Congenital hydrocephalus (CH) is an extreme cerebrospinal fluid (CSF) condition that affects brain development. Current medical treatments, such as ventriculoperitoneal shunting and endoscopic third ventriculostomy, are invasive and susceptible to complications. The subventricular zone (SVZ) is involved in CH, but investigations are hindered by conventional models. Here, we introduce SVZonChip, a dynamic 3D microfluidic device simulating SVZ physiology and CSF dynamics, presenting a proof-of-concept system that could be applied for studying CH. This bioengineered device provides a translational bridge between disease modeling and therapeutic discovery, opening up avenues for non-invasive treatments.

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The gut microbiota and dysbiosis have been implicated in various metabolic diseases and gastrointestinal disorders. Recently, there has been growing evidence suggesting the influence of gut microbiota on neurological disorders, including autism. Although the number of children diagnosed with autism is increasing, the exact cause of the disease remains unknown. Numerous factors, such as genetics, environment, and diet, appear to contribute to its onset. Nevertheless, a degree of general consensus exists regarding the notion that the disease’s progression likely demands the participation of multiple factors. Among the potential causes, the role of the microbiota is particularly intriguing. The gut and brain have extensive connections, with a significant number of neuronal cells in the gut, and autism is often associated with gastrointestinal issues. In this review, the most recent information available on autism and microbiota has been analyzed. Findings of this study indicate that: (1) the microbiota is clearly altered in individuals with autism spectrum disorder (ASD); (2) microbiota transplantation appears to be effective in reducing the severity of autism symptoms; (3) while the microbiota is not solely responsible for the onset of autism, it likely plays a significant role. Considering all the available information, it is suggested that modifying the gut microbiota may have a positive impact on individuals with autism. This opens up possibilities for the use of pre- or probiotics in the treatment of children with ASD, as well as the potential use of fecal microbiota transfer.

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Several bare metals, self-expanding stents have been approved by the Food and Drug Administration (FDA) to treat carotid stenosis, but no covered stents have been particularly examined or approved for carotid or cerebrovascular applications. Nonetheless, there are a number of potentially useful applications for covered stents in the brachiocephalic, carotid, and even intracranial arteries. As with currently accepted applications for bare metal carotid stents, the use of covered stents in carotid arteries has been reserved for patients who are at high risk for complications with open surgical management of their specific problem. The present case report emphasizes the safety and efficacy of covered stent in complex carotid artery reconstruction entailing stenosis and aneurysmal dilatation and through light on its impact on minimizing the risk of ischemic complications associated with endovascular or surgical carotid sacrifice.

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Over the past decade, knowledge of the pathophysiology and immunology of multiple sclerosis (MS) and depression, and the complex links to vitamin D (VitD) balance, has increased rapidly. Both diseases are characterized by an imbalance of proinflammatory and antiinflammatory cytokines, increased serum neurofilament light chains (sNfLs), disruption of the blood-brain barrier (BBB), abolition of the physiological function of the various types of microglia (MG), decreased calcidiol-serum levels, and disorders of the gut microbiome in combination with hyperactivity of the hypothalamic-pituitary-adrenal (HPA)-axis/microbiome-gut-brain-axis characterized. In depression, stress initiates cellular and molecular changes in the brain via increased cortisol release in the HPA-axis. Microglial activation and neuronal damage as well as dysregulation of neuroplastic and neurotrophic factors complete the spectrum of pathological damage. It is shown that gut dysbiosis leads to increased gut permeability, which favors endotoxemia and ultimately paves the way to systemic inflammation. A VitD supplementation could restore the balance of microorganisms in the intestine and reduce the inflammatory processes at various levels. VitD promotes regulatory T cell (Treg) proliferation, inhibits the expression of T helper 1 (Th1) cells and Th17 immune cells, and inhibits proinflammatory interleukin-17 (IL-17). 1,25-dihydroxyvitamin D₃ [1,25(OH)₂D₃] reduces also the secretion of interferon-γ (IFN-γ) and tumor necrosis factor-α (TNF-α). Increased calcitriol levels lead to a reduction in MG activation, oxidative stress, and lower BBB permeability. An early, permanent, daily sufficient VitD supplementation as an add-on therapy under control of the serum 25-hydroxyvitamin D [s25(OH)D] levels is an essential therapeutic tool to slow down the disability caused by MS and thereby primarily prevent or reduce the stress and subsequently the manifestation of depression. Through the future continuous measurement of the biomarkers serum neurofilament ligth chains and glial fibrillary acidic proteins as well as the s25(OH)D level in MS and comorbidity depression, future therapy successes or failures can be avoided.

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Brain development, a complex process, consisting of several phases, starting as early as two weeks after conception, and continuing through childhood till early adolescence, is crucial for the development of properly functioning body systems, behavioral traits, and neurocognitive abilities. Infancy and childhood are recognized as important periods for initial brain formation, however in later stages of life, such as childhood and adulthood, experiences, together with environmental exposures, can still influence brain physiology. The developing brain is particularly susceptible to epigenetic changes with many factors being proposed as modifiers by directly impacting DNA methylation as well as histone and chromatin modifications within genes implicated in development. These factors include: maternal stress and diet, exposure to pollutants, sleep quality, as well as dietary habits. Evidence indicates exposures to environmental threats can lead to inappropriate neurological, metabolic, and endocrine functioning often mediated by epigenetic mechanisms with symptoms manifesting themselves as early as childhood or in later stages of life. Therefore, the main aim of this review is to evaluate the current studies focused on negative environmental exposures and their consequences on the developing brain directed by epigenetic mechanisms.

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Life is the highest form of adaptation to the environment which is based on energy metabolism. To maintain life, the neuromuscular system must constantly interact with the environment. The striatal muscles are the main energy consumer and their access to energy fuel is mainly limited by the brain’s needs. In the state of wakefulness, the brain must continuously process streams of sensory signals and respond to them with motor actions. At the same time, the brain to be efficient must memorize the sensory-movement relationships. Brain memory networking requires additional energy allocation, and due to limited systemic energy resources, the processes of memorization are completed during the sleep phase when the inactive muscular system allows allocating the energy fuel to the brain functions such as memory trace formation and the removal of the activity-dependent waste products. Both physiological processes can be completed during sleep only, and consequently, chronic sleep disorder leads to pathological changes in brain functioning and escalation of neurodegenerative processes. Consequently, sleep disorders become the main cause of dementia which is the prodrome of Alzheimer’s disease.

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As the average lifespan has increased, memory disorders have become a more pressing public health concern. However, dementia in the elderly population is often neglected in light of other health priorities. Therefore, expanding the knowledge surrounding the pathology of dementia will allow more informed decision-making regarding treatment within elderly and older adult populations. An important emerging avenue in dementia research is understanding the vascular contributors to dementia. This review summarizes potential causes of vascular cognitive impairment like stroke, microinfarction, hypertension, atherosclerosis, blood-brain barrier dysfunction, and cerebral amyloid angiopathy. Also, this review address treatments that target these vascular impairments that also show promising results in reducing patient’s risk for and experience of dementia.

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The two mainstays of therapy for refractory epilepsy are medication and surgery. Child behavioral and cognitive aspects of epilepsy can be improved by using a specialized dietary regimen such as the ketogenic diet (KD). The purpose of this review is to expand our understanding of KD as a nutritional therapy for children with refractory epilepsy and to provide insight into the physiological aspects of its efficacy as an alternative to anti-seizure medication. Either directly or indirectly, ketones, glucose restriction, and polyunsaturated fatty acids regulate epileptic seizures. For KD to be effective, all three of these components must be present, even though the exact mechanism is unknown. Increasing gamma-aminobutyric acid, mitochondrial biogenesis, and oxidative phosphorylation levels can also serve as a means of promoting stable synaptic function while also decreasing neural activity and excitability. Most side effects of KD are caused by mild metabolic abnormalities such as acidosis, hyperuricemia, hypercholesterolemia, hypocalcemia, and hypomagnesemia. Since medium-chain triglycerides (MCTs) produce more ketones per calorie than long-chain triglycerides, individuals who consume MCTs can consume more carbohydrates and protein. This review demonstrated that KD therapy led to positive outcomes for patients with refractory epilepsy. Further study is needed to evaluate whether less restrictive and easier-to-follow diets, such as the modified Atkins diet and MCT diets, have a similar effect on seizure treatment as the standard KD.

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All living organisms exhibit circadian rhythms. Humans show circadian rhythm of the different physiological functions such as sleep-wake cycle, core body temperature, feeding behavior, metabolic activity, heart rate variability, hormone secretion, and others. The hypothalamic suprachiasmatic nucleus (SCN) acts as a primary circadian pacemaker. Peripheral tissues have an endogenous circadian clock; however, SCN synchronizes the circadian activity of the peripheral clocks. The retinohypothalamic tract (RHT) from retinal ganglionic cells carries the photic signal into the SCN that regulates the rhythmic expression of the core clock genes through the feedback loop. At the output level, the SCN connects with the pineal gland and the peripheral tissues with the help of neuroendocrine mediators. Disruption of circadian clock functions is detrimental to health. Shift work, night work, chronic or acute jet lag, and light-at-night have adverse effects on circadian functions. Misalignment of circadian rhythm alters the expression of core clock genes, leading to deregulation of cellular activity and metabolic functions. Circadian rhythm dysfunction causes many pathologic conditions, including sleep disorders, cardiovascular problems, metabolic dysfunction, infertility, poor physical performance, as well as cancer. The present work has reviewed the relationship between circadian clock dysfunction and impaired physiological activities.

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Neuregulins (NRGs) and their cognate ErbB receptors (ErbB2–ErbB4) constitute a vast group of proteins encoded by six different genes (NRG1–6) and many isoforms with critical roles in the development and functioning of the nervous system. NRGs are known to regulate important processes in the nervous system like neural development, neuronal differentiation, neurite outgrowth, and specification. These factors are involved in the regulation of neurotransmission pathways and the modulation of several forms of synaptic plasticity. Due to NRGs’ role in synaptic plasticity, defects in their normal functioning are translated into altered signaling networks, which have been linked to susceptibility to developing psychiatric disorders like schizophrenia (SZ), autism, depression, and bipolar disorders. Additionally, deviation of the NRG normal functioning is involved in neurological diseases like Alzheimer’s and Parkinson’s disease. Contrastingly, NRG/ErbB signaling is also involved in the recovery after traumatic brain injuries (e.g., ischemic stroke). The NRG/ErbB signaling complex is highly unusual because the ligands (mainly NRG1–NRG3, with their multiple isoforms) and receptors (ErbB2–ErbB4) can orchestrate vast signaling complexes, with a wide reach within the processes that govern the development and appropriate function of the nervous system. This may explain why NRGs and ErbB receptor genes have been linked to complex brain disorders, like SZ. This review, are discussed important aspects of NRG and their relevance for nervous system functioning, including 1) subcellular localization, 2) signaling pathways involved in neuronal functions, 3) effect on neurite development and synapse formation, 4) modulation of some mechanisms of synaptic plasticity [long-term potentiation (LTP), depotentiation, long-term depression (LTD)] and 5) roles of NRGs in some neurological diseases. This review intends to present a summary of the main findings about this family of proteins, which might position them as one of the master regulators of brain functioning.

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This brief statement describes some recent achievements of neuropathological research, with the focus on Alzheimer’s and other age-related diseases, neurodegenerative disorders (tauopathies, synucleinopathies), multimorbidity of the aged brain, multiple sclerosis (MS), and other neuroinflammatory disorders, including central nervous system involvement by coronavirus disease 2019 (COVID-19), as well as new developments in neurovascular diseases, neurooncology, and myopathies. Although neuropathology, using modern technologies, such as cryo-electron microscopy, proteomic and experimental methods, has helped to increase diagnostic accuracy and provided insight into the pathogenesis of many neurological disorders, future studies in co-operation with clinical and other neurosciences should overcome the challenges of disease-influencing therapeutic approaches.

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Ischemic stroke is a highly prevalent condition that frequently results in life-long disability and death. Considerable efforts have been made to establish treatments that prevent secondary ischemic damage and promote stroke recovery. Until now, the recanalization of occluded blood vessels via thrombolysis and thrombectomy, although highly potent, remains the only treatment in humans that enhances stroke outcome. Small extracellular vesicles are non-replicating, nano-sized (70–150 nm) lipid bilayer-enclosed vesicles, which have shown remarkable biological activities in various physiological and pathophysiological contexts. When administered post-stroke, mesenchymal stromal cell-derived extracellular vesicles (MSC-EVs) induce neuroprotection, promote brain remodeling and plasticity, and enhance neurological recovery in rodents and non-human primates via mechanisms that involve immunomodulation and anti-inflammation. In this review, experimental studies on the therapeutic actions of MSC-EVs in animal stroke models are summarized and perspectives for clinical translation are outlined.

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The therapy of many neurological disorders has advanced markedly during recent decades. Not so for neurodegenerative disorders. Early detection, deep individual genotyping and phenotyping, and personalized therapies have been suggested as the way forward. However, we still do not know enough about the aetiology and molecular basics of these diseases. In fact, the term neurodegenerative disorder may be a misleading categorization that constitutes a major cognitive barrier against better characterization and understanding of these disorders. Therefore, we need to go back to the basics and employ novel, open-minded observational study protocols that combine very extensive and robust clinical, molecular and epidemiological data collection methods. Moreover, we need to reconsider our basic orientation towards these diseases to increase our chances of finding out what we are actually trying to care for and cure.

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Stroke is a leading cause of morbidity and mortality. The advent of mechanical thrombectomy has largely improved patient outcomes. This article reviews the features and outcomes associated with aspiration, stent retrievers, and combination catheters used in current practice. There is also a discussion on clinical considerations based on anatomical features and clot composition. The reperfusion grading scale and outcome metrics commonly used following thrombectomy when a patient is still in the hospital are reviewed. Lastly, there are proposed discharge and outpatient follow-up goals in caring for patients hospitalized for a stroke.

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Exposure to stressful conditions plays a critical role in brain processes, including neural plasticity, synaptic transmission, and cognitive functions. Since memory-related brain regions, the hippocampus (Hip), the amygdala, and the prefrontal cortex, express high glucocorticoid receptors (GRs), these areas are the potential targets of stress hormones. Stress affects memory encoding, consolidation, and retrieval, which may depend on many factors such as the type, duration, the intensity of the stressor or the brain region. Here, this review mainly focused on the mechanisms involved in stress-induced memory impairment. Acute/chronic stress induces structural and functional changes in neurons and glial cells. Dendritic arborization, reduction of dendritic spine density, and alteration in glutamatergic-mediated synaptic transmission via N-methyl-D-aspartate (NMDA) and α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA) receptors are mechanisms that stress affect long-term memory formation. Exposure to acute or chronic stress could interplay with multiple neurotransmitter signaling, modulating the neuronal circuits involved in memory impairment or state-dependent learning. Stress hormones also modulate the expression of microRNAs in the specific brain regions responsible for stress-induced behaviors. Because of expressing GRs in astrocytes and microglial cells, stress could affect the morphology, structure, and functions of these glial cells in memory-related brain regions. Astrocytes play a crucial role in stress-induced aversive or fear memory formation. Over-activation of the microglial cells enhances the release of inflammatory cytokines, which results in neuronal injury. Stress has a prominent role in cognitive decline to induces memory problems, particularly in older adults. Due to the issue’s importance, here the provided overview attempted to address the question of how stress alters neuronal epigenetic regulators, synaptic transmissions, and glial activity in the brain.

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Astrocytomas include a wide range of tumors with unique mutations and varying grades of malignancy. These tumors all originate from the astrocyte, a star-shaped glial cell that plays a major role in supporting functions of the central nervous system (CNS), including blood-brain barrier (BBB) development and maintenance, water and ion regulation, influencing neuronal synaptogenesis, and stimulating the immunological response. In terms of epidemiology, glioblastoma (GB), the most common and malignant astrocytoma, generally occur with higher rates in Australia, Western Europe, and Canada, with the lowest rates in Southeast Asia. Additionally, significantly higher rates of GB are observed in males and non-Hispanic whites. It has been suggested that higher levels of testosterone observed in biological males may account for the increased rates of GB. Hereditary syndromes such as Cowden, Lynch, Turcot, Li-Fraumeni, and neurofibromatosis type 1 have been linked to increased rates of astrocytoma development. While there are a number of specific gene mutations that may influence malignancy or be targeted in astrocytoma treatment, O⁶-methylguanine-DNA methyltransferase (MGMT) gene function is an important predictor of astrocytoma response to chemotherapeutic agent temozolomide (TMZ). TMZ for primary and bevacizumab in the setting of recurrent tumor formation are two of the main chemotherapeutic agents currently approved in the treatment of astrocytomas. While stereotactic radiosurgery (SRS) has debatable implications for increased survival in comparison to whole-brain radiotherapy (WBRT), SRS demonstrates increased precision with reduced radiation toxicity. When considering surgical resection of astrocytoma, the extent of resection (EoR) is taken into consideration. Subtotal resection (STR) spares the margins of the T1 enhanced magnetic resonance imaging (MRI) region, gross total resection (GTR) includes the margins, and supramaximal resection (SMR) extends beyond the margin of the T1 and into the T2 region. Surgical resection, radiation, and chemotherapy are integral components of astrocytoma treatment.

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