Biology subjects

Nishizawa, Y.

Publications and source records attributed to Nishizawa, Y..

4 recordsLinked to original sources

bioRxiv2025

Glial Contribution to the Pathogenesis of Post-Operative Delirium Revealed by Multi-omic Analysis of Brain Tissue from Neurosurgery Patients

Post-operative delirium (POD) is a common complication after surgery especially in elderly patients, characterized by acute disturbances in consciousness and cognition, which negatively impacts long-term outcomes. Effective treatments remain elusive due to the unclear pathophysiology of POD. To address the knowledge gap, we investigated DNA methylation profiles and gene expression changes in brain cells from POD and non-POD patients who underwent brain resection surgery for medication refractory epilepsy. DNA methylation analysis revealed alteration in epigenetic status of immune and inflammation-related genes. Single-nucleus RNA sequencing (snRNAseq) identified POD-specific glial cell alterations, particularly in microglia, where neuroinflammation was strongly enhanced, consistent with epigenetic findings. Astrocytes exhibited changes in synapse-related functions and migration. Furthermore, downstream analysis indicated similarities between POD-associated glial cell states and pathologies such as encephalitis and dementia. Overall, this study--the first multi-omics analysis of brain tissue from POD patients--provides direct evidence of glial cell contributions to POD pathogenesis, and highlights potential therapeutic targets.

neuroscience↗

bioRxiv2024

Chromosome-scale genome assembly of acerola (Malpighia emarginata DC.)

Acerola (Malpighia emarginata DC.) is a tropical evergreen shrub that produces vitamin C-rich fruits. Increasing fruit nutrition is one of the main targets of acerola breeding programs. Genomic tools have been shown to accelerate plant breeding even in fruiting tree species, which generally have a long life cycle; however, the availability of genomic resources in acerola, so far, has been limited. In this study, as a first step toward developing an efficient breeding technology for acerola, we established a chromosome-scale genome assembly of acerola using high-fidelity long-read sequencing and genetic mapping. The resultant assembly comprises 10 chromosome-scale sequences that span a physical distance of 1,032.5 Mb and contain 35,892 predicted genes. Phylogenetic analysis of genome-wide SNPs in 60 acerola breeding materials revealed three distinct genetic groups. Overall, the genomic resource of acerola developed in this study, including its genome and gene sequences, genetic map, and phylogenetic relationship among breeding materials, will not only be useful for acerola breeding but will also facilitate genomic and genetic studies on acerola and related species.

genomics↗

bioRxiv2024

The bispectral EEG (BSEEG) method quantifies post-operative delirium-like states in young and aged mice after head mount implantation surgery

Delirium, a syndrome characterized by an acute change in attention, awareness, and cognition, is commonly observed in older adults and has multiple potential triggers, including illness, drug, trauma, and surgery. There are few quantitative monitoring methods in clinical settings. We developed the bispectral electroencephalography (BSEEG) method in clinical research that can detect the presence of and quantify the severity of delirium using a novel algorithm. In the pre-clinical model, we reported that the BSEEG method can capture a delirium-like state in mice following LPS administration. However, its application to post-operative delirium (POD) has not yet been validated in animal experiments. Therefore, this study aimed to create a POD model mouse with the BSEEG method by monitoring BSEEG scores after EEG head-mount implantation surgery throughout the recovery phase. We compared the BSEEG scores of C57BL/6J young (2-3 months old) with aged (18-19 months old) mice for quantitative evaluation of the delirium-like state after the surgery. Postoperatively, both groups showed increased BSEEG scores and a loss of regular diurnal changes in BSEEG scores every daytime and night. In young mice, BSEEG scores and regular diurnal changes recovered relatively quickly to baseline by around postoperative day 3. On the other hand, aged mice had prolonged increases in postoperative BSEEG scores and it reached steady state only after around postoperative day 8. This study suggests the BSEEG method can be utilized to quantitatively evaluate POD and also assess the effect of aging on recovery from POD in pre-clinical model.

neuroscience↗

bioRxiv2021

Chitin-induced systemic disease resistance in rice requires both OsCERK1 and OsCEBiP and is mediated via perturbation of cell-wall biogenesis in leaves

O_LIChitin is a well-known elicitor of disease resistance whose recognition by plants is crucial to perceive fungal infections. Chitin can induce both a local immune response and a systemic disease resistance when provided as a supplement in soils. Unlike local immune responses, how chitin-induced systemic disease resistance is deployed has not been studied in detail. C_LIO_LIIn this study, we evaluated systemic disease resistance against the fungal pathogen Bipolaris oryzae by performing a transcriptome analysis and monitoring cell-wall composition in rice plants grown in chitin-supplemented soils. We also examined the local immune response to chitin by measuring the production of reactive oxygen species in leaves. C_LIO_LIChitins induced both local immune response and systemic disease resistance with differing requirements for the receptors OsCERK1 and OsCEBiP. Transcriptome analysis suggested that a perturbation in cell-wall biogenesis is involved in the induction of systemic disease resistance, an idea which was supported by the induction of disease resistance by treatment with a cellulose biosynthesis inhibitor and alterations of cell-wall composition. C_LIO_LIThese findings suggest that chitin-induced systemic disease resistance in rice is caused by a perturbation of cell-wall biogenesis in leaves through long-distance signalling after recognition of chitins by OsCERK1 and OsCEBiP. C_LI

plant biology↗