Masato Suzuki

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This paper presents a precise system for handwritten Chinese and Japanese character recognition. Before extracting directional element feature (DEF) from each character image, transformation based on partial inclination detection (TPID) is used to reduce undesired effects of degraded images. In the recognition process, city block distance with deviation(More)
CagA protein is a major virulence factor of Helicobacter pylori, which is delivered into gastric epithelial cells and elicits growth factor-like responses. Once within the cells, CagA is tyrosine phosphorylated by Src family kinases and targets host proteins required to induce the cell responses. We show that the phosphorylated CagA binds Crk adaptor(More)
Shigella use a special mechanism to invade epithelial cells called 'the trigger mechanism of entry', which allows epithelial cells to trap several bacteria simultaneously. On contact, Shigella deliver effectors into epithelial cells through the type III secretion system. Here, we show that one of the effectors, IpgB1, has a pivotal role in producing(More)
CagA, a major virulence factor of Helicobacter pylori (Hp), is delivered into gastric epithelial cells and exists in phosphorylated and nonphosphorylated forms. The biological activity of the phosphorylated form is well established; however, function(s) of the nonphosphorylated form remain elusive. Here, we report that a conserved motif in the C-terminal(More)
Shigella, the causative agent of bacillary dysentery, is capable of inducing the large scale membrane ruffling required for the bacterial invasion of host cells. Shigella secrete a subset of effectors via the type III secretion system (TTSS) into the host cells to induce membrane ruffling. Here, we show that IpgB1 is secreted via the TTSS into epithelial(More)
Studies on the pathogenesis of Salmonella enterica serovar Typhimurium infections in mice have revealed the presence of two prominent virulence characteristics-the invasion of the nonphagocytic cells to penetrate the intestinal epithelium and the proliferation within host phagocytic cells to cause a systemic spread and the colonization of host organs. We(More)
Some pathogenic bacteria actually invade the cytoplasm of their target host cells. Invasive bacteria acquire the propulsive force to move by recruiting actin and inducing its polymerization. Here we show that Shigella movement within the cytoplasm was severely hindered by microtubules and that the bacteria destroyed surrounding microtubules by secreting(More)
Many bacterial pathogens can enter various host cells and then survive intracellularly, transiently evade humoral immunity, and further disseminate to other cells and tissues. When bacteria enter host cells and replicate intracellularly, the host cells sense the invading bacteria as damage-associated molecular patterns (DAMPs) and pathogen-associated(More)
Colonization of the gastric pits in the stomach by Helicobacter pylori (Hp) is a major risk factor for gastritis, gastric ulcers, and cancer. Normally, rapid self-renewal of gut epithelia, which occurs by a balance of progenitor proliferation and pit cell apoptosis, serves as a host defense mechanism to limit bacterial colonization. To investigate how Hp(More)
Chronic infection of Helicobacter pylori in the stomach mucosa with translocation of the bacterial cytotoxin-associated gene A (CagA) effector protein via the cag-Type IV secretion system (TFSS) into host epithelial cells are major risk factors for gastritis, gastric ulcers, and cancer. The blood group antigen-binding adhesin BabA mediates the adherence of(More)