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The influence of sodium fluoride (NaF) on calcium metabolism was examined in nibbler fish (marine teleosts). Two days after the administration of NaF (5 μg/g of body weight) (around 10−4 M in fish), we showed that plasma calcium levels significantly decreased in NaF-treated nibbler fish. In addition, we detected fluoride in the treated scales by use of a scanning electron microscope with an energy-dispersive X-ray microanalysis, indicating that NaF directly affects their scales. Therefore, the influence of NaF on osteoblasts and osteoclasts in the scales was examined. In the scales of NaF-injected nibbler fish, tartrate-resistant acid phosphatase (TRAP) (osteoclastic marker enzyme) decreased, although alkaline phosphatase (osteoblastic marker enzyme) was activated. To confirm the effect of NaF on osteoclasts, furthermore, the mRNA expressions of osteoclastic markers (matrix metalloproteinase-9 and TRAP) were decreased significantly 2 days after incubation. In barred knifejaws, plasma calcium levels decreased as they did in nibbler fish. Therefore, NaF functions in both osteoblasts and osteoclasts and then influences calcium metabolism in marine fish. In the marine environment, high levels of fluoride (1.2–1.5 mg F−/l) (around 10−5–10−4 M) are present in seawater. It is probable that teleosts living in seawater efficiently use fluoride to regulate their blood calcium levels. © 2017 Japanese Society of Fisheries Science, 出版者照会後に全文公開 / Embargo Period 12 months, Erratum to: Sodium fluoride influences calcium metabolism resulting from the suppression of osteoclasts in the scales of nibbler fish Girella punctata (Fish Sci, 10.1007/s12562-017-1086-0)( https://link.springer.com/article/10.1007%2Fs12562-017-1092-2

本報告では，苗木生産に使用できる胎生種子の状態を明らかにすることを目的として，メヒルギ（Kandelia candel）胎生種子の大きさの違いおよび根原基形成が植栽後の発根や根およびシュートの伸長成長量の大きさにおよぼす効果について検討した。その結果，発根に必要な根原基は長さ 2 cm以上の胎生種子で確認された。また，胎生種子が大きくなるほど根原基数は増加し，根原基の長さや幅も増大した。さらに，胎生種子が大きくなるほど，発根本数は増加し，根およびシュートの伸長成長量も増加した。これらの現象は一般的な植物の種子の発芽および発根と類似していた。しかし，長さ 6 cm未満の胎生種子は生育過程で枯死した。これらを基に，長さ 8 cm以上の胎生種子では100％の発根率を示すことから，メヒルギの苗木生産に使用できるものと考えられる。

The atmospheric epiphyte Tillandsia ionantha is capable of surviving drought stress for 6 months or more without any exogenous water supply via an as of yet to be determined mechanism. When plants were soaked in water for 3 h, leaves absorbed a remarkably large amount of water (30-40% on the basis of fresh weight), exhibiting a bimodal absorption pattern. Radiolabeled water was taken up by the leaves by capillary action of the epidermal trichomes within 1 min (phase 1) and then transported intracellularly to leaf tissues over 3 h (phase 2). The removal of epidermal trichome wings from leaves as well as rinsing leaves with water significantly lowered the extracellular accumulation of water on leaf surfaces. The intracellular transport of water was inhibited by mercuric chloride, implicating the involvement of a water channel aquaporin in second-phase water absorption. Four cDNA clones (TiPIP1a, TiPIP1b, TiPIP1c, and TiPIP2a) homologous to PIP family aquaporins were isolated from the leaves, and RT-PCR showed that soaking plants in water stimulated the expression of TiPIP2a mRNA, suggesting the reinforcement in ability to rapidly absorb a large amount of water. The expression of TiPIP2a complementary RNA in Xenopus oocytes enhanced permeability, and treatment with inhibitors suggested that the water channel activity of TiPIP2a protein was regulated by phosphorylation. Thus, the high water uptake capability of T. ionantha leaves surviving drought is attributable to a bimodal trichome- and aquaporin-aided water uptake system based on rapid physical collection of water and subsequent, sustained chemical absorption.

分画分子量20万の限外ろ過膜により，仙草多糖類を分画，洗浄を繰り返すことで，破断強度や弾性率および粘性率が増加することが認められ，より粘性のある硬いゲルが形成された．また電子顕微鏡によるゲル組織の観察によると，タピオカデンプンのみで作成したゲルの持つ網目構造と比較すると，HTPで作成したゲルはより細かな網目構造が全体に広がっていた．また，限外濾過による処理数を増加することにより，部分的に密な状態である組織が観察された．先ほど述べた，限外濾過による処理を繰り返すことによりゲルが強化されることと，ゲル組織が部分的に密な状態になることと相関関係があると考えられた．

マングローブ林を構成する木本植物の効率の良い造林を行うための苗木の大量生産を目的とした基礎的研究として，メヒルギ胎生種子の植え付け深さの違いによる発根現象を調査した。その結果，胎生種子のシュート伸長成長は深く植え付けるほど促進効果がみられ，サンゴジュやモモなどの他の樹種のさし木の発根におけるこれまでの報告と同様の結果が得られた。植え付け前に根源体の形成がみられた下部発根は，植え付け深さの違いによって下部根の発根部位や発根本数には違いがみられなかった。しかし，植え付け後に根源体の形成された上部発根は，深く植え付けたものほど発根部位が拡大し発根本数も増加した。これらのことから，メヒルギ胎生種子の上部発根は，植え付けたことによる培地との接触が刺激となって根源体が形成されたと考えられる。また，上部発根と下部発根との間には約 2 cmの無発根の部位がみられた。

Imprinted genes have prominent effects on placentation; however, there is limited knowledge about the manner in which the genes controlled by two paternally methylated regions on chromosomes 7 and 12 contribute to placentation. In order to clarify the functions of these genes in mouse placentation, we examined transcription levels of the paternally methylated genes, tissue differentiation and development and the circulatory system in placentae derived from three types of bi-maternal conceptuses that contained genomes of non-growing (ng) and fully grown (fg) oocytes. The genetic backgrounds of the ng oocytes were as follows: one was derived from the wild-type (ngWT) and another from mutant mice carrying a 13 kb deletion in the H19 transcription unit including the germline-derived differentially methylated region (H19-DMR) on chromosome 7 (ngDeltach7). Another set of oocytes was derived from mutant mice carrying a 4.15 kb deletion in the intergenic germline-derived DMR (IG-DMR) on chromosome 12 (ngDeltach12). Although placental mass was lower in the ngWT/fg placentae compared with that in the WT placentae, it was recovered in the ngDeltach7/fg placentae, but not in the ngDeltach12/fg placentae. The ngDeltach7/fg placental growth improvement was associated with severe dysplasia such as an expanded spongiotrophoblast layer and a malformed labyrinthine zone. In contrast, the ngDeltach12/fg placentae retained the layer structures with expanded giant cells, but their total masses were smaller with a normal circulatory system in order. Our findings demonstrate that the genes controlled by the two paternally methylated regions, H19-DMR and IG-DMR, complementarily organize placentation.

Anthracnose of Japanese radish found in Kagoshima and Miyazaki prefectures was demonstrated to be caused by Colletotrichum dematium based on inoculation experiments and morphological and molecular identification of the pathogenic fungus. Although symptoms of Japanese radish anthracnose caused by Colletotrichum higginsianum were similar to those caused by C. dematium, damage by the latter pathogen was more severe than that by C. higginsianum.

The influence of sodium fluoride (NaF) on calcium metabolism was examined in nibbler fish (marine teleosts). Two days after the administration of NaF (5 μg/g of body weight) (around 10−4 M in fish), we showed that plasma calcium levels significantly decreased in NaF-treated nibbler fish. In addition, we detected fluoride in the treated scales by use of a scanning electron microscope with an energy-dispersive X-ray microanalysis, indicating that NaF directly affects their scales. Therefore, the influence of NaF on osteoblasts and osteoclasts in the scales was examined. In the scales of NaF-injected nibbler fish, tartrate-resistant acid phosphatase (TRAP) (osteoclastic marker enzyme) decreased, although alkaline phosphatase (osteoblastic marker enzyme) was activated. To confirm the effect of NaF on osteoclasts, furthermore, the mRNA expressions of osteoclastic markers (matrix metalloproteinase-9 and TRAP) were decreased significantly 2 days after incubation. In barred knifejaws, plasma calcium levels decreased as they did in nibbler fish. Therefore, NaF functions in both osteoblasts and osteoclasts and then influences calcium metabolism in marine fish. In the marine environment, high levels of fluoride (1.2–1.5 mg F−/l) (around 10−5–10−4 M) are present in seawater. It is probable that teleosts living in seawater efficiently use fluoride to regulate their blood calcium levels.

Ramicandelaber, a new genus of Zygomycetes is erected to accommodateRamicandelaber longisporus sp. nov. The fungus has hyphal septa with median plugs and forms homologous structures to sporocladia and pseudophialides. These characteristics suggest that it belongs to the Kickxellales, Zygomycetes.

In 1992, diseased flowers of cosmos (Cosmos bipinnatus) were found in Kanagawa Prefecture, Japan. Small water-soaked lesions occurred first on flowers and flower buds. These lesions then enlarged and turned light brown. Diseased flowers and flower buds eventually fell off. The fungus produced fusiform conidia on the PDA medium, 11-14×2.8-3.5μm in size. From those results, the fungus was identified as Colletotrichum acutatum Simmonds ex Simmonds. It has been newly added as a pathogen causing anthracnose on cosmos.

輸入パパイアの腐敗を1986年から1987年に調査した結果,わが国では未報告の軸部の腐敗が認められた。その病徴は5タイプに類別され,病原菌の形態的特徴および接種試験の結果,パパイアの軸部の腐敗に関与する病原菌としてBotryodiplodia theobromae, Phomopsis sp., Colletotrichum gloeosporioides, Fusarium solani, Ascochyta caricaeを同定した。この病名をパパイア軸腐病(stem-end rot)と呼称することを提案した。

The effects on rabbit tissue-cultured cells of collagenolytic cell wall component (CCWC) from Fusobacterium necrophorum subsp. necrophorum were investigated. Scanning electron microscopy demonstrated that CCWC damaged the cell surfaces of the rabbit granulocytes and hepatocytes but the effects of the cells differed from each other. Granulocytes appeared smooth and morphologically irregular whereas hepatocytes looked rough and had tiny holes in the cell membranes. Differences in cell viability were observed in MTS (3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulphophenyl)-2H-tetrazolium, inner salt) assay. The findings suggest that cytotoxic activity in vivo may well contribute to the establishment of an initial injury in visceral tissues, and the action of CCWC could increase the chances of survival for an invading F. necrophorum subsp. necrophorum at the first stages of infection.

1998年,沖縄県豊見城村で収穫前のグアバ果実に腐敗が発生した。最初,緑色の果実表面に褐色小斑が発生,その後成熟した黄色の果実に茶褐色の病斑が急速に拡大し,果実表皮下に未熟な分生子層が多数形成され,さらに表皮を裂開した成熟分生子層からは円筒形の分生子(大きさ : 8.1～18.8μm×3.5～4.5μm)が豊富に観察された。また得られた分離株を用い接種試験を行った結果,グアバをはじめパパイア,マンゴー果実にも病原性を示した。これらの結果から本病は,Colletotrichum gloeosporioides (Penzig) Penzig & Saccardoによって引き起こされた炭疽病であることが確認された。, In 1998, a new disease was found on Guava (Psidium guajava L.) fruits, in Okinawa prefecture, Japan. Small brown spot lesions appeared first on immature green fruits. After the maturation of fruits, dark brown lesion enlarged and developed rapidly on the yellow colored fruits, and bore members of concentrically arranged acervuli with orange conidial masses. A fungus was isolated from these lesions, the acervuli were subepidermal, 80～200μm in diameter and lacked setae. Conidia were aseptate, hyaline, cylindrical, apex obtuse, base truncate, and measured 8.1～18.8×3.5～4.5μm (av. 11.3×4.1μm). Appressoria were clavate or slightly irregular and brown colored and 4.7×6.8μm in size. The causal fungus was identified as Colletotrichum gloeosporioides (Penzig) Penzig & Saccardo. Anthracnose of Guava was proposed as a new disease in Japan.