Journal of Neuropathology and Experimental Neurology最新文献

Central nervous system (CNS) metastases represent a small portion of pediatric CNS neoplasms and data surrounding this condition with high morbidity is scarce. Single institutional archival institutional pathology records between 1999 and 2022 were searched for patients over 21 years old and younger with CNS, dura, cranial nerve, CSF, or leptomeningeal metastases; 41 cases were identified. We documented primary tumor types and locations, metastasis locations, types of invasion (direct extension vs distant metastasis), times from imaging or pathologic diagnosis to CNS involvement, and outcomes. Distant metastasis was the most common mechanism of metastasis (n = 32, 78%). Interval times to CNS metastasis varied by both tumor type and primary tumor location. In this cohort, osteosarcoma portended the shortest survival following CNS metastasis. This study highlights the diverse mechanisms and locations of CNS involvement in pediatric CNS metastases and illuminates a need for varied monitoring strategies when considering primary tumor type and anatomic location.

The pathobiology of tau is of great importance for understanding the mechanisms of neurodegeneration in aging and age-associated disorders such as Alzheimer disease (AD) and frontotemporal dementias. It is critical to identify neuronal populations and brain regions that are vulnerable or resistant to tau pathological changes. Pick disease (PiD) is a three-repeat (3R) tauopathy that belongs to the group of frontotemporal lobar degenerations. The neuropathologic changes of PiD are characterized by globular tau-positive neuronal intracytoplasmic inclusions, called Pick bodies, in the granule cells of the dentate gyrus and frontal and temporal neocortices, and ballooned neurons, named Pick neurons, in the neocortex. In the present study, we examined 13 autopsy-confirmed cases of PiD. Using immunohistochemistry for phospho-tau (AT8) and 3R tau isoform, all PiD cases demonstrated extensive lesions involving the hippocampus and neocortex. However, the lateral geniculate body (LGB) is spared of significant tau lesions in contrast to the neighboring hippocampus and other thalamic nuclei. Only 1 PiD case (7.7%) had tau-positive neurons, and 4 cases had tau-positive neurites (31%) in the LGB. By contrast, the LGB does consistently harbor tau lesions in other tauopathies including progressive supranuclear palsy, corticobasal degeneration, and AD.

Cerebral infarction (CI) is one of the leading causes of disability and death. LncRNAs are key factors in CI progression. Herein, we studied the function of long noncoding RNA KCNQ1OT1 in CI patient plasma samples and in CI models. Quantitative real-time PCR and Western blotting tested gene and protein expressions. The interactions of KCNQ1OT1/PTBP1 and miR-16-5p were analyzed using dual-luciferase reporter and RNA immunoprecipitation assays; MTT assays measured cell viability. Cell migration and angiogenesis were tested by wound healing and tube formation assays. Pathological changes were analyzed by triphenyltetrazolium chloride and routine staining. We found that KCNQ1OT1 and PTBP1 were overexpressed and miR-16-5p was downregulated in CI patient plasma and in oxygen-glucose deprived (OGD) induced mouse brain microvascular endothelial (bEnd.3) cells. KCNQ1OT1 knockdown suppressed pro-inflammatory cytokine production and stimulated angiogenic responses in OGD-bEnd.3 cells. KCNQ1OT1 upregulated PTBP1 by sponging miR-16-5p. PTBP1 overexpression or miR-16-5p inhibition attenuated the effects of KCNQ1OT1 knockdown. PTBP1 silencing protected against OGD-bEnd.3 cell injury by enhancing SIRT1. KCNQ1OT1 silencing or miR-16-5p overexpression also alleviated ischemic injury in a mice middle cerebral artery occlusion model. Thus, KCNQ1OT1 silencing alleviates CI by regulating the miR-16-5p/PTBP1/SIRT1 pathway, providing a theoretical basis for novel therapeutic strategies targeting CI.

To determine the incidence of phosphorylated α-synuclein (p-syn) in skin nerves in very old subjects who are prone to developing incidental Lewy bodies, we prospectively performed skin biopsies on 33 elderly subjects, including 13 (>85 years old) and 20 patients (>70 years) suspected of having an acquired small fiber neuropathy. All subjects underwent neurological examination prior to the biopsy. Two screened female subjects (ages 102 and 98 years) were excluded from the study because they showed evidence of a slight bradykinetic-rigid extrapyramidal disorder on neurological examination and were not considered healthy; both showed p-syn in skin nerves. We did not identify p-syn in skin nerves in the remaining 31 subjects. A PubMed analysis of publications from 2013 to 2023 disclosed 490 healthy subjects tested for skin p-syn; one study reported p-syn in 4 healthy subjects, but the remaining subjects tested negative. Our data underscore the virtual absence of p-syn in skin nerves of healthy controls, including those who are very elderly. These data support skin biopsy as a highly specific tool for identifying an underlying synucleinopathy in patients in vivo.

In recent years, brain banks have become valuable resources for examining the molecular underpinnings of various neurological and psychological disorders including Alzheimer disease and Parkinson disease. However, the availability of brain tissue has significantly declined. Proper collection, preparation, and preservation of postmortem autopsy tissue are essential for optimal downstream brain tissue distribution and experimentation. Collaborations between brain banks through larger networks such as NeuroBioBank with centralized sample request mechanisms promote tissue distribution where brain donations are disproportionately lower. Collaborations between brain banking networks also help to standardize the brain donation and sample preparation processes, ensuring proper distribution and experimentation. Ethical brain donation and thorough processing enhances the responsible conduct of scientific studies. Education and outreach programs that foster collaboration between hospitals, nursing homes, neuropathologists, and other research scientists help to alleviate concerns among potential brain donors. Furthermore, ensuring that biorepositories accurately reflect the true demographics of communities will result in research data that reliably represent populations. Implementing these measures will grant scientists improved access to brain tissue, facilitating a deeper understanding of the neurological diseases that impact millions.

The World Health Organization has updated their classification system for the diagnosis of gliomas, combining histological features with molecular data including isocitrate dehydrogenase 1 and codeletion of chromosomal arms 1p and 19q. 1p/19q codeletion analysis is commonly performed by fluorescence in situ hybridization (FISH). In this study, we developed a 57-gene targeted next-generation sequencing (NGS) panel including 1p/19q codeletion detection mainly to assess diagnosis and potential treatment response in melanoma, gastrointestinal stromal tumor, and glioma patients. Loss of heterozygosity analysis was performed using the NGS method on 37 formalin-fixed paraffin-embedded glioma tissues that showed 1p and/or 19q loss determined by FISH. Conventional methods were applied for the validation of some glioma-related gene mutations. In 81.1% (30 of 37) and 94.6% (35 of 37) of cases, 1p and 19q were found to be in agreement whereas concordance for 1p/19q codeletion and no 1p/19q codeletion was found in 94.7% (18 of 19) and 94.4% (17 of 18) of cases, respectively. Overall, comparing NGS results with those of conventional methods showed high concordance. In conclusion, the NGS panel allows reliable analysis of 1p/19q codeletion and mutation at the same time.