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Objective: The risk of hydrocephalus following hemispherectomy for drug resistant epilepsy (DRE) remains high. Patients with pre-existing hydrocephalus pose a postoperative challenge, as maintaining existing shunt patency is necessary but lacks a clearly defined strategy. This study examines the incidence and predictors of shunt failure in pediatric hemispherectomy patients with pre-existing ventricular shunts. Methods: We performed a retrospective chart review at our center to identify pediatric patients diagnosed with DRE who were treated with ventricular shunt prior to their first hemispherectomy surgery. Demographic and perioperative data were obtained including shunt history, hydrocephalus etiology, epilepsy duration, surgical technique, and postoperative outcomes. Univariate analysis was performed using Fisher's exact test and Pearson correlation, with Bonferroni correction to a = 0.00625 and a = 0.01, respectively. Results: Five of nineteen (26.3%) patients identified with ventriculoperitoneal shunting prior to hemispherectomy experienced postoperative shunt malfunction. All 5 of these patients underwent at least 1 shunt revision prior to hemispherectomy, with a significant association between pre- and post-hemispherectomy shunt revisions. There was no significant association between post-hemispherectomy shunt failure and valve type, intraoperative shunt alteration, postoperative external ventricular drain placement, hemispherectomy revision, lateralization of shunt relative to resection, postoperative complications, or postoperative aseptic meningitis. There was no significant correlation between number of post-hemispherectomy shunt revisions and age at shunt placement, age at hemispherectomy, epilepsy duration, or shunt duration prior to hemispherectomy. Conclusions: Earlier shunt revision surgery may portend a subsequent need for shunt revision following hemispherectomy. These findings may guide neurosurgeons in counseling patients with pre-existing ventricular shunts prior to hemispherectomy surgery. [ABSTRACT FROM AUTHOR]

To date, treatment of Central Nervous System (CNS) pathology has largely focused on neuronal structure and function. Yet, revived attention towards fluid circulation within the CNS has exposed the need to further explore the role of glial cells in maintaining homeostasis within neural networks. In the past decade, discovery of the neural glymphatic network has revolutionized traditional understanding of fluid dynamics within the CNS. Advancements in neuroimaging have revealed alternative pathways of cerebrospinal fluid (CSF) generation and efflux. Here, we discuss emerging perspectives on the role of astrocytes in CSF hydrodynamics, with particular focus on the contribution of aquaporin-4 channels to the glymphatic network. Astrocytic structural features and expression patterns are detailed in relation to their function in maintaining integrity of the Blood Brain Barrier (BBB) as part of the neurovascular unit (NVU). This narrative also highlights the potential role of glial dysfunction in pathogenesis of neurodegenerative disease, hydrocephalus, intracranial hemorrhage, ischemic stroke, and traumatic brain injury. The purpose of this literature summary is to provide an update on the changing landscape of scientific theory surrounding production, flow, and absorption of cerebrospinal fluid. The overarching aim of this narrative review is to advance the conception of basic, translational, and clinical research endeavors investigating glia as therapeutic targets for neurological disease. [ABSTRACT FROM AUTHOR]

In living organisms, enzyme catalysis takes place in aqueous media with extraordinary spatiotemporal control and precision. The mechanistic knowledge of enzyme catalysis and related approaches of creating a suitable microenvironment for efficient chemical transformations have been an important source of inspiration for the design of biomimetic artificial catalysts. However, in "nature-like" environments, it has proven difficult for artificial catalysts to promote effective chemical transformations. Besides, control over reaction rate and selectivity are important for smart application purposes. These can be achieved via incorporation of stimuli-responsive features into the structure of smart catalytic systems. Here, we summarize such catalytic systems whose activity can be switched 'on' or 'off' by the application of stimuli in aqueous environments. We describe the switchable catalytic systems capable of performing organic transformations with classification in accordance to the stimulating agent. Switchable catalytic activity in aqueous environments provides new possibilities for the development of smart materials for biomedicine and chemical biology. Moreover, engineering of aqueous catalytic systems can be expected to grow in the coming years with a further broadening of its application to diverse fields. Control over chemical transformations in aqueous environments employing catalytic systems whose activity can be switched on/off is challenging. Here, the authors review the switchable catalytic systems that operate in aqueous environments in response to external stimuli, such as pH, temperature, light, small molecules, electric field, magnetic field and mechanical energy. [ABSTRACT FROM AUTHOR]

Although several histochemical markers for senile plaques (SP) and neurofibrillary tangles (NFTs) have been synthesized since the discovery of plaques in Alzheimer's disease (AD), only a handful of these markers stain both lesions in the human brain. Despite discovery of its ability to stain both SP and NFT over 13 years ago, the styrylbenzene derivative, (E,E)-1-fluoro-2,5-bis-(3-hydroxycarbonyl-4-hydroxy)styrylbenzene (FSB), has only recently gained attention, primarily due to its ability to function as a contrasting agent for MRI imaging of AD pathology in vivo. The structure of the compound is a nuclide with quantized angular momentum, which explains its value as a contrast agent. In the current study, modification of the established staining procedure produced meaningful improvement in the labeling of plaques and tangles in the human brain. We utilized two rodent models of AD to show FSB's value in labeling both Aβ and tau lesions. Furthermore, our current modification allows us to detect SP in rodent brains in 15 min and both SP and NFT in human brains within 20 min. The study presents new evidence regarding potential binding targets for FSB as well as optimization protocols in which various parameters have been manipulated to show how section thickness, use of frozen versus paraffin-embedded sections, and selection of staining media can affect the intensity of the plaque and tangle staining in the brain. To determine the target FSB potentially binds, we performed double immunolabeling of FSB with mOC64 (a conformational antibody that label Aβ1-42). Results indicated that all plaques in the brain colocalized with mOC64, suggesting that FSB has the potential to bind all Aβ containing plaques, making it a very sensitive detector of multiple forms of SP... All antibodies were assessed for the degree of colocalization with FSB in order to better understand potential binding targets. We found more than 90% hyperphosphorylated Tau against AT8, AT180 and S214 colocalized with FSB labeled tangles. On the other hand, more than 90% of the mOC64 containing plaques colocalized with FSB stained plaques. Our results indicate that FSB is a valuable marker that can be used to detect AD pathologies in human and rodent brains with greater fluorescence intensity relative to other conventional fluorescence markers. [ABSTRACT FROM AUTHOR]

Nature produces materials using available molecular building blocks following a bottom-up approach. These materials are formed with great precision and flexibility in a controlled manner. This approach offers the inspiration for manufacturing new artificial materials and devices. Synthetic artificial materials can find many important applications ranging from personalized therapeutics to solutions for environmental problems. Among these materials, responsive synthetic materials are capable of changing their structure and/or properties in response to external stimuli, and hence are termed "smart" materials. Herein, this review focuses on alginate-based smart materials and their stimuli-responsive preparation, fragmentation, and applications in diverse fields from drug delivery and tissue engineering to water purification and environmental remediation. In the first part of this report, we review stimuli-induced preparation of alginate-based materials. Stimuli-triggered decomposition of alginate materials in a controlled fashion is documented in the second part, followed by the application of smart alginate materials in diverse fields. Because of their biocompatibility, easy accessibility, and simple techniques of material formation, alginates can provide solutions for several present and future problems of humankind. However, new research is needed for novel alginate-based materials with new functionalities and well-defined properties for targeted applications. [ABSTRACT FROM AUTHOR]