Identification of a Subpopulation of Astrocyte Progenitor Cells in the Neonatal Subventricular Zone: Evidence that Migration is Regulated by Glutamate Signaling.

In mice engineered to express enhanced green fluorescent protein (eGFP) under the control of the entire glutamate transporter 1 (GLT1) gene, eGFP is found in all 'adult' cortical astrocytes. However, when 8.3 kilobases of the human GLT1/EAAT2 promoter is used to control expression of tdTomato (tdT), tdT is only found in a subpopulation of these eGFP-expressing astrocytes.

Chemogenetic Breakdown of the Dentate Gate Causes Seizures and Spatial Memory Deficits.

The dentate gyrus has often been posited to act as a gate that dampens highly active afferent input into the hippocampus. Effective gating is thought to prevent seizure initiation and propagation in the hippocampus and support learning and memory processes. Pathological changes to DG circuitry that occur in temporal lobe epilepsy (TLE) can increase DG excitability and impair its gating ability which can contribute to seizures and cognitive deficits.

On-Demand Seizures Facilitate Rapid Screening of Therapeutics for Epilepsy.

Animal models of epilepsy are critical in drug development and therapeutic testing, but dominant methods for pharmaceutical evaluation face a tradeoff between higher throughput and etiological relevance. For example, in temporal lobe epilepsy, a type of epilepsy where seizures originate from limbic structures like the hippocampus, the main screening models are either based on acutely induced seizures in wild type, naïve animals or spontaneous seizures in chronically epileptic animals. Both types have their disadvantages - the acute convulsant or kindling induced seizures do not account for the myriad neuropathological changes in the diseased, epileptic brains, and spontaneous behavioral seizures are sparse in the chronically epileptic models, making it time-intensive to sufficiently power experiments.

Prolonged Hyperactivity Elicits Massive and Persistent Chloride Ion Redistribution in Subsets of Cultured Hippocampal Dentate Granule Cells.

Chloride ions play a critical role in neuronal inhibition through the activity of chloride-permeable GABA receptor channels. Ion transporters, chloride channels, and immobile ion species tightly regulate intracellular chloride concentrations. Several studies related to epilepsy suggest that chloride extrusion function may decrease in an activity-dependent manner.

Transparent MXene Microelectrode Arrays for Multimodal Mapping of Neural Dynamics.

Transparent microelectrode arrays have proven useful in neural sensing, offering a clear interface for monitoring brain activity without compromising high spatial and temporal resolution. The current landscape of transparent electrode technology faces challenges in developing durable, highly transparent electrodes while maintaining low interface impedance and prioritizing scalable processing and fabrication methods. To address these limitations, we introduce artifact-resistant transparent MXene microelectrode arrays optimized for high spatiotemporal resolution recording of neural activity.

Impact of atherothrombotic risk stratification in patients with heavily calcified lesions following rotational atherectomy.

Background: Patients who undergo percutaneous coronary intervention (PCI) with rotational atherectomy (RA) are at high risk of adverse clinical outcomes, and there are few clinical risk stratification tools for these patients.

Methods: We conducted a study with 196 patients who underwent PCI with RA out of 7391 patients who underwent PCI using a multicenter, prospective cohort registry. Patients were divided into three groups according to the tertiles of the Thrombolysis in Myocardial Infarction (TIMI) Risk Score for Secondary Prevention (TRS 2°P): 65 patients in the T1 group (TRS 2°P < 3), 66 patients in the T2 group (TRS 2°P = 3), and 65 patients in the T3 group (TRS 2°P > 3).

Optimal medical therapy after percutaneous coronary intervention in very elderly patients with coronary artery disease.

Background: It is still unclear whether optimal medical therapy (OMT) after percutaneous coronary intervention (PCI) has beneficial effects on long-term clinical outcomes in patients aged ≥80 years with coronary artery disease (CAD).

Methods: This study analyzed the time to the first major adverse clinical event including death or nonfatal myocardial infarction (MI), for up to 3 years after PCI using multicenter registry data. Data for 1056 patients aged > 80 years successfully treated with PCI were included in the analysis.

Inhibition of advanced glycation end product formation and serum protein infiltration in bioprosthetic heart valve leaflets: Investigations of anti-glycation agents and anticalcification interactions with ethanol pretreatment.

Bioprosthetic heart valves (BHV) fabricated from heterograft tissue, such as glutaraldehyde pretreated bovine pericardium (BP), are the most frequently used heart valve replacements. BHV durability is limited by structural valve degeneration (SVD), mechanistically associated with calcification, advanced glycation end products (AGE), and serum protein infiltration. We investigated the hypothesis that anti-AGE agents, Aminoguanidine, Pyridoxamine [PYR], and N-Acetylcysteine could mitigate AGE-serum protein SVD mechanisms in vitro and in vivo, and that these agents could mitigate calcification or demonstrate anti-calcification interactions with BP pretreatment with ethanol.

A Stratified Analysis of the Risk Associated With Low Body Mass Index for Patients After Percutaneous Coronary Intervention.

Aims: The relationship between low body mass index (BMI) and prognostic factors for patients with coronary artery disease, commonly observed in elderly individuals in Japan, is important. Few studies have evaluated the prognosis for patients with low BMI after percutaneous coronary intervention (PCI). Using a multivariable-adjusted model and data from a prospective cohort registry, we analyzed the risk associated with low BMI for patients after PCI.

Multimodal, Multiscale Insights into Hippocampal Seizures Enabled by Transparent, Graphene-Based Microelectrode Arrays.

Hippocampal seizures are a defining feature of mesial temporal lobe epilepsy (MTLE). Area CA1 of the hippocampus is commonly implicated in the generation of seizures, which may occur because of the activity of endogenous cell populations or of inputs from other regions within the hippocampal formation. Simultaneously observing activity at the cellular and network scales remains challenging.

A Propensity Score Matched Analysis of Statin Effects on Major Adverse Cardiac Events after Percutaneous Coronary Intervention in Patients Over 75 Years Old.

Objective In an extremely aging society, it is beneficial to reconsider the value of medical treatment for extremely elderly patients. We therefore focused on the efficacy of statin therapy in extremely elderly patients. This study investigated the efficacy of statins for secondary prevention in patients over 75 years old.

Poly-2-methyl-2-oxazoline-modified bioprosthetic heart valve leaflets have enhanced biocompatibility and resist structural degeneration.

Bioprosthetic heart valves (BHV) fabricated from glutaraldehyde-fixed heterograft tissue, such as bovine pericardium (BP), are widely used for treating heart valve disease, a group of disorders that affects millions. Structural valve degeneration (SVD) of BHV due to both calcification and the accumulation of advanced glycation end products (AGE) with associated serum proteins limits durability. We hypothesized that BP modified with poly-2-methyl-2-oxazoline (POZ) to inhibit protein entry would demonstrate reduced accumulation of AGE and serum proteins, mitigating SVD.

Stratification Analysis of Statin Effect on Major Adverse Cardiac Events After Percutaneous Coronary Intervention in Patients on Hemodialysis.

The statin use in patients on hemodialysis remains controversial, and no beneficial effects of statin on the reduction of adverse cardiovascular events have been reported in these patients. This study used stratification analysis to examine the clinical factors in patients on hemodialysis who could benefit from statin for secondary prevention. This prospective multicenter study included 234 consecutive patients on hemodialysis with coronary artery disease who underwent successful reperfusion therapy with percutaneous coronary intervention.

Functional NMDA receptors are expressed by human pulmonary artery smooth muscle cells.

N-methyl-D-aspartate (NMDA) receptors are widely expressed in the central nervous system. However, their presence and function at extraneuronal sites is less well characterized. In the present study, we examined the expression of NMDA receptor subunit mRNA and protein in human pulmonary artery (HPA) by quantitative polymerase chain reaction (PCR), immunohistochemistry and immunoblotting.

Multimodal in vivo recording using transparent graphene microelectrodes illuminates spatiotemporal seizure dynamics at the microscale.

Neurological disorders such as epilepsy arise from disrupted brain networks. Our capacity to treat these disorders is limited by our inability to map these networks at sufficient temporal and spatial scales to target interventions. Current best techniques either sample broad areas at low temporal resolution (e.

Model studies of advanced glycation end product modification of heterograft biomaterials: The effects of in vitro glucose, glyoxal, and serum albumin on collagen structure and mechanical properties.

Glutaraldehyde cross-linked heterograft tissues, bovine pericardium (BP) or porcine aortic valves, are the leaflet materials in bioprosthetic heart valves (BHV) used in cardiac surgery for heart valve disease. BHV fail due to structural valve degeneration (SVD), often with calcification. Advanced glycation end products (AGE) are post-translational, non-enzymatic reaction products from sugars reducing proteins.

Aged heterozygous Cdkl5 mutant mice exhibit spontaneous epileptic spasms.

CDKL5 deficiency disorder (CDD) is a devastating neurodevelopmental disorder characterized by early-onset epilepsy, severe intellectual disability, cortical visual impairment and motor disabilities. Epilepsy is a central feature of CDD, with most patients having intractable seizures, but seizure frequency and severity can vary. Clinical reports demonstrate a diversity in seizure semiology and electrographic features, with no pattern diagnostic of CDD.

Circuit-based interventions in the dentate gyrus rescue epilepsy-associated cognitive dysfunction.

Temporal lobe epilepsy is associated with significant structural pathology in the hippocampus. In the dentate gyrus, the summative effect of these pathologies is massive hyperexcitability in the granule cells, generating both increased seizure susceptibility and cognitive deficits. To date, therapeutic approaches have failed to improve the cognitive symptoms in fully developed, chronic epilepsy.

Altered NMDAR signaling underlies autistic-like features in mouse models of CDKL5 deficiency disorder.

CDKL5 deficiency disorder (CDD) is characterized by epilepsy, intellectual disability, and autistic features, and CDKL5-deficient mice exhibit a constellation of behavioral phenotypes reminiscent of the human disorder. We previously found that CDKL5 dysfunction in forebrain glutamatergic neurons results in deficits in learning and memory. However, the pathogenic origin of the autistic features of CDD remains unknown.

α-Synuclein (αSyn) Preformed Fibrils Induce Endogenous αSyn Aggregation, Compromise Synaptic Activity and Enhance Synapse Loss in Cultured Excitatory Hippocampal Neurons.

Synucleinopathies are characterized by the accumulation of insoluble α-synuclein (αSyn). To test whether αSyn aggregates modulate synaptic activity, we used a recently developed model in primary neurons for inducing αSyn pathology. We demonstrated that preformed fibrils (PFFs) generated with recombinant human αSyn compromised synaptic activity in a time- and dose-dependent manner and that the magnitude of these deficits correlated with the formation of αSyn pathology in cultured excitatory hippocampal neurons from both sexes of mice.

Possible Contribution of Wnt-Responsive Chondroprogenitors to the Postnatal Murine Growth Plate.

Active cell proliferation and turnover in the growth plate is essential for embryonic and postnatal bone growth. We performed a lineage tracing of Wnt/β-catenin signaling responsive cells (Wnt-responsive cells) using Axin2 ;Rosa26ZsGreen mice and found a novel cell population that resides in the outermost layer of the growth plate facing the Ranvier's groove (RG; the perichondrium adjacent to growth plate). These Wnt-responsive cells rapidly expanded and contributed to formation of the outer growth plate from the neonatal to the growing stage but stopped expanding at the young adult stage when bone longitudinal growth ceases.

Heparan sulfate antagonism alters bone morphogenetic protein signaling and receptor dynamics, suggesting a mechanism in hereditary multiple exostoses.

Hereditary multiple exostoses (HME) is a pediatric disorder caused by heparan sulfate (HS) deficiency and is characterized by growth plate-associated osteochondromas. Previously, we found that osteochondroma formation in mouse models is preceded by ectopic bone morphogenetic protein (BMP) signaling in the perichondrium, but the mechanistic relationships between BMP signaling and HS deficiency remain unclear. Therefore, we used an HS antagonist (surfen) to investigate the effects of this HS interference on BMP signaling, ligand availability, cell-surface BMP receptor (BMPR) dynamics, and BMPR interactions in Ad-293 and C3H/10T1/2 cells.

Loss of CDKL5 in Glutamatergic Neurons Disrupts Hippocampal Microcircuitry and Leads to Memory Impairment in Mice.

Cyclin-dependent kinase-like 5 (CDKL5) deficiency is a neurodevelopmental disorder characterized by epileptic seizures, severe intellectual disability, and autistic features. Mice lacking CDKL5 display multiple behavioral abnormalities reminiscent of the disorder, but the cellular origins of these phenotypes remain unclear. Here, we find that ablating CDKL5 expression specifically from forebrain glutamatergic neurons impairs hippocampal-dependent memory in male conditional knock-out mice.