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Hiroshi Kurosawa - One of the best experts on this subject based on the ideXlab platform.
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methods for inducing embryoid body formation in vitro differentiation system of embryonic stem cells
Journal of Bioscience and Bioengineering, 2007Co-Authors: Hiroshi KurosawaAbstract:When cultured in suspension without antidifferentiation factors, embryonic stem (ES) cells spontaneously differentiate and form three-dimensional multicellular aggregates called embryoid bodies (EBs). EBs recapitulate many aspects of cell differentiation during early embryogenesis, and play an important role in the differentiation of ES cells into a variety of cell types in vitro. There are several methods for inducing the formation of EBs from ES cells. The three basic methods are liquid suspension culture in bacterial-grade dishes, culture in methylcellulose semisolid media, and culture in hanging drops. Recently, the methods using a round-bottomed 96-well plate and a Conical Tube are adopted for forming EBs from predetermined numbers of ES cells. For the production of large numbers of EBs, stirred-suspension culture using spinner flasks and bioreactors is performed. Each of these methods has its own peculiarity; thus, the features of formed EBs depending on the method used. Therefore, we should choose an appropriate method for EB formation according to the objective to be attained. In this review, we summarize the studies on in vitro differentiation of ES cells via EB formation and highlight the EB formation methods recently developed including the techniques, devices, and procedures involved.
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a simple method for forming embryoid body from mouse embryonic stem cells
Journal of Bioscience and Bioengineering, 2003Co-Authors: Hiroshi Kurosawa, Tetsuya Imamura, Mikiko Koike, Katsunori Sasaki, Yoshifumi AmanoAbstract:Abstract We proposed a simple method for forming an embryoid body (EB) from mouse embryonic stem (ES) cells using a polypropylene 1.5-ml Conical Tube with a screw cap. An ES cell suspension containing 2 × 10 4 cells was incubated in a Conical Tube. After 5 d of incubation, a single EB of 440 μm average diameter was formed in the Conical Tube. The formation efficiency of EB, which is the ratio of the number of Tubes showing EB formation to the number of Tubes seeded with ES cells, was greater than 99% in the Conical Tube, while it was approximately 60% in a hanging drop culture. The 5-day-old EB formed by the Conical Tube method had a sufficient differentiation ability. The beating of the cardiac muscle was microscopically observed in the populations derived from the 5-day-old EB.
Kotaro Yoshimura - One of the best experts on this subject based on the ideXlab platform.
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optimized preparation method of platelet concentrated plasma and noncoagulating platelet derived factor concentrates maximization of platelet concentration and removal of fibrinogen
Tissue Engineering Part C-methods, 2012Co-Authors: Jun Araki, Masahiro Jona, Harunosuke Kato, Hirotaka Suga, Yutaka Yatomi, Kotaro YoshimuraAbstract:Abstract Platelet-rich plasma (PRP) has been clinically used as an easily prepared growth factor cocktail that can promote wound healing, angiogenesis, and tissue remodeling. However, the therapeutic effects of PRP are still controversial, due partly to the lack of optimized and standardized preparation protocols. We used whole blood (WB) samples to optimize the preparation protocols for PRP, white blood cell-containing (W-PRP), platelet-concentrated plasma (PCP), and noncoagulating platelet-derived factor concentrate (PFC). PRP and W-PRP were most efficiently collected by 10 min centrifugation in a 15-mL Conical Tube at 230–270 g and 70 g, respectively. To prepare PCP, platelets were precipitated by centrifugation of PRP at >2300 g, 90% of supernatant plasma was removed, and the platelets were resuspended. For preparation of noncoagulating PFC, the supernatant was replaced with one-tenth volume of saline, followed by platelet activation with thrombin. Platelet (before activation) and platelet-derived gro...
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optimized preparation method of platelet concentrated plasma and noncoagulating platelet derived factor concentrates maximization of platelet concentration and removal of fibrinogen
Tissue Engineering Part C-methods, 2012Co-Authors: Ju Araki, Masahiro Jona, Harunosuke Kato, Hirotaka Suga, Yutaka Yatomi, Hitomi Eto, Noriyuki Aoi, Kentaro Doi, Kotaro YoshimuraAbstract:Platelet-rich plasma (PRP) has been clinically used as an easily prepared growth factor cocktail that can promote wound healing, angiogenesis, and tissue remodeling. However, the therapeutic effects of PRP are still controversial, due partly to the lack of optimized and standardized preparation protocols. We used whole blood (WB) samples to optimize the preparation protocols for PRP, white blood cell-containing (W-PRP), platelet-concentrated plasma (PCP), and noncoagulating platelet-derived factor concentrate (PFC). PRP and W-PRP were most efficiently collected by 10 min centrifugation in a 15-mL Conical Tube at 230-270 g and 70 g, respectively. To prepare PCP, platelets were precipitated by centrifugation of PRP at >2300 g, 90% of supernatant plasma was removed, and the platelets were resuspended. For preparation of noncoagulating PFC, the supernatant was replaced with one-tenth volume of saline, followed by platelet activation with thrombin. Platelet (before activation) and platelet-derived growth factor (PDGF)-BB (after activation) concentrations in PCP were approximately 20 times greater than those in WB, whereas PFC contained a 20-times greater concentration of platelets before platelet activation and a 50-times greater concentration of PDGF-BB without formation of a fibrin gel after platelet activation than WB. Surprisingly, total PDGF-BB content in the PFC was twice that of activated WB, which suggested that a substantial portion of the PDGF-BB became trapped in the fibrin glue, and replacement of plasma with saline is crucial for maximization of platelet-derived factors. As an anticoagulant, ethylene di-amine tetra-acetic acid disodium inhibited platelet aggregation more efficiently than acid citrate dextrose solution, resulting in higher nonaggregated platelet yield and final PDGF-BB content. These results increase our understanding of how to optimize and standardize preparation of platelet-derived factors at maximum concentrations.
James D Schiffbauer - One of the best experts on this subject based on the ideXlab platform.
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a cloudina like fossil with evidence of asexual reproduction from the lowest cambrian south china
Geological Magazine, 2017Co-Authors: Jian Han, James D Schiffbauer, Yaoping Cai, Hong Hua, Xing Wang, Xiaoguang Yang, Kentaro Uesugi, Tsuyoshi Komiya, Jie SunAbstract:The earliest fossil record of animal biomineralization occurs in the latest Ediacaran Period ( c . 550 Ma). Cloudina and Sinotubulites are two important tubular taxa among these earliest skeletal fossils. The evolutionary fate of Cloudina -type fossils across the Ediacaran–Cambrian transition, however, remains poorly understood. Here we report a multi-layered tubular microfossil Feiyanella manica gen. et sp. nov. from a phosphorite interval of the lowest Cambrian Kuanchuanpu Formation, southern Shaanxi Province, South China. This newly discovered fossil is a Conical Tube with a ‘funnel-in-funnel’ construction, showing profound morphological similarities to Cloudina and Conotubus . On the other hand, the outer few layers, and particularly the outermost layer, of Feiyanella Tubes are regularly to irregularly corrugated, a feature strikingly similar to the variably folded/wrinkled Tube walls of Sinotubulites . The Feiyanella Tubes additionally exhibit two orders of dichotomous branching, similar to branching structures reported occasionally in Cloudina and possibly indicative of asexual reproduction. Owing to broad similarities in Tube morphology, Tube wall construction and features presumably indicative of asexual reproduction, Cloudina, Conotubus, Sinotubulites and the here described Feiyanella may thus constitute a monophyletic group traversing the Ediacaran–Cambrian boundary. The Tube construction and palaeoecological strategy of Feiyanella putatively indicate evolutionary continuity in morphology and palaeoecology of benthic metazoan communities across the Ediacaran–Cambrian transition.
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taxonomy of the late ediacaran index fossil cloudina and a new similar taxon from south china
Precambrian Research, 2017Co-Authors: Yaoping Cai, James D Schiffbauer, Ivan Cortijo, Hong HuaAbstract:Abstract Cloudina is a late Ediacaran tubular fossil known from almost every continent. It is typically a mm- to cm-sized Conical Tube consisting of multiple, nested, funnel-shaped elements, forming the diagnostic “funnel-in-funnel” Tube construction. Although the morphology and paleoecology of Cloudina have been extensively reconstructed, a comprehensive morphological description, specifically to enable interspecific distinction, is yet lacking, primarily due to poor taphonomic resolution. Here we illustrate a number of interspecific variations of three-dimensionally preserved Cloudina fossils from the late Ediacaran Dengying Formation (southern Shaanxi Province, South China). A systematic re-evaluation of previously published Chinese Cloudina is documented: two published species (C. sinensis and C. lijiagouensis) are synonymized with the type species (C. hartmannae) and two new species (C. ningqiangensis n. sp. and C. xuanjiangpingensis n. sp.) are established. The type species and the two new species are distinguished by the location of transverse and/or oblique annulations occurring at different portions of the funnel. A new co-occurring Cloudina-like fossil, Multiconotubus chinensis gen. et sp. nov., with a “cone-in-cone” tubular construction is also reported and described in this study, and a detailed comparison is provided between these taxa. The revised taxonomy of Cloudina fossils not only adds to our knowledge of morphological disparity of these important organisms, but also helps to reconstruct their paleogeographic distribution and related paleoecological dynamics.
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morphology and paleoecology of the late ediacaran tubular fossil conotubus hemiannulatus from the gaojiashan lagerstatte of southern shaanxi province south china
Precambrian Research, 2011Co-Authors: James D Schiffbauer, Shuhai XiaoAbstract:a b s t r a c t Conotubus hemiannulatus Zhang and Lin 1986 is a phylogenetically problematic tubular fossil that is only known from the late Ediacaran (ca. 551-541 Ma) Gaojiashan Lagerstatte in southern Shaanxi Province, South China. It is a cm-sized Conical Tube that tapers adapically from an aperture to a rounded apex. The Tube consists of a series of nested cylindrical-to-funnel-shaped Tube walls (cylinders hereafter). This conotubular construction of nested cylinders is similar to that of the late Ediacaran fossil Cloudina. Integrated morphological, taphonomic, and paleoecological data suggest that C. hemiannulatus occu- pied an epibenthic life-mode, with the apex anchoring to muddy substrate and the aperture extending upwards into the water column. It was probably a suspension-feeding organism. This soft bottom dweller employed specialized paleoecological strategies to rejuvenate and self-right the Tubes after being sub- jected to sediment obrution, indicating strong burial-resistant capabilities. The Tube likely provided space for the living organism, with successively larger cylinders added episodically to accommodate growth. Currently available evidence suggests that C. hemiannulatus likely had non-biomineralized Tubes, and, although potentially closely related to Cloudina, its phylogenetic affinity remains unresolved. © 2011 Elsevier B.V. All rights reserved.
Margareth Lara Capurro - One of the best experts on this subject based on the ideXlab platform.
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glyTube a Conical Tube and parafilm m based method as a simplified device to artificially blood feed the dengue vector mosquito aedes aegypti
PLOS ONE, 2013Co-Authors: Andre Luis Costadasilva, Flávia Rosa Navarrete, Felipe Scassi Salvador, Rafaella Sayuri Ioshino, Diego Soares Azevedo, Desirée Rafaela Rocha, Camila Malta Romano, Maria Karinacosta, Margareth Lara CapurroAbstract:Aedes aegypti, the main vector of dengue virus, requires a blood meal to produce eggs. Although live animals are still the main blood source for laboratory colonies, many artificial feeders are available. These feeders are also the best method for experimental oral infection of Ae. aegypti with Dengue viruses. However, most of them are expensive or laborious to construct. Based on principle of Rutledge-type feeder, a conventional Conical Tube, glycerol and Parafilm-M were used to develop a simple in-house feeder device. The blood feeding efficiency of this apparatus was compared to a live blood source, mice, and no significant differences (p = 0.1189) were observed between artificial-fed (51.3% of engorgement) and mice-fed groups (40.6%). Thus, an easy to assemble and cost-effective artificial feeder, designated “GlyTube” was developed in this report. This simple and efficient feeding device can be built with common laboratory materials for research on Ae. aegypti.
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Materials used to assemble the GlyTube blood feeder device.
2013Co-Authors: André Luis Costa-da-silva, Flávia Rosa Navarrete, Felipe Scassi Salvador, Maria Karina-costa, Rafaella Sayuri Ioshino, Diego Soares Azevedo, Desirée Rafaela Rocha, Camila Malta Romano, Margareth Lara CapurroAbstract:A. A Conical Tube (50 mL) filled with 40 mL warmed 100% glycerol and top sealed with Dura Seal™ heat-resistant sealing film. The sealing film is laterally held to the Tube using a Parafilm-M® thin strip (2.5 cm×5.0 cm). B. Screw cap of the Conical Tube. Dashed circular black line indicates the cap region where plastic is removed by cutting to generate the feeding element. C. Screw cap with 2.5 cm diameter hole. D. Screw cap covered externally with stretched Parafilm-M. A strip of Parafilm is fixing the feeding membrane to the cap. E. A piece of Parafilm-M (5 cm×5 cm) as a feeding membrane. Parafilm must be stretched to cover the screw cap. F. A piece of Dura Seal heat-resistant sealing film is used to sealing the Conical Tube filled with pre-heated 100% glycerol. G. Blood supplying the feeding element at internal side of the screw cap with the stretched Parafilm membrane. H. Heating and feeding elements assembled together to feed the Ae. aegypti females. I. Non blood-fed (black arrowhead) and artificially blood-fed females with dilated abdomens (black arrows).
Yoshifumi Amano - One of the best experts on this subject based on the ideXlab platform.
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a simple method for forming embryoid body from mouse embryonic stem cells
Journal of Bioscience and Bioengineering, 2003Co-Authors: Hiroshi Kurosawa, Tetsuya Imamura, Mikiko Koike, Katsunori Sasaki, Yoshifumi AmanoAbstract:Abstract We proposed a simple method for forming an embryoid body (EB) from mouse embryonic stem (ES) cells using a polypropylene 1.5-ml Conical Tube with a screw cap. An ES cell suspension containing 2 × 10 4 cells was incubated in a Conical Tube. After 5 d of incubation, a single EB of 440 μm average diameter was formed in the Conical Tube. The formation efficiency of EB, which is the ratio of the number of Tubes showing EB formation to the number of Tubes seeded with ES cells, was greater than 99% in the Conical Tube, while it was approximately 60% in a hanging drop culture. The 5-day-old EB formed by the Conical Tube method had a sufficient differentiation ability. The beating of the cardiac muscle was microscopically observed in the populations derived from the 5-day-old EB.