Frontiers Media SA Acta Medica Okayama 2235-2988 15 2026 Binding of IgA1 and surface-expressed collagen-binding protein of Streptococcus mutans contributes to IgA nephropathy pathogenesis 1673581 EN Daiki Matsuoka Department of Pediatric Dentistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Kana Suehara Department of Pediatric Dentistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Shuhei Naka Department of Pediatric Dentistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Taro Misaki Division of Nephrology, Seirei Hamamatsu General Hospital Yasuyuki Nagasawa Department of General Internal Medicine, Hyogo Medical University Seigo Ito Department of Internal Medicine, Japan Self-Defense Force Iruma Hospital Yuto Suehiro Department of Pediatric Dentistry, Graduate School of Dentistry, The University of Osaka Ryota Nomura Department of Pediatric Dentistry, Graduate School of Biomedical and Health Sciences, Hiroshima University Kazuhiko Nakano Department of Pediatric Dentistry, Graduate School of Dentistry, The University of Osaka Michiyo Matsumoto-Nakano Department of Pediatric Dentistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Background: The present study was conducted to examine the interaction between collagen-binding protein (Cnm) of Streptococcus mutans and immunoglobulin (IgA) to clarify the possible involvement in IgA nephropathy (IgAN) development.<br> Methods: The binding of Cnm to human immunoglobulins was examined using an enzyme-linked immunosorbent assay. A nephritis-induced rat model was employed to confirm the localization of Cnm.<br> Results: IgA1 showed significantly greater binding ability to Cnm than to other bacterial surface proteins, and Cnm showed significantly greater binding ability to IgA1 than to other immunoglobulins. In rats administered Cnm, IgA deposition was observed in the glomerular mesangial region. Furthermore, biotin-labeled Cnm was observed in the same region as IgA deposition in the Cnm group.<br> Conclusions: Taken together, it is considered that following invasion into the bloodstream, Cnm binds to and forms a complex with IgA1, leading to deposition of IgA1 in renal glomeruli. No potential conflict of interest relevant to this article was reported.

Frontiers Media S.A. Acta Medica Okayama 2235-2988 12 2022 Cnm of Streptococcus mutans is important for cell surface structure and membrane permeability 994014 EN Shuhei Naka Department of Pediatric Dentistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Daiki Matsuoka Department of Pediatric Dentistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Kana Goto Department of Pediatric Dentistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Taro Misaki Division of Nephrology, Seirei Hamamatsu General Hospital Yasuyuki Nagasawa Department of General Internal Medicine, Hyogo College of Medicine Seigo Ito Department of Internal Medicine, Japan Self-Defense Iruma Hospital Ryota Nomura Department of Pediatric Dentistry, Division of Oral infection and Disease Control, Osaka University Graduate School of Dentistry Kazuhiko Nakano Department of Pediatric Dentistry, Division of Oral infection and Disease Control, Osaka University Graduate School of Dentistry Michiyo Matsumoto-Nakano Department of Pediatric Dentistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Streptococcus mutans, a Gram-positive facultative anaerobic bacterium, is a major pathogen of dental caries. The protein Cnm of S. mutans is involved in collagen binding, but its other biological functions are unknown. In this study, a Cnm-deficient isogenic mutant and a complementation strain were generated from a Cnm-positive S. mutans strain to help determine the properties of Cnm. Initially, comparison of the cell surface structure was performed by electron microscopy, which demonstrated that Cnm appears to be localized on the cell surface and associated with a protruding cell surface structure. Deep RNA sequencing of the strains revealed that the defect in Cnm caused upregulated expression of many genes related to ABC transporters and cell-surface proteins, while a few genes were downregulated. The amount of biofilm formed by the Cnm-defective strain increased compared with the parental and complemented strains, but the biofilm structure was thinner because of elevated expression of genes encoding glucan synthesis enzymes, leading to increased production of extracellular polysaccharides. Particular antibiotics, including bacitracin and chloramphenicol, had a lower minimum inhibitory concentration for the Cnm-defective strain than particular antibiotics, including bacitracin and chloramphenicol, compared with the parental and complemented strains. Our results suggest that S. mutans Cnm is located on the cell surface, gives rise to the observed protruding cell surface, and is associated with several biological properties related to membrane permeability. No potential conflict of interest relevant to this article was reported.

Japan Society for Bioscience, Biotechnology, and Agrochemistry Acta Medica Okayama 0916-8451 71 4 2007 Three antinematodal diterpenes from Euphorbia kansui 1086 1089 EN Jian-Xiao Shi Zhi-Xuan Li Teruhiko Nitoda Minoru Izumi Hiroshi Kanzaki Naomichi Baba Kazuyoshi Kawazu Shuhei Nakajima Three compounds, 20-O-acetyl-[3-O-(2'E,4'Z)-deca-dienoyl]-ingenol (1), 20-O-acetyl-[5-O-(2'E,4'Z)-decadienoyl]-ingenol (2) and 3-O-(2'E,4'Z)-decadienoylingenol (3), were isolated from Euphorbia kansui under the bioassay-guided method. Each compound showed the same antinematodal activity against the nematode, Bursaphelenchus xylophilus, at a minimum effective dose (MED) of 5 mu g/cotton ball. No potential conflict of interest relevant to this article was reported.

Japan Society for Bioscience, Biotechnology, and Agrochemistry Acta Medica Okayama 0916-8451 71 3 2007 Glucosylation of Sucrose Laurate with Cyclodextrin Glucanotransferase 826 829 EN Katsuhide Okada Haisuo Zhao Minoru Izumi Shuhei Nakajima Naomichi Baba Sucrose monolauroyl esters were found to serve as substrates for cyclodextrin glucanotransferase (CGTase)-catalyzed transglucosidation reactions, affording new sucrose esters that have an additional 1-3 glucose residues on the pyranose ring of the sucrose moiety in the ester. No potential conflict of interest relevant to this article was reported.

Japan Society for Bioscience, Biotechnology, and Agrochemistry Acta Medica Okayama 0916-8451 71 4 2007 Synthesis of lipid derivatives of pyrrole polyamide and their biological activity 1078 1082 EN Masahiko Yamamoto Changjin Zhu Lui Yi Zheng Rong Yoshie Miura Minoru Izumi Shuhei Nakajima Ken-ichi Tanamoto Sakayu Shimizu Naomichi Baba Novel fatty acyl and phospholipid derivatives of pyrrole polyamide were synthesized. Their cytotoxicity against a cancer cell line of MT-4 cells and those infected by human immunodeficiency virus (HIV) was examined. Although no anti-HIV activity was found, their cytotoxicitty against the cancer cells was significantly enhanced by introducing a lipophilic group into the pyrrole polyamide. No potential conflict of interest relevant to this article was reported.

岡山大学農学部 Acta Medica Okayama 0474-0254　 99 1 2010 Chemoenzymatic Synthesis of Phospholipid Hydroperoxides 71 84 EN Naomichi Baba Kenji Yoneda Keiji Sasakura Yasutami Shigeta Yasuhiro Kishida Akihiro Aoishi Hiroko Daido Shuhei Nakajima Junkichi Iwasa Shoichi Tahara Takao Kaneko Mitsuyoshi Matsuo Sakayu Shimizu Chemoenzymatic synthesis of 1-stearoyl-2-hydropeoxyacyl-sn-glycerophospholipids including phosphatidylcholine (PC-OOH), phosphatidic acid (PA-OOH), phosphatidylethanolamine (PE-OOH), phosphatidylglycerol (PG-OOH) and phosphatidylserine (PS-OOH). The hydroperoxy acyl moieties were prepared via hydroperoxidation of linoleic, dihomo-γ-linolenic and arachidonic acids by soybean, potate lipoxygenase or autoxidation. Their hydroperoxy group was protected as a dimethylperacetal before condensation with lysophosphatidylcholine. Optically active lysophosphatidylcholine was prepared via short pathway involving lipase-catalyzed direct enantioselective stearoylation of 2-O-benzylglycerol and choline phosphate synthesis. Peroxy fatty acids and lysophosphatidylcholine thus obtained were condensed using dicyclohexylcarbodiimide in chloroform. Removing the peracetal group in the product and purification by reverse-phase chromatography afforded the desired PC-OOH’s. PA-OOH, PG-OOH, PE-OOH and PS-OOH were obtained by phospholipase-D catalyzed transphosphatidylation from PC-OOH. As a reference compound for biological studies of hydroperoxy phopholipid, PC-OH's were also prepared in which hydroxy unsaturated fatty acyl group was linked to the sn-2 position of the glycerophospholipids. No potential conflict of interest relevant to this article was reported.

岡山大学農学部 Acta Medica Okayama 0474-0254 84 1 1995 Plant Growth Regulators from Kenyan Plant, Psiadia punctulata 7 11 EN Joseph Mungai Keriko Shuhei Nakajima Naomichi Baba Yumika Isozaki Junkichi Iwasa Compounds having plant growth regulatory effect were found in Kenyan Psiadia punctulata, and two flavones,5-hydroxy-7,2',3',4',5'-pentamethoxyflavone(1) and 5,3'-dihydroxy-7,2',4',5'-tetramethoxyflavone(2) were isolated and identified as the activ constituents. No potential conflict of interest relevant to this article was reported.

岡山大学農学部 Acta Medica Okayama 0474-0254 86 1 1997 Preventive Action of Vegetables on Degradation of Methyl 13-Hydroperoxyoctadecadienoate 21 25 EN Md Khorshed Alam Rumiko Shimizu Eiko Yamada Naomichi Baba Shuhei Nakajima The preventive actions of some vegetables on the degradation of 13-hydroperocxyoctadecadienoate were investigated.Among these,kindly bean extract prevented the degradation of the hydroperoxide at about 60% followed by green pepper,cucumber,spinach pumpkin,mushroom,carrot,and shungiku to defferent degrees. No potential conflict of interest relevant to this article was reported.

岡山大学農学部 Acta Medica Okayama 0474-0254 86 1 1997 Ketosteroids As Arrestants to Oryzaephilus surinamensis (L.) from Wheat Flour Infested by the Same Weevil 7 11 EN Shuhei Nakajima Akiko Okamoto Keiji Sugawara Taro Takeda Junkichi Iwasa Naomichi Baba From hexane extract of wheat flour infested by the sawtoothed gain beetle [Oryzaephilus surinamensis (L.); Coleoptera; Silvanidae, three ketosteroids,cholestan-3-one(3),ergostan-3-one(4)and stigmastan-3-one(5),were obtained in a mixture and identified as arrestants to this weevil. No potential conflict of interest relevant to this article was reported.

岡山大学農学部 Acta Medica Okayama 0474-0254 87 1 1998 Lipase Activity for Lipid Hydroperoxides 65 69 EN Naomichi Baba Naohisa Hirota Shuhei Nakajima Catalytic activity of lipase P (Amano) from pseudomonas fluorescens for lipid hydroperoxides were examined and in organic solvent the enzyme was found to catalyze acylation reaction of the hydroperoxy group in a stereoselective manner producing optically active hydroperoxy compounds, whereas in aqueous medium the lipase-catalyzed ester hydrolysis afforded a complicated mixture of unknown reaction products. No potential conflict of interest relevant to this article was reported.

岡山大学農学部 Acta Medica Okayama 0474-0254 87 1 1998 Biologically Active Substance from Kenyan Plant, Vernonia hindii S. Moore (Asteraceae) 17 21 EN Glaston Mwangi Kenji Shuhei Nakajima Naomichi Baba Junkichi Iwasa A novel stigmastane-type steroid glucoside glucoside has been isolated from the aerial parts of Vernonia hindii.The structure was elucidated by spectroscopic methods.The compound exhibitewd lettuce seedling growth inhibitory activity. No potential conflict of interest relevant to this article was reported.

岡山大学農学部 Acta Medica Okayama 0474-0254 87 1 1998 バリダマイシン生産菌が生成する揮発物質 23 27 EN Eiji Higashide Toshinari Ohashi Mohamada Mahfuzul Hoque shuhei Najima Streptomyces hygroscopicus subsp. limoneus JCM 4911 , a validamycin producer was found to produce a volatile in the validamycin producing medium . The volatile was produced only by the organism which could form abundant aerial mycelium during the growth phase for one to two days of the culture and, thereafter, it decreased. Maximum production (3.88μg/ml) of the volatile was found in two-days' cultured broth with the conditions for validamycin production. On the contrary, the validamycin production started at around two days into the culture and increased up to five to seven days of the culture with maximum production of 440μg/ml. The volatile was extracted with n-pentane from the culture broth of S. hygroscopicus subsp. limoneus JCM 4911 and was identical with n-hexanol by GC-MS analysis. No potential conflict of interest relevant to this article was reported.

岡山大学農学部 Acta Medica Okayama 0474-0254 88 1 1999 バリダマイシン生成菌培養液から抗細菌性抗生物質ノカルダミンの分離・精製 13 17 EN Eiji Higashide Yoshiharu Omatsu Suemi Inoue Yoshinobu Kimura Hiroshi Kanzaki Shuhei Nakajima An antibacterial active against P. mirabilis was isolated from the culture of Streptomyces hygroscopicus subsp. limoneus, validamycin producer. The antibiotic was found to be produced with a non-validamycin producing condition. The antibiotic was identified as nocardamine with the analytical data, IR, 1H-NMR and 13C-NMR spectra. No potential conflict of interest relevant to this article was reported.

岡山大学農学部 Acta Medica Okayama 0474-0254 90 1 2001 Stereochemical Determination of 2-0-Methoxyethoxymethylglycerol Bearing Polyunsaturated Fatty Acyl Group at sn-1 Position 5 8 EN Kotaro Matsumoto Yoshihiro Mori Shuhei Nakajima Naomichi Baba Sakayu Shimizu A correlation of optical rotation, optical purity and configuration of the asymmetric center was done for 2-0-methoxyethoxymethylglycerol bearing polyunsaturated fatty acyl group at sn-1 position. This compound was enzymatically prepared and is an important starting material for the syntheses of optical active glycerophospholipids naving polyunwaturated fatty acyl groups. No potential conflict of interest relevant to this article was reported.

岡山大学農学部 Acta Medica Okayama 0474-0254 90 1 2001 Synthesis of Carbon Analogues of Phosphatidylcholines Having a Polyunsaturated Fatty Acid at the 2-Position 1 4 EN Chiyo Seki Yoshihiro Mori Shuhei Nakajima Sakayu Shimizu Naomichi Baba Carbon analogues of Phosphatidylcholines having linoleic or arachidonic acid at the 2-position were synthesized. The synthetic route involves conversion of the polyunsaturated fatty acid iodination. The derivatives were converted to diols by LiAIH4 reduction and submitted to lipase-catalyzed monostearoylation in isopropylether. The mono-ester was converted to phoshatidylcholines by the usual phosphodiester synthesis. No potential conflict of interest relevant to this article was reported.

岡山大学農学部 Acta Medica Okayama 0474-0254 92 1 2003 β-SitosteryI-D-glucoside from the Olive Tree(Olea europaea LINNE; Oleaceae) as a Feeding Stimulant toward the Olive Weevil (Dyscerus perforatus) 1 4 EN Emiko Kadowaki Yasuhiro Yoshida Naomichi Baba Shuhei Nakajima The olive weevil [Dyscerus perforatus (ROELOFS); Coleopetera; Curculionidae] is a native species in Japan and now the most serious pest of the olive trees. Originally, this weevil seemed to colonise Ligustrum japonicum Thumb. and L. obtusifolium Sieb. et Zucc, both of which belong to the same oleacea family as olive. However, when olive trees were introduced to Japan in 1908, the weevils immediately attacked the plants and soon preferred them to the former hosts. Unlike in the former hosts, where the weevils live in a low population density, it is extraordinary high in the case of olive trees and the subsequent assault becomes seriously damaging for the host plant. During the course of our study on the relationship between olive trees and olive weevils, we came to be interested in the possible chemical constituents that are responsible for host selection and attraction of the olive weevil to this plant. Previously, we reported that a secoiridoid gluconside, oleuropein, and some lignans, (-)-olivil and (+)-l-acetoxypinoresinol, from the olive tree stimulated the feeding habit of the weevil. In this study, we found a steroidal glucoside as another feeding stimulant component in the olive tree. Here, we describe the isolation, characterization and activity of this feeding stimulant. No potential conflict of interest relevant to this article was reported.

岡山大学農学部 Acta Medica Okayama 0474-0254 93 1 2004 Ageratum conyzoidesに含まれる殺線虫活性物質 1 4 EN Shuhei Nakajima Kazuto Takaishi Youichi Nagano Yohannes Alen Kazuyoshi Kawazu Naomichi Baba Activity-guided chromatographic purification of the methanol extract of Ageratum conyzoides, using pine wood nematodes Bursaphelenchus xylophilus successfully led to the isolation and characterization of the nematicidal compound with minimum effective dose (MED) of 75 μg/ cotton ball (μg/bl.). Based on the chemical and spectral properties, the compound was determined to be coumarin (1). The activity of coumarin derivatives (2-5) was also investigated. No potential conflict of interest relevant to this article was reported.

岡山大学農学部 Acta Medica Okayama 0474-0254 79 1 1992 Introduction of Several Groups to the D-ring of Grayanotoxin 1 35 EN Junkichi Iwasa Tetsuroh Kawanishi Satoshi Handa Hideki Kamano Shingo Yamamoto Manabu Okamoto Norimasa Takeda Mikihiko Nakamura Tetsuya Masutani Motoo Shiro Shuhei Nakajima Naomichi Baba Issei Seyama Grayanotoxin (GTX), one of the lipid-soluble Na+ channel openers, contains four rings (A, B, C and D) and the chemical groups essential for the pharmacological action are located on the A- and B-rings. To study the biological significance of functional groups on the D-ring, 51 new derivatives were prepared from α-dihydro GTX- 11 . These new compounds and the previously prepared GTXS ere directly applied to the intracellular phase of internally perfused squid giant axons. No potential conflict of interest relevant to this article was reported.