Overexpression of α-Klotho isoforms promotes distinct Effects on BDNF-Induced Alterations in Dendritic Morphology.

α-Klotho (α-Kl) is a modulator of aging, neuroprotection, and cognition. Transcription of the Klotho gene produces two splice variants-a membrane protein (mKl), which can be cleaved and released into the extracellular milieu, and a truncated secreted form (sKl). Despite mounting evidence supporting a role for α-Kl in brain function, the specific roles of α-Kl isoforms in neuronal development remain elusive. Here, we examined α-Kl protein levels in rat brain and observed region-specific expression in the adult that differs between isoforms. In the developing hippocampus, levels of isoforms decrease after the third postnatal week, marking the end of the critical period for development. We overexpressed α-Kl isoforms in primary cultures of rat cortical neurons and evaluated effects on brain-derived neurotrophic factor (BDNF) signaling. Overexpression of either isoform attenuated BDNF-mediated signaling and reduced intracellular Ca2+ levels, with mKl promoting a greater effect. mKl or sKl overexpression in hippocampal neurons resulted in a partially overlapping reduction in secondary dendrite branching. Moreover, mKl overexpression increased primary dendrite number. BDNF treatment of neurons overexpressing sKl resulted in a dendrite branching phenotype similar to control neurons. In neurons overexpressing mKl, BDNF treatment restored branching of secondary and higher order dendrites close, but not distal, to the soma. Taken together, the data presented support the idea that sKl and mKl play distinct roles in neuronal development, and specifically, in dendrite morphogenesis.

The Accreditation Council for Graduate Medical Education 20-Year Trends in Diversity, Equity, and Inclusion in the United States: How Does Neurological Surgery Compare?

BACKGROUND: Within the current medical workforce, diversity is limited among surgical specialties. However, diversity allows physicians to provide culturally competent care. This paper discusses the trends in racial, ethnic, and gender representation within different surgical subspecialties with an emphasis on neurosurgery over a 20-year time frame. METHODS: A retrospective review of data collected by the Accreditation Council for Graduate Medical Education over the past twenty years, as reported in Journal of the American Medical Association, was conducted. Residents from 5 surgical specialties were evaluated based on gender, race, and ethnic identifications from 2002 to 2022. One-way analysis of variance was performed to compare the levels and retention rates of racial, ethnic, and gender diversity within these specialties. RESULTS: Analysis of resident demographics of the 5 surgical specialties reveals an overall trend of increasing diversity over the study period. Over the past 20 years, neurosurgery had an overall increase in Asian (+5.1%), Hispanic (+3.0%), and female (+11.4%) residents, with a decrease in White residents by 2.1% and Black residents by 1.1%. Among the surgical specialties analyzed, otolaryngology had the greatest overall increase in minority residents. Notably, there has been an overall increase in female residents across all 5 surgical specialties, with the highest in otolaryngology (+20.3%) which was significantly more than neurosurgery (P < 0.001). CONCLUSIONS: This chronological analysis spanning 20 years demonstrates that neurosurgery, like other specialties, has seen a growth in several racial and ethnic categories. Relative differences are notable in neurosurgery, including Black, Asian, Hispanic, and White ethnic categories, with growth in females, but at a significantly lesser pace than seen in otolaryngology and plastic surgery.

Neurovascular considerations in patients with Down syndrome and moyamoya syndrome.

In this article, we describe a rare and complex case of moyamoya syndrome in a 7-year-old boy with Down syndrome and atlantoaxial subluxation. The patient presented with an ischemic stroke in the left hemisphere and cervical cord compression with increased cord edema. Diagnostic digital subtraction angiography revealed unique patterns of vascular involvement, with retrograde flow through the anterior spinal artery, ascending cervical artery, occipital artery, and multiple leptomeningeal arteries compensating for bilateral vertebral artery occlusion. This case underscores the underreported phenomenon of upward retrograde flow through the anterior spinal artery in bilateral vertebral artery occlusion. We address the rare manifestation of posterior circulation involvement in moyamoya syndrome, highlighting the importance of considering atlantoaxial instability as a contributing factor, as the absence of atlantoaxial stability is a risk factor for vertebral artery dissection. This study contributes valuable insights into the intricate relationship of moyamoya syndrome, Down syndrome, and atlantoaxial instability, urging clinicians to consider multifaceted approaches in diagnosis and treatment. It also emphasizes the potential significance of the anterior spinal artery as a compensatory pathway in complex vascular scenarios.

Biopsy of diffuse midline glioma is safe and impacts targeted therapy: a systematic review and meta-analysis.

PURPOSE: To quantify the safety and utility of biopsy of pediatric diffuse midline glioma (DMG). METHODS: This study was conducted in accordance with PRISMA guidelines. PubMed, Embase, Scopus, and Web of Science were queried for relevant articles from inception until June 2023. Two reviewers identified all articles that included diagnostic yield, morbidity, and mortality rates for pediatric DMG patients. Studies that did not present original data or were not in English or peer-reviewed were excluded. Meta-analysis was conducted in R using Freeman-Tukey or logit transformation and DerSimonian-Laird random-effects models. The risk of bias was assessed using the Newcastle-Ottawa Scale. A protocol for this review was not registered. RESULTS: We identified 381 patients from ten studies that met all criteria. DMG biopsy is safe overall (0% mortality, 95% CI: 0-0.6%; 11.0% morbidity, 95% CI: 4.8-18.9%) and has a high diagnostic yield (99.9%, 95% CI: 98.5-100%). The use of stereotactic biopsy is a significant moderator of morbidity (p = 0.0238). Molecular targets can be identified in approximately 53.4% of tumors (95% CI: 37.0-69.0%), although targeted therapies are only delivered in about 33.5% of all cases (95% CI: 24.4-44.1%). Heterogeneity was high for morbidity and identification of targets. The risk of bias was low for all studies. CONCLUSION: We conducted the first meta-analysis of DMG biopsy to show that it is safe, effective, and able to identify relevant molecular targets that impact targeted therapy.

The landscape of current research on pediatric diffuse midline glioma: a quantitative analysis of shifts, leaders, and future avenues.

PURPOSE: Diffuse midline glioma (DMG) has seen a surge of research interest in recent years with the growth in knowledge of new avenues for potential treatments. However, no bibliometric review of the field has been conducted to visualize the current state of the field. Here, we use bibliometric mapping to visualize the knowledge structure, collaborations, and trends in the field. METHODS: A total of 1079 original and review articles from 1996 to 2023 on diffuse midline glioma were extracted from the Web of Science Core Collection on June 3, 2023. These files were analyzed with R and VOSviewer to construct bibliometric visualizations. RESULTS: Research interest in DMG has continued to grow, driven by publications of original research. Molecular characterization of DMG has been a key focus of recent literature, and terms relating to novel small molecules, mutations, immunotherapy, the blood-brain barrier, and liquid biopsy may be areas for future growth in the literature. Collaborating nations have generally been the North American and European nations, but other nations have begun to make their mark in the field. Leading and rising institutions and journals are described. CONCLUSION: Research in DMG may continue to focus on molecular characterization and new therapeutics based on this knowledge. Novel collaborations between rising nations and institutions in the field may aid in accelerating this research.

Trends in Global Research for Treating Intracranial Aneurysms: A Bibliometric Analysis.

OBJECTIVE: Although significant advancements have been made in the detection, surveillance, and treatment of intracranial aneurysms, research and care can differ vastly based on location. Currently, there is lack of knowledge regarding the trends in literature and how the field is evolving with new technology. Here, we use bibliometric analysis to visualize the knowledge structure of the field and identify global research trends in intracranial aneurysm treatment. METHODS: The Web of Science Core Collection was queried for primary research and review articles related to intracranial aneurysm treatment. Four thousand seven hundred and 2 relevant documents were collected and publications over time on different treatment types and publications and citations of journals were collected. VOS viewer was used for the following: 1) identify relationships between keywords, 2) identify co-authorship patterns among organizations and countries, and 3) analyze citation patterns of countries, organizations, and journals. RESULTS: Our results show that research in flow diversion increased at a rapid rate but tended to have low link strength with keywords related to evaluating patient risk and mortality. The highest publication producing countries were the United States of America, Japan, and China, although China had fewer citations relative to its peers. Korean organizations showed less international collaboration. The USA has been the leader in terms of productivity and collaboration in the field, as have several US-based journals such as Journal of Neurosurgery, Neurosurgery, and World Neurosurgery. CONCLUSIONS: Evaluating the safety of flow diversion treatment remains a pressing area of research. Chinese and Korean organizations may be of interest for global collaborations.

Large-scale rare variant burden testing in Parkinson's disease.

Parkinson's disease has a large heritable component and genome-wide association studies have identified over 90 variants with disease-associated common variants, providing deeper insights into the disease biology. However, there have not been large-scale rare variant analyses for Parkinson's disease. To address this gap, we investigated the rare genetic component of Parkinson's disease at minor allele frequencies <1%, using whole genome and whole exome sequencing data from 7184 Parkinson's disease cases, 6701 proxy cases and 51 650 healthy controls from the Accelerating Medicines Partnership Parkinson's disease (AMP-PD) initiative, the National Institutes of Health, the UK Biobank and Genentech. We performed burden tests meta-analyses on small indels and single nucleotide protein-altering variants, prioritized based on their predicted functional impact. Our work identified several genes reaching exome-wide significance. Two of these genes, GBA1 and LRRK2, have variants that have been previously implicated as risk factors for Parkinson's disease, with some variants in LRRK2 resulting in monogenic forms of the disease. We identify potential novel risk associations for variants in B3GNT3, AUNIP, ADH5, TUBA1B, OR1G1, CAPN10 and TREML1 but were unable to replicate the observed associations across independent datasets. Of these, B3GNT3 and TREML1 could provide new evidence for the role of neuroinflammation in Parkinson's disease. To date, this is the largest analysis of rare genetic variants in Parkinson's disease.

Characterization hiPSC-derived neural progenitor cells and neurons to investigate the role of NOS1AP isoforms in human neuron dendritogenesis.

Abnormal dendritic arbor development has been implicated in a number of neurodevelopmental disorders, such as autism and Rett syndrome, and the neuropsychiatric disorder schizophrenia. Postmortem brain samples from subjects with schizophrenia show elevated levels of NOS1AP in the dorsolateral prefrontal cortex, a region of the brain associated with cognitive function. We previously reported that the long isoform of NOS1AP (NOS1AP-L), but not the short isoform (NOS1AP-S), negatively regulates dendrite branching in rat hippocampal neurons. To investigate the role that NOS1AP isoforms play in human dendritic arbor development, we adapted methods to generate human neural progenitor cells and neurons using induced pluripotent stem cell (iPSC) technology. We found that increased protein levels of either NOS1AP-L or NOS1AP-S decrease dendrite branching in human neurons at the developmental time point when primary and secondary branching actively occurs. Next, we tested whether pharmacological agents can decrease the expression of NOS1AP isoforms. Treatment of human iPSC-derived neurons with d-serine, but not clozapine, haloperidol, fluphenazine, or GLYX-13, results in a reduction in endogenous NOS1AP-L, but not NOS1AP-S, protein expression; however, d-serine treatment does not reverse decreases in dendrite number mediated by overexpression of NOS1AP isoforms. In summary, we demonstrate how an in vitro model of human neuronal development can help in understanding the etiology of schizophrenia and can also be used as a platform to screen drugs for patients.

Enhancing peer support experience for patients discharged from acute psychiatric care: protocol for a randomised controlled pilot trial.

INTRODUCTION: This study will evaluate the effectiveness of an innovative peer support programme. The programme incorporates leadership training, mentorship, recognition and reward systems for peer support workers, and supportive/reminder text messaging for patients discharged from acute (hospital) care. We hypothesise that patients enrolled in the peer support system plus daily supportive/reminder text messages condition will achieve superior outcomes in comparison to other groups. METHODS AND ANALYSIS: This is a prospective, rater-blinded, four-arm randomised controlled trial. 180 patients discharged from acute psychiatric care in Edmonton, Alberta, Canada will be randomised to one of four conditions: (1) enrolment in a peer support system; (2) enrolment in a peer support system plus automated daily supportive/reminder text messages; (3) enrolment in automated daily supportive/reminder text messages alone; or (4) treatment as usual follow-up care. Patients in each group will complete evaluation measures (eg, recovery, general symptomatology and functional outcomes) at baseline, 6 months and 12months. Patient service utilisation data and clinician-rated measures will also be used to gauge patient progress. Patient data will be analysed with descriptive statistics, repeated measures and correlational analyses. The peer support worker experience will be captured using qualitative methods. ETHICS AND DISSEMINATION: The study will be conducted in accordance with the Declaration of Helsinki (Hong Kong Amendment) and Good Clinical Practice (Canadian Guidelines). The study has received ethical clearance from the Health Ethics Research Board of the University of Alberta (Ref # Pro00078427) and operational approval from our regional health authority (AHS- (PRJ) #35293). All participants will provide informed consent prior to study inclusion. The results will be disseminated at several levels, including patients/peer supports, practitioners, academics/researchers, and healthcare organisations. TRIAL REGISTRATION NUMBER: NCT03404882; Pre-results.