Publications by authors named "Yumiko Fujii"

There are two main characteristics of visual information processing when viewing an image by scrolling on a small screen: viewing the image sequentially, section by section, owing to the limited visible area, and moving the image to view the desired section of the image. In this study, we investigated the effects of these characteristics on the encoding of object location. The participants were required to observe an image containing 10 objects under three viewing conditions without a time limit and to recall the location of the target object.

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In contrast to the robust proliferation exhibited following acute liver injury, hepatocytes exhibit long-lasting proliferative activity in chronic liver injury. The mechanistic differences between these distinct modes of proliferation are unclear. Hepatocytes exhibited robust proliferation that peaked at 2 days following partial hepatectomy in mice, but this proliferation was completely inhibited by hepatocyte-specific expression of MadMyc, a Myc-suppressing chimeric protein.

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A previous study reported that reaction times (RTs) and the amplitude of the P1 component of event-related potentials (ERPs) elicited by visual stimuli decreased during visuospatial implicit sequence learning in the serial reaction time task, suggesting that sequence learning reduces attentional demands on visual stimulus processing. In the present study, to evaluate the replicability of the previous finding and to obtain a better understanding of how visual stimulus processing is affected by visuospatial implicit sequence learning, we measured ERPs and neural synchrony from 44 participants during a modified serial reaction time task which controlled for a possible confounding factor in the previous study (i.e.

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Hepatocellular carcinoma (HCC) activates platelets through the action of adjacent sinusoidal cells. Activated platelets bind to tumor-associated endothelial cells and release growth factors that promote tumor progression. We hypothesized that platelets encapsulated with tumor inhibitors would function as drug carriers for tumor therapy.

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Article Synopsis
  • Nonalcoholic fatty liver disease (NAFLD) may lead to serious conditions like cirrhosis and liver cancer, but its progression mechanisms are not fully understood.
  • This study explored how reduced portal circulation affects nonalcoholic steatohepatitis (NASH) using a mouse model with congenital portosystemic shunt (PSS), finding that PSS worsened fibrosis and ductular reactions.
  • The findings suggest that decreased portal circulation leads to tissue hypoxia and contributes to liver fibrosis in NASH, highlighting the significance of blood flow in liver health.
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Every day we perceive pictures on our mobile phones and scroll through images within a limited space. At present, however, visual perception via image scrolling is not well understood. This study investigated the nature of visual perception within a small window frame.

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Chronic infection with Helicobacter pylori cagA-positive strains is causally associated with the development of gastric diseases, most notably gastric cancer. The cagA-encoded CagA protein, which is injected into gastric epithelial cells by bacterial type IV secretion, undergoes tyrosine phosphorylation at the Glu-Pro-Ile-Tyr-Ala (EPIYA) segments (EPIYA-A, EPIYA-B, EPIYA-C, and EPIYA-D), which are present in various numbers and combinations in its C-terminal polymorphic region, thereby enabling CagA to promiscuously interact with SH2 domain-containing host cell proteins, including the prooncogenic SH2 domain-containing protein tyrosine phosphatase 2 (SHP2). Perturbation of host protein functions by aberrant complex formation with CagA has been considered to contribute to the development of gastric cancer.

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In the human visual system, different attributes of an object are processed separately and are thought to be then temporarily bound by attention into an integrated representation to produce a specific response. However, if such representations existed in the brain for arbitrary multi-attribute objects, a combinatorial explosion problem would be unavoidable. Here, we show that attention may bind features of different attributes only in pairs and that bound feature pairs, rather than integrated object representations, are associated with responses for unfamiliar objects.

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Helicobacter pylori cagA-positive strain delivers the CagA oncoprotein into gastric epithelial cells and at the same time elicits stomach inflammation. To experimentally investigate the pathophysiological interplay between CagA and inflammation, transgenic mice systemically expressing the bacterial cagA gene were treated with a colitis inducer, dextran sulfate sodium (DSS). Compared with control mice, DSS-induced colitis was markedly deteriorated in cagA-transgenic mice.

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SUMMARY Strongyloides venezuelensis is a parasitic nematode that infects rodents. Although Strongyloides species described to date are known to exhibit parthenogenetic reproduction in the parasitic stage of their life cycle and sexual reproduction in the free-living stage, we did not observe any free-living males in S. venezuelensis in our strain, suggesting that the nematode is likely to depend on parthenogenetic reproduction.

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SHP2 is a ubiquitously expressed protein tyrosine phosphatase, deregulation of which is associated with malignant neoplasms and developmental disorders. SHP2 is required for full activation of RAS-Erk signaling in the cytoplasm and is also present in the nucleus, where it promotes Wnt target gene activation through dephosphorylation of parafibromin. SHP2 is distributed both to the cytoplasm and nucleus at low cell density but is excluded from the nucleus at high cell density.

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Intestinal metaplasia of the stomach, a mucosal change characterized by the conversion of gastric epithelium into an intestinal phenotype, is a precancerous lesion from which intestinal-type gastric adenocarcinoma arises. Chronic infection with Helicobacter pylori is a major cause of gastric intestinal metaplasia, and aberrant induction by H. pylori of the intestine-specific caudal-related homeobox (CDX) transcription factors, CDX1 and CDX2, plays a key role in this metaplastic change.

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Chronic infection with cagA-positive Helicobacter pylori is associated with the development of atrophic gastritis, peptic ulcers, and gastric adenocarcinoma. The cagA gene product CagA is injected into gastric epithelial cells, where it undergoes tyrosine phosphorylation by Src family kinases. Translocated CagA disturbs cellular functions by physically interacting with and deregulating intracellular signaling transducers through both tyrosine phosphorylation-dependent and -independent mechanisms.

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Helicobacter pylori contributes to the development of peptic ulcers and atrophic gastritis. Furthermore, H. pylori strains carrying the cagA gene are more virulent than cagA-negative strains and are associated with the development of gastric adenocarcinoma.

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The CagA protein of Helicobacter pylori, which is injected from the bacteria into bacteria-attached gastric epithelial cells, is associated with gastric carcinoma. CagA is tyrosine-phosphorylated by Src family kinases, binds the SH2 domain-containing SHP-2 phosphatase in a tyrosine phosphorylation-dependent manner, and deregulates its enzymatic activity. We established AGS human gastric epithelial cells that inducibly express wild-type or a phosphorylation-resistant CagA, in which tyrosine residues constituting the EPIYA motifs were substituted with alanines.

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