didn't align with clinical improvements, potentially affected by unrealistic expectations. CONCLUSIONS: This study contributes critical insights into GPi, Vim/Vop and simultaneous stimulation for unilateral dystonia. The safety of the procedure underscores the promise of this approach.

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Background: Intracranial teratomas represent a rare subset of neoplasms characterized by tissues derived from multiple germ layers within the cranial cavity. These tumors, originating from primordial germ cells, exhibit diverse clinical presentations and histopathological features. While predominantly located along the midline axis, including the suprasellar cistern and pineal region, they can also manifest in less common areas such as ventricles and hypothalamic regions. Histopathologically, they are classified as mature, immature, or malignant based on the degree of tissue differentiation. Case Description: Male patient with prenatal care for congenital hydrocephalus born at 38 weeks gestation with a bulging fontanelle. Postnatal imaging revealed an intraventricular lesion, later diagnosed through magnetic resonance imaging as a mature teratoma invading the lateral ventricle and extending to the hypothalamus. Surgical resection achieved total macroscopic removal followed by successful postoperative ventriculoperitoneal shunting due to evolving hydrocephalus. Conclusion: Teratomas are uncommon tumors, and prognosis depends on tumor size and location, especially considering the rarity of mature teratomas. Complete surgical resection is paramount for treatment, leading to a better prognosis and quicker recovery. In cases where complete removal is challenging, adjuvant therapies and cerebrospinal fluid diversion may be required to enhance therapeutic outcomes and ensure successful resection.

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Decompressive craniectomy is used to alleviate intracranial pressure in cases of traumatic brain injury and stroke by removing part of the skull to allow brain expansion. Traditionally, this procedure is followed by a watertight dural suture, although evidence supporting this method is not strong. This meta-analysis examines the feasibility of the open-dura (OD) approach versus the traditional closed-dura (CD) technique with watertight suturing. A systematic review and comparative meta-analysis were conducted on OD and CD dural closure techniques. Medline, Embase, and Cochrane were searched for relevant trials. The primary end point was the rate of complications, with specific analyses for infection and cerebrospinal fluid (CSF) leaks. Mortality, poor neurological outcomes, and operation duration were also assessed. Odds ratios with 95% confidence intervals (CIs) were calculated using a random-effects model. Following a comprehensive search, 930 studies were screened, from which four studies and a total of 368 patients were ultimately selected. The primary outcome analysis showed a reduced likelihood of complications in the OD group when compared with the CD group (368 patients, odds ratio 0.54 [95% CI 0.32-0.90]; I2 = 17%; p < 0.05). Specific analysis of infections and CSF leaks did not show statistically significant results, as well as the evaluation of the mortality rates and poor neurological outcome differences between groups. Assessment of operation duration, however, demonstrated a significant difference between techniques, with a mean reduction of 52.50 min favoring the OD approach (mean difference - 52.50 [95% CI - 92.13 to - 12.87]; I2 = 96%). This study supports the viability of decompressive craniectomy without the conventional time-spending watertight duraplasty closure, exhibiting no differences in the rate of infections or CSF leaks. Furthermore, this approach has been associated with improved rates of complications and faster surgery, which are important aspects of this technique, particularly in its potential to reduce both costs and procedure length.

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Stroke is the second most common cause of death and one of the most common causes of disability worldwide. The intestine is home to several microorganisms that fulfill essential functions for the natural and physiological functioning of the human body. There is an interaction between the central nervous system (CNS) and the gastrointestinal system that enables bidirectional communication between them, the so-called gut-brain axis. Based on the gut-brain axis, there is evidence of a link between the gut microbiota and the regulation of microglial functions through glial activation. This interaction is partly due to the immunological properties of the microbiota and its connection with the CNS, such that metabolites produced by the microbiota can cross the gut barrier, enter the bloodstream and reach the CNS and significantly affect microglia, astrocytes and other cells of the immune system. Studies addressing the effects of short-chain fatty acids (SCFAs) on glial function and the BBB in ischemic stroke are still scarce. Therefore, this review aims to stimulate the investigation of these associations, as well as to generate new studies on this topic that can clarify the role of SCFAs after stroke in a more robust manner.

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Obesity is a significant health concern that is correlated with various adverse health outcomes. Diet-induced obesity (DIO) is associated with impaired cognitive function. Pharmacological treatments for obesity are limited and may have serious adverse effects. Zingiber officinale (ZO) has anti-inflammatory and antioxidant effects, in addition to metabolic effects. This study aimed to assess the effects of Zingiber officinale supplementation on cognitive function, anxiety levels, neurotrophin levels, and the inflammatory and oxidative status in the cortex following DIO in mice. Two-month-old male Swiss mice were fed DIO or standard chow for 4 months and subsequently subdivided into the following groups (n = 10 mice/group): (i) control - vehicle (CNT + vehicle); (ii) CNT supplemented with ZO (CNT + ZO); (iii) obese mice (DIO + vehicle); and (iv) obese mice supplemented with ZO (DIO + ZO) (n = 10). Zingiber officinale extract (400 mg/kg/day) was administered for 35 days via oral gavage. The DIO + vehicle group exhibited impaired recognition memory. The CNT + ZO group presented a greater number of crossings in the open field. No difference between the groups was observed in the plus maze test. DIO + vehicle increased the DCFH and carbonylation levels in the cortex. The DIO + vehicle group presented a reduction in catalase activity. The expression of inflammatory or neurotrophin markers in the cerebral cortex was not different. In conclusion, our findings indicate that supplementation with ZO reverses the cognitive impairment in DIO mice and enhances the antioxidant status of the cerebral cortex.