Publications by authors named "M H Osakabe"

Beam-divergence characteristics of single negative ion beamlet have been experimentally investigated with a superimposition of a controlled perturbation of a radio frequency wave (RF) field in a filament-arc discharge negative ion source. Oscillations of a negative-ion beamlet width and axis responding to the RF perturbation were observed, which may be a cause of the larger beam divergence angle of the RF negative ion source for ITER. It is pointed out that the oscillation of the beamlet width depends on the perveance and on an RF frequency such that the oscillation is suppressed at perveance-matched conditions and at low RF frequency.

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Article Synopsis
  • The study focuses on understanding the molecular changes in adenoma and carcinoma components of colorectal tumors to better grasp early cancer development.
  • Researchers analyzed genetic alterations in 46 cases of microsatellite-stable colorectal cancer using genome-wide methods, identifying two distinct subgroups based on the frequency of somatic copy number alterations (SCNAs).
  • Findings revealed that while both adenoma and carcinoma components shared common mutations, significant SCNAs and increased TP53 mutations were essential for the transition from adenoma to carcinoma within these tumors.
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Background: Gastric foveolar type neoplasia is a rare histological variant of gastric tumors. It is very difficult to differentiate between benign and malignant intraepithelial foveolar neoplasia (IFN). Although limited molecular alterations have been identified in IFNs, somatic copy number alterations (SCNAs), which are linked to tumor progression, have not been systematically evaluated in IFN.

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Background: The prognostic value of the pathological response to preoperative chemoradiotherapy (CRT) in rectal cancer (RC) remains unknown.

Objectives: We aimed to assess the predictive value of the response to CRT that was derived from an evaluation of the histological findings (whole-section vs. representative-section sampling) and attempted to determine an objective cut-off value for the tumor regression grade (TRG).

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Mutations in the TP53 gene, most commonly observed in colorectal cancer (CRC), play an essential role in colorectal carcinogenesis. Although p53 immunohistochemical (IHC) expression patterns have been argued to serve as an excellent surrogate marker for TP53 mutations, its performance has not been confirmed in CRC. We aimed to determine whether p53 IHC expression patterns accurately predict TP53 mutation status as examined by next-generation sequencing (NGS).

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