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Application of chimeric glucanase comprising mutanase and dextranase for prevention of dental biofilm formation 下载免费PDF全文
Ryoko Otsuka Susumu Imai Takatoshi Murata Yoshiaki Nomura Masaaki Okamoto Hideaki Tsumori Erika Kakuta Nobuhiro Hanada Yasuko Momoi 《Microbiology and immunology》2015,59(1):28-36
Water‐insoluble glucan (WIG) produced by mutans streptococci, an important cariogenic pathogen, plays an important role in the formation of dental biofilm and adhesion of biofilm to tooth surfaces. Glucanohydrolases, such as mutanase (α‐1,3‐glucanase) and dextranase (α‐1,6‐glucanase), are able to hydrolyze WIG. The purposes of this study were to construct bi‐functional chimeric glucanase, composed of mutanase and dextranase, and to examine the effects of this chimeric glucanase on the formation and decomposition of biofilm. The mutanase gene from Paenibacillus humicus NA1123 and the dextranase gene from Streptococcus mutans ATCC 25175 were cloned and ligated into a pE‐SUMOstar Amp plasmid vector. The resultant his‐tagged fusion chimeric glucanase was expressed in Escherichia coli BL21 (DE3) and partially purified. The effects of chimeric glucanase on the formation and decomposition of biofilm formed on a glass surface by Streptococcus sobrinus 6715 glucosyltransferases were then examined. This biofilm was fractionated into firmly adherent, loosely adherent, and non‐adherent WIG fractions. Amounts of WIG in each fraction were determined by a phenol‐sulfuric acid method, and reducing sugars were quantified by the Somogyi–Nelson method. Chimeric glucanase reduced the formation of the total amount of WIG in a dose‐dependent manner, and significant reductions of WIG in the adherent fraction were observed. Moreover, the chimeric glucanase was able to decompose biofilm, being 4.1 times more effective at glucan inhibition of biofilm formation than a mixture of dextranase and mutanase. These results suggest that the chimeric glucanase is useful for prevention of dental biofilm formation. 相似文献
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Masaaki Okamoto Susumu Imai Mayu Miyanohara Wataru Saito Yasuko Momoi Yoshiaki Nomura Tomoko Ikawa Takumi Ogawa Takako Miyabe‐Nishiwaki Akihisa Kaneko Akino Watanabe Shohei Watanabe Misato Hayashi Masaki Tomonaga Nobuhiro Hanada 《Microbiology and immunology》2015,59(9):526-532
Three strains TKU9, TKU49 and TKU50T, were isolated from the oral cavities of chimpanzees (Pan troglodytes). The isolates were all gram‐positive, facultative anaerobic cocci that lacked catalase activity. Analysis of partial 16S rRNA gene sequences showed that the most closely related species was Streptococcus infantis (96.7%). The next most closely related species to the isolates were S. rubneri, S. mitis, S. peroris and S. australis (96.6 to 96.4%). Based on the rpoB and gyrB gene sequences, TKU50T was clustered with other member of the mitis group. Enzyme activity and sugar fermentation patterns differentiated this novel bacterium from other members of the mitis group streptococci. The DNA G + C content of strain TKU50T was 46.7 mol%, which is the highest reported value for members of the mitis group (40–46 mol%). On the basis of the phenotypic characterization, partial 16S rRNA gene and sequences data for two housekeeping gene (gyrB and rpoB), we propose a novel taxa, S. panodentis for TKU 50T (type strain = CM 30579T = DSM 29921T), for these newly described isolates. 相似文献
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Hideki Yoshida Toshihiko Imamura Akiko M. Saito Yoshihiro Takahashi So-ichi Suenobu Daiichiro Hasegawa Takao Deguchi Yoshiko Hashii Hirohide Kawasaki Mikiya Endo Hiroki Hori Nobuhiro Suzuki Yoshiyuki Kosaka Koji Kato Keiko Yumura-Yagi Junichi Hara Megumi Oda Atsushi Sato Keizo Horibe Japan Association of Childhood Leukemia Study 《PloS one》2015,10(8)
Although L-asparaginase related hyperglycemia is well known adverse event, it is not studied whether the profile of this adverse event is affected by intensification of L-asparaginase administration. Here, we analyzed the profile of L-asparaginase related hyperglycemia in a 1,176 patients with pediatric acute lymphoblastic leukemia treated according to the Japan Association of Childhood Leukemia Study ALL-02 protocol using protracted L-asparaginase administration in maintenance phase. We determined that a total of 75 L-asparaginase related hyperglycemia events occurred in 69 patients. Although 17 events (17/1176, 1.4%) developed in induction phase, which was lower incidence than those (10–15%) in previous reports, 45 events developed during the maintenance phase with protracted L-asparaginase administration. Multivariate analysis showed that older age at onset (≥10 years) was a sole independent risk factor for L-asparaginase-related hyperglycemia (P<0.01), especially in maintenance phase. Contrary to the previous reports, obesity was not associated with L-asparaginase-related hyperglycemia. These findings suggest that protracted administration of L-asparaginase is the risk factor for hyperglycemia when treating adolescent and young adult acute lymphoblastic leukemia patients. 相似文献
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Yoshiaki Fujimiya Shinobu Oyama Yoshio Numazaki Nakao Ishida 《Microbiology and immunology》1974,18(5):379-384
In 1970, a great outbreak of hand-foot-and-mouth disease (HFMD) due to Coxsackie A16 virus (Cox A16) occurred throughout Japan. When serologic relationship between the viruses isolated during the epidemic and the prototype strain of the serotype was examined by the tube neutralization test, the crude new isolates were found to be poorly neutralized by both an antiserum against the prototype strain and those against the isolates, although they were neutralized significantly in the plaque reduction test. However, about 2% of virus in crude suspensions of the isolates remained unneutralized even in the plaque reduction test and this fraction could be eliminated by filtering the virus materials through a 100 mμ Millipore filter. Therefore, the difficulty in neutralization of the isolates by the tube method could be accounted for by the presence of aggregated viruses. Even when filtered viruses were used, the reciprocal neutralization kinetic studies revealed a significant serological difference between the isolates and the prototype strain. Such serological properties of the isolates were not influenced by the cell types used for virus isolation or passages. All the results suggest that the Cox A16 isolates from the epidemic of HFMD in Japan, 1970, are serologically different from the prototype strain. 相似文献
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Ohara Chisato Sekiguchi Atsushi Takakura Shu Endo Yuka Tamura Naho Kikuchi Hiroe Maruo Kazushi Sugawara Norio Hatano Kenji Kawanishi Hitomi Funaba Misako Sugawara Ayako Nohara Nobuhiro Kawai Keisuke Fukudo Shin Sudo Nobuyuki Cooper Zafra Yoshiuchi Kazuhiro Ando Tetsuya 《BioPsychoSocial medicine》2020,14(1):1-3
Although fatigue is a common and distressing symptom in cancer survivors, the mechanism of fatigue is not fully understood. Therefore, this study aims to investigate the relation between the fatigue and mindfulness of breast cancer survivors using anxiety, depression, pain, loneliness, and sleep disturbance as mediators. Path analysis was performed to examine direct and indirect associations between mindfulness and fatigue. Participants were breast cancer survivors who visited a breast surgery department at a university hospital in Japan for hormonal therapy or regular check-ups after treatment. The questionnaire measured cancer-related-fatigue, mindfulness, anxiety, depression, pain, loneliness, and sleep disturbance. Demographic and clinical characteristics were collected from medical records. Two-hundred and seventy-nine breast cancer survivors were registered, of which 259 answered the questionnaire. Ten respondents with incomplete questionnaire data were excluded, resulting in 249 participants for the analyses. Our final model fit the data well (goodness of fit index = .993; adjusted goodness of fit index = .966; comparative fit index = .999; root mean square error of approximation = .016). Mindfulness, anxiety, depression, pain, loneliness, and sleep disturbance were related to fatigue, and mindfulness had the most influence on fatigue (β = − .52). Mindfulness affected fatigue not only directly but also indirectly through anxiety, depression, pain, loneliness, and sleep disturbance. The study model helps to explain the process by which mindfulness affects fatigue. Our results suggest that mindfulness has both direct and indirect effects on the fatigue of breast cancer survivors and that mindfulness can be used to more effectively reduce their fatigue. It also suggests that health care professionals should be aware of factors such as anxiety, depression, pain, loneliness, and sleep disturbance in their care for fatigue of breast cancer survivors. This study was registered in the University Hospital Medical Information Network Clinical Trials Registry (UMIN number. 000027720) on June 12, 2017. 相似文献
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Akihiko Shimizu Hiroyuki Tsukagoshi Tsuyoshi Sekizuka Makoto Kuroda Aya Koizumi Masahiro Fujita Yoshiyuki Yamada Nobuhiro Saruki 《Microbiology and immunology》2020,64(9):630-634
Group B streptococcus (GBS) is a leading cause of neonatal infections. Most isolates are β-hemolytic, and their activity is considered to be pivotal for GBS pathogenicity. We report a case of a neonate with meningitis caused by nonhemolytic GBS. The patient developed meningitis 3 days after birth. Genotyping was performed and the characteristics of the strain (GCMC97051) identified by whole genome sequence using next generation sequencing. GCMC97051 possesses genetic alterations such as disruption of cylA by IS1381A insertion and a frameshift mutation in cylE, resulting in a lack of hemolysis. Thus, nonhemolytic GBS can retain the potential to cause invasive infections. 相似文献