Publications by authors named "Kyosuke Yokoyama"

Here we present a "breathing" vessel consisting of expanded polytetrafluoroethylene, which allows gas exchange but no liquid permeation. The bacterial culture inside needs only agitation to promote air supply. Using this setup, a Bacillus subtilis cell factory for scyllo-inositol production grew to produce scyllo-inositol efficiently.

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Unlabelled: Mesophilic enzymes, which are active at moderate temperatures, may dominate enzymatic reactions even in the presence of thermophilic crude enzymes. This study was conducted to investigate this hypothesis with mesophilic inositol dehydrogenases (IolG and IolX) produced in HTA426. To ensure the efficient production of mesophilic enzymes, we first screened for promoters induced at moderate temperatures using transcriptome analysis and identified four genes highly expressed at 30°C in the thermophile.

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Porphyromonas gingivalis gingipains is suspected to be one of the most important causative agents of periodontitis. We postulated that the inhibition of gingipains may reduce the pathogenic nature of P. gingivalis.

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In vitro studies suggest that enamel matrix derivative (EMD) affects the early stages of osteogenic maturation by stimulating bone cell proliferation. In the present study, we evaluated the effects of EMD and beta-tricalcium phosphate (beta-TCP) on bone augmentation within a titanium cap in rabbit calvaria, using 14 adult male Japanese white rabbits. The calvarium was exposed, a circular groove prepared, the marrow penetrated, and a standard hemispherical titanium cap placed in the groove.

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Several studies have demonstrated a close association between Streptococcus (S.) anginosus infection and head and neck cancer. Accumulation of 8-hydroxy-deoxyguanosine (8-OHdG), which may result from the continuous generation of reactive oxygen species associated with chronic inflammation, has been reported in human preneoplastic lesions and in cancerous tissues.

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