76 results on '"Iwataki M"'
Search Results
2. Electronic structure of Mott-insulator CaCu3Ti4O12: Photoemission and inverse photoemission study
- Author
-
Im, H. J., Iwataki, M., Yamazaki, S., Usui, T., Adachi, S., Tsunekawa, M., Watanabe, T., Takegahara, K., Kimura, S., Matsunami, M., Sato, H., Namatame, H., and Taniguchi, M.
- Subjects
Condensed Matter - Strongly Correlated Electrons - Abstract
We have performed the photoemission and inverse photoemission experiments to elucidate the origin of Mott insulating states in A-site ordered perovskite CaCu$_3$Ti$_4$O$_{12}$ (CCTO). Experimental results have revealed that Cu 3$d$-O 2$p$ hybridized bands, which are located around the Fermi level in the prediction of the local-density approximation (LDA) band calculations, are actually separated into the upper Hubbard band at $\sim$ 1.5 eV and the lower Hubbard band at $\sim$ $-$1.7 eV with a band gap of $\sim$ 1.5-1.8 eV. We also observed that Cu 3$d$ peak at $\sim$ $-$3.8 eV and Ti 3$d$ peak at $\sim$ 3.8 eV are further away from each other than as indicated in the LDA calculations. In addition, it is found that the multiplet strucutre around $-$9 eV includes a considerable number of O 2$p$ states. These observations indicate that the Cu 3$d$ and Ti 3$d$ electrons hybridized with the O 2$p$ states are strongly correlated, which originates in the Mott-insulating states of CCTO., Comment: 11 pages, 3 figures
- Published
- 2015
- Full Text
- View/download PDF
3. Strong Correlation Effects of A-site Ordered Perovskite CaCu3Ti4O12 revealed by Angle-Resolved Photoemission Spectroscopy
- Author
-
Im, H. J., Tsunekawa, M., Sakurada, T., Iwataki, M., Kawata, K., Watanabe, T., Takegahara, K., Miyazaki, H., Matsunami, M., Hajiri, T., and Kimura, S.
- Subjects
Condensed Matter - Strongly Correlated Electrons - Abstract
We report angle-resolved photoemission spectroscopy (ARPES) results of A-site ordered perovskite CaCu$_3$Ti$_4$O$_{12}$. We have observed the clear band dispersions, which are shifted to the higher energy by 1.7 eV and show the band narrowing around 2 eV in comparison with the local density approximation calculations. In addition, the high energy multiplet structures of Cu 3$d^8$ final-states have been found around 8 - 13 eV. These results reveal that CaCu$_3$Ti$_4$O$_{12}$ is a Mott-type insulator caused by the strong correlation effects of the Cu 3$d$ electrons well hybridized with O 2$p$ states. Unexpectedly, there exist a very small spectral weight at the Fermi level in the insulator phase, indicating the existence of isolated metallic states., Comment: 5 pages, 5 figures
- Published
- 2013
- Full Text
- View/download PDF
4. Fish-Killing Marine Algal Blooms: Causative Organisms, Ichthyotoxic Mechanisms, Impacts and Mitigation.
- Author
-
Hallegraeff, G.M., Anderson, D. M., Davidson, K., Gianella, F., Hansen, P. J., Hegaret, H., Iwataki, M., Larsen, T. O., Mardones, J., MacKenzie, L., Rensel, J.E., Hallegraeff, G.M., Anderson, D. M., Davidson, K., Gianella, F., Hansen, P. J., Hegaret, H., Iwataki, M., Larsen, T. O., Mardones, J., MacKenzie, L., and Rensel, J.E.
- Abstract
Fish-killing microalgal blooms are responsible for much greater global socio-economic impacts than the well-studied HAB species causing seafood biotoxin contamination. Examples are the 1972 Chattonella marina bloom in the Seto Inland Sea, Japan (estimated USD 71M loss to yellowtail aquaculture), the 1988 Prymnesium polylepis bloom in the European Kattegat with broad marine ecosystem impacts, and the 2015/16 Pseudochattonella verruculosa bloom in Chile (USD 800M loss to salmon aquaculture). Highly potent fish-killers include the globally distributed, taxonomically unrelated dinoflagellate genera Alexandrium, Karenia, Karlodinium and Margalefidinium, raphidophytes Chattonella and Heterosigma, dictyochophytes Pseudochattonella and Vicicitus, and haptophytes Chrysochromulina and Prymnesium. All these species have in common their propensity to produce lytic compounds that irreparably damage the sensitive gill tissues of fish which ultimately die from suffocation. Except for recent advances with Karlodinium (karlotoxins), Prymnesium (prymnesins), and Karenia brevisulcata (brevisulcenals), the precise mechanisms of how such microalgae kill finfish remain poorly understood. Reactive Oxygen Species can be a co-factor in ichthyotoxicity, notably with raphidophytes such as Chattonella. While some species are always ichthyotoxic, others such as Heterosigma, Pseudochattonella and Alexandrium catenella kill fish only under certain conditions or life stages. Broad scale ecosystem impacts from fish killing algae are less common with raphidophytes and dictyochophytes that require intimate cellular contact for harmful effects, compared to Karenia and Prymnesium where intracellular or excreted toxins are responsible. Critical hurdles that limit progress in our understanding of ichthyotoxins and their control and mitigat
- Published
- 2023
5. Morphological and phylogenetic data do not support the split of Alexandrium into four genera
- Author
-
Mertens, Kenneth Neil, Adachi, M., Anderson, Donald M., Band-Schmidt, Christine J., Bravo, I., Brosnahan, Michael L., Bolch, Christopher, Calado, A.L., Carbonell-Moore, M.C., Chomérat, Nicolas, Elbrächter, Malte, Figueroa, R.I., Fraga, Santiago, Gárate-Lizárraga, I., Garcés, E., Gu, Haifeng, Hallegraeff, Gustaaf, Hess, Philipp, Hoppenrath, Mona, Horiguchi, T., Iwataki, M., John, Uwe, Kremp, Anke, Larsen, Jacob, Leaw, Chui Pin, Li, Zhun, Lim, Po Teen, Litaker, Wayne, MacKenzie, Lincoln, Masseret, Estelle, Matsuoka, K., Moestrup, Øjvind, Montresor, Marina, Nagai, Satoshi, Nézan, Elisabeth, Nishimura, T., Okolodkov, Yuri, Orlova, T. Y., Rene, Albert, Sampedro, Nagore, Satta, C.T., Shin, H.H., Siano, Raffalele, Smith, Kirsty F., Steidinger, Karen, Takano, Yoshihito, Tillmann, Urban, Wolny, Jennifer, Yamaguchi, Aika, Murray, Shauna A., Mertens, Kenneth Neil, Adachi, M., Anderson, Donald M., Band-Schmidt, Christine J., Bravo, I., Brosnahan, Michael L., Bolch, Christopher, Calado, A.L., Carbonell-Moore, M.C., Chomérat, Nicolas, Elbrächter, Malte, Figueroa, R.I., Fraga, Santiago, Gárate-Lizárraga, I., Garcés, E., Gu, Haifeng, Hallegraeff, Gustaaf, Hess, Philipp, Hoppenrath, Mona, Horiguchi, T., Iwataki, M., John, Uwe, Kremp, Anke, Larsen, Jacob, Leaw, Chui Pin, Li, Zhun, Lim, Po Teen, Litaker, Wayne, MacKenzie, Lincoln, Masseret, Estelle, Matsuoka, K., Moestrup, Øjvind, Montresor, Marina, Nagai, Satoshi, Nézan, Elisabeth, Nishimura, T., Okolodkov, Yuri, Orlova, T. Y., Rene, Albert, Sampedro, Nagore, Satta, C.T., Shin, H.H., Siano, Raffalele, Smith, Kirsty F., Steidinger, Karen, Takano, Yoshihito, Tillmann, Urban, Wolny, Jennifer, Yamaguchi, Aika, and Murray, Shauna A.
- Abstract
A recently published study analyzed the phylogenetic relationship between the genera Centrodinium and Alexandrium, confirming an earlier publication showing the genus Alexandrium as paraphyletic. This most recent manuscript retained the genus Alexandrium, introduced a new genus Episemicolon, resurrected two genera, Gessnerium and Protogonyaulax, and stated that: “The polyphyly [sic] of Alexandrium is solved with the split into four genera”. However, these reintroduced taxa were not based on monophyletic groups. Therefore this work, if accepted, would result in replacing a single paraphyletic taxon with several non-monophyletic ones. The morphological data presented for genus characterization also do not convincingly support taxa delimitations. The combination of weak molecular phylogenetics and the lack of diagnostic traits (i.e., autapomorphies) render the applicability of the concept of limited use. The proposal to split the genus Alexandrium on the basis of our current knowledge is rejected herein. The aim here is not to present an alternative analysis and revision, but to maintain Alexandrium. A better constructed and more phylogenetically accurate revision can and should wait until more complete evidence becomes available and there is a strong reason to revise the genus Alexandrium. The reasons are explained in detail by a review of the available molecular and morphological data for species of the genera Alexandrium and Centrodinium. In addition, cyst morphology and chemotaxonomy are discussed, and the need for integrative taxonomy is highlighted.
- Published
- 2020
6. Morphological and phylogenetic data do not support the split of Alexandrium into four genera.
- Author
-
Mertens, KN, Adachi, M, Anderson, DM, Band-Schmidt, CJ, Bravo, I, Brosnahan, ML, Bolch, CJS, Calado, AJ, Carbonell-Moore, MC, Chomérat, N, Elbrächter, M, Figueroa, RI, Fraga, S, Gárate-Lizárraga, I, Garcés, E, Gu, H, Hallegraeff, G, Hess, P, Hoppenrath, M, Horiguchi, T, Iwataki, M, John, U, Kremp, A, Larsen, J, Leaw, CP, Li, Z, Lim, PT, Litaker, W, MacKenzie, L, Masseret, E, Matsuoka, K, Moestrup Ø, Montresor, M, Nagai, S, Nézan, E, Nishimura, T, Okolodkov, YB, Orlova, TY, Reñé, A, Sampedro, N, Satta, CT, Shin, HH, Siano, R, Smith, KF, Steidinger, K, Takano, Y, Tillmann, U, Wolny, J, Yamaguchi, A, Murray, S, Mertens, KN, Adachi, M, Anderson, DM, Band-Schmidt, CJ, Bravo, I, Brosnahan, ML, Bolch, CJS, Calado, AJ, Carbonell-Moore, MC, Chomérat, N, Elbrächter, M, Figueroa, RI, Fraga, S, Gárate-Lizárraga, I, Garcés, E, Gu, H, Hallegraeff, G, Hess, P, Hoppenrath, M, Horiguchi, T, Iwataki, M, John, U, Kremp, A, Larsen, J, Leaw, CP, Li, Z, Lim, PT, Litaker, W, MacKenzie, L, Masseret, E, Matsuoka, K, Moestrup Ø, Montresor, M, Nagai, S, Nézan, E, Nishimura, T, Okolodkov, YB, Orlova, TY, Reñé, A, Sampedro, N, Satta, CT, Shin, HH, Siano, R, Smith, KF, Steidinger, K, Takano, Y, Tillmann, U, Wolny, J, Yamaguchi, A, and Murray, S
- Abstract
A recently published study analyzed the phylogenetic relationship between the genera Centrodinium and Alexandrium, confirming an earlier publication showing the genus Alexandrium as paraphyletic. This most recent manuscript retained the genus Alexandrium, introduced a new genus Episemicolon, resurrected two genera, Gessnerium and Protogonyaulax, and stated that: "The polyphyly [sic] of Alexandrium is solved with the split into four genera". However, these reintroduced taxa were not based on monophyletic groups. Therefore this work, if accepted, would result in replacing a single paraphyletic taxon with several non-monophyletic ones. The morphological data presented for genus characterization also do not convincingly support taxa delimitations. The combination of weak molecular phylogenetics and the lack of diagnostic traits (i.e., autapomorphies) render the applicability of the concept of limited use. The proposal to split the genus Alexandrium on the basis of our current knowledge is rejected herein. The aim here is not to present an alternative analysis and revision, but to maintain Alexandrium. A better constructed and more phylogenetically accurate revision can and should wait until more complete evidence becomes available and there is a strong reason to revise the genus Alexandrium. The reasons are explained in detail by a review of the available molecular and morphological data for species of the genera Alexandrium and Centrodinium. In addition, cyst morphology and chemotaxonomy are discussed, and the need for integrative taxonomy is highlighted.
- Published
- 2020
7. P806Aortic root remodeling in patients with aortic stenosis assessed by real-time 3D transesophageal echocardiography
- Author
-
Takeuchi, M, Kaku, K, Otani, K, Iwataki, M, Kuwaki, H, Haruki, N, Yoshitani, H, and Otsuji, Y
- Published
- 2011
8. (111) Vertical-type 2DHG Diamond MOSFETs with Hexagonal Trench Structures
- Author
-
Nishimura, J., primary, Iwataki, M., additional, Oi, N., additional, Morishita, A., additional, Hiraiwa, A., additional, and Kawarada, H., additional
- Published
- 2019
- Full Text
- View/download PDF
9. Vertical-Type 2DHG Diamond MOSFETs with a Few Micro Meter Length Trench Structure
- Author
-
Iwataki, M., primary, Oi, N., additional, Horikawa, K., additional, Amano, S., additional, Kageura, T., additional, Inaba, M., additional, Hiraiwa, A., additional, and Kawarada, H., additional
- Published
- 2018
- Full Text
- View/download PDF
10. P1763Prognostic impact of right ventricular ejection fraction assessed by 3D speckle-tracking echocardiography in patients with dilated cardiomyopathy and ischemic cardiomyopathy
- Author
-
Nagata, Y, primary, Nabeshima, Y, additional, Hei, S, additional, Onoue, T, additional, Iwataki, M, additional, Otani, K, additional, Otsuji, Y, additional, and Takeuchi, M, additional
- Published
- 2018
- Full Text
- View/download PDF
11. Electronic structure of Mott-insulator CaCu 3 Ti 4 O 12 : Photoemission and inverse photoemission study
- Author
-
Im, H.J., primary, Iwataki, M., additional, Yamazaki, S., additional, Usui, T., additional, Adachi, S., additional, Tsunekawa, M., additional, Watanabe, T., additional, Takegahara, K., additional, Kimura, S., additional, Matsunami, M., additional, Sato, H., additional, Namatame, H., additional, and Taniguchi, M., additional
- Published
- 2015
- Full Text
- View/download PDF
12. Strong correlation effects in theA-site ordered perovskite CaCu3Ti4O12revealed by angle-resolved photoemission spectroscopy
- Author
-
Im, H. J., primary, Tsunekawa, M., additional, Sakurada, T., additional, Iwataki, M., additional, Kawata, K., additional, Watanabe, T., additional, Takegahara, K., additional, Miyazaki, H., additional, Matsunami, M., additional, Hajiri, T., additional, and Kimura, S., additional
- Published
- 2013
- Full Text
- View/download PDF
13. Prognostic value of left atrial volumes assessed by 3D echocardiography
- Author
-
Wu, V. C., primary, Takeuchi, M., additional, Kuwaki, H., additional, Iwataki, M., additional, Otani, K., additional, Haruki, N., additional, Yoshitani, H., additional, Lin, F. C., additional, and Otsuji, Y., additional
- Published
- 2013
- Full Text
- View/download PDF
14. Investigations of body scales in twelve Heterocapsa species (Peridiniales, Dinophyceae), including a new species H. pseudotriquetra sp. nov.
- Author
-
Iwataki, M., Hansen, Gert, Sawaguchi, T., Hiroishi, S., Fukuyo, Y., Iwataki, M., Hansen, Gert, Sawaguchi, T., Hiroishi, S., and Fukuyo, Y.
- Abstract
Udgivelsesdato: July 2004, The body scales of 12 Heterocapsa species including a new species, H. pseudotriquetra Iwataki, Gert Hansen & Fukuyo, sp. nov. were investigated by transmission electron microscopy to clarify ultrastructural differences. All species had scales with a body-scale structure consisting of a triradiate basal plate and a three-dimensional construction composed of vertically standing uprights or spines and horizontal bars. This basic scale structure is considered to be a generic characteristic. Finer scale details such as the shape and presence of a central hole in the basal plate, the numbers of uprights, bars and spines are considered to be species-specific. Two types of scales were found within clonal cultures of H. arctica and H. circularisquama and it is suggested that these represent ‘mature' and ‘immature' body scales. Intraspecific variation of the basal plate ‘reticulation' was also observed. This variation was particularly evident in prolonged cultures of H. horiguchii and H. rotundata. The body-scale structure of 11 described species can be distinguished. However, two species, namely H. triquetra and H. pseudotriquetra, have the same scale morphology and are distinguished by differences in cell shape and LSU rDNA (25S rDNA) sequences.
- Published
- 2004
15. Wide distribution of Nitzschia navis-varingica, a new domoic acidproducing benthic diatom found in Vietnam
- Author
-
Kotaki, Y., Lundholm, N., Onodera, H., Kobayashi, K., Bajarias, F.F.A., Furio, E.E., Iwataki, M., Fukuyo, Y., Kodama, A., Kotaki, Y., Lundholm, N., Onodera, H., Kobayashi, K., Bajarias, F.F.A., Furio, E.E., Iwataki, M., Fukuyo, Y., and Kodama, A.
- Published
- 2004
16. Poster Session 4: Friday 9 December 2011, 14:00-18:00 * Location: Poster Area
- Author
-
Wang, M., primary, Yan, G., additional, Yue, W., additional, Siu, C., additional, Tse, H., additional, Perperidis, A., additional, Cusack, D., additional, White, A., additional, Macgillivray, T., additional, Mcdicken, W., additional, Anderson, T., additional, Ryabov, V., additional, Shurupov, V., additional, Suslova, T., additional, Markov, V., additional, Elmstedt, N., additional, Ferm Widlund, K., additional, Lind, B., additional, Brodin, L.-A., additional, Westgren, M., additional, Mantovani, F., additional, Barbieri, A., additional, Bursi, F., additional, Valenti, C., additional, Quaglia, M., additional, Modena, M., additional, Peluso, D., additional, Muraru, D., additional, Dal Bianco, L., additional, Beraldo, M., additional, Solda', E., additional, Tuveri, M., additional, Cucchini, U., additional, Al Mamary, A., additional, Badano, L., additional, Iliceto, S., additional, Goncalves, A., additional, Almeria, C., additional, Marcos-Alberca, P., additional, Feltes, G., additional, Hernandez-Antolin, R., additional, Rodriguez, H., additional, Maroto, L., additional, Silva Cardoso, J., additional, Macaya, C., additional, Zamorano, J., additional, Squarciotta, S., additional, Innocenti, F., additional, Guzzo, A., additional, Bianchi, S., additional, Lazzeretti, D., additional, De Villa, E., additional, Vicidomini, S., additional, Del Taglia, B., additional, Donnini, C., additional, Pini, R., additional, Mennie, C., additional, Salmasi, A. M., additional, Kutyifa, V., additional, Nagy, V., additional, Edes, E., additional, Apor, A., additional, Merkely, B., additional, Nyrnes, S., additional, Lovstakken, L., additional, Torp, H., additional, Haugen, B., additional, Said, K., additional, Shehata, A., additional, Ashour, Z., additional, El-Tobgy, S., additional, Cameli, M., additional, Bigio, E., additional, Lisi, M., additional, Righini, F., additional, Franchi, F., additional, Scolletta, S., additional, Mondillo, S., additional, Gayat, E., additional, Weinert, L., additional, Yodwut, C., additional, Mor-Avi, V., additional, Lang, R., additional, Hrynchyshyn, N., additional, Kachenoura, N., additional, Diebold, B., additional, Khedim, R., additional, Senesi, M., additional, Redheuil, A., additional, Mousseaux, E., additional, Perdrix, L., additional, Yurdakul, S., additional, Erdemir, V., additional, Tayyareci, Y., additional, Memic, K., additional, Yildirimturk, O., additional, Aytekin, V., additional, Gurel, M., additional, Aytekin, S., additional, Gargani, L., additional, Fernandez Cimadevilla, C., additional, La Falce, S., additional, Landi, P., additional, Picano, E., additional, Sicari, R., additional, Smedsrud, M. K., additional, Gravning, J., additional, Eek, C., additional, Morkrid, L., additional, Skulstad, H., additional, Aaberge, L., additional, Bendz, B., additional, Kjekshus, J., additional, Edvardsen, T., additional, Bajraktari, G., additional, Hyseni, V., additional, Morina, B., additional, Batalli, A., additional, Tafarshiku, R., additional, Olloni, R., additional, Henein, M., additional, Mjolstad, O., additional, Snare, S., additional, Folkvord, L., additional, Helland, F., additional, Haraldseth, O., additional, Grimsmo, A., additional, Berry, M., additional, Zaghden, O., additional, Nahum, J., additional, Macron, L., additional, Lairez, O., additional, Damy, T., additional, Bensaid, A., additional, Dubois Rande, J., additional, Gueret, P., additional, Lim, P., additional, Nciri, N., additional, Issaoui, Z., additional, Tlili, C., additional, Wanes, I., additional, Foudhil, H., additional, Dachraoui, F., additional, Grapsa, J., additional, Dawson, D., additional, Nihoyannopoulos, P., additional, Gianturco, L., additional, Turiel, M., additional, Atzeni, F., additional, Sarzi-Puttini, P., additional, Stella, D., additional, Donato, L., additional, Tomasoni, L., additional, Jung, P., additional, Mueller, M., additional, Huber, T., additional, Sevilmis, G., additional, Kroetz, F., additional, Sohn, H., additional, Panoulas, V., additional, Bratsas, A., additional, Raso, R., additional, Tartarisco, G., additional, Pioggia, G., additional, Gargiulo, P., additional, Petretta, M., additional, Cuocolo, A., additional, Prastaro, M., additional, D'amore, C., additional, Vassallo, E., additional, Savarese, G., additional, Marciano, C., additional, Paolillo, S., additional, Perrone Filardi, P., additional, Aggeli, C., additional, Felekos, I., additional, Roussakis, G., additional, Poulidakis, E., additional, Pietri, P., additional, Toutouzas, K., additional, Stefanadis, C., additional, Kaladaridis, A., additional, Skaltsiotis, I., additional, Kottis, G., additional, Bramos, D., additional, Takos, D., additional, Matthaios, I., additional, Agrios, I., additional, Papadopoulou, E., additional, Moulopoulos, S., additional, Toumanidis, S., additional, Carrilho-Ferreira, P., additional, Cortez-Dias, N., additional, Jorge, C., additional, Silva, D., additional, Silva Marques, J., additional, Placido, R., additional, Santos, L., additional, Ribeiro, S., additional, Fiuza, M., additional, Pinto, F., additional, Stoickov, V., additional, Ilic, S., additional, Deljanin Ilic, M., additional, Kim, W., additional, Woo, J., additional, Bae, J., additional, Kim, K., additional, Descalzo, M., additional, Rodriguez, J., additional, Moral, S., additional, Otaegui, I., additional, Mahia, P., additional, Garcia Del Blanco, L., additional, Gonzalez Alujas, T., additional, Figueras, J., additional, Evangelista, A., additional, Garcia-Dorado, D., additional, Takeuchi, M., additional, Kaku, K., additional, Otani, K., additional, Iwataki, M., additional, Kuwaki, H., additional, Haruki, N., additional, Yoshitani, H., additional, Otsuji, Y., additional, Kukucka, M., additional, Pasic, M., additional, Unbehaun, A., additional, Dreysse, S., additional, Mladenow, A., additional, Kuppe, H., additional, Hetzer, R., additional, Rajamannan, N., additional, Tanrikulu, A., additional, Kristiansson, L., additional, Gustafsson, S., additional, Lindmark, K., additional, Henein, M. Y., additional, Evdoridis, C., additional, Stougiannos, P., additional, Thomopoulos, M., additional, Fosteris, M., additional, Spanos, P., additional, Sionis, G., additional, Giatsios, D., additional, Paschalis, A., additional, Sakellaris, C., additional, Trikas, A., additional, Yong, Z. Y., additional, Boerlage-Van Dijk, K., additional, Koch, K., additional, Vis, M., additional, Bouma, B., additional, Piek, J., additional, Baan, J., additional, Abid, L., additional, Frikha, Z., additional, Makni, K., additional, Maazoun, N., additional, Abid, D., additional, Hentati, M., additional, Kammoun, S., additional, Barbier, P., additional, Staron, A., additional, Cefalu', C., additional, Berna, G., additional, Gripari, P., additional, Andreini, D., additional, Pontone, G., additional, Pepi, M., additional, Ring, L., additional, Rana, B., additional, Ho, S., additional, Wells, F., additional, Dogan, A., additional, Karaca, O., additional, Guler, G., additional, Guler, E., additional, Gunes, H., additional, Alizade, E., additional, Agus, H., additional, Gol, G., additional, Esen, O., additional, Esen, A., additional, Turkmen, M., additional, Agricola, E., additional, Ingallina, G., additional, Ancona, M., additional, Maggio, S., additional, Slavich, M., additional, Tufaro, V., additional, Oppizzi, M., additional, Margonato, A., additional, Orsborne, C., additional, Irwin, B., additional, Pearce, K., additional, Ray, S., additional, Garcia Alonso, C., additional, Vallejo, N., additional, Labata, C., additional, Lopez Ayerbe, J., additional, Teis, A., additional, Ferrer, E., additional, Nunez Aragon, R., additional, Gual, F., additional, Pedro Botet, M., additional, Bayes Genis, A., additional, Santos, C. M., additional, Carvalho, M., additional, Andrade, M., additional, Dores, H., additional, Madeira, S., additional, Cardoso, G., additional, Ventosa, A., additional, Aguiar, C., additional, Ribeiras, R., additional, Mendes, M., additional, Petrovic, M., additional, Milasinovic, G., additional, Vujisic-Tesic, B., additional, Nedeljkovic, I., additional, Zamaklar-Trifunovic, D., additional, Petrovic, I., additional, Draganic, G., additional, Banovic, M., additional, Boricic, M., additional, Villarraga, H., additional, Molini-Griggs Bs, C., additional, Silen-Rivera Bs, P., additional, Payne Mph Ms, B., additional, Koshino Md Phd, Y., additional, Hsiao Md, J., additional, Monivas Palomero, V., additional, Mingo Santos, S., additional, Mitroi, C., additional, Garcia Lunar, I., additional, Garcia Pavia, P., additional, Castro Urda, V., additional, Toquero, J., additional, Gonzalez Mirelis, J., additional, Cavero Gibanel, M., additional, Fernandez Lozano, I., additional, Oko-Sarnowska, Z., additional, Wachowiak-Baszynska, H., additional, Katarzynska-Szymanska, A., additional, Trojnarska, O., additional, Grajek, S., additional, Bellavia, D., additional, Pellikka, P., additional, Dispenzieri, A., additional, Oh, J. K., additional, Polizzi, V., additional, Pitrolo, F., additional, Musumeci, F., additional, Miller, F., additional, Ancona, R., additional, Comenale Pinto, S., additional, Caso, P., additional, Severino, S., additional, Cavallaro, C., additional, Vecchione, F., additional, D'onofrio, A., additional, Calabro', R., additional, Maceira Gonzalez, A. M., additional, Ripoll, C., additional, Cosin-Sales, J., additional, Igual, B., additional, Salazar, J., additional, Belloch, V., additional, Cosin-Aguilar, J., additional, Pinamonti, B., additional, Iorio, A., additional, Bobbo, M., additional, Merlo, M., additional, Barbati, G., additional, Massa, L., additional, Faganello, G., additional, Di Lenarda, A., additional, Sinagra, G. F., additional, Ishizu, T., additional, Seo, Y., additional, Enomoto, M., additional, Kameda, Y., additional, Ishibashi, N., additional, Inoue, M., additional, Aonuma, K., additional, Saleh, A., additional, Matsumori, A., additional, Negm, H., additional, Fouad, H., additional, Onsy, A., additional, Hamodraka, E., additional, Paraskevaidis, I., additional, Kallistratos, M., additional, Lezos, V., additional, Zamfir, T., additional, Manetos, C., additional, Mavropoulos, D., additional, Poulimenos, L., additional, Kremastinos, D., additional, Manolis, A., additional, Citro, R., additional, Rigo, F., additional, Ciampi, Q., additional, Patella, M., additional, Provenza, G., additional, Zito, C., additional, Tagliamonte, E., additional, Rotondi, F., additional, Silvestri, F., additional, Bossone, E., additional, Beltran Correas, P., additional, Gutierrez Landaluce, C., additional, Gomez Bueno, M., additional, Segovia Cubero, J., additional, Beladan, C., additional, Matei, F., additional, Popescu, B., additional, Calin, A., additional, Rosca, M., additional, Boanta, A., additional, Enache, R., additional, Savu, O., additional, Usurelu, C., additional, Ginghina, C., additional, Ciobanu, A. O., additional, Dulgheru, R., additional, Magda, S., additional, Dragoi, R., additional, Florescu, M., additional, Vinereanu, D., additional, Robalo Martins, S., additional, Calisto, C., additional, Goncalves, S., additional, Barrigoto, I., additional, Carvalho De Sousa, J., additional, Almeida, A., additional, Nunes Diogo, A., additional, Sargento, L., additional, Satendra, M., additional, Sousa, C., additional, Lousada, N., additional, Palma Reis, R., additional, Schiano Lomoriello, V., additional, Esposito, R., additional, Santoro, A., additional, Raia, R., additional, Schiattarella, P., additional, Dores, E., additional, Galderisi, M., additional, Mansencal, N., additional, Caille, V., additional, Dupland, A., additional, Perrot, S., additional, Bouferrache, K., additional, Vieillard-Baron, A., additional, Jouffroy, R., additional, Moceri, P., additional, Liodakis, E., additional, Gatzoulis, M., additional, Li, W., additional, Dimopoulos, K., additional, Sadron, M., additional, Seguela, P. E., additional, Arnaudis, B., additional, Dulac, Y., additional, Cognet, T., additional, Acar, P., additional, Shiina, Y., additional, Uemura, H., additional, Kupczynska, K., additional, Kasprzak, J., additional, Michalski, B., additional, Lipiec, P., additional, Carvalho, V., additional, Almeida, A. M. G., additional, David, C., additional, Marques, J., additional, Ferreira, P., additional, Amaro, M., additional, Costa, P., additional, Diogo, A., additional, Tritakis, V., additional, Ikonomidis, I., additional, Lekakis, J., additional, Tzortzis, S., additional, Kadoglou, N., additional, Papadakis, I., additional, Trivilou, P., additional, Koukoulis, C., additional, Anastasiou-Nana, M., additional, Bombardini, T., additional, Gherardi, S., additional, Arpesella, G., additional, Maccherini, M., additional, Serra, W., additional, Magnani, G., additional, Del Bene, R., additional, Pasanisi, E., additional, Startari, U., additional, Panchetti, L., additional, Rossi, A., additional, Piacenti, M., additional, Morales, M., additional, El Hajjaji, I., additional, El Mahmoud, R., additional, Digne, F., additional, Dubourg, O., additional, Agoston, G., additional, Moreo, A., additional, Pratali, L., additional, Moggi Pignone, A., additional, Pavellini, A., additional, Doveri, M., additional, Musca, F., additional, Varga, A., additional, Faita, F., additional, Rimoldi, S., additional, Sartori, C., additional, Alleman, Y., additional, Salinas Salmon, C., additional, Villena, M., additional, Scherrer, U., additional, Baptista, R., additional, Serra, S., additional, Castro, G., additional, Martins, R., additional, Salvador, M., additional, Monteiro, P., additional, Silva, J., additional, Szudi, L., additional, Temesvary, A., additional, Fekete, B., additional, Kassai, I., additional, Szekely, L., additional, Abdel Moneim, S. S., additional, Martinez, M., additional, Mankad, S., additional, Bernier, M., additional, Dhoble, A., additional, Chandrasekaran, K., additional, Oh, J., additional, Mulvagh, S., additional, Hong, G. R., additional, Kim, J. Y., additional, Lee, S. C., additional, Choi, S. H., additional, Sohn, I. S., additional, Seo, H. S., additional, Choi, J. H., additional, Cho, K. I., additional, Yoon, S. J., additional, Lim, S. J., additional, Wejner-Mik, P., additional, Kusmierek, J., additional, Plachcinska, A., additional, Szuminski, R., additional, Stoebe, S., additional, Tarr, A., additional, Trache, T., additional, Hagendorff, A., additional, Jenkins, C., additional, Kuhl, H., additional, Nesser, H., additional, Marwick, T., additional, Franke, A., additional, Niel, J., additional, Sugeng, L., additional, Soderberg, S., additional, Lindqvist, P., additional, Necas, J., additional, Kovalova, S., additional, Saha, S. K., additional, Kiotsekoglou, A., additional, Toole, R., additional, Govind, S., additional, Gopal, A., additional, Amzulescu, M.-S., additional, Florian, A., additional, Bogaert, J., additional, Janssens, S., additional, Voigt, J., additional, Parisi, V., additional, Losi, M., additional, Parrella, L., additional, Contaldi, C., additional, Chiacchio, E., additional, Caputi, A., additional, Scatteia, A., additional, Buonauro, A., additional, Betocchi, S., additional, Rimbas, R., additional, Mihaila, S., additional, Caputo, M., additional, Navarri, R., additional, Innelli, P., additional, Urselli, R., additional, Capati, E., additional, Ballo, P., additional, Furiozzi, F., additional, Favilli, R., additional, Lindquist, R., additional, Miller, A., additional, Reece, C., additional, O'leary, P., additional, Cetta, F., additional, Eidem, B. W., additional, Cikes, M., additional, Gasparovic, H., additional, Bijnens, B., additional, Velagic, V., additional, Kopjar, T., additional, Biocina, B., additional, Milicic, D., additional, Ta-Shma, A., additional, Nir, A., additional, Perles, Z., additional, Gavri, S., additional, Golender, J., additional, Rein, A., additional, Pinnacchio, G., additional, Barone, L., additional, Battipaglia, I., additional, Cosenza, A., additional, Marinaccio, L., additional, Coviello, I., additional, Scalone, G., additional, Sestito, A., additional, Lanza, G., additional, Crea, F., additional, Cakal, S., additional, Eroglu, E., additional, Ozkan, B., additional, Kulahcioglu, S., additional, Bulut, M., additional, Koyuncu, A., additional, Acar, G., additional, Alici, G., additional, Dundar, C., additional, Labombarda, F., additional, Zangl, E., additional, Pellissier, A., additional, Bougle, D., additional, Maragnes, P., additional, Milliez, P., additional, Saloux, E., additional, Lagoudakou, S., additional, Gialafos, E., additional, Tsokanis, A., additional, Nagy, A., additional, Kovats, T., additional, Vago, H., additional, Toth, A., additional, Sax, B., additional, Kovacs, A., additional, Elnoamany, M. F., additional, Badran, H., additional, Abdelfattah, I., additional, Khalil, T., additional, Salama, M., additional, Butz, T., additional, Taubenberger, C., additional, Thangarajah, F., additional, Meissner, A., additional, Van Bracht, M., additional, Prull, M., additional, Yeni, H., additional, Plehn, G., additional, Trappe, H., additional, Rydman, R., additional, Bone, D., additional, Alam, M., additional, Caidahl, K., additional, Larsen, F., additional, Gasior, Z., additional, Tabor, Z., additional, Sengupta, P., additional, Liu, D., additional, Niemann, M., additional, Hu, K., additional, Herrmann, S., additional, Stoerk, S., additional, Morbach, C., additional, Knop, S., additional, Voelker, W., additional, Ertl, G., additional, Weidemann, F., additional, Cawley, P., additional, Hamilton-Craig, C., additional, Mitsumori, L., additional, Maki, J., additional, Otto, C., additional, Astrom Aneq, M., additional, Nylander, E., additional, Ebbers, T., additional, Engvall, J., additional, Arvanitis, P., additional, Flachskampf, F., additional, Duvernoy, O., additional, De Torres Alba, F., additional, Valbuena Lopez, S., additional, Guzman Martinez, G., additional, Gomez De Diego, J., additional, Rey Blas, J., additional, Armada Romero, E., additional, Lopez De Sa, E., additional, Moreno Yanguela, M., additional, Lopez Sendon, J., additional, Trikalinos, N., additional, Siasos, G., additional, Aggeli, A., additional, Tomaszewski, A., additional, Kutarski, A., additional, Tomaszewski, M., additional, Vriz, O., additional, Driussi, C., additional, Bettio, M., additional, Pavan, D., additional, Antonini Canterin, F., additional, Doltra Magarolas, A., additional, Fernandez-Armenta, J., additional, Silva, E., additional, Solanes, N., additional, Rigol, M., additional, Barcelo, A., additional, Mont, L., additional, Berruezo, A., additional, Brugada, J., additional, Sitges, M., additional, Ciciarello, F. L., additional, Mandolesi, S., additional, Fedele, F., additional, Agati, L., additional, Marceca, A., additional, Rhee, S., additional, Shin, S., additional, Kim, S., additional, Yun, K., additional, Yoo, N., additional, Kim, N., additional, Oh, S., additional, Jeong, J., additional, and Alabdulkarim, N., additional
- Published
- 2011
- Full Text
- View/download PDF
17. Wide distribution of a domoic acid-producing diatom Nitzschia navis-varingica. Abstracts, Xth International Conference on Harmful Algae, 21-25 oktober 2002, St. Pete Beach, Florida
- Author
-
Kotaki, Y., Lundholm, Nina, Onodera, H., Iwataki, M., Fukuyo, Y., Kodama, M., Kotaki, Y., Lundholm, Nina, Onodera, H., Iwataki, M., Fukuyo, Y., and Kodama, M.
- Published
- 2002
18. Strong correlation effects in the A-site ordered perovskite CaCu3Ti4O12 revealed by angle-resolved photoemission spectroscopy.
- Author
-
Im, H. J., Tsunekawa, M., Sakurada, T., Iwataki, M., Kawata, K., Watanabe, T., Takegahara, K., Miyazaki, H., Matsunami, M., Hajiri, T., and Kimura, S.
- Subjects
- *
PEROVSKITE , *PHOTOELECTRON spectroscopy , *CALCIUM compounds , *COPPER compounds , *MATERIALS science - Abstract
We report angle-resolved photoemission spectroscopy results of A-site ordered perovskite CaCu3Ti4O12. We have observed the clear band dispersions, which are shifted to the higher energy by 1.7 eV and show the band narrowing around 2 eV in comparison with the local density approximation calculations. In addition, the high-energy multiplet structures of Cu 3d8 final states have been found around 8-13 eV. These results reveal that CaCu3Ti4O12 is a Mott-type insulator caused by the strong correlation effects of the Cu 3d electrons well hybridized with O 2p states. Unexpectedly, there exists a very small spectral weight at the Fermi level in the insulator phase, indicating the existence of isolated metallic states. [ABSTRACT FROM AUTHOR]
- Published
- 2013
- Full Text
- View/download PDF
19. Phylogeny and ultrastructure of a non-toxigenic dinoflagellate Amphidoma fulgens sp. nov. (Amphidomataceae, Dinophyceae), with a wide distribution across Asian Pacific.
- Author
-
Kuwata K, Lum WM, Takahashi K, Benico G, Takahashi K, Lim PT, Leaw CP, Uchida H, Ozawa M, Matsushima R, Watanabe R, Suzuki T, and Iwataki M
- Subjects
- Japan, Pacific Ocean, Malaysia, Marine Toxins, Spiro Compounds, DNA, Ribosomal genetics, Philippines, Polyether Toxins, Dinoflagellida genetics, Dinoflagellida ultrastructure, Dinoflagellida classification, Phylogeny
- Abstract
Amphidoma languida, a marine thecate dinoflagellate that produces the lipophilic toxin azaspiracids (AZAs), is primarily found in the Atlantic. Although this species has not been recorded in the Asian Pacific, environmental DNAs related to Am. languida have been widely detected in the region by metabarcoding analysis. Their morphology and AZA production remain unclear. In this study, the morphology, ultrastructure, phylogeny, and AZA production of nine Amphidoma strains isolated from Japan, Malaysia, and Philippines were investigated. Phylogenetic trees inferred from rDNAs (SSU, ITS, and LSU rDNA) showed monophyly of the nine Pacific strains and were sister to the Am. languida clade, including the toxigenic strains from the Atlantic. Cells were ellipsoid, 8.7-16.7 µm in length and 7.4-14.0 µm in width, with a conspicuous apical pore complex. A large nucleus in the hyposome, parietal chloroplast with a spherical pyrenoid in the episome, and refractile bodies were observed. Thecal tabulation was typical of Amphidoma, Po, cp, X, 6', 6'', 6C, 5S, 6''', 2''''. A ventral pore was located on the anterior of 1' plate, beside the suture to 6' plate. The presence of a ventral depression, on the anterior of anterior sulcal plate, was different from Am. languida. A large antapical pore, containing approximately 10 small pores, was observed. Cells were apparently smaller than Am. trioculata, a species possessing three pores (ventral pore, ventral depression, and antapical pore). TEM showed the presence of crystalline structures, resembling guanine crystals, and cytoplasmic invaginations into the pyrenoid matrix. Flagellar apparatus lacking the striated root connective is similar to peridinioids and related dinoflagellates. AZAs were not detected from the Pacific strains by LC-MS/MS. This non-toxigenic Amphidoma species, here we propose as Amphidoma fulgens sp. nov., is widely distributed in the Asian Pacific. Moreover, molecular comparison also suggested that most of the environmental DNA sequences previously reported as Am. languida or related sequences from the Asian Pacific were attributable to Am. fulgens., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)
- Published
- 2024
- Full Text
- View/download PDF
20. Novel aerobic anoxygenic phototrophic bacterium Jannaschia pagri sp. nov., isolated from seawater around a fish farm.
- Author
-
Kuwata K, Sato-Takabe Y, Nakai R, Sugimura Y, Tazato N, Kunihiro T, Morohoshi S, Iwataki M, Hamasaki K, and Shiozaki T
- Subjects
- RNA, Ribosomal, 16S genetics, Japan, Aquaculture, DNA, Bacterial genetics, Photosynthesis, Bacterial Typing Techniques, Aerobiosis, Animals, Bacteriochlorophyll A analysis, Phylogeny, Seawater microbiology
- Abstract
The genus Jannaschia is one of the representatives of aerobic anoxygenic phototrophic (AAP) bacteria, which is a strictly aerobic bacterium, producing a photosynthetic pigment bacteriochlorophyll (BChl) a. However, a part of the genus Jannaschia members have not been confirmed the photosynthetic ability. The partly presence of the ability in the genus Jannaschia could suggest the complexity of evolutionary history for anoxygenic photosynthesis in the genus, which is expected as gene loss and/or horizontal gene transfer. Here a novel AAP bacterium designated as strain AI_62
T (= DSM 115720T = NBRC 115938T ), was isolated from coastal seawater around a fish farm in the Uwa Sea, Japan. Its closest relatives were identified as Jannaschia seohaensis SMK-146T (95.6% identity) and J. formosa 12N15T (94.6% identity), which have been reported to produce BChl a. The genomic characteristic of strain AI_62T clearly showed the possession of the anoxygenic photosynthesis related gene sets. This could be a useful model organism to approach the evolutionary mystery of anoxygenic photosynthesis in the genus Jannaschia. Based on a comprehensive consideration of both phylogenetic and phenotypic characteristics, we propose the classification of a novel species within the genus Jannaschia, designated as Jannaschia pagri sp. nov. The type strain for this newly proposed species is AI_62T (= DSM 115720T = NBRC 115938T )., (© 2024. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)- Published
- 2024
- Full Text
- View/download PDF
21. New azaspiracid analogues detected as bi-charged ions in Azadinium poporum (Amphidomataceae, Dinophyceae) isolated from Japanese coastal waters.
- Author
-
Ozawa M, Uchida H, Watanabe R, Numano S, Matsushima R, Oikawa H, Takahashi K, Lum WM, Benico G, Iwataki M, and Suzuki T
- Subjects
- Tandem Mass Spectrometry, Chromatography, Liquid, Japan, Marine Toxins analysis, Dinoflagellida chemistry, Spiro Compounds analysis, Polyether Toxins
- Abstract
Lipophilic marine biotoxin azaspiracids (AZAs) are produced by dinoflagellates Azadinium and Amphidoma. Recently, several strains of Azadinium poporum were isolated from Japanese coastal waters, and detailed toxin profiles of two strains (mdd421 and HM536) among them were clarified by several detection techniques on liquid chromatography-tandem mass spectrometry (LC-MS/MS) and liquid chromatography-quadrupole time of flight mass spectrometry (LC-QTOFMS). In our present study, AZA analogues in seven strains of A. poporum from Japanese coastal waters (including two previously reported strains) were determined by these detection techniques. The dominant AZA in the seven strains was AZA2 accompanied by small amounts of several known AZAs and twelve new AZA analogues. Eight of the twelve new AZA analogues discovered in our present study were detected as bi-charged ions on the positive mode LC/MS/MS. This is the first report describing AZA analogues detected as bi-charged ions with hexose and sulfate groups in their structures., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)
- Published
- 2024
- Full Text
- View/download PDF
22. Potential Effects of Mild Atrial Secondary Mitral Regurgitation in Patients With Isolated Atrial Fibrillation.
- Author
-
Akashi J, Iwataki M, Nabeshima Y, Onoue T, Hayashi A, Tanaga T, Nishino S, Kimura T, Yano M, Watanabe N, Tsuda Y, Araki M, Shibata Y, Nishimura Y, Otsuji Y, and Kataoka M
- Subjects
- Humans, Heart Atria, Echocardiography, Prognosis, Mitral Valve Insufficiency etiology, Mitral Valve Insufficiency complications, Atrial Fibrillation complications, Atrial Fibrillation diagnosis, Heart Failure
- Abstract
Background: Patients with only moderate atrial secondary mitral regurgitation (asMR) frequently develop heart failure (HF). Mechanisms of HF with moderate asMR and the impact of mild asMR remain unclarified. Although mild/moderate primary mitral regurgitation is compensated by left ventricular (LV) dilatation, the LV is not dilated in asMR. We hypothesized that patients with mild asMR without LV dilatation may have impaired hemodynamics and higher risks of subsequent symptomatic HF deterioration., Methods: Stroke volume, cardiac output, and systolic pulmonary artery pressure were measured by echocardiography in 142 patients with isolated atrial fibrillation and 30 healthy controls. The prognosis of patients with isolated atrial fibrillation was followed up., Results: In the 142 patients with isolated atrial fibrillation, asMR was no/trivial in 55, mild in 83, moderate in 4, while none had severe asMR. Compared with controls and patients with no/trivial asMR, LV end-diastolic volume index was not increased and hemodynamic parameters were abnormal in patients with mild asMR (LV end-diastolic volume index, 65±6 versus 58±8 versus 60±8 mL/m²; stroke volume index, 42±4 versus 35±4 versus 29±6 mL/m²; P <0.001 versus other 2 groups; cardiac output index, 2.8±0.4 versus 2.8±0.5 versus 2.3±0.6 L/min per m²; P <0.001; systolic pulmonary artery pressure, 21±3 versus 26±5 versus 37±9 mm Hg; P <0.001). Although the event-free rate of HF symptomatic deterioration or hospitalization in patients with no/trivial asMR during a median 13.9 months follow-up was 86.9% and 100%, the rate in mild asMR was 59.4% and 85.0% ( P <0.001 or P =0.032), respectively., Conclusions: In the presence of isolated AF and no compensatory LV dilatation, impaired hemodynamics and higher risks of symptomatic HF deterioration were associated with mild asMR, requiring further studies of causalities., Competing Interests: None.
- Published
- 2024
- Full Text
- View/download PDF
23. Survey results: status report on problems caused by sexual mismatch between sonographer and patient during echocardiography-a 2020 report of the Japanese Society of Echocardiography.
- Author
-
Iwataki M, Murata M, Fujita M, Toide H, Akasaka K, Iino T, Goda A, Takei K, Toh N, Miyasaka Y, Yamano M, Ishizu T, Nakatani S, and Yamamoto K
- Subjects
- Humans, Male, Female, Ultrasonography, Allied Health Personnel, Surveys and Questionnaires, East Asian People, Echocardiography
- Abstract
Objectives: Ultrasonography is an essential examination performed in various clinical fields. The number of clinical sonographers has been increasing. However, the working environments and conditions at each facility are different, leading to diverse problems. Among them, the emerging issue is the sexual disagreement between the sonographer and patient at the time of echocardiography. Since the patient must expose their breast during echocardiography, female patients may refuse to undergo the examination when conducted by a male sonographer. This study aimed to conduct a questionnaire survey to understand the measures for sonographer-patient gender mismatch at different facilities., Methods: A questionnaire on the implementation of echocardiography by male sonographers for female patients was answered by representatives and specialist technicians of the Japanese Society of Echocardiography., Results: Questionnaire responses were obtained from 50 facilities (59 participants). A total of 70% of the facilities restricted male sonographers from conducting echocardiography examinations for female patients. Among them, 81% of the facilities serviced female patients aged 60 years or younger., Conclusions: It has become clear that the gender selection of echocardiographic examiners varies from facility to facility, and providing a sufficient explanation before echocardiographic examination is necessary to avoid causing uncomfortable situations for female patients., (© 2022. Japanese Society of Echocardiography.)
- Published
- 2023
- Full Text
- View/download PDF
24. Azaspiracid accumulation in Japanese coastal bivalves and ascidians fed with Azadinium poporum producing azaspiracid-2 as the dominant toxin component.
- Author
-
Ozawa M, Uchida H, Watanabe R, Matsushima R, Oikawa H, Takahashi K, Iwataki M, and Suzuki T
- Subjects
- Animals, Marine Toxins, Urochordata, Bivalvia, Spiro Compounds toxicity, Dinoflagellida
- Abstract
The filter-feeding bivalves often accumulate marine toxins by feeding on toxic dinoflagellates that produce marine toxins. Azaspiracids (AZAs) are a group of lipophilic polyether toxins which have been detected in a variety of organisms in many countries. In our present study, accumulation kinetics and toxin distributions in the tissues of seven bivalve species and ascidians relevant to Japanese coastal waters were investigated by experimentally feeding a toxic dinoflagellate Azadinium poporum, which produces azaspiracid-2 (AZA2) as the dominant toxin component. All bivalve species and ascidians investigated in this study had the capability to accumulate AZA2 and no metabolites of AZA2 were detected in the bivalves and the ascidians. Japanese short-neck clams, Japanese oysters, Pacific oysters and ascidians accumulated AZA2 with the highest concentrations on the hepatopancreas, whereas the highest concentrations of AZA2 were found on the gills in surf clams and horse clams. Hard clams and cockles accumulated high levels of AZA2 in both the hepatopancreas and the gills. As far as we know, this is the first report describing detailed tissue distribution of AZAs in several bivalve species other than mussels (M. edulis) and scallops (P. maximus). Variation of accumulation rates of AZA2 in Japanese short-neck clams on different cell densities or temperatures were observed., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)
- Published
- 2023
- Full Text
- View/download PDF
25. A massive bloom of Karenia species (Dinophyceae) off the Kamchatka coast, Russia, in the fall of 2020.
- Author
-
Orlova TY, Aleksanin AI, Lepskaya EV, Efimova KV, Selina MS, Morozova TV, Stonik IV, Kachur VA, Karpenko AA, Vinnikov KA, Adrianov AV, and Iwataki M
- Subjects
- Animals, Phylogeny, Harmful Algal Bloom, Phytoplankton, Satellite Imagery, Dinoflagellida genetics
- Abstract
In the fall of 2020, a long-lasting and massive harmful algal bloom (HAB) with extensive fields of yellow sea foam was observed in relatively cold waters (7-13 °C) off the coasts of the Kamchatka Peninsula, Russia. According to the estimates based on bio-optical parameters in satellite imagery, the Kamchatka bloom 2020 lasted for two months and covered a vast area of more than 300 × 100 km. An abundance of dead fish and invertebrates, including sea urchins, sea anemones, chitons, cephalopods, bivalves were found on shore during the bloom. Animals suffered almost 100% mortality within a depth range between 5 and 20 m. To identify the causative microalgal species, light and scanning electron microscopy, Raman spectroscopy, and molecular phylogenetic approaches were used. The HAB area was estimated by the spectral analysis of satellite-derived imagery. The causative organisms were unarmored dinoflagellates of Karenia species. Their density and biomass reached 100-620 cells·mL
-1 and 1300-7700 mg·m-3 , respectively, which accounted for 31-99% of the total cell density and 82-99% of the total phytoplankton biomass in late September to mid-October. The dominant species was Karenia selliformis, and the other co-occurring kareniacean species were K. cf. cristata, K. mikimotoi, K. papilionacea, K. longicanalis, and two unidentified morphotypes of Karenia spp. The molecular phylogeny inferred from LSU rDNA and ITS region showed that K. selliformis from Kamchatka in 2020 belonged to the cold-water group I and was identical to K. selliformis strains from Hokkaido, Japan, identified in 2021. This is the first HAB event caused by K. selliformis recorded from Russian coastal waters., Competing Interests: Declaration of Competing Interest The authors of the manuscript Tatiana V. Orlova, Anatoly L Aleksanin., Ekaterina V. Lepskaya, Kseniya V. Efimova, Marina S. Selina, Tatiana V. Morosova, Inna V. Stonik, Vasily A. Kachur, Alexander A. Karpenko, Kirill A. Vinnikov, Andrey V. Adrianov, Mitsunori Iwataki "A massive bloom of Karenia species (Dinophyceae) off the Kamchatka coast, Russia, in the fail of 2020" declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)- Published
- 2022
- Full Text
- View/download PDF
26. Description of two new species Chattonella tenuiplastida sp. nov. and Chattonella malayana sp. nov. (Raphidophyceae) from South China Sea, with a report of wild fish mortality.
- Author
-
Lum WM, Lim HC, Lau WLS, Law IK, Teng ST, Benico G, Leong SCY, Takahashi K, Gu H, Lirdwitayaprasit T, Leaw CP, Lim PT, and Iwataki M
- Subjects
- Animals, DNA, Ribosomal, Fishes, Phylogeny, Phylogeography, Stramenopiles metabolism
- Abstract
Fisheries damage caused by Chattonella red tide has been recorded in Southeast Asia. Molecular studies have clarified the presence of two species, Chattonella marina complex and Chattonella subsalsa in the region, unlike East Asia that had only C. marina complex. To elucidate the phylogeography of Chattonella in Asia, further phylogenetic and morphological examinations were carried out with 33 additional culture strains, including the strains isolated during a bloom of Chattonella sp. (up to 142 cells mL
-1 ) that was associated with a wild fish mortality along the northeastern coast of Peninsular Malaysia in 2016, and those from Yellow Sea, where the Chattonella genotypes have not been determined. LSU rDNA and ITS2 trees showed five intrageneric clades in the genus Chattonella, which were clades I and II (C. subsalsa), clade III (C. marina complex) and two new clades, namely clade IV from Thailand and Malaysia, and clade V from Peninsular Malaysia. The positions of the two new clades were different in LSU rDNA and ITS2 trees. LSU rDNA divergences of clades IV and V from the other clades were ≥ 4.01% and ≥ 5.70%, while their ITS2 divergences were ≥ 7.44% and ≥ 16.43%, respectively. Three and five compensatory base changes (CBCs) were observed in the clades IV and V, respectively, when compared to each of their closest clade. Cells from clades IV and V showed similar morphology to C. marina complex and C. subsalsa clade II, including the presence of button-like granules on cell surface and oboe-shaped mucocysts. However, cell size, the number and shape of chloroplasts in Chattonella clades IV and V, and the non-stacked thylakoids penetrated the pyrenoid in C. subsalsa clade II, were distinctive. Based on the diagnostic chloroplast shape, we proposed the designation of clades IV and V to two new species, Chattonella tenuiplastida sp. nov. and Chattonella malayana sp. nov., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)- Published
- 2022
- Full Text
- View/download PDF
27. Comparative Plastid Genomics of Green-Colored Dinoflagellates Unveils Parallel Genome Compaction and RNA Editing.
- Author
-
Matsuo E, Morita K, Nakayama T, Yazaki E, Sarai C, Takahashi K, Iwataki M, and Inagaki Y
- Abstract
Dinoflagellates possess plastids that are diverse in both pigmentation and evolutionary background. One of the plastid types found in dinoflagellates is pigmented with chlorophylls a and b (Chl a + b ) and originated from the endosymbionts belonging to a small group of green algae, Pedinophyceae. The Chl a + b -containing plastids have been found in three distantly related dinoflagellates Lepidodinium spp., strain MGD, and strain TGD, and were proposed to be derived from separate partnerships between a dinoflagellate (host) and a pedinophycean green alga (endosymbiont). Prior to this study, a plastid genome sequence was only available for L. chlorophorum , which was reported to bear the features that were not found in that of the pedinophycean green alga Pedinomonas minor , a putative close relative of the endosymbiont that gave rise to the current Chl a + b -containing plastid. In this study, we sequenced the plastid genomes of strains MGD and TGD to compare with those of L. chlorophorum as well as pedinophycean green algae. The mapping of the RNA-seq reads on the corresponding plastid genome identified RNA editing on plastid gene transcripts in the three dinoflagellates. Further, the comparative plastid genomics revealed that the plastid genomes of the three dinoflagellates achieved several features, which are not found in or much less obvious than the pedinophycean plastid genomes determined to date, in parallel., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Matsuo, Morita, Nakayama, Yazaki, Sarai, Takahashi, Iwataki and Inagaki.)
- Published
- 2022
- Full Text
- View/download PDF
28. Morphological variation and phylogeny of Karenia selliformis (Gymnodiniales, Dinophyceae) in an intensive cold-water algal bloom in eastern Hokkaido, Japan.
- Author
-
Iwataki M, Lum WM, Kuwata K, Takahashi K, Arima D, Kuribayashi T, Kosaka Y, Hasegawa N, Watanabe T, Shikata T, Isada T, Orlova TY, and Sakamoto S
- Subjects
- Animals, DNA, Ribosomal genetics, Harmful Algal Bloom, Japan, Phylogeny, Water, Dinoflagellida genetics
- Abstract
Harmful algal blooms responsible for mass mortalities of marine organisms have been rare in Hokkaido, northern Japan, although fish-killing blooms have been frequently reported from western Japanese coasts. In September-November 2021, a huge and prolonged cold-water bloom occurred along the Pacific coast of eastern Hokkaido, and was associated with intensive mortalities of sea urchin, fish, octopus, shellfish, etc. In this study, morphology and phylogeny of the dominant and co-occurring unarmored dinoflagellates of the Kareniaceae in the bloom were examined by using light microscopy, scanning electron microscopy and molecular phylogeny inferred from ITS and LSU rDNA (D1-D3) sequences. Morphological observation and molecular phylogeny showed that the dominant species was Karenia selliformis, with co-occurrences of other kareniacean dinoflagellates, Kr. longicanalis, Kr. mikimotoi, Karlodinium sp., Takayama cf. acrotrocha, Takayama tuberculata and Takayama sp. The typical cell forms of Kr. selliformis in the bloom were discoid, dorsoventrally flattened, and 35.3-43.6 (39.4 ± 2.1) µm in length, which was larger than the cell sizes in previous reports. Transparent cells of Kr. selliformis, lacking chloroplasts or having a few shrunken chloroplasts and oil droplets, were also found. Cells of Kr. selliformis showed morphological variation, but the species could be distinguished from other co-occurring Karenia species by the nucleus positioned in the hypocone and chloroplasts numerous (46-105) in number and small (2.9-4.6 µm) in diameter. Cell density of Kr. selliformis exceeding 100 cells mL
-1 was recorded in the temperature range of 9.8-17.6 °C. The rDNA sequences determined from Kr. selliformis in the blooms of Hokkaido, Japan in 2021 were identical to those from the bloom in Kamchatka, Russia in 2020., (Copyright © 2022 The Author(s). Published by Elsevier B.V. All rights reserved.)- Published
- 2022
- Full Text
- View/download PDF
29. Large discrepancy in optimal atrioventricular delay between sensed and paced atrial events in a pacemaker patient.
- Author
-
Yamagishi Y, Oginosawa Y, Miki H, Yagyu K, Miyamoto T, Tsukahara K, Iwataki M, Ohe H, Kohno R, and Kataoka M
- Subjects
- Aged, Cardiac Pacing, Artificial, Heart Atria, Humans, Male, Atrioventricular Block therapy, Pacemaker, Artificial
- Abstract
A 74-year-old man experienced complete atrioventricular (AV) block 2 days after catheter ablation for right atrial (RA) macroreentrant tachycardia. We performed DDD pacemaker implantation with atrial septal pacing because other sites of pacing threshold were not acceptable. The maximum left ventricular outflow tract velocity time integral was 15.8 cm with sensed AV delay (40 ms) and 15.0 cm with paced AV delay (220 ms); however, this exceeded the pacemaker's maximum difference of 100 ms. We herein report the case of a large discrepancy in optimal AV delay intervals between sensed and paced atrial events, requiring consideration of proper pacemaker settings., (© 2021 Wiley Periodicals LLC.)
- Published
- 2022
- Full Text
- View/download PDF
30. Complex profiles of azaspiracid analogues in two culture strains of Azadinium poporum (Amphidomataceae, Dinophyceae) isolated from Japanese coastal waters determined by LC-MS/MS.
- Author
-
Ozawa M, Uchida H, Watanabe R, Matsushima R, Oikawa H, Takahashi K, Iwataki M, and Suzuki T
- Subjects
- Chromatography, Liquid, Japan, Marine Toxins analysis, Tandem Mass Spectrometry, Dinoflagellida, Spiro Compounds analysis
- Abstract
Lipophilic marine biotoxins azaspiracids (AZAs) are produced by dinoflagellates Azadinium and Amphidoma. Recently, several strains of Azadinium poporum were isolated from Japanese coastal waters. In our present study, AZA analogues in two strains (mdd421 and HM536) of A. poporum were analyzed by several detection techniques on the liquid chromatography-tandem mass spectrometry (LC-MS/MS) and liquid chromatography-quadrupole time of flight mass spectrometry (LC-QTOFMS). The dominant AZA analogue in the Japanese A. poporum strains was AZA2. Other known AZA analogues were AZA11, AZA35, AZA2 methyl ester and AZA2 phosphate ester. Besides these AZAs, thirteen new AZA analogues were discovered in the two strains. A putative AZA analogue (Compound 1) with the smallest molecular weight ever found in nature was also discovered in the two strains. This is the first report describing detailed AZA profiles in Japanese isolates of A. poporum., (Copyright © 2021 Elsevier Ltd. All rights reserved.)
- Published
- 2021
- Full Text
- View/download PDF
31. Thecal tabulation, body scale morphology and phylogeny of Heterocapsa philippinensis sp. nov. (Peridiniales, Dinophyceae) from the Philippines.
- Author
-
Benico G, Lum WM, Takahashi K, Yñiguez AT, and Iwataki M
- Subjects
- DNA, Ribosomal genetics, Dinoflagellida genetics, Dinoflagellida ultrastructure, Microscopy, Electron, Scanning, Microscopy, Electron, Transmission, Philippines, Species Specificity, Dinoflagellida classification, Phylogeny
- Abstract
The thecal tabulation and body scale structure of the marine armoured dinoflagellate Heterocapsa, isolated from Philippines, were examined using LM, SEM and TEM, and its phylogenetic position was inferred from ITS and LSU rDNA sequences. Cells were ovoid and the plate tabulation (Po, cp, X, 5', 3a, 7'', 6c, 5s, 5''', 2'''') was consistent with most Heterocapsa species. The second anterior intercalary plate (2a) had a circular pattern with a thick marginal border free of pores. The nucleus was longitudinally elongated and curved, and located at the dorsal side of the cell. Discoid lobes of brownish chloroplast were peripherally distributed, and a pyrenoid was positioned at the centre. The triradiate body scales, measuring 250-300 nm in diameter, consisted of a roundish basal plate with six radiating ridges, nine peripheral uprights/spines, and three radiating spines. These components were identical to those of H. pseudotriquetra and H. steinii, except for the roundish outline of basal plate. Molecular phylogeny showed that the species clustered with H. pseudotriquetra and H. steinii. This species was differentiated from all other Heterocapsa species in the sausage-shaped nucleus and circular pattern on the 2a plate. This study proposed a novel species Heterocapsa philippinensis sp. nov. for the isolate., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier GmbH. All rights reserved.)
- Published
- 2021
- Full Text
- View/download PDF
32. Morpho-molecular description of a new HAB species, Pseudocochlodinium profundisulcus gen. et sp. nov., and its LSU rRNA gene based genetic diversity and geographical distribution.
- Author
-
Hu Z, Xu N, Gu H, Chai Z, Takahashi K, Li Z, Deng Y, Iwataki M, Matsuoka K, and Tang YZ
- Subjects
- Genes, rRNA, Genetic Variation, Harmful Algal Bloom, Phylogeny, Dinoflagellida genetics
- Abstract
Harmful algal blooms (HABs) caused by an unknown dinoflagellate species have frequently occurred in the Pearl River Estuary, China Since 2006. These blooms were associated with severe water discoloration and economic losses, ranging from several km
2 to 300 km2 with the maximum recorded cell density being 2.77 × 107 cells⋅L-1 . This unknown dinoflagellate species was initially identified as Cochlodinium geminatum and subsequently reclassified as Polykrikos geminatus. However, after reviewing the original descriptions for Cochlodinium geminatum sensu Schütt (1895) and the genus Polykrikos, we considered this species is incongruent with their original descriptions. Further morphological examinations and particularly phylogenetic analyses based on the SSU and partial LSU rRNA genes of isolates and resting cysts from China and Japan prompted us to consider it a new species of a new genus. This new species was proposed to be Pseudocochlodinium profundisulcus gen. et sp. nov., based on its open comma-shaped apical structure complex (ASC), cingulum encircling the cell less than one and a half turns, a deep sulcus with a torsion of a half turn, either single cell or cell chain consisting of two cells with the same number of nuclei and zooids, the resting cyst bearing lobed ornaments, and the evolutionary distances from Polykrikos (and others) on the phylogenetic trees constructed using the concatenated SSU and partial LSU rRNA gene sequences. Metabarcoding investigation of surface sediment samples collected in China revealed that the species to be widely present along the entire Chinese coast with the highest abundance in the South China Sea. Further re-analysis of the Tara Oceans metabarcoding dataset targeting the SSU rRNA gene V9 domain suggested a global distribution of this new genus. Phylogenetic analyses on 46 OTUs (average length: ∼552 bases) of its LSU rRNA gene sequences (mainly D1-D2 domains) obtained from surface sediment samples revealed intraspecific genetic diversity of this species. Interestingly, based on the different distributions and the abundance of these OTUs along the coast of China, this species appeared to have expanded its distribution from the South China Sea to the northern Yellow Sea, or preferred a warm water habitat. We consider that the present work improves the taxonomy and provides important insights into the biogeography of Pseudocochlodinium profundisulcus.⋅., (Copyright © 2021 Elsevier B.V. All rights reserved.)- Published
- 2021
- Full Text
- View/download PDF
33. The harmful raphidophyte Chattonella (Raphidophyceae) in Western Pacific: Its red tides and associated fisheries damage over the past 50 years (1969-2019).
- Author
-
Lum WM, Benico G, Doan-Nhu H, Furio E, Leaw CP, Leong SCY, Lim PT, Lim WA, Lirdwitayaprasit T, Lu S, Muawanah, Nguyen NV, Orlova TY, Rachman A, Sakamoto S, Takahashi K, Teng ST, Thoha H, Wang P, Yñiguez AT, Wakita K, and Iwataki M
- Subjects
- Animals, Asia, Southeastern, Fisheries, Philippines, Harmful Algal Bloom, Stramenopiles
- Abstract
Red tides and associated fisheries damage caused by the harmful raphidophyte Chattonella were reassessed based on the documented local records for 50 years to understand the distribution and economic impacts of the harmful species in the Western Pacific. Blooms of Chattonella with fisheries damage have been recorded in East Asia since 1969, whereas they have been only recorded in Southeast Asia since the 1980s. Occurrences of Chattonella have been documented from six Southeast Asian countries, Indonesia, Malaysia, Philippines, Singapore, Thailand and Viet Nam, with mass mortalities mainly of farmed shrimp in 1980-1990s, and farmed fish in 2000-2010s. These occurrences have been reported with the names of C. antiqua, C. marina, C. ovata, C. subsalsa and Chattonella sp., owing to the difficulty of microscopic species identification, and many were not supported with molecular data. To determine the distribution of C. marina complex and C. subsalsa in Southeast Asia, molecular phylogeny and microscopic observation were also carried out for cultures obtained from Indonesia, Malaysia, Japan, Philippines, Russia, Singapore and Thailand. The results revealed that only the genotype of C. marina complex has been detected from East Asia (China, Japan, Korea and Russia), whereas both C. marina complex (Indonesia and Malaysia) and C. subsalsa (Philippines, Singapore and Thailand) were found in Southeast Asia. Ejection of mucocysts has been recognized as a diagnostic character of C. subsalsa, but it was also observed in our cultures of C. marina isolated from Indonesia, Malaysia, Japan, and Russia. Meanwhile, the co-occurrences of the two harmful Chattonella species in Southeast Asia, which are difficult to distinguish solely based on their morphology, suggest the importance of molecular identification of Chattonella genotypes for further understanding of their distribution and negative impacts., (Copyright © 2021 The Author(s). Published by Elsevier B.V. All rights reserved.)
- Published
- 2021
- Full Text
- View/download PDF
34. Discrepancy of Aortic Valve Area Measurements by Doppler vs. Biplane Stroke Volume Measurements and Utility of Combining the Different Areas in Aortic Valve Stenosis - The Asian Valve Registry.
- Author
-
Iwataki M, Kim YJ, Park SW, Ling LH, Yu CM, Okura H, Ha JW, Hozumi T, Tanaka H, Izumi C, Yuasa T, Song JK, Otsuji Y, and Sohn DW
- Subjects
- Humans, Prospective Studies, Registries, Severity of Illness Index, Stroke Volume, Ventricular Function, Left, Aortic Valve diagnostic imaging, Aortic Valve surgery, Aortic Valve Stenosis diagnostic imaging, Aortic Valve Stenosis surgery
- Abstract
Background: The aortic valve area index (AVAI) in aortic stenosis (AS) is measured by echocardiography with a continuity equation using the stroke volume index by Doppler (SVI
Doppler ) or biplane Simpson (SVIBiplane ) method. AVAIDoppler and AVAIBiplane often show discrepancy due to differences between SVIDoppler and SVIBiplane . The degree of discrepancy and utility of combined AVAIs have not been investigated in a large population of AS patients, and the characteristics of subjects with larger discrepancies are unknown., Methods and results: We studied 820 patients with significant AS (AVADoppler <1.5 cm2 ) enrolled in the Asian Valve Registry, a prospective multicenter registry at 12 Asian centers. All-cause death and aortic valve replacement were defined as events. SVIDoppler was significantly larger than SVIBiplane (49±11 vs. 39±11 mL/m2 , P<0.01) and AVAIDoppler was larger than AVAIBiplane (0.51±0.15 vs. 0.41±0.14 cm2 /m2 , P<0.01). An increase in (AVAIDoppler - AVAIBiplane ) correlated with shorter height, lower weight, older age, smaller left ventricular (LV) diameter and increased velocity of ejection flow at the LV outflow tract. Severe AS by AVAIDoppler or AVAIBiplane enabled prediction of events, and combining these AVAIs improved the predictive value of each., Conclusions: Discrepancy in AVAI by Doppler vs. biplane method was significantly more pronounced with increased LV outflow tract flow velocity, shorter height, lower weight, older age and smaller LV cavity dimensions. Combining the AVAIs enabled mutual and incremental value in predicting events.- Published
- 2021
- Full Text
- View/download PDF
35. Over 30 years of HABs in the Philippines and Malaysia: What have we learned?
- Author
-
Yñiguez AT, Lim PT, Leaw CP, Jipanin SJ, Iwataki M, Benico G, and Azanza RV
- Subjects
- Animals, Harmful Algal Bloom, Malaysia, Philippines, Dinoflagellida, Shellfish Poisoning
- Abstract
In the Southeast Asian region, the Philippines and Malaysia are two of the most affected by Harmful Algal Blooms (HABs). Using long-term observations of HAB events, we determined if these are increasing in frequency and duration, and expanding across space in each country. Blooms of Paralytic Shellfish Toxin (PST)-producing species in the Philippines did increase in frequency and duration during the early to mid-1990s, but have stabilized since then. However, the number of sites affected by these blooms continue to expand though at a slower rate than in the 1990s. Furthermore, the type of HABs and causative species have diversified for both toxic blooms and fish kill events. In contrast, Malaysia showed no increasing trend in the frequency of toxic blooms over the past three decades since Pyrodinium bahamense was reported in 1976. However, similar to the Philippines, other PST producers such as Alexandrium minutum and Alexandrium tamiyavanichii have become a concern. No amnesic shellfish poisoning (ASP) has been confirmed in either Philippines or Malaysia thus far, while ciguatera fish poisoning cases are known from the Philippines and Malaysia but the causative organisms remain poorly studied. Since the 1990s and early 2000s, recognition of the distribution of other PST-producing species such as species of Alexandrium and Gymnodinium catenatum in Southeast Asia has grown, though there has been no significant expansion in the known distributions within the last decade. A major more recent problem in the two countries and for Southeast Asia in general are the frequent fish-killing algal blooms of various species such as Prorocentrum cordatum, Margalefidinium polykrikoides, Chattonella spp., and unarmored dinoflagellates (e.g., Karlodinium australe and Takayama sp.). These new sites affected and the increase in types of HABs and causative species could be attributed to various factors such as introduction through mariculture and eutrophication, and partly because of increased scientific awareness. These connections still need to be more concretely investigated. The link to the El Niño Southern Oscillation (ENSO) should also be better understood if we want to discern how climate change plays a role in these patterns of HAB occurrences., (Copyright © 2020 Elsevier B.V. All rights reserved.)
- Published
- 2021
- Full Text
- View/download PDF
36. Harmful algal blooms and associated fisheries damage in East Asia: Current status and trends in China, Japan, Korea and Russia.
- Author
-
Sakamoto S, Lim WA, Lu D, Dai X, Orlova T, and Iwataki M
- Subjects
- Animals, China, Asia, Eastern, Hong Kong, Japan, Republic of Korea, Russia, Fisheries, Harmful Algal Bloom
- Abstract
Occurrences of harmful algal blooms (HABs) and associated fisheries damage have been continuously monitored since the 1970s along the coasts of East Asia. Fisheries damage comprises mass mortalities of fish and shellfish mainly by harmful dinoflagellates and raphidophytes (e.g., Chattonella antiqua/marina, Cochlodinium polykrikoides and Karenia mikimotoi), and contamination of algal toxins in shellfish in particular Diarrhetic Shellfish Toxins by Dinophysis spp. and Paralytic Shellfish Toxins by Alexandrium spp. Shellfish mass mortalities due to Heterocapsa circularisquama in Hong Kong and western Japan, and fish kills by Karlodinium digitatum are unique incidents for this region, whereas C. antiqua/marina, C. polykrikoides and K. mikimotoi are common also in other regions. Time series data showed that the highest bloom numbers were recorded in 1980 (Japan), in 1998 (Korea) and in 2003 (China), followed by decreasing trends in these countries. These data suggest a shift in microalgal species composition, from dominance by diatoms to dinoflagellates after 1980s in Korea, and from diatoms to small haptophytes and cyanobacteria after 2013 in eastern Russia. HAB species composition and the changes were compared among countries, for better understanding on current status and trend of HAB species in East Asia., (Copyright © 2020 Elsevier B.V. All rights reserved.)
- Published
- 2021
- Full Text
- View/download PDF
37. Perceived global increase in algal blooms is attributable to intensified monitoring and emerging bloom impacts.
- Author
-
Hallegraeff GM, Anderson DM, Belin C, Bottein MY, Bresnan E, Chinain M, Enevoldsen H, Iwataki M, Karlson B, McKenzie CH, Sunesen I, Pitcher GC, Provoost P, Richardson A, Schweibold L, Tester PA, Trainer VL, Yñiguez AT, and Zingone A
- Abstract
Global trends in the occurrence, toxicity and risk posed by harmful algal blooms to natural systems, human health and coastal economies are poorly constrained, but are widely thought to be increasing due to climate change and nutrient pollution. Here, we conduct a statistical analysis on a global dataset extracted from the Harmful Algae Event Database and Ocean Biodiversity Information System for the period 1985-2018 to investigate temporal trends in the frequency and distribution of marine harmful algal blooms. We find no uniform global trend in the number of harmful algal events and their distribution over time, once data were adjusted for regional variations in monitoring effort. Varying and contrasting regional trends were driven by differences in bloom species, type and emergent impacts. Our findings suggest that intensified monitoring efforts associated with increased aquaculture production are responsible for the perceived increase in harmful algae events and that there is no empirical support for broad statements regarding increasing global trends. Instead, trends need to be considered regionally and at the species level.
- Published
- 2021
- Full Text
- View/download PDF
38. Novel noninvasive estimation of mixed venous oxygen saturation by echocardiography and expired gas analysis.
- Author
-
Onoue T, Iwataki M, Araki M, Akashi J, Kitano T, Nabeshima Y, Hei S, Nagata Y, Hayashi A, Tsuda Y, Sonoda S, Fujino Y, Levine RA, and Otsuji Y
- Subjects
- Aged, Aged, 80 and over, Breath Tests methods, Cardiac Output, Female, Humans, Male, Middle Aged, Echocardiography methods, Exhalation, Oximetry methods, Oxygen blood, Oxygen Consumption, Veins physiology
- Abstract
Mixed venous oxygen (O
2 ) saturation ([Formula: see text]) is an important measure for evaluating the sufficiency of cardiac output (CO) relative to whole body O2 consumption (V̇o2 ), while clinical use is limited to the required invasive catheterization. According to Fick's equation, V̇o2 (mL/min) = CO (L/min) × Hb (g/dL) × 1.36 (mL/g) × ([Formula: see text] - [Formula: see text])/10 (Hb = hemoglobin concentration, [Formula: see text] = arterial blood O2 saturation). Because V̇o2 , CO, Hb, and [Formula: see text] can be measured noninvasively with expired gas analysis, echocardiography, a simple blood test, and percutaneous O2 saturation, respectively, [Formula: see text] can be calculated noninvasively. We hypothesized that noninvasively calculated [Formula: see text] shows a significant correlation and agrees well with invasively measured [Formula: see text]. In 47 patients (29 men; mean age, 70 ± 12 yr) who underwent right heart catheterization, [Formula: see text] was directly measured by sampling pulmonary artery blood. Noninvasively calculated [Formula: see text] was also obtained by the method described above. The calculated [Formula: see text] was significantly correlated with the measured [Formula: see text] ( r = 0.79, P < 0.001) and was significantly smaller than the measured [Formula: see text] (70 ± 5.1 vs. 72.1 ± 4.9%, P < 0.001). Bias at [Formula: see text] was -2.2% (95% confidence interval, -3.2 to -1.1%) with limits of agreement from -9.5 to 5.2%, demonstrating acceptable agreement. The optimal cutoff value of calculated [Formula: see text] was 69% for reduced measured [Formula: see text] < 70% with an area under the curve of 0.94. Reduced calculated [Formula: see text] < 69% indicated a sensitivity of 92.9% and a specificity of 90.9% for reduced measured [Formula: see text] < 70%. Noninvasive [Formula: see text] calculated from echocardiography, expired gas analysis, percutaneous arterial blood O2 saturation, and hemoglobin level significantly correlated and agreed well with direct [Formula: see text] measured by catheterization. This novel method allows for practical evaluation of [Formula: see text] to assess the sufficiency of CO according to whole body metabolism. NEW & NOTEWORTHY Clinical use of mixed venous oxygen saturation ([Formula: see text]) is limited to the required invasive procedure. With Fick's equation, expired gas analysis, echocardiography, simple blood tests, and percutaneous oxygen saturation, [Formula: see text] can be calculated noninvasively. We hypothesized that noninvasively calculated [Formula: see text] shows a significant correlation and agrees well with invasively measured [Formula: see text]. The present study examined the relationship between measured [Formula: see text] and calculated [Formula: see text] in patients who underwent right heart catheterization and demonstrated acceptable agreement. This novel method can expand the indication of evaluating [Formula: see text].- Published
- 2020
- Full Text
- View/download PDF
39. The Harmful Unarmored Dinoflagellate Karlodinium in Japan and Philippines, with Reference to Ultrastructure and Micropredation of Karlodinium azanzae sp. nov. (Kareniaceae, Dinophyceae) 1 .
- Author
-
Benico G, Takahashi K, Lum WM, Yñiguez AT, and Iwataki M
- Subjects
- DNA, Ribosomal, Japan, Philippines, Phylogeny, Dinoflagellida genetics
- Abstract
In all, 26 cultures of the harmful marine dinoflagellate Karlodinium, isolated from Japanese and Philippine coastal waters, were examined using LM, SEM, and molecular phylogeny inferred from ITS and LSU rDNA. Seven Karlodinium species (six from Japan and four from Philippines), K. australe, K. ballantinum, K. decipiens, K. gentienii, K. veneficum, K. zhouanum, and a novel species Karlodinium azanzae sp. nov., were identified based on their morphology and phylogenetic positions. Karlodinium azanzae from Manila Bay, Philippines was further characterized by TEM, HPLC (chloroplast pigment), and bioassay on brine shrimp and other marine zooplankton. Cells of K. azanzae were the largest (mean 25.3 µm long) in Karlodinium, possessed numerous tiny reflective particles, starch grains, and lipid granules, and usually swam at the bottom of the culture vessel. The straight apical structure complex and a ventral pore were common to the genus. The longitudinally elongated nucleus was located at the center, and the yellowish chloroplasts contained an embedded pyrenoid and carotenoid pigments typical of the genus (i.e., fucoxanthin as major carotenoid with its derivatives). TEM revealed a part of the flagellar apparatus, of which the long striated ventral connective is the first report in the Kareniaceae. Phylogenetic trees showed closest affinity of K. azanzae with K. australe and K. armiger. The new species could be differentiated from related species by cell size, position of the nucleus, and characteristic swimming behavior. Lethality of K. azanzae to large zooplankton and micropredation using a developed peduncle was also observed., (© 2020 Phycological Society of America.)
- Published
- 2020
- Full Text
- View/download PDF
40. Morphological and phylogenetic data do not support the split of Alexandrium into four genera.
- Author
-
Mertens KN, Adachi M, Anderson DM, Band-Schmidt CJ, Bravo I, Brosnahan ML, Bolch CJS, Calado AJ, Carbonell-Moore MC, Chomérat N, Elbrächter M, Figueroa RI, Fraga S, Gárate-Lizárraga I, Garcés E, Gu H, Hallegraeff G, Hess P, Hoppenrath M, Horiguchi T, Iwataki M, John U, Kremp A, Larsen J, Leaw CP, Li Z, Lim PT, Litaker W, MacKenzie L, Masseret E, Matsuoka K, Moestrup Ø, Montresor M, Nagai S, Nézan E, Nishimura T, Okolodkov YB, Orlova TY, Reñé A, Sampedro N, Satta CT, Shin HH, Siano R, Smith KF, Steidinger K, Takano Y, Tillmann U, Wolny J, Yamaguchi A, and Murray S
- Subjects
- Phylogeny, Dinoflagellida
- Abstract
A recently published study analyzed the phylogenetic relationship between the genera Centrodinium and Alexandrium, confirming an earlier publication showing the genus Alexandrium as paraphyletic. This most recent manuscript retained the genus Alexandrium, introduced a new genus Episemicolon, resurrected two genera, Gessnerium and Protogonyaulax, and stated that: "The polyphyly [sic] of Alexandrium is solved with the split into four genera". However, these reintroduced taxa were not based on monophyletic groups. Therefore this work, if accepted, would result in replacing a single paraphyletic taxon with several non-monophyletic ones. The morphological data presented for genus characterization also do not convincingly support taxa delimitations. The combination of weak molecular phylogenetics and the lack of diagnostic traits (i.e., autapomorphies) render the applicability of the concept of limited use. The proposal to split the genus Alexandrium on the basis of our current knowledge is rejected herein. The aim here is not to present an alternative analysis and revision, but to maintain Alexandrium. A better constructed and more phylogenetically accurate revision can and should wait until more complete evidence becomes available and there is a strong reason to revise the genus Alexandrium. The reasons are explained in detail by a review of the available molecular and morphological data for species of the genera Alexandrium and Centrodinium. In addition, cyst morphology and chemotaxonomy are discussed, and the need for integrative taxonomy is highlighted., (Crown Copyright © 2020. Published by Elsevier B.V. All rights reserved.)
- Published
- 2020
- Full Text
- View/download PDF
41. Potential mechanism of left ventricular spherical remodeling: association of mitral valve complex-myocardium longitudinal tissue remodeling mismatch.
- Author
-
Nagata Y, Iwataki M, Nabeshima Y, Hei S, Onoue T, Hayashi A, Otani K, Tsuda Y, Araki M, Kim DH, Song JK, Hayashida A, Toki M, Yuasa T, Mizukami N, Nishimura Y, Levine RA, and Otsuji Y
- Subjects
- Adult, Aged, Aged, 80 and over, Aortic Valve Insufficiency diagnostic imaging, Cardiomyopathy, Dilated diagnostic imaging, Echocardiography, Female, Heart Failure diagnostic imaging, Humans, Japan, Male, Middle Aged, Mitral Valve diagnostic imaging, Retrospective Studies, Seoul, Ventricular Dysfunction, Left diagnostic imaging, Aortic Valve Insufficiency physiopathology, Cardiomyopathy, Dilated physiopathology, Heart Failure physiopathology, Mitral Valve physiopathology, Ventricular Dysfunction, Left physiopathology, Ventricular Function, Left, Ventricular Remodeling
- Abstract
Since mitral valve (MV) complex (MVC) longitudinally bridges left ventricular (LV) base end and its middle, insufficient MVC longitudinal tissue length (TL) elongation relative to whole LV myocardial longitudinal TL elongation could limit LV-base-longitudinal-TL elongation, leading to predominant LV-base-transverse-TL elongation, constituting LV spherical remodeling. In 30 patients with dilated cardiomyopathy (DCM), 30 with aortic regurgitation (AR), and 30 controls, LV sphericity, LV-apex- or base-transverse- and longitudinal-TL, MVC-longitudinal-TL, and whole-LV-longitudinal-TL were measured by three-dimensional (3D) echocardiography. Ratio of each measure versus mean normal value (i.e., LV-apex-transverse-TL ratio) was considered to express the directional and regional tissue elongation. [LV-base-longitudinal-TL ratio/global-LV-TL ratio] and [MVC-longitudinal-TL ratio/whole-LV-longitudinal-TL ratio] were obtained as the degree of LV-base-longitudinal-TL or MVC-longitudinal-TL elongation relative to the whole LV elongation. LV-apex-transverse-, LV-apex-longitudinal-, and LV-base-transverse-TL ratios were significantly increased (1.27 to 1.42, P < 0.01) in both DCM and AR, while the LV-base-longitudinal-TL ratio was not increased in DCM [1.04 ± 0.19, not significant (ns)] and only modestly increased in AR (1.12 ± 0.21, P < 0.01). Whole-LV-longitudinal-TL ratio was significantly increased in both DCM and AR (1.22 ± 0.18 and 1.20 ± 0.16, P < 0.01), while MVC-longitudinal-TL ratio was not or only modestly increased in both groups (1.07 ± 0.15, ns, and 1.12 ± 0.17, P = 0.02, respectively). Multivariable analysis revealed that LV sphericity was independently related to a reduced [LV-base-longitudinal-TL ratio/global-LV-TL ratio] (standard β = -0.42, P < 0.01), which was further related to a reduced [MVC-longitudinal-TL ratio/whole-LV-longitudinal-TL ratio] (standard β = 0.72, P < 0.01). These are consistent with the hypothesis that relatively less MVC-longitudinal-TL elongation in the process of primary LV myocardial tissue elongation may limit LV-base-longitudinal-TL elongation, contributing to LV spherical remodeling. NEW & NOTEWORTHY Left ventricular (LV) spherical remodeling is associated with poor prognosis and less-effective cardiac performance, which commonly develops in dilated cardiomyopathy. However, its mechanism remains unclear. We hypothesized and subsequently clarified that less mitral valve complex (MVC) tissue longitudinal elongation relative to whole LV myocardial tissue longitudinal elongation is related to disproportionately less LV base longitudinal versus transverse myocardial tissue elongation, constituting spherical remodeling. This study suggests modification of MVC tissue elongation could be potential therapeutic targets.
- Published
- 2020
- Full Text
- View/download PDF
42. Putative genome features of relic green alga-derived nuclei in dinoflagellates and future perspectives as model organisms.
- Author
-
Nakayama T, Takahashi K, Kamikawa R, Iwataki M, Inagaki Y, and Tanifuji G
- Abstract
Nucleomorphs, relic endosymbiont nuclei, have been studied as a model to elucidate the evolutionary process of integrating a eukaryotic endosymbiont into a host cell organelle. Recently, we reported two new dinoflagellates possessing nucleomorphs, and proposed them as new models in this research field based on the following findings: genome integration processes are incomplete, and the origins of the endosymbiont lineages were pinpointed. Here, we focused on the nucleomorph genome features in the two green dinoflagellates and compared them with those of the known nucleomorph genomes of cryptophytes and chlorarachniophytes. All nucleomorph genomes showed similar trends suggesting convergent evolution. However, the number of nucleomorph genes that are unrelated to housekeeping machineries in the two green dinoflagellates are greater than the numbers in cryptophytes and chlorarachniophytes, providing additional evidence that their genome reduction has not progressed much compared with those of cryptophytes and chlorarachniophytes. Finally, potential future work is discussed., Competing Interests: No potential conflict of interest was reported by the authors., (© 2020 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.)
- Published
- 2020
- Full Text
- View/download PDF
43. Ultrastructure and Systematics of Two New Species of Dinoflagellate, Paragymnodinium Asymmetricum sp. nov. and Paragymnodinium Inerme sp. nov. (Gymnodiniales, Dinophyceae) 1 .
- Author
-
Yokouchi K, Takahashi K, Nguyen VN, Iwataki M, and Horiguchi T
- Subjects
- DNA, Ribosomal, Japan, Phylogeny, Vietnam, Dinoflagellida genetics
- Abstract
The genus Paragymnodinium currently includes two species, P. shiwhaense and P. stigmaticum, that are characterized by mixotrophic nutrition and the possession of nematocysts. In this study, two new dinoflagellates belonging to this genus were described based on observations using LM, SEM, and TEM together with a molecular analysis. Cells of P. asymmetricum sp. nov., isolated from Nha Trang Beach, Vietnam, were 7.9-12.6 μm long and 4.7-9.0 μm wide. The species showed no evidence of feeding behavior and was able to sustain itself phototrophically. Paragymnodinium asymmetricum shared many features with P. shiwhaense, including presence of nematocysts, absence of an eyespot, and a planktonic lifestyle, but was clearly distinguished by the asymmetric shape of the hyposome, possession of a single chloroplast, and its nutritional mode. Cells of P. inerme sp. nov., isolated from Jogashima, Kanagawa Pref, Japan, were 15.3-23.7 μm long and 10.9-19.6 μm wide. This species also showed no evidence of feeding behavior. Paragymnodinium inerme was similar to cells of P. shiwhaense in shape and planktonic lifestyle, but its nutritional mode was different. The presence of incomplete nematocysts was also a unique feature. A phylogenetic analysis inferred from concatenated SSU and LSU rDNA sequences recovered the two dinoflagellates in a robust clade with Paragymnodinium spp., within the clade of Gymnodinium sensu stricto. This evidence, together with their morphological similarities, made it reasonable to conclude that these two dinoflagellates are new species of Paragymnodinium., (© 2020 Phycological Society of America.)
- Published
- 2020
- Full Text
- View/download PDF
44. Dinoflagellates with relic endosymbiont nuclei as models for elucidating organellogenesis.
- Author
-
Sarai C, Tanifuji G, Nakayama T, Kamikawa R, Takahashi K, Yazaki E, Matsuo E, Miyashita H, Ishida KI, Iwataki M, and Inagaki Y
- Subjects
- Cell Nucleus genetics, Cell Nucleus physiology, Cercozoa classification, Cercozoa genetics, Chlorophyta classification, Chlorophyta physiology, Chlorophyta ultrastructure, Cryptophyta classification, Cryptophyta genetics, Dinoflagellida classification, Dinoflagellida genetics, Models, Biological, Phylogeny, Plastids genetics, Cercozoa ultrastructure, Cryptophyta ultrastructure, Dinoflagellida ultrastructure, Evolution, Molecular, Genome, Plastid, Plastids physiology, Symbiosis
- Abstract
Nucleomorphs are relic endosymbiont nuclei so far found only in two algal groups, cryptophytes and chlorarachniophytes, which have been studied to model the evolutionary process of integrating an endosymbiont alga into a host-governed plastid (organellogenesis). However, past studies suggest that DNA transfer from the endosymbiont to host nuclei had already ceased in both cryptophytes and chlorarachniophytes, implying that the organellogenesis at the genetic level has been completed in the two systems. Moreover, we have yet to pinpoint the closest free-living relative of the endosymbiotic alga engulfed by the ancestral chlorarachniophyte or cryptophyte, making it difficult to infer how organellogenesis altered the endosymbiont genome. To counter the above issues, we need novel nucleomorph-bearing algae, in which endosymbiont-to-host DNA transfer is on-going and for which endosymbiont/plastid origins can be inferred at a fine taxonomic scale. Here, we report two previously undescribed dinoflagellates, strains MGD and TGD, with green algal endosymbionts enclosing plastids as well as relic nuclei (nucleomorphs). We provide evidence for the presence of DNA in the two nucleomorphs and the transfer of endosymbiont genes to the host (dinoflagellate) genomes. Furthermore, DNA transfer between the host and endosymbiont nuclei was found to be in progress in both the MGD and TGD systems. Phylogenetic analyses successfully resolved the origins of the endosymbionts at the genus level. With the combined evidence, we conclude that the host-endosymbiont integration in MGD/TGD is less advanced than that in cryptophytes/chrorarachniophytes, and propose the two dinoflagellates as models for elucidating organellogenesis., Competing Interests: The authors declare no competing interest.
- Published
- 2020
- Full Text
- View/download PDF
45. Relations of Augmented Systolic Annular Expansion and Leaflet/Papillary Muscle Dynamics in Late-Systolic Mitral Valve Prolapse Evaluated by Echocardiography with a Speckle Tracking Analysis.
- Author
-
Hei S, Iwataki M, Jang JY, Kuwaki H, Fukuda S, Kim YJ, Toki M, Onoue T, Hayashi A, Nishino S, Watanabe N, Hayashida A, Tsuda Y, Araki M, Nishimura Y, Song JK, Yoshida K, Levine RA, and Otsuji Y
- Subjects
- Aged, Female, Humans, Male, Middle Aged, Mitral Valve diagnostic imaging, Mitral Valve Prolapse diagnostic imaging, Papillary Muscles diagnostic imaging, Retrospective Studies, Systole, Echocardiography methods, Mitral Valve physiopathology, Mitral Valve Prolapse physiopathology, Papillary Muscles physiopathology
- Abstract
The mechanism of systolic annular expansion in mitral valve prolapse (MVP) is not clarified. Since annular expansion is systolic outward shift of MV leaflet/chorda tissue complex at superior and outer ends, annular expansion could be related to inward (superior) shift of the complex at another inferior and inner end of the papillary muscle (PM) tip and/or systolic lengthening of the tissue complex, especially MV leaflets.MV annulus systolic expansion, PMs' systolic superior shift, and MV leaflets' systolic lengthening were evaluated by echocardiography with a speckle tracking analysis in 25 normal subjects, 25 subjects with holo-systolic MVP and 20 subjects with late-systolic MVP.PMs' superior shift, MV leaflets' lengthening, MV annular area at the onset of systole and subsequent MV annulus expansion were significantly greater in late-systolic MVP than in holo-systolic MVP (4.6 ± 1.6 versus 1.5 ± 0.7 mm/m
2 , 2.5 ± 1.4 versus 0.6 ± 2.0 mm/m2 , 6.8 ± 2.5 versus 5.7 ± 1.0 cm2 /m2 and 1.6 ± 0.8 versus 0.1 ± 0.5 cm2 /m2 , P < 0.001, respectively). Multivariate analysis identified MV leaflets' lengthening and PMs' superior shift as independent factors associated with MV annular expansion.Conclusions: These results suggest that systolic MV annular expansion in MVP is related to abnormal MV leaflets' lengthening and PMs' superior shift.- Published
- 2020
- Full Text
- View/download PDF
46. [A Case of Change from Normal-flow High-pressure Gradient Severe Aortic Stenosis to Paradoxical Low-flow Low-pressure Gradient Severe Aortic Stenosis].
- Author
-
Onoue T, Araki M, Iwataki M, Hayashi A, and Otsuji Y
- Subjects
- Aged, Aortic Valve Stenosis complications, Aortic Valve Stenosis diagnostic imaging, Aortic Valve Stenosis pathology, Cardiac Output, Low, Disease Progression, Echocardiography, Heart Ventricles pathology, Humans, Male, Oxygen Consumption, Severity of Illness Index, Stomach Neoplasms complications, Stroke Volume, Aortic Valve Stenosis physiopathology
- Abstract
We report a case of a 77-year-old male who had been diagnosed with normal-flow high-pressure gradient severe aortic stenosis (AS) two years previously. In accordance with his wishes, it was decided not to perform surgery. He visited our hospital with anorexia and weight loss and was diagnosed with gastric cancer. Echocardiography showed a change to paradoxical low-flow low-pressure gradient severe AS (PLFLPG AS). A decrease in stroke volume is typically associated with a smaller LV size, but the reason for a smaller LV size in PLFLPG AS remains unclear. In this case, the change to PLFLPG AS was thought to be due to a decrease in whole body oxygen consumption, and this may help to understand the pathology.
- Published
- 2020
- Full Text
- View/download PDF
47. Prevention of serious air embolism during cryoballoon ablation; risk assessment of air intrusion into the sheath by catheter selection and change in intrathoracic pressure: An ex vivo study.
- Author
-
Tsukahara K, Oginosawa Y, Fujino Y, Ohe H, Yamagishi Y, Iwataki M, Sonoda S, Kohno R, Otsuji Y, and Abe H
- Subjects
- Atrial Function, Left, Atrial Pressure, Cardiac Catheterization adverse effects, Cryosurgery adverse effects, Embolism etiology, Embolism physiopathology, Equipment Design, Humans, Materials Testing, Risk Factors, Cardiac Catheterization instrumentation, Cardiac Catheters, Cryosurgery instrumentation, Embolism prevention & control
- Abstract
Introduction: One cause of cerebral infarction during cryoballoon ablation is the entry of air into a sheath due to the use of inappropriate catheters. It is known that the left atrial pressure of patients with obstructive sleep apnea syndrome can be negative. However, the effects of catheter selection and negative pressure changes in the sheath on air intrusion are not yet well understood. The aim of this study was to evaluate how catheter selection and negative pressure changes affect air intrusion and to perform countermeasures for air intrusion., Methods and Results: This experiment used siphon principle to create negative pressure in the sheath. Noncryoablation catheters (not designed exclusively for cryoballoon ablation) and cryoballoon catheters were investigated. Catheters were inserted into the sheath and then removed. Thereafter, the amount of air in the sheath was measured. For catheters producing significantly larger amounts of air intrusion, the catheters were inserted via a long sheath in the sheath (sheath-in-sheath technique) and the same procedures were repeated. We found that the amount of air intrusion through most of the noncryoablation catheters was significantly larger than that through cryoablation catheters. An increase in the magnitude of negative pressure in the sheath resulted in a proportional increase in air intrusion, but the sheath-in-sheath technique significantly reduced air intrusion., Conclusion: The amount of air intrusion increased when using catheters with complicated tip shapes and thin outer diameters and when the magnitude of negative pressure in the sheath increased. The sheath-in-sheath technique may be an effective countermeasure., (© 2019 Wiley Periodicals, Inc.)
- Published
- 2019
- Full Text
- View/download PDF
48. Gertia stigmatica gen. et sp. nov. (Kareniaceae, Dinophyceae), a New Marine Unarmored Dinoflagellate Possessing the Peridinin-type Chloroplast with an Eyespot.
- Author
-
Takahashi K, Benico G, Lum WM, and Iwataki M
- Subjects
- Dinoflagellida cytology, Dinoflagellida metabolism, Species Specificity, Aquatic Organisms classification, Aquatic Organisms cytology, Aquatic Organisms metabolism, Carotenoids metabolism, Chloroplasts classification, Chloroplasts metabolism, Dinoflagellida classification
- Abstract
Marine unarmored dinoflagellates in the family Kareniaceae are known to possess chloroplasts of haptophyte origin, which contain fucoxanthin and its derivatives as major carotenoids, and lack peridinin. In the present study, the first species with the peridinin-type chloroplast in this family, Gertia stigmatica gen. et sp. nov., is described on the basis of ultrastructure, photosynthetic pigment composition, and molecular phylogeny inferred from nucleus- and chloroplast-encoded genes. Cells of G. stigmatica were small and harboring a chloroplast with an eyespot and two pyrenoids. The apical structure complex was straight, similar to Karenia and Karlodinium. Under transmission electron microscopy, the chloroplast was surrounded by two membranes, and the eyespot was composed of a single layer of osmiophilic globules (eyespot type A); this was never previously reported from the Kareniaceae. High performance liquid chromatography demonstrated the chloroplast contains peridinin, and neither fucoxanthin nor 19'-acyloxyfucoxanthins was identified. A phylogeny based on nucleus-encoded rDNAs suggested a position of G. stigmatica in the Kareniaceae, but not clustered within the previously described genera, i.e., Karenia, Karlodinium and Takayama. A phylogeny of chloroplast-encoded psbA, psbC and psbD indicated the chloroplast is of peridinin-type typical of dinoflagellates, but the most related species remains unclear., (Copyright © 2019 Elsevier GmbH. All rights reserved.)
- Published
- 2019
- Full Text
- View/download PDF
49. Insights into the mechanism of paradoxical low-flow, low-pressure gradient severe aortic stenosis: association with reduced O 2 consumption by the whole body.
- Author
-
Onoue T, Iwataki M, Araki M, Itoh H, Isotani A, Umeda H, Fukuda S, Nagata Y, Tsuda Y, Fujino Y, Hanyu M, Ando K, Shirai S, Takeuchi M, Saeki S, Levine RA, and Otsuji Y
- Subjects
- Aged, Aged, 80 and over, Aortic Valve Stenosis diagnostic imaging, Blood Pressure, Echocardiography, Doppler, Female, Heart Function Tests, Heart Valve Diseases diagnostic imaging, Heart Valve Diseases metabolism, Heart Valve Diseases physiopathology, Humans, Male, Retrospective Studies, Risk Factors, Stroke Volume, Aortic Valve Stenosis metabolism, Aortic Valve Stenosis physiopathology, Oxygen Consumption
- Abstract
The mechanism of reduced stroke volume index (SVi) in paradoxical low-flow, low-pressure gradient (PLFLPG) aortic stenosis (AS) remains unclarified. Guyton et al. ( 21 ) demonstrated that SVi is determined by whole body O
2 consumption (V̇o2 ) in many subjects, including patients with heart disease. We hypothesized that reduced SVi in PLFLPG AS is associated with reduced V̇o2 by the whole body. This study investigated the relationship between V̇o2 , SVi, and AS severity in patients with AS to examine the association between reduced V̇o2 and PLFLPG AS. In 59 patients (24 men and 35 women, mean age: 78 ± 7 yr old) with severe AS, SVi, AS severity, and type were evaluated by echocardiography, and V̇o2 was measured by the fraction of O2 in expired gases. SVi and V̇o2 were significantly decreased in 20 patients with PLFLPG AS compared with 39 patients with non-PLFLPG AS (30 ± 4 vs. 41 ± 7 ml/m2 and 2.4 ± 0.5 vs. 3.0 ± 0.5 ml·min-1 ·kg-1 , respectively, P < 0.01). The SVi-to-V̇o2 ratio was not different between the two groups (13.1 ± 2.6 vs. 13.6 ± 2.1, not significant). SVi was independently correlated with V̇o2 ( r = 0.74, P < 0.01) but not with the aortic valve area index. Categorized PLFLPG AS was also significantly associated with reduced V̇o2 ( P < 0.001). PLFLPG AS is associated with reduced V̇o2 by the whole body, which may offer insights into the mechanism of PLFLPG AS. NEW & NOTEWORTHY Paradoxical low-flow, low-pressure gradient severe aortic stenosis (PLFLPG AS) is an important and problematic subtype, and its central pathophysiology with reduced stroke volume is yet to be clarified. We hypothesized and subsequently clarified that reduced stroke volume in PLFLPG AS is associated with reduced O2 consumption by the whole body. This study suggests important insights into the mechanism of PLFLPG AS and may further promote studies to investigate further mechanisms and novel treatment.- Published
- 2019
- Full Text
- View/download PDF
50. Discovery of a New Clade Nested Within the Genus Alexandrium (Dinophyceae): Morpho-molecular Characterization of Centrodinium punctatum (Cleve) F.J.R. Taylor.
- Author
-
Li Z, Mertens KN, Nézan E, Chomérat N, Bilien G, Iwataki M, and Shin HH
- Subjects
- Alveolata cytology, Alveolata genetics, DNA, Protozoan genetics, Species Specificity, Alveolata classification, Phylogeny
- Abstract
Investigation of phytoplankton from East China Sea of the Pacific Ocean, offshore Réunion Island of the Indian Ocean, and the French Atlantic coast revealed a species of poorly known armored fusiform dinoflagellate. To clarify this species, morphology and phylogeny based on mitochondrial and nuclear protein gene sequence (Cox1, Cob and Hsp90) concatenated with the SSU, ITS region and LSU rDNA sequences were analysed. Epifluorescence and scanning electron microscopy observations revealed that the nucleus of the specimen was elongated, sausage-shaped and located equatorially on the left lateral side of the cell, and that the plate formula is Po, 3', 1a, 6″, 6C, 8S, 5‴, 1p, 2'‴. These morphological features indicate that the species can be assigned to Centrodinium punctatum. Interestingly, the phylogenetic analyses placed this species within the Alexandrium clade, with Alexandrium affine being its closest relative. This indicates that genus Alexandrium is not monophyletic. The most similar morphological traits between C. punctatum and Alexandrium species were the shape of apical pore plate and the arrangement of the sulcal plates. However, since there are significant morphological differences between C. punctatum and Alexandrium species, further studies are needed to clarify the relation between the morphology and molecular phylogeny of other Centrodinium-related fusiform species., (Copyright © 2019 Elsevier GmbH. All rights reserved.)
- Published
- 2019
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.