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12
result(s) for
"Abe, Shusaku"
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Reprogramming of the histone H3.3 landscape in the early mouse embryo
2021
Epigenetic reprogramming of the zygote involves dynamic incorporation of histone variant H3.3. However, the genome-wide distribution and dynamics of H3.3 during early development remain unknown. Here, we delineate the H3.3 landscapes in mouse oocytes and early embryos. We unexpectedly identify a non-canonical H3.3 pattern in mature oocytes and zygotes, in which local enrichment of H3.3 at active chromatin is suppressed and H3.3 is relatively evenly distributed across the genome. Interestingly, although the non-canonical H3.3 pattern forms gradually during oogenesis, it quickly switches to a canonical pattern at the two-cell stage in a transcription-independent and replication-dependent manner. We find that incorporation of H3.1/H3.2 mediated by chromatin assembly factor CAF-1 is a key process for the de novo establishment of the canonical pattern. Our data suggest that the presence of the non-canonical pattern and its timely transition toward a canonical pattern support the developmental program of early embryos.
Ultra-low-input native ChIP-seq analyses of genome-wide histone H3.3 distribution during early mouse development reveal a CAF-1-dependent transition from a non-canonical pattern in the oocyte and zygote to a canonical distribution at the two-cell stage.
Journal Article
Histone H3K36me2 and H3K36me3 form a chromatin platform essential for DNMT3A-dependent DNA methylation in mouse oocytes
2022
Establishment of the DNA methylation landscape of mammalian oocytes, mediated by the DNMT3A-DNMT3L complex, is crucial for reproduction and development. In mouse oocytes, high levels of DNA methylation occur exclusively in the transcriptionally active regions, with moderate to low levels of methylation in other regions. Histone H3K36me3 mediates the high levels of methylation in the transcribed regions; however, it is unknown which histone mark guides the methylation in the other regions. Here, we show that, in mouse oocytes, H3K36me2 is highly enriched in the X chromosome and is broadly distributed across all autosomes. Upon H3K36me2 depletion, DNA methylation in moderately methylated regions is selectively affected, and a methylation pattern unique to the X chromosome is switched to an autosome-like pattern. Furthermore, we find that simultaneous depletion of H3K36me2 and H3K36me3 results in global hypomethylation, comparable to that of DNMT3A depletion. Therefore, the two histone marks jointly provide the chromatin platform essential for guiding DNMT3A-dependent DNA methylation in mouse oocytes.
DNMT3A is known to methylate DNA at histone H3 lysine 36 (H3K36me3)-marked transcriptionally active regions in mouse oocytes. Here the authors show that DNMT3A is also guided by H3K36me2 to methylate broad domains in genic and intergenic loci, as well as on the X chromosome. These two histone marks together comprise the minimal chromatin signature for global DNA methylation in mouse oocytes.
Journal Article
Photocatalytic uphill conversion of natural gas beyond the limitation of thermal reaction systems
by
Matsumura, Syo
,
Fujita, Takeshi
,
Ishii, Satoshi
in
639/301/299/890
,
639/638/439/890
,
639/638/77/887
2020
Dry reforming of methane is one of the key reactions to exploit natural gas feedstocks by their catalytic conversion to synthesis gas (CH
4
+ CO
2
→ 2H
2
+ 2CO), which is used in the production of transportable liquid fuel. However, this reaction suffers from thermodynamic conversion limits and high thermal energy requirements. Herein we report that a SrTiO
3
-supported rhodium (Rh/STO) catalyst efficiently promotes methane reforming under ultraviolet light irradiation without heat supply at low temperatures, which cannot be achieved by conventional thermal catalysis. The photoexcited holes and electrons are used for CH
4
oxidation over STO and CO
2
reduction over rhodium, respectively. Isotope analysis clarified that the lattice oxygens (O
2−
) act as mediator to drive dry reforming of methane. The materials design of Rh/STO can be extended in principle to diverse uphill reactions that utilize photon energy to obtain valued products from different carbon resources.
Despite its potential, catalytic dry reforming of methane has not yet reached practical application due to high thermal energy requirements. Now, a photocatalytic method is introduced based on strontium titanate-supported rhodium nanoparticles that afford syngas production solely under light irradiation.
Journal Article
Identification of commonly altered genes between in major depressive disorder and a mouse model of depression
2017
The heterogeneity of depression (due to factors such as varying age of onset) may explain why biological markers of major depressive disorder (MDD) remain uncertain. We aimed to identify gene expression markers of MDD in leukocytes using microarray analysis. We analyzed gene expression profiles of patients with MDD (age ≥50, age of depression onset <50) (N = 10, depressed state; N = 13, remitted state). Seven-hundred and ninety-seven genes (558 upregulated, 239 downregulated when compared to those of 30 healthy subjects) were identified as potential markers for MDD. These genes were then cross-matched to microarray data obtained from a mouse model of depression (676 genes, 148 upregulated, 528 downregulated). Of the six common genes identified between patients and mice, five genes (SLC35A3, HIST1H2AL, YEATS4, ERLIN2, and PLPP5) were confirmed to be downregulated in patients with MDD by quantitative real-time polymerase chain reaction. Of these genes, HIST1H2AL was significantly decreased in a second set of independent subjects (age ≥20, age of onset <50) (N = 18, subjects with MDD in a depressed state; N = 19, healthy control participants). Taken together, our findings suggest that HIST1H2AL may be a biological marker of MDD.
Journal Article
Intraoperative use of lateral spread response measurement in the upper orbicularis oculi and mandibular muscles in patients with hemifacial spasm after botulinum toxin treatment
2025
Background
Following repeated botulinum toxin (BTX) treatments, patients with hemifacial spasm (HFS) are recommended to undergo microvascular decompression (MVD) for a permanent cure. Intraoperative lateral spread response (LSR) monitoring is important to improve surgical outcomes. However, LSR monitoring during MVD surgery in HFS patients who have previously received BTX is challenging, since the muscles typically used to assess the LSR are paralyzed. Here, we describe our use of the upper part of the orbicularis oculi and mentalis muscles for intraoperative monitoring of the LSR during MVD in HFS patients following BTX treatment.
Methods
HFS patients who underwent MVD surgery were divided into two groups based on their history of BTX treatment: BTX+ and BTX- groups. In the BTX+ group, MVD was performed at least 3 months after the last BTX injection. We measured LSR morphology, including the number of spikes, their duration, and maximum amplitude in all patients. We also measured intraoperative LSR disappearance rate, and the cure rate of HFS at the final follow-up (over 1 year after surgery).
Results
Although the waveforms showed a trend toward shorter durations with mandibular branch stimulation in the BTX+ group, there was no difference in the number of spikes or maximum amplitude values. There was no increase in LSR dysmetria after BTX treatment (BTX+ group: 32.8% vs. BTX- group: 31.9%). There was also no difference in intraoperative LSR disappearance rate between the two groups (BTX+ group: 68.3% vs. BTX- group: 74.6%).
Conclusion
Intraoperative LSR monitoring using the upper part of the orbicularis oculi muscle and the mentalis muscle at an interval of at least 3 months after the last BTX treatment might be a feasible monitoring technique during MVD for HFS.
Journal Article
Lyotropic ordering for high proton conductivity in sulfonated semialiphatic polyimide thin films
2019
The influence of the semialiphatic backbone on molecular ordering and proton conductivity was investigated in comparison to the rigid aromatic backbone in highly proton-conductive organized polyimide thin films. We newly synthesized two alkyl-sulfonated semialiphatic polyimides (ASSPIs) with different molecular weights and investigated their molecular organized structure, proton conductivity, water uptake, and the dissociation state of protons from sulfonic acid groups in thin films by in situ measurements for grazing incidence small-angle X-ray scattering (GISAXS), quartz crystal microbalance (QCM), fourier transform infrared (FT-IR) spectra, and impedance spectra. Declining planarity in the semialiphatic backbone reduced the aggregative character and molecular ordering in the lyotropic liquid-crystalline (LC) structure. However, the higher-molecular-weight ASSPI exhibited the oriented lamellar structure despite the lower planarity of the main chain. The proton conductivity of the oriented lamellar thin film had more than half an order of magnitude higher value of 1.5 × 10-1 S cm-1 than did the nonoriented lamellar thin film (3.0 × 10-2 S cm-1) at 25 °C and 95% RH. These results indicate that in sulfonated polyimide thin films, the lamellar orientation greatly contributes to the high proton conductivity in ASSPI thin films.
Journal Article
Impaired hippocampal spinogenesis and neurogenesis and altered affective behavior in mice lacking heat shock factor 1
2011
Aberrant transcriptional regulation in the brain is thought to be one of the key components of the pathogenesis and pathophysiology of neuropsychiatric disorders. Heat shock factors (HSFs) modulate cellular homeostasis through the control of gene expression. However, the roles of HSFs in brain function have yet to be elucidated fully. In the present study, we attempted to clarify the role of HSF1-mediated gene regulation in neuronal and behavioral development using HSF1-deficient (HSF1⁻/⁻) mice. We found granule neurons of aberrant morphology and impaired neurogenesis in the dentate gyrus of HSF1⁻/⁻ mice. In addition, HSF1⁻/⁻ mice showed aberrant affective behavior, including reduced anxiety and sociability but increased depression-like behavior and aggression. Furthermore, HSF1 deficiency enhanced behavioral vulnerability to repeated exposure to restraint stress. Importantly, rescuing the HSF1 deficiency in the neonatal but not the adult hippocampus reversed the aberrant anxiety and depression-like behaviors. These results indicate a crucial role for hippocampal HSF1 in neuronal and behavioral development. Analysis of the molecular mechanisms revealed that HSF1 directly modulates the expression of polysialyltransferase genes, which then modulate polysialic acid-neural cell adhesion molecule (PSA-NCAM) levels in the hippocampus. Enzymatic removal of PSA from the neonatal hippocampus resulted in aberrant behavior during adulthood, similar to that observed in HSF1⁻/⁻ mice. Thus, these results suggest that one role of HSF1 is to control hippocampal PSA-NCAM levels through the transcriptional regulation of polysialyltransferases, a process that might be involved in neuronal and behavioral development in mice.
Journal Article
Roles of double-balloon endoscopy in the diagnosis and treatment of Crohn's disease: a multicenter experience
by
Nishida, Tsutomu
,
Ebara, Ryoichi
,
Komori, Masato
in
Abdominal Surgery
,
Adult
,
adverse effects
2010
Background Double-balloon endoscopy (DBE) examinations are not yet widely accepted as routine procedures for examining the small bowel of patients with Crohn's disease (CD). Aim To evaluate the feasibility and usefulness of DBE for CD in tertiary-care hospitals. Methods Between July 2004 and September 2008, 1444 DBE procedures were performed for 704 patients in 6 tertiary-care hospitals. Patient profile, indication, diagnosis and treatment of DBE were evaluated using a multicenter database. Results DBE examinations were most frequently performed in 75 patients with CD, corresponding to 10.5% of all the patients examined by DBE. Fifty patients were diagnosed with CD before DBE, while DBE was performed for the diagnosis of 25 new CD patients. Small bowel lesions were often detected even when the terminal ileum was not involved. In the 75 patients, 21 patients were asymptomatic at the time of DBE examinations. Active inflammatory lesions were detected in 51.2% of the CD patients, and were even detected in 33.3% of the asymptomatic CD patients. The treatment was altered in 53.3% of the CD patients after the DBE evaluation. No severe complications were experienced. Conclusions DBE procedures can be safely performed in patients with CD and should be considered for the precise evaluation of and to determine the treatment strategy for CD.
Journal Article
A case of juvenile eosinophilic cholangitis: Rapid peripheral blood hypereosinophilia after admission leading to diagnosis
2021
A 15‐year‐old boy was referred to our hospital with elevated hepatobiliary enzyme levels and jaundice. Magnetic resonance cholangiopancreatography performed at the previous medical facility revealed a stricture of the intrahepatic and extrahepatic bile duct. Computed tomography showed dilatation and wall thickness of the intrahepatic bile ducts. Primary sclerosing cholangitis or cholangiocarcinoma was suspected. Endoscopic retrograde cholangiopancreatography (ERCP) showed stricture in the intrahepatic and extrahepatic bile duct. On admission, the eosinophil count in the peripheral blood was normal; however, rapid hypereosinophilia in the peripheral blood was observed after admission, leading us to suspect eosinophilic cholangitis (EC). A bile duct biopsy showed inflammatory cells and eosinophil infiltration during a second ERCP. The patient was diagnosed with EC based on histopathology. Eosinophilic cholangitis was diagnosed based on the elevated blood eosinophil count after admission and bile duct pathology.
Journal Article
Temperature and Food Availability Differentially Affect the Production of Antimicrobial Compounds in Oral Secretions Produced by Two Species of Burying Beetle
by
Akahane, Shusaku
,
Shaffer, Julie J
,
Jacques, Betty J
in
Agriculture
,
ambient temperature
,
Animal and plant ecology
2009
Carrion beetles of the subfamily Nicrophorinae search and bury a carcass that they utilize for reproduction. After burial, the carcass is coated with oral secretions that delay its decomposition. Previously, oral secretions of Nicrophorus marginatus were found to show antimicrobial activity, whereas secretion of N. carolinus lacked significant activity. Here, we tested the effects of temperature, sex of the beetle, and food type on the antimicrobial properties of oral secretions of both species. Unlike previous findings, we found that oral secretions of N. carolinus had antimicrobial activity. Temperature had significant effects on the amount of secretion protein. When protein concentrations were standardized to 1 μ/ml, N. marginatus secretions had higher antimicrobial activity at cooler temperatures, while N. carolinus had higher activity at warmer ones. The sex of the beetle did not affect antimicrobial activity for either species. Beetles of both species that were fed whole rats contained more protein in their oral secretions than beetles fed with equally sized pieces of raw ground beef. After standardizing the resulting protein concentrations to 1 μg/ml, antimicrobial activity of oral secretion increased for N. carolinus after rat feeding, but not for N. marginatus. Our results highlight key ecological differences between these closely related species. In addition, they demonstrate the importance of experiments being conducted under varying environmental conditions when evaluating species for potential antimicrobial compounds.
Journal Article