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41.
Oral Candida Mannan Concentrations Correlate with Symptoms/Signs of Ill Health and the Immune Status
Hakoyama Yusuke Yamada Shin-ichi Nishimaki Fumihiro Hayashi Kiyonori Koizumi Tomonobu Kurita Hiroshi 《Mycopathologia》2020,185(4):629-637
Mycopathologia - A relationship has been proposed between increases in oral Candida concentrations and host immunity. Therefore, the present study was conducted to investigate the relationship... 相似文献
42.
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
43.
Yoshimasa Taniguchi Yasuko Matsukura Harumi Taniguchi Hideki Koizumi Mikio Katayama 《Bioscience, biotechnology, and biochemistry》2013,77(10):1684-1694
The bitter acids in hops (Humulus lupulus L.) and beer, such as α-, β-, and iso-α-acids, are known to affect beer quality and display various physiological effects. However, these compounds readily oxidize, and the effect of the oxides on the properties of beer or their potential health benefits are not well understood. In this study, we developed a simple preparative method for the bitter acid oxide fraction derived from hops and designated the constituents as matured hop bitter acids (MHBA). HPLC-PDA-ESI/HRMS and MS2 revealed that MHBA are primarily composed of α-acid-derived oxides, which possess a common β-tricarbonyl moiety in their structures similar to α-, β-, and iso-α-acids. We also developed a quantitative analytical method of whole MHBA by HPLC, which showed high precision and reproducibility. Using our newly developed method, the concentration of whole MHBA in several commercial beers was evaluated. Our results will promote the study of bitter acid oxides. 相似文献
44.
Chie Urashi Kosuke M. Teshima Sumiko Minobe Osamu Koizumi Nobuyuki Inomata 《Ecology and evolution》2013,3(7):2251-2261
Inference of genetic structure and demographic history is fundamental issue in evolutionary biology. We examined the levels and patterns of genetic variation of a widespread mangrove species in the Indo‐West Pacific region, Bruguiera gymnorrhiza, using ten nuclear gene regions. Genetic variation of individual populations covering its distribution range was low, but as the entire species it was comparable to other plant species. Genetic differentiation among the investigated populations was high. They could be divided into two genetic clusters: the West and East clusters of the Malay Peninsula. Our results indicated that these two genetic clusters derived from their ancestral population whose effective size of which was much larger compared to the two extant clusters. The point estimate of speciation time between B. gymnorrhiza and Bruguiera sexangula was two times older than that of divergence time between the two clusters. Migration from the West cluster to the East cluster was much higher than the opposite direction but both estimated migration rates were low. The past Sundaland and/or the present Malay Peninsula are likely to prevent gene flow between the West and East clusters and function as a geographical or land barrier. 相似文献
45.
TGF-beta isoform signaling regulates secondary transition and mesenchymal-induced endocrine development in the embryonic mouse pancreas 总被引:1,自引:0,他引:1
Tulachan SS Tei E Hembree M Crisera C Prasadan K Koizumi M Shah S Guo P Bottinger E Gittes GK 《Developmental biology》2007,305(2):508-521
Transforming growth factor-beta (TGF-beta) superfamily signaling has been implicated in many developmental processes, including pancreatic development. Previous studies are conflicting with regard to an exact role for TGF-beta signaling in various aspects of pancreatic organogenesis. Here we have investigated the role of TGF-beta isoform signaling in embryonic pancreas differentiation and lineage selection. The TGF-beta isoform receptors (RI, RII and ALK1) were localized mainly to both the pancreatic epithelium and mesenchyme at early stages of development, but then with increasing age localized to the pancreatic islets and ducts. To determine the specific role of TGF-beta isoforms, we functionally inactivated TGF-beta signaling at different points in the signaling cascade. Disruption of TGF-beta signaling at the receptor level using mice overexpressing the dominant-negative TGF-beta type II receptor showed an increase in endocrine precursors and proliferating endocrine cells, with an abnormal accumulation of endocrine cells around the developing ducts of mid-late stage embryonic pancreas. This pattern suggested that TGF-beta isoform signaling may suppress the origination of secondary transition endocrine cells from the ducts. Secondly, TGF-beta isoform ligand inhibition with neutralizing antibody in pancreatic organ culture also led to an increase in the number of endocrine-positive cells. Thirdly, hybrid mix-and-match in vitro recombinations of transgenic pancreatic mesenchyme and wild-type epithelium also led to increased endocrine cell differentiation, but with different patterns depending on the directionality of the epithelial-mesenchymal signaling. Together these results suggest that TGF-beta signaling is important for restraining the growth and differentiation of pancreatic epithelial cells, particularly away from the endocrine lineage. Inhibition of TGF-beta signaling in the embryonic period may thus allow pancreatic epithelial cells to progress towards the endocrine lineage unchecked, particularly as part of the secondary transition of pancreatic endocrine cell development. TGF-beta RII in the ducts and islets may normally serve to downregulate the production of beta cells from embryonic ducts. 相似文献
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48.
Organotypic culture systems of functional neural tissues are important tools in neurobiological research. Ideally, such a system should be compatible with imaging techniques, genetic manipulation, and electrophysiological recording. Here we present a simple interphase tissue culture system for adult rabbit retina that requires no specialized equipment and very little maintenance. We demonstrate the dissection and incubation of rabbit retina and particle-mediated gene transfer of plasmids encoding GFP or a variety of subcellular markers into retinal ganglion cells. Rabbit retinas cultured this way can be kept alive for up to 6 days with very little changes of the overall anatomical structure or the morphology of individual ganglion- and amacrine cells. 相似文献
49.
Ayer Christopher G. Morita Kodai Fukui Sho Koizumi Itsuro 《Ichthyological Research》2022,69(2):261-266
Ichthyological Research - We evaluated the effects of a buccal cavity attaching Salmincola sp. on white-spotted charr Salvelinus leucomaenis by mark-recapture method to compare body condition,... 相似文献