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Offspring from Mouse Embryos Developed Using a Simple Incubator-Free Culture System with a Deoxidizing Agent
Fumiaki Itoi, Mikiko Tokoro, Yukari Terashita, Kazuo Yamagata, Noritaka Fukunaga, Yoshimasa Asada, Teruhiko Wakayama
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0047512
Abstract: To culture preimplantation embryos in vitro, water-jacketed CO2 incubators are used widely for maintaining an optimal culture environment in terms of gas phase, temperature and humidity. We investigated the possibility of mouse embryo culture in a plastic bag kept at 37°C. Zygotes derived from in vitro fertilization or collected from naturally mated B6D2F1 female mice were put in a drop of medium on a plastic culture dish and then placed in a commercially available plastic bag. When these were placed in an oven under air at 37°C for 96 h, the rate of blastocyst development and the cell numbers of embryos decreased. However, when the concentration of O2 was reduced to 5% using a deoxidizing agent and a small oxygen meter, most zygotes developed into blastocysts. These blastocysts were judged normal according to their cell number, Oct3/4 and Cdx2 gene expression levels, the apoptosis rate and the potential for full-term development after embryo transfer to pseudopregnant recipients. Furthermore, using this system, normal offspring were obtained simply by keeping the bag on a warming plate. This culture method was applied successfully to both hybrid and inbred strains. In addition, because the developing embryos could be observed through the transparent wall of the bag, it was possible to capture time-lapse images of live embryos until the blastocyst stage without needing an expensive microscope-based incubation chamber. These results suggest that mouse zygotes are more resilient to their environment than generally believed. This method might prove useful in economical culture systems or for the international shipment of embryos.
The current situation and issues there of related to nursing care at the time of medical examinations for children with developmental disabilities including autism  [PDF]
Mikiko Natsume
Open Journal of Nursing (OJN) , 2014, DOI: 10.4236/ojn.2014.41004

The objective of this study is to clarify the details regarding nursing care that is currently provided in terms of the situation regarding medical examinations for children with developmental disabilities and to discuss necessary nursing care. I conducted semi-structured interviews among 13 parents brining up children with developmental disabilities and analyzed the content of verbatim reports both qualitatively and functionally. Regarding those situations when they feel difficult at the time of undergoing medical examinations at the medical institute, the following four categories were extracted: painful treatment; difficulty in predicting; difficulty in communicating; and trouble in the waiting room. Regarding nursing care felt necessary at the time of undergoing medical examinations, the following six categories were extracted: technique while suppressing pain to a minimum; involvement in providing perspective; adjustment of surrounding environment; provision of opportunities to get acclimatized; provision of warm support; and understanding of patient characteristics. Many difficulties regarding medical examinations were revealed and it was found that they have concerns with regard to health management. It has been suggested that it is important to adjust the surrounding environment during medical examinations.

Problems and Instruction Needed in Relation to Nursing Students’ Handling of Patient Information—From a Survey of Nurses Coordinating Clinical Practicums in Japan  [PDF]
Mikiko Natsume
Open Journal of Nursing (OJN) , 2018, DOI: 10.4236/ojn.2018.83019
The purpose of this study was to clarify and consider the instruction that is needed in relation to nursing students’ handling of patient information, as felt by the people in charge of student clinical practicums in hospitals. Semi-structured interviews were conducted with 7 people in charge of organizing practicums at hospitals where they are carried out. These subjects were asked about problems they had experienced in relation to nursing students’ handling of patient information and the instruction that is needed so that problems related to nursing students’ handling of information do not occur. Various problems were shown to occur in relation to nursing students’ handling of patient information, such as handling the information outside of the practicum setting. Many students receive no instruction with regard to the ethics of handling patient information in their classroom work, and their awareness regarding information is cannot be considered high, indicating the need for more consistent and reliable education in this area. The findings also suggest that instruction is needed with regard to the handling of sensitive information in accordance with the circumstances of individual patients.
Latrunculin A Treatment Prevents Abnormal Chromosome Segregation for Successful Development of Cloned Embryos
Yukari Terashita, Kazuo Yamagata, Mikiko Tokoro, Fumiaki Itoi, Sayaka Wakayama, Chong Li, Eimei Sato, Kentaro Tanemura, Teruhiko Wakayama
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0078380
Abstract: Somatic cell nuclear transfer to an enucleated oocyte is used for reprogramming somatic cells with the aim of achieving totipotency, but most cloned embryos die in the uterus after transfer. While modifying epigenetic states of cloned embryos can improve their development, the production rate of cloned embryos can also be enhanced by changing other factors. It has already been shown that abnormal chromosome segregation (ACS) is a major cause of the developmental failure of cloned embryos and that Latrunculin A (LatA), an actin polymerization inhibitor, improves F-actin formation and birth rate of cloned embryos. Since F-actin is important for chromosome congression in embryos, here we examined the relation between ACS and F-actin in cloned embryos. Using LatA treatment, the occurrence of ACS decreased significantly whereas cloned embryo-specific epigenetic abnormalities such as dimethylation of histone H3 at lysine 9 (H3K9me2) could not be corrected. In contrast, when H3K9me2 was normalized using the G9a histone methyltransferase inhibitor BIX-01294, the Magea2 gene—essential for normal development but never before expressed in cloned embryos—was expressed. However, this did not increase the cloning success rate. Thus, non-epigenetic factors also play an important role in determining the efficiency of mouse cloning.
GSE Is a Maternal Factor Involved in Active DNA Demethylation in Zygotes
Yuki Hatanaka, Natsumi Shimizu, Satoshi Nishikawa, Mikiko Tokoro, Seung-Wook Shin, Takuji Nishihara, Tomoko Amano, Masayuki Anzai, Hiromi Kato, Tasuku Mitani, Yoshihiko Hosoi, Satoshi Kishigami, Kazuya Matsumoto
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0060205
Abstract: After fertilization, the sperm and oocyte genomes undergo extensive epigenetic reprogramming to form a totipotent zygote. The dynamic epigenetic changes during early embryo development primarily involve DNA methylation and demethylation. We have previously identified Gse (gonad-specific expression gene) to be expressed specifically in germ cells and early embryos. Its encoded protein GSE is predominantly localized in the nuclei of cells from the zygote to blastocyst stages, suggesting possible roles in the epigenetic changes occurring during early embryo development. Here, we report the involvement of GSE in epigenetic reprogramming of the paternal genome during mouse zygote development. Preferential binding of GSE to the paternal chromatin was observed from pronuclear stage 2 (PN2) onward. A knockdown of GSE by antisense RNA in oocytes produced no apparent effect on the first and second cell cycles in preimplantation embryos, but caused a significant reduction in the loss of 5-methylcytosine (5 mC) and the accumulation of 5-hydroxymethylcytosine (5 hmC) in the paternal pronucleus. Furthermore, DNA methylation levels in CpG sites of LINE1 transposable elements, Lemd1, Nanog and the upstream regulatory region of the Oct4 (also known as Pou5f1) gene were clearly increased in GSE-knockdown zygotes at mid-pronuclear stages (PN3-4), but the imprinted H19-differential methylated region was not affected. Importantly, DNA immunoprecipitation of 5 mC and 5 hmC also indicates that knockdown of GSE in zygotes resulted in a significant reduction of the conversion of 5 mC to 5 hmC on LINE1. Therefore, our results suggest an important role of maternal GSE for mediating active DNA demethylation in the zygote.
A comparative study of the polarographic behavior of cobalt(II), nickel(II), manganese(II), and zinc(II) in azide solutions
Giovedi, Claudia;Tokoro, Roberto;
Journal of the Brazilian Chemical Society , 1997, DOI: 10.1590/S0103-50531997000200018
Abstract: the electrochemical behavior of cobalt(ii), nickel(ii), manganese(ii), and zinc(ii) was studied by polarography at several azide concentrations. the reduction waves of cobalt(ii) and nickel(ii) exhibit a shift of the potential towards more positive values, with the increasing ligand concentration in solution. the maximum anticipation observed is 300 mv for cobalt(ii) and 370 mv for nickel(ii). in the case of zinc(ii), an anticipation of only 27 mv is observed at low ligand concentrations, and for subsequent additions of ligand the reduction wave shifts towards more negative potentials. the behavior of manganese(ii) is different, as the reduction wave only shifts towards more negative potentials.
Gender-Specific Hierarchy in Nuage Localization of PIWI-Interacting RNA Factors in Drosophila
Mikiko C. Siomi
Frontiers in Genetics , 2011, DOI: 10.3389/fgene.2011.00055
Abstract: PIWI-interacting RNAs (piRNAs) are germline-specific small non-coding RNAs that form piRNA-induced silencing complexes (piRISCs) by associating with PIWI proteins, a subclade of the Argonaute proteins predominantly expressed in the germline. piRISCs protect the integrity of the germline genome from invasive transposable DNA elements by silencing them. Multiple piRNA biogenesis factors have been identified in Drosophila. The majority of piRNA factors are localized in the nuage, electron-dense non-membranous cytoplasmic structures located in the perinuclear regions of germ cells. Thus, piRNA biogenesis is thought to occur in the nuage in germ cells. Immunofluorescence analyses of ovaries from piRNA factor mutants have revealed a localization hierarchy of piRNA factors in female nuage. However, whether this hierarchy is female-specific or can also be applied in male gonads remains undetermined. Here, we show by immunostaining of both ovaries and testes from piRNA factor mutants that the molecular hierarchy of piRNA factors shows gender-specificity, especially for Krimper (Krimp), a Tudor-domain-containing protein of unknown function(s): Krimp is dispensable for PIWI protein Aubergine (Aub) nuage localization in ovaries but Krimp and Aub require each other for their proper nuage localization in testes. This suggests that the functional requirement of Krimp in piRNA biogenesis may be different in male and female gonads.
A história, evolu??o e crescimento da Eletroquímica: Eletroanalítica nestes últimos 25 anos
Avaca, Luis Alberto;Tokoro, Roberto;
Química Nova , 2002, DOI: 10.1590/S0100-40422002000800005
Abstract: this text describes the development of electrochemistry and electroanalytical chemistry in brazil from the pioneers at the iq/usp in the 70's to the present day status. it explains how the members of the scientific community organized themselves before the establishment in 1993 of a specific division within the brazilian chemical society (sbq) through bi-ennial meetings (brazilian symposium of electrochemistry and electroanalytical chemistry - sibee). those sibee meetings, in a present number of 12, are described individually giving some emphasis on their organizers, the invited speakers and the statistics and overall structure of the event. the activities of the electrochemistry and electroanalytical chemistry division of the sbq from 1993 are also briefly discussed as well as some considerations are made on the present and future of these fields.
A história, evolu o e crescimento da Eletroquímica: Eletroanalítica nestes últimos 25 anos
Avaca Luis Alberto,Tokoro Roberto
Química Nova , 2002,
Abstract: This text describes the development of Electrochemistry and Electroanalytical Chemistry in Brazil from the pioneers at the IQ/USP in the 70's to the present day status. It explains how the members of the scientific community organized themselves before the establishment in 1993 of a specific division within the Brazilian Chemical Society (SBQ) through bi-ennial meetings (Brazilian Symposium of Electrochemistry and Electroanalytical Chemistry - SIBEE). Those SIBEE meetings, in a present number of 12, are described individually giving some emphasis on their organizers, the invited speakers and the statistics and overall structure of the event. The activities of the Electrochemistry and Electroanalytical Chemistry Division of the SBQ from 1993 are also briefly discussed as well as some considerations are made on the present and future of these fields.
Molecular Cloning of cDNAs Encoding the Proteolipid Subunit of the Vacuolar H+-ATPase of Acetabularia acetabulum
M. Habibur Rahman,Mikiko Ikeda
Pakistan Journal of Biological Sciences , 2002,
Abstract: Three cDNAs (named pVC1, pVC2 and pVC3) have been isolated from a giant alga, Acetabularia acetabulum that encoded the N, N′- icyclohexylcarbodimide-binding 16 kDa proteolipid subunit of V-ATPase. The open reading frames of pVC1, pVC2 and pVC3 predicted the polypeptides of 164, 167 and 168 amino acids with the molecular masses of 16.5, 16.7 and 16.8 kDa, respectively. Seventy nine percent identity between pVC1 and pVC2 or pVC3 and 95% identity between pVC2 and pVC3 was observed. PVC1 and pVC2/pVC3 showed extensive divergences in their 3′ -untranslated region, while pVC2 and pVC3 possessed the same 3′ -untranslated region. The deduced amino acid sequences of the three cDNA clones showed extensive similarities with that of proteolipids of oat (75 to 80%), bovine (55%) and yeast (55%) V-ATPase. Based on hydropathy plot, four membrane-spanning domains were predicted, in which domain IV was especially conserved among different species. This domain showed 96-100% identity in amino acid sequences between the A. acetabulum and the oat proteolipid in which a glutamate residue is included, the putative N, N′-dicyclohexylcarbodimide-binding residue.
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