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Sample records for interspecies nuclear transfer

  1. Two-staged nuclear transfer can enhance the developmental ability of goat-sheep interspecies nuclear transfer embryos in vitro.

    PubMed

    Ma, Li-Bing; Cai, Lu; Li, Jia-Jia; Chen, Xiu-Li; Ji, Feng-Yu

    2011-02-01

    The technique of interspecies somatic cell nuclear transfer, in which interspecies cloned embryos can be reconstructed by using domestic animal oocytes as nuclear recipients and endangered animal or human somatic cells as nuclear donors, can afford more opportunities in endangered animal rescue and human tissue transplantation, but the application of this technique is limited by extremely low efficiency which may be attributed to donor nucleus not fully reprogrammed by xenogenic cytoplasm. In this study, goat fetal fibroblasts (GFFs) were used as nuclear donors, in vitro-matured sheep oocytes were used as nuclear recipients, and a two-stage nuclear transfer procedure was performed to improve the developmental ability of goat-sheep interspecies clone embryos. In the first stage nuclear transfer (FSNT), GFFs were injected into the ooplasm of enucleated sheep metaphase-II oocytes, then non-activated reconstructed embryos were cultured in vitro, so that the donor nucleus could be exposed to the ooplasm for a period of time. Subsequently, in the second stage nuclear transfer, FSNT-derived non-activated reconstructed embryo was centrifuged, and the donor nucleus was then transferred into another freshly enucleated sheep oocyte. Compared with the one-stage nuclear transfer, two-stage nuclear transfer could significantly enhance the blastocyst rate of goat-sheep interspecies clone embryos, and this result indicated that longtime exposure to xenogenic ooplasm benefits the donor nucleus to be reprogrammed. The two-stage nuclear transfer procedure has two advantages, one is that the donor nucleus can be exposed to the ooplasm for a long time, the other is that the problem of oocyte aging can be solved. PMID:21082282

  2. Successful cloning of coyotes through interspecies somatic cell nuclear transfer using domestic dog oocytes.

    PubMed

    Hwang, Insung; Jeong, Yeon Woo; Kim, Joung Joo; Lee, Hyo Jeong; Kang, Mina; Park, Kang Bae; Park, Jung Hwan; Kim, Yeun Wook; Kim, Woo Tae; Shin, Taeyoung; Hyun, Sang Hwan; Jeung, Eui-Bae; Hwang, Woo Suk

    2013-01-01

    Interspecies somatic cell nuclear transfer (iSCNT) is an emerging assisted reproductive technology (ART) for preserving Nature's diversity. The scarcity of oocytes from some species makes utilisation of readily available oocytes inevitable. In the present study, we describe the successful cloning of coyotes (Canis latrans) through iSCNT using oocytes from domestic dogs (Canis lupus familiaris or dingo). Transfer of 320 interspecies-reconstructed embryos into 22 domestic dog recipients resulted in six pregnancies, from which eight viable offspring were delivered. Fusion rate and cloning efficiency during iSCNT cloning of coyotes were not significantly different from those observed during intraspecies cloning of domestic dogs. Using neonatal fibroblasts as donor cells significantly improved the cloning efficiency compared with cloning using adult fibroblast donor cells (P<0.05). The use of domestic dog oocytes in the cloning of coyotes in the present study holds promise for cloning other endangered species in the Canidae family using similar techniques. However, there are still limitations of the iSCNT technology, as demonstrated by births of morphologically abnormal coyotes and the clones' inheritance of maternal domestic dog mitochondrial DNA. PMID:23217630

  3. Function of donor cell centrosome in intraspecies and interspecies nuclear transfer embryos

    SciTech Connect

    Zhong Zhisheng; Zhang Gang; Meng Xiaoqian; Zhang Yanling; Chen Dayuan; Schatten, Heide; Sun Qingyuan . E-mail: sunqy1@yahoo.com

    2005-05-15

    Centrosomes, the main microtubule-organizing centers (MTOCs) in most animal cells, are important for many cellular activities such as assembly of the mitotic spindle, establishment of cell polarity, and cell movement. In nuclear transfer (NT), MTOCs that are located at the poles of the meiotic spindle are removed from the recipient oocyte, while the centrosome of the donor cell is introduced. We used mouse MII oocytes as recipients, mouse fibroblasts, rat fibroblasts, or pig granulosa cells as donor cells to construct intraspecies and interspecies nuclear transfer embryos in order to observe centrosome dynamics and functions. Three antibodies against centrin, {gamma}-tubulin, and NuMA, respectively, were used to stain the centrosome. Centrin was not detected either at the poles of transient spindles or at the poles of first mitotic spindles. {gamma}-tubulin translocated into the two poles of the transient spindles, while no accumulated {gamma}-tubulin aggregates were detected in the area adjacent to the two pseudo-pronuclei. At first mitotic metaphase, {gamma}-tubulin was translocated to the spindle poles. The distribution of {gamma}-tubulin was similar in mouse intraspecies and rat-mouse interspecies embryos. The NuMA antibody that we used can recognize porcine but not murine NuMA protein, so it was used to trace the NuMA protein of donor cell in reconstructed embryos. In the pig-mouse interspecies reconstructed embryos, NuMA concentrated between the disarrayed chromosomes soon after activation and translocated to the transient spindle poles. NuMA then immigrated into pseudo-pronuclei. After pseudo-pronuclear envelope breakdown, NuMA was located between the chromosomes and then translocated to the spindle poles of first mitotic metaphase. {gamma}-tubulin antibody microinjection resulted in spindle disorganization and retardation of the first cell division. NuMA antibody microinjection also resulted in spindle disorganization. Our findings indicate that (1) the

  4. Reprogrammed Transcriptome in Rhesus-Bovine Interspecies Somatic Cell Nuclear Transfer Embryos

    PubMed Central

    Wang, Kai; Otu, Hasan H.; Chen, Ying; Lee, Young; Latham, Keith; Cibelli, Jose B.

    2011-01-01

    Background Global activation of the embryonic genome (EGA), one of the most critical steps in early mammalian embryo development, is recognized as the time when interspecies somatic cell nuclear transfer (iSCNT) embryos fail to thrive. Methodology/Principal Findings In this study, we analyzed the EGA-related transcriptome of rhesus-bovine iSCNT 8- to 16-cell embryos and dissected the reprogramming process in terms of embryonic gene activation, somatic gene silencing, and maternal RNA degradation. Compared with fibroblast donor cells, two thousand and seven genes were activated in iSCNT embryos, one quarter of them reaching expression levels comparable to those found in in vitro fertilized (IVF) rhesus embryos. This suggested that EGA in iSCNT embryos had partially recapitulated rhesus embryonic development. Eight hundred and sixty somatic genes were not silenced properly and continued to be expressed in iSCNT embryos, which indicated incomplete nuclear reprogramming. We compared maternal RNA degradation in bovine oocytes between bovine-bovine SCNT and iSCNT embryos. While maternal RNA degradation occurred in both SCNT and iSCNT embryos, we saw more limited overall degradation of maternal RNA in iSCNT embryos than in SCNT embryos. Several important maternal RNAs, like GPF9, were not properly processed in SCNT embryos. Conclusions/Significance Our data suggested that iSCNT embryos are capable of triggering EGA, while a portion of somatic cell-associated genes maintain their expression. Maternal RNA degradation seems to be impaired in iSCNT embryos. Further understanding of the biological roles of these genes, networks, and pathways revealed by iSCNT may expand our knowledge about cell reprogramming, pluripotency, and differentiation. PMID:21799794

  5. Production of rhesus monkey cloned embryos expressing monomeric red fluorescent protein by interspecies somatic cell nuclear transfer

    SciTech Connect

    Zhu, Hai-Ying; Kang, Jin-Dan; Li, Suo; Jin, Jun-Xue; Hong, Yu; Jin, Long; Guo, Qing; Gao, Qing-Shan; Yan, Chang-Guo; Yin, Xi-Jun

    2014-02-21

    Highlights: • Rhesus monkey cells were electroporated with a plasmid containing mRFP1, and an mRFP1-expressing cell line was generated. • For the first time, mRFP1-expressing rhesus monkey cells were used as donor cells for iSCNT. • The effect of VPA on the development of embryos cloned using iSCNT was determined. - Abstract: Interspecies somatic cell nuclear transfer (iSCNT) is a promising method to clone endangered animals from which oocytes are difficult to obtain. Monomeric red fluorescent protein 1 (mRFP1) is an excellent selection marker for transgenically modified cloned embryos during somatic cell nuclear transfer (SCNT). In this study, mRFP-expressing rhesus monkey cells or porcine cells were transferred into enucleated porcine oocytes to generate iSCNT and SCNT embryos, respectively. The development of these embryos was studied in vitro. The percentage of embryos that underwent cleavage did not significantly differ between iSCNT and SCNT embryos (P > 0.05; 71.53% vs. 80.30%). However, significantly fewer iSCNT embryos than SCNT embryos reached the blastocyst stage (2.04% vs. 10.19%, P < 0.05). Valproic acid was used in an attempt to increase the percentage of iSCNT embryos that developed to the blastocyst stage. However, the percentages of embryos that underwent cleavage and reached the blastocyst stage were similar between untreated iSCNT embryos and iSCNT embryos treated with 2 mM valproic acid for 24 h (72.12% vs. 70.83% and 2.67% vs. 2.35%, respectively). These data suggest that porcine-rhesus monkey interspecies embryos can be generated that efficiently express mRFP1. However, a significantly lower proportion of iSCNT embryos than SCNT embryos reach the blastocyst stage. Valproic acid does not increase the percentage of porcine-rhesus monkey iSCNT embryos that reach the blastocyst stage. The mechanisms underling nuclear reprogramming and epigenetic modifications in iSCNT need to be investigated further.

  6. Full-term development of gaur-bovine interspecies somatic cell nuclear transfer embryos: effect of trichostatin A treatment.

    PubMed

    Srirattana, Kanokwan; Imsoonthornruksa, Sumeth; Laowtammathron, Chuti; Sangmalee, Anawat; Tunwattana, Wanchai; Thongprapai, Thamnoon; Chaimongkol, Chockchai; Ketudat-Cairns, Mariena; Parnpai, Rangsun

    2012-06-01

    Trichostatin A (TSA) has previously been used in somatic cell nuclear transfer (SCNT) to improve the cloning efficiency in several species, which led our team to investigate the effects of TSA on the full-term development of bovine SCNT and gaur-bovine interspecies SCNT (gaur iSCNT; gaur somatic cells as donors and bovine oocytes as recipients) embryos. Treatment with 50 nM TSA for 10 h after fusion had no positive effects on the rates of fusion, cleavage, or the development to eight-cell or morula stages in both bovine SCNT and gaur iSCNT embryos. However, TSA treatment significantly enhanced the blastocyst formation rate in bovine SCNT embryos (44 vs. 32-34% in the TSA-treated and TSA-untreated groups, respectively), but had no effects on gaur iSCNT embryos. The fresh blastocysts derived from bovine SCNT and gaur iSCNT embryos (fresh groups), as well as vitrified bovine SCNT blastocysts (vitrified group), were transferred to bovine recipients. We found that TSA treatment increased the pregnancy rates only in recipients receiving fresh bovine SCNT embryos. In recipients receiving TSA-treated bovine SCNT embryos, three cloned calves from the fresh group and twin cloned calves from the vitrified group were delivered; however, no calf was born from the TSA-untreated bovine SCNT embryos. In contrast, one gaur iSCNT calf was born from a recipient receiving blastocysts from the TSA-untreated group. In summary, TSA improved the preimplantation development and pregnancy rates of bovine SCNT embryos, but did not have any beneficial effect on gaur iSCNT embryos. However, one gaur iSCNT calf reached full-term development. PMID:22578161

  7. Absence of nucleolus formation in raccoon dog-porcine interspecies somatic cell nuclear transfer embryos results in embryonic developmental failure.

    PubMed

    Jeon, Yubyeol; Nam, Yeong-Hee; Cheong, Seung-A; Kwak, Seong-Sung; Lee, Eunsong; Hyun, Sang-Hwan

    2016-08-25

    Interspecies somatic cell nuclear transfer (iSCNT) can be a solution for preservation of endangered species that have limited oocytes. It has been reported that blastocyst production by iSCNT is successful even if the genetic distances between donors and recipients are large. In particular, domestic pig oocytes can support the development of canine to porcine iSCNT embryos. Therefore, we examined whether porcine oocytes may be suitable recipient oocytes for Korean raccoon dog iSCNT. We investigated the effects of trichostatin A (TSA) treatment on iSCNT embryo developmental patterns and nucleolus formation. Enucleated porcine oocytes were fused with raccoon dog fibroblasts by electrofusion and cleavage, and blastocyst development and nucleolus formation were evaluated. To our knowledge, this study is the first in which raccoon dog iSCNT was performed using porcine oocytes; we found that 68.5% of 158 iSCNT embryos had the ability to cleave. However, these iSCNT embryos did not develop past the 4-cell stage. Treatment with TSA did not affect iSCNT embryonic development; moreover, the nuclei failed to form nucleoli at 48 and 72 h post-activation (hpa). In contrast, pig SCNT embryos of the control group showed 18.8% and 87.9% nucleolus formation at 48 and 72 hpa, respectively. Our results demonstrated that porcine cytoplasts efficiently supported the development of raccoon dog iSCNT embryos to the 4-cell stage, the stage of porcine embryonic genome activation (EGA); however, these embryos failed to reach the blastocyst stage and showed defects in nucleolus formation. PMID:27064112

  8. Absence of nucleolus formation in raccoon dog-porcine interspecies somatic cell nuclear transfer embryos results in embryonic developmental failure

    PubMed Central

    JEON, Yubyeol; NAM, Yeong-Hee; CHEONG, Seung-A; KWAK, Seong-Sung; LEE, Eunsong; HYUN, Sang-Hwan

    2016-01-01

    Interspecies somatic cell nuclear transfer (iSCNT) can be a solution for preservation of endangered species that have limited oocytes. It has been reported that blastocyst production by iSCNT is successful even if the genetic distances between donors and recipients are large. In particular, domestic pig oocytes can support the development of canine to porcine iSCNT embryos. Therefore, we examined whether porcine oocytes may be suitable recipient oocytes for Korean raccoon dog iSCNT. We investigated the effects of trichostatin A (TSA) treatment on iSCNT embryo developmental patterns and nucleolus formation. Enucleated porcine oocytes were fused with raccoon dog fibroblasts by electrofusion and cleavage, and blastocyst development and nucleolus formation were evaluated. To our knowledge, this study is the first in which raccoon dog iSCNT was performed using porcine oocytes; we found that 68.5% of 158 iSCNT embryos had the ability to cleave. However, these iSCNT embryos did not develop past the 4-cell stage. Treatment with TSA did not affect iSCNT embryonic development; moreover, the nuclei failed to form nucleoli at 48 and 72 h post-activation (hpa). In contrast, pig SCNT embryos of the control group showed 18.8% and 87.9% nucleolus formation at 48 and 72 hpa, respectively. Our results demonstrated that porcine cytoplasts efficiently supported the development of raccoon dog iSCNT embryos to the 4-cell stage, the stage of porcine embryonic genome activation (EGA); however, these embryos failed to reach the blastocyst stage and showed defects in nucleolus formation. PMID:27064112

  9. Interspecies nuclear transfer using fibroblasts from leopard, tiger, and lion ear piece collected postmortem as donor cells and rabbit oocytes as recipients.

    PubMed

    Yelisetti, Uma Mahesh; Komjeti, Suman; Katari, Venu Charan; Sisinthy, Shivaji; Brahmasani, Sambasiva Rao

    2016-06-01

    Skin fibroblast cells were obtained from a small piece of an ear of leopard, lion, and tiger collected postmortem and attempts were made to synchronize the skin fibroblasts at G0/G1 of cell cycle using three different approaches. Efficiency of the approaches was tested following interspecies nuclear transfer with rabbit oocytes as recipient cytoplasm. Fluorescence-activated cell sorting revealed that the proportion of G0/G1 cells increased significantly (P < 0.05) when cells subjected to serum starvation, contact inhibition, and 3 mM sodium butyrate (NaBu) treatment when compared with cycling cells. However, 3 mM NaBu treatment caused alterations in cell morphology and increase in dead cells. Thus, interspecies nuclear transfer was carried out using fibroblast cells subjected to contact inhibition for 72 h, serum starvation for 48 h, and cells treated with 1.0 mM NaBu for 48 h. The fusion rates, the proportion of fused couplets that cleaved to two-cell and developed to blastocyst, were highest in all three species when the donor cells were treated with 1.0 mM NaBu for 48 h. But, the blastocyst percentage of interspecies nuclear embryos (5-6%) was significantly lower when compared with rabbit-rabbit nuclear transfer embryos (22.9%). In conclusion, fibroblast cells of leopard, lion, and tiger were successfully synchronized and used for the development of blastocysts using rabbit oocytes as recipient cytoplasm. PMID:27071624

  10. Embryo aggregation does not improve the development of interspecies somatic cell nuclear transfer embryos in the horse.

    PubMed

    Gambini, Andrés; De Stéfano, Adrián; Jarazo, Javier; Buemo, Carla; Karlanian, Florencia; Salamone, Daniel Felipe

    2016-09-01

    The low efficiency of interspecies somatic cell nuclear transfer (iSCNT) makes it necessary to investigate new strategies to improve embryonic developmental competence. Embryo aggregation has been successfully applied to improve cloning efficiency in mammals, but it remains unclear whether it could also be beneficial for iSCNT. In this study, we first compared the effect of embryo aggregation over in vitro development and blastocyst quality of porcine, bovine, and feline zona-free (ZF) parthenogenetic (PA) embryos to test the effects of embryo aggregation on species that were later used as enucleated oocytes donors in our iSCNT study. We then assessed whether embryo aggregation could improve the in vitro development of ZF equine iSCNT embryos after reconstruction with porcine, bovine, and feline ooplasm. Bovine- and porcine-aggregated PA blastocysts had significantly larger diameters compared with nonaggregated embryos. On the other hand, feline- and bovine-aggregated PA embryos had higher blastocyst cell number. Embryo aggregation of equine-equine SCNT was found to be beneficial for embryo development as we have previously reported, but the aggregation of three ZF reconstructed embryos did not improve embryo developmental rates on iSCNT. In vitro embryo development of nonaggregated iSCNT was predominantly arrested around the stage when transcriptional activation of the embryonic genome is reported to start on the embryo of the donor species. Nevertheless, independent of embryo aggregation, equine blastocyst-like structures could be obtained in our study using domestic feline-enucleated oocytes. Taken together, these results reported that embryo aggregation enhance in vitro PA embryo development and embryo quality but effects vary depending on the species. Embryo aggregation also improves, as expected, the in vitro embryo development of equine-equine SCNT embryos; however, we did not observe positive effects on equine iSCNT embryo development. Among oocytes

  11. Promoting Interspecies Electron Transfer with Biochar

    PubMed Central

    Chen, Shanshan; Rotaru, Amelia-Elena; Shrestha, Pravin Malla; Malvankar, Nikhil S.; Liu, Fanghua; Fan, Wei; Nevin, Kelly P.; Lovley, Derek R.

    2014-01-01

    Biochar, a charcoal-like product of the incomplete combustion of organic materials, is an increasingly popular soil amendment designed to improve soil fertility. We investigated the possibility that biochar could promote direct interspecies electron transfer (DIET) in a manner similar to that previously reported for granular activated carbon (GAC). Although the biochars investigated were 1000 times less conductive than GAC, they stimulated DIET in co-cultures of Geobacter metallireducens with Geobacter sulfurreducens or Methanosarcina barkeri in which ethanol was the electron donor. Cells were attached to the biochar, yet not in close contact, suggesting that electrons were likely conducted through the biochar, rather than biological electrical connections. The finding that biochar can stimulate DIET may be an important consideration when amending soils with biochar and can help explain why biochar may enhance methane production from organic wastes under anaerobic conditions. PMID:24846283

  12. Plugging in or going wireless: strategies for interspecies electron transfer

    PubMed Central

    Shrestha, Pravin Malla; Rotaru, Amelia-Elena

    2014-01-01

    Interspecies exchange of electrons enables a diversity of microbial communities to gain energy from reactions that no one microbe can catalyze. The first recognized strategies for interspecies electron transfer were those that relied on chemical intermediates that are recycled through oxidized and reduced forms. Well-studied examples are interspecies H2 transfer and the cycling of sulfur intermediates in anaerobic photosynthetic communities. Direct interspecies electron transfer (DIET) in which two species establish electrical contact is an alternative. Electrical contacts documented to date include electrically conductive pili, as well as conductive iron minerals and conductive carbon moieties such as activated carbon and biochar. Interspecies electron transfer is central to the functioning of methane-producing microbial communities. The importance of interspecies H2 transfer in many methanogenic communities is clear, but under some circumstances DIET predominates. It is expected that further mechanistic studies and broadening investigations to a wider range of environments will help elucidate the factors that favor specific forms of interspecies electron exchange under different environmental conditions. PMID:24904551

  13. Hardwiring microbes via direct interspecies electron transfer: mechanisms and applications.

    PubMed

    Cheng, Qiwen; Call, Douglas F

    2016-08-10

    Multicellular microbial communities are important catalysts in engineered systems designed to treat wastewater, remediate contaminated sediments, and produce energy from biomass. Understanding the interspecies interactions within them is therefore essential to design effective processes. The flow of electrons within these communities is especially important in the determination of reaction possibilities (thermodynamics) and rates (kinetics). Conventional models of electron transfer incorporate the diffusion of metabolites generated by one organism and consumed by a second, frequently referred to as mediated interspecies electron transfer (MIET). Evidence has emerged in the last decade that another method, called direct interspecies electron transfer (DIET), may occur between organisms or in conjunction with electrically conductive materials. Recent research has suggested that DIET can be stimulated in engineered systems to improve desired treatment goals and energy recovery in systems such as anaerobic digesters and microbial electrochemical technologies. In this review, we summarize the latest understanding of DIET mechanisms, the associated microorganisms, and the underlying thermodynamics. We also critically examine approaches to stimulate DIET in engineered systems and assess their effectiveness. We find that in most cases attempts to promote DIET in mixed culture systems do not yield the improvements expected based on defined culture studies. Uncertainties of other processes that may be co-occurring in real systems, such as contaminant sorption and biofilm promotion, need to be further investigated. We conclude by identifying areas of future research related to DIET and its application in biological treatment processes. PMID:27349520

  14. Syntrophic growth via quinone-mediated interspecies electron transfer

    PubMed Central

    Smith, Jessica A.; Nevin, Kelly P.; Lovley, Derek R.

    2015-01-01

    The mechanisms by which microbial species exchange electrons are of interest because interspecies electron transfer can expand the metabolic capabilities of microbial communities. Previous studies with the humic substance analog anthraquinone-2,6-disulfonate (AQDS) suggested that quinone-mediated interspecies electron transfer (QUIET) is feasible, but it was not determined if sufficient energy is available from QUIET to support the growth of both species. Furthermore, there have been no previous studies on the mechanisms for the oxidation of anthrahydroquinone-2,6-disulfonate (AHQDS). A co-culture of Geobacter metallireducens and G. sulfurreducens metabolized ethanol with the reduction of fumarate much faster in the presence of AQDS, and there was an increase in cell protein. G. sulfurreducens was more abundant, consistent with G. sulfurreducens obtaining electrons from acetate that G. metallireducens produced from ethanol, as well as from AHQDS. Co-cultures initiated with a citrate synthase-deficient strain of G. sulfurreducens that was unable to use acetate as an electron donor also metabolized ethanol with the reduction of fumarate and cell growth, but acetate accumulated over time. G. sulfurreducens and G. metallireducens were equally abundant in these co-cultures reflecting the inability of the citrate synthase-deficient strain of G. sulfurreducens to metabolize acetate. Evaluation of the mechanisms by which G. sulfurreducens accepts electrons from AHQDS demonstrated that a strain deficient in outer-surface c-type cytochromes that are required for AQDS reduction was as effective at QUIET as the wild-type strain. Deletion of additional genes previously implicated in extracellular electron transfer also had no impact on QUIET. These results demonstrate that QUIET can yield sufficient energy to support the growth of both syntrophic partners, but that the mechanisms by which electrons are derived from extracellular hydroquinones require further investigation. PMID

  15. Incompatibility between Nuclear and Mitochondrial Genomes Contributes to an Interspecies Reproductive Barrier.

    PubMed

    Ma, Hong; Marti Gutierrez, Nuria; Morey, Robert; Van Dyken, Crystal; Kang, Eunju; Hayama, Tomonari; Lee, Yeonmi; Li, Ying; Tippner-Hedges, Rebecca; Wolf, Don P; Laurent, Louise C; Mitalipov, Shoukhrat

    2016-08-01

    Vertebrate cells carry two different genomes, nuclear (nDNA) and mitochondrial (mtDNA), both encoding proteins involved in oxidative phosphorylation. Because of the extensive interactions, adaptive coevolution of the two genomes must occur to ensure normal mitochondrial function. To investigate whether incompatibilities between these two genomes could contribute to interspecies reproductive barriers, we performed reciprocal mtDNA replacement (MR) in zygotes between widely divergent Mus m. domesticus (B6) and conplastic Mus m. musculus (PWD) mice. Transfer of MR1 cybrid embryos (B6nDNA-PWDmtDNA) supported normal development of F1 offspring with reduced male fertility but unaffected reproductive fitness in females. Furthermore, donor PWD mtDNA was faithfully transmitted through the germline into F2 and F3 generations. In contrast, reciprocal MR2 (PWDnDNA-B6mtDNA) produced high embryonic loss and stillborn rates, suggesting an association between mitochondrial function and infertility. These results strongly suggest that functional incompatibility between nuclear and mitochondrial genomes contributes to interspecies reproductive isolation in mammals. PMID:27425585

  16. Natural interspecies transfer of mitochondrial DNA in amphibians.

    PubMed Central

    Spolsky, C; Uzzell, T

    1984-01-01

    mtDNAs of two Central European water frog species, Rana ridibunda and Rana lessonae, were examined by electrophoresis of restriction enzyme fragments. Two types of mtDNA occur in R. ridibunda. One shares with mtDNA of R. lessonae 25.8% of 132 fragments generated by 19 enzymes, corresponding to a nucleotide sequence divergence of 8.1%; the other has diverged from R. lessonae mtDNA by only 0.3%. This latter type is a variant R. lessonae mtDNA that has been transferred into R. ridibunda; the introgression may have occurred via the hybridogenetic hybrid lineages collectively known as Rana esculenta. Of 37 R. ridibunda from Poland, 59% had the typical R. ridibunda mtDNA; 41% had the modified R. lessonae mtDNA as did a single individual from Switzerland (introduced). A single R. ridibunda from Turkey, outside the present range of R. lessonae, had the typical R. ridibunda mtDNA phenotype. Discordancies between inheritance of mitochondrial and nuclear genomes point up the danger of relying on a single molecular feature in reconstructing phylogeny. In addition, studies of mtDNA provide otherwise inaccessible information on complex evolutionary histories of closely related species. A knowledge of these complexities is important to an understanding of phylogenetic relationships and of the genetic processes that underlie the evolution of clonal taxa. Images PMID:6091109

  17. Collisionless inter-species energy transfer and turbulent heating in drift wave turbulence

    SciTech Connect

    Zhao, L.; Diamond, P. H.

    2012-08-15

    We reconsider the classic problems of calculating 'turbulent heating' and collisionless inter-species transfer of energy in drift wave turbulence. These issues are of interest for low collisionality, electron heated plasmas, such as ITER, where collisionless energy transfer from electrons to ions is likely to be significant. From the wave Poynting theorem at steady state, a volume integral over an annulus r{sub 1}=-S{sub r}|{sub r{sub 1}{sup r{sub 2}}}{ne}0. Here S{sub r} is the wave energy density flux in the radial direction. Thus, a wave energy flux differential across an annular region indeed gives rise to a net heating, in contrast to previous predictions. This heating is related to the Reynolds work by the zonal flow, since S{sub r} is directly linked to the zonal flow drive. In addition to net heating, there is inter-species heat transfer. For collisionless electron drift waves, the total turbulent energy source for collisionless heat transfer is due to quasilinear electron cooling. Subsequent quasilinear ion heating occurs through linear ion Landau damping. In addition, perpendicular heating via ion polarization currents contributes to ion heating. Since at steady state, Reynolds work of the turbulence on the zonal flow must balance zonal flow frictional damping ({approx}{nu}{sub ii}{sup 2}{approx}|(e{phi}(tilde sign)/T)|{sup 4}), it is no surprise that zonal flow friction appears as an important channel for ion heating. This process of energy transfer via zonal flow has not previously been accounted for in analyses of energy transfer. As an application, we compare the rate of turbulent energy transfer in a low collisionality plasma with the rate of the energy transfer by collisions. The result shows that the collisionless turbulent energy transfer is a significant energy coupling process for ITER plasma.

  18. Interspecies distances between propionic acid degraders and methanogens in syntrophic consortia for optimal hydrogen transfer.

    PubMed

    Felchner-Zwirello, Monika; Winter, Josef; Gallert, Claudia

    2013-10-01

    A mixed culture from an anaerobic biowaste digester was enriched on propionate and used to investigate interspecies hydrogen transfer in dependence of spatial distances between propionate degraders and methanogens. From 20.3 mM propionate, 20.8 mM acetate and 15.5 mM methane were formed. Maximum specific propionate oxidation and methane formation rates were 49 and 23 mmol mg(-1) day(-1), respectively. Propionate oxidation was inhibited by only 20 mM acetate by about 50 %. Intermediate formate formation during inhibited methanogensis was observed. The spatial distribution and the biovolume fraction of propionate degraders and of methanogens in relation to the total population during aggregate formation were determined. Measurements of interbacterial distances were conducted with fluorescence in situ hybridization by application of group-specific 16S rRNA-targeted probes and 3D image analyses. With increasing incubation time, floc formation and growth up to 54 μm were observed. Propionate degraders and methanogens were distributed randomly in the flocs. The methanogenic biovolume fraction was high at the beginning and remained constant over 42 days, whereas the fraction of propionate degraders increased with time during propionate feeding. Interbacterial distances between propionate degraders and methanogens decreased with time from 5.30 to 0.29 μm, causing an increase of the maximum possible hydrogen flux from 1.1 to 10.3 nmol ml(-1) min(-1). The maximum possible hydrogen flux was always higher than the hydrogen formation and consumption rate, indicating that reducing the interspecies distance by aggregation is advantageous in complex ecosystems. PMID:23233207

  19. Direct interspecies electron transfer accelerates syntrophic oxidation of butyrate in paddy soil enrichments.

    PubMed

    Li, Huijuan; Chang, Jiali; Liu, Pengfei; Fu, Li; Ding, Dewen; Lu, Yahai

    2015-05-01

    Syntrophic interaction occurs during anaerobic fermentation of organic substances forming methane as the final product. H2 and formate are known to serve as the electron carriers in this process. Recently, it has been shown that direct interspecies electron transfer (DIET) occurs for syntrophic CH4 production from ethanol and acetate. Here, we constructed paddy soil enrichments to determine the involvement of DIET in syntrophic butyrate oxidation and CH4 production. The results showed that CH4 production was significantly accelerated in the presence of nanoFe3 O4 in all continuous transfers. This acceleration increased with the increase of nanoFe3 O4 concentration but was dismissed when Fe3 O4 was coated with silica that insulated the mineral from electrical conduction. NanoFe3 O4 particles were found closely attached to the cell surfaces of different morphology, thus bridging cell connections. Molecular approaches, including DNA-based stable isotope probing, revealed that the bacterial Syntrophomonadaceae and Geobacteraceae, and the archaeal Methanosarcinaceae, Methanocellales and Methanobacteriales, were involved in the syntrophic butyrate oxidation and CH4 production. Among them, the growth of Geobacteraceae strictly relied on the presence of nanoFe3 O4 and its electrical conductivity in particular. Other organisms, except Methanobacteriales, were present in enrichments regardless of nanoFe3 O4 amendment. Collectively, our study demonstrated that the nanoFe3 O4 -facilitated DIET occurred in syntrophic CH4 production from butyrate, and Geobacter species played the key role in this process in the paddy soil enrichments. PMID:25059331

  20. Unexpected Specificity of Interspecies Cobamide Transfer from Geobacter spp. to Organohalide-Respiring Dehalococcoides mccartyi Strains

    PubMed Central

    Yan, Jun; Ritalahti, Kirsti M.; Wagner, Darlene D.

    2012-01-01

    Dehalococcoides mccartyi strains conserve energy from reductive dechlorination reactions catalyzed by corrinoid-dependent reductive dehalogenase enzyme systems. Dehalococcoides lacks the ability for de novo corrinoid synthesis, and pure cultures require the addition of cyanocobalamin (vitamin B12) for growth. In contrast, Geobacter lovleyi, which dechlorinates tetrachloroethene to cis-1,2-dichloroethene (cis-DCE), and the nondechlorinating species Geobacter sulfurreducens have complete sets of cobamide biosynthesis genes and produced 12.9 ± 2.4 and 24.2 ± 5.8 ng of extracellular cobamide per liter of culture suspension, respectively, during growth with acetate and fumarate in a completely synthetic medium. G. lovleyi-D. mccartyi strain BAV1 or strain FL2 cocultures provided evidence for interspecies corrinoid transfer, and cis-DCE was dechlorinated to vinyl chloride and ethene concomitant with Dehalococcoides growth. In contrast, negligible increase in Dehalococcoides 16S rRNA gene copies and insignificant dechlorination occurred in G. sulfurreducens-D. mccartyi strain BAV1 or strain FL2 cocultures. Apparently, G. lovleyi produces a cobamide that complements Dehalococcoides' nutritional requirements, whereas G. sulfurreducens does not. Interestingly, Dehalococcoides dechlorination activity and growth could be restored in G. sulfurreducens-Dehalococcoides cocultures by adding 10 μM 5′,6′-dimethylbenzimidazole. Observations made with the G. sulfurreducens-Dehalococcoides cocultures suggest that the exchange of the lower ligand generated a cobalamin, which supported Dehalococcoides activity. These findings have implications for in situ bioremediation and suggest that the corrinoid metabolism of Dehalococcoides must be understood to faithfully predict, and possibly enhance, reductive dechlorination activities. PMID:22773645

  1. Potential for direct interspecies electron transfer in an electric-anaerobic system to increase methane production from sludge digestion

    PubMed Central

    Zhao, Zhiqiang; Zhang, Yaobin; Wang, Liying; Quan, Xie

    2015-01-01

    Direct interspecies electron transfer (DIET) between Geobacter species and Methanosaeta species is an alternative to interspecies hydrogen transfer (IHT) in anaerobic digester, which however has not been established in anaerobic sludge digestion as well as in bioelectrochemical systems yet. In this study, it was found that over 50% of methane production of an electric-anaerobic sludge digester was resulted from unknown pathway. Pyrosequencing analysis revealed that Geobacter species were significantly enriched with electrodes. Fluorescence in situ hybridization (FISH) further confirmed that the dominant Geobacter species enriched belonged to Geobacter metallireducens. Together with Methanosaeta species prevailing in the microbial communities, the direct electron exchange between Geobacter species and Methanosaeta species might be an important reason for the “unknown” increase of methane production. Conductivity of the sludge in this electric-anaerobic digester was about 30% higher than that of the sludge in a control digester without electrodes. This study not only revealed for the first time that DIET might be the important mechanism on the methanogenesis of bioelectrochemical system, but also provided a new method to enhance DIET by means of bioelectric enrichment of Geobacter species. PMID:26057581

  2. Expanding the Diet for DIET: Electron Donors Supporting Direct Interspecies Electron Transfer (DIET) in Defined Co-Cultures

    PubMed Central

    Wang, Li-Ying; Nevin, Kelly P.; Woodard, Trevor L.; Mu, Bo-Zhong; Lovley, Derek R.

    2016-01-01

    Direct interspecies electron transfer (DIET) has been recognized as an alternative to interspecies H2 transfer as a mechanism for syntrophic growth, but previous studies on DIET with defined co-cultures have only documented DIET with ethanol as the electron donor in the absence of conductive materials. Co-cultures of Geobacter metallireducens and Geobacter sulfurreducens metabolized propanol, butanol, propionate, and butyrate with the reduction of fumarate to succinate. G. metallireducens utilized each of these substrates whereas only electrons available from DIET supported G. sulfurreducens respiration. A co-culture of G. metallireducens and a strain of G. sulfurreducens that could not metabolize acetate oxidized acetate with fumarate as the electron acceptor, demonstrating that acetate can also be syntrophically metabolized via DIET. A co-culture of G. metallireducens and Methanosaeta harundinacea previously shown to syntrophically convert ethanol to methane via DIET metabolized propanol or butanol as the sole electron donor, but not propionate or butyrate. The stoichiometric accumulation of propionate or butyrate in the propanol- or butanol-fed cultures demonstrated that M. harundinaceae could conserve energy to support growth solely from electrons derived from DIET. Co-cultures of G. metallireducens and Methanosarcina barkeri could also incompletely metabolize propanol and butanol and did not metabolize propionate or butyrate as sole electron donors. These results expand the range of substrates that are known to be syntrophically metabolized through DIET, but suggest that claims of propionate and butyrate metabolism via DIET in mixed microbial communities warrant further validation. PMID:26973614

  3. Communities stimulated with ethanol to perform direct interspecies electron transfer for syntrophic metabolism of propionate and butyrate.

    PubMed

    Zhao, Zhiqiang; Zhang, Yaobin; Yu, Qilin; Dang, Yan; Li, Yang; Quan, Xie

    2016-10-01

    Direct interspecies electron transfer (DIET) has been considered as an alternative to interspecies H2 transfer (IHT) for syntrophic metabolism, but the microorganisms capable of metabolizing the key intermediates, such as propionate and butyrate, via DIET have yet to be described. A strategy of culturing the enrichments with ethanol as a DIET substrate to stimulate the communities for the syntrophic metabolism of propionate and/or butyrate was proposed in this study. The results showed that the syntrophic propionate and/or butyrate degradation was significantly improved in the ethanol-stimulated reactor when propionate/butyrate was the sole carbon source. The conductivity of the ethanol-stimulated enrichments was as 5 folds (for propionate)/76 folds (for butyrate) as that of the traditional enrichments (never ethanol fed). Microbial community analysis revealed that Geobacter species known to proceed DIET were only detected in the ethanol-stimulated enrichments. Together with the significant increase of Methanosaeta and Methanosarcina species in these enrichments, the potential DIET between Geobacter and Methanosaeta or Methanosarcina species might be established to improve the syntrophic propionate and/or butyrate degradation. Further experiments demonstrated that granular activated carbon (GAC) could improve the syntrophic metabolism of propionate and/or butyrate of the ethanol-stimulated enrichments, while almost no effects on the traditional enrichments. Also, the high H2 partial pressure could inhibit the syntrophic propionate and/or butyrate degradation of the traditional enrichments, but its effect on that of the ethanol-stimulated enrichments was negligible. PMID:27403870

  4. N. elongata produces type IV pili that mediate interspecies gene transfer with N. gonorrhoeae.

    PubMed

    Higashi, Dustin L; Biais, Nicolas; Weyand, Nathan J; Agellon, Al; Sisko, Jennifer L; Brown, Lewis M; So, Magdalene

    2011-01-01

    The genus Neisseria contains at least eight commensal and two pathogenic species. According to the Neisseria phylogenetic tree, commensals are basal to the pathogens. N. elongata, which is at the opposite end of the tree from N. gonorrhoeae, has been observed to be fimbriated, and these fimbriae are correlated with genetic competence in this organism. We tested the hypothesis that the fimbriae of N. elongata are Type IV pili (Tfp), and that Tfp functions in genetic competence. We provide evidence that the N. elongata fimbriae are indeed Tfp. Tfp, as well as the DNA Uptake Sequence (DUS), greatly enhance N. elongata DNA transformation. Tfp allows N. elongata to make intimate contact with N. gonorrhoeae and to mediate the transfer of antibiotic resistance markers between these two species. We conclude that Tfp functional for genetic competence is a trait of a commensal member of the Neisseria genus. Our findings provide a mechanism for the horizontal gene transfer that has been observed among Neisseria species. PMID:21731720

  5. Development of a pheasant interspecies primordial germ cell transfer to chicken embryo: effect of donor cell sex on chimeric semen production.

    PubMed

    Kang, S J; Choi, J W; Park, K J; Lee, Y M; Kim, T M; Sohn, S H; Lim, J M; Han, J Y

    2009-09-01

    This study was conducted to evaluate whether the sex of donor primordial germ cells (PGCs) influences production of chimeric semen from recipient hatchlings produced by interspecies transfer between pheasant (Phasianus colchicus) and chicken (Gallus gallus). Pheasant PGCs were retrieved from 7-d-old embryos and subsequently transferred into circulatory blood of 2.5-d-old (Stage 17) embryos. The sex of embryos was discerned 3 to 6 days after laying, and in preliminary study, overall rate of embryo survival after sexing was 74.6% with male-to-female ratio of 0.49 to 0.51. In Experiment 1, magnetic-activated cell sorting (MACS) using QCR1 antibody was effective for enriching the population of male and female PGCs in gonadal cells (9.2- to 12.5-fold and 10.8- to 19.5-fold increase, respectively). In Experiment 2, an increase in the number of hatchlings producing chimeric semen was detected after the homosexual transfer of male-to-male compared with that after the heterosexual transfer of female-to-male (68% to 88%). Significant increase was found in the frequency of chimeric semen production (0.96 to 1.68 times); production of pheasant progenies by artificial insemination using chimeric semen was also increased in the homosexual transfer (0 to 3 cases). In conclusion, the homosexual PGC transfer of male-to-male yielded better rate of generating pheasant progenies after test cross-reproduction than that of the heterosexual transfer of female-to-male, which could improve the efficiency of interspecies germ cell transfer system. PMID:19515408

  6. Nuclear propulsion for orbital transfer

    SciTech Connect

    Beale, G.A.; Lawrence, T.J. )

    1989-06-01

    The state of the art in nuclear propulsion for orbital transfer is discussed. Cryogenic propulsion, electric propulsion, solar-thermal propulsion and direct nuclear propulsion are examined in this context. New technologies with exceptional promise are addressed, emphasizing the particle test bed nuclear engine.

  7. Transfer reactions in nuclear astrophysics

    NASA Astrophysics Data System (ADS)

    Bardayan, D. W.

    2016-08-01

    To a high degree many aspects of the large-scale behavior of objects in the Universe are governed by the underlying nuclear physics. In fact the shell structure of nuclear physics is directly imprinted into the chemical abundances of the elements. The tranquility of the night sky is a direct result of the relatively slow rate of nuclear reactions that control and determines a star’s fate. Understanding the nuclear structure and reaction rates between nuclei is vital to understanding our Universe. Nuclear-transfer reactions make accessible a wealth of knowledge from which we can extract much of the required nuclear physics information. A review of transfer reactions for nuclear astrophysics is presented with an emphasis on the experimental challenges and opportunities for future development.

  8. Potential enhancement of direct interspecies electron transfer for syntrophic metabolism of propionate and butyrate with biochar in up-flow anaerobic sludge blanket reactors.

    PubMed

    Zhao, Zhiqiang; Zhang, Yaobin; Holmes, Dawn E; Dang, Yan; Woodard, Trevor L; Nevin, Kelly P; Lovley, Derek R

    2016-06-01

    Promoting direct interspecies electron transfer (DIET) to enhance syntrophic metabolism may be a strategy for accelerating the conversion of organic wastes to methane, but microorganisms capable of metabolizing propionate and butyrate via DIET under methanogenic conditions have yet to be identified. In an attempt to establish methanogenic communities metabolizing propionate or butyrate with DIET, enrichments were initiated with up-flow anaerobic sludge blanket (UASB), similar to those that were previously reported to support communities that metabolized ethanol with DIET that relied on direct biological electrical connections. In the absence of any amendments, microbial communities enriched were dominated by microorganisms closely related to pure cultures that are known to metabolize propionate or butyrate to acetate with production of H2. When biochar was added to the reactors there was a substantial enrichment on the biochar surface of 16S rRNA gene sequences closely related to Geobacter and Methanosaeta species known to participate in DIET. PMID:26967338

  9. Nuclear technology transfer to China

    SciTech Connect

    Crane, A.T.

    1987-01-01

    China has severe power shortages and considerable nuclear expertise available from its military programs. These factors led to great expectations of how fast its nuclear power program might expand. The U.S. recently implemented a controversial nuclear cooperation agreement with China, permitting U.S. companies to compete if this market reopens. The major concern over the agreement was that in the past China apparently showed an alarming disregard for the dangers of nuclear proliferation. It is unlikely that China would use nuclear power equipment to further its nuclear weapons program, but the effectiveness of the U.S. nonproliferation stance has been in part dependent on other countries viewing our position as uncompromising. The vagueness of certain provisions in the agreement with China may have weakened this stance. Another concern is that access to U.S. pressurized water reactor technology could improve their submarine reactors, which could be detrimental to U.S. security interests if relations with China deteriorate. However, it appears that the only significant advantage that would accrue would be a general upgrading of management practices and quality control, which would be available from any other nuclear supplier. If the opportunity for the sale of nuclear equipment to China emerges, the nuclear technology transfer that would be involved, if carefully managed, should contribute to the national interest.

  10. Bovine somatic cell nuclear transfer.

    PubMed

    Ross, Pablo J; Cibelli, Jose B

    2010-01-01

    Somatic cell nuclear transfer (SCNT) is a technique by which the nucleus of a differentiated cell is introduced into an oocyte from which its genetic material has been removed by a process called enucleation. In mammals, the reconstructed embryo is artificially induced to initiate embryonic development (activation). The oocyte turns the somatic cell nucleus into an embryonic nucleus. This process is called nuclear reprogramming and involves an important change of cell fate, by which the somatic cell nucleus becomes capable of generating all the cell types required for the formation of a new individual, including extraembryonic tissues. Therefore, after transfer of a cloned embryo to a surrogate mother, an offspring genetically identical to the animal from which the somatic cells where isolated, is born. Cloning by nuclear transfer has potential applications in agriculture and biomedicine, but is limited by low efficiency. Cattle were the second mammalian species to be cloned after Dolly the sheep, and it is probably the most widely used species for SCNT experiments. This is, in part due to the high availability of bovine oocytes and the relatively higher efficiency levels usually obtained in cattle. Given the wide utilization of this species for cloning, several alternatives to this basic protocol can be found in the literature. Here we describe a basic protocol for bovine SCNT currently being used in our laboratory, which is amenable for the use of the nuclear transplantation technique for research or commercial purposes. PMID:20336522

  11. Cytoplasmic Determination of Meiotic Spindle Size Revealed by a Unique Inter-Species Germinal Vesicle Transfer Model

    PubMed Central

    Wang, Zhong-Wei; Zhang, Guang-Li; Schatten, Heide; Carroll, John; Sun, Qing-Yuan

    2016-01-01

    Spindle sizes are different in diverse species and cell types. In frogs, the meiotic spindle size is positively correlated with the egg cell volume. Across species, relatively small mouse oocytes (70–80 μm) have a relatively large spindle while larger pig oocytes (about 120 μm) have a considerably smaller spindle. In this study we investigated whether species-specific oocyte spindle size was determined by cytoplasmic or nuclear factors. By exchanging the germinal vesicle between mouse and pig oocytes, we obtained two kinds of reconstructed oocytes: one with mouse ooplasm and pig GV (mCy-pGV oocyte), and the other with pig ooplasm and mouse GV (pCy-mGV oocyte). We show that the MII spindle size of the mCy-pGV oocyte is similar to that of the mouse meiotic spindle and significantly larger than that of the pig meiotic spindle. The timing of oocyte maturation also followed that of the species from which the oocyte cytoplasm arose, although some impact of the origin of the GV was observed. These data suggest that spindle size and the timing of meiotic progression are governed by cytoplasmic components rather than cytoplasmic volume and GV materials. PMID:26813698

  12. Somatic cell nuclear transfer in zebrafish.

    PubMed

    Siripattarapravat, Kannika; Pinmee, Boonya; Venta, Patrick J; Chang, Chia-Cheng; Cibelli, Jose B

    2009-10-01

    We developed a method for somatic cell nuclear transfer in zebrafish using laser-ablated metaphase II eggs as recipients, the micropyle for transfer of the nucleus and an egg activation protocol after nuclear reconstruction. We produced clones from cells of both embryonic and adult origins, although the latter did not give rise to live adult clones. PMID:19718031

  13. Reproduction of wild birds via interspecies germ cell transplantation.

    PubMed

    Kang, Seok Jin; Choi, Jin Won; Kim, Sun Young; Park, Kyung Je; Kim, Tae Min; Lee, Young Mok; Kim, Heebal; Lim, Jeong Mook; Han, Jae Yong

    2008-11-01

    The present study was conducted to apply an interspecies germ cell transfer technique to wild bird reproduction. Pheasant (Phasianus colchicus) primordial germ cells (PGCs) retrieved from the gonads of 7-day-old embryos were transferred to the bloodstream of 2.5-day-old chicken (Gallus gallus) embryos. Pheasant-to-chicken germline chimeras hatched from the recipient embryos, and 10 pheasants were derived from testcross reproduction of the male chimeras with female pheasants. Gonadal migration of the transferred PGCs, their involvement in spermatogenesis, and production of chimeric semen were confirmed. The phenotype of pheasant progenies derived from the interspecies transfer was identical to that of wild pheasants. The average efficiency of reproduction estimated from the percentage of pheasants to total progenies was 17.5%. In conclusion, interspecies germ cell transfer into a developing embryo can be used for wild bird reproduction, and this reproductive technology may be applicable in conserving endangered bird species. PMID:18685127

  14. Dry Transfer Systems for Used Nuclear Fuel

    SciTech Connect

    Brett W. Carlsen; Michaele BradyRaap

    2012-05-01

    The potential need for a dry transfer system (DTS) to enable retrieval of used nuclear fuel (UNF) for inspection or repackaging will increase as the duration and quantity of fuel in dry storage increases. This report explores the uses for a DTS, identifies associated general functional requirements, and reviews existing and proposed systems that currently perform dry fuel transfers. The focus of this paper is on the need for a DTS to enable transfer of bare fuel assemblies. Dry transfer systems for UNF canisters are currently available and in use for transferring loaded canisters between the drying station and storage and transportation casks.

  15. Heat transfer in a nuclear rocket engine

    SciTech Connect

    Konyukhov, G.V.; Petrov, A.I.

    1995-02-01

    Special features of heat transfer in the reactor of a nuclear rocket engine (NRE) are dealt with. It is shown that the design of the cooling system of the NRE reactor is governed by its stability to small deviations of the parameters from the corresponding calculated values and the possibility of compensating for effects due to nonuniformities and distrubances of various types and scales.

  16. 10 CFR 70.42 - Transfer of special nuclear material.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 2 2011-01-01 2011-01-01 false Transfer of special nuclear material. 70.42 Section 70.42 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) DOMESTIC LICENSING OF SPECIAL NUCLEAR MATERIAL Acquisition, Use and Transfer of Special Nuclear Material, Creditors' Rights § 70.42 Transfer of...

  17. 10 CFR 70.42 - Transfer of special nuclear material.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 2 2010-01-01 2010-01-01 false Transfer of special nuclear material. 70.42 Section 70.42 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) DOMESTIC LICENSING OF SPECIAL NUCLEAR MATERIAL Acquisition, Use and Transfer of Special Nuclear Material, Creditors' Rights § 70.42 Transfer of...

  18. Nuclear transfer and transgenesis in the pig.

    PubMed

    Kurome, Mayuko; Kessler, Barbara; Wuensch, Annegret; Nagashima, Hiroshi; Wolf, Eckhard

    2015-01-01

    Somatic cell nuclear transfer (SCNT) using genetically modified donor cells facilitates the generation of tailored pig models for biomedical research and for xenotransplantation. Up to now, SCNT is the main way to generate gene-targeted pigs, since germ line-competent pluripotent stem cells are not available for this species. In this chapter, we introduce our routine workflow for the production of genetically engineered pigs, especially focused on the genetic modification of somatic donor cells, SCNT using in vitro matured oocytes, and laparoscopic embryo transfer. PMID:25287337

  19. Bovine ooplasm partially remodels primate somatic nuclei following somatic cell nuclear transfer.

    PubMed

    Wang, Kai; Beyhan, Zeki; Rodriguez, Ramon M; Ross, Pablo J; Iager, Amy E; Kaiser, German G; Chen, Ying; Cibelli, Jose B

    2009-03-01

    Interspecies somatic cell nuclear transfer (iSCNT) has the potential to become a useful tool to address basic questions about the nucleus-cytoplasm interactions between species. It has also been proposed as an alternative for the preservation of endangered species and to derive autologous embryonic stem cells. Using chimpanzee/ bovine iSCNT as our experimental model we studied the early epigenetic events that take place soon after cell fusion until embryonic genome activation (EGA). Our analysis suggested partial EGA in iSCNT embryos at the eight-cell stage, as indicated by Br-UTP incorporation and expression of chimpanzee embryonic genes. Oct4, Stella, Crabp1, CCNE2, CXCL6, PTGER4, H2AFZ, c-MYC, KLF4, and GAPDH transcripts were expressed, while Nanog, Glut1, DSC2, USF2, Adrbk1, and Lin28 failed to be activated. Although development of iSCNT embryos did not progress beyond the 8- to 16-cell stage, chromatin remodeling events, monitored by H3K27 methylation, H4K5 acetylation, and global DNA methylation, were similar in both intra- and interspecies SCNT embryos. However, bisulfite sequencing indicated incomplete demethylation of Oct4 and Nanog promoters in eight-cell iSCNT embryos. ATP production levels were significantly higher in bovine SCNT embryos than in iSCNT embryos, TUNEL assays did not reveal any difference in the apoptotic status of the nuclei from both types of embryos. Collectively, our results suggest that bovine ooplasm can partially remodel chimpanzee somatic nuclei, and provides insight into some of the current barriers iSCNT must overcome if further embryonic development is to be expected. PMID:19196039

  20. 48 CFR 970.4402-4 - Nuclear material transfers.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 5 2011-10-01 2011-10-01 false Nuclear material transfers... 970.4402-4 Nuclear material transfers. (a) Management and operating contractors, in preparing... nuclear material, shall be required to assure that each such subcontract or agreement contains a—...

  1. 48 CFR 970.4402-4 - Nuclear material transfers.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Nuclear material transfers... 970.4402-4 Nuclear material transfers. (a) Management and operating contractors, in preparing... nuclear material, shall be required to assure that each such subcontract or agreement contains a—...

  2. Interspecies Dissemination of a Mobilizable Plasmid Harboring blaIMP-19 and the Possibility of Horizontal Gene Transfer in a Single Patient.

    PubMed

    Yamamoto, Masaki; Matsumura, Yasufumi; Gomi, Ryota; Matsuda, Tomonari; Tanaka, Michio; Nagao, Miki; Takakura, Shunji; Uemoto, Shinji; Ichiyama, Satoshi

    2016-09-01

    Carbapenemase-producing Gram-negative bacilli have been a global concern over the past 2 decades because these organisms can cause severe infections with high mortality rates. Carbapenemase genes are often carried by mobile genetic elements, and resistance plasmids can be transferred through conjugation. We conducted whole-genome sequencing (WGS) to demonstrate that the same plasmid harboring a metallo-β-lactamase gene was detected in two different species isolated from a single patient. Metallo-β-lactamase-producing Achromobacter xylosoxidans (KUN4507), non-metallo-β-lactamase-producing Klebsiella pneumoniae (KUN4843), and metallo-β-lactamase-producing K. pneumoniae (KUN5033) were sequentially isolated from a single patient and then analyzed in this study. Antimicrobial susceptibility testing, molecular typing (pulsed-field gel electrophoresis and multilocus sequence typing), and conjugation analyses were performed by conventional methods. Phylogenetic and molecular clock analysis of K. pneumoniae isolates were performed with WGS, and the nucleotide sequences of plasmids detected from these isolates were determined using WGS. Conventional molecular typing revealed that KUN4843 and KUN5033 were identical, whereas the phylogenetic tree analysis revealed a slight difference. These two isolates were separated from the most recent common ancestor 0.74 years before they were isolated. The same resistance plasmid harboring blaIMP-19 was detected in metallo-β-lactamase-producing A. xylosoxidans and K. pneumoniae Although this plasmid was not self-transferable, the conjugation of this plasmid from A. xylosoxidans to non-metallo-β-lactamase-producing K. pneumoniae was successfully performed. The susceptibility patterns for metallo-β-lactamase-producing K. pneumoniae and the transconjugant were similar. These findings supported the possibility of the horizontal transfer of plasmid-borne blaIMP-19 from A. xylosoxidans to K. pneumoniae in a single patient. PMID:27381397

  3. Passive heat transfer means for nuclear reactors

    DOEpatents

    Burelbach, James P.

    1984-01-01

    An improved passive cooling arrangement is disclosed for maintaining adjacent or related components of a nuclear reactor within specified temperature differences. Specifically, heat pipes are operatively interposed between the components, with the vaporizing section of the heat pipe proximate the hot component operable to cool it and the primary condensing section of the heat pipe proximate the other and cooler component operable to heat it. Each heat pipe further has a secondary condensing section that is located outwardly beyond the reactor confinement and in a secondary heat sink, such as air ambient the containment, that is cooler than the other reactor component. Means such as shrouding normally isolated the secondary condensing section from effective heat transfer with the heat sink, but a sensor responds to overheat conditions of the reactor to open the shrouding, which thereby increases the cooling capacity of the heat pipe. By having many such heat pipes, an emergency passive cooling system is defined that is operative without electrical power.

  4. Somatic Cell Nuclear Transfer in the Mouse

    NASA Astrophysics Data System (ADS)

    Kishigami, Satoshi; Wakayama, Teruhiko

    Somatic cell nuclear transfer (SCNT) has become a unique and powerful tool for epigenetic reprogramming research and gene manipulation in animals since “Dolly,” the first animal cloned from an adult cell was reported in 1997. Although the success rates of somatic cloning have been inefficient and the mechanism of reprogramming is still largely unknown, this technique has been proven to work in more than 10 mammalian species. Among them, the mouse provides the best model for both basic and applied research of somatic cloning because of its abounding genetic resources, rapid sexual maturity and propagation, minimal requirements for housing, etc. This chapter describes a basic protocol for mouse cloning using cumulus cells, the most popular cell type for NT, in which donor nuclei are directly injected into the oocyte using a piezo-actuated micromanipulator. In particular, we focus on a new, more efficient mouse cloning protocol using trichostatin A (TSA), a histone deacetylase (HDAC) inhibitor, which increases both in vitro and in vivo developmental rates from twofold to fivefold. This new method including TSA will be helpful to establish mouse cloning in many laboratories.

  5. Somatic cell nuclear transfer in the mouse.

    PubMed

    Kishigami, Satoshi; Wakayama, Teruhiko

    2009-01-01

    Somatic cell nuclear transfer (SCNT) has become a unique and powerful tool for epigenetic reprogramming research and gene manipulation in animals since "Dolly," the first animal cloned from an adult cell was reported in 1997. Although the success rates of somatic cloning have been inefficient and the mechanism of reprogramming is still largely unknown, this technique has been proven to work in more than 10 mammalian species. Among them, the mouse provides the best model for both basic and applied research of somatic cloning because of its abounding genetic resources, rapid sexual maturity and propagation, minimal requirements for housing, etc. This chapter describes a basic protocol for mouse cloning using cumulus cells, the most popular cell type for NT, in which donor nuclei are directly injected into the oocyte using a piezo-actuated micromanipulator. In particular, we focus on a new, more efficient mouse cloning protocol using trichostatin A (TSA), a histone deacetylase (HDAC) inhibitor, which increases both in vitro and in vivo developmental rates from twofold to fivefold. This new method including TSA will be helpful to establish mouse cloning in many laboratories. PMID:19085136

  6. 10 CFR 70.42 - Transfer of special nuclear material.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 2 2012-01-01 2012-01-01 false Transfer of special nuclear material. 70.42 Section 70.42 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) DOMESTIC LICENSING OF SPECIAL NUCLEAR MATERIAL... agreement with the Commission or the Atomic Energy Commission under section 274 of the Act, if the...

  7. 10 CFR 70.42 - Transfer of special nuclear material.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 2 2013-01-01 2013-01-01 false Transfer of special nuclear material. 70.42 Section 70.42 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) DOMESTIC LICENSING OF SPECIAL NUCLEAR MATERIAL... agreement with the Commission or the Atomic Energy Commission under section 274 of the Act, if the...

  8. 10 CFR 70.42 - Transfer of special nuclear material.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 2 2014-01-01 2014-01-01 false Transfer of special nuclear material. 70.42 Section 70.42 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) DOMESTIC LICENSING OF SPECIAL NUCLEAR MATERIAL... agreement with the Commission or the Atomic Energy Commission under section 274 of the Act, if the...

  9. Interspecies dosimetry of reactive gases

    SciTech Connect

    Miller, F.J.; Overton, J.H.; Gerrity, T.R.; Graham, R.C.

    1987-03-01

    The development of dosimetry models that can provide a description of the uptake and distribution of inhaled compounds throughout the body and the availability of animal toxicological data are integral components for a full evaluation of potential risks associated with human exposure. Interspecies dosimetric comparisons must be approached using a model conceptualization that incorporates the major factors affecting the uptake of the gas, such as respiratory tract morphology, route of breathing, depth and rate of breathing, physicochemical properties of the gas, etc. Modeling efforts thus far have primarily focused on ozone. A comparison of theoretical predictions of delivered dose of ozone to the lower respiratory tract of man shows good agreement with dose estimates derived from experimental measurements. Applications to ozone toxicological data in animals and man have been examined that incorporate the use of dosimetry models in studying quantitative dose-response relationships.

  10. Electronic and Nuclear Factors in Charge and Excitation Transfer

    SciTech Connect

    Piotr Piotrowiak

    2004-09-28

    We report the and/or state of several subprojects of our DOE sponsored research on Electronic and Nuclear Factors in Electron and Excitation Transfer: (1) Construction of an ultrafast Ti:sapphire amplifier. (2) Mediation of electronic interactions in host-guest molecules. (3) Theoretical models of electrolytes in weakly polar media. (4) Symmetry effects in intramolecular excitation transfer.

  11. Orbital transfer of large space structures with nuclear electric rockets

    NASA Technical Reports Server (NTRS)

    Silva, T. H.; Byers, D. C.

    1980-01-01

    This paper discusses the potential application of electric propulsion for orbit transfer of a large spacecraft structure from low earth orbit to geosynchronous altitude in a deployed configuration. The electric power was provided by the spacecraft nuclear reactor space power system on a shared basis during transfer operations. Factors considered with respect to system effectiveness included nuclear power source sizing, electric propulsion thruster concept, spacecraft deployment constraints, and orbital operations and safety. It is shown that the favorable total impulse capability inherent in electric propulsion provides a potential economic advantage over chemical propulsion orbit transfer vehicles by reducing the number of Space Shuttle flights in ground-to-orbit transportation requirements.

  12. Handmade cloning: the future way of nuclear transfer?

    PubMed

    Vajta, Gábor

    2007-06-01

    The topic of this review is an alternative technique for somatic cell nuclear transfer. Removal of the zona pellucida facilitates manipulations of mammalian oocytes and early embryos, and problems related to their subsequent culture are commonly overestimated. This approach enables radical modifications to somatic cell nuclear transfer, and the handmade cloning (HMC) technique is now successfully applied to an increasing numbers of species. HMC radically decreases costs and the need for a skilled workforce; furthermore, it increases productivity, enables cryopreservation, and results in birth rates comparable, or even higher, than those achievable by micromanipulation-based traditional cloning (TC). The new technique can accelerate technology transfer and standardization and, eventually, might contribute to the widespread application of cloning. Additionally, HMC offers unique possibilities for the automation of somatic cell nuclear transfer. PMID:17434218

  13. INTERSPECIES MODELING OF INHALED PARTICLE DEPOSITION

    EPA Science Inventory

    To evaluate the potential toxic effects of ambient contaminants or therapeutic effects of airborne drugs, inhalation exposure experiments can be performed with surrogate laboratory animals. erein, an interspecies particle deposition theory is presented for physiologically based p...

  14. INTERSPECIES DOSIMETRY MODELS FOR PULMONARY PHARMACOLOGY

    EPA Science Inventory

    Interspecies Dosimetry Models for Pulmonary Pharmacology

    Ted B. Martonen, Jeffry D. Schroeter, and John S. Fleming

    Experimental Toxicology Division, National Health and Environmental Effects Research Laboratory, U.S. Environmental Protection Agency, Research Triangl...

  15. Nuclear interlevel transfer driven by electronic transitions

    SciTech Connect

    Solem, J.C.; Rinker, G.

    1985-01-01

    We show how a gamma-ray laser might be made by optically exciting a transfer of population from a long-lived isomer to an energetically adjacent short-lived state of the same nucleus. We compare the advantages of using transitions of high multipolarity versus transitions of low multi-polarity. Preliminary numerical investigations of the mechanism show it to be somewhat favorable. 35 refs., 4 figs.

  16. Disposal modes for Mars transfer nuclear propulsion

    NASA Technical Reports Server (NTRS)

    Stancati, Michael L.; Friedlander, Alan L.

    1991-01-01

    A managed disposal approach is proposed that would place the nuclear stage or vehicle in a highly stable orbit at modest cost to mission performance. The approach requires only a small increase in initial mass in LEO, but should be included in preliminary trajectory design and performance calculations. The mass penalty is expected to be larger for all-up flight profiles, or in cases of high-thrust propulsion systems for the cargo vehicle.

  17. 48 CFR 970.4402-4 - Nuclear material transfers.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 5 2012-10-01 2012-10-01 false Nuclear material transfers. 970.4402-4 Section 970.4402-4 Federal Acquisition Regulations System DEPARTMENT OF ENERGY AGENCY SUPPLEMENTARY REGULATIONS DOE MANAGEMENT AND OPERATING CONTRACTS Management and Operating Contractor...

  18. 48 CFR 970.4402-4 - Nuclear material transfers.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 5 2014-10-01 2014-10-01 false Nuclear material transfers. 970.4402-4 Section 970.4402-4 Federal Acquisition Regulations System DEPARTMENT OF ENERGY AGENCY SUPPLEMENTARY REGULATIONS DOE MANAGEMENT AND OPERATING CONTRACTS Management and Operating Contractor...

  19. 48 CFR 970.4402-4 - Nuclear material transfers.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 5 2013-10-01 2013-10-01 false Nuclear material transfers. 970.4402-4 Section 970.4402-4 Federal Acquisition Regulations System DEPARTMENT OF ENERGY AGENCY SUPPLEMENTARY REGULATIONS DOE MANAGEMENT AND OPERATING CONTRACTS Management and Operating Contractor...

  20. Human somatic cell nuclear transfer is alive and well.

    PubMed

    Cibelli, Jose B

    2014-06-01

    In this issue, Chung et al. (2014) generate human embryonic stem cells by fusing an adult somatic cell to a previously enucleated human oocyte, in agreement with recent reports by the Mitalipov and Egli groups. We can now safely say that human somatic cell nuclear transfer is alive and well. PMID:24905159

  1. Nuclear Waste Cross Site Transfer Pump Operational Resonance Resolution

    SciTech Connect

    HAUCK, F.M.

    1999-12-01

    Two single-volute, multi-stage centrifugal pumps are installed at a nuclear waste transfer station operated by the Department of Energy in Hanford, WA. The two parallel 100% pumps are Variable Frequency Drive operated and designed to transport waste etc.

  2. Theoretical studies on shaking processes in nuclear transfer reactions

    NASA Astrophysics Data System (ADS)

    Sharma, Prashant; Nandi, Tapan

    2015-09-01

    The probabilities of shaking processes during nuclear transfer reactions have been studied using the Mukoyama formalism after the re-examination of formalism for β-decay processes. Electron shakeoff probabilities have been calculated for the α-transfer reaction in the range of Z = 10- 50. The Z-dependence on the shakeoff probabilities so obtained has been represented by an analytical equation with two parameters. The formalism has been applied on a typical nuclear transfer reaction Fe5626 +C126 →Ni6028 +Be84 and it is found that electron shakeup, shakedown and shakeoff probabilities dominate for low l quantum number of the respective shells of the projectile-like fragment ion. However, for a particular value of l these processes show high probabilities for low values of n quantum number.

  3. Nuclear electric power for multimegawatt orbit transfer vehicles

    NASA Technical Reports Server (NTRS)

    Casagrande, R. D.

    1987-01-01

    Multimegawatt nuclear propulsion is an attractive option for orbit transfer vehicles. The masses of these platforms are expected to exceed the capability of a single launch from Earth necessitating assembly in space in a parking orbit. The OTV would transfer the platform from the parking orbit to the operational orbit and then return for the next mission. Electric propulsion is advantageous because of the high specific impulse achieved by the technology, 1000 to 5000 s and beyond, to reduce the propellant required. Nuclear power is attractive as the power system because of the weight savings over solar systems in the multimegawatt regime, and multimegawatts of power are required. A conceptual diagram is shown of an OTV with a command control module using electric thrusters powered from an SP-100 class nuclear reactor power system.

  4. Human Embryonic Stem Cells Derived by Somatic Cell Nuclear Transfer

    PubMed Central

    Tachibana, Masahito; Amato, Paula; Sparman, Michelle; Gutierrez, Nuria Marti; Tippner-Hedges, Rebecca; Ma, Hong; Kang, Eunju; Fulati, Alimujiang; Lee, Hyo-Sang; Sritanaudomchai, Hathaitip; Masterson, Keith; Larson, Janine; Eaton, Deborah; Sadler-Fredd, Karen; Battaglia, David; Lee, David; Wu, Diana; Jensen, Jeffrey; Patton, Phillip; Gokhale, Sumita; Stouffer, Richard L.; Wolf, Don; Mitalipov, Shoukhrat

    2013-01-01

    SUMMARY Reprogramming somatic cells into pluripotent embryonic stem cells (ESCs) by somatic cell nuclear transfer (SCNT) has been envisioned as an approach for generating patient-matched nuclear transfer (NT)-ESCs for studies of disease mechanisms and for developing specific therapies. Past attempts to produce human NT-ESCs have failed secondary to early embryonic arrest of SCNT embryos. Here, we identified premature exit from meiosis in human oocytes and suboptimal activation as key factors that are responsible for these outcomes. Optimized SCNT approaches designed to circumvent these limitations allowed derivation of human NT-ESCs. When applied to premium quality human oocytes, NT-ESC lines were derived from as few as two oocytes. NT-ESCs displayed normal diploid karyotypes and inherited their nuclear genome exclusively from parental somatic cells. Gene expression and differentiation profiles in human NT-ESCs were similar to embryo-derived ESCs, suggesting efficient reprogramming of somatic cells to a pluripotent state. PMID:23683578

  5. Measurement of heat transfer coefficients by nuclear magnetic resonance.

    PubMed

    Gultekin, David H; Gore, John C

    2008-11-01

    We demonstrate an experimental method for the measurement of heat transfer coefficient for a fluid system by magnetic resonance imaging. In this method, the temporal variation of thermally induced nuclear shielding is monitored and the average heat transfer coefficient is measured as a function of fluid velocity. We examine the cases of natural convection and forced convection at fluid velocity up to 0.8 m s(-1). These cases correspond to low dimensionless Biot (Bi) number where the heat transfer is limited by thermal convection. We demonstrate the NMR method for two simple geometries, a cylinder and a sphere, to experimentally determine the heat transfer coefficient (h) in two NMR imaging and spectroscopy systems through measuring three NMR parameters, the chemical shift, magnetization and spin self diffusion coefficient. PMID:18524523

  6. Nuclear transfer preserves the nuclear genome of freeze-dried mouse cells.

    PubMed

    Ono, Tetsuo; Mizutani, Eiji; Li, Chong; Wakayama, Teruhiko

    2008-12-01

    Mouse spermatozoa can be freeze dried without losing genetic integrity and reproductive potential. However, it is not known if freeze-dried mouse cells similarly maintain their genetic integrity and developmental potential following nuclear transfer. Here, we investigated the developmental capacity and embryonic stem (ES) cell derivation of reconstructed oocytes by nuclear transfer using freeze-dried cumulus or ES cells. Cumulus and ES cells were lyophilized overnight and stored at 4 C for up to 1 week. After rehydration, all cells showed membrane damage and were unviable. However, following nuclear transfer, 1-4% of the reconstructed oocytes developed to the blastocyst stage. A total of five nuclear transfer ES (ntES) cell lines were generated from blastocysts and morulae. All ntES cell lines had normal karyotypes and were positive for the ES-cell-specific markers (alkaline phosphatase, Oct3/4 and Nanog). After aggregation of ntES cells with fertilized embryos, chimeric mice with a high level of coat color chimerism were generated. Our findings show that the genomic integrity of cells can be maintained after freeze-drying and that it is possible to produce offspring from the cells using nuclear transfer techniques. PMID:18854641

  7. Heat Transfer Modeling of Dry Spent Nuclear Fuel Storage Facilities

    SciTech Connect

    Lee, S.Y.

    1999-01-13

    The present work was undertaken to provide heat transfer model that accurately predicts the thermal performance of dry spent nuclear fuel storage facilities. One of the storage configurations being considered for DOE Aluminum-clad Spent Nuclear Fuel (Al-SNF), such as the Material and Testing Reactor (MTR) fuel, is in a dry storage facility. To support design studies of storage options a computational and experimental program has been conducted at the Savannah River Site (SRS). The main objective is to develop heat transfer models including natural convection effects internal to an interim dry storage canister and to geological codisposal Waste Package (WP). Calculated temperatures will be used to demonstrate engineering viability of a dry storage option in enclosed interim storage and geological repository WP and to assess the chemical and physical behaviors of the Al-SNF in the dry storage facilities. The current paper describes the modeling approaches and presents the computational results along with the experimental data.

  8. Nuclear Effects in Neutrino Interactions at Low Momentum Transfer

    SciTech Connect

    Miltenberger, Ethan Ryan

    2015-05-01

    This is a study to identify predicted effects of the carbon nucleus environment on neutrino - nucleus interactions with low momentum transfer. A large sample of neutrino interaction data collected by the MINERvA experiment is analyzed to show the distribution of charged hadron energy in a region with low momentum transfer. These distributions reveal a major discrepancy between the data and a popular interaction model with only the simplest Fermi gas nuclear effects. Detailed analysis of systematic uncertainties due to energy scale and resolution can account for only a little of the discrepancy. Two additional nuclear model effects, a suppression/screening effect (RPA), and the addition of a meson exchange current process (MEC), are shown to improve the description of the data.

  9. Nuclear reactor fuel element having improved heat transfer

    DOEpatents

    Garnier, J.E.; Begej, S.; Williford, R.E.; Christensen, J.A.

    1982-03-03

    A nuclear reactor fuel element having improved heat transfer between fuel material and cladding is described. The element consists of an outer cladding tube divided into an upper fuel section containing a central core of fissionable or mixed fissionable and fertile fuel material, slightly smaller in diameter than the inner surface of the cladding tube and a small lower accumulator section, the cladding tube being which is filled with a low molecular weight gas to transfer heat from fuel material to cladding during irradiation. A plurality of essentially vertical grooves in the fuel section extend downward and communicate with the accumulator section. The radial depth of the grooves is sufficient to provide a thermal gradient between the hot fuel surface and the relatively cooler cladding surface to allow thermal segregation to take place between the low molecular weight heat transfer gas and high molecular weight fission product gases produced by the fuel material during irradiation.

  10. Nuclear reactor power for an electrically powered orbital transfer vehicle

    NASA Technical Reports Server (NTRS)

    Jaffe, L.; Beatty, R.; Bhandari, P.; Chow, E.; Deininger, W.; Ewell, R.; Fujita, T.; Grossman, M.; Kia, T.; Nesmith, B.

    1987-01-01

    To help determine the systems requirements for a 300-kWe space nuclear reactor power system, a mission and spacecraft have been examined which utilize electric propulsion and this nuclear reactor power for multiple transfers of cargo between low earth orbit (LEO) and geosynchronous earth orbit (GEO). A propulsion system employing ion thrusters and xenon propellant was selected. Propellant and thrusters are replaced after each sortie to GEO. The mass of the Orbital Transfer Vehicle (OTV), empty and dry, is 11,000 kg; nominal propellant load is 5000 kg. The OTV operates between a circular orbit at 925 km altitude, 28.5 deg inclination, and GEO. Cargo is brought to the OTV by Shuttle and an Orbital Maneuvering Vehicle (OMV); the OTV then takes it to GEO. The OTV can also bring cargo back from GEO, for transfer by OMV to the Shuttle. OTV propellant is resupplied and the ion thrusters are replaced by the OMV before each trip to GEO. At the end of mission life, the OTV's electric propulsion is used to place it in a heliocentric orbit so that the reactor will not return to earth. The nominal cargo capability to GEO is 6000 kg with a transit time of 120 days; 1350 kg can be transferred in 90 days, and 14,300 kg in 240 days. These capabilities can be considerably increased by using separate Shuttle launches to bring up propellant and cargo, or by changing to mercury propellant.

  11. Technological Transfer from Research Nuclear Reactors to New Generation Nuclear Power Reactors

    SciTech Connect

    Radulescu, Laura; Pavelescu, Margarit

    2010-01-21

    The goal of this paper is the analysis of the technological transfer role in the nuclear field, with particular emphasis on nuclear reactors domain. The presentation is sustained by historical arguments. In this frame, it is very important to start with the achievements of the first nuclear systems, for instant those with natural uranium as fuel and heavy water as moderator, following in time through the history until the New Generation Nuclear Power Reactors.Starting with 1940, the accelerated development of the industry has implied the increase of the global demand for energy. In this respect, the nuclear energy could play an important role, being essentially an unlimited source of energy. However, the nuclear option faces the challenges of increasingly demanding safety requirements, economic competitiveness and public acceptance. Worldwide, a significant amount of experience has been accumulated during development, licensing, construction, and operation of nuclear power reactors. The experience gained is a strong basis for further improvements. Actually, the nuclear programs of many countries are addressing the development of advanced reactors, which are intended to have better economics, higher reliability, improved safety, and proliferation-resistant characteristics in order to overcome the current concerns about nuclear power. Advanced reactors, now under development, may help to meet the demand for energy power of both developed and developing countries as well as for district heating, desalination and for process heat.The paper gives historical examples that illustrate the steps pursued from first research nuclear reactors to present advanced power reactors. Emphasis was laid upon the fact that the progress is due to the great discoveries of the nuclear scientists using the technological transfer.

  12. Method for somatic cell nuclear transfer in zebrafish.

    PubMed

    Siripattarapravat, K; Prukudom, S; Cibelli, J

    2016-01-01

    This chapter presents a detailed methodology for somatic cell nuclear transfer-cloning of zebrafish. We aim to place the reader in a virtual lab experience to assist acquisition of the technical skills required for reproducing the published protocol. All materials, including catalog numbers for reagents and techniques for their preparation, are provided. Our protocols describe laser inactivation of egg chromosomes, the transfer of a cell through the oocyte micropyle, and spontaneous activation of the reconstructed embryo. High-quality eggs are the key to cloning success, and Chinook salmon ovarian fluid is indispensable for keeping eggs arrested at the metaphase of meiosis II. This protocol continues to be refined by our laboratory. However, naive investigators should be able to apply it in its present form to generate cloned zebrafish. PMID:27443929

  13. Method for somatic cell nuclear transfer in zebrafish.

    PubMed

    Siripattarapravat, Kannika; Cibelli, Jose B

    2011-01-01

    Somatic cell nuclear transfer (SCNT) has been a well-known technique for decades and widely applied to generate identical animals, including ones with genetic alterations. The system has been demonstrated successfully in zebrafish. The elaborated requirements of SCNT, however, limit reproducibility of the established model to a few groups in zebrafish research community. In this chapter, we meticulously outline each step of the published protocol as well as preparations of equipments and reagents used in zebrafish SCNT. All describable detailed-tips are elaborated in texts and figures. PMID:21924165

  14. In vitro culture and somatic cell nuclear transfer affect imprinting of SNRPN gene in pre- and post-implantation stages of development in cattle

    PubMed Central

    Suzuki, Joao; Therrien, Jacinthe; Filion, France; Lefebvre, Rejean; Goff, Alan K; Smith, Lawrence C

    2009-01-01

    Background Embryo in vitro manipulations during early development are thought to increase mortality by altering the epigenetic regulation of some imprinted genes. Using a bovine interspecies model with a single nucleotide polymorphism, we assessed the imprinting status of the small nuclear ribonucleoprotein polypeptide N (SNRPN) gene in bovine embryos produced by artificial insemination (AI), in vitro culture (IVF) and somatic cell nuclear transfer (SCNT) and correlated allelic expression with the DNA methylation patterns of a differentially methylated region (DMR) located on the SNRPN promoter. Results In the AI group, SNRPN maternal expression is silenced at day 17 and 40 of development and a third of the alleles analyzed are methylated in the DMR. In the IVF group, maternal transcripts were identified at day 17 but methylation levels were similar to the AI group. However, day-40 fetuses in the IVF group showed significantly less methylation when compared to the AI group and SNRPN expression was mostly paternal in all fetal tissues studied, except in placenta. Finally, the SCNT group presented severe loss of DMR methylation in both day-17 embryos and 40 fetuses and biallelic expression was observed in all stages and tissues analyzed. Conclusion Together these results suggest that artificial reproductive techniques, such as prolonged in vitro culture and SCNT, lead to abnormal reprogramming of imprinting of SNRPN gene by altering methylation levels at this locus. PMID:19200381

  15. Propagation of elite rescue dogs by somatic cell nuclear transfer.

    PubMed

    Oh, Hyun Ju; Choi, Jin; Kim, Min Jung; Kim, Geon A; Jo, Young Kwang; Choi, Yoo Bin; Lee, Byeong Chun

    2016-01-01

    The objective of the present study was to compare the efficiency of two oocyte activation culture media to produce cloned dogs from an elite rescue dog and to analyze their behavioral tendencies. In somatic cell nuclear transfer procedure, fused couplets were activated by calcium ionophore treatment for 4 min, cultured in two media: modified synthetic oviduct fluid (mSOF) with 1.9 mmol/L 6-dimethylaminopyridine (DMAP) (SOF-DMAP) or porcine zygote medium (PZM-5) with 1.9 mmol/L DMAP (PZM-DMAP) for 4 h, and then were transferred into recipients. After embryo transfer, pregnancy was detected in one out of three surrogate mothers that received cloned embryos from the PZM-DMAP group (33.3%), and one pregnancy (25%) was detected in four surrogate mothers receiving cloned embryos from the SOF-DMAP group. Each pregnant dog gave birth to one healthy cloned puppy by cesarean section. We conducted the puppy aptitude test with two cloned puppies; the two cloned puppies were classified as the same type, accepting humans and leaders easily. The present study indicated that the type of medium used in 6-DMAP culture did not increase in cloning efficiency and dogs cloned using donor cells derived from one elite dog have similar behavioral tendencies. PMID:26387964

  16. Factors Affecting the Development of Somatic Cell Nuclear Transfer Embryos in Cattle

    PubMed Central

    AKAGI, Satoshi; MATSUKAWA, Kazutsugu; TAKAHASHI, Seiya

    2014-01-01

    Nuclear transfer is a complex multistep procedure that includes oocyte maturation, cell cycle synchronization of donor cells, enucleation, cell fusion, oocyte activation and embryo culture. Therefore, many factors are believed to contribute to the success of embryo development following nuclear transfer. Numerous attempts to improve cloning efficiency have been conducted since the birth of the first sheep by somatic cell nuclear transfer. However, the efficiency of somatic cell cloning has remained low, and applications have been limited. In this review, we discuss some of the factors that affect the developmental ability of somatic cell nuclear transfer embryos in cattle. PMID:25341701

  17. ICESluvan, a 94-Kilobase Mosaic Integrative Conjugative Element Conferring Interspecies Transfer of VanB-Type Glycopeptide Resistance, a Novel Bacitracin Resistance Locus, and a Toxin-Antitoxin Stabilization System

    PubMed Central

    Bjørkeng, Eva K.; Hjerde, Erik; Pedersen, Torunn; Sundsfjord, Arnfinn

    2013-01-01

    A 94-kb integrative conjugative element (ICESluvan) transferable to Enterococcus faecium and Enterococcus faecalis from an animal isolate of Streptococcus lutetiensis consists of a mosaic of genetic fragments from different Gram-positive bacteria. A variant of ICESluvan was confirmed in S. lutetiensis from a patient. A complete Tn5382/Tn1549 with a vanB2 operon is integrated into a streptococcal ICESde3396-like region harboring a putative bacteriophage exclusion system, a putative agglutinin receptor precursor, and key components of a type IV secretion system. Moreover, ICESluvan encodes a putative MobC family mobilization protein and a relaxase and, thus, in total has all genetic components essential for conjugative transfer. A 9-kb element within Tn5382/Tn1549 encodes, among others, putative proteins similar to the TnpX site-specific recombinase in Faecalibacterium and VanZ in Paenibacillus, which may contribute to the detected low-level teicoplanin resistance. Furthermore, ICESluvan encodes a novel bacitracin resistance locus that is associated with reduced susceptibility to bacitracin when transferred to E. faecium. The expression of a streptococcal pezAT toxin-antitoxin-encoding operon of ICESluvan in S. lutetiensis, E. faecium, and E. faecalis was confirmed by reverse transcription (RT)-PCR, indicating an active toxin-antitoxin system which may contribute to stabilizing ICESluvan within new hosts. Junction PCR and DNA sequencing confirmed that ICESluvan excised to form a circular intermediate in S. lutetiensis, E. faecalis, and E. faecium. Transfer between E. faecalis cells was observed in the presence of helper plasmid pIP964. Sequence analysis of the original S. lutetiensis donor and enterococcal transconjugants showed that ICESluvan integrates in a site-specific manner into the C-terminal end of the chromosomal tRNA methyltransferase gene rumA. PMID:24078615

  18. Interspecies Interactions within Oral Microbial Communities

    PubMed Central

    Kuramitsu, Howard K.; He, Xuesong; Lux, Renate; Anderson, Maxwell H.; Shi, Wenyuan

    2007-01-01

    Summary: While reductionism has greatly advanced microbiology in the past 400 years, assembly of smaller pieces just could not explain the whole! Modern microbiologists are learning “system thinking” and “holism.” Such an approach is changing our understanding of microbial physiology and our ability to diagnose/treat microbial infections. This review uses oral microbial communities as a focal point to describe this new trend. With the common name “dental plaque,” oral microbial communities are some of the most complex microbial floras in the human body, consisting of more than 700 different bacterial species. For a very long time, oral microbiologists endeavored to use reductionism to identify the key genes or key pathogens responsible for oral microbial pathogenesis. The limitations of reductionism forced scientists to begin adopting new strategies using emerging concepts such as interspecies interaction, microbial community, biofilms, polymicrobial disease, etc. These new research directions indicate that the whole is much more than the simple sum of its parts, since the interactions between different parts resulted in many new physiological functions which cannot be observed with individual components. This review describes some of these interesting interspecies-interaction scenarios. PMID:18063722

  19. HEAT TRANSFER ANALYSIS FOR NUCLEAR WASTE SOLIDIFICATION CONTAINER

    SciTech Connect

    Lee, S.

    2009-06-01

    The Nuclear Nonproliferation Programs Design Authority is in the design stage of the Waste Solidification Building (WSB) for the treatment and solidification of the radioactive liquid waste streams generated by the Pit Disassembly and Conversion Facility (PDCF) and Mixed Oxide (MOX) Fuel Fabrication Facility (MFFF). The waste streams will be mixed with a cementitious dry mix in a 55-gallon waste container. Savannah River National Laboratory (SRNL) has been performing the testing and evaluations to support technical decisions for the WSB. Engineering Modeling & Simulation Group was requested to evaluate the thermal performance of the 55-gallon drum containing hydration heat source associated with the current baseline cement waste form. A transient axi-symmetric heat transfer model for the drum partially filled with waste form cement has been developed and heat transfer calculations performed for the baseline design configurations. For this case, 65 percent of the drum volume was assumed to be filled with the waste form, which has transient hydration heat source, as one of the baseline conditions. A series of modeling calculations has been performed using a computational heat transfer approach. The baseline modeling results show that the time to reach the maximum temperature of the 65 percent filled drum is about 32 hours when a 43 C initial cement temperature is assumed to be cooled by natural convection with 27 C external air. In addition, the results computed by the present model were compared with analytical solutions. The modeling results will be benchmarked against the prototypic test results. The verified model will be used for the evaluation of the thermal performance for the WSB drum. Detailed results and the cases considered in the calculations will be discussed here.

  20. Gnotobiotic Miniature Pig Interbreed Somatic Cell Nuclear Transfer for Xenotransplantation.

    PubMed

    Hwang, Jeong Ho; Kim, Sang Eun; Gupta, Mukesh Kumar; Lee, HoonTaek

    2016-08-01

    Transgenic animal producing technology has improved consistently over the last couple of decades. Among the available methods, somatic cell nuclear transfer (SCNT) technology was officially the most popular. However, SCNT has low efficiency and requires a highly skilled individual. Additionally, the allo-SCNT nuclear reprogramming mechanism is poorly understood in the gnotobiotic miniature pig, which is a candidate for xenotransplantation, making sampling in oocytes very difficult compared to commercial hybrid pigs. Therefore, interbreed SCNT (ibSCNT), which is a combination of miniature pig and commercial pig (Landrace based), was analyzed and was found to be similar to SCNT in terms of the rate of blastocyst formation (12.6% ± 2.9% vs. 15.5% ± 2.2%; p > 0.05). However, a significantly lower fusion rate was observed in the ibSCNT compared to normal SCNT with Landrace pig somatic cells (29.6% ± 0.8% vs. 65.0% ± 4.9%). Thus, the optimization of fusion parameters was necessary for efficient SCNT. Our results further revealed that ibSCNT by the whole-cell intracytoplasmic injection (WCICI) method had a significantly higher blastocyst forming efficiency than the electrofusion method (31.1 ± 8.5 vs. 15.5% ± 2.2%). The nuclear remodeling and the pattern of changes in acetylation at H3K9 residue were similar in both SCNT and ibSCNT embryos. PMID:27459580

  1. Interspecies interactions and potential Influenza A virus risk in small swine farms in Peru

    PubMed Central

    2012-01-01

    Background The recent avian influenza epidemic in Asia and the H1N1 pandemic demonstrated that influenza A viruses pose a threat to global public health. The animal origins of the viruses confirmed the potential for interspecies transmission. Swine are hypothesized to be prime "mixing vessels" due to the dual receptivity of their trachea to human and avian strains. Additionally, avian and human influenza viruses have previously been isolated in swine. Therefore, understanding interspecies contact on smallholder swine farms and its potential role in the transmission of pathogens such as influenza virus is very important. Methods This qualitative study aimed to determine swine-associated interspecies contacts in two coastal areas of Peru. Direct observations were conducted at both small-scale confined and low-investment swine farms (n = 36) and in open areas where swine freely range during the day (n = 4). Interviews were also conducted with key stakeholders in swine farming. Results In both locations, the intermingling of swine and domestic birds was common. An unexpected contact with avian species was that swine were fed poultry mortality in 6/20 of the farms in Chancay. Human-swine contacts were common, with a higher frequency on the confined farms. Mixed farming of swine with chickens or ducks was observed in 36% of all farms. Human-avian interactions were less frequent overall. Use of adequate biosecurity and hygiene practices by farmers was suboptimal at both locations. Conclusions Close human-animal interaction, frequent interspecies contacts and suboptimal biosecurity and hygiene practices pose significant risks of interspecies influenza virus transmission. Farmers in small-scale swine production systems constitute a high-risk population and need to be recognized as key in preventing interspecies pathogen transfer. A two-pronged prevention approach, which offers educational activities for swine farmers about sound hygiene and biosecurity practices and

  2. Interspecies modeling of inhaled particle deposition patterns

    SciTech Connect

    Martonen, T.B.; Zhang, Z.; Yang, Y.

    1992-01-01

    To evaluate the potential toxic effects of ambient contaminants or therapeutic effects of airborne drugs, inhalation exposure experiments can be performed with surrogate laboratory animals. Herein, an interspecies particle deposition theory is presented for physiologically based pharmacokinetic modeling. It is derived to improve animal testing protocols. The computer code describes the behavior and fate of particles in the lungs of human subjects and a selected surrogate, the laboratory rat. In the simulations CO2 is integrated with exposure chamber atmospheres, and its concentrations regulated to produce rat breathing profiles corresponding to selected levels of human physical activity. The dosimetric model is used to calculate total, compartmental (i.e., tracheobronchial and pulmonary), and localized distribution patterns of inhaled particles in rats and humans for comparable ventilatory conditions. It is demonstrated that the model can be used to predetermine the exposure conditions necessary to produce deposition patterns in rats that are equivalent to those in humans at prescribed physical activities.

  3. Interspecies genetics of eating disorder traits.

    PubMed

    Kas, Martien J H; Kaye, Walter H; Foulds Mathes, Wendy; Bulik, Cynthia M

    2009-04-01

    Family and twin studies have indicated that genetic factors play a role in the development of eating disorders, such as anorexia and bulimia nervosa, but novel views and tools may enhance the identification of neurobiological mechanisms underlying these conditions. Here we propose an integrative genetic approach to reveal novel biological substrates of eating disorder traits analogous in mouse and human. For example, comparable to behavioral hyperactivity that is observed in 40-80% of anorexia nervosa patients, inbred strains of mice with different genetic backgrounds are differentially susceptible to develop behavioral hyperactivity when food restricted. In addition, a list of characteristics that are relevant to eating disorders and approaches to their measurement in humans together with potential analogous rodent models has been generated. Interspecies genetics of neurobehavioral characteristics of eating disorders has the potential to open new roads to identify and functionally test genetic pathways that influence neurocircuits relevant for these heterogeneous psychiatric disorders. PMID:18646037

  4. Nuclear remodeling in bovine somatic cell nuclear transfer embryos using MG132-treated recipient oocytes.

    PubMed

    Le Bourhis, Daniel; Beaujean, Nathalie; Ruffini, Sylvie; Vignon, Xavier; Gall, Laurence

    2010-12-01

    The early events in the nuclear reprogramming process during somatic cell nuclear transfer (SCNT) consist of morphological remodeling of the donor nucleus including premature chromosome condensation (PCC). In the present study, the objective was to increase oocyte M-Phase Promoting Factor (MPF) kinase activity and to examine the fate of the donor nucleus and the development of SCNT embryos thereafter. Indeed, in controls, recipient oocytes activated upon nuclear transfer, undergo a decrease in MPF activity, responsible for the inability to promote PCC in 77.8% of reconstituted embryos. Here we showed that exposure of the recipient oocyte to the proteasome inhibitor MG132 prior to fusion inhibited the degradation of cyclin B, which normally occurred immediately after activation by electro stimulation, and therefore sustained a high level of MPF. Treatment with MG132 also significantly increased the percentage of SCNT embryos with PCC when compared to the nontreated SCNT control embryos (94.1 vs. 22.2%, respectively, p < 0.01). The frequency of development to the blastocyst stage did not differ between MG132-treated or untreated recipient oocytes. However, we observed a significant increase of the total cells number in embryos produced after MG132 treatment. Investigation of the global nuclear organization by immunodetection of heterochromatin protein 1 (CBX1) showed that SCNT embryos derived from MG132-treated recipient oocytes displayed organization patterns similar to the ones observed in IVF embryos in contrast to the nontreated SCNT controls. Taken together, these results suggest that the PCC induced by MG132 treatment allows reorganization of the chromatin at an appropriate time potentially, leading to better reprogramming. PMID:21108537

  5. Natural convection heat transfer within horizontal spent nuclear fuel assemblies

    SciTech Connect

    Canaan, R.E.

    1995-12-01

    Natural convection heat transfer is experimentally investigated in an enclosed horizontal rod bundle, which characterizes a spent nuclear fuel assembly during dry storage and/or transport conditions. The basic test section consists of a square array of sixty-four stainless steel tubular heaters enclosed within a water-cooled rectangular copper heat exchanger. The heaters are supplied with a uniform power generation per unit length while the surrounding enclosure is maintained at a uniform temperature. The test section resides within a vacuum/pressure chamber in order to subject the assembly to a range of pressure statepoints and various backfill gases. The objective of this experimental study is to obtain convection correlations which can be used in order to easily incorporate convective effects into analytical models of horizontal spent fuel systems, and also to investigate the physical nature of natural convection in enclosed horizontal rod bundles in general. The resulting data consist of: (1) measured temperatures within the assembly as a function of power, pressure, and backfill gas; (2) the relative radiative contribution for the range of observed temperatures; (3) correlations of convective Nusselt number and Rayleigh number for the rod bundle as a whole; and (4) correlations of convective Nusselt number as a function of Rayleigh number for individual rods within the array.

  6. 10 CFR 73.28 - Security background checks for secure transfer of nuclear materials.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 2 2012-01-01 2012-01-01 false Security background checks for secure transfer of nuclear materials. 73.28 Section 73.28 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) PHYSICAL PROTECTION OF PLANTS AND MATERIALS Physical Protection of Special Nuclear Material in Transit § 73.28...

  7. 10 CFR 73.28 - Security background checks for secure transfer of nuclear materials.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 2 2013-01-01 2013-01-01 false Security background checks for secure transfer of nuclear materials. 73.28 Section 73.28 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) PHYSICAL PROTECTION OF PLANTS AND MATERIALS Physical Protection of Special Nuclear Material in Transit § 73.28...

  8. 10 CFR 73.28 - Security background checks for secure transfer of nuclear materials.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 2 2014-01-01 2014-01-01 false Security background checks for secure transfer of nuclear materials. 73.28 Section 73.28 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) PHYSICAL PROTECTION OF PLANTS AND MATERIALS Physical Protection of Special Nuclear Material in Transit § 73.28...

  9. 10 CFR 73.28 - Security background checks for secure transfer of nuclear materials.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 2 2011-01-01 2011-01-01 false Security background checks for secure transfer of nuclear materials. 73.28 Section 73.28 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) PHYSICAL PROTECTION OF PLANTS AND MATERIALS Physical Protection of Special Nuclear Material in Transit § 73.28...

  10. 10 CFR 73.28 - Security background checks for secure transfer of nuclear materials.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 2 2010-01-01 2010-01-01 false Security background checks for secure transfer of nuclear materials. 73.28 Section 73.28 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) PHYSICAL PROTECTION OF PLANTS AND MATERIALS Physical Protection of Special Nuclear Material in Transit § 73.28...

  11. Nuclear Technology Series. Course 4: Heat Transfer and Fluid Flow.

    ERIC Educational Resources Information Center

    Center for Occupational Research and Development, Inc., Waco, TX.

    This technical specialty course is one of thirty-five courses designed for use by two-year postsecondary institutions in five nuclear technician curriculum areas: (1) radiation protection technician, (2) nuclear instrumentation and control technician, (3) nuclear materials processing technician, (4) nuclear quality-assurance/quality-control…

  12. Histone deacetylase inhibitor improves the development and acetylation levels of cat-cow interspecies cloned embryos.

    PubMed

    Wittayarat, Manita; Sato, Yoko; Do, Lanh Thi Kim; Morita, Yasuhiro; Chatdarong, Kaywalee; Techakumphu, Mongkol; Taniguchi, Masayasu; Otoi, Takeshige

    2013-08-01

    Abnormal epigenetic reprogramming, such as histone acetylation, might cause low efficiency of interspecies somatic cell nuclear transfer (iSCNT). This study was conducted to evaluate the effects of trichostatin A (TSA) on the developmental competence and histone acetylation of iSCNT embryos reconstructed from cat somatic cells and bovine cytoplasm. The iSCNT cat and parthenogenetic bovine embryos were treated with various concentrations of TSA (0, 25, 50, or 100 nM) for 24 h, respectively, following fusion and activation. Treatment with 50 nM TSA produced significantly higher rates of cleavage and blastocyst formation (84.3% and 4.6%, respectively) of iSCNT embryos than the rates of non-TSA-treated iSCNT embryos (63.8% and 0%, respectively). Similarly, the treatment of 50 nM TSA increased the blastocyst formation rate of parthenogenetic bovine embryos. The acetylation levels of histone H3 lysine 9 (H3K9) in the iSCNT embryos with the treatment of 50 nM TSA were similar to those of in vitro-fertilized embryos and significantly higher (p<0.05) than those of non-TSA-treated iSCNT embryos (control), irrespective of the embryonic development stage (two-cell, four-cell, and eight-cell stages). These results indicated that the treatment of 50 nM TSA postfusion was beneficial for development to the blastocyst stage of iSCNT cat embryos and correlated with the increasing levels of acetylation at H3K9. PMID:23790014

  13. Assessing Uncertainty of Interspecies Correlation Estimation Models for Aromatic Compounds

    EPA Science Inventory

    We developed Interspecies Correlation Estimation (ICE) models for aromatic compounds containing 1 to 4 benzene rings to assess uncertainty in toxicity extrapolation in two data compilation approaches. ICE models are mathematical relationships between surrogate and predicted test ...

  14. Genome sequence of the lager brewing yeast, an interspecies hybrid.

    PubMed

    Nakao, Yoshihiro; Kanamori, Takeshi; Itoh, Takehiko; Kodama, Yukiko; Rainieri, Sandra; Nakamura, Norihisa; Shimonaga, Tomoko; Hattori, Masahira; Ashikari, Toshihiko

    2009-04-01

    This work presents the genome sequencing of the lager brewing yeast (Saccharomyces pastorianus) Weihenstephan 34/70, a strain widely used in lager beer brewing. The 25 Mb genome comprises two nuclear sub-genomes originating from Saccharomyces cerevisiae and Saccharomyces bayanus and one circular mitochondrial genome originating from S. bayanus. Thirty-six different types of chromosomes were found including eight chromosomes with translocations between the two sub-genomes, whose breakpoints are within the orthologous open reading frames. Several gene loci responsible for typical lager brewing yeast characteristics such as maltotriose uptake and sulfite production have been increased in number by chromosomal rearrangements. Despite an overall high degree of conservation of the synteny with S. cerevisiae and S. bayanus, the syntenies were not well conserved in the sub-telomeric regions that contain lager brewing yeast characteristic and specific genes. Deletion of larger chromosomal regions, a massive unilateral decrease of the ribosomal DNA cluster and bilateral truncations of over 60 genes reflect a post-hybridization evolution process. Truncations and deletions of less efficient maltose and maltotriose uptake genes may indicate the result of adaptation to brewing. The genome sequence of this interspecies hybrid yeast provides a new tool for better understanding of lager brewing yeast behavior in industrial beer production. PMID:19261625

  15. Cloned embryos from semen. Part 2: Intergeneric nuclear transfer of semen-derived eland (Taurotragus oryx) epithelial cells into bovine oocytes

    USGS Publications Warehouse

    Nel-Themaat, L.; Gomez, M.C.; Pope, C.E.; Lopez, M.; Wirtu, G.; Jenkins, J.A.; Cole, A.; Dresser, B.L.; Bondioli, K.R.; Godke, R.A.

    2008-01-01

    The production of cloned offspring by nuclear transfer (NT) of semen-derived somatic cells holds considerable potential for the incorporation of novel genes into endangered species populations. Because oocytes from endangered species are scarce, domestic species oocytes are often used as cytoplasts for interspecies NT. In the present study, epithelial cells isolated from eland semen were used for intergeneric transfer (IgNT) into enucleated bovine oocytes and compared with bovine NT embryos. Cleavage rates of bovine NT and eland IgNT embryos were similar (80 vs. 83%, respectively; p > 0.05); however, development to the morula and blastocyst stage was higher for bovine NT embryos (38 and 21%, respectively; p < 0.0001), than for eland IgNT embryos (0.5 and 0%, respectively). DNA synthesis was not observed in either bovine NT or eland IgNT cybrids before activation, but in 75 and 70% of bovine NT and eland igNT embryos, respectively, cell-cycle resumption was observed at 16 h postactivation (hpa). For eland IgNT embryos, 13% had ???8 cells at 84 hpa, while 32% of the bovine NT embryos had ???8 cells at the same interval. However, 100 and 66% of bovine NT and eland IgNT embryos, respectively, that had ???8 cells synthesized DNA. From these results we concluded that (1) semen-derived epithelial cell nuclei can interact and be transcriptionally controlled by bovine cytoplast, (2) the first cell-cycle occurred in IgNT embryos, (3) a high frequency of developmental arrest occurs before the eight-cell stage in IgNT embryos, and (4) IgNT embryos that progress through the early cleavage stage arrest can (a) synthesize DNA, (b) progress through subsequent cell cycles, and (c) may have the potential to develop further. ?? 2008 Mary Ann Liebert, Inc.

  16. Cloned embryos from semen. Part 2: intergeneric nuclear transfer of semen-derived eland (Taurotragus oryx) epithelial cells into bovine oocytes.

    PubMed

    Nel-Themaat, Liesl; Gómez, Martha C; Pope, C Earle; Lopez, Monica; Wirtu, Gemechu; Jenkins, Jill A; Cole, Alex; Dresser, Betsy L; Bondioli, Kenneth R; Godke, Robert A

    2008-03-01

    The production of cloned offspring by nuclear transfer (NT) of semen-derived somatic cells holds considerable potential for the incorporation of novel genes into endangered species populations. Because oocytes from endangered species are scarce, domestic species oocytes are often used as cytoplasts for interspecies NT. In the present study, epithelial cells isolated from eland semen were used for intergeneric transfer (IgNT) into enucleated bovine oocytes and compared with bovine NT embryos. Cleavage rates of bovine NT and eland IgNT embryos were similar (80 vs. 83%, respectively; p > 0.05); however, development to the morula and blastocyst stage was higher for bovine NT embryos (38 and 21%, respectively; p < 0.0001), than for eland IgNT embryos (0.5 and 0%, respectively). DNA synthesis was not observed in either bovine NT or eland IgNT cybrids before activation, but in 75 and 70% of bovine NT and eland igNT embryos, respectively, cell-cycle resumption was observed at 16 h postactivation (hpa). For eland IgNT embryos, 13% had > or = 8 cells at 84 hpa, while 32% of the bovine NT embryos had > or = 8 cells at the same interval. However, 100 and 66% of bovine NT and eland IgNT embryos, respectively, that had > or = 8 cells synthesized DNA. From these results we concluded that (1) semen-derived epithelial cell nuclei can interact and be transcriptionally controlled by bovine cytoplast, (2) the first cell-cycle occurred in IgNT embryos, (3) a high frequency of developmental arrest occurs before the eight-cell stage in IgNT embryos, and (4) IgNT embryos that progress through the early cleavage stage arrest can (a) synthesize DNA, (b) progress through subsequent cell cycles, and (c) may have the potential to develop further. PMID:18241126

  17. Heat Transfer Phenomena in Supercritical Water Nuclear Reactors

    SciTech Connect

    Mark H. Anderson; MichaelL. Corradini; Riccardo Bonazza; Jeremy R. Licht

    2007-10-03

    A supercritical water heat transfer facility has been built at the University of Wisconsin to study heat transfer in ancircular and square annular flow channel. A series of integral heat transfer measurements has been carried out over a wide range of heat flux, mas velocity and bulk water temperatures at a pressure of 25 MPa. The circular annular test section geometry is a 1.07 cm diameter heater rod within a 4.29 diameter flow channel.

  18. Molten Chloride Salts for Heat Transfer in Nuclear Systems

    NASA Astrophysics Data System (ADS)

    Ambrosek, James Wallace

    2011-12-01

    A forced convection loop was designed and constructed to examine the thermal-hydraulic performance of molten KCl-MgCl2 (68-32 at %) salt for use in nuclear co-generation facilities. As part of this research, methods for prediction of the thermo-physical properties of salt mixtures for selection of the coolant salt were studied. In addition, corrosion studies of 10 different alloys were exposed to the KCl-MgCl2 to determine a suitable construction material for the loop. Using experimental data found in literature for unary and binary salt systems, models were found, or developed to extrapolate the available experimental data to unstudied salt systems. These property models were then used to investigate the thermo-physical properties of the LINO3-NaNO3-KNO 3-Ca(NO3), system used in solar energy applications. Using these models, the density, viscosity, adiabatic compressibility, thermal conductivity, heat capacity, and melting temperatures of higher order systems can be approximated. These models may be applied to other molten salt systems. Coupons of 10 different alloys were exposed to the chloride salt for 100 hours at 850°C was undertaken to help determine with which alloy to construct the loop. Of the alloys exposed, Haynes 230 had the least amount of weight loss per area. Nickel and Hastelloy N performed best based on maximum depth of attack. Inconel 625 and 718 had a nearly uniform depletion of Cr from the surface of the sample. All other alloys tested had depletion of Cr along the grain boundaries. The Nb in Inconel 625 and 718 changed the way the Cr is depleted in these alloys. Grain-boundary engineering (GBE) of Incoloy 800H improved the corrosion resistance (weight loss and maximum depth of attack) by nearly 50% as compared to the as-received Incoloy 800H sample. A high temperature pump, thermal flow meter, and pressure differential device was designed, constructed and tested for use in the loop, The heat transfer of the molten chloride salt was found to

  19. Human somatic cell nuclear transfer and reproductive cloning: an Ethics Committee opinion.

    PubMed

    2016-04-01

    This document presents arguments that conclude that it is unethical to use somatic cell nuclear transfer (SCNT) for infertility treatment due to concerns about safety; the unknown impact of SCNT on children, families, and society; and the availability of other ethically acceptable means of assisted reproduction. This document replaces the ASRM Ethics Committee report titled, "Human somatic cell nuclear transfer and cloning," last published in Fertil Steril 2012;98:804-7. PMID:26746137

  20. Generation of cloned mice and nuclear transfer embryonic stem cell lines from urine-derived cells.

    PubMed

    Mizutani, Eiji; Torikai, Kohei; Wakayama, Sayaka; Nagatomo, Hiroaki; Ohinata, Yasuhide; Kishigami, Satoshi; Wakayama, Teruhiko

    2016-01-01

    Cloning animals by nuclear transfer provides the opportunity to preserve endangered mammalian species. However, there are risks associated with the collection of donor cells from the body such as accidental injury to or death of the animal. Here, we report the production of cloned mice from urine-derived cells collected noninvasively. Most of the urine-derived cells survived and were available as donors for nuclear transfer without any pretreatment. After nuclear transfer, 38-77% of the reconstructed embryos developed to the morula/blastocyst, in which the cell numbers in the inner cell mass and trophectoderm were similar to those of controls. Male and female cloned mice were delivered from cloned embryos transferred to recipient females, and these cloned animals grew to adulthood and delivered pups naturally when mated with each other. The results suggest that these cloned mice had normal fertility. In additional experiments, 26 nuclear transfer embryonic stem cell lines were established from 108 cloned blastocysts derived from four mouse strains including inbreds and F1 hybrids with relatively high success rates. Thus, cells derived from urine, which can be collected noninvasively, may be used in the rescue of endangered mammalian species by using nuclear transfer without causing injury to the animal. PMID:27033801

  1. Generation of cloned mice and nuclear transfer embryonic stem cell lines from urine-derived cells

    PubMed Central

    Mizutani, Eiji; Torikai, Kohei; Wakayama, Sayaka; Nagatomo, Hiroaki; Ohinata, Yasuhide; Kishigami, Satoshi; Wakayama, Teruhiko

    2016-01-01

    Cloning animals by nuclear transfer provides the opportunity to preserve endangered mammalian species. However, there are risks associated with the collection of donor cells from the body such as accidental injury to or death of the animal. Here, we report the production of cloned mice from urine-derived cells collected noninvasively. Most of the urine-derived cells survived and were available as donors for nuclear transfer without any pretreatment. After nuclear transfer, 38–77% of the reconstructed embryos developed to the morula/blastocyst, in which the cell numbers in the inner cell mass and trophectoderm were similar to those of controls. Male and female cloned mice were delivered from cloned embryos transferred to recipient females, and these cloned animals grew to adulthood and delivered pups naturally when mated with each other. The results suggest that these cloned mice had normal fertility. In additional experiments, 26 nuclear transfer embryonic stem cell lines were established from 108 cloned blastocysts derived from four mouse strains including inbreds and F1 hybrids with relatively high success rates. Thus, cells derived from urine, which can be collected noninvasively, may be used in the rescue of endangered mammalian species by using nuclear transfer without causing injury to the animal. PMID:27033801

  2. A background to nuclear transfer and its applications in agriculture and human therapeutic medicine*

    PubMed Central

    Campbell, Keith HS

    2002-01-01

    The development of a single celled fertilized zygote to an animal capable of reproduction involves not only cell division but the differentiation or specialization to numerous cell types forming each tissue and organ of the adult animal. The technique of nuclear transfer allows the reconstruction of an embryo by the transfer of genetic material from a single donor cell, to an unfertilized egg from which the genetic material has been removed. Successful development of live offspring from such embryos demonstrates that the differentiated state of the donor nucleus is not fixed and can be reprogrammed by the egg cytoplasm to control embryo and fetal development. Nuclear transfer has many applications in agriculture and human medicine. This article will review some of the factors associated with the success of embryo development following nuclear transfer and outline the potential uses of the technology. PMID:12033731

  3. Interspecies interactions are an integral determinant of microbial community dynamics

    PubMed Central

    Aziz, Fatma A. A.; Suzuki, Kenshi; Ohtaki, Akihiro; Sagegami, Keita; Hirai, Hidetaka; Seno, Jun; Mizuno, Naoko; Inuzuka, Yuma; Saito, Yasuhisa; Tashiro, Yosuke; Hiraishi, Akira; Futamata, Hiroyuki

    2015-01-01

    This study investigated the factors that determine the dynamics of bacterial communities in a complex system using multidisciplinary methods. Since natural and engineered microbial ecosystems are too complex to study, six types of synthetic microbial ecosystems (SMEs) were constructed under chemostat conditions with phenol as the sole carbon and energy source. Two to four phenol-degrading, phylogenetically and physiologically different bacterial strains were used in each SME. Phylogeny was based on the nucleotide sequence of 16S rRNA genes, while physiologic traits were based on kinetic and growth parameters on phenol. Two indices, J parameter and “interspecies interaction,” were compared to predict which strain would become dominant in an SME. The J parameter was calculated from kinetic and growth parameters. On the other hand, “interspecies interaction,” a new index proposed in this study, was evaluated by measuring the specific growth activity, which was determined on the basis of relative growth of a strain with or without the supernatant prepared from other bacterial cultures. Population densities of strains used in SMEs were enumerated by real-time quantitative PCR (qPCR) targeting the gene encoding the large subunit of phenol hydroxylase and were compared to predictions made from J parameter and interspecies interaction calculations. In 4 of 6 SEMs tested the final dominant strain shown by real-time qPCR analyses coincided with the strain predicted by both the J parameter and the interspecies interaction. However, in SMEII-2 and SMEII-3 the final dominant Variovorax strains coincided with prediction of the interspecies interaction but not the J parameter. These results demonstrate that the effects of interspecies interactions within microbial communities contribute to determining the dynamics of the microbial ecosystem. PMID:26539177

  4. Interspecies interactions are an integral determinant of microbial community dynamics.

    PubMed

    Aziz, Fatma A A; Suzuki, Kenshi; Ohtaki, Akihiro; Sagegami, Keita; Hirai, Hidetaka; Seno, Jun; Mizuno, Naoko; Inuzuka, Yuma; Saito, Yasuhisa; Tashiro, Yosuke; Hiraishi, Akira; Futamata, Hiroyuki

    2015-01-01

    This study investigated the factors that determine the dynamics of bacterial communities in a complex system using multidisciplinary methods. Since natural and engineered microbial ecosystems are too complex to study, six types of synthetic microbial ecosystems (SMEs) were constructed under chemostat conditions with phenol as the sole carbon and energy source. Two to four phenol-degrading, phylogenetically and physiologically different bacterial strains were used in each SME. Phylogeny was based on the nucleotide sequence of 16S rRNA genes, while physiologic traits were based on kinetic and growth parameters on phenol. Two indices, J parameter and "interspecies interaction," were compared to predict which strain would become dominant in an SME. The J parameter was calculated from kinetic and growth parameters. On the other hand, "interspecies interaction," a new index proposed in this study, was evaluated by measuring the specific growth activity, which was determined on the basis of relative growth of a strain with or without the supernatant prepared from other bacterial cultures. Population densities of strains used in SMEs were enumerated by real-time quantitative PCR (qPCR) targeting the gene encoding the large subunit of phenol hydroxylase and were compared to predictions made from J parameter and interspecies interaction calculations. In 4 of 6 SEMs tested the final dominant strain shown by real-time qPCR analyses coincided with the strain predicted by both the J parameter and the interspecies interaction. However, in SMEII-2 and SMEII-3 the final dominant Variovorax strains coincided with prediction of the interspecies interaction but not the J parameter. These results demonstrate that the effects of interspecies interactions within microbial communities contribute to determining the dynamics of the microbial ecosystem. PMID:26539177

  5. Thermoacoustic sensor for nuclear fuel temperaturemonitoring and heat transfer enhancement

    SciTech Connect

    James A. Smith; Dale K. Kotter; Randall A. Alli; Steven L. Garrett

    2013-05-01

    A new acoustical sensing system for the nuclear power industry has been developed at The Pennsylvania State University in collaboration with Idaho National Laboratories. This sensor uses the high temperatures of nuclear fuel to convert a nuclear fuel rod into a standing-wave thermoacoustic engine. When a standing wave is generated, the sound wave within the fuel rod will be propagated, by acoustic radiation, through the cooling fluid within the reactor or spent fuel pool and can be monitored a remote location external to the reactor. The frequency of the sound can be correlated to an effective temperature of either the fuel or the surrounding coolant. We will present results for a thermoacoustic resonator built into a Nitonic-60 (stainless steel) fuel rod that requires only one passive component and no heat exchangers.

  6. Ultrafast Charge Transfer of a Valence Double Hole in Glycine Driven Exclusively by Nuclear Motion

    NASA Astrophysics Data System (ADS)

    Li, Zheng; Vendrell, Oriol; Santra, Robin

    2015-10-01

    We explore theoretically the ultrafast transfer of a double electron hole between the functional groups of glycine after K -shell ionization and subsequent Auger decay. Although a large energy gap of about 15 eV initially exists between the two electronic states involved and coherent electronic dynamics play no role in the hole transfer, we find that the double hole is transferred within 3 to 4 fs between both functional ends of the glycine molecule driven solely by specific nuclear displacements and non-Born-Oppenheimer effects. The nuclear displacements along specific vibrational modes are of the order of 15% of a typical chemical bond between carbon, oxygen, and nitrogen atoms and about 30% for bonds involving hydrogen atoms. The time required for the hole transfer corresponds to less than half a vibrational period of the involved nuclear modes. This finding challenges the common wisdom that nuclear dynamics of the molecular skeleton are unimportant for charge transfer processes at the few-femtosecond time scale and shows that they can even play a prominent role. It also indicates that in x-ray imaging experiments, in which ionization is unavoidable, valence electron redistribution caused by nuclear dynamics might be much faster than previously anticipated. Thus, non-Born-Oppenheimer effects may affect the apparent electron densities extracted from such measurements.

  7. Fatal attraction: Explaining Russia's sensitive nuclear transfers to Iran

    NASA Astrophysics Data System (ADS)

    Kuchinsky, Leah R.

    This paper explores Russia's sensitive nuclear assistance to Iran in an effort to determine why a supplier state might proliferate against its own apparent security interests. The goal is to help readers understand the supply-side dynamics of nuclear proliferation. Through careful reconstruction of the historical narrative, using open source data, this study tests the plausibility of a "fatalistic calculus" explanation, identified by Stephen Sestanovich as a possible driver for Russia's behavior. According to the hypothesis, Russia has cooperated with Iran as a way both to stay in the good graces of a neighbor that is suspected of developing nuclear weapons and to win short-term influence and profits. The paper also examines the role of other factors advanced in the existing supply-side literature, such as economic motives identified by physicist and nonproliferation scholar David Albright. The findings show that bureaucratic, economic and fatalistic factors have each played a role in motivating Russia's cooperation with Iran, with their relative importance shifting over time. Fatalism begets a strategy of Russian "minimaxing," in the lexicon of Russia scholar Robert Freedman, wherein Russia attempts to minimize damage to its relationship with the U.S. while maximizing influence in Iran via nuclear cooperation. Fatalism, as actualized by minimaxing, best explains Russia's behavior after former Russian president Vladmir Putin came to power, when the bureaucratic and economic arguments become less cogent.

  8. Modeling transient heat transfer in nuclear waste repositories.

    PubMed

    Yang, Shaw-Yang; Yeh, Hund-Der

    2009-09-30

    The heat of high-level nuclear waste may be generated and released from a canister at final disposal sites. The waste heat may affect the engineering properties of waste canisters, buffers, and backfill material in the emplacement tunnel and the host rock. This study addresses the problem of the heat generated from the waste canister and analyzes the heat distribution between the buffer and the host rock, which is considered as a radial two-layer heat flux problem. A conceptual model is first constructed for the heat conduction in a nuclear waste repository and then mathematical equations are formulated for modeling heat flow distribution at repository sites. The Laplace transforms are employed to develop a solution for the temperature distributions in the buffer and the host rock in the Laplace domain, which is numerically inverted to the time-domain solution using the modified Crump method. The transient temperature distributions for both the single- and multi-borehole cases are simulated in the hypothetical geological repositories of nuclear waste. The results show that the temperature distributions in the thermal field are significantly affected by the decay heat of the waste canister, the thermal properties of the buffer and the host rock, the disposal spacing, and the thickness of the host rock at a nuclear waste repository. PMID:19376651

  9. Development of Interspecies Correlation Models for Petroleum Hydrocarbons

    EPA Science Inventory

    Estimating the consequences of petroleum products to water column organisms has commonly been hampered by limited acute toxicity data, which exists only for a relatively small number of test species. In this study, we developed petroleum-specific Interspecies Correlation Estimati...

  10. Single and Multi-Nucleon Transfer Reactions for Nuclear Moment Studies Toward Radioactive-Ion Beams

    SciTech Connect

    Lozeva, R. L.; Georgiev, G. P.; Audi, G.; Cabaret, S.; Fiori, E.; Gaulard, C.; Hauschilda, K.; Lopez-Martens, A.; Risegari, L.; Blazhev, A.; Jolie, J.; Moschner, K.; Zell, K.-O.; Daugas, J.-M.; Faul, T.; Morel, P.; Roig, O.; Ferraton, M.; Ibrahim, F.

    2010-04-30

    This study is a part of an experimental program to measure nuclear moments in transfer reactions. It aims to probe for a first time the nuclear -spin orientation in multi-nucleon transfer. Fist experiments were performed to measure the quadrupole moment of an isomeric state in {sup 66}Cu (I{sup p}i 6{sup -}, E{sub x} = 1154 keV, T{sub 1/2} = 595(20) ns) in single nucleon transfer and the population of mus isomers in {sup 66}Cu and {sup 63}Ni in multi-nucleon transfer. The experimentally tested methodology allows broad applications toward more exotic species and feasibility of these reactions to produce species away from stability.

  11. Treating humanity as an inviolable end: an analysis of contraception and altered nuclear transfer.

    PubMed

    Masek, Lawrence

    2008-04-01

    I argue that contraception is morally wrong but that periodic abstinence (or natural family planning) is not. Further, I argue that altered nuclear transfer -- a proposed technique for creating human stem cells without destroying human embryos -- is morally wrong for the same reason that contraception is. Contrary to what readers might expect, my argument assumes nothing about the morality of cloning or abortion and requires no premises about God or natural teleology. Instead, I argue that contraception and altered nuclear transfer are morally wrong because they fail to treat humanity as an inviolable end. PMID:18480499

  12. Activation of bovine somatic cell nuclear transfer embryos by PLCZ cRNA injection.

    PubMed

    Ross, Pablo J; Rodriguez, Ramon M; Iager, Amy E; Beyhan, Zeki; Wang, Kai; Ragina, Neli P; Yoon, Sook-Young; Fissore, Rafael A; Cibelli, Jose B

    2009-03-01

    The production of cloned animals by the transfer of a differentiated somatic cell into an enucleated oocyte circumvents fertilization. During fertilization, the sperm delivers a sperm-specific phospholipase C (PLCZ) that is responsible for triggering Ca(2)(+) oscillations and oocyte activation. During bovine somatic cell nuclear transfer (SCNT), oocyte activation is artificially achieved by combined chemical treatments that induce a monotonic rise in intracellular Ca(2)(+) and inhibit either phosphorylation or protein synthesis. In this study, we tested the hypothesis that activation of bovine nuclear transfer embryos by PLCZ improves nuclear reprogramming. Injection of PLCZ cRNA into bovine SCNT units induced Ca(2)(+) oscillations similar to those observed after fertilization and supported high rates of blastocyst development similar to that seen in embryos produced by IVF. Furthermore, gene expression analysis at the eight-cell and blastocyst stages revealed a similar expression pattern for a number of genes in both groups of embryos. Lastly, levels of trimethylated lysine 27 at histone H3 in blastocysts were higher in bovine nuclear transfer embryos activated using cycloheximide and 6-dimethylaminopurine (DMAP) than in those activated using PLCZ or derived from IVF. These results demonstrate that exogenous PLCZ can be used to activate bovine SCNT-derived embryos and support the hypothesis that a fertilization-like activation response can enhance some aspects of nuclear reprogramming. PMID:19074500

  13. One-two step transfer observed in 16O+11B nuclear system

    NASA Astrophysics Data System (ADS)

    Hamada, Sh.; Burtebayev, N.

    2015-06-01

    The angular distribution measurements for 16O ion beam elastically scattered from 11B target of thickness 32.9μg/cm2 at energy 22.4 MeV had been performed in the cyclotron DC-60 INP NNC RK. The previous measurements for 16O+11B nuclear system at energies 27, 30, 32.5 and 35 MeV showed an increase in the differential cross-section at backward angles due to the contribution of cluster transfer. Such transfer process could not be described in terms of optical model (OM); it could be described within the framework of distorted wave Born approximation method implemented in FRESCO code. Both one (5Li) and two-step transfer (proton transfer followed by Alpha transfer) were taken into considerations. We have extracted the spectroscopic amplitude (SA) for the configuration 16O→11B+5Li.

  14. Passive heat-transfer means for nuclear reactors. [LMFBR

    DOEpatents

    Burelbach, J.P.

    1982-06-10

    An improved passive cooling arrangement is disclosed for maintaining adjacent or related components of a nuclear reactor within specified temperature differences. Specifically, heat pipes are operatively interposed between the components, with the vaporizing section of the heat pipe proximate the hot component operable to cool it and the primary condensing section of the heat pipe proximate the other and cooler component operable to heat it. Each heat pipe further has a secondary condensing section that is located outwardly beyond the reactor confinement and in a secondary heat sink, such as air ambient the containment, that is cooler than the other reactor component. By having many such heat pipes, an emergency passive cooling system is defined that is operative without electrical power.

  15. Quantum state transfer between an optomechanical cavity and a diamond nuclear spin ensemble

    NASA Astrophysics Data System (ADS)

    Feng, Zhi-Bo; Wang, Hong-Ling; Yan, Run-Ying

    2016-08-01

    We explore an efficient scheme for transferring quantum state between an optomechanical cavity and nuclear spins of nitrogen-vacancy centers in diamond, where quantum information can be efficiently stored (retrieved) into (from) the nuclear spin ensemble assisted by a mechanical resonator in a dispersive regime. Our scheme works for a broad range of cavity frequencies and might have potential applications in employing the nuclear spin ensemble as a memory in quantum information processing. The feasibility of our protocol is analyzed using currently available parameters.

  16. Quantum state transfer between an optomechanical cavity and a diamond nuclear spin ensemble

    NASA Astrophysics Data System (ADS)

    Feng, Zhi-Bo; Wang, Hong-Ling; Yan, Run-Ying

    2016-05-01

    We explore an efficient scheme for transferring quantum state between an optomechanical cavity and nuclear spins of nitrogen-vacancy centers in diamond, where quantum information can be efficiently stored (retrieved) into (from) the nuclear spin ensemble assisted by a mechanical resonator in a dispersive regime. Our scheme works for a broad range of cavity frequencies and might have potential applications in employing the nuclear spin ensemble as a memory in quantum information processing. The feasibility of our protocol is analyzed using currently available parameters.

  17. 78 FR 67925 - Transfer of Real Property at Defense Nuclear Facilities for Economic Development

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-13

    ... process it will follow in the development of such regulations (65 FR 13735). DOE has examined today's rule...-AA82 Transfer of Real Property at Defense Nuclear Facilities for Economic Development AGENCY... final rule published on February 29, 2000, 65 FR 10685, as final, with changes. The final...

  18. Nucleologenesis and embryonic genome activation are defective in interspecies cloned embryos between bovine ooplasm and rhesus monkey somatic cells

    PubMed Central

    Song, Bong-Seok; Lee, Sang-Hee; Kim, Sun-Uk; Kim, Ji-Su; Park, Jung Sun; Kim, Cheol-Hee; Chang, Kyu-Tae; Han, Yong-Mahn; Lee, Kyung-Kwang; Lee, Dong-Seok; Koo, Deog-Bon

    2009-01-01

    Background Interspecies somatic cell nuclear transfer (iSCNT) has been proposed as a tool to address basic developmental questions and to improve the feasibility of cell therapy. However, the low efficiency of iSCNT embryonic development is a crucial problem when compared to in vitro fertilization (IVF) and intraspecies SCNT. Thus, we examined the effect of donor cell species on the early development of SCNT embryos after reconstruction with bovine ooplasm. Results No apparent difference in cleavage rate was found among IVF, monkey-bovine (MB)-iSCNT, and bovine-bovine (BB)-SCNT embryos. However, MB-iSCNT embryos failed to develop beyond the 8- or 16-cell stages and lacked expression of the genes involved in embryonic genome activation (EGA) at the 8-cell stage. From ultrastructural observations made during the peri-EGA period using transmission electron microscopy (TEM), we found that the nucleoli of MB-iSCNT embryos were morphologically abnormal or arrested at the primary stage of nucleologenesis. Consistent with the TEM analysis, nucleolar component proteins, such as upstream binding transcription factor, fibrillarin, nucleolin, and nucleophosmin, showed decreased expression and were structurally disorganized in MB-iSCNT embryos compared to IVF and BB-SCNT embryos, as revealed by real-time PCR and immunofluorescence confocal laser scanning microscopy, respectively. Conclusion The down-regulation of housekeeping and imprinting genes, abnormal nucleolar morphology, and aberrant patterns of nucleolar proteins during EGA resulted in developmental failure in MB-iSCNT embryos. These results provide insight into the unresolved problems of early embryonic development in iSCNT embryos. PMID:19635167

  19. Tie Tube Heat Transfer Modeling for Bimodal Nuclear Thermal Rockets

    SciTech Connect

    Clough, Joshua A.; Starkey, Ryan P.; Lewis, Mark J.; Lavelle, Thomas M.

    2007-01-30

    Bimodal nuclear thermal rocket systems have been shown to reduce the weight and cost of space vehicles to Mars and beyond by utilizing the reactor for power generation in the relatively long duration between burns in an interplanetary trajectory. No information, however, is available regarding engine and reactor-level operation of such bimodal systems. The purpose of this project is to generate engine and reactor models with sufficient fidelity and flexibility to accurately study the component-level effects of operating a propulsion-designed reactor at power generation levels. Previous development of a 1-D reactor and tie tube model found that ignoring heat generation inside of the tie tube leads to under-prediction of the temperature change and over-prediction of pressure change across the tie tube. This paper will present the development and results of a tie tube model that has been extended to account for heat generation, specifically in the moderator layer. This model is based on a 1-D distribution of power in the fuel elements and tie tubes, as a precursor to an eventual neutron-driven reactor model.

  20. 10 CFR 770.7 - What procedures are to be used to transfer real property at defense nuclear facilities for...

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 4 2014-01-01 2014-01-01 false What procedures are to be used to transfer real property at defense nuclear facilities for economic development? 770.7 Section 770.7 Energy DEPARTMENT OF ENERGY TRANSFER OF REAL PROPERTY AT DEFENSE NUCLEAR FACILITIES FOR ECONOMIC DEVELOPMENT § 770.7...

  1. 10 CFR 770.8 - May DOE transfer real property at defense nuclear facilities for economic development at less...

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 4 2012-01-01 2012-01-01 false May DOE transfer real property at defense nuclear facilities for economic development at less than fair market value? 770.8 Section 770.8 Energy DEPARTMENT OF ENERGY TRANSFER OF REAL PROPERTY AT DEFENSE NUCLEAR FACILITIES FOR ECONOMIC DEVELOPMENT § 770.8 May...

  2. 10 CFR 770.8 - May DOE transfer real property at defense nuclear facilities for economic development at less...

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 4 2014-01-01 2014-01-01 false May DOE transfer real property at defense nuclear facilities for economic development at less than fair market value? 770.8 Section 770.8 Energy DEPARTMENT OF ENERGY TRANSFER OF REAL PROPERTY AT DEFENSE NUCLEAR FACILITIES FOR ECONOMIC DEVELOPMENT § 770.8 May...

  3. 10 CFR 770.8 - May DOE transfer real property at defense nuclear facilities for economic development at less...

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 4 2013-01-01 2013-01-01 false May DOE transfer real property at defense nuclear facilities for economic development at less than fair market value? 770.8 Section 770.8 Energy DEPARTMENT OF ENERGY TRANSFER OF REAL PROPERTY AT DEFENSE NUCLEAR FACILITIES FOR ECONOMIC DEVELOPMENT § 770.8 May...

  4. 10 CFR 770.8 - May DOE transfer real property at defense nuclear facilities for economic development at less...

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 4 2010-01-01 2010-01-01 false May DOE transfer real property at defense nuclear facilities for economic development at less than fair market value? 770.8 Section 770.8 Energy DEPARTMENT OF ENERGY TRANSFER OF REAL PROPERTY AT DEFENSE NUCLEAR FACILITIES FOR ECONOMIC DEVELOPMENT § 770.8 May...

  5. 10 CFR 770.8 - May DOE transfer real property at defense nuclear facilities for economic development at less...

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 4 2011-01-01 2011-01-01 false May DOE transfer real property at defense nuclear facilities for economic development at less than fair market value? 770.8 Section 770.8 Energy DEPARTMENT OF ENERGY TRANSFER OF REAL PROPERTY AT DEFENSE NUCLEAR FACILITIES FOR ECONOMIC DEVELOPMENT § 770.8 May...

  6. High-fidelity transfer and storage of photon states in a single nuclear spin

    NASA Astrophysics Data System (ADS)

    Yang, Sen; Wang, Ya; Rao, D. D. Bhaktavatsala; Hien Tran, Thai; Momenzadeh, Ali S.; Markham, M.; Twitchen, D. J.; Wang, Ping; Yang, Wen; Stöhr, Rainer; Neumann, Philipp; Kosaka, Hideo; Wrachtrup, Jörg

    2016-08-01

    Long-distance quantum communication requires photons and quantum nodes that comprise qubits for interaction with light and good memory capabilities, as well as processing qubits for the storage and manipulation of photons. Owing to the unavoidable photon losses, robust quantum communication over lossy transmission channels requires quantum repeater networks. A necessary and highly demanding prerequisite for these networks is the existence of quantum memories with long coherence times to reliably store the incident photon states. Here we demonstrate the high-fidelity (∼98%) coherent transfer of a photon polarization state to a single solid-state nuclear spin that has a coherence time of over 10 s. The storage process is achieved by coherently transferring the polarization state of a photon to an entangled electron–nuclear spin state of a nitrogen–vacancy centre in diamond. The nuclear spin-based optical quantum memory demonstrated here paves the way towards an absorption-based quantum repeater network.

  7. Modularization and nuclear power. Report by the Technology Transfer Modularization Task Team

    SciTech Connect

    Not Available

    1985-06-01

    This report describes the results of the work performed by the Technology Transfer Task Team on Modularization. This work was performed as part of the Technology Transfer work being performed under Department of Energy Contract 54-7WM-335406, between December, 1984 and February, 1985. The purpose of this task team effort was to briefly survey the current use of modularization in the nuclear and non-nuclear industries and to assess and evaluate the techniques available for potential application to nuclear power. A key conclusion of the evaluation was that there was a need for a study to establish guidelines for the future development of Light Water Reactor, High Temperature Gas Reactor and Liquid Metal Reactor plants. The guidelines should identify how modularization can improve construction, maintenance, life extension and decommissioning.

  8. Explaining dehumanization among children: the interspecies model of prejudice.

    PubMed

    Costello, Kimberly; Hodson, Gordon

    2014-03-01

    Although many theoretical approaches have emerged to explain prejudices expressed by children, none incorporate outgroup dehumanization, a key predictor of prejudice among adults. According to the Interspecies Model of Prejudice, beliefs in the human-animal divide facilitate outgroup prejudice through fostering animalistic dehumanization (Costello & Hodson, 2010). In the present investigation, White children attributed Black children fewer 'uniquely human' characteristics, representing the first systematic evidence of racial dehumanization among children (Studies 1 and 2). In Study 2, path analyses supported the Interspecies Model of Prejudice: children's human-animal divide beliefs predicted greater racial prejudice, an effect explained by heightened racial dehumanization. Similar patterns emerged among parents. Furthermore, parent Social Dominance Orientation predicted child prejudice indirectly through children's endorsement of a hierarchical human-animal divide and subsequent dehumanizing tendencies. Encouragingly, children's human-animal divide perceptions were malleable to an experimental prime highlighting animal-human similarity. Implications for prejudice interventions are considered. PMID:23083220

  9. Critical issues in intra- and interspecies dosimetry of ozone

    SciTech Connect

    Miller, F.J.; Overton, J.H.

    1989-01-01

    Knowledge of dose at the target site is a fundamental starting point in making interspecies dosimetric comparisons. To the extent that information is available on the effective dose of a compound, the confidence in risk assessments is increased. To facilitate judgments about effects determined in animals relative to likelihood of risk associated with human exposure to ozone (O3), a mathematical dosimetry model has been developed for interspecies comparisons. The model incorporates the major factors affecting the absorption of O3 in the respiratory tract: the morphology of the respiratory tract, the route, depth and rate of breathing, physicochemical properties of O3, the physical and chemical processes which govern gas transport, and the physicochemical properties of the lining fluids and tissue material of the airways and gas exchange units. Also discussed are the application of the dosimetry model for examining age-dependent susceptibility to O3 and the potential usefulness of such models for relating microdosimetry to microtoxicology.

  10. Mammalian interspecies substitution of immune modulatory alleles by genome editing

    PubMed Central

    Lillico, Simon G.; Proudfoot, Chris; King, Tim J.; Tan, Wenfang; Zhang, Lei; Mardjuki, Rachel; Paschon, David E.; Rebar, Edward J.; Urnov, Fyodor D.; Mileham, Alan J.; McLaren, David G.; Whitelaw, C. Bruce A.

    2016-01-01

    We describe a fundamentally novel feat of animal genetic engineering: the precise and efficient substitution of an agronomic haplotype into a domesticated species. Zinc finger nuclease in-embryo editing of the RELA locus generated live born domestic pigs with the warthog RELA orthologue, associated with resilience to African Swine Fever. The ability to efficiently achieve interspecies allele introgression in one generation opens unprecedented opportunities for agriculture and basic research. PMID:26898342

  11. Mammalian interspecies substitution of immune modulatory alleles by genome editing.

    PubMed

    Lillico, Simon G; Proudfoot, Chris; King, Tim J; Tan, Wenfang; Zhang, Lei; Mardjuki, Rachel; Paschon, David E; Rebar, Edward J; Urnov, Fyodor D; Mileham, Alan J; McLaren, David G; Whitelaw, C Bruce A

    2016-01-01

    We describe a fundamentally novel feat of animal genetic engineering: the precise and efficient substitution of an agronomic haplotype into a domesticated species. Zinc finger nuclease in-embryo editing of the RELA locus generated live born domestic pigs with the warthog RELA orthologue, associated with resilience to African Swine Fever. The ability to efficiently achieve interspecies allele introgression in one generation opens unprecedented opportunities for agriculture and basic research. PMID:26898342

  12. 10 CFR 770.7 - What procedures are to be used to transfer real property at defense nuclear facilities for...

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 4 2011-01-01 2011-01-01 false What procedures are to be used to transfer real property... ENERGY TRANSFER OF REAL PROPERTY AT DEFENSE NUCLEAR FACILITIES FOR ECONOMIC DEVELOPMENT § 770.7 What... congressional defense committees through the Secretary of Energy. (d) Transfer. After the...

  13. 10 CFR 770.7 - What procedures are to be used to transfer real property at defense nuclear facilities for...

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 4 2013-01-01 2013-01-01 false What procedures are to be used to transfer real property... ENERGY TRANSFER OF REAL PROPERTY AT DEFENSE NUCLEAR FACILITIES FOR ECONOMIC DEVELOPMENT § 770.7 What... congressional defense committees through the Secretary of Energy. (d) Transfer. After the...

  14. 10 CFR 770.7 - What procedures are to be used to transfer real property at defense nuclear facilities for...

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 4 2010-01-01 2010-01-01 false What procedures are to be used to transfer real property... ENERGY TRANSFER OF REAL PROPERTY AT DEFENSE NUCLEAR FACILITIES FOR ECONOMIC DEVELOPMENT § 770.7 What... congressional defense committees through the Secretary of Energy. (d) Transfer. After the...

  15. 10 CFR 770.7 - What procedures are to be used to transfer real property at defense nuclear facilities for...

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 4 2012-01-01 2012-01-01 false What procedures are to be used to transfer real property... ENERGY TRANSFER OF REAL PROPERTY AT DEFENSE NUCLEAR FACILITIES FOR ECONOMIC DEVELOPMENT § 770.7 What... congressional defense committees through the Secretary of Energy. (d) Transfer. After the...

  16. Mechanisms Underlying Mammalian Hybrid Sterility in Two Feline Interspecies Models.

    PubMed

    Davis, Brian W; Seabury, Christopher M; Brashear, Wesley A; Li, Gang; Roelke-Parker, Melody; Murphy, William J

    2015-10-01

    The phenomenon of male sterility in interspecies hybrids has been observed for over a century, however, few genes influencing this recurrent phenotype have been identified. Genetic investigations have been primarily limited to a small number of model organisms, thus limiting our understanding of the underlying molecular basis of this well-documented "rule of speciation." We utilized two interspecies hybrid cat breeds in a genome-wide association study employing the Illumina 63 K single-nucleotide polymorphism array. Collectively, we identified eight autosomal genes/gene regions underlying associations with hybrid male sterility (HMS) involved in the function of the blood-testis barrier, gamete structural development, and transcriptional regulation. We also identified several candidate hybrid sterility regions on the X chromosome, with most residing in close proximity to complex duplicated regions. Differential gene expression analyses revealed significant chromosome-wide upregulation of X chromosome transcripts in testes of sterile hybrids, which were enriched for genes involved in chromatin regulation of gene expression. Our expression results parallel those reported in Mus hybrids, supporting the "Large X-Effect" in mammalian HMS and the potential epigenetic basis for this phenomenon. These results support the value of the interspecies feline model as a powerful tool for comparison to rodent models of HMS, demonstrating unique aspects and potential commonalities that underpin mammalian reproductive isolation. PMID:26006188

  17. Significant improvement of mouse cloning technique by treatment with trichostatin A after somatic nuclear transfer

    SciTech Connect

    Kishigami, Satoshi . E-mail: kishigami@cdb.riken.jp; Mizutani, Eiji; Ohta, Hiroshi; Hikichi, Takafusa; Thuan, Nguyen Van; Wakayama, Sayaka; Bui, Hong-Thuy; Wakayama, Teruhiko

    2006-02-03

    The low success rate of animal cloning by somatic cell nuclear transfer (SCNT) is believed to be associated with epigenetic errors including abnormal DNA hypermethylation. Recently, we elucidated by using round spermatids that, after nuclear transfer, treatment of zygotes with trichostatin A (TSA), an inhibitor of histone deacetylase, can remarkably reduce abnormal DNA hypermethylation depending on the origins of transferred nuclei and their genomic regions [S. Kishigami, N. Van Thuan, T. Hikichi, H. Ohta, S. Wakayama. E. Mizutani, T. Wakayama, Epigenetic abnormalities of the mouse paternal zygotic genome associated with microinsemination of round spermatids, Dev. Biol. (2005) in press]. Here, we found that 5-50 nM TSA-treatment for 10 h following oocyte activation resulted in more efficient in vitro development of somatic cloned embryos to the blastocyst stage from 2- to 5-fold depending on the donor cells including tail tip cells, spleen cells, neural stem cells, and cumulus cells. This TSA-treatment also led to more than 5-fold increase in success rate of mouse cloning from cumulus cells without obvious abnormality but failed to improve ES cloning success. Further, we succeeded in establishment of nuclear transfer-embryonic stem (NT-ES) cells from TSA-treated cloned blastocyst at a rate three times higher than those from untreated cloned blastocysts. Thus, our data indicate that TSA-treatment after SCNT in mice can dramatically improve the practical application of current cloning techniques.

  18. Intra- and inter-species spread of carbapenemase genes in a non-hospitalized patient.

    PubMed

    Sorlí, L; Miró, E; Segura, C; Navarro, F; Grau, S; Salvado, M; Horcajada, J P

    2011-12-01

    The purpose of this study was to report intra- and inter-species spread of carbapenemase genes between gram negative rods isolated from a non-hospitalized patient with bacteremia. The approach included chart review, antibiotic susceptibility testing and phenotypic screening for metallo-β-lactamase (MBL) detection, PCR and sequencing of bla, aac(6')-Ib and qnr genes, and plasmid analysis by PCR-based replicon typing. The clonal relationships between the isolates were analysed by comparing PFGE profiles. A non-hospitalized patient presented bacteraemia due to wild type Enterobacter cloacae (4.08), a VIM-1-producing E. cloacae (5.08), a VIM-1- and CTX-M-9-producing E. cloacae (7.08), a VIM-2-producing Pseudomonas aeruginosa, and catheter colonization by VIM-1-producing Klebsiella oxytoca. The patient had no previous hospitalization but had recently undergone an ambulatory colonoscopy. In E. cloacae 7.08 and K. oxytoca isolates, the bla(VIM-1) gene was located on a transferable plasmid of 48.5 kb, while in E. cloacae 5.08 the bla(VIM-1) gene was encoded on a 194 kb non-transferable plasmid. The bla(CTX-M-9) gene detected in E. cloacae was encoded on an HI2 plasmid of 290 kb. To date the prevalence of VIM-1 enzymes in the community is low. This molecular finding suggests an intra-species and/or inter-species horizontal spread of the MBL gene in the same non-hospitalized patient. PMID:21491175

  19. Control of interspecies electron flow during anaerobic digestion: role of floc formation in syntrophic methanogenesis

    SciTech Connect

    Thiele, J.H.; Chartrain, M.; Zeikus, J.G.

    1988-01-01

    The flora of an anaerobic whey-processing chemostat was separated by anaerobic sedimentation techniques into a free-living bacterial fraction and a bacterial floc fraction. The floc fraction constituted a major part (i.e., 57% total protein) of the total microbial population in the digestor, and it accounted for 87% of the total CO/sub 2/-dependent methanogenic activity and 76% of the total ethanol-consuming acetogenic activity. Lactose was degraded by both cellular fractions, but in the free flora fraction it was associated with higher intermediary levels of H/sub 2/, ethanol, butyrate, and propionate production. Electron microscopic analysis of flocs showed bacterial diversity and juxtapositioning of tentative Desulfovibrio and Methanobacterium species without significant microcolony formation. Ethanol, an intermediary product of lactose-hydrolyzing bacteria, was converted to acetate and methane within the flocs by interspecies electron transfer. Ethanol-dependent methane formation was compartmentalized and closely coupled kinetically within the flocs but without significant formation of H/sub 2/ gas. Physical disruption of flocs into fragments of 10- to 20-..mu..m diameter initially increased the H/sub 2/ partial pressure but did not change the carbon transformation kinetic patterns of ethanol metabolism or demonstrate a significant role for H/sub 2/ in CO/sub 2/ reduction to methane. The data demonstrate that floc formation in a whey-processing anaerobic digestor functions in juxtapositioning cells for interspecies electron transfer during syntrophic ethanol conversion into acetate and methane but by a mechanism which was independent of the available dissolved H/sub 2/ gas pool in the ecosystem.

  20. Molecular and biological aspects of early germ cell development in interspecies hybrids between chickens and pheasants.

    PubMed

    Kang, Seok Jin; Sohn, Sea Hwan; Kang, Kyung Soo; Lee, Hyung Chul; Lee, Seul Ki; Choi, Jin Won; Han, Jae Yong

    2011-03-01

    Interspecific hybrids provide insights into fundamental genetic principles, and may prove useful for biotechnological applications and as tools for the conservation of endangered species. In the present study, interspecies hybrids were generated between the Korean ring-necked pheasant (Phasianus colchicus) and the White Leghorn chicken (Gallus gallus domesticus). We determined whether these hybrids were good recipients for the production of germline chimeric birds. PCR-based species-specific amplification and karyotype analyses showed that the hybrids inherited genetic material from both parents. Evaluation of biological function indicated that the growth rates of hybrids during the exponential phase (body weight/week) were similar to those of the pheasant but not the chicken, and that the incubation period for hatching was significantly different from that of both parents. Primordial germ cells (PGCs) of hybrids reacted with a pheasant PGC-specific antibody and circulated normally in blood vessels. The peak time of hybrid PGC migration was equivalent to that of the pheasant. In late embryonic stages, germ cells were detected by the QCR1 antibody on 15 d male gonads and were normally localized in the seminiferous cords. We examined the migration ability and developmental localization of exogenous PGCs transferred into the blood vessels of 63 h hybrid embryos. Donor-derived PGCs reacted with a donor-specific antibody were detected on 7 d gonads and the seminiferous tubules of hatchlings. Therefore, germ cell transfer into developing embryos of an interspecies hybrid can be efficiently used for the conservation of threatened animals and endangered species, and many biotechnological applications. PMID:21111472

  1. Cytoskeletal to Nuclear Strain Transfer Regulates YAP Signaling in Mesenchymal Stem Cells

    PubMed Central

    Driscoll, Tristan P.; Cosgrove, Brian D.; Heo, Su-Jin; Shurden, Zach E.; Mauck, Robert L.

    2015-01-01

    Mechanical forces transduced to cells through the extracellular matrix are critical regulators of tissue development, growth, and homeostasis, and can play important roles in directing stem cell differentiation. In addition to force-sensing mechanisms that reside at the cell surface, there is growing evidence that forces transmitted through the cytoskeleton and to the nuclear envelope are important for mechanosensing, including activation of the Yes-associated protein (YAP)/transcriptional coactivator with PDZ-binding motif (TAZ) pathway. Moreover, nuclear shape, mechanics, and deformability change with differentiation state and have been likewise implicated in force sensing and differentiation. However, the significance of force transfer to the nucleus through the mechanosensing cytoskeletal machinery in the regulation of mesenchymal stem cell mechanobiologic response remains unclear. Here we report that actomyosin-generated cytoskeletal tension regulates nuclear shape and force transmission through the cytoskeleton and demonstrate the differential short- and long-term response of mesenchymal stem cells to dynamic tensile loading based on the contractility state, the patency of the actin cytoskeleton, and the connections it makes with the nucleus. Specifically, we show that while some mechanoactive signaling pathways (e.g., ERK signaling) can be activated in the absence of nuclear strain transfer, cytoskeletal strain transfer to the nucleus is essential for activation of the YAP/TAZ pathway with stretch. PMID:26083918

  2. Polarization Transfer from Ligands Hyperpolarized by Dissolution Dynamic Nuclear Polarization for Screening in Drug Discovery.

    PubMed

    Min, Hlaing; Sekar, Giridhar; Hilty, Christian

    2015-09-01

    Nuclear magnetic resonance (NMR) spectroscopy is a valuable technique for ligand screening, because it exhibits high specificity toward chemical structure and interactions. Dissolution dynamic nuclear polarization (DNP) is a recent advance in NMR methodology that enables the creation of non-equilibrium spin states, which can dramatically increase NMR sensitivity. Here, the transfer of such spin polarization from hyperpolarized ligand to protein is observed. Mixing hyperpolarized benzamidine with the serine protease trypsin, a "fingerprint" of enhanced protein signals is observed, which shows a different intensity profile than the equilibrium NMR spectrum of the protein, but coincides closely to the frequency profile of a saturation transfer difference (STD) NMR experiment. The DNP experiment benefits from hyperpolarization and enables observation of all frequencies in a single, rapid experiment. Based on these merits, it is an interesting alternative to the widely used STD experiment for identification of protein-ligand interactions. PMID:26315550

  3. Ion engine propelled Earth-Mars cycler with nuclear thermal propelled transfer vehicle, volume 2

    NASA Technical Reports Server (NTRS)

    Meyer, Rudolf X.; Baker, Myles; Melko, Joseph

    1994-01-01

    The goal of this project was to perform a preliminary design of a long term, reusable transportation system between earth and Mars which would be capable of providing both artificial gravity and shelter from solar flare radiation. The heart of this system was assumed to be a Cycler spacecraft propelled by an ion propulsion system. The crew transfer vehicle was designed to be propelled by a nuclear-thermal propulsion system. Several Mars transportation system architectures and their associated space vehicles were designed.

  4. Neutron Transfer Reactions: Surrogates for Neutron Capture for Basic and Applied Nuclear Science

    SciTech Connect

    Cizewski, J. A.; Peters, W. A.; Allen, J.; Hatarik, R.; Matthews, C.; O'Malley, P.; Jones, K. L.; Kozub, R. L.; Howard, J.; Patterson, N.; Paulauskas, S. V.; Rogers, J.; Sissom, D. J.; Pain, S. D.; Adekola, A.; Bardayan, D. W.; Blackmon, J. C.; Liang, F.; Nesaraja, C. D.; Pittman, S. T.

    2009-03-10

    Neutron capture reactions on unstable nuclei are important for both basic and applied nuclear science. A program has been developed at the Holifield Radioactive Ion Beam Facility at Oak Ridge National Laboratory to study single-neutron transfer (d,p) reactions with rare isotope beams to provide information on neutron-induced reactions on unstable nuclei. Results from (d,p) studies on {sup 130,132}Sn, {sup 134}Te and {sup 75}As are discussed.

  5. Neutron transfer reactions: Surrogates for neutron capture for basic and applied nuclear science

    SciTech Connect

    Cizewski, J. A.; Jones, K. L.; Kozub, R. L.; Pain, Steven D; Peters, W. A.; Adekola, Aderemi S; Allen, J.; Bardayan, Daniel W; Becker, J.; Blackmon, Jeff C; Chae, K. Y.; Chipps, K.; Erikson, Luke; Gaddis, A. L.; Harlin, Christopher W; Hatarik, Robert; Howard, Joshua A; Jandel, M.; Johnson, Micah; Kapler, R.; Krolas, W.; Liang, J Felix; Livesay, Jake; Ma, Zhanwen; Matei, Catalin; Matthews, C.; Moazen, Brian; Nesaraja, Caroline D; O'Malley, Patrick; Patterson, N. P.; Paulauskas, Stanley; Pelham, T.; Pittman, S. T.; Radford, David C; Rogers, J.; Schmitt, Kyle; Shapira, Dan; ShrinerJr., J. F.; Sissom, D. J.; Smith, Michael Scott; Swan, T. P.; Thomas, J. S.; Vieira, D. J.; Wilhelmy, J. B.; Wilson, Gemma L

    2009-04-01

    Neutron capture reactions on unstable nuclei are important for both basic and applied nuclear science. A program has been developed at the Holifield Radioactive Ion Beam Facility at Oak Ridge National Laboratory to study single-neutron transfer (d,p) reactions with rare isotope beams to provide information on neutron-induced reactions on unstable nuclei. Results from (d,p) studies on {sup 130,132}Sn, {sup 134}Te and {sup 75}As are discussed.

  6. An inter-subspecies cloned buffalo (Bubalus bubalis) obtained by transferring of cryopreserved embryos via somatic cell nuclear transfer.

    PubMed

    Yang, B Z; Yang, C Y; Li, R C; Qin, G S; Zhang, X F; Pang, C Y; Chen, M T; Huang, F X; Li, Z; Zheng, H Y; Huang, Y J; Liang, X W

    2010-10-01

    The aim of this study was to explore the feasibility of cryopreservation of inter-subspecies cloned embryos in buffalo. In our experiment, river buffalo ear fibroblast nucleus was fused into swamp buffalo oocyte cytoplasm. The blastocyst formation rate for nuclear transfer of freshly thawed cells was not different from those of growing cells, confluent or serum-starved cells. A total of 122 cloned blastocysts derived from cryopreserved fibroblasts were cryopreserved and thawed, 37 were survived, the cryosurvival rate was 30.3%. The survived blastocysts were transferred into 15 recipient buffalos. Five of the recipients established pregnancy, but four of them aborted on day 53, 59, 145 and 179 of gestation respectively. One cross-bred buffalo (Murrah × Swamp buffalo (2n = 49) received three embryos delivered a 40.5 kg female calf by natural delivery on day 320 of gestation. Up to now (13-month old), the cloned calf has been growing well with no abnormity observed. These results demonstrated that cryopreservation of inter-subspecies cloned embryos is feasible to produce buffalo offspring. PMID:19788521

  7. Production of human CD59-transgenic pigs by embryonic germ cell nuclear transfer

    SciTech Connect

    Ahn, Kwang Sung; Won, Ji Young; Park, Jin-Ki; Sorrell, Alice M.; Heo, Soon Young; Kang, Jee Hyun; Woo, Jae-Seok; Choi, Bong-Hwan; Chang, Won-Kyong; Shim, Hosup

    2010-10-01

    Research highlights: {yields} Human CD59 (hCD59) gene was introduced into porcine embryonic germ (EG) cells. {yields} hCD59-transgenic EG cells were resistant to hyperacute rejection in cytolytic assay. {yields} hCD59-transgenic pigs were produced by EG cell nuclear transfer. -- Abstract: This study was performed to produce transgenic pigs expressing the human complement regulatory protein CD59 (hCD59) using the nuclear transfer (NT) of embryonic germ (EG) cells, which are undifferentiated stem cells derived from primordial germ cells. Because EG cells can be cultured indefinitely in an undifferentiated state, they may provide an inexhaustible source of nuclear donor cells for NT to produce transgenic pigs. A total of 1980 NT embryos derived from hCD59-transgenic EG cells were transferred to ten recipients, resulting in the birth of fifteen piglets from three pregnancies. Among these offspring, ten were alive without overt health problems. Based on PCR analysis, all fifteen piglets were confirmed as hCD59 transgenic. The expression of the hCD59 transgene in the ten living piglets was verified by RT-PCR. Western analysis showed the expression of the hCD59 protein in four of the ten RT-PCR-positive piglets. These results demonstrate that hCD59-transgenic pigs could effectively be produced by EG cell NT and that such transgenic pigs may be used as organ donors in pig-to-human xenotransplantation.

  8. Reprogramming within hours following nuclear transfer into mouse but not human zygotes.

    PubMed

    Egli, Dieter; Chen, Alice E; Saphier, Genevieve; Ichida, Justin; Fitzgerald, Claire; Go, Kathryn J; Acevedo, Nicole; Patel, Jay; Baetscher, Manfred; Kearns, William G; Goland, Robin; Leibel, Rudolph L; Melton, Douglas A; Eggan, Kevin

    2011-01-01

    Fertilized mouse zygotes can reprogram somatic cells to a pluripotent state. Human zygotes might therefore be useful for producing patient-derived pluripotent stem cells. However, logistical, legal and social considerations have limited the availability of human eggs for research. Here we show that a significant number of normal fertilized eggs (zygotes) can be obtained for reprogramming studies. Using these zygotes, we found that when the zygotic genome was replaced with that of a somatic cell, development progressed normally throughout the cleavage stages, but then arrested before the morula stage. This arrest was associated with a failure to activate transcription in the transferred somatic genome. In contrast to human zygotes, mouse zygotes reprogrammed the somatic cell genome to a pluripotent state within hours after transfer. Our results suggest that there may be a previously unappreciated barrier to successful human nuclear transfer, and that future studies could focus on the requirements for genome activation. PMID:21971503

  9. PRESTO polarization transfer to quadrupolar nuclei: Implications for dynamic nuclear polarization

    DOE PAGESBeta

    Perras, Frederic A.; Kobayashi, Takeshi; Pruski, Marek

    2015-08-04

    In this study, we show both experimentally and numerically on a series of model systems that in experiments involving transfer of magnetization from 1H to the quadrupolar nuclei under magic-angle-spinning (MAS), the PRESTO technique consistently outperforms traditionally used cross polarization (CP), affording more quantitative intensities, improved lineshapes, better overall sensitivity, and straightforward optimization. This advantage derives from the fact that PRESTO circumvents the convoluted and uncooperative spin dynamics during the CP transfer under MAS, by replacing the spin-locking of quadrupolar nuclei with a single central transition selective 90° pulse and using a symmetry-based recoupling sequence in the 1H channel. Thismore » is important in the context of dynamic nuclear polarization (DNP) NMR of quadrupolar nuclei, where the efficient transfer of enhanced 1H polarization is desired to obtain the highest sensitivity.« less

  10. PRESTO polarization transfer to quadrupolar nuclei: Implications for dynamic nuclear polarization

    SciTech Connect

    Perras, Frederic A.; Kobayashi, Takeshi; Pruski, Marek

    2015-08-04

    In this study, we show both experimentally and numerically on a series of model systems that in experiments involving transfer of magnetization from 1H to the quadrupolar nuclei under magic-angle-spinning (MAS), the PRESTO technique consistently outperforms traditionally used cross polarization (CP), affording more quantitative intensities, improved lineshapes, better overall sensitivity, and straightforward optimization. This advantage derives from the fact that PRESTO circumvents the convoluted and uncooperative spin dynamics during the CP transfer under MAS, by replacing the spin-locking of quadrupolar nuclei with a single central transition selective 90° pulse and using a symmetry-based recoupling sequence in the 1H channel. This is important in the context of dynamic nuclear polarization (DNP) NMR of quadrupolar nuclei, where the efficient transfer of enhanced 1H polarization is desired to obtain the highest sensitivity.

  11. Nonideal rotations in nuclear magnetic resonance: Estimation of coherence transfer leakage

    SciTech Connect

    Jerschow, Alexej

    2000-07-15

    When spherical tensors are rotated by certain angles, coherence transfer selection rules may apply. For example, a {pi} rotation cleanly inverts the coherence order. A {pi}/2 rotation of a T{sub 0}{sup 1} tensor creates only T{sub {+-}}{sub 1}{sup 1} tensors. In this work estimations are given for the coherence transfer leakage under the action of rotations with small errors in the rotation angle or axis. Although the theory is stated with particular applications to NMR (nuclear magnetic resonance) in mind it is equally applicable wherever nonideal rotations of spherical tensors are considered (e.g., quantum computing and relaxation theory). In NMR it is useful for the estimation of coherence transfer leakage, especially in pulse sequences with many n{pi} pulses. The results are also applicable to spinors and half-integer representations of the rotation group. (c) 2000 American Institute of Physics.

  12. PRESTO polarization transfer to quadrupolar nuclei: implications for dynamic nuclear polarization.

    PubMed

    Perras, Frédéric A; Kobayashi, Takeshi; Pruski, Marek

    2015-09-21

    We show both experimentally and numerically on a series of model systems that in experiments involving transfer of magnetization from (1)H to the quadrupolar nuclei under magic-angle-spinning (MAS), the PRESTO technique consistently outperforms traditionally used cross polarization (CP), affording more quantitative intensities, improved lineshapes, better overall sensitivity, and straightforward optimization. This advantage derives from the fact that PRESTO circumvents the convoluted and uncooperative spin dynamics during the CP transfer under MAS, by replacing the spin-locking of quadrupolar nuclei with a single central transition selective 90° pulse and using a symmetry-based recoupling sequence in the (1)H channel. This is of particular importance in the context of dynamic nuclear polarization (DNP) NMR of quadrupolar nuclei, where the efficient transfer of enhanced (1)H polarization is desired to obtain the highest sensitivity. PMID:26266874

  13. Artificial intelligence and nuclear power. Report by the Technology Transfer Artificial Intelligence Task Team

    SciTech Connect

    Not Available

    1985-06-01

    The Artificial Intelligence Task Team was organized to review the status of Artificial Intelligence (AI) technology, identify guidelines for AI work, and to identify work required to allow the nuclear industry to realize maximum benefit from this technology. The state of the nuclear industry was analyzed to determine where the application of AI technology could be of greatest benefit. Guidelines and criteria were established to focus on those particular problem areas where AI could provide the highest possible payoff to the industry. Information was collected from government, academic, and private organizations. Very little AI work is now being done to specifically support the nuclear industry. The AI Task Team determined that the establishment of a Strategic Automation Initiative (SAI) and the expansion of the DOE Technology Transfer program would ensure that AI technology could be used to develop software for the nuclear industry that would have substantial financial payoff to the industry. The SAI includes both long and short term phases. The short-term phase includes projects which would demonstrate that AI can be applied to the nuclear industry safely, and with substantial financial benefit. The long term phase includes projects which would develop AI technologies with specific applicability to the nuclear industry that would not be developed by people working in any other industry.

  14. Rabbit embryonic stem cell lines derived from fertilized, parthenogenetic or somatic cell nuclear transfer embryos

    SciTech Connect

    Fang, Zhen F.; Gai, Hui; Huang, You Z.; Li, Shan G.; Chen, Xue J.; Shi, Jian J.; Wu, Li; Liu, Ailian; Xu, Ping; Sheng, Hui Z. . E-mail: hzsheng2003@yahoo.com

    2006-11-01

    Embryonic stem cells were isolated from rabbit blastocysts derived from fertilization (conventional rbES cells), parthenogenesis (pES cells) and nuclear transfer (ntES cells), and propagated in a serum-free culture system. Rabbit ES (rbES) cells proliferated for a prolonged time in an undifferentiated state and maintained a normal karyotype. These cells grew in a monolayer with a high nuclear/cytoplasm ratio and contained a high level of alkaline phosphate activity. In addition, rbES cells expressed the pluripotent marker Oct-4, as well as EBAF2, FGF4, TDGF1, but not antigens recognized by antibodies against SSEA-1, SSEA-3, SSEA-4, TRA-1-10 and TRA-1-81. All 3 types of ES cells formed embryoid bodies and generated teratoma that contained tissue types of all three germ layers. rbES cells exhibited a high cloning efficiency, were genetically modified readily and were used as nuclear donors to generate a viable rabbit through somatic cell nuclear transfer. In combination with genetic engineering, the ES cell technology should facilitate the creation of new rabbit lines.

  15. Widespread interspecies homologous recombination reveals reticulate evolution within the genus Streptomyces.

    PubMed

    Cheng, Kun; Rong, Xiaoying; Huang, Ying

    2016-09-01

    Homologous recombination is increasingly being recognized as a driving force in microbial evolution. However, recombination in streptomycetes, a rich source of diverse secondary metabolites, particularly among different species, remains minimally investigated. In this study, the largest sample of Streptomyces species to date, consisting of 142 type strains spanning the genus, with available sequences of 16S rRNA, atpD, gyrB, recA, rpoB and trpB genes, were collected and subjected to a comprehensive population genetic analysis to generate an overall estimate of the level of Streptomyces interspecies genetic exchange and its effect on the evolution of this genus. The results indicate frequent homologous recombination among Streptomyces species, which occurred three times more frequently and was nearly 14 times more important than point mutation in nucleotide sequence divergence (ρ/θw=3.10, r/m=13.74). As a result, a facilitating effect on the evolutionary process and confusion in phylogenetic relationships were observed, as well as a number of specific transfer events of the six gene fragments. A resultant phylogenetic network depicted extensive horizontal genetic exchange which decays clonality in streptomycetes. Moreover, seven evolutionary lineage groups were identified in the present sample in the Structure analysis, generally consistent with morphological and physiological data, and the contribution of recombination was detected to be varied among them. Our analyses demonstrated a reticulate evolution within Streptomyces due to the high level of interspecies gene exchange, which greatly challenges the traditional tree-shaped phylogeny in this genus and may advance our evolutionary understanding of a genuine Streptomyces species. PMID:27329941

  16. Coherent transfer of nuclear spin polarization in field-cycling NMR experiments

    SciTech Connect

    Pravdivtsev, Andrey N.; Yurkovskaya, Alexandra V.; Ivanov, Konstantin L.; Vieth, Hans-Martin

    2013-12-28

    Coherent polarization transfer effects in a coupled spin network have been studied over a wide field range. The transfer mechanism is based on exciting zero-quantum coherences between the nuclear spin states by means of non-adiabatic field jump from high to low magnetic field. Subsequent evolution of these coherences enables conversion of spin order in the system, which is monitored after field jump back to high field. Such processes are most efficient when the spin system passes through an avoided level crossing during the field variation. The polarization transfer effects have been demonstrated for N-acetyl histidine, which has five scalar coupled protons; the initial spin order has been prepared by applying RF-pulses at high magnetic field. The observed oscillatory transfer kinetics is taken as a clear indication of a coherent mechanism; level crossing effects have also been demonstrated. The experimental data are in very good agreement with the theoretical model of coherent polarization transfer. The method suggested is also valid for other types of initial polarization in the spin system, most notably, for spin hyperpolarization.

  17. Technological requirements of nuclear electric propulsion systems for fast Earth-Mars transfers

    NASA Astrophysics Data System (ADS)

    Bérend, N.; Epenoy, R.; Cliquet, E.; Laurent-Varin, J.; Avril, S.

    2013-03-01

    Recent advances in electric propulsion technologies such as magnetoplasma rockets gave a new momentum to the study of nuclear electric propulsion concepts for Mars missions. Some recent works have been focused on very short Earth-to-Mars transfers of about 40 days with high-power, variable specific impulse propulsion systems [1]. While the interest of nuclear electric propulsion appears clearly with regard to the payload mass ratio (due to a high level of specific impulse), its interest with regard to the transfer time is more complex to define, as it depends on many design parameters. In this paper, a general analysis of the capability of nuclear electric propulsion systems considering both criteria (the payload mass ratio and the transfer time) is performed, and the technological requirements for fast Earth-Mars transfers are studied. This analysis has been performed in two steps. First, complete trajectory optimizations have been performed by CNES-DCT in order to obtain the propulsion requirements of the mission for different technological hypotheses regarding the engine technology (specific impulse levels and the throttling capability) and different mission requirements. The methodology used for designing fuel-optimal heliocentric trajectories, based on the Pontryagin's Maximum Principle will be presented. Trajectories have been computed for various power levels combined with either variable or fixed Isp. The second step consisted in evaluating a simpler method that could easily link the main mission requirements (the transfer time and the payload fraction) to the main technological requirements (the specific mass of the power generation system and the structure mass ratio of the whole vehicle, excluding the power generation system). Indeed, for power-limited systems, propulsion requirements can be characterized through the "trajectory characteristic" parameter, defined as the integral over time of the squared thrust acceleration. Technological requirements for

  18. Production of Cloned Korean Native Pig by Somatic Cell Nuclear Transfer.

    PubMed

    Hwang, In-Sul; Kwon, Dae-Jin; Oh, Keun Bong; Ock, Sun-A; Chung, Hak-Jae; Cho, In-Cheol; Lee, Jeong-Woong; Im, Gi-Sun; Hwang, Seongsoo

    2015-06-01

    The Korean native pig (KNP) have been considered as animal models for animal biotechnology research because of their relatively small body size and their presumably highly inbred status due to the closed breeding program. However, little is reported about the use of KNP for animal biotechnology researches. This study was performed to establish the somatic cell nuclear transfer (SCNT) protocol for the production of swine leukocyte antigens (SLA) homotype-defined SCNT KNP. The ear fibroblast cells originated from KNP were cultured and used as donor cell. After thawing, the donor cells were cultured for 1 hour with 15 μM roscovitine prior to the nuclear transfer. The numbers of reconstructed and parthenogenetic embryos transferred were 98 ± 35.2 and 145 ± 11.2, respectively. The pregnancy and delivery rate were 3/5 (60%) and 2/5 (40%). One healthy SLA homotype-defined SCNT KNP was successfully generated. The recipient-based individual cloning efficiency ranged from 0.65 to 1.08%. Taken together, it can be postulated that the methodological establishment of the production of SLA homotype-defined cloned KNP can be applied to the generation of transgenic cloned KNP as model animals for human disease and xenotransplantation researches. PMID:27004264

  19. Establishment of an efficient somatic cell nuclear transfer system for production of transgenic pigs.

    PubMed

    Vajta, G; Callesen, H

    2012-04-15

    Handmade cloning (HMC) is now an established procedure used in several species for somatic cell nuclear transfer, but only applied in two related laboratories for pigs. The aim of this review is to facilitate widespread application by summarizing the process of establishment and explaining the background of the incorporated special approaches. Optimized steps of traditional cloning in pigs (in vitro maturation, activation, embryo culture) were merged with those of the micromanipulation-free HMC that has been modified according to the specific needs of sensitive porcine oocytes (partial zona digestion before enucleation, two-step zona-free fusion with the somatic cell; initiation of activation with the second fusion). The zona-free approach required embryo culture to the blastocyst stage before surgical transfer of embryos to the uterine horns of recipient sows in the proper phase of an unstimulated cycle. Eventually a competitive, inexpensive and reliable alternative to traditional porcine nuclear transfer cloning techniques evolved that is also suitable to produce transgenic offspring containing various genetic modifications to establish models for several human diseases with genetic background. Further improvements and involvement of additional techniques to increase the overall efficiency and facilitate practical applications are expected in the foreseeable future. PMID:22284219

  20. Production of Cloned Korean Native Pig by Somatic Cell Nuclear Transfer

    PubMed Central

    Hwang, In-Sul; Kwon, Dae-Jin; Oh, Keun Bong; Ock, Sun-A; Chung, Hak-Jae; Cho, In-Cheol; Lee, Jeong-Woong; Im, Gi-Sun; Hwang, Seongsoo

    2015-01-01

    The Korean native pig (KNP) have been considered as animal models for animal biotechnology research because of their relatively small body size and their presumably highly inbred status due to the closed breeding program. However, little is reported about the use of KNP for animal biotechnology researches. This study was performed to establish the somatic cell nuclear transfer (SCNT) protocol for the production of swine leukocyte antigens (SLA) homotype-defined SCNT KNP. The ear fibroblast cells originated from KNP were cultured and used as donor cell. After thawing, the donor cells were cultured for 1 hour with 15 μM roscovitine prior to the nuclear transfer. The numbers of reconstructed and parthenogenetic embryos transferred were 98 ± 35.2 and 145 ± 11.2, respectively. The pregnancy and delivery rate were 3/5 (60%) and 2/5 (40%). One healthy SLA homotype-defined SCNT KNP was successfully generated. The recipient-based individual cloning efficiency ranged from 0.65 to 1.08%. Taken together, it can be postulated that the methodological establishment of the production of SLA homotype-defined cloned KNP can be applied to the generation of transgenic cloned KNP as model animals for human disease and xenotransplantation researches. PMID:27004264

  1. Identification of Nuclear Effects in Neutrino-Carbon Interactions at Low Three-Momentum Transfer.

    PubMed

    Rodrigues, P A; Demgen, J; Miltenberger, E; Aliaga, L; Altinok, O; Bellantoni, L; Bercellie, A; Betancourt, M; Bodek, A; Bravar, A; Budd, H; Cai, T; Carneiro, M F; Chvojka, J; Devan, J; Dytman, S A; Díaz, G A; Eberly, B; Elkins, M; Felix, J; Fields, L; Fine, R; Gago, A M; Galindo, R; Gallagher, H; Ghosh, A; Golan, T; Gran, R; Harris, D A; Higuera, A; Hurtado, K; Kiveni, M; Kleykamp, J; Kordosky, M; Le, T; Leistico, J R; Lovlein, A; Maher, E; Manly, S; Mann, W A; Marshall, C M; Martinez Caicedo, D A; McFarland, K S; McGivern, C L; McGowan, A M; Messerly, B; Miller, J; Mislivec, A; Morfín, J G; Mousseau, J; Muhlbeier, T; Naples, D; Nelson, J K; Norrick, A; Nuruzzaman; Osta, J; Paolone, V; Patrick, C E; Perdue, G N; Ramirez, M A; Ransome, R D; Ray, H; Ren, L; Rimal, D; Ruterbories, D; Schellman, H; Schmitz, D W; Solano Salinas, C J; Tagg, N; Tice, B G; Valencia, E; Walton, T; Wolcott, J; Wospakrik, M; Zavala, G; Zhang, D

    2016-02-19

    Two different nuclear-medium effects are isolated using a low three-momentum transfer subsample of neutrino-carbon scattering data from the MINERvA neutrino experiment. The observed hadronic energy in charged-current ν_{μ} interactions is combined with muon kinematics to permit separation of the quasielastic and Δ(1232) resonance processes. First, we observe a small cross section at very low energy transfer that matches the expected screening effect of long-range nucleon correlations. Second, additions to the event rate in the kinematic region between the quasielastic and Δ resonance processes are needed to describe the data. The data in this kinematic region also have an enhanced population of multiproton final states. Contributions predicted for scattering from a nucleon pair have both properties; the model tested in this analysis is a significant improvement but does not fully describe the data. We present the results as a double-differential cross section to enable further investigation of nuclear models. Improved description of the effects of the nuclear environment are required by current and future neutrino oscillation experiments. PMID:26943528

  2. Genetic Drift Can Compromise Mitochondrial Replacement by Nuclear Transfer in Human Oocytes.

    PubMed

    Yamada, Mitsutoshi; Emmanuele, Valentina; Sanchez-Quintero, Maria J; Sun, Bruce; Lallos, Gregory; Paull, Daniel; Zimmer, Matthew; Pagett, Shardonay; Prosser, Robert W; Sauer, Mark V; Hirano, Michio; Egli, Dieter

    2016-06-01

    Replacement of mitochondria through nuclear transfer between oocytes of two different women has emerged recently as a strategy for preventing inheritance of mtDNA diseases. Although experiments in human oocytes have shown effective replacement, the consequences of small amounts of mtDNA carryover have not been studied sufficiently. Using human mitochondrial replacement stem cell lines, we show that, even though the low levels of heteroplasmy introduced into human oocytes by mitochondrial carryover during nuclear transfer often vanish, they can sometimes instead result in mtDNA genotypic drift and reversion to the original genotype. Comparison of cells with identical oocyte-derived nuclear DNA but different mtDNA shows that either mtDNA genotype is compatible with the nucleus and that drift is independent of mitochondrial function. Thus, although functional replacement of the mitochondrial genome is possible, even low levels of heteroplasmy can affect the stability of the mtDNA genotype and compromise the efficacy of mitochondrial replacement. PMID:27212703

  3. Identification of Nuclear Effects in Neutrino-Carbon Interactions at Low Three-Momentum Transfer

    NASA Astrophysics Data System (ADS)

    Rodrigues, P. A.; Demgen, J.; Miltenberger, E.; Aliaga, L.; Altinok, O.; Bellantoni, L.; Bercellie, A.; Betancourt, M.; Bodek, A.; Bravar, A.; Budd, H.; Cai, T.; Carneiro, M. F.; Chvojka, J.; Devan, J.; Dytman, S. A.; Díaz, G. A.; Eberly, B.; Elkins, M.; Felix, J.; Fields, L.; Fine, R.; Gago, A. M.; Galindo, R.; Gallagher, H.; Ghosh, A.; Golan, T.; Gran, R.; Harris, D. A.; Higuera, A.; Hurtado, K.; Kiveni, M.; Kleykamp, J.; Kordosky, M.; Le, T.; Leistico, J. R.; Lovlein, A.; Maher, E.; Manly, S.; Mann, W. A.; Marshall, C. M.; Martinez Caicedo, D. A.; McFarland, K. S.; McGivern, C. L.; McGowan, A. M.; Messerly, B.; Miller, J.; Mislivec, A.; Morfín, J. G.; Mousseau, J.; Muhlbeier, T.; Naples, D.; Nelson, J. K.; Norrick, A.; Nuruzzaman; Osta, J.; Paolone, V.; Patrick, C. E.; Perdue, G. N.; Ramirez, M. A.; Ransome, R. D.; Ray, H.; Ren, L.; Rimal, D.; Ruterbories, D.; Schellman, H.; Schmitz, D. W.; Solano Salinas, C. J.; Tagg, N.; Tice, B. G.; Valencia, E.; Walton, T.; Wolcott, J.; Wospakrik, M.; Zavala, G.; Zhang, D.; Minerva Collaboration

    2016-02-01

    Two different nuclear-medium effects are isolated using a low three-momentum transfer subsample of neutrino-carbon scattering data from the MINERvA neutrino experiment. The observed hadronic energy in charged-current νμ interactions is combined with muon kinematics to permit separation of the quasielastic and Δ (1232 ) resonance processes. First, we observe a small cross section at very low energy transfer that matches the expected screening effect of long-range nucleon correlations. Second, additions to the event rate in the kinematic region between the quasielastic and Δ resonance processes are needed to describe the data. The data in this kinematic region also have an enhanced population of multiproton final states. Contributions predicted for scattering from a nucleon pair have both properties; the model tested in this analysis is a significant improvement but does not fully describe the data. We present the results as a double-differential cross section to enable further investigation of nuclear models. Improved description of the effects of the nuclear environment are required by current and future neutrino oscillation experiments.

  4. Identification of nuclear effects in neutrino-carbon interactions at low three-momentum transfer

    DOE PAGESBeta

    Rodrigues, P. A.

    2016-02-17

    Two different nuclear-medium effects are isolated using a low three-momentum transfer subsample of neutrino-carbon scattering data from the MINERvA neutrino experiment. The observed hadronic energy in charged-current νμ interactions is combined with muon kinematics to permit separation of the quasielastic and Δ(1232) resonance processes. First, we observe a small cross section at very low energy transfer that matches the expected screening effect of long-range nucleon correlations. Second, additions to the event rate in the kinematic region between the quasielastic and Δ resonance processes are needed to describe the data. The data in this kinematic region also have an enhanced populationmore » of multiproton final states. Contributions predicted for scattering from a nucleon pair have both properties; the model tested in this analysis is a significant improvement but does not fully describe the data. We present the results as a double-differential cross section to enable further investigation of nuclear models. Furthermore, improved description of the effects of the nuclear environment are required by current and future neutrino oscillation experiments.« less

  5. Coupled electron-nuclear dynamics: Charge migration and charge transfer initiated near a conical intersection

    NASA Astrophysics Data System (ADS)

    Mendive-Tapia, David; Vacher, Morgane; Bearpark, Michael J.; Robb, Michael A.

    2013-07-01

    Coupled electron-nuclear dynamics, implemented using the Ehrenfest method, has been used to study charge migration with fixed nuclei, together with charge transfer when nuclei are allowed to move. Simulations were initiated at reference geometries of neutral benzene and 2-phenylethylamine (PEA), and at geometries close to potential energy surface crossings in the cations. Cationic eigenstates, and the so-called sudden approximation, involving removal of an electron from a correlated ground-state wavefunction for the neutral species, were used as initial conditions. Charge migration without coupled nuclear motion could be observed if the Ehrenfest simulation, using the sudden approximation, was started near a conical intersection where the states were both strongly coupled and quasi-degenerate. Further, the main features associated with charge migration were still recognizable when the nuclear motion was allowed to couple. In the benzene radical cation, starting from the reference neutral geometry with the sudden approximation, one could observe sub-femtosecond charge migration with a small amplitude, which results from weak interaction with higher electronic states. However, we were able to engineer large amplitude charge migration, with a period between 10 and 100 fs, corresponding to oscillation of the electronic structure between the quinoid and anti-quinoid cationic electronic configurations, by distorting the geometry along the derivative coupling vector from the D6h Jahn-Teller crossing to lower symmetry where the states are not degenerate. When the nuclear motion becomes coupled, the period changes only slightly. In PEA, in an Ehrenfest trajectory starting from the D2 eigenstate and reference geometry, a partial charge transfer occurs after about 12 fs near the first crossing between D1, D2 (N+-Phenyl, N-Phenyl+). If the Ehrenfest propagation is started near this point, using the sudden approximation without coupled nuclear motion, one observes an

  6. Coupled electron-nuclear dynamics: charge migration and charge transfer initiated near a conical intersection.

    PubMed

    Mendive-Tapia, David; Vacher, Morgane; Bearpark, Michael J; Robb, Michael A

    2013-07-28

    Coupled electron-nuclear dynamics, implemented using the Ehrenfest method, has been used to study charge migration with fixed nuclei, together with charge transfer when nuclei are allowed to move. Simulations were initiated at reference geometries of neutral benzene and 2-phenylethylamine (PEA), and at geometries close to potential energy surface crossings in the cations. Cationic eigenstates, and the so-called sudden approximation, involving removal of an electron from a correlated ground-state wavefunction for the neutral species, were used as initial conditions. Charge migration without coupled nuclear motion could be observed if the Ehrenfest simulation, using the sudden approximation, was started near a conical intersection where the states were both strongly coupled and quasi-degenerate. Further, the main features associated with charge migration were still recognizable when the nuclear motion was allowed to couple. In the benzene radical cation, starting from the reference neutral geometry with the sudden approximation, one could observe sub-femtosecond charge migration with a small amplitude, which results from weak interaction with higher electronic states. However, we were able to engineer large amplitude charge migration, with a period between 10 and 100 fs, corresponding to oscillation of the electronic structure between the quinoid and anti-quinoid cationic electronic configurations, by distorting the geometry along the derivative coupling vector from the D6h Jahn-Teller crossing to lower symmetry where the states are not degenerate. When the nuclear motion becomes coupled, the period changes only slightly. In PEA, in an Ehrenfest trajectory starting from the D2 eigenstate and reference geometry, a partial charge transfer occurs after about 12 fs near the first crossing between D1, D2 (N(+)-Phenyl, N-Phenyl(+)). If the Ehrenfest propagation is started near this point, using the sudden approximation without coupled nuclear motion, one observes an

  7. Coupled electron-nuclear dynamics: Charge migration and charge transfer initiated near a conical intersection

    SciTech Connect

    Mendive-Tapia, David; Vacher, Morgane; Bearpark, Michael J.; Robb, Michael A.

    2013-07-28

    Coupled electron-nuclear dynamics, implemented using the Ehrenfest method, has been used to study charge migration with fixed nuclei, together with charge transfer when nuclei are allowed to move. Simulations were initiated at reference geometries of neutral benzene and 2-phenylethylamine (PEA), and at geometries close to potential energy surface crossings in the cations. Cationic eigenstates, and the so-called sudden approximation, involving removal of an electron from a correlated ground-state wavefunction for the neutral species, were used as initial conditions. Charge migration without coupled nuclear motion could be observed if the Ehrenfest simulation, using the sudden approximation, was started near a conical intersection where the states were both strongly coupled and quasi-degenerate. Further, the main features associated with charge migration were still recognizable when the nuclear motion was allowed to couple. In the benzene radical cation, starting from the reference neutral geometry with the sudden approximation, one could observe sub-femtosecond charge migration with a small amplitude, which results from weak interaction with higher electronic states. However, we were able to engineer large amplitude charge migration, with a period between 10 and 100 fs, corresponding to oscillation of the electronic structure between the quinoid and anti-quinoid cationic electronic configurations, by distorting the geometry along the derivative coupling vector from the D{sub 6h} Jahn-Teller crossing to lower symmetry where the states are not degenerate. When the nuclear motion becomes coupled, the period changes only slightly. In PEA, in an Ehrenfest trajectory starting from the D{sub 2} eigenstate and reference geometry, a partial charge transfer occurs after about 12 fs near the first crossing between D{sub 1}, D{sub 2} (N{sup +}-Phenyl, N-Phenyl{sup +}). If the Ehrenfest propagation is started near this point, using the sudden approximation without coupled

  8. Human-mouse interspecies collagen I heterotrimer is functional during embryonic development of Mov13 mutant mouse embryos.

    PubMed Central

    Wu, H; Bateman, J F; Schnieke, A; Sharpe, A; Barker, D; Mascara, T; Eyre, D; Bruns, R; Krimpenfort, P; Berns, A

    1990-01-01

    To investigate whether the human pro alpha 1(I) collagen chain could form an in vivo functional interspecies heterotrimer with the mouse pro alpha 2(I) collagen chain, we introduced the human COL1A1 gene into Mov13 mice which have a functional deletion of the endogenous COL1A1 gene. Transgenic mouse strains (HucI and HucII) carrying the human COL1A1 gene were first generated by microinjecting the COL1A1 gene into wild-type mouse embryos. Genetic evidence indicated that the transgene in the HucI strain was closely linked to the endogenous mouse COL1A1 gene and was X linked in the HucII transgenic strain. Northern (RNA) blot and S1 protection analyses showed that the transgene was expressed in the appropriate tissue-specific manner and as efficiently as the endogenous COL1A1 gene. HucII mice were crossed with Mov13 mice to transfer the human transgene into the mutant strain. Whereas homozygous Mov13 embryos die between days 13 and 14 of gestation, the presence of the transgene permitted apparently normal development of the mutant embryos to birth. This indicated that the mouse-human interspecies collagen I heterotrimer was functional in the animal. The rescue was, however, only partial, as all homozygotes died within 36 h after delivery, with signs of internal bleeding. This could have been due to a functional defect in the interspecies hybrid collagen. Extensive analysis failed to reveal any biochemical or morphological abnormalities of the collagen I molecules in Mov13-HucII embryos.(ABSTRACT TRUNCATED AT 250 WORDS) Images PMID:1690840

  9. Cats cloned from fetal and adult somatic cells by nuclear transfer.

    PubMed

    Yin, X J; Lee, H S; Lee, Y H; Seo, Y I; Jeon, S J; Choi, E G; Cho, S J; Cho, S G; Min, W; Kang, S K; Hwang, W S; Kong, I K

    2005-02-01

    This work was undertaken in order to study the developmental competence of nuclear transfer (NT) into cat embryos using fetal fibroblast and adult skin fibroblast cells as donor nuclei. Oocytes were recovered by mincing the ovaries in Hepes-buffered TCM199 and selecting the cumulus oocyte complexes (COCs) with compact cumulus cell mass and dark color. Homogenous ooplasm was cultured for maturation in TCM199+10% fetal bovine serum (FBS) for 12 h and used as a source of recipient cytoplast for exogenous somatic nuclei. In experiment 1, we evaluated the effect of donor cell type on the reconstruction and development of cloned embryos. Fusion, first cleavage and blastocyst developmental rate were not different between fetal fibroblasts and adult skin cells (71.2 vs 66.8; 71.0 vs 57.6; 4.0 vs 6.1% respectively; P < 0.05). In experiment 2, cloned embryos were surgically transferred into the oviducts of recipient queens. One of the seven recipient queens was delivered naturally of 2 healthy cloned cats and 1 stillborn from fetal fibroblast cells of male origin 65 days after embryo transfer. One of three recipient queens was delivered naturally of 1 healthy cloned cat from adult skin cells of female origin 65 days after embryo transfer. The cloned cats showed genotypes identical to the donor cell lines, indicating that adult somatic cells can be used for feline cloning. PMID:15695619

  10. Cytoplasmic Inheritance of Transplantation Antigens In Animals Produced by Nuclear Transfer

    PubMed Central

    Hanekamp, John S.; Okumi, Masayoshi; Tena, Aseda; Arn, Scott; Yamada, Kazuhiko; Sachs, David H.

    2010-01-01

    Background Nuclear transfer has been utilized as a means of selectively modifying the mammalian genome. One possible consequence of this technology is that the oocytes used in nuclear transfer may provide additional antigens via cytoplasmic inheritance of maternally derived, mitochondrial DNA. These studies examine the potential consequences of such inheritance in a large animal transplantation model. Methods Renal transplants were performed between MHC-identical animals differing only in the source of their maternally derived cytoplasmic DNA, using a protocol which uniformly leads to tolerance within standard MHC-inbred lines. In an attempt to correlate transplant results with a putative marker for disparities in cytoplasmically inherited minor histocompatibility antigens, we examined one hypervariable region of mitochondrial DNA (mtDNA), designated HV1. Results The mtDNA sequence of the HV1 region was found to be invariant among MGH miniature swine of different haplotypes, despite twenty years of selective breeding of the sublines of this colony. In contrast, swine derived by nuclear transfer into outbred oocytes differed in the HV1 region sequence from each other and from MGH swine. Renal transplants from standard, inbred MGH swine to their MHC-identical knockout counterparts derived from outbred oocytes were rejected within two weeks, while transplants in the reverse direction were accepted for over 30 days. Conclusions The HV1 sequence of mtDNA may serve as a marker for the level of diversity of mtDNA. These transplant data are consistent with the existence of mtDNA-encoded mitochondrial minor antigens with a similar level of diversity that can influence the outcome of renal transplantation. PMID:19584677

  11. Nuclear transfer of porcine embryos using cryopreserved delipated blastomeres as donor nuclei.

    PubMed

    Nagashima, H; Ashman, R J; Nottle, M B

    1997-11-01

    Nuclear transfer protocol for the pig using cryopreserved delipated four- to eight-cell and morula stage embryos as nucleus donors was developed. Donor embryos, which had been delipated by micromanipulation following centrifugation for polarizing cytoplasmic lipid droplets, were cryopreserved with 1.5 M 1,2-propanediol and 0.1 M sucrose. Recipient cytoplasts were prepared from ovulated oocytes. Activation of oocytes could be induced more efficiently when electric stimulation was given 53 hr after the hCG injection or later (66-83%), compared with 52 hr or earlier (11-16%, P < 0.05), suggesting that aging after ovulation may be required for in vivo matured porcine oocytes to be activated by electric stimuli. Membrane fusion rates between donor blastomeres and enucleated oocytes were 88% (127/144) and 97% (56/58, P > 0.05) for the four- to eight-cell and morula stage embryos, respectively. In vitro developmental rates to the two-cell (53/100 vs. 35/65), four-cell (34/100 vs. 26/65), and morula stage (17/100 vs. 18/65) were the same between the nuclear transfer embryos with four- to eight-cell and morula nuclei. However, more embryos reconstituted with morula nuclei developed to blastocysts (15% vs. 6%, P < 0.05). These data demonstrated that blastomeres of cryopreserved, delipated porcine embryos can be used as donor nuclei for nuclear transfer. Frozen-thawed, delipated blastomeres can be efficiently isolated and fused, and therefore provide a useful source of donor nuclei. PMID:9322245

  12. Somatic cell nuclear transfer-derived embryonic stem cell lines in humans: pros and cons.

    PubMed

    Langerova, Alena; Fulka, Helena; Fulka, Josef

    2013-12-01

    The recent paper, published by Mitalipov's group in Cell (Tachibana et al., 2013 ), reporting the production of human somatic cell nuclear transfer (SCNT) embryonic stem cells (ESCs), opens again the debate if, in the era of induced pluripotent stem cells (iPSCs), the production of these cells is indeed necessary and, if so, whether they are different from ESCs produced from spare embryos and iPSCs. It is our opinion that these questions are very difficult to answer because it is still unclear whether and how normal ESCs differ from iPSCs. PMID:24180743

  13. Nuclear propulsion systems for orbit transfer based on the particle bed reactor

    SciTech Connect

    Powell, J.R.; Ludewig, H.; Horn, F.L.; Araj, K.; Benenati, R.; Lazareth, O.; Slovik, G.; Solon, M.; Tappe, W.; Belisle, J.

    1987-01-01

    The technology of nuclear direct propulsion orbit transfer systems based on the Particle Bed Reactor (PBR) is described. A 200 megawatt illustrative design is presented for LEO to GEO and other high ..delta..V missions. The PBR-NOTV can be used in a one-way mode with the shuttle or an expendable launch vehicle, e.g., the Titan 34D7, or as a two-way reusable space tug. In the one-way mode, payload capacity is almost three times greater than that of chemical OTV's. PBR technology status is described and development needs outlined.

  14. Development of porcine tetraploid somatic cell nuclear transfer embryos is influenced by oocyte nuclei.

    PubMed

    Fu, Bo; Liu, Di; Ma, Hong; Guo, Zhen-Hua; Wang, Liang; Li, Zhong-Qiu; Peng, Fu-Gang; Bai, Jing

    2016-02-01

    Cloning efficiency in mammalian systems remains low because reprogramming of donor cells is frequently incomplete. Nuclear factors in the oocyte are removed by enucleation, and this removal may adversely affect reprogramming efficiency. Here, we investigated the role of porcine oocyte nuclear factors during reprogramming. We introduced somatic cell nuclei into intact MII oocytes to establish tetraploid somatic cell nuclear transfer (SCNT) embryos containing both somatic nuclei and oocyte nuclei. We then examined the influence of the oocyte nucleus on tetraploid SCNT embryo development by assessing characteristics including pronucleus formation, cleavage rate, and blastocyst formation. Overall, tetraploid SCNT embryos have a higher developmental competence than do standard diploid SCNT embryos. Therefore, we have established an embryonic model in which a fetal fibroblast nucleus and an oocyte metaphase II plate coexist. Tetraploid SCNT represents a new research platform that is potentially useful for examining interactions between donor nuclei and oocyte nuclei. This platform should facilitate further understanding of the roles played by nuclear factors during reprogramming. PMID:26503330

  15. Nuclear event time histories and computed site transfer functions for locations in the Los Angeles region

    USGS Publications Warehouse

    Rogers, A.M.; Covington, P.A.; Park, R.B.; Borcherdt, R.D.; Perkins, D.M.

    1980-01-01

    This report presents a collection of Nevada Test Site (NTS) nuclear explosion recordings obtained at sites in the greater Los Angeles, Calif., region. The report includes ground velocity time histories, as well as, derived site transfer functions. These data have been collected as part of a study to evaluate the validity of using low-level ground motions to predict the frequency-dependent response of a site during an earthquake. For this study 19 nuclear events were recorded at 98 separate locations. Some of these sites have recorded more than one of the nuclear explosions, and, consequently, there are a total of 159, three-component station records. The location of all the recording sites are shown in figures 1–5, the station coordinates and abbreviations are given in table 1. The station addresses are listed in table 2, and the nuclear explosions that were recorded are listed in table 3. The recording sites were chosen on the basis of three criteria: (1) that the underlying geological conditions were representative of conditions over significant areas of the region, (2) that the site was the location of a strong-motion recording of the 1971 San Fernando earthquake, or (3) that more complete geographical coverage was required in that location.

  16. Comparative Analysis of Nuclear Transfer Embryo-Derived Mouse Embryonic Stem Cells. Part I: Cellular Characterization

    PubMed Central

    Kobolak, Julianna; Mamo, Solomon; Rungsiwiwut, Ruttachuk; Ujhelly, Olga; Csonka, Erika; Hadlaczky, Gyula

    2012-01-01

    Abstract Embryonic stem cells derived from nuclear transfer embryos (ntESCs) are particularly valuable for regenerative medicine, as they are a patient-specific and histocompatible cell source for the treatment of varying diseases. However, currently, little is known about their cellular and molecular profile. In the present study, in a mouse model different donor cell-derived ntESCs from various genetic backgrounds were compared with reference ESCs and analyzed comprehensively at the cellular level. A number of pluripotency marker genes were compared by flow cytometry and immunocytochemistry analysis. Significant differences at the protein level were observed for POU5F1, SOX2, FGF4, NANOG, and SSEA-1. However, such differences had no effect on in vitro cell differentiation and cell fate: derivatives of the three germ layers were detected in all ntESC lines. The neural and cardiac in vitro differentiation revealed minor differences between the cell lines, both at the mRNA and protein level. Karyotype analyses and cell growth studies did not reveal any significant variations. Despite some differences observed, the present study revealed that ntESC lines had similar differentiation competences compared to other ESCs. The results indicate that the observed differences may be related to the genotype rather than to the nuclear transfer technology. PMID:22204592

  17. Targeted disruption of Ataxia-telangiectasia mutated gene in miniature pigs by somatic cell nuclear transfer

    SciTech Connect

    Kim, Young June; Ahn, Kwang Sung; Kim, Minjeong; Kim, Min Ju; Park, Sang-Min; Ryu, Junghyun; Ahn, Jin Seop; Heo, Soon Young; Kang, Jee Hyun; Choi, You Jung; Choi, Seong-Jun; Shim, Hosup

    2014-10-03

    Highlights: • ATM gene-targeted pigs were produced by somatic cell nuclear transfer. • A novel large animal model for ataxia telangiectasia was developed. • The new model may provide an alternative to the mouse model. - Abstract: Ataxia telangiectasia (A-T) is a recessive autosomal disorder associated with pleiotropic phenotypes, including progressive cerebellar degeneration, gonad atrophy, and growth retardation. Even though A-T is known to be caused by the mutations in the Ataxia telangiectasia mutated (ATM) gene, the correlation between abnormal cellular physiology caused by ATM mutations and the multiple symptoms of A-T disease has not been clearly determined. None of the existing ATM mouse models properly reflects the extent to which neurological degeneration occurs in human. In an attempt to provide a large animal model for A-T, we produced gene-targeted pigs with mutations in the ATM gene by somatic cell nuclear transfer. The disrupted allele in the ATM gene of cloned piglets was confirmed via PCR and Southern blot analysis. The ATM gene-targeted pigs generated in the present study may provide an alternative to the current mouse model for the study of mechanisms underlying A-T disorder and for the development of new therapies.

  18. Somatic cell nuclear transfer: Infinite reproduction of a unique diploid genome

    SciTech Connect

    Kishigami, Satoshi Wakayama, Sayaka; Hosoi, Yoshihiko; Iritani, Akira; Wakayama, Teruhiko

    2008-06-10

    In mammals, a diploid genome of an individual following fertilization of an egg and a spermatozoon is unique and irreproducible. This implies that the generated unique diploid genome is doomed with the individual ending. Even as cultured cells from the individual, they cannot normally proliferate in perpetuity because of the 'Hayflick limit'. However, Dolly, the sheep cloned from an adult mammary gland cell, changes this scenario. Somatic cell nuclear transfer (SCNT) enables us to produce offspring without germ cells, that is, to 'passage' a unique diploid genome. Animal cloning has also proven to be a powerful research tool for reprogramming in many mammals, notably mouse and cow. The mechanism underlying reprogramming, however, remains largely unknown and, animal cloning has been inefficient as a result. More momentously, in addition to abortion and fetal mortality, some cloned animals display possible premature aging phenotypes including early death and short telomere lengths. Under these inauspicious conditions, is it really possible for SCNT to preserve a diploid genome? Delightfully, in mouse and recently in primate, using SCNT we can produce nuclear transfer ES cells (ntES) more efficiently, which can preserve the eternal lifespan for the 'passage' of a unique diploid genome. Further, new somatic cloning technique using histone-deacetylase inhibitors has been developed which can significantly increase the previous cloning rates two to six times. Here, we introduce SCNT and its value as a preservation tool for a diploid genome while reviewing aging of cloned animals on cellular and individual levels.

  19. Nuclear transfer procedures in the ovine can induce early embryo fragmentation and compromise cloned embryo development.

    PubMed

    Xue, Lian; Cheng, Lei; Su, Guanghua; Kang, Feng; Wu, Xia; Bai, Chunling; Zhang, Li; Li, Guang-Peng

    2011-07-01

    Cytoplasmic fragmentations are frequently observed in early mammalian embryos, and especially in the human. In our research we have observed subtle clues that the occurrence of fragmentation was most likely a result of somatic cell nuclear transfer (NT) protocols, and in particular, the in vitro culture system. In this study we examined various putative factors that might induce early embryo fragmentation in the ovine. The results indicate that nuclear transfer protocols such as the fusion parameter, activation treatment, and especially the choice of culture medium affected embryo cleavage rates and resulted in a higher incidence of fragmented embryos. Upon using the same fusion parameter, activation parameters that were based upon amino acids containing synthetic oviduct fluids (SOFaa) culture system resulted in significantly lower fragmentation rates than when utilizing a Charles Rosenkrans 1 (CR1aa) culture system. Fragmented embryos typically exhibited irregular numbers of blastomeres with the majority of blastomeres devoid of chromatin. Factors such as fusion DC pulse, activation treatment and culture system led to higher fragmentation and also affected in vitro and in vivo embryo development. The SOFaa based culture system produced a higher number of quality NT embryos resulting in higher pregnancy rates and the birth of live lambs as compared to the CR1aa based system (P<0.05). We conclude that early embryo fragmentation in the ovine is caused by suboptimal cloning protocols, and NT embryo development is especially affected by the culture system used. PMID:21700405

  20. Distribution and interspecies contact of feral swine and cattle on rangeland in south Texas: implications for disease transmission.

    PubMed

    Cooper, Susan M; Scott, H Morgan; de la Garza, Guadalupe R; Deck, Aubrey L; Cathey, James C

    2010-01-01

    The last outbreak of foot-and-mouth disease (FMD) in the United States occurred in 1929. Since that time, numbers and distribution of feral swine (Sus scrofa) have increased greatly, especially in the southern states. This creates a potential risk to livestock production because swine are susceptible to, and can be carriers of, several economically harmful diseases of livestock. Most importantly, swine are potent amplifiers of FMD virus. In this study, global positioning system (GPS) collars were placed on rangeland cattle (Bos indicus x taurus) and feral swine to determine shared habitat use by these species on a large ranch in south Texas from 2004 to 2006. The aim was to identify locations and rates of interspecies contact that may result in effective transfer of FMD virus, should an outbreak occur. In shrubland and riparian areas, animals were dispersed, so contacts within and between species were relatively infrequent. Indirect contacts, whereby cattle and feral swine used the same location (within 20 m) within a 360-min period, occurred primarily at water sources, and seasonally in irrigated forage fields and along ranch roads. Direct contacts between species (animals <20 m apart and within 15 min) were rare and occurred primarily at water sources. Changes in ranch management practices are suggested to reduce interspecies contact should an FMD disease outbreak occur. This information can also be used to improve current epidemiologic models to better fit free-ranging animal populations. PMID:20090028

  1. Transfer of 137Cs from Chernobyl debris and nuclear weapons fallout to different Swedish population groups.

    PubMed

    Rääf, C L; Hubbard, L; Falk, R; Agren, G; Vesanen, R

    2006-08-15

    Data from measurements on the body burden of (134)Cs, (137)Cs and (40)K in various Swedish populations between 1959 and 2001 has been compiled into a national database. The compilation is a co-operation between the Departments of Radiation Physics in Malmö and Göteborg, the National Radiation Protection Authority (SSI) and the Swedish Defense Research Agency (FOI). In a previous study the effective ecological half time and the associated effective dose to various Swedish populations due to internal contamination of (134)Cs and (137)Cs have been assessed using the database. In this study values of human body burden have been combined with data on the local and regional ground deposition of fallout from nuclear weapons tests (only (137)Cs) and Chernobyl debris (both (134)Cs and (137)Cs), which have enabled estimates of the radioecological transfer in the studied populations. The assessment of the database shows that the transfer of radiocesium from Chernobyl fallout to humans varies considerably between various populations in Sweden. In terms of committed effective dose over a 70 y period from internal contamination per unit activity deposition, the general (predominantly urban) Swedish population obtains 20-30 microSv/kBq m(-2). Four categories of populations exhibit higher radioecological transfer than the general population; i.) reindeer herders ( approximately 700 microSv/kBq m(-2)), ii.) hunters in the counties dominated by forest vegetation ( approximately 100 microSv/kBq m(-2)), iii.) rural non-farming populations living in sub-arctic areas (40-150 microSv/kBq m(-2)), and iv.) farmers ( approximately 50 microSv/kBq m(-2)). Two important factors determine the aggregate transfer from ground deposition to man; i.) dietary habits (intakes of foodstuff originating from natural and semi-natural ecosystems), and ii.) inclination to follow the recommended food restriction by the authorities. The transfer to the general population is considerably lower

  2. Unusual horizontal transfer of a long interspersed nuclear element between distant vertebrate classes.

    PubMed

    Kordis, D; Gubensek, F

    1998-09-01

    We have shown previously by Southern blot analysis that Bov-B long interspersed nuclear elements (LINEs) are present in different Viperidae snake species. To address the question as to whether Bov-B LINEs really have been transmitted horizontally between vertebrate classes, the analysis has been extended to a larger number of vertebrate, invertebrate, and plant species. In this paper, the evolutionary origin of Bov-B LINEs is shown unequivocally to be in Squamata. The previously proposed horizontal transfer of Bov-B LINEs in vertebrates has been confirmed by their discontinuous phylogenetic distribution in Squamata (Serpentes and two lizard infra-orders) as well as in Ruminantia, by the high level of nucleotide identity, and by their phylogenetic relationships. The horizontal transfer of Bov-B LINEs from Squamata to the ancestor of Ruminantia is evident from the genetic distances and discontinuous phylogenetic distribution. The ancestor of Colubroidea snakes is a possible donor of Bov-B LINEs to Ruminantia. The timing of horizontal transfer has been estimated from the distribution of Bov-B LINEs in Ruminantia and the fossil data of Ruminantia to be 40-50 My ago. The phylogenetic relationships of Bov-B LINEs from the various Squamata species agrees with that of the species phylogeny, suggesting that Bov-B LINEs have been maintained stably by vertical transmission since the origin of Squamata in the Mesozoic era. PMID:9724768

  3. Application of Direct Assessment Approaches and Methodologies to Cathodically Protected Nuclear Waste Transfer Lines

    SciTech Connect

    Dahl, Megan M.; Pikas, Joseph; Edgemon, Glenn L.; Philo, Sarah

    2013-01-22

    The U.S. Department of Energy's (DOE) Hanford Site is responsible for the safe storage, retrieval, treatment, and disposal of approximately 54 million gallons (204 million liters) of radioactive waste generated since the site's inception in 1943. Today, the major structures involved in waste management at Hanford include 149 carbon steel single-shell tanks, 28 carbon-steel double-shell tanks, plus a network of buried metallic transfer lines and ancillary systems (pits, vaults, catch tanks, etc.) required to store, retrieve, and transfer waste within the tank farm system. Many of the waste management systems at Hanford are still in use today. In response to uncertainties regarding the structural integrity of these systems,' an independent, comprehensive integrity assessment of the Hanford Site piping system was performed. It was found that regulators do not require the cathodically protected pipelines located within the Hanford Site to be assessed by External Corrosion Direct Assessment (ECDA) or any other method used to ensure integrity. However, a case study is presented discussing the application of the direct assessment process on pipelines in such a nuclear environment. Assessment methodology and assessment results are contained herein. An approach is described for the monitoring, integration of outside data, and analysis of this information in order to identify whether coating deterioration accompanied by external corrosion is a threat for these waste transfer lines.

  4. Piglets born from vitrified cloned blastocysts produced with a simplified method of delipation and nuclear transfer.

    PubMed

    Du, Yutao; Li, Juan; Kragh, Peter M; Zhang, Yunhai; Schmidt, Mette; Bøgh, Ingrid B; Zhang, Xiuqing; Purup, Stig; Kuwayama, M; Jørgensen, Arne L; Pedersen, Anette M; Villemoes, Klaus; Yang, Huanming; Bolund, Lars; Vajta, Gábor

    2007-01-01

    Successful cryopreservation of porcine embryos offers a promising perspective in the fields of agriculture, animal science, and human medical research. The objective of the present work was to establish a system facilitating the cryopreservation of porcine embryos produced by somatic cell nuclear transfer (SCNT). Several key techniques including micromanipulator-based enucleation, noninvasive delipation, zona-free fusion, and activation were combined with high efficiency. After a partial zona digestion and high-speed centrifugation, 89.8+/-2.1% (mean+/-SEM) of enucleated oocytes were successfully delipated. Delipated cytoplasts were incubated for an additional 0.5 or 2 h before fusion with somatic cells. After activation and 6 days of in vitro culture, no significant difference in the rate of blastocysts per reconstructed embryo was observed between the two groups (33.1+/-1.8% and 26.0+/-4.3% for 0.5 and 2 h recovery time, respectively). Cryopreservation of the blastocysts was performed with a Cryotop device and factory-prepared vitrification and warming solutions. One hundred fifty-five vitrified SCNT embryos were transferred surgically into two recipient sows to test their developmental capacity in vivo. One recipient became pregnant and delivered six piglets. In conclusion, our simplified delipation and SCNT procedure resulted in viable piglets after vitrification and embryo transfer at the blastocyst stage. PMID:18154508

  5. Interspecies communication between plant and mouse gut host cells through edible plant derived exosome-like nanoparticles

    PubMed Central

    Mu, Jingyao; Zhuang, Xiaoying; Wang, Qilong; Jiang, Hong; Deng, Zhong-Bin; Wang, Baomei; Zhang, Lifeng; Kakar, Sham; Jun, Yan; Miller, Donald; Zhang, Huang-Ge

    2015-01-01

    Scope Exosomes, small vesicles participating in intercellular communication have been extensively studied recently; however, the role of edible plant derived exosomes in interspecies communication has not been investigated. Here, we investigate the biological effects of edible plant derived exosome-like nanoparticles (EPDEN) on mammalian cells. Methods and results In this study, exosome-like nanoparticles from four edible plants were isolated and characterized. We show that these EPDENs contain proteins, lipids and microRNA. EPDENs are taken up by intestinal macrophages and stem cells. The results generated from EPDEN transfected macrophages indicate that ginger EPDENs preferentially induce the expression of the anti-oxidation gene, heme oxygenase-1 (HO-1) and the anti-inflammatory cytokine, IL-10; whereas grapefruit, ginger, and carrot EPDENs promote activation of nuclear factor (erythroid-derived 2)-like 2 (Nrf2). Furthermore, analysis of the intestines of canonical Wnt reporter mice, i.e., B6.Cg-Tg(BAT-lacZ)3Picc/J mice, revealed that the numbers of β-galactosidase+ (β-Gal) intestinal crypts are increased, suggesting that EPDEN treatment of mice leads to Wnt mediated activation of the Tcf4 transcription machinery in the crypts. Conclusion The data suggest a role for EPDEN mediated interspecies communication by inducing expression of genes for anti-inflammation cytokines, anti-oxidation and activation of Wnt signaling, which are crucial for maintaining intestinal homeostasis. PMID:24842810

  6. International remote monitoring project Argentina Nuclear Power Station Spent Fuel Transfer Remote Monitoring System

    SciTech Connect

    Schneider, S.; Lucero, R.; Glidewell, D.

    1997-08-01

    The Autoridad Regulataria Nuclear (ARN) and the United States Department of Energy (DOE) are cooperating on the development of a Remote Monitoring System for nuclear nonproliferation efforts. A Remote Monitoring System for spent fuel transfer will be installed at the Argentina Nuclear Power Station in Embalse, Argentina. The system has been designed by Sandia National Laboratories (SNL), with Los Alamos National Laboratory (LANL) and Oak Ridge National Laboratory (ORNL) providing gamma and neutron sensors. This project will test and evaluate the fundamental design and implementation of the Remote Monitoring System in its application to regional and international safeguards efficiency. This paper provides a description of the monitoring system and its functions. The Remote Monitoring System consists of gamma and neutron radiation sensors, RF systems, and video systems integrated into a coherent functioning whole. All sensor data communicate over an Echelon LonWorks Network to a single data logger. The Neumann DCM 14 video module is integrated into the Remote Monitoring System. All sensor and image data are stored on a Data Acquisition System (DAS) and archived and reviewed on a Data and Image Review Station (DIRS). Conventional phone lines are used as the telecommunications link to transmit on-site collected data and images to remote locations. The data and images are authenticated before transmission. Data review stations will be installed at ARN in Buenos Aires, Argentina, ABACC in Rio De Janeiro, IAEA Headquarters in Vienna, and Sandia National Laboratories in Albuquerque, New Mexico. 2 refs., 2 figs.

  7. The influence of donor nucleus source on the outcome of zebrafish somatic cell nuclear transfer.

    PubMed

    Siripattarapravat, Kannika; Pinmee, Boonya; Chang, Eun-Ah; Muñoz, Juan D; Kawakami, Koichi; Cibelli, José B

    2010-01-01

    The success of nuclear reprogramming following somatic cell nuclear transfer (SCNT) is thought to depend on factors present in the egg. Little is known about the role - if any - played by the somatic cell type on the outcome of the procedure. We tested whether cells of different lineages might have different capacities for reprogramming following SCNT, comparing cells isolated from five different tissues of transgenic zebrafish for their developmental potential when used as SCNT donor cells. We used transgenic zebrafish lines expressing green fluorescence protein under an endogenous tissue-specific promoter: HGn62A-skin, HGn28A-skin, HGn8E-heart, HG21C-fin and notochord and HGn30A-hatch gland. We analyzed the efficiency of cloning, as measured by reconstructed embryos that developed up to the hatched-fry stage. Specifically, donor cells of fin and notochord origin yielded the best rate of cloned fish production. All of the other cell types used were capable of producing cloned fish, albeit with significantly lower efficiency. These results indicate that the type of zebrafish cells used for SCNT can influence the outcome of the procedure. Future epigenetic analysis of these cells will help determine specific chromatin profiles in somatic cells that have an impact on nuclear reprogramming procedures. PMID:21404188

  8. Heat Transfer Enhancement By Three-Dimensional Surface Roughness Technique In Nuclear Fuel Rod Bundles

    NASA Astrophysics Data System (ADS)

    Najeeb, Umair

    This thesis experimentally investigates the enhancement of single-phase heat transfer, frictional loss and pressure drop characteristics in a Single Heater Element Loop Tester (SHELT). The heater element simulates a single fuel rod for Pressurized Nuclear reactor. In this experimental investigation, the effect of the outer surface roughness of a simulated nuclear rod bundle was studied. The outer surface of a simulated fuel rod was created with a three-dimensional (Diamond-shaped blocks) surface roughness. The angle of corrugation for each diamond was 45 degrees. The length of each side of a diamond block is 1 mm. The depth of each diamond block was 0.3 mm. The pitch of the pattern was 1.614 mm. The simulated fuel rod had an outside diameter of 9.5 mm and wall thickness of 1.5 mm and was placed in a test-section made of 38.1 mm inner diameter, wall thickness 6.35 mm aluminum pipe. The Simulated fuel rod was made of Nickel 200 and Inconel 625 materials. The fuel rod was connected to 10 KW DC power supply. The Inconel 625 material of the rod with an electrical resistance of 32.3 kO was used to generate heat inside the test-section. The heat energy dissipated from the Inconel tube due to the flow of electrical current flows into the working fluid across the rod at constant heat flux conditions. The DI water was employed as working fluid for this experimental investigation. The temperature and pressure readings for both smooth and rough regions of the fuel rod were recorded and compared later to find enhancement in heat transfer coefficient and increment in the pressure drops. Tests were conducted for Reynold's Numbers ranging from 10e4 to 10e5. Enhancement in heat transfer coefficient at all Re was recorded. The maximum heat transfer co-efficient enhancement recorded was 86% at Re = 4.18e5. It was also observed that the pressure drop and friction factor increased by 14.7% due to the increased surface roughness.

  9. Effect of epigenetic modification with trichostatin A and S-adenosylhomocysteine on developmental competence and POU5F1-EGFP expression of interspecies cloned embryos in dog.

    PubMed

    Mousai, M; Hosseini, S M; Hajian, M; Jafarpour, F; Asgari, V; Forouzanfar, M; Nasr-Esfahani, M H

    2015-10-01

    Adult canine fibroblasts stably transfected with either cytomegalovirus (CMV) or POU5F1 promoter-driven enhanced green fluorescent protein (EGFP) were used to investigate if pre-treatment of these donor cells with two epigenetic drugs [trichostatin A (TSA), or S-adenosylhomocysteine (SAH)] can improve the efficiency of interspecies somatic cell nuclear transfer (iSCNT). Fluorescence-activated cell sorting (FACS), analyses revealed that TSA, but not SAH, treatment of both transgenic and non-transgenic fibroblasts significantly increased acetylation levels compared with untreated relatives. The expression levels of Bcl2 and P53 were significantly affected in TSA-treated cells compared with untreated cells, whereas SAH treatment had no significant effect on cell apoptosis. Irrespective of epigenetic modification, dog/bovine iSCNT embryos had overall similar rates of cleavage and development to 8-16-cell and morula stages in non-transgenic groups. For transgenic reconstructed embryos, however, TSA and SAH could significantly improve development to 8-16-cell and morula stages compared with control. Even though, irrespective of cell transgenesis and epigenetic modification, none of the iSCNT embryos developed to the blastocyst stage. The iSCNT embryos carrying CMV-EGFP expressed EGFP at all developmental stages (2-cell, 4-cell, 8-16-cell, and morula) without mosaicism, while no POU5F1-EGFP signal was observed in any stage of developing iSCNT embryos irrespective of TSA/SAH epigenetic modifications. These results indicated that bovine oocytes partially remodel canine fibroblasts and that TSA and SAH have marginal beneficial effects on this process. PMID:25314965

  10. Interspecies recombination between enterococci: genetic and phenotypic diversity of vancomycin-resistant transconjugants.

    PubMed

    McAshan, S K; Vergin, K L; Giovannoni, S J; Thaler, D S

    1999-01-01

    recipient and donor strains used in transconjugation experiments were different species. Sequence analysis was also used to consider the possibility that rRNA operons might be mobilized in conjugation, but no evidence for the transfer of rDNA operons was found. An apparent insertion sequence in E. faecium almost identical to IS 1485 and 57% sequence identity to IS 199 of Streptococcus mutans was found in the region of DNA transferred. The results imply new consequences of conjugative transfer and interspecies recombination. PMID:10432271

  11. In vitro development of canine somatic cell nuclear transfer embryos in different culture media.

    PubMed

    Kim, Dong-Hoon; No, Jin-Gu; Choi, Mi-Kyung; Yeom, Dong-Hyeon; Kim, Dong-Kyo; Yang, Byoung-Chul; Yoo, Jae Gyu; Kim, Min Kyu; Kim, Hong-Tea

    2015-01-01

    The objective of the present study was to investigate the effects of three different culture media on the development of canine somatic cell nuclear transfer (SCNT) embryos. Canine cloned embryos were cultured in modified synthetic oviductal fluid (mSOF), porcine zygote medium-3 (PZM-3), or G1/G2 sequential media. Our results showed that the G1/G2 media yielded significantly higher morula and blastocyst development in canine SCNT embryos (26.1% and 7.8%, respectively) compared to PZM-3 (8.5% and 0%or mSOF (2.3% and 0%) media. In conclusion, this study suggests that blastocysts can be produced more efficiently using G1/G2 media to culture canine SCNT embryos. PMID:25549216

  12. Murine somatic cell nuclear transfer using reprogrammed donor cells expressing male germ cell-specific genes.

    PubMed

    Kang, Hoin; Park, Jong Im; Roh, Sangho

    2016-01-01

    In vivo-matured mouse oocytes were enucleated, and a single murine embryonic fibroblast (control or reprogrammed by introducing extracts from murine testis tissue, which showed expression of male germ cell-specific genes) was injected into the cytoplasm of the oocytes. The rate of blastocyst development and expression levels of Oct-4, Eomes and Cdx-2 were not significantly different in both experimental groups. However, the expression levels of Nanog, Sox9 and Glut-1 were significantly increased when reprogrammed cells were used as donor nuclei. Increased expression of Nanog can be supportive of complete reprogramming of somatic cell nuclear transfer murine embryos. The present study suggested that donor cells expressing male germ cell-specific genes can be reconstructed and can develop into embryos with normal high expression of developmentally essential genes. PMID:26369430

  13. In vitro development of canine somatic cell nuclear transfer embryos in different culture media

    PubMed Central

    No, Jin-Gu; Choi, Mi-Kyung; Yeom, Dong-Hyeon; Kim, Dong-Kyo; Yang, Byoung-Chul; Yoo, Jae Gyu; Kim, Min Kyu; Kim, Hong-Tea

    2015-01-01

    The objective of the present study was to investigate the effects of three different culture media on the development of canine somatic cell nuclear transfer (SCNT) embryos. Canine cloned embryos were cultured in modified synthetic oviductal fluid (mSOF), porcine zygote medium-3 (PZM-3), or G1/G2 sequential media. Our results showed that the G1/G2 media yielded significantly higher morula and blastocyst development in canine SCNT embryos (26.1% and 7.8%, respectively) compared to PZM-3 (8.5% and 0%) or mSOF (2.3% and 0%) media. In conclusion, this study suggests that blastocysts can be produced more efficiently using G1/G2 media to culture canine SCNT embryos. PMID:25549216

  14. Femtosecond laser based enucleation of porcine oocytes for somatic cell nuclear transfer

    NASA Astrophysics Data System (ADS)

    Kütemeyer, K.; Lucas-Hahn, A.; Petersen, B.; Hassel, P.; Lemme, E.; Niemann, H.; Heisterkamp, A.

    2009-07-01

    Cloning of several mammalian species has been achieved by somatic cell nuclear transfer (SCNT) in recent years. However, this method still results in very low efficiencies around 1% which originate from suboptimal culture conditions and highly invasive techniques for oocyte enucleation and injection of the donor cell using micromanipulators. In this paper, we present a new minimal invasive method for oocyte imaging and enucleation based on the application of femtosecond (fs) laser pulses. After imaging of the oocyte with multiphoton microscopy, ultrashort pulses are focused onto the metaphase plate of MII-oocytes in order to ablate the DNA molecules. We show that fs laser based enucleation of porcine oocytes completely inhibits the first mitotic cleavage after parthenogenetic activation while maintaining intact oocyte morphology in most cases. In contrast, control groups without previous irradiation of the metaphase plate are able to develop to the blastocyst stage. Further experiments have to clarify the suitability of fs laser based enucleated oocytes for SCNT.

  15. Heat transfer effects in vertically emplaced high level nuclear waste container

    SciTech Connect

    Moujaes, S.F.; Lei, Y.M.

    1994-05-01

    Modeling free convection heat transfer in an cylindrical annular enclosure is still an active area of research and an important problem to be addressed in the high level nuclear waste repository. For the vertically emplaced waste container, the air gap which is between the container shell and the rock borehole, have an important role of dissipating heat to surrounding rack. These waste containers are vertically emplaced in the borehole 300 meters below ground, and in a horizontal grid of 30 {times} 8 meters apart. The borehole will be capped after the container emplacement. The expected initial heat generated is between 3--4.74 kW per container depending on the type of waste. The goal of this study is to use a computer simulation model to find the borehole wall, air-gap and the container outer wall temperature distributions.

  16. Modeling Electronic-Nuclear Interactions for Excitation Energy Transfer Processes in Light-Harvesting Complexes.

    PubMed

    Lee, Mi Kyung; Coker, David F

    2016-08-18

    An accurate approach for computing intermolecular and intrachromophore contributions to spectral densities to describe the electronic-nuclear interactions relevant for modeling excitation energy transfer processes in light harvesting systems is presented. The approach is based on molecular dynamics (MD) calculations of classical correlation functions of long-range contributions to excitation energy fluctuations and a separate harmonic analysis and single-point gradient quantum calculations for electron-intrachromophore vibrational couplings. A simple model is also presented that enables detailed analysis of the shortcomings of standard MD-based excitation energy fluctuation correlation function approaches. The method introduced here avoids these problems, and its reliability is demonstrated in accurate predictions for bacteriochlorophyll molecules in the Fenna-Matthews-Olson pigment-protein complex, where excellent agreement with experimental spectral densities is found. This efficient approach can provide instantaneous spectral densities for treating the influence of fluctuations in environmental dissipation on fast electronic relaxation. PMID:27472379

  17. Bioactive conformation of stromelysin inhibitors determined by transferred nuclear Overhauser effects.

    PubMed Central

    Gonnella, N C; Bohacek, R; Zhang, X; Kolossváry, I; Paris, C G; Melton, R; Winter, C; Hu, S I; Ganu, V

    1995-01-01

    The transferred nuclear Overhauser effect has been used to determine the biologically active conformations of two stromelysin inhibitors. Both inhibitors used in this study were hydroxamic acids generated via chemical synthesis. These structures, representing the conformation of each inhibitor bound to stromelysin, superimposed with excellent agreement. The study also provided information on the shape and orientation of the S2' and S1' pockets of the enzyme relative to thermolysin. Comparisons were made between stromelysin and thermolysin inhibitors to critically examine thermolysin as a template for stromelysin-inhibitor design. The enzyme-bound conformations of these stromelysin inhibitors were determined for use as a template in conformationally restricted drug design. Images Fig. 4 Fig. 5 Fig. 6 Fig. 7 PMID:7831311

  18. Live embryo imaging to follow cell cycle and chromosomes stability after nuclear transfer.

    PubMed

    Balbach, Sebastian T; Boiani, Michele

    2015-01-01

    Nuclear transfer (NT) into mouse oocytes yields a transcriptionally and functionally heterogeneous population of cloned embryos. Most studies of NT embryos consider only embryos at predefined key stages (e.g., morula or blastocyst), that is, after the bulk of reprogramming has taken place. These retrospective approaches are of limited use to elucidate mechanisms of reprogramming and to predict developmental success. Observing cloned embryo development using live embryo cinematography has the potential to reveal otherwise undetectable embryo features. However, light exposure necessary for live cell cinematography is highly toxic to cloned embryos. Here we describe a protocol for combined bright-field and fluorescence live-cell imaging of histone H2b-GFP expressing mouse embryos, to record cell divisions up to the blastocyst stage. This protocol, which can be adapted to observe other reporters such as Oct4-GFP or Nanog-GFP, allowed us to quantitatively analyze cleavage kinetics of cloned embryos. PMID:25287344

  19. Development of Species Sensitivity Distributions for Wildlife Using Interspecies Toxicity Correlation Models

    EPA Science Inventory

    Species sensitivity distributions (SSD) are cumulative distributions of chemical toxicity of multiple species and have had limited application in wildlife risk assessment because of relatively small datasets of wildlife toxicity values. Interspecies correlation estimation (ICE) m...

  20. ESTIMATION OF CHEMICAL TOXICITY TO WILDLIFE SPECIES USING INTERSPECIES CORRELATION MODELS

    EPA Science Inventory

    Ecological risks to wildlife are typically assessed using toxicity data for relataively few species and with limited understanding of differences in species sensitivity to contaminants. Empirical interspecies correlation models were derived from LD50 values for 49 wildlife speci...

  1. ESTIMATION OF AQUATIC SPECIES SENSITIVITY USING INTERSPECIES CORRELATION AND ACUTE TO CHRONIC TOXICITY MODELS

    EPA Science Inventory

    Abstract for presentation

    Estimation of aquatic species sensitivity using interspecies correlation and acute to chronic toxicity models

    Determining species sensitivity of aquatic organisms to contaminants is a critical component of criteria development and ecolog...

  2. INTER-SPECIES MODELS FOR ACUTE AQUATIC TOXICITY BASED ON MECHANISM OF ACTION

    EPA Science Inventory

    This presentation will provide interspecies QSARs for acute toxicity to 17 aquatic species, such as fish, snail, tadpole, hydrozoan, crustacean, insect larvae, and bacteria developed using 5,000 toxic effect results for approximately 2400 chemicals.

  3. Deficiency of Genomic Reprogramming in Trophoblast Stem Cells Following Nuclear Transfer

    PubMed Central

    Watanabe, Hiroyuki; Fukuda, Atsushi; Kono, Tomohiro

    2015-01-01

    Abstract To examine the genomic reprogrammability of trophoblast stem (TS) cells using a nuclear transfer technique, we produced TS cloned embryos using five TS cell lines from three strains of mice (ICR, B6D2F1, and B6CBF1) as donors and observed developmental ability during preimplantation development. The developmental rates of the TS cloned embryos that developed to the two-cell, four- to eight-cell, morula, and blastocyst stages were 58–83%, 0–38.6%, 0–21.3%, and 0–15.9%, respectively, indicating that more than 50% of TS cloned embryos arrested at the two-cell stage. These TS cloned two-cell embryos were expressed low level of Dappa3 (also known as PGC7/Stella), indicating that zygotic gene activation (ZGA) was disrupted in these embryos. However, a small portion of the TS cloned embryos (0–15.9%) reached the blastocyst stage. In these TS cloned blastocysts, the numbers of trophectoderm (TE) and inner cell mass (ICM) cells were 31.9±4.6 and 12.1±3.0, respectively, which were not significantly different from those in the fertilized embryos. In addition, the gene expression analysis showed that Oct3/4, and Cdx2, which are ICM- and TE-specific marker genes, respectively, and Dppa3, and Hdac1, which are zygotic gene activation-related genes, were expressed in TS cloned blastocysts at the same levels as in the fertilized blastocysts. These results indicate that although TS cloned embryos are able to differentiate into ICM cells, the genomic reprogrammability of TS cells is very low following nuclear transfer. PMID:25826724

  4. Spent Nuclear Fuel Dry Transfer System Cold Demonstration Project Final Report

    SciTech Connect

    Christensen, Max R; McKinnon, M. A.

    1999-12-01

    The spent nuclear fuel dry transfer system (DTS) provides an interface between large and small casks and between storage-only and transportation casks. It permits decommissioning of reactor pools after shutdown and allows the use of large storage-only casks for temporary onsite storage of spent nuclear fuel irrespective of reactor or fuel handling limitations at a reactor site. A cold demonstration of the DTS prototype was initiated in August 1996 at the Idaho National Engineering and Environmental Laboratory (INEEL). The major components demonstrated included the fuel assembly handling subsystem, the shield plug/lid handling subsystem, the cask interface subsystem, the demonstration control subsystem, a support frame, and a closed circuit television and lighting system. The demonstration included a complete series of DTS operations from source cask receipt and opening through fuel transfer and closure of the receiving cask. The demonstration included both normal operations and recovery from off-normal events. It was designed to challenge the system to determine whether there were any activities that could be made to jeopardize the activities of another function or its safety. All known interlocks were challenged. The equipment ran smoothly and functioned as designed. A few "bugs" were corrected. Prior to completion of the demonstration testing, a number of DTS prototype systems were modified to apply lessons learned to date. Additional testing was performed to validate the modifications. In general, all the equipment worked exceptionally well. The demonstration also helped confirm cost estimates that had been made at several points in the development of the system.

  5. Exploiting level anti-crossings for efficient and selective transfer of hyperpolarization in coupled nuclear spin systems.

    PubMed

    Pravdivtsev, Andrey N; Yurkovskaya, Alexandra V; Kaptein, Robert; Miesel, Karsten; Vieth, Hans-Martin; Ivanov, Konstantin L

    2013-09-21

    Spin hyperpolarization can be coherently transferred to other nuclei in field-cycling NMR experiments. At low magnetic fields spin polarization is redistributed in a strongly coupled network of spins. Polarization transfer is most efficient at fields where level anti-crossings (LACs) occur for the nuclear spin-states. A further condition is that field switching to the LAC positions is non-adiabatic in order to convert the starting population differences into spin coherences that cause time-dependent mixing of states. The power of this method has been demonstrated by studying transfer of photo-Chemically Induced Dynamic Nuclear Polarization (photo-CIDNP) in N-acetyl-tryptophan. We have investigated the magnetic field dependence and time dependence of coherent CIDNP transfer and directly assessed nuclear spin LACs by studying polarization transfer at specific field positions. The proposed approach based on LACs is not limited to CIDNP but is advantageous for enhancing NMR signals by spin order transfer from any type of hyper-polarized nuclei. PMID:23893009

  6. Phenotypes of Aging Postovulatory Oocytes After Somatic Cell Nuclear Transfer in Mice.

    PubMed

    Lee, Ah Reum; Shimoike, Takashi; Wakayama, Teruhiko; Kishigami, Satoshi

    2016-06-01

    Oocytes rapidly lose their developmental potential after ovulation, termed postovulatory oocyte aging, and often exhibit characteristic phenotypes, such as cytofragmentation, abnormal spindle shapes, and chromosome misalignments. Here, we reconstructed mouse oocytes using somatic cell nuclear transfer (SCNT) to reveal the effect of somatic cell-derived nuclei on oocyte physiology during aging. Normal oocytes started undergoing cytofragmentation 24 hours after oocyte collection; however, this occurred earlier in SCNT oocytes and was more severe at 48 hours, suggesting that the transferred somatic cell nuclei affected oocyte physiology. We found no difference in the status of acetylated α-tubulin (Ac-Tub) and α-tubulin (Tub) between normal and SCNT aging oocytes, but unlike normal oocytes, aging SCNT oocytes did not have astral microtubules. Interestingly, aging SCNT oocytes displayed more severely scattered chromosomes or irregularly shaped spindles. Observations of the microfilaments showed that, in normal oocytes, there was a clear actin ring beneath the plasma membrane and condensed microfilaments around the spindle (the actin cap) at 0 hours, and the actin filaments started degenerating at 1 hour, becoming completely disrupted and distributed to the cytoplasm at 24 hours. By contrast, in SCNT oocytes, an actin cap formed around the transplanted nuclei within 1 hour of SCNT, which was still present at 24 hours. Thus, SCNT oocytes age in a similar but distinct way, suggesting that they not only contain nuclei with abnormal epigenetics but are also physiologically different. PMID:27253626

  7. Production of human apolipoprotein(a) transgenic NIBS miniature pigs by somatic cell nuclear transfer.

    PubMed

    Shimatsu, Yoshiki; Horii, Wataru; Nunoya, Tetsuo; Iwata, Akira; Fan, Jianglin; Ozawa, Masayuki

    2016-01-01

    Most cases of ischemic heart disease and stroke occur as a result of atherosclerosis. The purpose of this study was to produce a new Nippon Institute for Biological Science (NIBS) miniature pig model by somatic cell nuclear transfer (SCNT) for studying atherosclerosis. The human apolipoprotein(a) (apo(a)) genes were transfected into kidney epithelial cells derived from a male and a female piglet. Male cells were used as donors initially, and 275 embryos were transferred to surrogates. Three offspring were delivered, and the production efficiency was 1.1% (3/275). Serial female cells were injected into 937 enucleated oocytes. Eight offspring were delivered (production efficiency: 0.9%) from surrogates. One male and 2 female transgenic miniature pigs matured well. Lipoprotein(a) was found in the male and one of the female transgenic animals. These results demonstrate successful production of human apo(a) transgenic NIBS miniature pigs by SCNT. Our goal is to establish a human apo(a) transgenic NIBS miniature pig colony for studying atherosclerosis. PMID:26411321

  8. Faddeev-type calculation of (d ,n ) transfer reactions in three-body nuclear systems

    NASA Astrophysics Data System (ADS)

    Deltuva, A.

    2015-12-01

    Exact Faddeev-type three-body equations are applied to the study of the proton transfer reactions (d ,n ) in the system consisting of a nuclear core and two nucleons. The integral equations for the three-body transition operators are solved in the momentum-space framework including the Coulomb interaction via the screening and renormalization method. For a weakly bound final nucleus the calculation of the (d ,n ) reaction is more demanding in terms of the screening radius as compared to the (d ,p ) reaction. Well-converged differential cross section results are obtained for 7Be (d ,n ) 8B, 12C (d ,n ) 13N, and 16O (d ,n ) 17$ reactions. A comparison with the corresponding (d ,p ) reactions is made. The calculations fail to reproduce the shape of the angular distribution for reactions on 12C but provide quite successful description for reactions on 16O, especially for the transfer to the 17F excited state 1 /2+ when using a nonlocal optical potential.

  9. Production of human apolipoprotein(a) transgenic NIBS miniature pigs by somatic cell nuclear transfer

    PubMed Central

    Shimatsu, Yoshiki; Horii, Wataru; Nunoya, Tetsuo; Iwata, Akira; Fan, Jianglin; Ozawa, Masayuki

    2015-01-01

    Most cases of ischemic heart disease and stroke occur as a result of atherosclerosis. The purpose of this study was to produce a new Nippon Institute for Biological Science (NIBS) miniature pig model by somatic cell nuclear transfer (SCNT) for studying atherosclerosis. The human apolipoprotein(a) (apo(a)) genes were transfected into kidney epithelial cells derived from a male and a female piglet. Male cells were used as donors initially, and 275 embryos were transferred to surrogates. Three offspring were delivered, and the production efficiency was 1.1% (3/275). Serial female cells were injected into 937 enucleated oocytes. Eight offspring were delivered (production efficiency: 0.9%) from surrogates. One male and 2 female transgenic miniature pigs matured well. Lipoprotein(a) was found in the male and one of the female transgenic animals. These results demonstrate successful production of human apo(a) transgenic NIBS miniature pigs by SCNT. Our goal is to establish a human apo(a) transgenic NIBS miniature pig colony for studying atherosclerosis. PMID:26411321

  10. Fate of centrosomes following somatic cell nuclear transfer (SCNT) in bovine oocytes.

    PubMed

    Dai, Yunping; Wang, Lili; Wang, Haiping; Liu, Ying; Li, Ning; Lyu, Qifeng; Keefe, David L; Albertini, David F; Liu, Lin

    2006-06-01

    Cloning mammalians by somatic cell nuclear transfer (SCNT) remains inefficient. A majority of clones produced by SCNT fail to develop properly and of those which do survive, some exhibit early aging, premature death, tumors, and other pathologies associated with aneuploidy. Alterations of centrosomes are linked to aberrant cell cycle progression, aneuploidy, and tumorigenesis in many cell types. It remains to be determined how centrosomes are remodeled in cloned bovine embryos. We show that abnormalities in either distribution and/or number of centrosomes were evident in approximately 50% of reconstructed embryos following SCNT. Moreover, centrosome abnormalities and failed 'pronuclear' migration which manifested during the first cell cycle coincided with errors in spindle morphogenesis, chromosome alignment, and cytokinesis. By contrast, nuclear mitotic apparatus protein (NuMA) exhibited normal expression patterns at metaphase spindle poles and in 'pronucleus' during interphase. The defects in centrosome remodeling and 'pronuclear' migration could lead to chromosome instability and developmental failures associated with embryo production by SCNT. Addressing these fundamental problems may enhance production of normal clones. PMID:16735544

  11. Multi-Scale-Structured Composite Coatings by Plasma-Transferred Arc for Nuclear Applications

    NASA Astrophysics Data System (ADS)

    Werry, A.; Chazelas, C.; Denoirjean, A.; Valette, S.; Vardelle, A.; Meillot, E.

    2016-01-01

    In nuclear plants, the replacement of hardfacing Stellite, a cobalt-based alloy, on parts of the piping system in connection with the reactor has been investigated since the late 60's. Various Fe-based or Ni-based alloys, Co-free or with a low content of Co, have been developed but with mechanical properties generally lower than that of Stellites. The 4th generation nuclear plants impose additional or more stringent requirements for hardfacing materials. Plasma-transferred arc (PTA) coatings of cobalt-free nickel-based alloys with the addition of sub-micrometric or micrometric alumina particles are thought to be a potential solution for tribological applications in the primary system of sodium-cooled fast reactors. In this study, PTA coatings of nickel-based alloys reinforced with alumina particles were deposited on 316L stainless steel substrates. Under the conditions of this study, the addition of alumina particles resulted in a refinement of coating microstructure and the improvement of their resistance to abrasive wear. However, it does not bring about any change in coating micro-hardness.

  12. Transfer-induced fission in inverse kinematics: Impact on experimental and evaluated nuclear data bases

    NASA Astrophysics Data System (ADS)

    Farget, F.; Caamaño, M.; Ramos, D.; Rodrıguez-Tajes, C.; Schmidt, K.-H.; Audouin, L.; Benlliure, J.; Casarejos, E.; Clément, E.; Cortina, D.; Delaune, O.; Derkx, X.; Dijon, A.; Doré, D.; Fernández-Domınguez, B.; Gaudefroy, L.; Golabek, C.; Heinz, A.; Jurado, B.; Lemasson, A.; Paradela, C.; Roger, T.; Salsac, M. D.; Schmitt, C.

    2015-12-01

    Inverse kinematics is a new tool to study nuclear fission. Its main advantage is the possibility to measure with an unmatched resolution the atomic number of fission fragments, leading to new observables in the properties of fission-fragment distributions. In addition to the resolution improvement, the study of fission based on nuclear collisions in inverse kinematics beneficiates from a larger view with respect to the neutron-induced fission, as in a single experiment the number of fissioning systems and the excitation energy range are widden. With the use of spectrometers, mass and kinetic-energy distributions may now be investigated as a function of the proton and neutron number sharing. The production of fissioning nuclei in transfer reactions allows studying the isotopic yields of fission fragments as a function of the excitation energy. The higher excitation energy resulting in the fusion reaction leading to the compound nucleus 250Cf at an excitation energy of 45MeV is also presented. With the use of inverse kinematics, the charge polarisation of fragments at scission is now revealed with high precision, and it is shown that it cannot be neglected, even at higher excitation energies. In addition, the kinematical properties of the fragments inform on the deformation configuration at scission.

  13. Inheritance of mitochondrial DNA in serially recloned pigs by somatic cell nuclear transfer (SCNT)

    SciTech Connect

    Do, Minhwa; Jang, Won-Gu; Hwang, Jeong Hee; Jang, Hoon; Kim, Eun-Jung; Jeong, Eun-Jeong; Shim, Hosup; Hwang, Sung Soo; Oh, Keon Bong; Byun, Sung June; Kim, Jin-Hoi; Lee, Jeong Woong

    2012-08-10

    Highlights: Black-Right-Pointing-Pointer We success serial SCNT through the third generation using pig fibroblasts. Black-Right-Pointing-Pointer Donor-specific mtDNA in the recloned pigs was detected. Black-Right-Pointing-Pointer SCNT affect mtDNA mounts. -- Abstract: Somatic cell nuclear transfer (SCNT) has been established for the transmission of specific nuclear DNA. However, the fate of donor mitochondrial DNA (mtDNA) remains unclear. Here, we examined the fate of donor mtDNA in recloned pigs through third generations. Fibroblasts of recloned pigs were obtained from offspring of each generation produced by fusion of cultured fibroblasts from a Minnesota miniature pig (MMP) into enucleated oocytes of a Landrace pig. The D-loop regions from the mtDNA of donor and recipient differ at nucleotide sequence positions 16050 (A{yields}T), 16062 (T{yields}C), and 16135 (G{yields}A). In order to determine the fate of donor mtDNA in recloned pigs, we analyzed the D-loop region of the donor's mtDNA by allele-specific PCR (AS-PCR) and real-time PCR. Donor mtDNA was successfully detected in all recloned offspring (F1, F2, and F3). These results indicate that heteroplasmy that originate from donor and recipient mtDNA is maintained in recloned pigs, resulting from SCNT, unlike natural reproduction.

  14. Interspecies differences in metabolism of arsenic by cultured primary hepatocytes

    SciTech Connect

    Drobna, Zuzana; Walton, Felecia S.; Harmon, Anne W.; Thomas, David J.; Styblo, Miroslav

    2010-05-15

    Biomethylation is the major pathway for the metabolism of inorganic arsenic (iAs) in many mammalian species, including the human. However, significant interspecies differences have been reported in the rate of in vivo metabolism of iAs and in yields of iAs metabolites found in urine. Liver is considered the primary site for the methylation of iAs and arsenic (+3 oxidation state) methyltransferase (As3mt) is the key enzyme in this pathway. Thus, the As3mt-catalyzed methylation of iAs in the liver determines in part the rate and the pattern of iAs metabolism in various species. We examined kinetics and concentration-response patterns for iAs methylation by cultured primary hepatocytes derived from human, rat, mice, dog, rabbit, and rhesus monkey. Hepatocytes were exposed to [{sup 73}As]arsenite (iAs{sup III}; 0.3, 0.9, 3.0, 9.0 or 30 nmol As/mg protein) for 24 h and radiolabeled metabolites were analyzed in cells and culture media. Hepatocytes from all six species methylated iAs{sup III} to methylarsenic (MAs) and dimethylarsenic (DMAs). Notably, dog, rat and monkey hepatocytes were considerably more efficient methylators of iAs{sup III} than mouse, rabbit or human hepatocytes. The low efficiency of mouse, rabbit and human hepatocytes to methylate iAs{sup III} was associated with inhibition of DMAs production by moderate concentrations of iAs{sup III} and with retention of iAs and MAs in cells. No significant correlations were found between the rate of iAs methylation and the thioredoxin reductase activity or glutathione concentration, two factors that modulate the activity of recombinant As3mt. No associations between the rates of iAs methylation and As3mt protein structures were found for the six species examined. Immunoblot analyses indicate that the superior arsenic methylation capacities of dog, rat and monkey hepatocytes examined in this study may be associated with a higher As3mt expression. However, factors other than As3mt expression may also contribute to

  15. Heat Transfer in Waste Glass Melts - Measurement and Implications for Nuclear Waste Vitrification

    NASA Astrophysics Data System (ADS)

    Wang, Chuan

    Thermal properties of waste glass melts, such as high temperature density and thermal conductivity, are relevant to heat transfer processes in nuclear waste vitrification. Experimental measurement techniques were developed and applied to four nuclear waste glasses representative of those currently projected for treatment of Hanford HLW and LAW streams to study heat flow mechanisms in nuclear waste vitrification. Density measurement results by Archimedes' method indicated that densities of the melts investigated varied considerably with composition and temperature. Thermal diffusivities of waste melts were determined at nominal melter operating temperatures using a temperature-wave technique. Thermal conductivities were obtained by combining diffusivity data with the experimentally-acquired densities of the melts and their known heat capacities. The experimental results display quite large positive dependences of conductivities on temperature for some samples and much weaker positive temperature dependences for others. More importantly, there is observed a big change in the slopes of the conductivities versus temperature as temperature is increased for two of the melts, but not for the other two. This behavior was interpreted in terms of the changing contributions of radiation and conduction with temperature and composition dependence of the absorption coefficient. Based on the obtained thermal conductivities, a simple model for a waste glass melter was set up, which was used to analyze the relative contributions of conduction and radiation individually and collectively to the overall heat flow and to investigate factors and conditions that influence the radiation contribution to heat flow. The modeling results showed that unlike the case at lower temperatures, the radiant energy flow through waste melts could be predominant compared with conduction at temperature of about 900 °C or higher. However, heat flow due to radiation was roughly equal to that from

  16. Finite-thrust optimization of interplanetary transfers of space vehicle with bimodal nuclear thermal propulsion

    NASA Astrophysics Data System (ADS)

    Kharytonov, Oleksii M.; Kiforenko, Boris M.

    2011-08-01

    The nuclear thermal rocket (NTR) propulsion is one of the leading promising technologies for primary space propulsion for manned exploration of the solar system due to its high specific impulse capability and sufficiently high thrust-to-weight ratio. Another benefit of NTR is its possible bimodal design, when nuclear reactor is used for generation of a jet thrust in a high-thrust mode and (with an appropriate power conversion system) as a source of electric power to supply the payload and the electric engines in a low-thrust mode. The model of the NTR thrust control was developed considering high-thrust NTR as a propulsion system of limited power and exhaust velocity. For the proposed model the control of the thrust value is accomplished by the regulation of reactor thermal power and propellant mass flow rate. The problem of joint optimization of the combination of high- and low-thrust arcs and the parameters of bimodal NTR (BNTR) propulsion system is considered for the interplanetary transfers. The interplanetary trajectory of the space vehicle is formed by the high-thrust NTR burns, which define planet-centric maneuvers and by the low-thrust heliocentric arcs where the nuclear electric propulsion (NEP) is used. The high-thrust arcs are analyzed using finite-thrust approach. The motion of the corresponding dynamical system is realized in three phase spaces concerning the departure planet-centric maneuver by means of high-thrust NTR propulsion, the low-thrust NEP heliocentric maneuver and the approach high-thrust NTR planet-centric maneuver. The phase coordinates are related at the time instants of the change of the phase spaces due to the relations between the space vehicle masses. The optimal control analysis is performed using Pontryagin's maximum principle. The numerical results are analyzed for Earth-Mars "sprint" transfer. The optimal values of the parameters that define the masses of NTR and NEP subsystems have been evaluated. It is shown that the low

  17. Epistemological considerations in the extrapolation of metabolic data from non-humans to humans. [Validity of interspecies extrapolation

    SciTech Connect

    Crawford, D.J.; Richmond, C.R.

    1980-01-01

    The rationale underlying interspecies extrapolation of metabolic data has been based primarily on pragmatic concerns. Little attention has been given to the extent to which such extrapolations have a firm epistemological basis. The strength of this approach for model-free (purely empirical) extrapolation and for extrapolation involving a variety of theoretical constructs is examined in this paper. An attempt is made to provide some understanding of the degree of confidence that can be placed in the extrapolation of metabolic data from one species to another. Published results for a wide variety of radionuclides are analyzed and the importance of these results to the field of nuclear medicine is explored. Problems inherent in the logic of extrapolation are then delineated in view of these historical data.

  18. Inter-species interconnections in acid mine drainage microbial communities

    PubMed Central

    Comolli, Luis R.; Banfield, Jill F.

    2014-01-01

    Metagenomic studies are revolutionizing our understanding of microbes in the biosphere. They have uncovered numerous proteins of unknown function in tens of essentially unstudied lineages that lack cultivated representatives. Notably, few of these microorganisms have been visualized, and even fewer have been described ultra-structurally in their essentially intact, physiologically relevant states. Here, we present cryogenic transmission electron microscope (cryo-TEM) 2D images and 3D tomographic datasets for archaeal species from natural acid mine drainage (AMD) microbial communities. Ultrastructural findings indicate the importance of microbial interconnectedness via a range of mechanisms, including direct cytoplasmic bridges and pervasive pili. The data also suggest a variety of biological structures associated with cell-cell interfaces that lack explanation. Some may play roles in inter-species interactions. Interdependences amongst the archaea may have confounded prior isolation efforts. Overall, the findings underline knowledge gaps related to archaeal cell components and highlight the likely importance of co-evolution in shaping microbial lineages. PMID:25120533

  19. Interspecies tunneling in one-dimensional Bose mixtures

    SciTech Connect

    Pflanzer, Anika C.; Zoellner, Sascha; Schmelcher, Peter

    2010-02-15

    We study the ground-state properties and quantum dynamics of few-boson mixtures with strong interspecies repulsion in one-dimensional traps. If one species localizes at the center, e.g., due to a very large mass compared to the other component, it represents an effective barrier for the latter, and the system can be mapped onto identical bosons in a double well. For weaker localization, the barrier atoms begin to respond to the light component, leading to an induced attraction between the mobile atoms that may even outweigh their bare intraspecies repulsion. To explain the resulting effects, we derive an effective Hubbard model for the lighter species accounting for the back action of the barrier in correction terms to the lattice parameters. Also the tunneling is drastically affected: by varying the degree of localization of the 'barrier' atoms, the dynamics of intrinsically noninteracting bosons can change from Rabi oscillations to effective pair tunneling. For identical fermions (or fermionized bosons), this leads to the tunneling of attractively bound pairs.

  20. Analysis of copy number variation using quantitative interspecies competitive PCR.

    PubMed

    Williams, Nigel M; Williams, Hywel; Majounie, Elisa; Norton, Nadine; Glaser, Beate; Morris, Huw R; Owen, Michael J; O'Donovan, Michael C

    2008-10-01

    Over recent years small submicroscopic DNA copy-number variants (CNVs) have been highlighted as an important source of variation in the human genome, human phenotypic diversity and disease susceptibility. Consequently, there is a pressing need for the development of methods that allow the efficient, accurate and cheap measurement of genomic copy number polymorphisms in clinical cohorts. We have developed a simple competitive PCR based method to determine DNA copy number which uses the entire genome of a single chimpanzee as a competitor thus eliminating the requirement for competitive sequences to be synthesized for each assay. This results in the requirement for only a single reference sample for all assays and dramatically increases the potential for large numbers of loci to be analysed in multiplex. In this study we establish proof of concept by accurately detecting previously characterized mutations at the PARK2 locus and then demonstrating the potential of quantitative interspecies competitive PCR (qicPCR) to accurately genotype CNVs in association studies by analysing chromosome 22q11 deletions in a sample of previously characterized patients and normal controls. PMID:18697816

  1. PRIMATES AND PRIMATOLOGISTS: SOCIAL CONTEXTS FOR INTERSPECIES PATHOGEN TRANSMISSION

    PubMed Central

    Engel, GA; Jones-Engel, L

    2011-01-01

    Humans and nonhuman primates (NHP) interact in a variety of contexts. The frequency, duration and intensity of interspecies interaction influence the likelihood that contact results in cross-species transmission of infectious agents. Here we present results of a cross-sectional survey of attendees at a national conference of primatologists, characterizing their occupational exposures to NHP. Of 116 individuals who participated in the study, 68.1% reported having worked with NHP in a field setting, 68.1% in a laboratory setting and 24.1% at a zoo or animal sanctuary. Most subjects (N=98, 84.5%) reported having worked with multiple NHP taxa, including 46 (39.7%) who had worked with more than 5 distinct taxa. Sixty-nine subjects (59.5%) recalled having been scratched by a NHP and 48 (41.1%) had been bitten; 32 subjects reporting being bitten more than once. Eleven subjects (9.5%) reported having been injured by a needle containing NHP tissue or body fluids. We conclude that primatologists are at high risk for exposure to NHP-borne infectious agents. Furthermore, primatologists’ varied occupational activities often bring them into contact with multiple NHP species in diverse contexts and geographic areas, over extended periods of time, making them a unique population with respect to zoonotic and anthropozoonotic disease risk. PMID:21932331

  2. Interspecies Interaction between Pseudomonas aeruginosa and Other Microorganisms

    PubMed Central

    Tashiro, Yosuke; Yawata, Yutaka; Toyofuku, Masanori; Uchiyama, Hiroo; Nomura, Nobuhiko

    2013-01-01

    Microbes interact with each other in multicellular communities and this interaction enables certain microorganisms to survive in various environments. Pseudomonas aeruginosa is a highly adaptable bacterium that ubiquitously inhabits diverse environments including soil, marine habitats, plants and animals. Behind this adaptivity, P. aeruginosa has abilities not only to outcompete others but also to communicate with each other to develop a multispecies community. In this review, we focus on how P. aeruginosa interacts with other microorganisms. P. aeruginosa secretes antimicrobial chemicals to compete and signal molecules to cooperate with other organisms. In other cases, it directly conveys antimicrobial enzymes to other bacteria using the Type VI secretion system (T6SS) or membrane vesicles (MVs). Quorum sensing is a central regulatory system used to exert their ability including antimicrobial effects and cooperation with other microbes. At least three quorum sensing systems are found in P. aeruginosa, Las, Rhl and Pseudomonas quinolone signal (PQS) systems. These quorum-sensing systems control the synthesis of extracellular antimicrobial chemicals as well as interaction with other organisms via T6SS or MVs. In addition, we explain the potential of microbial interaction analysis using several micro devices, which would bring fresh sensitivity to the study of interspecies interaction between P. aeruginosa and other organisms. PMID:23363620

  3. Coupled quantum-classical method for long range charge transfer: relevance of the nuclear motion to the quantum electron dynamics

    NASA Astrophysics Data System (ADS)

    da Silva, Robson; Hoff, Diego A.; Rego, Luis G. C.

    2015-04-01

    Charge and excitonic-energy transfer phenomena are fundamental for energy conversion in solar cells as well as artificial photosynthesis. Currently, much interest is being paid to light-harvesting and energy transduction processes in supramolecular structures, where nuclear dynamics has a major influence on electronic quantum dynamics. For this reason, the simulation of long range electron transfer in supramolecular structures, under environmental conditions described within an atomistic framework, has been a difficult problem to study. This work describes a coupled quantum mechanics/molecular mechanics method that aims at describing long range charge transfer processes in supramolecular systems, taking into account the atomistic details of large molecular structures, the underlying nuclear motion, and environmental effects. The method is applied to investigate the relevance of electron-nuclei interaction on the mechanisms for photo-induced electron-hole pair separation in dye-sensitized interfaces as well as electronic dynamics in molecular structures.

  4. Production of transgenic dairy goat expressing human α-lactalbumin by somatic cell nuclear transfer.

    PubMed

    Feng, Xiujing; Cao, Shaoxian; Wang, Huili; Meng, Chunhua; Li, Jingxin; Jiang, Jin; Qian, Yong; Su, Lei; He, Qiang; Zhang, Qingxiao

    2015-02-01

    Production of human α-lactalbumin (hα-LA) transgenic cloned dairy goats has great potential in improving the nutritional value and perhaps increasing the yield of dairy goat milk. Here, a mammary-specific expression vector 5A, harboring goat β-lactoglobulin (βLG) promoter, the hα-LA gene, neo(r) and EGFP dual markers, was constructed. Then, it was effectively transfected into goat mammary epithelial cells (GMECs) and the expression of hα-LA was investigated. Both the hα-LA transcript and protein were detected in the transfected GMECs after the induction of hormonal signals. In addition, the 5A vector was introduced into dairy goat fetal fibroblasts (transfection efficiency ≈60-70%) to prepare competent transgenic donor cells. A total of 121 transgenic fibroblast clones were isolated by 96-well cell culture plates and screened with nested-PCR amplification and EGFP fluorescence. After being frozen for 8 months, the transgenic cells still showed high viabilities, verifying their ability as donor cells. Dairy goat cloned embryos were produced from these hα-LA transgenic donor cells by somatic cell nuclear transfer (SCNT), and the rates of fusion, cleavage, and the development to blastocyst stages were 81.8, 84.4, and 20.0%, respectively. A total of 726 reconstructed embryos derived from the transgenic cells were transferred to 74 recipients and pregnancy was confirmed at 90 days in 12 goats. Of six female kids born, two carried hα-LA and the hα-LA protein was detected in their milk. This study provides an effective system to prepare SCNT donor cells and transgenic animals for human recombinant proteins. PMID:25139669

  5. Effects of Histone Deacetylase Inhibitor Oxamflatin on In Vitro Porcine Somatic Cell Nuclear Transfer Embryos

    PubMed Central

    Hou, Liming; Ma, Fanhua; Yang, Jinzeng; Riaz, Hasan; Wang, Yongliang; Wu, Wangjun; Xia, Xiaoliang; Ma, Zhiyuan; Zhou, Ying; Zhang, Lin; Ying, Wenqin; Xu, Dequan; Zuo, Bo; Ren, Zhuqing

    2014-01-01

    Abstract Low cloning efficiency is considered to be caused by the incomplete or aberrant epigenetic reprogramming of differentiated donor cells in somatic cell nuclear transfer (SCNT) embryos. Oxamflatin, a novel class of histone deacetylase inhibitor (HDACi), has been found to improve the in vitro and full-term developmental potential of SCNT embryos. In the present study, we studied the effects of oxamflatin treatment on in vitro porcine SCNT embryos. Our results indicated that the rate of in vitro blastocyst formation of SCNT embryos treated with 1 μM oxamflatin for 15 h postactivation was significantly higher than all other treatments. Treatment of oxamflatin decreased the relative histone deacetylase (HDAC) activity in cloned embryos and resulted in hyperacetylation levels of histone H3 at lysine 9 (AcH3K9) and histone H4 at lysine 5 (AcH4K5) at pronuclear, two-cell, and four-cell stages partly through downregulating HDAC1. The suppression of HDAC6 through oxamflatin increased the nonhistone acetylation level of α-tubulin during the mitotic cell cycle of early SCNT embryos. In addition, we demonstrated that oxamflatin downregulated DNA methyltransferase 1 (DNMT1) expression and global DNA methylation level (5-methylcytosine) in two-cell-stage porcine SCNT embryos. The pluripotency-related gene POU5F1 was found to be upregulated in the oxamflatin-treated group with a decreased DNA methylation tendency in its promoter regions. Treatment of oxamflatin did not change the locus-specific DNA methylation levels of Sus scrofa heterochromatic satellite DNA sequences at the blastocyst stage. Meanwhile, our findings suggest that treatment with HDACi may contribute to maintaining the stable status of cytoskeleton-associated elements, such as acetylated α-tubulin, which may be the crucial determinants of donor nuclear reprogramming in early SCNT embryos. In summary, oxamflatin treatment improves the developmental potential of porcine SCNT embryos in vitro. PMID

  6. Lymphoid lineage differentiation potential of mouse nuclear transfer embryonic stem cells.

    PubMed

    Eslami-Arshaghi, Tarlan; Salehi, Mohammad; Soleimani, Masoud; Gholipourmalekabadi, Mazaher; Mossahebi-Mohammadi, Majid; Ardeshirylajimi, Abdolreza; Rajabi, Hoda

    2015-09-01

    Stem cells therapy is considered as an efficient strategy for the treatment of some diseases. Nevertheless, some obstacles such as probability of rejection by the immune system limit applications of this strategy. Therefore, several efforts have been made to overcome this among which using the induced pluripotent stem cells (iPSCs) and nuclear transfer embryonic stem cell (nt-ESCs) are the most efficient strategies. The objective of this study was to evaluate the differentiation potential of the nt-ESCs to lymphoid lineage in the presence of IL-7, IL-3, FLT3-ligand and TPO growth factors in vitro. To this end, the nt-ESCs cells were prepared and treated with aforementioned growth factors for 7 and 14 days. Then, the cells were examined for expression of lymphoid markers (CD3, CD25, CD127 and CD19) by quantitative PCR (q-PCR) and flow cytometry. An increased expression of CD19 and CD25 markers was observed in the treated cells compared with the negative control samples by day 7. After 14 days, the expression level of all the tested CD markers significantly increased in the treated groups in comparison with the control. The current study reveals the potential of the nt-ESCs in differentiation to lymphoid lineage in the presence of defined growth factors. PMID:26239678

  7. TEMP: A finite line heat transfer code for geologic repositories for nuclear waste

    SciTech Connect

    Wurm, K.J.; Bloom, S.G.; Atterbury, W.G.; Hetteberg, J.R.

    1987-10-01

    TEMP is a FORTRAN computer code for calculating temperatures in a geologic repository for nuclear waste. It will calculate the incremental temperature contributed by a single heat source, by an infinite array of heat sources, or by heat sources geometrically arranged in a finite array. In the finite array geometry, different types of heat sources can be placed in different regions at different times to more closely approximate the emplacement of waste in a repository. TEMP uses a semi-analytical technique for solving the equation for a heat producing finite length line source in an infinite and isotropic medium. Temperature contributions from individual heat sources are superimposed to determine the temperature at a specific location and time in a repository of multiple heat sources. Thermal conductivity of the geologic medium can be a function of temperature, and, when it is, an approximation is made for the temperature dependence of thermal diffusivity. This report derives the equations solved by TEMP and documents its accuracy by comparing its results to known analytical solutions and to the finite-difference and finite-element heat transfer codes HEATING5, HEATING6, THAC-SIP-3D, SPECTROM-41, and STEALTH-2D. The temperature results from TEMP are shown to be very accurate when compared to the analytical solutions and to the results from the finite-difference and finite-element codes. 8 refs., 97 figs., 39 tabs.

  8. Functional enucleation of porcine oocytes for somatic cell nuclear transfer using femtosecond laser pulses

    NASA Astrophysics Data System (ADS)

    Kuetemeyer, K.; Lucas-Hahn, A.; Petersen, B.; Hassel, P.; Lemme, E.; Niemann, H.; Heisterkamp, A.

    2010-02-01

    Cloning of several mammalian species has been achieved by somatic cell nuclear transfer over the last decade. However, this method still results in very low efficiencies originating from biological and technical aspects. The highly-invasive mechanical enucleation belongs to the technical aspects and requires considerable micromanipulation skill. In this paper, we present a novel non-invasive method for combined oocyte imaging and automated functional enucleation using femtosecond (fs) laser pulses. After three-dimensional imaging of Hoechst-labeled porcine oocytes by multiphoton microscopy, our self-developed software automatically determined the metaphase plate position and shape. Subsequent irradiation of this volume with the very same laser at higher pulse energies in the low-density-plasma regime was used for metaphase plate ablation. We show that functional fs laser-based enucleation of porcine oocytes completely inhibited further embryonic development while maintaining intact oocyte morphology. In contrast, non-irradiated oocytes were able to develop to the blastocyst stage without significant differences to control oocytes. Our results indicate that fs laser systems offer great potential for oocyte imaging and enucleation as a fast, easy to use and reliable tool which may improve the efficiency of somatic cell clone production.

  9. The ability of mouse nuclear transfer embryonic stem cells to differentiate into primordial germ cells

    PubMed Central

    Mansouri, Vahid; Salehi, Mohammad; Nourozian, Mohsen; Fadaei, Fatemeh; Farahani, Reza Mastery; Piryaei, Abbas; Delbari, Ali

    2015-01-01

    Nuclear transfer embryonic stem cells (ntESCs) show stem cell characteristics such as pluripotency but cause no immunological disorders. Although ntESCs are able to differentiate into somatic cells, the ability of ntESCs to differentiate into primordial germ cells (PGCs) has not been examined. In this work, we examined the capacity of mouse ntESCs to differentiate into PGCs in vitro. ntESCs aggregated to form embryoid bodies (EB) in EB culture medium supplemented with bone morphogenetic protein 4(BMP4) as the differentiation factor. The expression level of specific PGC genes was compared at days 4 and 8 using real time PCR. Flow cytometry and immunocytochemical staining were used to detect Mvh as a specific PGC marker. ntESCs expressed particular genes related to different stages of PGC development. Flow cytometry and immunocytochemical staining confirmed the presence of Mvh protein in a small number of cells. There were significant differences between cells that differentiated into PGCs in the group treated with Bmp4 compared to non-treated cells. These findings indicate that ntESCs can differentiate into putative PGCs. Improvement of ntESC differentiation into PGCs may be a reliable means of producing mature germ cells. PMID:26273226

  10. Abnormal dynamic changes in β-tubulin in somatic nuclear transfer cloned mouse embryos.

    PubMed

    Shen, Jingling; Wang, Zhendong; Shen, Xinghui; Zheng, Zhong; Zhang, Qinghua; Feng, Xiuqing; Hu, Lili; Lei, Lei

    2015-02-01

    The efficiency of somatic cell nuclear transfer (SCNT) cloning remains low, thus limiting the applications of this technique. In this study, we used immunochemistry and confocal microscopy to detect the microtubule component, β-tubulin, in SCNT, parthenogenetic (PA), and intracytoplasmic sperm injection (ICSI) embryos before the first mitotic division. β-Tubulin is the component subunit of microtubule, which plays critical roles in regulating localization of cellular organelles, and the growth, maturation and fertilization of oocytes. Our results demonstrated similar changes of spindle patterns in PA and ICSI embryos. The second meiotic division resumed 1 h post-treatment, and the cytoplasmic asters (CAs) disappeared. After about 4-6 h of treatment, pronuclei formed with the midbodies connecting each other. Meanwhile, the CAs reappeared and a microtubule network developed in the cytoplasm. However, SCNT embryos showed abnormal multipolar spindles, and the pseudopronuclei that contained many nucleoli existed after 6 h of SrCl2 activation. Enucleated oocytes alone did not form spindle-like structures when they were artificially activated for 6 h, indicating that somatic cell chromosomes might be necessary for spindle formation in SCNT embryos. These results demonstrated abnormal changes of β-tubulin in mouse SCNT embryos, compared with PA and ICSI embryos. PMID:24345634

  11. Establishment, differentiation, electroporation, viral transduction, and nuclear transfer of bovine and porcine mesenchymal stem cells.

    PubMed

    Colleoni, S; Donofrio, G; Lagutina, I; Duchi, R; Galli, C; Lazzari, G

    2005-01-01

    Mesenchymal stem cells (MSCs) reside in the bone marrow and have the potential for multilineage differentiation, into bone, cartilage, and fat, for example. In this study, bovine and porcine MSCs were isolated, cultured to determine their replication ability, and differentiated with osteogenic medium and 5-azacytine. Both bovine and porcine undifferentiated MSCs were electroporated and virally transduced to test the efficiency of genetic modification and the maintainance of differentiation ability thereafter. Nuclear transfer experiments were carried out with bovine and porcine MSCs, both at the undifferentiated state and following differentiation. Our results indicate that bovine and porcine MSCs have limited lifespans in vitro--approximately 50 population doublings. They can be efficiently differentiated and characterized along the osteogenic lineage by morphology, alkaline phosphatase, Von Kossa, oil red stainings, and RT-PCR. Electroporation and selection induce high levels of EGFP expression in porcine but not in bovine MSCs. Following genetic modification, MSCs retain their pluridifferentiation ability as parental cells. Cloned embryos derived from bovine and porcine undifferentiated MSCs and their derivatives along the osteogenic lineage give rise to consistently high preimplantation development comparable to adult fibroblasts. PMID:16176125

  12. Transcriptomic Features of Bovine Blastocysts Derived by Somatic Cell Nuclear Transfer

    PubMed Central

    Min, Byungkuk; Cho, Sunwha; Park, Jung Sun; Lee, Yun-Gyeong; Kim, Namshin; Kang, Yong-Kook

    2015-01-01

    Reprogramming incompletely occurs in most somatic cell nuclear transfer (SCNT) embryos, which results in misregulation of developmentally important genes and subsequent embryonic malfunction and lethality. Here we examined transcriptome profiles in single bovine blastocysts derived by in vitro fertilization (IVF) and SCNT. Different types of donor cells, cumulus cell and ear-skin fibroblast, were used to derive cSCNT and fSCNT blastocysts, respectively. SCNT blastocysts expressed 13,606 genes on average, similar to IVF (13,542). Correlation analysis found that both cSCNT and fSCNT blastocyst groups had transcriptomic features distinctive from the IVF group, with the cSCNT transcriptomes closer to the IVF ones than the fSCNT. Gene expression analysis identified 56 underrepresented and 78 overrepresented differentially expressed genes in both SCNT groups. A 400-kb locus harboring zinc-finger protein family genes in chromosome 18 were found coordinately down-regulated in fSCNT blastocysts, showing a feature of reprogramming-resistant regions. Probing into different categories of genes important for blastocyst development revealed that genes involved in trophectoderm development frequently were underrepresented, and those encoding epigenetic modifiers tended to be overrepresented in SCNT blastocysts. Our effort to identify reprogramming-resistant, differentially expressed genes can help map reprogramming error-prone loci onto the genome and elucidate how to handle the stochastic events of reprogramming to improve cloning efficiency. PMID:26342001

  13. Production of myostatin-targeted goat by nuclear transfer from cultured adult somatic cells.

    PubMed

    Zhou, Zheng-Rong; Zhong, Bu-Shuai; Jia, Ruo-Xin; Wan, Yong-Jie; Zhang, Yan-Li; Fan, Yi-Xuan; Wang, Li-Zhong; You, Ji-Hao; Wang, Zi-Yu; Wang, Feng

    2013-01-15

    Myostatin, a member of the transforming growth factor-β family, acts as a negative regulator of skeletal muscle mass. In this study, myostatin-targeted caprine fibroblasts were obtained and subjected to SCNT to determine whether myostatin-knockout goats could be created. Fibroblasts from a 2-mo-old goat were transfected with a myostatin-targeted vector to prepare transgenic donor cells for nuclear transfer. After serum-starvation (for synchronization of the cell cycle), the percentage of transgenic fibroblasts in the G(0)/G(1) phase increased (66.2% vs. 82.9%; P < 0.05) compared with that in the control group, whereas the apoptosis rate and mitochondrial membrane potential were unaffected (P > 0.05). There were no significant differences between in vivo- and in vitro-matured oocytes as recipient cytoplasts for rates of fusion (86.5% vs. 78.4%), pregnancy (21.6% vs. 16.7%), or kidding (2.7% vs. 0%). One female kid from an in vivo-matured oocyte was born, but died a few hours later. Microsatellite analysis and polymerase chain reaction identification confirmed that this kid was genetically identical to the donor cells. Based on Western blot analysis, myostatin of the cloned kid was not expressed compared with that of nontransgenic kids. In conclusion, SCNT using myostatin-targeted 2-mo-old goat fibroblasts as donors has potential as a method for producing myostatin-targeted goats. PMID:23174778

  14. Transcriptomic Features of Bovine Blastocysts Derived by Somatic Cell Nuclear Transfer.

    PubMed

    Min, Byungkuk; Cho, Sunwha; Park, Jung Sun; Lee, Yun-Gyeong; Kim, Namshin; Kang, Yong-Kook

    2015-12-01

    Reprogramming incompletely occurs in most somatic cell nuclear transfer (SCNT) embryos, which results in misregulation of developmentally important genes and subsequent embryonic malfunction and lethality. Here we examined transcriptome profiles in single bovine blastocysts derived by in vitro fertilization (IVF) and SCNT. Different types of donor cells, cumulus cell and ear-skin fibroblast, were used to derive cSCNT and fSCNT blastocysts, respectively. SCNT blastocysts expressed 13,606 genes on average, similar to IVF (13,542). Correlation analysis found that both cSCNT and fSCNT blastocyst groups had transcriptomic features distinctive from the IVF group, with the cSCNT transcriptomes closer to the IVF ones than the fSCNT. Gene expression analysis identified 56 underrepresented and 78 overrepresented differentially expressed genes in both SCNT groups. A 400-kb locus harboring zinc-finger protein family genes in chromosome 18 were found coordinately down-regulated in fSCNT blastocysts, showing a feature of reprogramming-resistant regions. Probing into different categories of genes important for blastocyst development revealed that genes involved in trophectoderm development frequently were underrepresented, and those encoding epigenetic modifiers tended to be overrepresented in SCNT blastocysts. Our effort to identify reprogramming-resistant, differentially expressed genes can help map reprogramming error-prone loci onto the genome and elucidate how to handle the stochastic events of reprogramming to improve cloning efficiency. PMID:26342001

  15. TRANSFER OF EXCESS NUCLEAR MATERIAL FROM LOS ALAMOS TO SAVANNAH RIVER SITE FOR LONG-TERM DISPOSITION

    SciTech Connect

    C. W. HOTH; L. A. FOSTER; T. F YARBRO

    2001-06-01

    Los Alamos National Laboratory is preparing excess nuclear material for shipment to Savannah River Site (SRS) for final disposition. Prior to shipment the nuclear material will be stabilized and packaged to meet strict criteria. The criterion that must be met include: (1) the DOE stabilization, packaging and storage requirements for plutonium bearing materials, DOE-STD-3013, (2) shipping container packaging requirements, (3) SRS packaging and storage criteria, and (4) DOE Material Disposition criteria for either immobilization or MOX reactor fuel. Another issue in preparing for this transfer is the DOE certification of shipping containers and the availability of shipping containers. This transfer of the nuclear material is fully supported by the EM, DP and NN Sections of the DOE, as well as, by LANL and SRS, yet a strong collaboration is needed to meet all established requirements relating to stabilization, packaging, shipment, storage and final disposition. This paper will present the overall objectives, the issues and the planned strategy to accomplish this nuclear material transfer.

  16. Operational safety enhancement of Soviet-designed nuclear reactors via development of nuclear power plant simulators and transfer of related technology

    SciTech Connect

    Kohut, P.; Epel, L.G.; Tutu, N.K.

    1998-08-01

    The US Department of Energy (DOE), under the US government`s International Nuclear Safety Program (INSP), is implementing a program of developing and providing simulators for many of the Russian and Ukrainian Nuclear Power Plants (NPPs). Pacific Northwest National Laboratory (PNNL) and Brookhaven National Laboratory (BNL) manage and provide technical oversight of the various INSP simulator projects for DOE. The program also includes a simulator technology transfer process to simulator design organizations in Russia and Ukraine. Training programs, installation of new simulators, and enhancements in existing simulators are viewed as providing a relatively fast and cost-effective technology transfer that will result in measurable improvement in the safety culture and operation of NPPs. A review of this program, its present status, and its accomplishments are provided in this paper.

  17. Inter-species entanglement of Bose–Bose mixtures trapped in optical lattices

    NASA Astrophysics Data System (ADS)

    (王 巍, Wei Wang; Penna, Vittorio; Capogrosso-Sansone, Barbara

    2016-06-01

    In the present work we discuss inter-species entanglement in Bose–Bose mixtures trapped in optical lattices. This work is motivated by the observation that, in the presence of a second component, the MI lobe shifts differently on the hole- and particle-side with respect to the Mott lobe of the single species system (Guglielmino et al 2010 Phys. Rev. A 82 021601; Capogrosso-Sansone et al 2011 Laser Phys. 21 1443). We use perturbation theory, formulated in a Hilbert space decomposed by means of lattice symmetries, in order to show that the nonuniform shift of the Mott lobe is a manifestation of inter-species entanglement which differs in the lowest excited states to remove and add a particle. Our results indicate that inter-species entanglement in mixtures can provide a new perspective in understanding quantum phase transitions. To validate our approach, we compare our results from perturbation theory with quantum Monte Carlo simulations.

  18. Nuclear transfer of synchronized african wild cat somatic cells into enucleated domestic cat oocytes.

    PubMed

    Gómez, Martha C; Jenkins, Jill A; Giraldo, Angelica; Harris, Rebecca F; King, Amy; Dresser, Betsy L; Pope, Charles Earle

    2003-09-01

    The African wild cat is one of the smallest wild cats and its future is threatened by hybridization with domestic cats. Nuclear transfer, a valuable tool for retaining genetic variability, offers the possibility of species continuation rather than extinction. The aim of this study was to investigate the ability of somatic cell nuclei of the African wild cat (AWC) to dedifferentiate within domestic cat (DSH) cytoplasts and to support early development after nuclear transplantation. In experiment 1, distributions of AWC and DSH fibroblasts in each cell-cycle phase were assessed by flow cytometry using cells cultured to confluency and disaggregated with pronase, trypsin, or mechanical separation. Trypsin (89.0%) and pronase (93.0%) yielded higher proportions of AWC nuclei in the G0/G1 phase than mechanical separation (82.0%). In contrast, mechanical separation yielded higher percentages of DSH nuclei in the G0/G1 phase (86.6%) than pronase (79.7%) or trypsin (74.2%) treatments. In both species, pronase induced less DNA damage than trypsin. In experiment 2, the effects of serum starvation, culture to confluency, and exposure to roscovitine on the distribution of AWC and DSH fibroblasts in various phases of the cell cycle were determined. Flow cytometry analyses revealed that the dynamics of the cell cycle varied as culture conditions were modified. Specifically, a higher percentage of AWC and DSH nuclei were in the G0/G1 phase after cells were serum starved (83% vs. 96%) than were present in cycling cells (50% vs. 64%), after contact inhibition (61% vs. 88%), or after roscovitine (56% vs. 84%) treatment, respectively. In experiment 3, we evaluated the effects of cell synchronization and oocyte maturation (in vivo vs. in vitro) on the reconstruction and development of AWC-DSH- and DSH-DSH-cloned embryos. The method of cell synchronization did not affect the fusion and cleavage rate because only a slightly higher percentage of fused couplets cleaved when donor nuclei

  19. Nuclear transfer of synchronized African wild cat somatic cells into enucleated domestic cat oocytes

    USGS Publications Warehouse

    Gomez, M.C.; Jenkins, J.A.; Giraldo, A.; Harris, R.F.; King, A.; Dresser, B.L.; Pope, C.E.

    2003-01-01

    The African wild cat is one of the smallest wild cats and its future is threatened by hybridization with domestic cats. Nuclear transfer, a valuable tool for retaining genetic variability, offers the possibility of species continuation rather than extinction. The aim of this study was to investigate the ability of somatic cell nuclei of the African wild cat (AWC) to dedifferentiate within domestic cat (DSH) cytoplasts and to support early development after nuclear transplantation. In experiment 1, distributions of AWC and DSH fibroblasts in each cell-cycle phase were assessed by flow cytometry using cells cultured to confluency and disaggregated with pronase, trypsin, or mechanical separation. Trypsin (89.0%) and pronase (93.0%) yielded higher proportions of AWC nuclei in the G0/G1 phase than mechanical separation (82.0%). In contrast, mechanical separation yielded higher percentages of DSH nuclei in the G0/G1 phase (86.6%) than pronase (79.7%) or trypsin (74.2%) treatments. In both species, pronase induced less DNA damage than trypsin. In experiment 2, the effects of serum starvation, culture to confluency, and exposure to roscovitine on the distribution of AWC and DSH fibroblasts in various phases of the cell cycle were determined. Flow cytometry analyses revealed that the dynamics of the cell cycle varied as culture conditions were modified. Specifically, a higher percentage of AWC and DSH nuclei were in the G0/G1 phase after cells were serum starved (83% vs. 96%) than were present in cycling cells (50% vs. 64%), after contact inhibition (61% vs. 88%), or after roscovitine (56% vs. 84%) treatment, respectively. In experiment 3, we evaluated the effects of cell synchronization and oocyte maturation (in vivo vs. in vitro) on the reconstruction and development of AWC-DSH- and DSH-DSH-cloned embryos. The method of cell synchronization did not affect the fusion and cleavage rate because only a slightly higher percentage of fused couplets cleaved when donor nuclei

  20. Effects of donor fibroblasts expressing OCT4 on bovine embryos generated by somatic cell nuclear transfer.

    PubMed

    Goissis, Marcelo D; Suhr, Steven T; Cibelli, Jose B

    2013-02-01

    The production of healthy, live, cloned animals by somatic cell nuclear transfer (SCNT) has been hampered by low efficiencies. Significant epigenetic changes must take place to ensure proper chromatin remodeling in SCNT. We hypothesized that exogenous expression of OCT4 in donor fibroblasts prior to its fusion with enucleated oocytes would facilitate SCNT reprogramming. We infected bovine adult fibroblasts with retroviral vectors containing yellow fluorescent protein (YFP) only, or the OCT4 gene fused to YFP (YO). We found that development to the blastocyst stage was not different between NT-YFP and NT-YO groups. NT-YFP embryos had the fewest trophoblast cells, measured by numbers of CDX2-positive cells. Fibroblasts expressing OCT4 had reduced levels of histone 3 lysine 9 or 27 trimethylation (H3K9me3 and H3K27me3, respectively). NT-YO blastocysts displayed higher H3K9me3 levels than IVF and NT-YFP embryos; however, they did not have different H3K27me3 levels. Levels of XIST mRNA expression in NT-YO and NT-YF were higher when compared to in vitro-fertilized blastocysts. We observed no differences in the expression of SOX2, NANOG, and CDX2. Although overexpression of OCT4 in donor cells increased H3K9me3 and did not reduce XIST gene expression, we show that a single transcription factor can affect the number of trophectoderm cells in bovine SCNT embryos. PMID:23276226

  1. Ovine induced pluripotent stem cells are resistant to reprogramming after nuclear transfer.

    PubMed

    German, Sergio D; Campbell, Keith H S; Thornton, Elisabeth; McLachlan, Gerry; Sweetman, Dylan; Alberio, Ramiro

    2015-02-01

    Induced pluripotent stem cells (iPSCs) share similar characteristics of indefinite in vitro growth with embryonic stem cells (ESCs) and may therefore serve as a useful tool for the targeted genetic modification of farm animals via nuclear transfer (NT). Derivation of stable ESC lines from farm animals has not been possible, therefore, it is important to determine whether iPSCs can be used as substitutes for ESCs in generating genetically modified cloned farm animals. We generated ovine iPSCs by conventional retroviral transduction using the four Yamanaka factors. These cells were basic fibroblast growth factor (bFGF)- and activin A-dependent, showed persistent expression of the transgenes, acquired chromosomal abnormalities, and failed to activate endogenous NANOG. Nonetheless, iPSCs could differentiate into the three somatic germ layers in vitro. Because cloning of farm animals is best achieved with diploid cells (G1/G0), we synchronized the iPSCs in G1 prior to NT. Despite the cell cycle synchronization, preimplantation development of iPSC-NT embryos was lower than with somatic cells (2% vs. 10% blastocysts, p<0.01). Furthermore, analysis of the blastocysts produced demonstrated persistent expression of the transgenes, aberrant expression of endogenous SOX2, and a failure to activate NANOG consistently. In contrast, gene expression in blastocysts produced with the parental fetal fibroblasts was similar to those generated by in vitro fertilization. Taken together, our data suggest that the persistent expression of the exogenous factors and the acquisition of chromosomal abnormalities are incompatible with normal development of NT embryos produced with iPSCs. PMID:25513856

  2. Vitamin C enhances in vitro and in vivo development of porcine somatic cell nuclear transfer embryos

    SciTech Connect

    Huang, Yongye; Tang, Xiaochun; Xie, Wanhua; Zhou, Yan; Li, Dong; Zhou, Yang; Zhu, Jianguo; Yuan, Ting; Lai, Liangxue; Pang, Daxin; Ouyang, Hongsheng

    2011-07-29

    Highlights: {yields} Report for the first time that vitamin C has a beneficial effect on the development of porcine SCNT embryos. {yields} The level of acH4K5 and Oct4 expression at blastocyst-stage was up-regulated after treatment. {yields} A higher rate of gestation and increased number of piglets born were harvested in the treated group. -- Abstract: The reprogramming of differentiated cells into a totipotent embryonic state through somatic cell nuclear transfer (SCNT) is still an inefficient process. Previous studies revealed that the generation of induced pluripotent stem (iPS) cells from mouse and human fibroblasts could be significantly enhanced with vitamin C treatment. Here, we investigated the effects of vitamin C, to our knowledge for the first time, on the in vitro and in vivo development of porcine SCNT embryos. The rate of blastocyst development in SCNT embryos treated with 50 {mu}g/mL vitamin C 15 h after activation (36.0%) was significantly higher than that of untreated SCNT embryos (11.5%). The enhanced in vitro development rate of vitamin C-treated embryos was associated with an increased acetylation level of histone H4 lysine 5 and higher Oct4, Sox2 and Klf4 expression levels in blastocysts, as determined by real-time PCR. In addition, treatment with vitamin C resulted in an increased pregnancy rate in pigs. These findings suggest that treatment with vitamin C is beneficial for enhancement of the in vitro and in vivo development of porcine SCNT embryos.

  3. Best Practices for Finite Element Analysis of Spent Nuclear Fuel Transfer, Storage, and Transportation Systems

    SciTech Connect

    Bajwa, Christopher S.; Piotter, Jason; Cuta, Judith M.; Adkins, Harold E.; Klymyshyn, Nicholas A.; Fort, James A.; Suffield, Sarah R.

    2010-08-11

    Storage casks and transportation packages for spent nuclear fuel (SNF) are designed to confine SNF in sealed canisters or casks, provide structural integrity during accidents, and remove decay through a storage or transportation overpack. The transfer, storage, and transportation of SNF in dry storage casks and transport packages is regulated under 10 CFR Part 72 and 10 CFR Part 71, respectively. Finite Element Analysis (FEA) is used with increasing frequency in Safety Analysis Reports and other regulatory technical evaluations related to SNF casks and packages and their associated systems. Advances in computing power have made increasingly sophisticated FEA models more feasible, and as a result, the need for careful review of such models has also increased. This paper identifies best practice recommendations that stem from recent NRC review experience. The scope covers issues common to all commercially available FEA software, and the recommendations are applicable to any FEA software package. Three specific topics are addressed: general FEA practices, issues specific to thermal analyses, and issues specific to structural analyses. General FEA practices covers appropriate documentation of the model and results, which is important for an efficient review process. The thermal analysis best practices are related to cask analysis for steady state conditions and transient scenarios. The structural analysis best practices are related to the analysis of casks and associated payload during standard handling and drop scenarios. The best practices described in this paper are intended to identify FEA modeling issues and provide insights that can help minimize associated uncertainties and errors, in order to facilitate the NRC licensing review process.

  4. Protein profiles of bovine placenta derived from somatic cell nuclear transfer.

    PubMed

    Kim, Hong Rye; Kang, Jae Ku; Yoon, Jong Taek; Seong, Hwan Hoo; Jung, Jin Kwan; Lee, Hong Mie; Sik Park, Chang; Jin, Dong Il

    2005-11-01

    Practical application of animal cloning by somatic cell nuclear transfer (SCNT) has been hampered by an extremely low success rate. To address whether placental dysfunction in SCNT causes fetal loss during pregnancy, we have used a global proteomics approach using 2-DE and MS to analyze the differential protein patterns of three placentae from the afterbirth of cases of postnatal death, derived from SCNT of Korean Native cattle, and three normal placentae obtained from the afterbirth of fetuses derived from artificial insemination. Proteins within a pI range of 4.0-7.0 and 6.0-9.0 were analyzed separately by 2-DE in triplicate. A total of approximately 2000 spots were detected in placental 2-DE gels stained with CBB. In the comparison of normal and SCNT samples, 60 spots were identified as differentially expressed proteins, of which 33 spots were up-regulated proteins in SCNT placentae, while 27 spots were down-regulated proteins. Most of the proteins identified in this analysis appeared to be related with protein repair or protection, cytoskeleton, signal transduction, immune system, metabolism, extracellular matrix and remodeling, transcription regulation, cell structure or differentiation and ion transport. One of up-regulated proteins in SCNT was TIMP-2 protein known to be related to extracellular matrix and remodeling during pregnancy. Western blot analysis showed an increased level of TIMP-2 in SCNT placenta compared to normal. Our results revealed composite profiles of key proteins involved in abnormal placenta derived from SCNT, and suggested expression abnormality of these genes in SCNT placenta, resulting in fetal losses following SCNT. PMID:16196098

  5. [Dynamic changes of γ-tubulin in mouse somatic cell nuclear transferred embryos].

    PubMed

    Zhang, Qing-Hua; Lei, Lei

    2013-04-25

    The aim of the present study is to observe the dynamic changes of γ-tubulin in mouse somatic nuclear transferred (SCNT) embryos. The γ-tubulin was detected and analyzed in the enucleated oocyte and SCNT embryos by immunofluorescence and laser confocal microscopy. The results showed that γ-tubulin distributed in the cortex of the enucleated MII oocytes, and decreased in this area during the activation of oocytes. Meanwhile cytoplasmic asters appeared, but there was no spindle formed. Spindle formation could be observed in the enucleated oocytes which were injected with cumulus cells and activated by SrCl2. The spots-like γ-tubulin signals spread between chromosomes at the prophase, and the signals arrayed with spindle or aggregated at two poles of the spindle at the early metaphase. Furthermore, γ-tubulin signals were localized between the segregated sister chromatids at anaphase or telophase. Some reconstructed embryos exhibited advanced activation, showing abnormal spindles and aberrant distribution of γ-tubulin and chromosomes. Two spindles would be formed when the cumulus cell was injected into an intact oocyte, and the distribution of γ-tubulin was similar to that of the normal SCNT. Moreover, advanced activation also occurred in this case and formed either two small spindles or one big barrel-shaped spindle. These results suggest that γ-tubulin plays a pivotal role in spindle assembling in mouse SCNT embryos. The reconstructed oocytes were easily to be activated, and aberrant distribution of γ-tubulin is associated with formation of abnormal spindles and chromosome misalignment. PMID:23598871

  6. Improving the development of early bovine somatic-cell nuclear transfer embryos by treating adult donor cells with vitamin C.

    PubMed

    Chen, Huanhuan; Zhang, Lei; Guo, Zekun; Wang, Yongsheng; He, Rongjun; Qin, Yumin; Quan, Fusheng; Zhang, Yong

    2015-11-01

    Vitamin C (Vc) has been widely studied in cell and embryo culture, and has recently been demonstrated to promote cellular reprogramming. The objective of this study was to identify a suitable Vc concentration that, when used to treat adult bovine fibroblasts serving as donor cells for nuclear transfer, improved donor-cell physiology and the developmental potential of the cloned embryos that the donor nuclei were used to create. A Vc concentration of 0.15 mM promoted cell proliferation and increased donor-cell 5-hydroxy methyl cytosine levels 2.73-fold (P < 0.05). The blastocyst rate was also significantly improved after nuclear transfer (39.6% treated vs. 26.0% control, P < 0.05); the average number of apoptotic cells in cloned blastocysts was significantly reduced (2.2 vs. 4.4, P < 0.05); and the inner cell mass-to-trophectoderm ratio (38.25% vs. 30.75%, P < 0.05) and expression of SOX2 (3.71-fold, P < 0.05) and POU5F1 (3.15-fold, P < 0.05) were significantly increased. These results suggested that Vc promotes cell proliferation, decreases DNA methylation levels in donor cells, and improves the developmental competence of bovine somatic-cell nuclear transfer embryos. PMID:26212732

  7. Frequent somatic transfer of mitochondrial DNA into the nuclear genome of human cancer cells.

    PubMed

    Ju, Young Seok; Tubio, Jose M C; Mifsud, William; Fu, Beiyuan; Davies, Helen R; Ramakrishna, Manasa; Li, Yilong; Yates, Lucy; Gundem, Gunes; Tarpey, Patrick S; Behjati, Sam; Papaemmanuil, Elli; Martin, Sancha; Fullam, Anthony; Gerstung, Moritz; Nangalia, Jyoti; Green, Anthony R; Caldas, Carlos; Borg, Åke; Tutt, Andrew; Lee, Ming Ta Michael; van't Veer, Laura J; Tan, Benita K T; Aparicio, Samuel; Span, Paul N; Martens, John W M; Knappskog, Stian; Vincent-Salomon, Anne; Børresen-Dale, Anne-Lise; Eyfjörd, Jórunn Erla; Flanagan, Adrienne M; Foster, Christopher; Neal, David E; Cooper, Colin; Eeles, Rosalind; Lakhani, Sunil R; Desmedt, Christine; Thomas, Gilles; Richardson, Andrea L; Purdie, Colin A; Thompson, Alastair M; McDermott, Ultan; Yang, Fengtang; Nik-Zainal, Serena; Campbell, Peter J; Stratton, Michael R

    2015-06-01

    Mitochondrial genomes are separated from the nuclear genome for most of the cell cycle by the nuclear double membrane, intervening cytoplasm, and the mitochondrial double membrane. Despite these physical barriers, we show that somatically acquired mitochondrial-nuclear genome fusion sequences are present in cancer cells. Most occur in conjunction with intranuclear genomic rearrangements, and the features of the fusion fragments indicate that nonhomologous end joining and/or replication-dependent DNA double-strand break repair are the dominant mechanisms involved. Remarkably, mitochondrial-nuclear genome fusions occur at a similar rate per base pair of DNA as interchromosomal nuclear rearrangements, indicating the presence of a high frequency of contact between mitochondrial and nuclear DNA in some somatic cells. Transmission of mitochondrial DNA to the nuclear genome occurs in neoplastically transformed cells, but we do not exclude the possibility that some mitochondrial-nuclear DNA fusions observed in cancer occurred years earlier in normal somatic cells. PMID:25963125

  8. Frequent somatic transfer of mitochondrial DNA into the nuclear genome of human cancer cells

    PubMed Central

    Ju, Young Seok; Tubio, Jose M.C.; Mifsud, William; Fu, Beiyuan; Davies, Helen R.; Ramakrishna, Manasa; Li, Yilong; Yates, Lucy; Gundem, Gunes; Tarpey, Patrick S.; Behjati, Sam; Papaemmanuil, Elli; Martin, Sancha; Fullam, Anthony; Gerstung, Moritz; Nangalia, Jyoti; Green, Anthony R.; Caldas, Carlos; Borg, Åke; Tutt, Andrew; Lee, Ming Ta Michael; van't Veer, Laura J.; Tan, Benita K.T.; Aparicio, Samuel; Span, Paul N.; Martens, John W.M.; Knappskog, Stian; Vincent-Salomon, Anne; Børresen-Dale, Anne-Lise; Eyfjörd, Jórunn Erla; Flanagan, Adrienne M.; Foster, Christopher; Neal, David E.; Cooper, Colin; Eeles, Rosalind; Lakhani, Sunil R.; Desmedt, Christine; Thomas, Gilles; Richardson, Andrea L.; Purdie, Colin A.; Thompson, Alastair M.; McDermott, Ultan; Yang, Fengtang; Nik-Zainal, Serena; Campbell, Peter J.; Stratton, Michael R.

    2015-01-01

    Mitochondrial genomes are separated from the nuclear genome for most of the cell cycle by the nuclear double membrane, intervening cytoplasm, and the mitochondrial double membrane. Despite these physical barriers, we show that somatically acquired mitochondrial-nuclear genome fusion sequences are present in cancer cells. Most occur in conjunction with intranuclear genomic rearrangements, and the features of the fusion fragments indicate that nonhomologous end joining and/or replication-dependent DNA double-strand break repair are the dominant mechanisms involved. Remarkably, mitochondrial-nuclear genome fusions occur at a similar rate per base pair of DNA as interchromosomal nuclear rearrangements, indicating the presence of a high frequency of contact between mitochondrial and nuclear DNA in some somatic cells. Transmission of mitochondrial DNA to the nuclear genome occurs in neoplastically transformed cells, but we do not exclude the possibility that some mitochondrial-nuclear DNA fusions observed in cancer occurred years earlier in normal somatic cells. PMID:25963125

  9. Comparison of microinjection (piezo-electric) and cell fusion for nuclear transfer success with different cell types in cattle.

    PubMed

    Galli, Cesare; Lagutina, Irina; Vassiliev, Ivan; Duchi, Roberto; Lazzari, Giovanna

    2002-01-01

    Amongst the many variables that can determine success of cloning, the source of nuclei, the procedure used for nuclear transfer, and the activation of the reconstructed embryo are very important aspects. In this study, we have compared the two most common procedures for transferring nuclei to enucleated oocytes--cell fusion (CF) and piezoelectric microinjection (PEM) using different somatic cells--and we have investigated the effect of different activation procedures. Granulosa cells and fibroblasts were grown to confluency or in low serum to induce a quiescent state, while lymphocytes were thawed immediately prior to use. Enucleated oocytes were reconstructed either with CF or PME by 21-23 h postmaturation. For cell fusion, one pulse of 1 kVolt/cm for 30 microsec was used; for PEM, the cell membrane was broken by repeated pipetting and transferred in a 12% PVP solution to facilitate injection. Manipulated oocytes were activated with ionomycin and cycloheximide (CHX) or 6-DMAP (DMAP) and cultured in microdrops of SOF-BSA-AA. On day 7 (day 0: nuclear transfer), embryo development was evaluated and embryos were either transferred fresh or were frozen. More embryos were successfully reconstructed with PEM than CF, but a higher number of reconstructed embryos by CF developed to blastocyst at D + 7. In addition, in both systems more embryos were obtained after activation with DMAP than with CHX. The transfer of 141 embryos to recipients resulted in a pregnancy rate of 50%, and no differences were observed between the source of donor cell, the reconstruction methods, or the activation protocol. Six calves were delivered at term, and four survived. High pregnancy losses were observed throughout the gestation period. PMID:12398800

  10. The Arabidopsis repressor of light signaling, COP1, is regulated by nuclear exclusion: Mutational analysis by bioluminescence resonance energy transfer

    PubMed Central

    Subramanian, Chitra; Kim, Byung-Hoon; Lyssenko, Nicholas N.; Xu, Xiaodong; Johnson, Carl Hirschie; von Arnim, Albrecht G.

    2004-01-01

    Bioluminescence resonance energy transfer (BRET) between Renilla luciferase and yellow fluorescent protein has been adapted to serve as a real-time reporter on protein-protein interactions in live plant cells by using the Arabidopsis Constitutive photomorphogenesis 1 (COP1) protein as a model system. COP1 is a repressor of light signal transduction that functions as part of a nuclear E3 ubiquitin ligase. COP1 possesses a leucine-rich nuclear-exclusion signal that resides in a domain implicated in COP1 dimerization. BRET was applied in conjunction with site-directed mutagenesis to explore the respective contributions of the nuclear-exclusion and dimerization motifs to the regulation of COP1 activity in vivo. One specific mutant protein, COP1L105A, showed increased nuclear accumulation but retained the ability to dimerize, as monitored by BRET, whereas other mutations inhibited both nuclear exclusion and COP1 dimerization. Mutant rescue and overexpression experiments indicated that nuclear exclusion of COP1 protein is a rate-limiting step in light signal transduction. PMID:15084749

  11. Animal embryonic stem (ES) cells: self-renewal, pluripotency, transgenesis and nuclear transfer.

    PubMed

    Saito, Shigeo; Liu, Bingbing; Yokoyama, Kazunari

    2004-09-01

    Mouse embryonic stem (ES) cells can be maintained indefinitely in the presence of leukemia inhibitory factor (LIF) and they express markers of self-renewal and pluripotency, which include the transcription factor Oct 4, STAT-3, stage-specific embryonic antigen (SSEA)-1, and alkaline phosphatase (AP). Upon removal of LIF, from the culture medium they cease to express markers such as Oct 4, rapidly losing the capacity for self-renewal and differentiating into a variety of cell types. Gene targeting is feasible in murine ES cells because these cells can be maintained in an undifferentiated state long enough to allow selection of properly targeted cell colonies with a high frequency of homologous recombination. Furthermore, blastocysts cloned from cultured murine ES cells develop to term at an efficiency (10-30%) that is three to ten times higher than blastocysts cloned from the nuclei of differentiated somatic cells. It seems likely that ES cells require less extensive reprogramming than do somatic cells, perhaps because in ES cells, many genes that are essential for early development are already active and thus do not require reactivation. Recently, we succeeded in isolating immortalized equine and bovine ES cells with a normal karyotype, that exhibit features similar to those of murine ES cells and express Oct 4, STAT-3, SSEA-1 and AP. We further confirmed the pluripotential ability of these cells, which were able to undergo somatic differentiation in vitro to neural progenitors and to endothelial or hematopoietic lineages. We were able to use bovine ES cells, as a source of nuclei for nuclear transfer (NT) and we generated cloned cattle with a higher frequency of pregnancies to term than has been achieved with differentiated somatic cells. Moreover, bovine ES cells that expressed enhanced green fluorescent protein (EGFP) were incorporated into both the inner cell mass (ICM) and the trophectdermal cells of developing blastocysts. These findings should facilitate

  12. Effective Oocyte Vitrification and Survival Techniques for Bovine Somatic Cell Nuclear Transfer.

    PubMed

    Park, Min Jee; Lee, Seung Eun; Kim, Eun Young; Lee, Jun Beom; Jeong, Chang Jin; Park, Se Pill

    2015-06-01

    Bovine somatic cell nuclear transfer (SCNT) using vitrified-thawed (VT) oocytes has been studied; however, the cloning efficiency of these oocytes is not comparable with that of nonvitrified (non-V) fresh oocytes. This study sought to optimize the survival and cryopreservation of VT oocytes for SCNT. Co-culture with feeder cells that had been preincubated for 15 h significantly improved the survival of VT oocytes and their in vitro developmental potential following SCNT in comparison to co-culture with feeder cells that had been preincubated for 2, 5, or 24 h (p<0.05). Spindle assessment via the Oosight Microscopy Imaging System and microtubule staining revealed that vitrified metaphase II oocytes (VT group) were not suitable for SCNT. However, enucleating and/or activating oocytes prior to freezing enhanced their developmental potential and suitability for SCNT. The cloning efficiency of the enucleated-activated-vitrified-thawed (EAVT) group (21.6%) was better than that of the other vitrification groups [enucleated-vitrified-thawed (EVT) group, 13.7%; VT group, 15.0%; p<0.05] and was comparable with that of the non-V group (25.9%). The reactive oxygen species level was significantly lower in the EAVT group than in the other vitrification groups (p<0.05). mRNA levels of maternal genes (ZAR1, BMP15, and NLRP5) and a stress gene (HSF1) were lower in the vitrification groups than in the non-V group (p<0.05), whereas the level of phospho-p44/42 mitogen-activated protein kinase did not differ among the groups. Among the vitrification groups, blastocysts in the EAVT group had the best developmental potential, as judged by their high mRNA expression of developmental potential-related genes (POU5f1, Interferon-tau, and SLC2A5) and their low expression of proapoptotic (CASP3) and stress (Hsp70) genes. This study demonstrates that SCNT using bovine frozen-thawed oocytes can be successfully achieved using optimized vitrification and co-culture techniques. PMID:25984830

  13. Rex Rabbit Somatic Cell Nuclear Transfer with In Vitro-Matured Oocytes.

    PubMed

    Liu, Yong; Wang, Huili; Lu, Jinhua; Miao, Yiliang; Cao, Xinyan; Zhang, Ling; Wu, Xiaoqing; Wu, Fengrui; Ding, Biao; Wang, Rong; Luo, Mingjiu; Li, Wenyong; Tan, Jinghe

    2016-06-01

    Somatic cell nuclear transfer (SCNT) requires large numbers of matured oocytes. In vitro-matured (IVM) oocytes have been used in SCNT in many animals. We investigated the use of IVM oocytes in Rex rabbit SCNT using Rex rabbit ovaries obtained from a local abattoir. The meiotic ability of oocytes isolated from follicles of different diameters was studied. Rex rabbit SCNT was optimized for denucleation, activation, and donor cell synchronization. Rex rabbit oocytes grew to the largest diameter (110 μm) when the follicle diameter was 1.0 mm. Oocytes isolated from <0.5-mm follicles lacked the ability to resume meiosis. More than 90% of these oocytes remained in the germinal vesicle (GV) stage after in vitro culture (IVC) for 18 h. Oocytes isolated from >0.7-mm follicles acquired maturation ability. More than 90% of these oocytes matured after IVC for 18 h. The developmental potential of oocytes isolated from >1-mm follicles was greater than that of oocytes isolated from 0.7- to 1.0-mm follicles. The highest activation rates for IVM Rex rabbit oocytes were seen after treatment with 2.5 μM ionomycin for 5 min followed by 2 mM 6-dimethylaminopurine (6-DMAP) and 5 μg/mL cycloheximide (CHX) for 1 h. Ionomycin induced the chromatin of IVM oocytes to protrude from the oocyte surface, promoting denucleation. Fetal fibroblast cells (FFCs) and cumulus cells (CCs) were more suitable for Rex rabbit SCNT than skin fibroblast cells (SFCs) (blastocyst rate was 35.6 ± 2.2% and 38.0 ± 6.0% vs. 19.7 ± 3.1%). The best fusion condition was a 2DC interval for 1 sec, 1.6 kV/cm voltages, and 40 μsec duration in 0.28 M mannitol. In conclusion, the in vitro maturation of Rex rabbit oocytes and SCNT procedures were studied systematically and optimized in this study. PMID:27159389

  14. WEB-BASED INTERSPECIES CORRELATION ESTIMATION (WEB-ICE) FOR ACUTE TOXICITY: USER MANUAL V2

    EPA Science Inventory

    Predictive toxicological models are integral to environmental risk Assessment where data for most species are limited. Web-based Interspecies Correlation Estimation (Web-ICE) models are least square regressions that predict acute toxicity (LC50/LD50) of a chemical to a species, ...

  15. USE OF INTERSPECIES CORRELATION ESTIMATIONS TO PREDICT HC5'S BASED ON QSAR

    EPA Science Inventory

    Dyer, S.D., S. Belanger, J. Chaney, D. Versteeg and F. Mayer. In press. Use of Interspecies Correlation Estimations to predict HC5's Based on QSARs (Abstract). To be presented at the SETAC Europe 14th Annual Meeting: Environmental Science Solution: A Pan-European Perspective, 18-...

  16. Augmenting Species Diversity in Water Quality Criteria Derivation using Interspecies Correlation Models

    EPA Science Inventory

    The specific requirements for taxa diversity of the 1985 guidelines have limited the number of ambient water quality criteria (AWQC) developed for aquatic life protection. The EPA developed the Web-based Interspecies Correlation Estimation (Web-ICE) tool to allow extrapolation of...

  17. USE OF INTERSPECIES CORRELATION ESTIMATIONS TO PREDICT HC5'S BASED ON MINIMAL DATA

    EPA Science Inventory

    Dyer, S., S. Belanger, J. Chaney, D. Versteeg and F. Mayer. In press. Use of Interspecies Correlation Estimations to Predict HC5's Based on Minimal Data (Abstract). To be presented at the SETAC Fourth World Congress, 14-18 November 2004, Portland, OR. 1 p. (ERL,GB R1013).

  18. Demonstration of the Web-based Interspecies Correlation Estimation (Web-ICE) modeling application

    EPA Science Inventory

    The Web-based Interspecies Correlation Estimation (Web-ICE) modeling application is available to the risk assessment community through a user-friendly internet platform (http://epa.gov/ceampubl/fchain/webice/). ICE models are log-linear least square regressions that predict acute...

  19. Development of Algal Interspecies Correlation Estimation Models for Chemical Hazard Assessment

    EPA Science Inventory

    Web-based Interspecies Correlation Estimation (ICE) is an application developed to predict the acute toxicity of a chemical from 1 species to another taxon. Web-ICE models use the acute toxicity value for a surrogate species to predict effect values for other species, thus potent...

  20. Being Nature: Interspecies Articulation as a Species-Specific Practice of Relating to Environment

    ERIC Educational Resources Information Center

    Rautio, Pauliina

    2013-01-01

    Rather than categorically teaching us ways to be less anthropocentric, environmental education could be about educating us of the ways in which we already are nature as human animals. In this paper, one species-specific practice of human relating to environment--interspecies articulation--is argued as one way of being nature. Interspecies…

  1. Investigation of Interspecies Interactions within Marine Micromonosporaceae Using an Improved Co-Culture Approach

    PubMed Central

    Adnani, Navid; Vazquez-Rivera, Emmanuel; Adibhatla, Srikar N.; Ellis, Gregory A.; Braun, Doug R.; Bugni, Tim S.

    2015-01-01

    With respect to bacterial natural products, a significant outcome of the genomic era was that the biosynthetic potential in many microorganisms surpassed the number of compounds isolated under standard laboratory growth conditions, particularly among certain members in the phylum Actinobacteria. Our group, as well as others, investigated interspecies interactions, via co-culture, as a technique to coax bacteria to produce novel natural products. While co-culture provides new opportunities, challenges exist and questions surrounding these methods remain unanswered. In marine bacteria, for example, how prevalent are interspecies interactions and how commonly do interactions result in novel natural products? In an attempt to begin to answer basic questions surrounding co-culture of marine microorganisms, we have tested both antibiotic activity-based and LC/MS-based methods to evaluate Micromonosporaceae secondary metabolite production in co-culture. Overall, our investigation of 65 Micromonosporaceae led to the identification of 12 Micromonosporaceae across three genera that produced unique metabolites in co-culture. Our results suggest that interspecies interactions were prevalent between marine Micromonosporaceae and marine mycolic acid-containing bacteria. Furthermore, our approach highlights a sensitive and rapid method for investigating interspecies interactions in search of novel antibiotics, secondary metabolites, and genes. PMID:26404321

  2. Effect of Cell Cycle Interactions and Inhibition of Histone Deacetylases on Development of Porcine Embryos Produced by Nuclear Transfer.

    PubMed

    Rissi, Vitor B; Glanzner, Werner G; Mujica, Lady K S; Antoniazzi, Alfredo Q; Gonçalves, Paulo B D; Bordignon, Vilceu

    2016-02-01

    The aim of this study was to evaluate if the positive effects of inhibiting histone deacetylase enzymes on cell reprogramming and development of somatic cell nuclear transfer (SCNT) embryos is affected by the cell cycle stage of nuclear donor cells and host oocytes at the time of embryo reconstruction. SCNT embryos were produced with metaphase II (MII) or telophase II (TII) cytoplasts and nuclear donor cells that were either at the G1-0 or G2/M stages. Embryos reconstructed with the different cell cycle combinations were treated or not with the histone deacetylase inhibitor (HDACi) Scriptaid for 15 h and then cultured in vitro for 7 days. Embryos reconstructed with MII-G1-0 and TII-G2/M developed to the blastocyst stage with a higher frequency compared to the other groups, confirming the importance of cell cycle interactions on cell reprogramming and SCNT embryo development. Treatment with HDACi improved development of SCNT embryos produced with MII but not TII cytoplasts, independently of the cell cycle stage of nuclear donor cells. These findings provide evidence that the positive effect of HDACi treatment on development of SCNT embryos depends upon cell cycle interactions between the host cytoplast and the nuclear donor cells. PMID:27281695

  3. Nuclear transfer nTreg model reveals fate-determining TCR-β and novel peripheral nTreg precursors.

    PubMed

    Ku, Manching; Chang, Shih-En; Hernandez, Julio; Abadejos, Justin R; Sabouri-Ghomi, Mohsen; Muenchmeier, Niklas J; Schwarz, Anna; Valencia, Anna M; Kirak, Oktay

    2016-04-19

    To study the development and function of "natural-arising" T regulatory (nTreg) cells, we developed a novel nTreg model on pure nonobese diabetic background using epigenetic reprogramming via somatic cell nuclear transfer. On RAG1-deficient background, we found that monoclonal FoxP3(+)CD4(+)Treg cells developed in the thymus in the absence of other T cells. Adoptive transfer experiments revealed that the thymic niche is not a limiting factor in nTreg development. In addition, we showed that the T-cell receptor (TCR) β-chain of our nTreg model was not only sufficient to bias T-cell development toward the CD4 lineage, but we also demonstrated that this TCR β-chain was able to provide stronger TCR signals. This TCR-β-driven mechanism would thus unify former per se contradicting hypotheses of TCR-dependent and -independent nTreg development. Strikingly, peripheral FoxP3(-)CD4(+)T cells expressing the same TCR as this somatic cell nuclear transfer nTreg model had a reduced capability to differentiate into Th1 cells but were poised to differentiate better into induced nTreg cells, both in vitro and in vivo, representing a novel peripheral precursor subset of nTreg cells to which we refer to as pre-nTreg cells. PMID:27044095

  4. Specific features of external heat and mass transfer in the vibration apparatuses used for regenerating spent fuel from nuclear power plants

    NASA Astrophysics Data System (ADS)

    Sapozhnikov, B. G.; Gorbunova, A. M.; Zelenkova, Yu. O.; Sapozhnikov, G. B.; Shiryaeva, N. P.

    2014-06-01

    We present experimental data on the coefficients of heat and mass transfer for freely floating bodies simulating fragments of cladding and large conglomerates of fuel, as well as on the local coefficients of heat and mass transfer over the bed height, which point to high intensity of heat and mass transfer processes that take place in the elements of vibration apparatuses intended for subjecting spent fuel from nuclear power plants to oxidative recrystallization.

  5. Summarizing lecture: factors influencing enzymatic H-transfers, analysis of nuclear tunnelling isotope effects and thermodynamic versus specific effects

    PubMed Central

    Marcus, R.A

    2006-01-01

    In the articles in this Discussion, a wide variety of topics are treated, including reorganization energy, initially introduced for electron transfers (‘environmentally assisted tunnelling’), nuclear tunnelling, H/D and C12/C13 kinetic isotope effects (KIEs), the effect of changes of distal and nearby amino acid residues using site-directed mutagenesis, and dynamics versus statistical effects. A coordinate-free form of semi-classical theory is used to examine topics on data such as tunnelling versus ‘over-the-barrier’ paths and temperature and pressure effects on KIEs. The multidimensional semi-classical theory includes classically allowed and classically forbidden transitions. More generally, we address the question of relating kinetic to thermodynamic factors, as in the electron transfer field, so learning about specific versus thermodynamic effects in enzyme catalysis and KIEs. PMID:16873131

  6. Radiation heat transfer calculations for the uranium fuel-containment region of the nuclear light bulb engine.

    NASA Technical Reports Server (NTRS)

    Rodgers, R. J.; Latham, T. S.; Krascella, N. L.

    1971-01-01

    Calculation results are reviewed of the radiant heat transfer characteristics in the fuel and buffer gas regions of a nuclear light bulb engine based on the transfer of energy by thermal radiation from gaseous uranium fuel in a neon vortex, through an internally cooled transparent wall, to seeded hydrogen propellant. The results indicate that the fraction of UV energy incident on the transparent walls increases with increasing power level. For the reference engine power level of 4600 megw, it is necessary to employ space radiators to reject the UV radiated energy absorbed by the transparent walls. This UV energy can be blocked by employing nitric oxide and oxygen seed gases in the fuel and buffer gas regions. However, this results in increased UV absorption in the buffer gas which also requires space radiators to reject the heat load.

  7. CFD Simulations of a Flow Mixing and Heat Transfer Enhancement in an Advanced LWR Nuclear Fuel Assembly

    SciTech Connect

    In, Wang-Kee; Chun, Tae-Hyun; Shin, Chang-Hwan; Oh, Dong-Seok

    2007-07-01

    A computational fluid dynamics (CFD) analysis has been performed to investigate a flow-mixing and heat-transfer enhancement caused by a mixing-vane spacer in a LWR fuel assembly which is a rod bundle. This paper presents the CFD simulations of a flow mixing and heat transfer in a fully heated 5x5 array of a rod bundle with a split-vane and hybrid-vane spacer. The CFD prediction at a low Reynolds number of 42,000 showed a reasonably good agreement of the initial heat transfer enhancement with the measured one for a partially heated experiment using a similar spacer structure. The CFD simulation also predicted the decay rate of a normalized Nusselt number downstream of the split-vane spacer which agrees fairly well with those of the experiment and the correlation. The CFD calculations for the split vane and hybrid vane at the LWR operating conditions(Re = 500,000) predicted hot fuel spots in a streaky structure downstream of the spacer, which occurs due to the secondary flow occurring in an opposite direction near the fuel rod. However, the split-vane and hybrid-vane spacers are predicted to significantly enhance the overall heat transfer of a LWR nuclear fuel assembly. (authors)

  8. A double species 23Na and 87Rb Bose-Einstein condensate with tunable miscibility via an interspecies Feshbach resonance

    NASA Astrophysics Data System (ADS)

    Wang, Fudong; Li, Xiaoke; Xiong, Dezhi; Wang, Dajun

    2016-01-01

    We have realized a dual-species Bose-Einstein condensate (BEC) of 23Na and 87Rb atoms and observed its immiscibility. Because of the favorable background intra- and inter-species scattering lengths, stable condensates can be obtained via efficient evaporative cooling and sympathetic cooling without the need for fine tuning of the interactions. Our system thus provides a clean platform for studying inter-species interactions-driven effects in superfluid mixtures. With a Feshbach resonance, we have successfully created double BECs with largely tunable inter-species interactions and studied the miscible-immiscible phase transition.

  9. Adiabatic transfer of coherences in a cluster of coupled nuclear spins

    SciTech Connect

    Lee, Jae-Seung; Cardwell, Kate E.; Khitrin, A. K.

    2005-12-15

    It is experimentally demonstrated that quantum coherences can be efficiently transferred using adiabatic energy-level crossing. In a cluster of six dipolar-coupled proton spins of benzene, oriented by a liquid-crystalline matrix, a single-quantum coherence between one pair of states has been adiabatically transferred to another pair of states, and the superposition survived even after ten successive energy-level crossings.

  10. Sensors and nuclear power. Report by the Technology Transfer Sensors Task Team

    SciTech Connect

    Not Available

    1985-06-01

    The existing sensor systems for the basic process parameters in nuclear power plant operation have limitations with respect to accuracy, ease of maintenance and signal processing. These limitations comprise the economy of nuclear power generation. To reduce the costs and improve performance of nuclear power plant fabrication, operation, maintenance and repair we need to advance the sensor technology being applied in the nuclear industry. The economic viability and public acceptance of nuclear power will depend on how well we direct and apply technological advances to the industry. This report was prepared by a team with members representing a wide range of the nuclear industry embracing the university programs, national laboratories, architect engineers and reactor manufacturers. An intensive effort was made to survey current sensor technology, evaluate future trends and determine development needs. This included literature surveys, visits with utilities, universities, laboratories and organizations outside the nuclear industry. Several conferences were attended to take advantage of the access to experts in selected topics and to obtain opinions. Numerous telephone contacts and exchanges by mail supplemented the above efforts. Finally, the broad technical depth of the team members provided the basis for the stimulating working sessions during which this report was organized and drafted.

  11. Interspecies acetate transfer influences the extent of anaerobic benzoate degradation by syntrophic consortia

    SciTech Connect

    Warikoo, V.; McInerney, M.J.; Suflita, J.M.

    1997-03-01

    Benzoate degradation by an anaerobic, syntrophic bacterium, strain SB, in coculture with Desulfovibrio strain G-11 reached a threshold value which depended on the amount of acetate added, and ranged from about 2.5 to 29.9 {mu}M. Increasing acetate concentrations also uncompetitively inhibited benzoate degradation. The apparent V{sub max} and K{sub m} for benzoate degradation decreased with increasing acetate concentration, but the benzoate degradation capacity (V{sub max}/K{sub m}) of cell suspensions remained comparable. The addition of an acetate-using bacterium to cocultures after the threshold was reached resulted in the degradation of benzoate to below the detection limit. Mathematical simulations showed that the benzoate threshold was not predicted by the inhibitory effect of acetate on benzoate degradation kinetics. With nitrate instead of sulfate as the terminal electron acceptor, no benzoate threshold was observed in the presence of 20 mM acetate even though the degradation capacity was lower with nitrate than with sulfate. When strain SB was grown with a hydrogen-using partner that had a 5-fold lower hydrogen utilization capacity, a 5 to 9-fold lower the benzoate degradation capacity was observed compared to SB/G-11 cocultures. The Gibb`s free energy for benzoate degradation was less negative in cell suspensions with threshold compared to those without threshold. These studies showed that the threshold was not a function of the inhibition of benzoate degradation capacity by acetate, or the toxicity of the undissociated form of acetate. Rather a critical or minimal Gibb`s free energy may exist where thermodynamic constraints preclude further benzoate degradation.

  12. Nuclear spectroscopy study of the isotopes populated via multinucleon transfer in the 90Zr + 208Pb reaction

    SciTech Connect

    Ur, C. A.; Corradi, L.; Stefanini, A. M.; Behera, B. R.; Fioretto, E.; Gadea, A.; Latina, A.; Szilner, S.; Beghini, S.; Farnea, E.; Montagnoli, G.; Scarlassara, F.; Haas, F.; Pollarolo, G.

    2006-08-14

    The present work takes advantage of the multinucleon transfer mechanism between heavy reaction partners to study the population pattern of excited nuclear states in near spherical Zirconium isotopes following the 90Zr + 208Pb reaction at an energy closed to the Coulomb barrier. Both the projectile and the target are well known closed shell nuclei offering an optimum situation for clean experimental and theoretical conditions. Total kinetic energy loss (TKEL) distributions were compared with calculations performed with the GRAZING code. The ability to use the TKEL as a selection tool for the states at different excitation energies was shown.

  13. Thermal expansion of UO2+x nuclear fuel rods from a model coupling heat transfer and oxygen diffusion

    SciTech Connect

    Mihaila, Bogden; Zubelewicz, Aleksander; Stan, Marius; Ramirez, Juan

    2008-01-01

    We study the thermal expansion of UO{sub 2+x} nuclear fuel rod in the context of a model coupling heat transfer and oxygen diffusion discussed previously by J.C. Ramirez, M. Stan and P. Cristea [J. Nucl. Mat. 359 (2006) 174]. We report results of simulations performed for steady-state and time-dependent regimes in one-dimensional configurations. A variety of initial- and boundary-value scenarios are considered. We use material properties obtained from previously published correlations or from analysis of previously published data. All simulations were performed using the commercial code COMSOL Multiphysics{sup TM} and are readily extendable to include multidimensional effects.

  14. Impact of nuclear lattice relaxation on the excitation energy transfer along a chain of π -conjugated molecules

    NASA Astrophysics Data System (ADS)

    Schmid, S. A.; Abbel, R.; Schenning, A. P. H. J.; Meijer, E. W.; Herz, L. M.

    2010-02-01

    We have investigated the extent to which delocalization of the ground-state and excited-state wave functions of a π -conjugated molecule affects the excitation energy transfer (EET) between such molecules. Using femtosecond photoluminescence spectroscopy, we experimentally monitored the EET along well-defined supramolecular chains of extended conjugated molecules. Comparison with Monte Carlo simulations reveals that only a model incorporating a localized emitter and delocalized absorber wave function accurately reproduces these data. Our findings demonstrate that self-localization of the initially excited state, following fast relaxation of the nuclear lattice, has a significant impact on the EET dynamics in molecular assemblies.

  15. Engineering design elements of a two-phase thermosyphon to transfer nuclear thermal energy to a hydrogen plant

    NASA Astrophysics Data System (ADS)

    Sabharwall, Piyush

    Two hydrogen production processes, both powered by Next Generation Nuclear Plant (NGNP), are currently under investigation at the Idaho National Laboratory. The first is high-temperature steam electrolysis utilizing both heat and electricity and the second is thermo-chemical production through the sulfur-iodine process primarily utilizing heat. Both processes require high temperature (>850°C) for enhanced efficiency; temperatures indicative of NGNP. Safety and licensing mandates prudently dictate that the NGNP and the hydrogen production facility be physically isolated, perhaps requiring separation of over 100m. There are several options to transferring multi-megawatt thermal power over such a distance. One option is simply to produce only electricity, transfer by wire to the hydrogen plant, and then reconvert the electric energy to heat via Joule or induction heating. Electrical transport, however, suffers energy losses of 60-70% due to the thermal to electric conversion inherent in the Brayton cycle. A second option is thermal energy transport via a single-phase forced convection loop where a fluid is mechanically pumped between heat exchangers at the nuclear and hydrogen plants. High temperatures, however, present unique materials and pumping challenges. Single phase, low pressure helium is an attractive option for NGNP, but is not suitable for a single purpose facility dictated to hydrogen production because low pressure helium requires higher pumping power and makes the process very inefficient. A third option is two-phase heat transfer utilizing a high temperature thermosyphon. Heat transport occurs via evaporation and condensation, and the heat transport fluid is re-circulated by gravitational force. Thermosyphon has the capability to transport heat at high rates over appreciable distances, virtually isothermally and without any requirement for external pumping devices. For process heat, intermediate heat exchangers (IHX) are desired to transfer heat from

  16. Conventional and Bimodal Nuclear Thermal Rocket (NTR) Artificial Gravity Mars Transfer Vehicle Concepts

    NASA Technical Reports Server (NTRS)

    Borowski, Stanley K.; McCurdy, David R.; Packard, Thomas W.

    2014-01-01

    A variety of countermeasures have been developed to address the debilitating physiological effects of "zero-gravity" (0-g) experienced by cosmonauts and astronauts during their approximately 0.5-1.2 year long stays in LEO (Low Earth Orbit). Longer interplanetary flights, combined with possible prolonged stays in Mars orbit, could subject crewmembers to up to approximately 2.5 years of weightlessness. In view of known and recently diagnosed problems associated with 0-g, an artificial gravity spacecraft offers many advantages and may indeed be an enabling technology for human flights to Mars. A number of important human factors must be taken into account in selecting the rotation radius, rotation rate, and orientation of the habitation module or modules. These factors include the gravity gradient effect, radial and tangential Coriolis forces, along with cross-coupled acceleration effects. Artificial gravity (AG) Mars transfer vehicle (MTV) concepts are presented that utilize both conventional NTR, as well as, enhanced "bimodal" nuclear thermal rocket (BNTR) propulsion. The NTR is a proven technology that generates high thrust and has a specific impulse (I (sub sp)) capability of approximately 900 s - twice that of today's best chemical rockets. The AG/MTV concepts using conventional NTP carry twin cylindrical "ISS-type" habitation modules with their long axes oriented either perpendicular or parallel to the longitudinal spin axis of the MTV and utilize photovoltaic arrays (PVAs) for spacecraft power. The twin habitat modules are connected to a central operations hub located at the front of the MTV via two pressurized tunnels that provide the rotation radius for the habitat modules. For the BNTR AG/MTV option, each engine has its own "closed" secondary helium-xenon gas loop and Brayton rotating unit that can generate tens of kilowatts (kW (sub e)) of spacecraft electrical power during the mission coast phase eliminating the need for large PVAs. A single inflatable

  17. Quantile-Quantile Plots:. AN Approach for the Inter-Species Comparison of Promoter Architecture in Eukaryotes

    NASA Astrophysics Data System (ADS)

    Feldmeier, Kaspar; Kilian, Joachim; Harter, Klaus; Wanke, Dierk; Berendzen, Kenneth W.

    2011-01-01

    Regulatory non-coding DNA is important to drive gene transcription and thereby influence mRNA and consequently protein abundance. Therefore, biologists and bioinformation scientists aim to extract meaningful information from these sequence regions, in particular upstream regulation regions called promoters, and conclude on regulatory sequence function. While some approaches have been successful for single genes or a single genome, it is an open question whether information on promoter function can readily be transferred between different species. Thus, it is useful for biologists to know more about the general structure and composition of promoters including the occurrence of cisregulatory DNA-elements (CREs) to be able to compare promoter architecture between organisms. To approach this task, we utilized the fully sequenced genomes of the plant model organisms: mouse-ear cress (Arabidopsis thaliana), western balsam poplar (Populus trichocarpa), Sorghum bicolor and rice (Oryza sativa). For the interspecies comparison we made use of quantile-quantile (QQ)-plots of the variances of hexanucleotides or known functional CREs of core-promoter regions. Here, we suggest that the differences in promoter architecture correlate with the sizes of the intergenic space, i.e. regions, in which the promoters are located. In contrast, analysis of CREs is hampered by the general lack of well characterized transcription factor-CRE-relationships.

  18. Computational analysis of four human adenovirus type 4 genomes reveals molecular evolution through two interspecies recombination events

    PubMed Central

    Dehghan, Shoaleh; Seto, Jason; Liu, Elizabeth B.; Walsh, Michael P.; Dyer, David W.; Chodosh, James; Seto, Donald

    2013-01-01

    Computational analysis of human adenovirus type 4 (HAdV-E4), a pathogen that is the only HAdV member of species E, provides insights into its zoonotic origin and molecular adaptation. Its genome encodes a domain of the major capsid protein, hexon, from HAdV-B16 recombined into the genome chassis of a simian adenovirus. Genomes of two recent field strains provide a clue to its adaptation to the new host: recombination of a NF-I binding site motif, which is required for efficient viral replication, from another HAdV genome. This motif is absent in the chimpanzee adenoviruses and the HAdV-E4 prototype, but is conserved amongst other HAdVs. This is the first report of an interspecies recombination event for HAdVs, and the first documentation of a lateral partial gene transfer from a chimpanzee AdV. The potential for such recombination events are important when considering chimpanzee adenoviruses as candidate gene delivery vectors for human patients. PMID:23763770

  19. Nuclear fragmentation energy and momentum transfer distributions in relativistic heavy-ion collisions

    NASA Technical Reports Server (NTRS)

    Khandelwal, Govind S.; Khan, Ferdous

    1989-01-01

    An optical model description of energy and momentum transfer in relativistic heavy-ion collisions, based upon composite particle multiple scattering theory, is presented. Transverse and longitudinal momentum transfers to the projectile are shown to arise from the real and absorptive part of the optical potential, respectively. Comparisons of fragment momentum distribution observables with experiments are made and trends outlined based on our knowledge of the underlying nucleon-nucleon interaction. Corrections to the above calculations are discussed. Finally, use of the model as a tool for estimating collision impact parameters is indicated.

  20. MicroRNA-34c Expression in Donor Cells Influences the Early Development of Somatic Cell Nuclear Transfer Bovine Embryos

    PubMed Central

    Wang, Bo; Wang, Yongsheng; Zhang, Man; Du, Yue; Zhang, Yijun; Xing, Xupeng; Zhang, Lei; Su, JianMin

    2014-01-01

    Abstract The essence of the reprogramming activity of somatic cell nuclear transfer (SCNT) embryos is to produce normal fertilized embryos. However, reprogramming of somatic cells is not as efficient as the reprogramming of sperm. In this report, we describe the effect of an inducible, specific miR-34 microRNA expression in donor cells that enables a similar level of sperm:transgene expression on the early development of SCNT embryos. Our results showed that donor cells with doxycycline (dox)-induced miR-34c expression for the preparation of SCNT embryos resulted in altered developmental rates, histone modification (H3K9ac and H3K4me3), and extent of apoptosis. The cleavage rate and blastocyst formation of the induced nuclear transfer (NT) group were significantly increased. The immunofluorescence signal of H3K9ac in embryos in the induced NT group significantly increased in two-cell- and eight-cell-stage embryos; that of H3K4me3 increased significantly in eight-cell-stage embryos. Although significant differences in staining signals of apoptosis were not detected between groups, lower apoptosis levels were observed in the induced NT group. In conclusion, miR-34c expression induced by dox treatment enhances the developmental potential of SCNT embryos, modifies the epigenetic status, and changes blastocyst quality. PMID:25437869

  1. Generation of embryonic stem cells from mouse adipose-tissue derived cells via somatic cell nuclear transfer

    PubMed Central

    Qin, Yiren; Qin, Jilong; Zhou, Chikai; Li, Jinsong; Gao, Wei-Qiang

    2015-01-01

    Somatic cells can be reprogrammed into embryonic stem cells (ESCs) by nuclear transfer (NT-ESCs), or into induced pluripotent stem cells (iPSCs) by the “Yamanaka method.” However, recent studies have indicated that mouse and human iPSCs are prone to epigenetic and transcriptional aberrations, and that NT-ESCs correspond more closely to ESCs derived from in vitro fertilized embryos than iPSCs. In addition, the procedure of NT-ESCs does not involve gene modification. Demonstration of generation of NT-ESCs using an easily-accessible source of adult cell types would be very important. Adipose tissue is a source of readily accessible donor cells and can be isolated from both males and females at different ages. Here we report that NT-ESCs can be generated from adipose tissue-derived cells (ADCs). At morphological, mRNA and protein levels, these NT-ESCs show classic ESC colonies, exhibit alkaline phosphatase (AP) activity, and display normal diploid karyotypes. Importantly, these cells express pluripotent markers including Oct4, Sox2, Nanog and SSEA-1. Furthermore, they can differentiate in vivo into various types of cells from 3 germinal layers by teratoma formation assays. This study demonstrates for the first time that ESCs can be generated from the adipose tissue by somatic cell nuclear transfer (SCNT) and suggests that ADCs can be a new donor-cell type for potential therapeutic cloning. PMID:25692793

  2. Comparison of Species Sensitivity Distributions Derived from Interspecies Correlation Models to Distributions used to Derive Water Quality Criteria

    EPA Science Inventory

    Species sensitivity distributions (SSD) require a large number of measured toxicity values to define a chemical’s toxicity to multiple species. This investigation comprehensively evaluated the accuracy of SSDs generated from toxicity values predicted from interspecies correlation...

  3. Influence of Taxonomic Relatedness and Chemical Mode of Action in Acute Interspecies Estimation Models for Aquatic species

    EPA Science Inventory

    Ecological risks to aquatic organisms are typically assessed using toxicity data for relatively few species and with limited understanding of relative species sensitivity. We developed a comprehensive set of interspecies correlation estimation (ICE) models for aquatic organisms a...

  4. Factors Determining the Efficiency of Porcine Somatic Cell Nuclear Transfer: Data Analysis with Over 200,000 Reconstructed Embryos.

    PubMed

    Liu, Tianbin; Dou, Hongwei; Xiang, Xi; Li, Lin; Li, Yong; Lin, Lin; Pang, Xinzhi; Zhang, Yijie; Chen, Yu; Luan, Jing; Xu, Ying; Yang, Zhenzhen; Yang, Wenxian; Liu, Huan; Li, Feida; Wang, Hui; Yang, Huanming; Bolund, Lars; Vajta, Gabor; Du, Yutao

    2015-12-01

    Data analysis in somatic cell nuclear transfer (SCNT) research is usually limited to several hundreds or thousands of reconstructed embryos. Here, we report mass results obtained with an established and consistent porcine SCNT system (handmade cloning [HMC]). During the experimental period, 228,230 reconstructed embryos and 82,969 blastocysts were produced. After being transferred into 656 recipients, 1070 piglets were obtained. First, the effects of different types of donor cells, including fetal fibroblasts (FFs), adult fibroblasts (AFs), adult preadipocytes (APs), and adult blood mesenchymal (BM) cells, were investigated on the further in vitro and in vivo development. Compared to adult donor cells (AFs, APs, BM cells, respectively), FF cells resulted in a lower blastocyst/reconstructed embryo rate (30.38% vs. 37.94%, 34.65%, and 34.87%, respectively), but a higher overall efficiency on the number of piglets born alive per total blastocysts transferred (1.50% vs. 0.86%, 1.03%, and 0.91%, respectively) and a lower rate of developmental abnormalities (10.87% vs. 56.57%, 24.39%, and 51.85%, respectively). Second, recloning was performed with cloned adult fibroblasts (CAFs) and cloned fetal fibroblasts (CFFs). When CAFs were used as the nuclear donor, fewer developmental abnormalities and higher overall efficiency were observed compared to AFs (56.57% vs. 28.13% and 0.86% vs. 1.59%, respectively). However, CFFs had an opposite effect on these parameters when compared with CAFs (94.12% vs. 10.87% and 0.31% vs. 1.50%, respectively). Third, effects of genetic modification on the efficiency of SCNT were investigated with transgenic fetal fibroblasts (TFFs) and gene knockout fetal fibroblasts (KOFFs). Genetic modification of FFs increased developmental abnormalities (38.96% and 25.24% vs. 10.87% for KOFFs, TFFs, and FFs, respectively). KOFFs resulted in lower overall efficiency compared to TFFs and FFs (0.68% vs. 1.62% and 1.50%, respectively). In conclusion, this is the

  5. Nuclear and Q{sup 2} dependence of quaselastic (e,e{prime}p) scattering at large momentum transfer

    SciTech Connect

    Jackson, H.E.; Geesaman, D.F.; Jones, C.E.

    1995-08-01

    An experiment was completed at the Stanford Linear Accelerator Center in which measurements of the (e,e{prime}p) coincidence quasielastic cross section in nuclei were extended to the largest possible Q{sup 2} attainable with the Nuclear Physics Injector and the End Station A spectrometers. Coincidence measurements of the quasielastic (e,e{prime}p) cross section were made on nuclei from carbon to gold in the Q{sup 2} range of 1-7 (GeV/c){sup 2}. Several papers describing the results were published or submitted. Analysis of the data is in its final stages. In summary, the cross section for quasielastic {sup 12}C(e,e{prime}p) scattering was measured at momentum transfer Q{sup 2}=1, 3, 5, and 6.8 (GeV/c){sup 2}. The results are consistent with scattering from a single nucleon as the dominant process. The nuclear transparency is obtained and compared with theoretical calculations that incorporate color transparency effects. No significant rise of the transparency with Q{sup 2} is observed. Cross sections were reported for the reaction {sup 2}H(e,e{prime}p)n for momentum transfers in the range 1.2 {<=}Q{sup 2}{<=}6.8 (GeV/c){sup 2} and for missing momenta from 0 to 250 MeV/c. The longitudinal-transverse interference structure function was separated at Q{sup 2}=1.5 (GeV/c){sup 2}. The observables were compared to calculations performed in nonrelativistic and relativistic frameworks. The data are best described by a fully relativistic calculation. The A-dependence of the quasielastic A(e,e{prime}p) reaction was studied with {sup 2}H, C, Fe, and Au nuclei at momentum transfers Q{sup 2}=1, 3, 5, and 6.8 (GeV/c){sup 2}. The nuclear transparency T A,Q{sup 2}, a measure of the average probability that the struck proton escapes from the nucleu A without interaction, was extracted. Several calculations predict a significant increase in T with momentum transfer, a phenomenon known as color transparency. No significant rise within errors is seen for any of the nuclei studied.

  6. Robotics and nuclear power. Report by the Technology Transfer Robotics Task Team

    SciTech Connect

    Not Available

    1985-06-01

    A task team was formed at the request of the Department of Energy to evaluate and assess technology development needed for advanced robotics in the nuclear industry. The mission of these technologies is to provide the nuclear industry with the support for the application of advanced robotics to reduce nuclear power generating costs and enhance the safety of the personnel in the industry. The investigation included robotic and teleoperated systems. A robotic system is defined as a reprogrammable, multifunctional manipulator designed to move materials, parts, tools, or specialized devices through variable programmed motions for the performance of a variety of tasks. A teleoperated system includes an operator who remotely controls the system by direct viewing or through a vision system.

  7. Methyl-CpG-Binding Protein 2 Improves the Development of Mouse Somatic Cell Nuclear Transfer Embryos.

    PubMed

    Wang, Zhen-Dong; Duan, Lian; Zhang, Zi-Hui; Song, Si-Hang; Bai, Guang-Yu; Zhang, Na; Shen, Xing-Hui; Shen, Jing-Ling; Lei, Lei

    2016-04-01

    Methyl-CpG-binding domain proteins (MBPs) connect DNA methylation and histone modification, which are the key changes of somatic cell reprogramming. Methyl-CpG-binding protein 2 (MeCP2) was the first discovered MBP that has been extensively studied in the neurodevelopmental disorder Rett syndrome. However, a role for MeCP2 during cellular reprogramming associated with somatic cell nuclear transfer (SCNT) has not been examined. In this study, we discovered that MeCP2 expression was significantly lower in embryos generated by SCNT compared with those generated by intracytoplasmic sperm injection (ICSI). We genetically modified mouse embryonic fibroblasts (MEFs) to overexpress MeCP2 and serve as donor cells for nuclear transfer (NT) to investigate the effects of MeCP2 on preimplantation development of SCNT embryos. The blastocyst rate (35.71%) of MeCP2 overexpressed embryos (NT(+)) was significantly greater than in nontransgenic embryos (NT(-), 24.29%). Furthermore, immunofluorescence experiments revealed that 5-methylcytosine (5mC) was transferred to 5-hydroxymethylcytosine (5hmC) to a greater extent in NT(+) embryos than in NT(-) embryos. Real-time PCR evaluation of gene expression also showed that embryonic development-associated genes, such as Oct4 and Nanog, were significantly higher in the NT(+) group compared to the NT(-) group. Collectively, these results suggested that MeCP2 facilitated Tet3 activity, enhanced expression of pluripotency-related genes, and eventually improved the development of NT embryos. Finally, we performed chromatin immunoprecipitation to identify direct targets of MeCP2 and constructed a protein interaction network to elucidate several putative MeCP2 targets. PMID:26982160

  8. No differences in sheep somatic cell nuclear transfer outcomes using serum-starved or actively growing donor granulosa cells.

    PubMed

    Peura, T T; Hartwich, K M; Hamilton, H M; Walker, S K

    2003-01-01

    The aim of this study was to compare serum-starved and non-starved donor cells in sheep nuclear transfer with a special emphasis on cloning outcomes. Sheep oocytes, derived either in vivo or in vitro, were fused with cultured serum-starved or actively growing adult granulosa cells. Resulting blastocysts were transferred to recipients fresh or after vitrification, and subsequent pregnancies followed to term. Donor cell treatment did not significantly affect preimplantation development, pregnancy rates, fetal loss or neonate survival rates. Of 22 lambs born, ten survived the immediate perinatal period but all succumbed at various timepoints within the first few weeks of life. The results of the study suggest that the use of serum-starved cells offers no advantages or disadvantages to cloning outcomes. Neither were significant differences in outcomes observed when using either in vivo- or in vitro-derived oocytes or embryos transferred fresh or after vitrification. Yet, these results continue to highlight problems associated with somatic cell cloning as indicated by offspring mortality. It remains unclear whether the high offspring mortality in the current study was related to species, associated with the cell lines used or the result of other causes. PMID:12921702

  9. Transfer of elements relevant to nuclear fuel cycle from soil to boreal plants and animals in experimental meso- and microcosms.

    PubMed

    Tuovinen, Tiina S; Kasurinen, Anne; Häikiö, Elina; Tervahauta, Arja; Makkonen, Sari; Holopainen, Toini; Juutilainen, Jukka

    2016-01-01

    Uranium (U), cobalt (Co), molybdenum (Mo), nickel (Ni), lead (Pb), thorium (Th) and zinc (Zn) occur naturally in soil but their radioactive isotopes can also be released into the environment during the nuclear fuel cycle. The transfer of these elements was studied in three different trophic levels in experimental mesocosms containing downy birch (Betula pubescens), narrow buckler fern (Dryopteris carthusiana) and Scandinavian small-reed (Calamagrostis purpurea ssp. Phragmitoides) as producers, snails (Arianta arbostorum) as herbivores, and earthworms (Lumbricus terrestris) as decomposers. To determine more precisely whether the element uptake of snails is mainly via their food (birch leaves) or both via soil and food, a separate microcosm experiment was also performed. The element uptake of snails did not generally depend on the presence of soil, indicating that the main uptake route was food, except for U, where soil contact was important for uptake when soil U concentration was high. Transfer of elements from soil to plants was not linear, i.e. it was not correctly described by constant concentration ratios (CR) commonly applied in radioecological modeling. Similar nonlinear transfer was found for the invertebrate animals included in this study: elements other than U were taken up more efficiently when element concentration in soil or food was low. PMID:26363398

  10. Finite-temperature behavior of an interspecies fermionic superfluid with population imbalance

    SciTech Connect

    Guo Hao; Chien, C.-C.; He Yan; Levin, K.; Chen Qijin

    2009-07-15

    We determine the superfluid transition temperature T{sub c} and related finite temperature phase diagrams for the entire BCS-Bose-Einstein-condensation crossover in a three-dimensional homogeneous mixture of {sup 6}Li and {sup 40}K atoms with population imbalance. Our work is motivated by the recent observation of an interspecies Feshbach resonance. Pairing fluctuation effects, which significantly reduce T{sub c} from the onset temperature for pairing (T*), provide reasonable estimates of T{sub c} and indicate that the interspecies superfluid phase should be accessible in future experiments. Although a homogeneous polarized superfluid is not stable in the ground state near unitarity, our phase diagrams show that it stabilizes at finite temperature.

  11. Interspecies Systems Biology Uncovers Metabolites Affecting C. elegans Gene Expression and Life History Traits

    PubMed Central

    Watson, Emma; MacNeil, Lesley T.; Ritter, Ashlyn D.; Yilmaz, L. Safak; Rosebrock, Adam P.; Caudy, Amy A.; Walhout, Albertha J. M.

    2014-01-01

    SUMMARY Diet greatly influences gene expression and physiology. In mammals, elucidating the effects and mechanisms of individual nutrients is challenging due to the complexity of both the animal and its diet. Here we used an interspecies systems biology approach with Caenorhabditis elegans and two if its bacterial diets, Escherichia coli and Comamonas aquatica, to identify metabolites that affect the animal’s gene expression and physiology. We identify vitamin B12 as the major dilutable metabolite provided by Comamonas aq. that regulates gene expression, accelerates development and reduces fertility, but does not affect lifespan. We find that vitamin B12 has a dual role in the animal: it affects development and fertility via the methionine/S-Adenosylmethionine (SAM) cycle and breaks down the short-chain fatty acid propionic acid preventing its toxic buildup. Our interspecies systems biology approach provides a paradigm for understanding complex interactions between diet and physiology. PMID:24529378

  12. Formation of interspecies fusants of Agaricus bisporus and Agaricus bitorquis mushroom by protoplast fusion.

    PubMed

    Singh, Rana Inder; Aarti, Kanojiya; Singh, Sandhu Sardul

    2007-12-01

    Interspecies fusants are formed between Agaricus bisporus and Agaricus bitorquis by protoplast fusion technique. Protoplasts were isolated and regenerated by using Novozyme 234 lytic enzyme. Twenty slow growing isolates were separated from the protoplast regenerated colonies, which were assumed as homokaryons (putative homokaryons). These twenty isolates were subjected to growth rate, colony morphology and spawn run studies for screening of true homokaryons. Antifungal markers were developed for selection of fusants. PMID:23100692

  13. Radiocesium transfer from hillslopes to the Pacific Ocean after the Fukushima Nuclear Power Plant accident: A review.

    PubMed

    Evrard, Olivier; Laceby, J Patrick; Lepage, Hugo; Onda, Yuichi; Cerdan, Olivier; Ayrault, Sophie

    2015-10-01

    The devastating tsunami triggered by the Great East Japan Earthquake on March 11, 2011 inundated the Fukushima Dai-ichi Nuclear Power Plant (FDNPP) resulting in a loss of cooling and a series of explosions releasing the largest quantity of radioactive material into the atmosphere since the Chernobyl nuclear accident. Although 80% of the radionuclides from this accidental release were transported over the Pacific Ocean, 20% were deposited over Japanese coastal catchments that are subject to frequent typhoons. Among the radioisotopes released during the FDNPP accident, radiocesium ((134)Cs and (137)Cs) is considered the most serious current and future health risk for the local population. The goal of this review is to synthesize research relevant to the transfer of FDNPP derived radiocesium from hillslopes to the Pacific Ocean. After radiocesium fallout deposition on vegetation and soils, the contamination may remain stored in forest canopies, in vegetative litter on the ground, or in the soil. Once radiocesium contacts soil, it is quickly and almost irreversibly bound to fine soil particles. The kinetic energy of raindrops instigates the displacement of soil particles, and their bound radiocesium, which may be mobilized and transported with overland flow. Soil erosion is one of the main processes transferring particle-bound radiocesium from hillslopes through rivers and streams, and ultimately to the Pacific Ocean. Accordingly this review will summarize results regarding the fundamental processes and dynamics that govern radiocesium transfer from hillslopes to the Pacific Ocean published in the literature within the first four years after the FDNPP accident. The majority of radiocesium is reported to be transported in the particulate fraction, attached to fine particles. The contribution of the dissolved fraction to radiocesium migration is only relevant in base flows and is hypothesized to decline over time. Owing to the hydro-meteorological context of the

  14. Contributions of ancestral inter-species recombination to the genetic diversity of extant Streptomyces lineages.

    PubMed

    Andam, Cheryl P; Choudoir, Mallory J; Vinh Nguyen, Anh; Sol Park, Han; Buckley, Daniel H

    2016-07-01

    Streptomyces species produce many important antibiotics and have a crucial role in soil nutrient cycling. However, their evolutionary history remains poorly characterized. We have evaluated the impact of homologous recombination on the evolution of Streptomyces using multi-locus sequence analysis of 234 strains that represent at least 11 species clusters. Evidence of inter-species recombination is widespread but not uniform within the genus and levels of mosaicism vary between species clusters. Most phylogenetically incongruent loci are monophyletic at the scale of species clusters and their subclades, suggesting that these recombination events occurred in shared ancestral lineages. Further investigation of two mosaic species clusters suggests that genes acquired by inter-species recombination may have become fixed in these lineages during periods of demographic expansion; implicating a role for phylogeography in determining contemporary patterns of genetic diversity. Only by examining the phylogeny at the scale of the genus is apparent that widespread phylogenetically incongruent loci in Streptomyces are derived from a far smaller number of ancestral inter-species recombination events. PMID:26849310

  15. Estimates of major anthropogenic halocarbon emissions from China based on interspecies correlations

    NASA Astrophysics Data System (ADS)

    Fang, Xuekun; Wu, Jing; Su, Shenshen; Han, Jiarui; Wu, Yusheng; Shi, Yehong; Wan, Dan; Sun, Xuezhi; Zhang, Jianbo; Hu, Jianxin

    2012-12-01

    Halocarbon emissions from China are of great interest to both policy makers and academia. To estimate halocarbon emissions with interspecies correlation methods, previous studies adopted CO, HCFC-22 or other species as reference tracers. However, few of these studies compared the results using different reference tracers. In this study, chlorofluorocarbons (CFCs), hydrochlorofluorocarbons (HCFCs), hydrofluorocarbons (HFCs) and carbon monoxide (CO) concentrations were measured at a monitoring site in northern China in 2009/2010, and halocarbon emissions were estimated using an interspecies correlation method. A comparison was performed of the correlations between estimated halocarbon emissions and two reference tracers, CO and HCFC-22. The results show that both species are significantly correlated with most of the target species (P < 0.01), whereas HCFC-22 shows better correlations than does CO. Our estimated halocarbon emissions for 2009 agree within uncertainties with results obtained with other approaches, including inverse modeling and interspecies correlation methods. The emissions for 2001-2009 estimated in different studies (all using top-down approaches) show a clear decrease in the emissions of CFC-11 and CFC-12 and an increase in the emissions of HCFC-22, HCFC-141b and HCFC-142b in China. Moreover, the combined Ozone Depletion Potential weighted emissions of CFCs are much greater than the reported consumption, whereas the emissions of HCFC counterparts are not more than one-half of the reported consumption. This result suggests that HCFCs are being accumulated in banks and that these banks will sustain elevated in China.

  16. Retrograde transfer RNA nuclear import provides a new level of tRNA quality control in Saccharomyces cerevisiae

    PubMed Central

    Kramer, Emily B.; Hopper, Anita K.

    2013-01-01

    In eukaryotes, transfer RNAs (tRNAs) are transcribed in the nucleus yet function in the cytoplasm; thus, tRNA movement within the cell was believed to be unidirectional—from the nucleus to the cytoplasm. It is now known that mature tRNAs also move in a retrograde direction from the cytoplasm to the nucleus via retrograde tRNA nuclear import, a process that is conserved from yeast to vertebrates. The biological significance of this tRNA nuclear import is not entirely clear. We hypothesized that retrograde tRNA nuclear import might function in proofreading tRNAs to ensure that only proper tRNAs reside in the cytoplasm and interact with the translational machinery. Here we identify two major types of aberrant tRNAs in yeast: a 5′, 3′ end-extended, spliced tRNA and hypomodified tRNAs. We show that both types of aberrant tRNAs accumulate in mutant cells that are defective in tRNA nuclear traffic, suggesting that they are normally imported into the nucleus and are repaired or degraded. The retrograde pathway functions in parallel with the cytoplasmic rapid tRNA decay pathway previously demonstrated to monitor tRNA quality, and cells are not viable if they lack both pathways. Our data support the hypothesis that the retrograde process provides a newly discovered level of tRNA quality control as a pathway that monitors both end processing of pre-tRNAs and the modification state of mature tRNAs. PMID:24297920

  17. High Power Nuclear Electric Propulsion (NEP) for Cargo and Propellant Transfer Missions in Cislunar Space

    NASA Technical Reports Server (NTRS)

    Falck, Robert D.; Borowski, Stanley K.

    2003-01-01

    The performance of Nuclear Electric Propulsion (NEP) in transporting cargo and propellant from Low Earth Orbit (LEO) to the first Earth-Moon Lagrange point (EML1) is examined. The baseline NEP vehicle utilizes a fission reactor system with Brayton power conversion for electric power generation to power multiple liquid hydrogen magnetoplasmadynamic (MPD) thrusters. Vehicle characteristics and performance levels are based on technology availability in a fifteen to twenty year timeframe. Results of numerical trajectory analyses are also provided.

  18. The Caenorhabditis elegans SUN protein UNC-84 interacts with lamin to transfer forces from the cytoplasm to the nucleoskeleton during nuclear migration

    PubMed Central

    Bone, Courtney R.; Tapley, Erin C.; Gorjánácz, Mátyás; Starr, Daniel A.

    2014-01-01

    Nuclear migration is a critical component of many cellular and developmental processes. The nuclear envelope forms a barrier between the cytoplasm, where mechanical forces are generated, and the nucleoskeleton. The LINC complex consists of KASH proteins in the outer nuclear membrane and SUN proteins in the inner nuclear membrane that bridge the nuclear envelope. How forces are transferred from the LINC complex to the nucleoskeleton is poorly understood. The Caenorhabditis elegans lamin, LMN-1, is required for nuclear migration and interacts with the nucleoplasmic domain of the SUN protein UNC-84. This interaction is weakened by the unc-84(P91S) missense mutation. These mutant nuclei have an intermediate nuclear migration defect—live imaging of nuclei or LMN-1::GFP shows that many nuclei migrate normally, others initiate migration before subsequently failing, and others fail to begin migration. At least one other component of the nucleoskeleton, the NET5/Samp1/Ima1 homologue SAMP-1, plays a role in nuclear migration. We propose a nut-and-bolt model to explain how forces are dissipated across the nuclear envelope during nuclear migration. In this model, SUN/KASH bridges serve as bolts through the nuclear envelope, and nucleoskeleton components LMN-1 and SAMP-1 act as both nuts and washers on the inside of the nucleus. PMID:25057012

  19. Corrigendum to "Coupled thermochemical, isotopic evolution and heat transfer simulations in highly irradiated UO2 nuclear fuel"

    NASA Astrophysics Data System (ADS)

    Piro, M. H. A.; Banfield, J.; Clarno, K.; Simunovic, S.; Besmann, T. M.; Lewis, B. J.; Thompson, W. T.

    2016-09-01

    Figs. 7-9 in "Coupled thermochemical, isotopic evolution and heat transfer simulations in highly irradiated UO2 nuclear fuel" [1] have a consistent error corresponding to the relative proportions of iodine. Reported concentrations of iodine in the original manuscript are approximately ten times higher than expected, and are comparable in atomic proportions to cesium. One would expect that the amount of cesium would be about one order of magnitude greater than iodine based on the difference in fission yields of 235U and 239Pu. A practical consequence of this error would affect the predicted quantity and chemical composition of iodine on the fuel surface, which is related to iodine-induced stress corrosion cracking [2].

  20. Close Interspecies Interactions between Prokaryotes from Sulfureous Environments

    PubMed Central

    Müller, Johannes; Overmann, Jörg

    2011-01-01

    Green sulfur bacteria are obligate photolithoautotrophs that require highly reducing conditions for growth and can utilize only a very limited number of carbon substrates. These bacteria thus inhabit a very narrow ecologic niche. However, several green sulfur bacteria have overcome the limits of immobility by entering into a symbiosis with motile Betaproteobacteria in a type of multicellular association termed phototrophic consortia. One of these consortia, “Chlorochromatium aggregatum,” has recently been established as the first culturable model system to elucidate the molecular basis of this symbiotic interaction. It consists of 12–20 green sulfur bacteria epibionts surrounding a central, chemoheterotrophic betaproteobacterium in a highly ordered fashion. Recent genomic, transcriptomic, and proteomic studies of “C. aggregatum” and its epibiont provide insights into the molecular basis and the origin of the stable association between the two very distantly related bacteria. While numerous genes of central metabolic pathways are upregulated during the specific symbiosis and hence involved in the interaction, only a limited number of unique putative symbiosis genes have been detected in the epibiont. Green sulfur bacteria therefore are preadapted to a symbiotic lifestyle. The metabolic coupling between the bacterial partners appears to involve amino acids and highly specific ultrastructures at the contact sites between the cells. Similarly, the interaction in the equally well studied archaeal consortia consisting of Nanoarchaeum equitans and its host Ignicoccus hospitalis is based on the transfer of amino acids while lacking the highly specialized contact sites observed in phototrophic consortia. PMID:21779277

  1. Photoprotection and triplet energy transfer in higher plants: the role of electronic and nuclear fluctuations.

    PubMed

    Cupellini, Lorenzo; Jurinovich, Sandro; Prandi, Ingrid G; Caprasecca, Stefano; Mennucci, Benedetta

    2016-04-20

    Photosynthetic organisms employ several photoprotection strategies to avoid damage due to the excess energy in high light conditions. Among these, quenching of triplet chlorophylls by neighboring carotenoids (Cars) is fundamental in preventing the formation of singlet oxygen. Cars are able to accept the triplets from chlorophylls by triplet energy transfer (TET). We have here studied TET rates in CP29, a minor light-harvesting complex (LHC) of the Photosystem II in plants. A fully atomistic strategy combining classical molecular dynamics of the LHC in its natural environment with a hybrid time-dependent density functional theory/polarizable MM description of the TET is used. We find that the structural fluctuations of the pigment-protein complex can largely enhance the transfer rates with respect to those predicted using the crystal structure, reducing the triplet quenching times in the subnanosecond scale. These findings add a new perspective for the interpretation of the photoprotection function and its relation with structural motions of the LHC. PMID:27052105

  2. A Multi-Dimensional Heat Transfer Model of a Tie-Tube and Hexagonal Fuel Element for Nuclear Thermal Propulsion

    NASA Technical Reports Server (NTRS)

    Gomez, C. F.; Mireles, O. R.; Stewart, E.

    2016-01-01

    The Space Capable Cryogenic Thermal Engine (SCCTE) effort considers a nuclear thermal rocket design based around a Low-Enriched Uranium (LEU) design fission reactor. The reactor core is comprised of bundled hexagonal fuel elements that directly heat hydrogen for expansion in a thrust chamber and hexagonal tie-tubes that house zirconium hydride moderator mass for the purpose of thermalizing fast neutrons resulting from fission events. Created 3D steady state Hex fuel rod model with 1D flow channels. Hand Calculation were used to set up initial conditions for fluid flow. The Hex Fuel rod uses 1D flow paths to model the channels using empirical correlations for heat transfer in a pipe. Created a 2-D axisymmetric transient to steady state model using the CFD turbulent flow and Heat Transfer module in COMSOL. This model was developed to find and understand the hydrogen flow that might effect the thermal gradients axially and at the end of the tie tube where the flow turns and enters an annulus. The Hex fuel rod and Tie tube models were made based on requirements given to us by CSNR and the SCCTE team. The models helped simplify and understand the physics and assumptions. Using pipe correlations reduced the complexity of the 3-D fuel rod model and is numerically more stable and computationally more time-efficient compared to the CFD approach. The 2-D axisymmetric tie tube model can be used as a reference "Virtual test model" for comparing and improving 3-D Models.

  3. Production of Bovine Embryos and Calves Cloned by Nuclear Transfer Using Mesenchymal Stem Cells from Amniotic Fluid and Adipose Tissue.

    PubMed

    da Silva, Carolina Gonzales; Martins, Carlos Frederico; Cardoso, Tereza Cristina; da Cunha, Elisa Ribeiro; Bessler, Heidi Christina; Martins, George Henrique Lima; Pivato, Ivo; Báo, Sônia Nair

    2016-04-01

    The less differentiated the donor cells are used in nuclear transfer (NT), the more easily are they reprogrammed by the recipient cytoplasm. In this context, mesenchymal stem cells (MSCs) appear as an alternative to donor nuclei for NT. The amniotic fluid and adipose tissue are sources of MSCs that have not been tested for the production of cloned embryos in cattle. The objective of this study was to isolate, characterize, and use MSCs derived from amniotic fluid (MSC-AF) and adipose tissue (MSC-AT) to produce cloned calves. Isolation of MSC-AF was performed using in vivo ultrasound-guided transvaginal amniocentesis, and MSC-AT were isolated by explant culture. Cellular phenotypic and genotypic characterization by flow cytometry, immunohistochemistry, and RT-PCR were performed, as well as induction in different cell lineages. The NT was performed using MSC-AF and MSC-AT as nuclear donors. The mesenchymal markers of MSC were expressed in bovine MSC-AF and MSC-AT cultures, as evidenced by flow cytometry, immunohistochemistry, and RT-PCR. When induced, these cells differentiated into osteocytes, chondrocytes, and adipocytes. Embryo production was similar between the cell types, and two calves were born. The calf from MSC-AT was born healthy, and this fact opens a new possibility of using this type of cell to produce cloned cattle by NT. PMID:27055630

  4. Rapamycin treatment during in vitro maturation of oocytes improves embryonic development after parthenogenesis and somatic cell nuclear transfer in pigs

    PubMed Central

    Lee, Joohyeong; Park, Jong-Im; Yun, Jung Im; Lee, Yongjin; Yong, Hwanyul; Lee, Seung Tae; Park, Choon-Keun; Hyun, Sang-Hwan; Lee, Geun-Shik

    2015-01-01

    This study was conducted to investigate the effects of rapamycin treatment during in vitro maturation (IVM) on oocyte maturation and embryonic development after parthenogenetic activation (PA) and somatic cell nuclear transfer (SCNT) in pigs. Morphologically good (MGCOCs) and poor oocytes (MPCOCs) were untreated or treated with 1 nM rapamycin during 0-22 h, 22-42 h, or 0-42 h of IVM. Rapamycin had no significant effects on nuclear maturation and blastocyst formation after PA of MGCOCs. Blastocyst formation after PA was significantly increased by rapamycin treatment during 22-42 h and 0-42 h (46.6% and 46.5%, respectively) relative to the control (33.3%) and 0-22 h groups (38.6%) in MPCOCs. In SCNT, blastocyst formation tended to increase in MPCOCs treated with rapamycin during 0-42 h of IVM relative to untreated oocytes (20.3% vs. 14.3%, 0.05 < p < 0.1), while no improvement was observed in MGCOCs. Gene expression analysis revealed that transcript abundance of Beclin 1 and microtubule-associated protein 1 light chain 3 mRNAs was significantly increased in MPCOCs by rapamycin relative to the control. Our results demonstrated that autophagy induction by rapamycin during IVM improved developmental competence of oocytes derived from MPCOCs. PMID:25797293

  5. Transfer of infrared thermography predictive maintenance technologies to Soviet-designed nuclear power plants: experience at Chernobyl

    NASA Astrophysics Data System (ADS)

    Pugh, Ray; Huff, Roy

    1999-03-01

    The importance of infrared (IR) technology and analysis in today's world of predictive maintenance and reliability- centered maintenance cannot be understated. The use of infrared is especially important in facilities that are required to maintain a high degree of equipment reliability because of plant or public safety concerns. As with all maintenance tools, particularly those used in predictive maintenance approaches, training plays a key role in their effectiveness and the benefit gained from their use. This paper details an effort to transfer IR technology to Soviet- designed nuclear power plants in Russia, Ukraine, and Lithuania. Delivery of this technology and post-delivery training activities have been completed recently at the Chornobyl nuclear power plant in Ukraine. Many interesting challenges were encountered during this effort. Hardware procurement and delivery of IR technology to a sensitive country were complicated by United States regulations. Freight and shipping infrastructure and host-country customs policies complicated hardware transport. Training activities were complicated by special hardware, software and training material translation needs, limited communication opportunities, and site logistical concerns. These challenges and others encountered while supplying the Chornobyl plant with state-of-the-art IR technology are described in this paper.

  6. Impact of different sources of donor cells upon the nuclear transfer efficiency in Chinese indigenous Meishan pig.

    PubMed

    Hua, Z; Xu, G; Liu, X; Bi, Y; Xiao, H; Hua, W; Li, L; Zhang, L; Ren, H; Zheng, X

    2016-01-01

    Somatic cell nuclear transfer (SCNT) is currently the most efficient and precise method to generate genetically tailored pig models for both agricultural and biomedical research. However, its efficiency is crucially dependent on the source of nuclear donor cells. In this study, we compared the cloning efficiency by using three lines of donor cells that are derived from fetal, newborn and adult fibroblasts of Chinese indigenous Meishan pig. We showed that cleavage rate and blastocyst formation rate of the reconstructed embryos were not significantly different between the fetal (80.7% and 15.6%) and newborn ear skin (77.5% and 12.3%) fibroblast groups (p>0.05), but in both groups these indices were significantly higher than that found in the adult ear skin (70.5% and 8.8%; p<0.05). Reconstructed embryos derived from fetal, newborn, and adult ear skin fibroblasts were transferred to four surrogates, respectively. For the fetal, newborn, and adult ear skin fibroblasts, the number of pregnancies were two (50.0%), two (50.0%), and one (25.0%), respectively, and the number of deliveries were two (50.0%), one (25.0%), and zero (0.0%), respectively. Seven and two cloned piglets were obtained from the fetal and newborn ear skin fibroblasts respectively, while no piglets were obtained from the adult ear skin fibroblasts. Two cloned piglets from the newborn ear skin fibroblasts died shortly after birth because of neonatal asphyxia caused by dystocia. The birth weights of the piglets derived from the fetal and newborn ear skin fibroblasts were 1230.5 and 1310.0 g, respectively, which were statistically insignificant (p>0.05), but both were significantly higher than that of the control groups (p<0.05). Microsatellite analyses demonstrated that the genotypes of all cloned piglets were identical to their donor cells. Therefore, cloned pigs were successfully produced using two sources of donor cells isolated from the fetal and newborn ear skin fibroblasts of Meishan piglet, and

  7. Structure of the β2-α2 loop and interspecies prion transmission

    PubMed Central

    Bett, Cyrus; Fernández-Borges, Natalia; Kurt, Timothy D.; Lucero, Melanie; Nilsson, K. Peter R.; Castilla, Joaquín; Sigurdson, Christina J.

    2012-01-01

    Prions are misfolded, aggregated conformers of the prion protein that can be transmitted between species. The precise determinants of interspecies transmission remain unclear, although structural similarity between the infectious prion and host prion protein is required for efficient conversion to the misfolded conformer. The β2-α2 loop region of endogenous prion protein, PrPC, has been implicated in barriers to prion transmission. We recently discovered that conversion was efficient when incoming and host prion proteins had similar β2-α2 loop structures; however, the roles of primary vs. secondary structural homology could not be distinguished. Here we uncouple the effect of primary and secondary structural homology of the β2-α2 loop on prion conversion. We inoculated prions from animals having a disordered or an ordered β2-α2 loop into mice having a disordered loop or an ordered loop due to a single residue substitution (D167S). We found that prion conversion was driven by a homologous primary structure and occurred independently of a homologous secondary structure. Similarly, cell-free conversion using PrPC from mice with disordered or ordered loops and prions from 5 species correlated with primary but not secondary structural homology of the loop. Thus, our findings support a model in which efficient interspecies prion conversion is determined by small stretches of the primary sequence rather than the secondary structure of PrP.—Bett, C., Fernández-Borges, N., Kurt, T. D., Lucero, M., Nilsson, K. P. R., Castilla, J., Sigurdson, C. J. Structure of the β2-α2 loop and interspecies prion transmission. PMID:22490928

  8. Interspecies chimeric complementation for the generation of functional human tissues and organs in large animal hosts.

    PubMed

    Wu, Jun; Izpisua Belmonte, Juan Carlos

    2016-06-01

    The past decade's rapid progress in human pluripotent stem cell (hPSC) research has generated hope for meeting the rising demand of organ donation, which remains the only effective cure for end-stage organ failure, a major cause of death worldwide. Despite the potential, generation of transplantable organs from hPSCs using in vitro differentiation is far-fetched. An in vivo interspecies chimeric complementation strategy relying on chimeric-competent hPSCs and zygote genome editing provides an auspicious alternative for providing unlimited organ source for transplantation. PMID:26820411

  9. Heat Transfer Salts for Nuclear Reactor Systems - Chemistry Control, Corrosion Mitigation, and Modeling

    SciTech Connect

    Anderson, Mark; Sridharan, Kumar; Morgan, Dane; Peterson, Per; Calderoni, Pattrick; Scheele, Randall; Casekka, Andrew; McNamara, Bruce

    2015-01-22

    The concept of a molten salt reactor has existed for nearly sixty years. Previously all work was done during a large collaborative effort at Oak Ridge National Laboratory, culminating in a research reactor which operated for 15,000 hours without major error. This technical success has garnished interest in modern, high temperature, reactor schemes. Research using molten fluoride salts for nuclear applications requires a steady supply of high grade molten salts. There is no bulk supplier of research grade fluoride salts in the world, so a facility which could provide all the salt needed for testing at the University of Wisconsin had to be produced. Two salt purification devices were made for this purpose, a large scale purifier, and a small scale purifier, each designed to clean the salts from impurities and reduce their corrosion potential. As of now, the small scale has performed with flibe salt, hydrogen, and hydrogen fluoride, yielding clean salt. This salt is currently being used in corrosion testing facilities at the Massachusetts Institute of Technology and the University of Wisconsin. Working with the beryllium based salts requires extensive safety measures and health monitoring to prevent the development of acute or chronic beryllium disease, two pulmonary diseases created by an allergic reaction to beryllium in the lungs. Extensive health monitoring, engineering controls, and environment monitoring had to be set up with the University of Wisconsin department of Environment, Health and Safety. The hydrogen fluoride required for purification was also an extreme health hazard requiring thoughtful planning and execution. These dangers have made research a slow and tedious process. Simple processes, such as chemical handling and clean-up, can take large amounts of ingenuity and time. Other work has complemented the experimental research at Wisconsin to advance high temperature reactor goals. Modeling work has been performed in house to re

  10. Genetic evidence of interspecies introgression of mitochondrial genomes between Trichinella spiralis and Trichinella britovi under natural conditions.

    PubMed

    Franssen, Frits; Bilska-Zając, Ewa; Deksne, Gunita; Sprong, Hein; Pozio, Edoardo; Rosenthal, Benjamin; Rozycki, Mirek; van der Giessen, Joke

    2015-12-01

    Trichinellosis is a zoonotic disease caused by Trichinella muscle larvae (ML) through ingestion of raw or undercooked meat. To date, 12 taxa are recognized in this genus, of which four are circulating in Europe (Trichinella spiralis, Trichinella nativa, Trichinella britovi and Trichinella pseudospiralis). T. spiralis and T. britovi circulate in European wildlife and occur simultaneously in the same host species. The possibility of hybrid formation between T. britovi and T. spiralis has hardly been addressed and so far, results of experimental hybridisation attempts between T. britovi and T. spiralis are inconclusive. The aim of the present study was to analyse molecular polymorphisms of single T. spiralis and T. britovi ML from natural infections based on nuclear 5S rDNA intergenic spacer region (5S rDNA-ISR) and mitochondrial cytochrome c oxidase 1 (CO1) gene sequences. Six haplotypes of the 5S rDNA intergenic spacer region (5S rDNA-ISR) and 14 of the cytochrome c oxidase 1 (CO1) gene were demonstrated in 89 individual T. britovi ML from Latvia and Poland. In contrast, only two haplotypes were observed at both 5S rDNA-ISR and CO1 of 57 individual T. spiralis ML from Polish wild boar and red foxes. Moreover, this study demonstrates hybridisation in eight individual ML between T. britovi and T. spiralis under natural conditions in four Polish wild boar and two red foxes, revealed by combining 5S rDNA-ISR and CO1 sequence information of individual Trichinella ML. To our knowledge, this is the first report of interspecies hybridisation between T. spiralis and T. britovi under field conditions. PMID:26458526

  11. Effect of radiocesium transfer on ambient dose rate in forest environments affected by the Fukushima Nuclear Power Plant accident

    NASA Astrophysics Data System (ADS)

    Kato, H.

    2015-12-01

    We investigated the transfer of canopy-intercepted radiocesium to the forest floor during 3 years following the Fukushima Daiichi Nuclear Power Plant accident. The cesium-137 (Cs-137) contents in throughfall, stemflow, and litterfall were monitored in two coniferous stands (plantation of Japanese cedar) and a deciduous broad-leaved forest stand (Japanese oak with red pine). We also measured the ambient dose rate (ADR) at different heights in the forest using a survey meter and a portable Ge gamma-ray detector. Total Cs-137 deposition flux from the canopy to forest floor for the mature cedar, young cedar, and the mixed broad-leaved stands were 166 kBq/m2, 174 kBq/m2, and 60 kBq/m2, respectively. These values correspond to 38%, 40% and 13% of total atmospheric input after the accident. The ambient dose rate in forest exhibited height dependency and its vertical distribution varied with forest type and stand age. The ambient dose rate showed an exponential decrease with time for all the forest sites, however the decreasing trend differed depending on the height of dose measurement and forest type. The ambient dose rate at the canopy (approx. 10 m-height) decreased faster than that expected from physical decay of the two radiocesium isotopes, whereas those at the forest floor varied between the three forest stands. The radiocesium deposition via throughfall seemed to increase ambient dose rate during the first 200 days after the accident, however there was no clear relationship between litterfall and ambient dose rate since 400 days after the accident. These data suggested that the ambient dose rate in forest environment varied both spatially and temporally reflecting the transfer of radiocesium from canopy to forest floor. However, further monitoring investigation and analysis are required to determine the effect of litterfall on long-term trend of ambient dose rate in forest environments.

  12. High-resolution imaging of magnetisation transfer and nuclear Overhauser effect in the human visual cortex at 7 T.

    PubMed

    Mougin, Olivier; Clemence, Matthew; Peters, Andrew; Pitiot, Alain; Gowland, Penny

    2013-11-01

    The aim of this study was to optimise a pulse sequence for high-resolution imaging sensitive to the effects of conventional macromolecular magnetisation transfer (MT(m)) and nuclear Overhauser enhancement (NOE), and to use it to investigate variations in these parameters across the cerebral cortex. A high-spatial-resolution magnetisation transfer-prepared turbo field echo (MT-TFE) sequence was designed to have high sensitivity to MT(m) and NOE effects, whilst being robust to B0 and B1 inhomogeneities, and producing a good point spread function across the cortex. This was achieved by optimising the saturation and imaging components of the sequence using simulations based on the Bloch equations, including exchange and an image simulator. This was used to study variations in these parameters across the cortex. Using the sequence designed to be sensitive to NOE and MT(m), a variation in signals corresponding to a variation in MT(m) and NOE across the cortex, consistent with a reduction in myelination from the white matter surface to the pial surface of the cortex, was observed. In regions in which the stria was visible on T2*-weighted images, it could also be detected in signals sensitive to MT(m) and NOE. There was greater variation in signals sensitive to NOE, suggesting that the NOE signal is more sensitive to myelination. A sequence has been designed to image variations in MT(m) and NOE at high spatial resolution and has been used to investigate variations in contrast in these parameters across the cortex. PMID:23801569

  13. Differences during the first lactation between cows cloned by somatic cell nuclear transfer and noncloned cows.

    PubMed

    Montazer-Torbati, F; Boutinaud, M; Brun, N; Richard, C; Neveu, A; Jaffrézic, F; Laloë, D; LeBourhis, D; Nguyen, M; Chadi, S; Jammes, H; Renard, J-P; Chat, S; Boukadiri, A; Devinoy, E

    2016-06-01

    Lactation performance is dependent on both the genetic characteristics and the environmental conditions surrounding lactating cows. However, individual variations can still be observed within a given breed under similar environmental conditions. The role of the environment between birth and lactation could be better appreciated in cloned cows, which are presumed to be genetically identical, but differences in lactation performance between cloned and noncloned cows first need to be clearly evaluated. Conflicting results have been described in the literature, so our aim was to clarify this situation. Nine cloned Prim' Holstein cows were produced by the transfer of nuclei from a single fibroblast cell line after cell fusion with enucleated oocytes. The cloned cows and 9 noncloned counterparts were raised under similar conditions. Milk production and composition were recorded monthly from calving until 200d in milk. At 67d in milk, biopsies were sampled from the rear quarter of the udder, their mammary epithelial cell content was evaluated, and mammary cell renewal, RNA, and DNA were then analyzed in relevant samples. The results showed that milk production did not differ significantly between cloned and noncloned cows, but milk protein and fat contents were less variable in cloned cows. Furthermore, milk fat yield and contents were lower in cloned cows during early lactation. At around 67 DIM, milk fat and protein yields, as well as milk fat, protein, and lactose contents, were also lower in cloned cows. These lower yields could be linked to the higher apoptotic rate observed in cloned cows. Apoptosis is triggered by insulin-like factor growth binding protein 5 (IGFBP5) and plasminogen activator inhibitor (PAI), which both interact with CSN1S2. During our experiments, CSN1S2 transcript levels were lower in the mammary gland of cloned cows. The mammary cell apoptotic rate observed in cloned cows may have been related to the higher levels of DNA (cytosine-5

  14. Interspecies competition triggers virulence and mutability in Candida albicans–Pseudomonas aeruginosa mixed biofilms

    PubMed Central

    Trejo-Hernández, Abigail; Andrade-Domínguez, Andrés; Hernández, Magdalena; Encarnación, Sergio

    2014-01-01

    Inter-kingdom and interspecies interactions are ubiquitous in nature and are important for the survival of species and ecological balance. The investigation of microbe-microbe interactions is essential for understanding the in vivo activities of commensal and pathogenic microorganisms. Candida albicans, a polymorphic fungus, and Pseudomonas aeruginosa, a Gram-negative bacterium, are two opportunistic pathogens that interact in various polymicrobial infections in humans. To determine how P. aeruginosa affects the physiology of C. albicans and vice versa, we compared the proteomes of each species in mixed biofilms versus single-species biofilms. In addition, extracellular proteins were analyzed. We observed that, in mixed biofilms, both species showed differential expression of virulence proteins, multidrug resistance-associated proteins, proteases and cell defense, stress and iron-regulated proteins. Furthermore, in mixed biofilms, both species displayed an increase in mutability compared with monospecific biofilms. This characteristic was correlated with the downregulation of enzymes conferring protection against DNA oxidation. In mixed biofilms, P. aeruginosa regulates its production of various molecules involved in quorum sensing and induces the production of virulence factors (pyoverdine, rhamnolipids and pyocyanin), which are major contributors to the ability of this bacterium to cause disease. Overall, our results indicate that interspecies competition between these opportunistic pathogens enhances the production of virulence factors and increases mutability and thus can alter the course of host-pathogen interactions in polymicrobial infections. PMID:24739628

  15. Interspecies extrapolation for mammals and birds: What`s a risk assessor to do?

    SciTech Connect

    Norton, S.R.; Rhomberg, L.

    1995-12-31

    Ecological risk assessors are often faced with the need to extrapolate laboratory data on a particular species to another species of interest. For aquatic organisms, an extensive database is available that has been used to develop empirical intertaxa extrapolation factors. For birds and mammals, however, such a database does not exist. This presentation explores the strengths and limitations of using knowledge of allometric scaling to address issues of interspecies differences in toxic response. In particular, the authors focus on approaches for oral exposure. Most approaches to interspecies extrapolation begin with implicit or explicit assumptions about how to express equivalent doses for different body sizes. It is in these calculations that knowledge of allometric scaling has its greatest applicability. Options include adjusting dose for equivalent organ weights (i.e., approximately BW{sup 1}), equivalent surface area (i.e., approximately BW{sup 2/3}), or equivalent metabolic rate (i.e., approximately BW{sup 3/4}). The authors will discuss the basis for each of these options, precedents for their use, and implications for analyzing ecotoxicological data.

  16. Development of quantitative interspecies toxicity relationship modeling of chemicals to fish.

    PubMed

    Fatemi, M H; Mousa Shahroudi, E; Amini, Z

    2015-09-01

    In this work, quantitative interspecies-toxicity relationship methodologies were used to improve the prediction power of interspecies toxicity model. The most relevant descriptors selected by stepwise multiple linear regressions and toxicity of chemical to Daphnia magna were used to predict the toxicities of chemicals to fish. Modeling methods that were used for developing linear and nonlinear models were multiple linear regression (MLR), random forest (RF), artificial neural network (ANN) and support vector machine (SVM). The obtained results indicate the superiority of SVM model over other models. Robustness and reliability of the constructed SVM model were evaluated by using the leave-one-out cross-validation method (Q(2)=0.69, SPRESS=0.822) and Y-randomization test (R(2)=0.268 for 30 trail). Furthermore, the chemical applicability domains of these models were determined via leverage approach. The developed SVM model was used for the prediction of toxicity of 46 compounds that their experimental toxicities to a fish were not being reported earlier from their toxicities to D. magna and relevant molecular descriptors. PMID:26002421

  17. Interspecies competition triggers virulence and mutability in Candida albicans-Pseudomonas aeruginosa mixed biofilms.

    PubMed

    Trejo-Hernández, Abigail; Andrade-Domínguez, Andrés; Hernández, Magdalena; Encarnación, Sergio

    2014-10-01

    Inter-kingdom and interspecies interactions are ubiquitous in nature and are important for the survival of species and ecological balance. The investigation of microbe-microbe interactions is essential for understanding the in vivo activities of commensal and pathogenic microorganisms. Candida albicans, a polymorphic fungus, and Pseudomonas aeruginosa, a Gram-negative bacterium, are two opportunistic pathogens that interact in various polymicrobial infections in humans. To determine how P. aeruginosa affects the physiology of C. albicans and vice versa, we compared the proteomes of each species in mixed biofilms versus single-species biofilms. In addition, extracellular proteins were analyzed. We observed that, in mixed biofilms, both species showed differential expression of virulence proteins, multidrug resistance-associated proteins, proteases and cell defense, stress and iron-regulated proteins. Furthermore, in mixed biofilms, both species displayed an increase in mutability compared with monospecific biofilms. This characteristic was correlated with the downregulation of enzymes conferring protection against DNA oxidation. In mixed biofilms, P. aeruginosa regulates its production of various molecules involved in quorum sensing and induces the production of virulence factors (pyoverdine, rhamnolipids and pyocyanin), which are major contributors to the ability of this bacterium to cause disease. Overall, our results indicate that interspecies competition between these opportunistic pathogens enhances the production of virulence factors and increases mutability and thus can alter the course of host-pathogen interactions in polymicrobial infections. PMID:24739628

  18. Automated aural classification used for inter-species discrimination of cetaceans.

    PubMed

    Binder, Carolyn M; Hines, Paul C

    2014-04-01

    Passive acoustic methods are in widespread use to detect and classify cetacean species; however, passive acoustic systems often suffer from large false detection rates resulting from numerous transient sources. To reduce the acoustic analyst workload, automatic recognition methods may be implemented in a two-stage process. First, a general automatic detector is implemented that produces many detections to ensure cetacean presence is noted. Then an automatic classifier is used to significantly reduce the number of false detections and classify the cetacean species. This process requires development of a robust classifier capable of performing inter-species classification. Because human analysts can aurally discriminate species, an automated aural classifier that uses perceptual signal features was tested on a cetacean data set. The classifier successfully discriminated between four species of cetaceans-bowhead, humpback, North Atlantic right, and sperm whales-with 85% accuracy. It also performed well (100% accuracy) for discriminating sperm whale clicks from right whale gunshots. An accuracy of 92% and area under the receiver operating characteristic curve of 0.97 were obtained for the relatively challenging bowhead and humpback recognition case. These results demonstrated that the perceptual features employed by the aural classifier provided powerful discrimination cues for inter-species classification of cetaceans. PMID:25235008

  19. A RANKL mutant used as an inter-species vaccine for efficient immunotherapy of osteoporosis

    PubMed Central

    Liu, Changzhen; Zhao, Yunfeng; He, Wen; Wang, Wei; Chen, Yuan; Zhang, Shiqian; Ma, Yijing; Gohda, Jin; Ishida, Takaomi; Walter, Thomas S.; Owens, Raymond J.; Stuart, David I.; Ren, Jingshan; Gao, Bin

    2015-01-01

    Anti-cytokine therapeutic antibodies have been demonstrated to be effective in the treatment of several auto-immune disorders. However, The problems in antibody manufacture and the immunogenicity caused by multiple doses of antibodies inspire people to use auto-cytokine as immunogen to induce anti-cytokine antibodies. Nevertheless, the tolerance for inducing immune response against self-antigen has hindered the wide application of the strategy. To overcome the tolerance, here we proposed a strategy using the inter-species cytokine as immunogen for active immunization (TISCAI) to induce anti-cytokine antibody. As a proof of concept, an inter-species cytokine RANKL was successfully used as immunogen to induce anti-RANKL immune response. Furthermore, to prevent undesirable side-effects, the human RANKL was mutated based on the crystal structure of the complex of human RANKL and its rodent counterpart receptor RANK. We found, the antibodies produced blocked the osteoclast development in vitro and osteoporosis in OVX rat models. The results demonstrated this strategy adopted is very useful for general anti-cytokine immunotherapy for different diseases settings. PMID:26412210

  20. Morphological and molecular characterization of yellow oyster mushroom, Pleurotus citrinopileatus, hybrids obtained by interspecies mating.

    PubMed

    Rosnina, A G; Tan, Yee Shin; Abdullah, Noorlidah; Vikineswary, S

    2016-02-01

    Pleurotus citrinopileatus (yellow oyster mushroom) has an attractive shape and yellow colour but the fragile texture complicates packaging, and its strong aroma is unappealing to consumers. This study aimed to improve the characteristics and yield of P. citrinopileatus by interspecies mating between monokaryotic cultures of P. citrinopileatus and P. pulmonarius. Ten monokaryon cultures of the parental lines were crossed in all combinations to obtain hybrids. Eleven compatible mating pairs were obtained and cultivated to observe their sporophore morphology and yield. The selected hybrid, i.e. P1xC9, was beige in colour while hybrid P3xC8 was yellow in colour. Their sporophores had less offensive aroma, improved texture and higher yield. The DNA sequences of these hybrids were found to be in the same clade as the P. citrinopileatus parent with a bootstrap value of 99%. High bootstrap values indicate high genetic homology between hybrids and the P. citrinopileatus parent. The biological efficiencies of these hybrids P1xC9 (70.97%) and P3xC8 (52.14%) were also higher than the P. citrinopileatus parent (35.63%). Interspecies hybrids obtained by this mating technique can lead to better strains of mushrooms for genetic improvement of the Pleurotus species. PMID:26745978

  1. Interspecies Ion Diffusion Studies using DT, DT(3He), and DT(H) Implosions

    NASA Astrophysics Data System (ADS)

    Kim, Y.; Herrmann, H. W.; Schmitt, M. J.; Kagan, G.; McEvoy, A. M.; Hoffman, N. M.; Gales, S.; Leatherland, A.; Gatu Johnson, M.; Frenje, J.; Glevov, V. Yu; Forrest, C.

    2015-11-01

    Anomalous ICF yield degradation has been observed from gas fills containing mixtures (i.e., D(3He), DT(3He), D(Ar), and even DT). Interspecies ion diffusion theory has been suggested as a possible cause resulting from gradient-driven diffusion (i.e., pressure, electric potential, and temperature) which forces lower mass ions away from core and higher mass ions toward core. The theory predicts hydrogen addition to deuterium or tritium should result in increased yield compared to expected yield, which is opposite to 3He addition. At Omega laser facility, we have tested hydro-equivalent fills of DT, DT(3He), and DT(H) with the assumption that same fuel mass and particle pressure will provide identical convergence. Preliminary results verify a factor of 2 yield reduction relative to scaling when 3He added to DT. At DT(H) case, however, no significant yield degradation or a slight yield enhancement was observed which agrees with the interspecies ion diffusion theory. Detailed experiment results and simulation are needed to confirm the initial observation.

  2. Predicting passive and active tissue:plasma partition coefficients: interindividual and interspecies variability.

    PubMed

    Ruark, Christopher D; Hack, C Eric; Robinson, Peter J; Mahle, Deirdre A; Gearhart, Jeffery M

    2014-07-01

    A mechanistic tissue composition model incorporating passive and active transport for the prediction of steady-state tissue:plasma partition coefficients (K(t:pl)) of chemicals in multiple mammalian species was used to assess interindividual and interspecies variability. This approach predicts K(t:pl) using chemical lipophilicity, pKa, phospholipid membrane binding, and the unbound plasma fraction, together with tissue fractions of water, neutral lipids, neutral and acidic phospholipids, proteins, and pH. Active transport K(t:pl) is predicted using Michaelis-Menten transport parameters. Species-specific biological properties were identified from 126 peer reviewed journal articles, listed in the Supporting Information, for mouse, rat, guinea pig, rabbit, beagle dog, pig, monkey, and human species. Means and coefficients of variation for biological properties were used in a Monte Carlo analysis to assess variability. The results show K(t:pl) interspecies variability for the brain, fat, heart, kidney, liver, lung, muscle, red blood cell, skin, and spleen, but uncertainty in the estimates obscured some differences. Compounds undergoing active transport are shown to have concentration-dependent K(t:pl). This tissue composition-based mechanistic model can be used to predict K(t:pl) for organic chemicals across eight species and 10 tissues, and can be an important component in drug development when scaling K(t:pl) from animal models to humans. PMID:24832575

  3. Generation of porcine fetal fibroblasts expressing the tetracycline-inducible Cas9 gene by somatic cell nuclear transfer.

    PubMed

    Liu, Guoqian; Liu, Kai; Wei, Hengxi; Li, Li; Zhang, Shouquan

    2016-09-01

    Cas9 endonuclease, from so-called clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated (Cas) systems of Streptococcus pyogenes, type II functions as an RNA-guided endonuclease and edits the genomes of prokaryotic and eukaryotic organisms, including deletion and insertion by DNA double‑stranded break repair mechanisms. In previous studies, it was observed that Cas9, with a genome‑scale lentiviral single‑guide RNA library, could be applied to a loss‑of‑function genetic screen, although the loss‑of‑function genes have yet to be verified in vitro and this approach has not been used in porcine cells. Based on these observations, lentiviral Cas9 was used to infect porcine primary fibroblasts to achieve cell colonies carrying Cas9 endonuclease. Subsequently, porcine fetal fibroblasts expressing the tetracycline‑inducible Cas9 gene were generated by somatic cell nuclear transfer, and three 30 day transgenic porcine fetal fibroblasts (PFFs) were obtained. Polymerase chain reaction (PCR), reverse transcription‑PCR and western blot analysis indicated that the PFFs were Cas9‑positive. In addition, one of the three integrations was located near to known functional genes in the PFF1 cell line, whereas neither of the integrations was located in the PFF1 or PFF2 cell lines. It was hypothesized that these transgenic PFFs may be useful for conditional genomic editing in pigs, and for generating ideal modified porcine models. PMID:27430306

  4. Histone Demethylase Expression Enhances Human Somatic Cell Nuclear Transfer Efficiency and Promotes Derivation of Pluripotent Stem Cells.

    PubMed

    Chung, Young Gie; Matoba, Shogo; Liu, Yuting; Eum, Jin Hee; Lu, Falong; Jiang, Wei; Lee, Jeoung Eun; Sepilian, Vicken; Cha, Kwang Yul; Lee, Dong Ryul; Zhang, Yi

    2015-12-01

    The extremely low efficiency of human embryonic stem cell (hESC) derivation using somatic cell nuclear transfer (SCNT) limits its potential application. Blastocyst formation from human SCNT embryos occurs at a low rate and with only some oocyte donors. We previously showed in mice that reduction of histone H3 lysine 9 trimethylation (H3K9me3) through ectopic expression of the H3K9me3 demethylase Kdm4d greatly improves SCNT embryo development. Here we show that overexpression of a related H3K9me3 demethylase KDM4A improves human SCNT, and that, as in mice, H3K9me3 in the human somatic cell genome is an SCNT reprogramming barrier. Overexpression of KDM4A significantly improves the blastocyst formation rate in human SCNT embryos by facilitating transcriptional reprogramming, allowing efficient derivation of SCNT-derived ESCs using adult Age-related Macular Degeneration (AMD) patient somatic nuclei donors. This conserved mechanistic insight has potential applications for improving SCNT in a variety of contexts, including regenerative medicine. PMID:26526725

  5. Dynamic aspects of antibody:oligosaccharide complexes characterized by molecular dynamics simulations and saturation transfer difference nuclear magnetic resonance.

    PubMed

    Theillet, François-Xavier; Frank, Martin; Vulliez-Le Normand, Brigitte; Simenel, Catherine; Hoos, Sylviane; Chaffotte, Alain; Bélot, Frédéric; Guerreiro, Catherine; Nato, Farida; Phalipon, Armelle; Mulard, Laurence A; Delepierre, Muriel

    2011-12-01

    Carbohydrates are likely to maintain significant conformational flexibility in antibody (Ab):carbohydrate complexes. As demonstrated herein for the protective monoclonal Ab (mAb) F22-4 recognizing the Shigella flexneri 2a O-antigen (O-Ag) and numerous synthetic oligosaccharide fragments thereof, the combination of molecular dynamics simulations and nuclear magnetic resonance saturation transfer difference experiments, supported by physicochemical analysis, allows us to determine the binding epitope and its various contributions to affinity without using any modified oligosaccharides. Moreover, the methods used provide insights into ligand flexibility in the complex, thus enabling a better understanding of the Ab affinities observed for a representative set of synthetic O-Ag fragments. Additionally, these complementary pieces of information give evidence to the ability of the studied mAb to recognize internal as well as terminal epitopes of its cognate polysaccharide antigen. Hence, we show that an appropriate combination of computational and experimental methods provides a basis to explore carbohydrate functional mimicry and receptor binding. The strategy may facilitate the design of either ligands or carbohydrate recognition domains, according to needed improvements of the natural carbohydrate:receptor properties. PMID:21610193

  6. Stochastic anomaly of methylome but persistent SRY hypermethylation in disorder of sex development in canine somatic cell nuclear transfer

    PubMed Central

    Jeong, Young-Hee; Lu, Hanlin; Park, Chi-Hun; Li, Meiyan; Luo, Huijuan; Kim, Joung Joo; Liu, Siyang; Ko, Kyeong Hee; Huang, Shujia; Hwang, In Sung; Kang, Mi Na; Gong, Desheng; Park, Kang Bae; Choi, Eun Ji; Park, Jung Hyun; Jeong, Yeon Woo; Moon, Changjong; Hyun, Sang-Hwan; Kim, Nam Hyung; Jeung, Eui-Bae; Yang, Huanming; Hwang, Woo Suk; Gao, Fei

    2016-01-01

    Somatic cell nuclear transfer (SCNT) provides an excellent model for studying epigenomic reprogramming during mammalian development. We mapped the whole genome and whole methylome for potential anomalies of mutations or epimutations in SCNT-generated dogs with XY chromosomal sex but complete gonadal dysgenesis, which is classified as 78, XY disorder of sex development (DSD). Whole genome sequencing revealed no potential genomic variations that could explain the pathogenesis of DSD. However, extensive but stochastic anomalies of genome-wide DNA methylation were discovered in these SCNT DSD dogs. Persistent abnormal hypermethylation of the SRY gene was observed together with its down-regulated mRNA and protein expression. Failure of SRY expression due to hypermethylation was further correlated with silencing of a serial of testis determining genes, including SOX9, SF1, SOX8, AMH and DMRT1 in an early embryonic development stage at E34 in the XYDSD gonad, and high activation of the female specific genes, including FOXL2, RSPO1, CYP19A1, WNT4, ERα and ERβ, after one postnatal year in the ovotestis. Our results demonstrate that incomplete demethylation on the SRY gene is the driving cause of XYDSD in these XY DSD dogs, indicating a central role of epigenetic regulation in sex determination. PMID:27501986

  7. Trichostatin A specifically improves the aberrant expression of transcription factor genes in embryos produced by somatic cell nuclear transfer

    PubMed Central

    Inoue, Kimiko; Oikawa, Mami; Kamimura, Satoshi; Ogonuki, Narumi; Nakamura, Toshinobu; Nakano, Toru; Abe, Kuniya; Ogura, Atsuo

    2015-01-01

    Although mammalian cloning by somatic cell nuclear transfer (SCNT) has been established in various species, the low developmental efficiency has hampered its practical applications. Treatment of SCNT-derived embryos with histone deacetylase (HDAC) inhibitors can improve their development, but the underlying mechanism is still unclear. To address this question, we analysed gene expression profiles of SCNT-derived 2-cell mouse embryos treated with trichostatin A (TSA), a potent HDAC inhibitor that is best used for mouse cloning. Unexpectedly, TSA had no effect on the numbers of aberrantly expressed genes or the overall gene expression pattern in the embryos. However, in-depth investigation by gene ontology and functional analyses revealed that TSA treatment specifically improved the expression of a small subset of genes encoding transcription factors and their regulatory factors, suggesting their positive involvement in de novo RNA synthesis. Indeed, introduction of one of such transcription factors, Spi-C, into the embryos at least partially mimicked the TSA-induced improvement in embryonic development by activating gene networks associated with transcriptional regulation. Thus, the effects of TSA treatment on embryonic gene expression did not seem to be stochastic, but more specific than expected, targeting genes that direct development and trigger zygotic genome activation at the 2-cell stage. PMID:25974394

  8. Relationships of survival time, productivity and cause of death with telomere lengths of cows produced by somatic cell nuclear transfer.

    PubMed

    Konishi, Kazuyuki; Yonai, Miharu; Kaneyama, Kanako; Ito, Satoshi; Matsuda, Hideo; Yoshioka, Hajime; Nagai, Takashi; Imai, Kei

    2011-10-01

    The reproductive ability, milk-producing capacity, survival time and relationships of these parameters with telomere length were investigated in 4 groups of cows produced by somatic cell nuclear transfer (SCNT). Each group was produced using the same donor cells (6 Holstein (1H), 3 Holstein (2H), 4 Jersey (1J) and 5 Japanese Black (1B) cows). As controls, 47 Holstein cows produced by artificial insemination were used. The SCNT cows were artificially inseminated, and multiple deliveries were performed after successive rounds of breeding and conception. No correlation was observed between the telomere length and survival time in the SCNT cows. Causes of death of SCNT cows included accidents, accident-associated infections, inappropriate management, acute mastitis and hypocalcemia. The lifetime productivity of SCNT cows was superior to those of the controls and cell donor cows. All SCNT beef cows with a relatively light burden of lactation remained alive and showed significantly prolonged survival time compared with the cows in the SCNT dairy breeds. These results suggest that the lifetime productivity of SCNT cows was favorable, and their survival time was more strongly influenced by environmental burdens, such as pregnancy, delivery, lactation and feeding management, than by the telomere length. PMID:21666348

  9. Analysis of ENPP2 in the Uterine Endometrium of Pigs Carrying Somatic Cell Nuclear Transfer Cloned Embryos

    PubMed Central

    Seo, Heewon; Choi, Yohan; Yu, Inkyu; Shim, Jangsoo; Lee, Chang-Kyu; Hyun, Sang-Hwan; Lee, Eunsong; Ka, Hakhyun

    2013-01-01

    Somatic cell nuclear transfer (SCNT) is a useful tool for animal cloning, but the efficiency of producing viable offspring by SCNT is very low. To improve this efficiency in the production of cloned pigs, it is critical to understand the interactions between uterine function and cloned embryos during implantation. Lysophosphatidic acid (LPA) is a lipid mediator that plays an important role in the establishment of pregnancy in pigs; however, LPA production in the uterine endometrium of pigs carrying SCNT-cloned conceptuses has not been determined. Therefore, we investigated expression of ENPP2, an LPA-generating enzyme, in the uterine endometrium of gilts with conceptuses derived from SCNT during the implantation period. Uterine endometrial tissue and uterine flushing were obtained from gilts carrying SCNT-derived conceptuses and from gilts carrying conceptuses resulting from natural mating on d 12 of pregnancy. Our results demonstrated no difference in the level of ENPP2 mRNA expression in the uterine endometrium between gilts carrying SCNT-derived conceptuses and gilts carrying naturally-conceived conceptuses, but secretion of ENPP2 protein into the uterine lumen did decrease significantly in pigs with SCNT-derived conceptuses. These results indicate that expression and secretion of ENPP2, which are critical for appropriate LPA production and successful pregnancy, are dysregulated in the uterine endometrium of pigs carrying SCNT-derived conceptuses. PMID:25049907

  10. Improved Cloning Efficiency and Developmental Potential in Bovine Somatic Cell Nuclear Transfer with the Oosight Imaging System

    PubMed Central

    Park, Min Jee; Park, Hyo Young; Noh, Eun Ji; Noh, Eun Hyung; Park, Kyoung Sik; Lee, Jun Beom; Jeong, Chang Jin; Riu, Key Zung

    2012-01-01

    Abstract In somatic cell nuclear transfer (SCNT) procedures, exquisite enucleation of the recipient oocyte is critical to cloning efficiency. The purpose of this study was to compare the effects of two enucleation systems, Hoechst staining and UV irradiation (hereafter, irradiation group) and Oosight imaging (hereafter, Oosight group), on the in vitro production of bovine SCNT embryos. In the Oosight group, the apoptotic index (2.8±0.5 vs. 7.3±1.2) was lower, and the fusion rate (75.6% vs. 62.9%), cleavage rate (78.0% vs. 63.7%), blastocyst rate (40.2% vs. 29.2%), and total cell number (128.3±4.8 vs. 112.2±7.6) were higher than those in the irradiation group (all p<0.05). The overall efficiency after SCNT was twice as high in the Oosight group as that in the irradiation group (p<0.05). The relative mRNA expression levels of Oct4, Nanog, Interferon-tau, and Dnmt3A were higher and those of Caspase-3 and Hsp70 were lower in the Oosight group compared with the irradiation group (p<0.05). This is the first report to show the positive effect of the Oosight imaging system on molecular gene expression in the SCNT embryo. The Oosight imaging system may become the preferred choice for enucleation because it is less detrimental to the developmental potential of bovine SCNT embryos. PMID:22816525

  11. Stochastic anomaly of methylome but persistent SRY hypermethylation in disorder of sex development in canine somatic cell nuclear transfer.

    PubMed

    Jeong, Young-Hee; Lu, Hanlin; Park, Chi-Hun; Li, Meiyan; Luo, Huijuan; Kim, Joung Joo; Liu, Siyang; Ko, Kyeong Hee; Huang, Shujia; Hwang, In Sung; Kang, Mi Na; Gong, Desheng; Park, Kang Bae; Choi, Eun Ji; Park, Jung Hyun; Jeong, Yeon Woo; Moon, Changjong; Hyun, Sang-Hwan; Kim, Nam Hyung; Jeung, Eui-Bae; Yang, Huanming; Hwang, Woo Suk; Gao, Fei

    2016-01-01

    Somatic cell nuclear transfer (SCNT) provides an excellent model for studying epigenomic reprogramming during mammalian development. We mapped the whole genome and whole methylome for potential anomalies of mutations or epimutations in SCNT-generated dogs with XY chromosomal sex but complete gonadal dysgenesis, which is classified as 78, XY disorder of sex development (DSD). Whole genome sequencing revealed no potential genomic variations that could explain the pathogenesis of DSD. However, extensive but stochastic anomalies of genome-wide DNA methylation were discovered in these SCNT DSD dogs. Persistent abnormal hypermethylation of the SRY gene was observed together with its down-regulated mRNA and protein expression. Failure of SRY expression due to hypermethylation was further correlated with silencing of a serial of testis determining genes, including SOX9, SF1, SOX8, AMH and DMRT1 in an early embryonic development stage at E34 in the XY(DSD) gonad, and high activation of the female specific genes, including FOXL2, RSPO1, CYP19A1, WNT4, ERα and ERβ, after one postnatal year in the ovotestis. Our results demonstrate that incomplete demethylation on the SRY gene is the driving cause of XY(DSD) in these XY DSD dogs, indicating a central role of epigenetic regulation in sex determination. PMID:27501986

  12. Generation of porcine fetal fibroblasts expressing the tetracycline-inducible Cas9 gene by somatic cell nuclear transfer

    PubMed Central

    Liu, Guoqian; Liu, Kai; Wei, Hengxi; Li, Li; Zhang, Shouquan

    2016-01-01

    Cas9 endonuclease, from so-called clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated (Cas) systems of Streptococcus pyogenes, type II functions as an RNA-guided endonuclease and edits the genomes of prokaryotic and eukaryotic organisms, including deletion and insertion by DNA double-stranded break repair mechanisms. In previous studies, it was observed that Cas9, with a genome-scale lentiviral single-guide RNA library, could be applied to a loss-of-function genetic screen, although the loss-of-function genes have yet to be verified in vitro and this approach has not been used in porcine cells. Based on these observations, lentiviral Cas9 was used to infect porcine primary fibroblasts to achieve cell colonies carrying Cas9 endonuclease. Subsequently, porcine fetal fibroblasts expressing the tetracycline-inducible Cas9 gene were generated by somatic cell nuclear transfer, and three 30 day transgenic porcine fetal fibroblasts (PFFs) were obtained. Polymerase chain reaction (PCR), reverse transcription-PCR and western blot analysis indicated that the PFFs were Cas9-positive. In addition, one of the three integrations was located near to known functional genes in the PFF1 cell line, whereas neither of the integrations was located in the PFF1 or PFF2 cell lines. It was hypothesized that these transgenic PFFs may be useful for conditional genomic editing in pigs, and for generating ideal modified porcine models. PMID:27430306

  13. Generation of GGTA1 biallelic knockout pigs via zinc-finger nucleases and somatic cell nuclear transfer.

    PubMed

    Bao, Lei; Chen, HaiDe; Jong, UiMyong; Rim, CholHo; Li, WenLing; Lin, XiJuan; Zhang, Dan; Luo, Qiong; Cui, Chun; Huang, HeFeng; Zhang, Yan; Xiao, Lei; Fu, ZhiXin

    2014-02-01

    Genetically modified pigs are valuable models of human disease and donors of xenotransplanted organs. Conventional gene targeting in pig somatic cells is extremely inefficient. Zinc-finger nuclease (ZFN) technology has been shown to be a powerful tool for efficiently inducing mutations in the genome. However, ZFN-mediated targeting in pigs has rarely been achieved. Here, we used ZFNs to knock out the porcine α-1, 3-galactosyl-transferase (GGTA1) gene, which generates Gal epitopes that trigger hyperacute immune rejection in pig-to-human transplantation. Primary pig fibroblasts were transfected with ZFNs targeting the coding region of GGTA1. Eighteen mono-allelic and four biallelic knockout cell clones were obtained after drug selection with efficiencies of 23.4% and 5.2%, respectively. The biallelic cells were used to produce cloned pigs via somatic cell nuclear transfer (SCNT). Three GGTA1 null piglets were born, and one knockout primary fibroblast cell line was established from a cloned fetus. Gal epitopes on GGTA1 null pig cells were completely eliminated from the cell membrane. Functionally, GGTA1 knockout cells were protected from complement-mediated immune attacks when incubated with human serum. This study demonstrated that ZFN is an efficient tool in creating gene-modified pigs. GGTA1 null pigs and GGTA1 null fetal fibroblasts would benefit research and pig-to-human transplantation. PMID:24430555

  14. 3D modeling of heat transfer and gas flow in a grooved ring fuel element for nuclear thermal propulsion

    NASA Astrophysics Data System (ADS)

    Barkett, Laura Ashley

    In the past, fuel elements with multiple axial coolant channels have been used in nuclear propulsion applications. A novel fuel element concept that reduces weight and increases efficiency uses a stack of grooved rings. Each fuel ring consists of a hole on the interior and grooves across the top face. Many grooved ring configurations have been modeled, and a single flow channel for each design has been analyzed. For increased efficiency, a fuel ring with a higher surface-area-to-volume ratio is ideal. When grooves are shallower and they have a lower surface area, the results show that the exit temperature is higher. By coupling the physics of fluid flow with those of heat transfer, the effects on the cooler gas flowing through the grooves of the hot, fissioning ring can be predicted. Models also show differences in velocities and temperatures after dense boundary nodes are applied. Parametric studies were done to show how a pressure drop across the length of the channels will affect the exit temperatures of the gas. Geometric optimization was done to show the temperature distributions and pressure drops that result from the manipulation of various parameters, and the effects of model scaling was also investigated. The inverse Graetz numbers are plotted against Nusselt numbers, and the results of these values suggest that the gas quickly becomes fully developed, laminar flow, rather than constant turbulent conditions.

  15. MicroRNA-145 Inhibitor Significantly Improves the Development of Bovine Somatic Cell Nuclear Transfer Embryos In Vitro.

    PubMed

    Li, Wenzhe; Xiong, Yongjie; Wang, Fengyu; Liu, Xin; Gao, Yang; Wang, Yongsheng; Zhang, Yong; Jin, Yaping

    2016-08-01

    Directly regulating the translation of POU5F1, SOX2, KLF4, and miRNA-145 plays an important role in maintaining the pluripotency of stem cells and the development of early embryos. In the present study, the expression model of miRNA-145 on bovine somatic cell nuclear transfer (SCNT) and in vitro fertilized (IVF) embryos were investigated and compared. Results indicated that (1) the expression level of miRNA-145 was significantly higher in SCNT embryos than that in IVF embryos after the eight-cell stage; (2) miRNA-145 negatively regulated the POU5F1, SOX2, and KLF4 in bovine embryos; (3) decreasing the expression of miRNA-145 by the miRNA-145 inhibitor significantly enhanced the expression of these three genes and the blastocyst formation rate; it also increased the total cell number and inner cell mass ratio of the bovine day 7 SCNT embryos. In conclusion, decreasing miRNA-145 expression might be a feasible means to enhance SCNT efficiency in bovines. PMID:27459582

  16. Trichostatin A specifically improves the aberrant expression of transcription factor genes in embryos produced by somatic cell nuclear transfer.

    PubMed

    Inoue, Kimiko; Oikawa, Mami; Kamimura, Satoshi; Ogonuki, Narumi; Nakamura, Toshinobu; Nakano, Toru; Abe, Kuniya; Ogura, Atsuo

    2015-01-01

    Although mammalian cloning by somatic cell nuclear transfer (SCNT) has been established in various species, the low developmental efficiency has hampered its practical applications. Treatment of SCNT-derived embryos with histone deacetylase (HDAC) inhibitors can improve their development, but the underlying mechanism is still unclear. To address this question, we analysed gene expression profiles of SCNT-derived 2-cell mouse embryos treated with trichostatin A (TSA), a potent HDAC inhibitor that is best used for mouse cloning. Unexpectedly, TSA had no effect on the numbers of aberrantly expressed genes or the overall gene expression pattern in the embryos. However, in-depth investigation by gene ontology and functional analyses revealed that TSA treatment specifically improved the expression of a small subset of genes encoding transcription factors and their regulatory factors, suggesting their positive involvement in de novo RNA synthesis. Indeed, introduction of one of such transcription factors, Spi-C, into the embryos at least partially mimicked the TSA-induced improvement in embryonic development by activating gene networks associated with transcriptional regulation. Thus, the effects of TSA treatment on embryonic gene expression did not seem to be stochastic, but more specific than expected, targeting genes that direct development and trigger zygotic genome activation at the 2-cell stage. PMID:25974394

  17. Potential of adipose-derived mesenchymal stem cells and skeletal muscle-derived satellite cells for somatic cell nuclear transfer mediated transgenesis in Arbas Cashmere goats.

    PubMed

    Ren, Yu; Wu, Haiqing; Ma, Yuzhen; Yuan, Jianlong; Liang, Hao; Liu, Dongjun

    2014-01-01

    Somatic cell nuclear transfer is used to generate genetic models for research and new, genetically modified livestock varieties. Goat fetal fibroblast cells (gFFCs) are the predominant nuclear donors in Cashmere goat transgenic cloning, but have disadvantages. We evaluated the potential of goat adipose-derived mesenchymal stem cells (gADSCs) and goat skeletal muscle-derived satellite cells (gMDSCs) for somatic cell nuclear transfer, evaluating their proliferation, pluripotency, transfection efficiency and capacity to support full term development of embryos after additive gene transfer or homologous recombination. gADSCs and gMDSCs were isolated by enzyme digestion and differentiated into neurocytes, myotube cells and insulin-producing cells. Neuron-specific enolase, fast muscle myosin and insulin expression were determined by immunohistochemistry. Following somatic cell nuclear transfer with donor cells derived from gADSCs, gMDSCs and gFFCs, transfection and cloning efficiencies were compared. Red fluorescent protein levels were determined by quantitative PCR and western blotting. 5-Methylcytosine, H4K5, H4K12 and H3K18 were determined immunohistochemically. gADSCs and gMDSCs were maintained in culture for up to 65 passages, whereas gFFCs could be passaged barely more than 15 times. gADSCs and gMDSCs had higher fluorescent colony forming efficiency and greater convergence (20%) and cleavage (10%) rates than gFFCs, and exhibited differing H4K5 histone modification patterns after somatic cell nuclear transfer and in vitro cultivation. After transfection with a pDsRed2-1 expression plasmid, the integrated exogenous genes did not influence the pluripotency of gADSCs-pDsRed2-1 or gMDSCs-pDsRed2-1. DsRed2 mRNA expression by cloned embryos derived from gADSCs-pDsRed2-1 or gMDSCs-pDsRed2-1 was more than twice that of gFFCs-pDsRed2-1 embryos (P<0.01). Pregnancy rates of gADSCs-pDsRed2-1 and gMDSCs-pDsRed2-1 recipients were higher than those of gFFCs-pDsRed2-1 recipients (P

  18. Potential of Adipose-Derived Mesenchymal Stem Cells and Skeletal Muscle-Derived Satellite Cells for Somatic Cell Nuclear Transfer Mediated Transgenesis in Arbas Cashmere Goats

    PubMed Central

    Yuan, Jianlong; Liang, Hao; Liu, Dongjun

    2014-01-01

    Somatic cell nuclear transfer is used to generate genetic models for research and new, genetically modified livestock varieties. Goat fetal fibroblast cells (gFFCs) are the predominant nuclear donors in Cashmere goat transgenic cloning, but have disadvantages. We evaluated the potential of goat adipose-derived mesenchymal stem cells (gADSCs) and goat skeletal muscle-derived satellite cells (gMDSCs) for somatic cell nuclear transfer, evaluating their proliferation, pluripotency, transfection efficiency and capacity to support full term development of embryos after additive gene transfer or homologous recombination. gADSCs and gMDSCs were isolated by enzyme digestion and differentiated into neurocytes, myotube cells and insulin-producing cells. Neuron-specific enolase, fast muscle myosin and insulin expression were determined by immunohistochemistry. Following somatic cell nuclear transfer with donor cells derived from gADSCs, gMDSCs and gFFCs, transfection and cloning efficiencies were compared. Red fluorescent protein levels were determined by quantitative PCR and western blotting. 5-Methylcytosine, H4K5, H4K12 and H3K18 were determined immunohistochemically. gADSCs and gMDSCs were maintained in culture for up to 65 passages, whereas gFFCs could be passaged barely more than 15 times. gADSCs and gMDSCs had higher fluorescent colony forming efficiency and greater convergence (20%) and cleavage (10%) rates than gFFCs, and exhibited differing H4K5 histone modification patterns after somatic cell nuclear transfer and in vitro cultivation. After transfection with a pDsRed2-1 expression plasmid, the integrated exogenous genes did not influence the pluripotency of gADSCs–pDsRed2-1 or gMDSCs–pDsRed2-1. DsRed2 mRNA expression by cloned embryos derived from gADSCs–pDsRed2-1 or gMDSCs–pDsRed2-1 was more than twice that of gFFCs–pDsRed2-1 embryos (P<0.01). Pregnancy rates of gADSCs–pDsRed2-1 and gMDSCs–pDsRed2-1 recipients were higher than those of gFFCs–pDsRed2

  19. Proteomic analysis of the major cellular proteins of bovine trophectoderm cell lines derived from IVP, parthenogenetic, and nuclear transfer embryos

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Nuclear cloning of cattle is currently very inefficient in terms of the production and survival of nuclear cloned calves. Because of the great promise of using nuclear cloning technology in farm animals to genetically improve their production and quality traits, nuclear cloning in cattle, and other...

  20. Development and investigations of compact heat-transfer equipment for a nuclear power station equipped with a high-temperature gas-cooled reactor

    NASA Astrophysics Data System (ADS)

    Golovko, V. F.; Dmitrieva, I. V.; Kodochigov, N. G.; Bykh, O. A.

    2013-07-01

    The project of a nuclear power station the reactor coolant system of which includes a high-temperature gas-cooled reactor combined with a gas-turbine energy conversion unit supposes the use of high-efficient gas-cycle-based heat-transfer equipment. An analysis aimed at selecting the optimal heat-transfer surfaces is presented together with the results from their calculated and experimental investigation. The design features of recuperators arranged integrally with end and intermediate coolers and placed in a vertical sealed high-pressure vessel of limited sizes are considered.

  1. Web-based Interspecies Correlation Estimation (Web-ICE) for Acute Toxicity: User Manual Version 3.1

    EPA Science Inventory

    Predictive toxicological models are integral to ecological risk assessment because data for most species are limited. Web-based Interspecies Correlation Estimation (Web-ICE) models are least square regressions that predict acute toxicity (LC50/LD50) of a chemical to a species, ge...

  2. SPECIES DIFFERENCES IN ANDROGEN AND ESTROGEN RECEPTOR STRUCTURE AND FUNCTION AMONG VERTEBRATES AND INVERTEBRATES: INTERSPECIES EXTRAPOLATIONS REGARDING ENDOCRINE DISRUPTING CHEMICALS

    EPA Science Inventory

    Species Differences in Androgen and Estrogen Receptor Structure and Function Among Vertebrates and Invertebrates: Interspecies Extrapolations regarding Endocrine Disrupting Chemicals
    VS Wilson1, GT Ankley2, M Gooding 1,3, PD Reynolds 1,4, NC Noriega 1, M Cardon 1, P Hartig1,...

  3. Interspecies transmission of equine influenza virus (H3N8) to dogs by close contact with experimentally infected horses.

    PubMed

    Yamanaka, Takashi; Nemoto, Manabu; Tsujimura, Koji; Kondo, Takashi; Matsumura, Tomio

    2009-11-18

    In horse populations, influenza A virus subtype H3N8 (equine influenza virus, EIV) is a very important pathogen that leads to acute respiratory disease. Recently, EIV has emerged in dogs, and has become widespread among the canine population in the United States. The interspecies transmission route had thus far remained unclear. Here, we tested whether the interspecies transmission of EIV to dogs could occur as a result of close contact with experimentally EIV-infected horses. Three pairs consisting of an EIV-infected horse and a healthy dog were kept together in individual stalls for 15 consecutive days. A subsequent hemagglutination inhibition test revealed that all three dogs exhibited seroconversion. Moreover, two of the three dogs exhibited virus shedding. However, the dogs exhibited no clinical signs throughout the course of the study. These data suggest that the interspecies transmission of EIV to dogs could occur as a result of close contact with EIV-infected horses without clinical symptoms. Although the interspecies transmission of EIV is unlikely to become an immediate threat to canine hygiene, close contact between EIV-infected horses and dogs should be avoided during an EI epidemic. PMID:19596528

  4. Human and Rat ABC Transporter Efflux of Bisphenol A and Bisphenol A Glucuronide: Interspecies Comparison and Implications for Pharmacokinetic Assessment

    EPA Science Inventory

    Significant interspecies differences exist between human and rodent with respect to absorption, distribution, and excretion of bisphenol A (BPA) and its primary metabolite, BPA-glucuronide (BPA-G). ATP-Binding Cassette (ABC) transporter enzymes play important roles in these physi...

  5. Aqueous and Tissue Residue-Based Interspecies Correlation Estimation Models Provide Conservative Hazard Estimates for Aromatic Compounds

    EPA Science Inventory

    Interspecies correlation estimation (ICE) models were developed for 30 nonpolar aromatic compounds to allow comparison of prediction accuracy between 2 data compilation approaches. Type 1 models used data combined across studies, and type 2 models used data combined only within s...

  6. Using Web-based Interspecies Correlation Estimation (Web-ICE) models as a tool for acute toxicity prediction

    EPA Science Inventory

    In order to assess risk of contaminants to taxa with limited or no toxicity data available, Interspecies Correlation Estimation (ICE) models have been developed by the U.S. Environmental Protection Agency to extrapolate contaminant sensitivity predictions based on data from commo...

  7. Vocal and visual stimulation, congruence and lateralization affect brain oscillations in interspecies emotional positive and negative interactions.

    PubMed

    Balconi, Michela; Vanutelli, Maria Elide

    2016-06-01

    The present research explored the effect of cross-modal integration of emotional cues (auditory and visual (AV)) compared with only visual (V) emotional cues in observing interspecies interactions. The brain activity was monitored when subjects processed AV and V situations, which represented an emotional (positive or negative), interspecies (human-animal) interaction. Congruence (emotionally congruous or incongruous visual and auditory patterns) was also modulated. electroencephalography brain oscillations (from delta to beta) were analyzed and the cortical source localization (by standardized Low Resolution Brain Electromagnetic Tomography) was applied to the data. Frequency band (mainly low-frequency delta and theta) showed a significant brain activity increasing in response to negative compared to positive interactions within the right hemisphere. Moreover, differences were found based on stimulation type, with an increased effect for AV compared with V. Finally, delta band supported a lateralized right dorsolateral prefrontal cortex (DLPFC) activity in response to negative and incongruous interspecies interactions, mainly for AV. The contribution of cross-modality, congruence (incongruous patterns), and lateralization (right DLPFC) in response to interspecies emotional interactions was discussed at light of a "negative lateralized effect." PMID:26256040

  8. INTERSPECIES CORRELATION ESTIMATION (ICE) FOR ACUTE TOXICITY TO AQUATIC ORGANISMS AND WILDLIFE. II. USER MANUAL AND SOFTWARE

    EPA Science Inventory

    Asfaw, Amha, Mark R. Ellersieck and Foster L. Mayer. 2003. Interspecies Correlation Estimations (ICE) for Acute Toxicity to Aquatic Organisms and Wildlife. II. User Manual and Software. EPA/600/R-03/106. U.S. Environmental Protection Agency, National Health and Environmental Effe...

  9. Interspecies allometric analysis of the comparative pharmacokinetics of 44 drugs across veterinary and laboratory animal species.

    PubMed

    Riviere, J E; Martin-Jimenez, T; Sundlof, S F; Craigmill, A L

    1997-12-01

    The purpose of this study was to apply the method of allometric analysis to a study of the comparative disposition of veterinary drugs using the Food Animal Residue Avoidance Databank (FARAD) as a source of the comparative pharmacokinetic data. An initial filtration of the FARAD data was performed in order to exclude drugs for which no pharmacokinetic data were available, in at least four species the route of administration was other than intravenous, and the matrix was different from blood, plasma or serum. This process restricted the study to a total of 44 candidate drugs. The primary pharmacokinetic parameter selected for study was half-life (t1/2). As this parameter is a composite of clearance (Cl) and volume of distribution (Vd), it was considered to be the most robust for interspecies scaling. Volume of distribution at steady state (Vdss) and clearance showed weak allometric correlations with weight across species. The relationships between body weight and elimination half-life (51/2 beta) were determined for this selected group of drugs by using the empirically determined function Y = a Wb. The function Y represents the parameter of concern (half-life), a is a coefficient typical of every drug (intercept), W is the species average body weight, and b is the scaling exponent. A total of 11 drugs (tetracycline, oxytetracycline, chlortetracycline, erythromycin, diazepam, prednisolone, cephapirin, ampicillin, gentamicin, apramycin and carbenicillin) showed statistically significant correlations and consequently are excellent candidates for interspecies extrapolation of pharmacokinetic parameters (half-life) in species of relevance to veterinary medicine. The remaining 33 drugs were divided into two groups which showed various degrees of lack of correlation. Many of the drugs that showed no allometric correlation were low hepatic extraction drugs. However, some other drugs demonstrated equivocal results which could either be due to a true lack of allometric

  10. Plant inter-species effects on rhizosphere priming effect and nitrogen acquisition by plants

    NASA Astrophysics Data System (ADS)

    Sun, Yue; Xu, Xingliang; Yang, Baijie; Kuzyakov, Yakov

    2015-04-01

    Rhizosphere interactions play a central role linking roots-soil system and regulate various aspects of nutrient cycling. Rhizodeposition inputs are known to change soil organic matter (SOM) decomposition via rhizosphere priming effects (RPEs) through enhancing soil biological activity and altering microbial community structure. The magnitude of RPEs varies widely among plant-species and root biomass possibly due to different quality and quantity of rhizodeposits. However, it is virtually unknown whether the RPEs are influenced by plant inter-species interactions and how these processes affect N mineralization and available N for plants. Monocultures of maize (M) and soybean (S), and mixed cultures of maize/maize (MM), soybean/soybean (SS), maize/soybean (MS) were grown over a 45-day greenhouse experiment. We labeled them with plant litter that was enriched in13C and 15N. The 15N distributions in plants and microbial biomass were measured at 14, 35, and 45days after labeling. The RPEs were positive under all plants, ranging from 11.7% to 138.3% and gradually decreased with plant growth. The RPE in the SS was significantly higher than these in others treatments at 14 days, while at 45 days it was higher in the MS than these from their monocultures, suggesting that the RPE was enhanced by the inter-species effects of maize and soybean. The litter decomposition ratio and 15N recovery of plants and microorganism increased with the root growth across all plants. The 15N recovery of plants in the MS (14.2%) was higher than these in the MM (12.3%) and SS(9.7%) at 45 days. Similarly, the 15N recovery of microorganism in the corresponding treatments was 6.7%, 2.2%, and 6.8%, respectively. The MS showed higher soil organic N mineralization amount than that from all soybean and maize monocultures at 45 days. We conclude that plant inter-species interactions may have significant effect on rhizosphere priming and modify the plant N uptake from litter resource and SOM.

  11. Plant inter-species effects on rhizosphere priming of soil organic matter decomposition

    NASA Astrophysics Data System (ADS)

    Pausch, Johanna; Zhu, Biao; Cheng, Weixin

    2015-04-01

    Living roots and their rhizodeposits can stimulate microbial activity and soil organic matter (SOM) decomposition up to several folds. This so-called rhizosphere priming effect (RPE) varies widely among plant species possibly due to species-specific differences in the quality and quantity of rhizodeposits and other root functions. However, whether the RPE is influenced by plant inter-species interactions remains largely unexplored, even though these interactions can fundamentally shape plant functions such as carbon allocation and nutrient uptake. In a 60-day greenhouse experiment, we continuously labeled monocultures and mixtures of sunflower, soybean and wheat with 13C-depleted CO2 and partitioned total CO2 efflux released from soil at two stages of plant development for SOM- and root-derived CO2. The RPE was calculated as the difference in SOM-derived CO2 between the planted and the unplanted soil, and was compared among the monocultures and mixtures. We found that the RPE was positive under all plants, ranging from 43% to 136% increase above the unplanted control. There were no significant differences in RPE at the vegetative stage. At the flowering stage however, the RPE in the soybean-wheat mixture was significantly higher than those in the sunflower monoculture, the sunflower-wheat mixture, and the sunflower-soybean mixture. These results indicated that the influence of plant inter-specific interactions on the RPE is case-specific and phenology-dependent. To evaluate the intensity of inter-specific effects on priming, we calculated an expected RPE for the mixtures based on the RPE of the monocultures weighted by their root biomass and compared it to the measured RPE under mixtures. At flowering, the measured RPE was significantly lower for the sunflower-wheat mixture than what can be expected from their monocultures, suggesting that RPE was significantly reduced by the inter-species effects of sunflower and wheat. In summary, our results clearly demonstrated

  12. Space transfer concepts and analysis for exploration missions. Implementation plan and element description document (draft final). Volume 5: Nuclear electric propulsion vehicle

    NASA Technical Reports Server (NTRS)

    1991-01-01

    The nuclear electric propulsion (NEP) concept design developed in support of the Space Transfer Concepts and Analysis for Exploration Missions (STCAEM) study is presented. The evolution of the NEP concept is described along with the requirements, guidelines, and assumptions for the design. Operating modes and options are defined and a systems description of the vehicle is presented. Artificial gravity configuration options and space and ground support systems are discussed. Finally, an implementation plan is presented which addresses technology needs, schedules, facilities and costs.

  13. Specific features of corrosion damage to heat-transfer tubes of steam generators used at nuclear power stations equipped with VVER-1000 reactors

    NASA Astrophysics Data System (ADS)

    Nemytov, D. S.; Tyapkov, V. F.

    2009-07-01

    Specific features of corrosion damage occurring to the heat-transfer tubes of steam generators used at nuclear power stations equipped with VVER-1000 reactors are considered. The results obtained from metallographic studies of flaws found in samples cut out from steam-generator tubes are analyzed. Regularities with which flaws of steam-generator tubes are distributed over the tube bundle volume are discussed. Approaches for assessing the technical state and remaining service life of steam-generator tubes are presented.

  14. Using a nano-flare probe to detect RNA in live donor cells prior to somatic cell nuclear transfer.

    PubMed

    Fu, Bo; Ren, Liang; Liu, Di; Ma, Jian-Zhang; An, Tie-Zhu; Yang, Xiu-Qin; Ma, Hong; Guo, Zhen-Hua; Zhu, Meng; Bai, Jing

    2016-01-01

    Many transgenes are silenced in mammalian cells (donor cells used for somatic cell nuclear transfer [SCNT]). Silencing correlated with a repressed chromatin structure or suppressed promoter, and it impeded the production of transgenic animals. Gene transcription studies in live cells are challenging because of the drawbacks of reverse-transcription polymerase chain reaction and fluorescence in situ hybridization. Nano-flare probes provide an effective approach to detect RNA in living cells. We used 18S RNA, a housekeeping gene, as a reference gene. This study aimed to establish a platform to detect RNA in single living donor cells using a Nano-flare probe prior to SCNT and to verify the safety and validity of the Nano-flare probe in order to provide a technical foundation for rescuing silenced transgenes in transgenic cloned embryos. We investigated cytotoxic effect of the 18S RNA-Nano-flare probe on porcine fetal fibroblasts, characterized the distribution of the 18S RNA-Nano-flare probe in living cells and investigated the effect of the 18S RNA-Nano-flare probe on the development of cloned embryos after SCNT. The cytotoxic effect of the 18S RNA-Nano-flare probe on porcine fetal fibroblasts was dose-dependent, and 18S RNA was detected using the 18S RNA-Nano-flare probe. In addition, treating donor cells with 500 pM 18S RNA-Nano-flare probe did not have adverse effects on the development of SCNT embryos at the pre-implantation stage. In conclusion, we established a preliminary platform to detect RNA in live donor cells using a Nano-flare probe prior to SCNT. PMID:26109144

  15. Ultrastructural comparison of porcine putative embryonic stem cells derived by in vitro fertilization and somatic cell nuclear transfer.

    PubMed

    Yoo, Hyunju; Kim, Eunhye; Hwang, Seon-Ung; Yoon, Junchul David; Jeon, Yubyeol; Park, Kyu-Mi; Kim, Kyu-Jun; Jin, Minghui; Lee, Chang-Kyu; Lee, Eunsong; Kim, Hyunggee; Kim, Gonhyung; Hyun, Sang-Hwan

    2016-04-22

    The ultrastructure of porcine putative embryonic stem cells and porcine fetal fibroblasts (PFFs) was analyzed by transmission electron microscopy. The aim of this study was to compare the features of organelles in in vitro fertilization (IVF) derived porcine embryonic stem cells (IVF-pESCs) and somatic cell nuclear transfer (SCNT) derived pESCs (SCNT-pESCs). Also, the features of organelles in high-passage IVF-pESCs were compared with those in low-passage cells. The ultrastructure of PFFs showed rare microvilli on the cell surfaces, polygonal or irregular nuclei with one to two reticular-shaped nucleoli and euchromatin, low cytoplasm-to-nucleus ratios, rare ribosomes, rare rough endoplasmic reticulum, elongated mitochondria, rich lysosomes and rich phagocytic vacuoles. IVF-pESCs showed rare microvilli on the cell surfaces, round or irregular nuclei with one to two reticular-shaped nucleoli and euchromatin, low cytoplasm-to-nucleus ratios, rich ribosomes, long stacks of rough endoplasmic reticulum, elongated mitochondria, rare lysosomes and rare autophagic vacuoles. By contrast, SCNT-pESCs showed rich microvilli with various lengths and frequencies on the cell surfaces, polygonal nuclei with one reticular shaped nucleoli and heterochromatin, high cytoplasm-to-nucleus ratios, rare ribosomes, rare rough endoplasmic reticulum, round mitochondria, rich lysosomes and rich phagocytic vacuoles with clear intercellular junctions. Furthermore, high-passage IVF-pESCs showed irregularly shaped colonies, pyknosis and numerous lysosomes associated with autophagic vacuoles showing signs of apoptosis. In conclusion, this study confirms that the ultrastructural characteristics of pESCs differ depending on their origin. These ultrastructural characteristics might be useful in biomedical research using pESCs, leading to new insights regarding regenerative medicine and tissue repair. PMID:26821870

  16. Plutonium from Above-Ground Nuclear Tests in Milk Teeth: Investigation of Placental Transfer in Children Born between 1951 and 1995 in Switzerland

    PubMed Central

    Froidevaux, Pascal; Haldimann, Max

    2008-01-01

    Background Occupational risks, the present nuclear threat, and the potential danger associated with nuclear power have raised concerns regarding the metabolism of plutonium in pregnant women. Objective We measured plutonium levels in the milk teeth of children born between 1951 and 1995 to assess the potential risk that plutonium incorporated by pregnant women might pose to the radiosensitive tissues of the fetus through placenta transfer. Methods We used milk teeth, whose enamel is formed during pregnancy, to investigate the transfer of plutonium from the mother’s blood plasma to the fetus. We measured plutonium using sensitive sector field inductively coupled plasma mass spectrometry techniques. We compared our results with those of a previous study on strontium-90 (90Sr) released into the atmosphere after nuclear bomb tests. Results Results show that plutonium activity peaks in the milk teeth of children born about 10 years before the highest recorded levels of plutonium fallout. By contrast, 90Sr, which is known to cross the placenta barrier, manifests differently in milk teeth, in accordance with 90Sr fallout deposition as a function of time. Conclusions These findings demonstrate that plutonium found in milk teeth is caused by fallout that was inhaled around the time the milk teeth were shed and not from any accumulation during pregnancy through placenta transfer. Thus, plutonium may not represent a radiologic risk for the radiosensitive tissues of the fetus. PMID:19079728

  17. Identification of transcriptome SNPs between Xiphophorus lines and species for assessing allele specific gene expression within F1 interspecies hybrids☆

    PubMed Central

    Shen, Yingjia; Catchen, Julian; Garcia, Tzintzuni; Amores, Angel; Beldroth, Ion; Wagner, Jonathon R; Zhang, Ziping; Postlethwait, John; Warren, Wes; Schartl, Manfred; Walter, Ronald B.

    2011-01-01

    Variations in gene expression are essential for the evolution of novel phenotypes and for speciation. Studying allelic specific gene expression (ASGE) within interspecies hybrids provides a unique opportunity to reveal underlying mechanisms of genetic variation. Using Xiphophorus interspecies hybrid fishes and high-throughput next generation sequencing technology, we were able to assess variations between two closely related vertebrate species, X. maculatus and X. couchianus, and their F1 interspecies hybrids. We constructed transcriptome-wide SNP polymorphism sets between two highly inbred X. maculatus lines (JP 163 A and B), and between X. maculatus and a second species, X. couchianus. The X. maculatus JP 163 A and B parental lines have been separated in the laboratory for ≈ 70 years and we were able to identify SNPs at a resolution of 1 SNP per 49 kb of transcriptome. In contrast, SNP polymorphisms between X. couchianus and X. maculatus species, which diverged ≈ 5–10 million years ago, were identified about every 700 bp. Using 6,524 transcripts with identified SNPs between the two parental species (X. maculatus and X. couchianus), we mapped RNA-seq reads to determine ASGE within F1 interspecies hybrids. We developed an in silico X. couchianus transcriptome by replacing 90,788 SNP bases for X. maculatus transcriptome with the consensus X. couchianus SNP bases and provide evidence that this procedure overcomes read mapping biases. Employment of the insilico reference transcriptome and tolerating 5 mismatches during read mapping allow direct assessment of ASGE in the F1 interspecies hybrids. Overall, these results show that Xiphophorus is a tractable vertebrate experimental model to investigate how genetic variations that occur during speciation may affect gene interactions and the regulation of gene expression. PMID:21466860

  18. Eating For Two: How Metabolism Establishes Interspecies Interactions in the Gut

    PubMed Central

    Fischbach, Michael A.; Sonnenburg, Justin L.

    2011-01-01

    In bacterial communities, ‘tight economic times’ are the norm. Of the many challenges bacteria face in making a living, perhaps none are more important than generating energy, maintaining redox balance, and acquiring carbon and nitrogen to synthesize primary metabolites. The ability of bacteria to meet these challenges depends heavily on the rest of their community. Indeed, the most fundamental way in which bacteria communicate is by importing the substrates for metabolism and exporting metabolic end products. As an illustration of this principle, we will travel down a carbohydrate catabolic pathway common to many species of Bacteroides, highlighting the interspecies interactions established (often inevitably) at its key steps. We also discuss the metabolic considerations in maintaining the stability of host-associated microbial communities. PMID:22018234

  19. Interspecies variation of Kitasatospora recifensis endophytic from yam bean producing thermostable amylases in alternative media.

    PubMed

    Stamford, Tania Lucia Montenegro; Stamford, Thayza Christina Montenegro; Stamford, Newton Pereira; Santos, Carolina Etienne Rosália Silva; de Lyra, Maria do Carmo Catanho Pereira; Ha-Park, Yong; Bae, Jin-Won; Araújo, Janete Magali

    2007-12-01

    An endophytic actinomycete isolated from tubers of yam beam (Pachyrhizus erosus L. Urban) was classified as a novel species nominated Kitasatospora recifensis based in phenotypic and genotypic analysis (16S rDNA gene sequence). Monosporic culture using specific ISP2 media revealed three interspecies, which were identified by DNA southern hybridization (Wild strain 13817 W, Aerial Mycelium strain 13817 AM and Vegetative Mycelium strain 13817 VM). The strains were tested for the production of amylolitic enzymes in alternative media. Maximum yields for both enzymes were observed in starch-casein. Higher α-amylase was obtained with strain 13817 W in starch-urea, and amyloglucosidase with strain 13817 AM in starch-ammonium that are economic sources and may be important for industrial purposes. Type strain (DAUFPE 13817(T) = KCTC 9972(T )= DSM 44943(T)). PMID:27517827

  20. Applications and limitations of interspecies scaling and in vitro extrapolation in pharmacokinetics.

    PubMed

    Lin, J H

    1998-12-01

    The search for new drugs is an extremely time-consuming and costly endeavor. Much of the time and cost are expended on generating data that support the efficacy and safety profiles of the drug. Because of ethical constraints, relevant pharmacological and toxicological assessments must be made in laboratory animals and in in vitro systems before human testing can begin. In support of the efficacy and safety evaluation during drug development, two fundamental challenges facing industrial drug metabolism scientists are (1) how to "scale-up" the pharmacokinetic data from animals to humans and (2) how to extrapolate the in vitro data to the in vivo situation. This review examines the applications and limitations of interspecies scaling and in vitro extrapolation in pharmacokinetics. PMID:9860929

  1. Development of algal interspecies correlation estimation models for chemical hazard assessment.

    PubMed

    Brill, Jessica L; Belanger, Scott E; Chaney, Joel G; Dyer, Scott D; Raimondo, Sandy; Barron, Mace G; Pittinger, Charles A

    2016-09-01

    Web-based Interspecies Correlation Estimation (ICE) is an application developed to predict the acute toxicity of a chemical from 1 species to another taxon. Web-ICE models use the acute toxicity value for a surrogate species to predict effect values for other species, thus potentially filling in data gaps for a variety of environmental assessment purposes. Web-ICE has historically been dominated by aquatic and terrestrial animal prediction models. Web-ICE models for algal species were essentially absent and are addressed in the present study. A compilation of public and private sector-held algal toxicity data were compiled and reviewed for quality based on relevant aspects of individual studies. Interspecies correlations were constructed from the most commonly tested algal genera for a broad spectrum of chemicals. The ICE regressions were developed based on acute 72-h and 96-h endpoint values involving 1647 unique studies on 476 unique chemicals encompassing 40 genera and 70 species of green, blue-green, and diatom algae. Acceptance criteria for algal ICE models were established prior to evaluation of individual models and included a minimum sample size of 3, a statistically significant regression slope, and a slope estimation parameter ≥0.65. A total of 186 ICE models were possible at the genus level, with 21 meeting quality criteria; and 264 ICE models were developed at the species level, with 32 meeting quality criteria. Algal ICE models will have broad utility in screening environmental hazard assessments, data gap filling in certain regulatory scenarios, and as supplemental information to derive species sensitivity distributions. Environ Toxicol Chem 2016;35:2368-2378. Published 2016 Wiley Periodicals Inc. on behalf of SETAC. This article is a US government work and, as such, is in the public domain in the United States of America. PMID:26792236

  2. [Advantages and limitations of interspecies associations in northern migratory sandpipers (Charadrii, Aves)].

    PubMed

    Gavrilov, V V

    2014-01-01

    Investigations were carried out at two stations of Ornithological Unit, IBPN FEB RAS, located in Nizhnekolymsk District, Yakutia, starting from May 15-20 in 1984, 1985, 1987, 1988, and 1990; at the northern coast of Pukhovoy Bay, Southern Island of Novaya Zemlya starting from June 1 in 1994; at Cape Beliy Nos, the Yugorsky Peninsula, starting from June 1 in 1995-1997. Classic associations are detected in interspecies flocks of sandpipers between the following species: the Pacific golden plover and the curlew sandpiper, the pectoral sandpiper and the long-billed dowitcher, the pectoral sandpiper and the dunlin, the grey plover and the dunlin. However, total amount of birds that form associations is not large. In species of group "A" (the grey plover, the Pacific golden plover, the pectoral sandpiper), no difference has been observed in migratory birds behavior within inter- or conspecific flocks. Species of group "B" (the dunlin, the curlew sandpiper, the long-billed dowitcher), on the contrary, change their behavior sharply depending on whether they belong to an association or not. Species of group "A" do not get any advantages when forming an association. Unlike them, species of group "B" profit from associating: a part of time spent in foraging substantially increases; more time is spent on rest and less time is spent on reconnaissance and vigilance (readiness for actions); safety of birds is enhanced. On the other hand, in species of group "B" there are also disadvantages related with associating: i.e., interspecies competition for food; foraging in suboptimal habitats which, in turn, may lead to notable increase of time spent by birds in foraging. An assumption is put forward that in species of group "B" advantages and limitations of associating cancel each other to a certain extent, and this explains rather small number of birds forming associations. PMID:25771678

  3. Discovering the Recondite Secondary Metabolome Spectrum of Salinispora Species: A Study of Inter-Species Diversity

    PubMed Central

    Bose, Utpal; Hewavitharana, Amitha K.; Vidgen, Miranda E.; Ng, Yi Kai; Shaw, P. Nicholas; Fuerst, John A.; Hodson, Mark P.

    2014-01-01

    Patterns of inter-species secondary metabolite production by bacteria can provide valuable information relating to species ecology and evolution. The complex nature of this chemical diversity has previously been probed via directed analyses of a small number of compounds, identified through targeted assays rather than more comprehensive biochemical profiling approaches such as metabolomics. Insights into ecological and evolutionary relationships within bacterial genera can be derived through comparative analysis of broader secondary metabolite patterns, and this can also eventually assist biodiscovery search strategies for new natural products. Here, we investigated the species-level chemical diversity of the two marine actinobacterial species Salinispora arenicola and Salinispora pacifica, isolated from sponges distributed across the Great Barrier Reef (GBR), via their secondary metabolite profiles using LC-MS-based metabolomics. The chemical profiles of these two species were obtained by UHPLC-QToF-MS based metabolic profiling. The resultant data were interrogated using multivariate data analysis methods to compare their (bio)chemical profiles. We found a high level of inter-species diversity in strains from these two bacterial species. We also found rifamycins and saliniketals were produced exclusively by S. arenicola species, as the main secondary metabolites differentiating the two species. Furthermore, the discovery of 57 candidate compounds greatly increases the small number of secondary metabolites previously known to be produced by these species. In addition, we report the production of rifamycin O and W, a key group of ansamycin compounds, in S. arenicola for the first time. Species of the marine actinobacteria harbour a much wider spectrum of secondary metabolites than suspected, and this knowledge may prove a rich field for biodiscovery as well as a database for understanding relationships between speciation, evolution and chemical ecology. PMID

  4. Interspecies Allometric Scaling of Antimalarial Drugs and Potential Application to Pediatric Dosing

    PubMed Central

    Senarathna, S. M. D. K. Ganga

    2014-01-01

    Pharmacopeial recommendations for administration of antimalarial drugs are the same weight-based (mg/kg of body weight) doses for children and adults. However, linear calculations are known to underestimate pediatric doses; therefore, interspecies allometric scaling data may have a role in predicting doses in children. We investigated the allometric scaling relationships of antimalarial drugs using data from pharmacokinetic studies in mammalian species. Simple allometry (Y = a × Wb) was utilized and compared to maximum life span potential (MLP) correction. All drugs showed a strong correlation with clearance (CL) in healthy controls. Insufficient data from malaria-infected species other than humans were available for allometric scaling. The allometric exponents (b) for CL of artesunate, dihydroartemisinin (from intravenous artesunate), artemether, artemisinin, clindamycin, piperaquine, mefloquine, and quinine were 0.71, 0.85, 0.66, 0.83, 0.62, 0.96, 0.52, and 0.40, respectively. Clearance was significantly lower in malaria infection than in healthy (adult) humans for quinine (0.07 versus 0.17 liter/h/kg; P = 0.0002) and dihydroartemisinin (0.81 versus 1.11 liters/h/kg; P = 0.04; power = 0.6). Interpolation of simple allometry provided better estimates of CL for children than MLP correction, which generally underestimated CL values. Pediatric dose calculations based on simple allometric exponents were 10 to 70% higher than pharmacopeial (mg/kg) recommendations. Interpolation of interspecies allometric scaling could provide better estimates than linear scaling of adult to pediatric doses of antimalarial drugs; however, the use of a fixed exponent for CL was not supported in the present study. The variability in allometric exponents for antimalarial drugs also has implications for scaling of fixed-dose combinations. PMID:25092696

  5. Chemical-specific adjustment factors (inter-species toxicokinetics) to establish the ADI for steviol glycosides.

    PubMed

    Roberts, Ashley; Lynch, Barry; Rogerson, Rebecca; Renwick, Andrew; Kern, Hua; Coffee, Matthew; Cuellar-Kingston, Nicole; Eapen, Alex; Crincoli, Christine; Pugh, George; Bhusari, Sachin; Purkayastha, Sidd; Carakostas, Michael

    2016-08-01

    The acceptable daily intake (ADI) of commercially available steviol glycosides is currently 0-4 mg/kg body weight (bw)/day, based on application of a 100-fold uncertainty factor to a no-observed-adverse-effect-level value from a chronic rat study. Within the 100-fold uncertainty factor is a 10-fold uncertainty factor to account for inter-species differences in toxicokinetics (4-fold) and toxicodynamics (2.5-fold). Single dose pharmacokinetics of stevioside were studied in rats (40 and 1000 mg/kg bw) and in male human subjects (40 mg/kg bw) to generate a chemical-specific, inter-species toxicokinetic adjustment factor. Tmax values for steviol were at ∼8 and ∼20 h after administration in rats and humans, respectively. Peak concentrations of steviol were similar in rats and humans, while steviol glucuronide concentrations were significantly higher in humans. Glucuronidation in rats was not saturated over the dose range 40-1000 mg/kg bw. The AUC0-last for steviol was approximately 2.8-fold greater in humans compared to rats. Chemical-specific adjustment factors for extrapolating toxicokinetics from rat to human of 1 and 2.8 were established based on Cmax and AUC0-last data respectively. Because these factors are lower than the default value of 4.0, a higher ADI for steviol glycosides of between 6 and 16 mg/kg bw/d is justified. PMID:27181453

  6. Molecular genetic response of Xiphophorus maculatus-X. couchianus interspecies hybrid skin to UVB exposure.

    PubMed

    Lu, Yuan; Bowswell, Mikki; Bowswell, William; Yang, Kuan; Schartl, Manfred; Walter, Ronald B

    2015-12-01

    The phenotypic and genetic similarities between Xiphophorus and human melanoma render Xiphophorus a useful animal model for studying the genetic basis of melanoma etiology. In the Xiphophorus model, melanoma has been shown to be inducible by ultraviolet light (UVB) exposure among interspecies hybrids, but not in parental line fish similarly treated. This leads to questions of what genes are responsive to UVB exposure in the skin of the interspecies hybrids, as well as how parental alleles in hybrids may be differentially regulated and the potential roles they may play in induced melanomagenesis. To address these questions, we produced X. maculatus Jp 163 B×X. couchianus (Sp-Couch) F1 hybrid fish, exposed both hybrid and parental fish to UVB, and performed gene expression profiling of the skin using RNA-Seq methodology. We characterized a group of unique UVB-responsive genes in Sp-Couch hybrid including dct, pmela, tyr, tyrp1a, slc2a11b, rab38a, rab27, tspan10, slc45a2, oca2, slc24a5, ptn and mitfa. These genes are associated with melanin production and melanocyte proliferation. They were also up-regulated in Sp-Couch hybrid, indicating that their UVB response is hybridization initiated. In the hybrid, several melanin production and pigmentation related genes, including slc45a2, tspan10, dct, slc2a11b and ptn showed either X. couchianus or X. maculatus allele specific expression. The finding that these genes exhibit allele specific expression regulatory mechanisms in Sp-Couch hybrids, but do not exhibit a corresponding UVB response in either one of the parental fishes, may suggest UVB targets and imply mechanisms regarding the susceptibility of Sp-Couch to induced melanomagenesis. PMID:26254713

  7. Thermal-Hydraulic Analyses of Heat Transfer Fluid Requirements and Characteristics for Coupling A Hydrogen Production Plant to a High-Temperature Nuclear Reactor

    SciTech Connect

    C. B. Davis; C. H. Oh; R. B. Barner; D. F. Wilson

    2005-06-01

    The Department of Energy is investigating the use of high-temperature nuclear reactors to produce hydrogen using either thermochemical cycles or high-temperature electrolysis. Although the hydrogen production processes are in an early stage of development, coupling either of these processes to the hightemperature reactor requires both efficient heat transfer and adequate separation of the facilities to assure that off-normal events in the production facility do not impact the nuclear power plant. An intermediate heat transport loop will be required to separate the operations and safety functions of the nuclear and hydrogen plants. A next generation high-temperature reactor could be envisioned as a single-purpose facility that produces hydrogen or a dual-purpose facility that produces hydrogen and electricity. Early plants, such as the proposed Next Generation Nuclear Plant, may be dual-purpose facilities that demonstrate both hydrogen and efficient electrical generation. Later plants could be single-purpose facilities. At this stage of development, both single- and dual-purpose facilities need to be understood. Seven possible configurations for a system that transfers heat between the nuclear reactor and the hydrogen and/or electrical generation plants were identified. These configurations included both direct and indirect cycles for the production of electricity. Both helium and liquid salts were considered as the working fluid in the intermediate heat transport loop. Methods were developed to perform thermalhydraulic and cycle-efficiency evaluations of the different configurations and coolants. The thermalhydraulic evaluations estimated the sizes of various components in the intermediate heat transport loop for the different configurations. The relative sizes of components provide a relative indication of the capital cost associated with the various configurations. Estimates of the overall cycle efficiency of the various configurations were also determined. The

  8. Technical aspects of the piezo, laser-assisted, and conventional methods for nuclear transfer of mouse oocytes and their efficiency and efficacy: Piezo minimizes damage of the ooplasmic membrane at injection.

    PubMed

    Chen, Shee-Uan; Chao, Kuang-Han; Chang, Chia-Yi; Hsieh, Fon-Jou; Ho, Hong-Nerng; Yang, Yu-Shih

    2004-04-01

    Assessment of the advantages and disadvantages of the piezo, laser, and conventional methods for nuclear transfer has remained elusive. Furthermore, although the piezo method had been used by some investigators for research of sperm injection and nuclear transfer for several years, many researchers have failed to operate the technique smoothly and achieve reproducible results. The procedures of nuclear transfer using piezo were ascertained and described in detail. Mouse oocytes were enucleated, and injected with cumulus cells using the piezo, laser, or conventional methods. We investigated the time needed and survival of nuclear transfer. Development was compared among the three methods and parthenogenetic control specimens. The average time of nuclear transfer for each oocyte was significantly shorter using the piezo (118 +/- 9 s) and laser methods (120 +/- 11 s) than using the conventional method (170 +/- 11 s). The damage rate was smaller for the piezo group (10%) than the laser (37%) and conventional (40%) groups. The percentages of blastocyst formation (14%, 12%, and 11%) and the number of nuclei of blastocysts (54 +/- 13, 51 +/- 11, and 52 +/- 12) were similar among the piezo, laser, and conventional groups, but significantly lower than for the control group (83%, 105 +/- 14). The piezo technique is more efficient than the conventional method for nuclear transfer. The laser method is easy to operate, but the equipment is expensive. In addition, piezo induced fewer traumas while breaking the membrane than the aspiration techniques used in the laser and conventional methods. PMID:15039993

  9. Application of the Web-based Interspecies Correlation Estimation (Web-ICE) tool to assess risks of national pesticide registrations to federally listed (threatened and endangered) species

    EPA Science Inventory

    The National Academy of Science (NAS) recently recommended exploration of predictive tools, such as interspecies correlation estimation (ICE), to estimate acute toxicity values for listed species and support development of species sensitivity distributions (SSDs). We explored the...

  10. INTERSPECIES DIFFERENCES IN THE STABILITY OF MAMMALIAN SPERM NUCLEI ASSESSED IN VIVO BY SPERM MICROINJECTION AND IN VITRO BY FLOW CYTOMETRY (JOURNAL VERSION)

    EPA Science Inventory

    To assess the structural stability of mammalian sperm nuclei and make interspecies comparison, sperm nuclei from six different species were injected into hamster oocytes. The time course of sperm decondensation varied considerably by species. Male pronuclei formed in oocytes inje...

  11. Canine distemper outbreak in raccoons suggests pathogen interspecies transmission amongst alien and native carnivores in urban areas from Germany.

    PubMed

    Rentería-Solís, Zaida; Förster, Christine; Aue, Angelika; Wittstatt, Ulrich; Wibbelt, Gudrun; König, Matthias

    2014-11-01

    From December 2012 to May 2013, an outbreak occurred among urban wild carnivores from Berlin. We collected 97 free-ranging raccoons from the city area. PCR assays, histopathology and immunohistochemistry confirmed canine distemper virus (CDV) infection in 74 raccoons. Phylogenetic analysis of haemagglutinin gene fragments (1767 nucleotides) of CDV isolated from four raccoons showed close relation to CDV isolates from foxes from Germany and a domestic dog from Hungary; all belonging to the "Europe" lineage of CDV. These study results suggest an inter-species transmission of CDV as the origin for the outbreak among the raccoon population. Implications for domestic pets and suggested interspecies transmission between urban wildlife and raccoons are discussed. This is the first major outbreak of CDV amongst free-ranging raccoons in Europe. PMID:25258173

  12. Effect of nuclear factor κB inhibition on serotype 9 adeno-associated viral (AAV9) minidystrophin gene transfer to the mdx mouse.

    PubMed

    Reay, Daniel P; Niizawa, Gabriela A; Watchko, Jon F; Daood, Molly; Reay, Ja'Nean C; Raggi, Eugene; Clemens, Paula R

    2012-01-01

    Gene therapy studies for Duchenne muscular dystrophy (DMD) have focused on viral vector-mediated gene transfer to provide therapeutic protein expression or treatment with drugs to limit dystrophic changes in muscle. The pathological activation of the nuclear factor (NF)-κB signaling pathway has emerged as an important cause of dystrophic muscle changes in muscular dystrophy. Furthermore, activation of NF-κB may inhibit gene transfer by promoting inflammation in response to the transgene or vector. Therefore, we hypothesized that inhibition of pathological NF-κB activation in muscle would complement the therapeutic benefits of dystrophin gene transfer in the mdx mouse model of DMD. Systemic gene transfer using serotype 9 adeno-associated viral (AAV9) vectors is promising for treatment of preclinical models of DMD because of vector tropism to cardiac and skeletal muscle. In quadriceps of C57BL/10ScSn-Dmd(mdx)/J (mdx) mice, the addition of octalysine (8K)-NF-κB essential modulator (NEMO)-binding domain (8K-NBD) peptide treatment to AAV9 minidystrophin gene delivery resulted in increased levels of recombinant dystrophin expression suggesting that 8K-NBD treatment promoted an environment in muscle tissue conducive to higher levels of expression. Indices of necrosis and regeneration were diminished with AAV9 gene delivery alone and to a greater degree with the addition of 8K-NBD treatment. In diaphragm muscle, high-level transgene expression was achieved with AAV9 minidystoophin gene delivery alone; therefore, improvements in histological and physiological indices were comparable in the two treatment groups. The data support benefit from 8K-NBD treatment to complement gene transfer therapy for DMD in muscle tissue that receives incomplete levels of transduction by gene transfer, which may be highly significant for clinical applications of muscle gene delivery. PMID:22231732

  13. Inter-Species Grafting Caused Extensive and Heritable Alterations of DNA Methylation in Solanaceae Plants

    PubMed Central

    Lin, Yan; Ma, Yiqiao; Liu, Gang; Yu, Xiaoming; Zhong, Silin; Liu, Bao

    2013-01-01

    Background Grafting has been extensively used to enhance the performance of horticultural crops. Since Charles Darwin coined the term “graft hybrid” meaning that asexual combination of different plant species may generate products that are genetically distinct, highly discrepant opinions exist supporting or against the concept. Recent studies have documented that grafting enables exchanges of both RNA and DNA molecules between the grafting partners, thus providing a molecular basis for grafting-induced genetic variation. DNA methylation is known as prone to alterations as a result of perturbation of internal and external conditions. Given characteristics of grafting, it is interesting to test whether the process may cause an alteration of this epigenetic marker in the grafted organismal products. Methodology/Principal Findings We analyzed relative global DNA methylation levels and locus-specific methylation patterns by the MSAP marker and locus-specific bisulfite-sequencing in the seed plants (wild-type controls), self- and hetero-grafted scions/rootstocks, selfed progenies of scions and their seed-plant controls, involving three Solanaceae species. We quantified expression of putative genes involved in establishing and/or maintaining DNA methylation by q-(RT)-PCR. We found that (1) hetero-grafting caused extensive alteration of DNA methylation patterns in a locus-specific manner, especially in scions, although relative methylation levels remain largely unaltered; (2) the altered methylation patterns in the hetero-grafting-derived scions could be inherited to sexual progenies with some sites showing further alterations or revisions; (3) hetero-grafting caused dynamic changes in steady-state transcript abundance of genes encoding for a set of enzymes functionally relevant to DNA methylation. Conclusions/Significance Our results demonstrate that inter-species grafting in plants could produce extensive and heritable alterations in DNA methylation. We suggest that

  14. ATP synthesis and degradation rates in the perfused rat heart. 31P-nuclear magnetic resonance double saturation transfer measurements.

    PubMed Central

    Spencer, R G; Balschi, J A; Leigh, J S; Ingwall, J S

    1988-01-01

    A limitation of magnetization transfer techniques for studying enzyme kinetics in vivo has been the difficulty of treating systems with more than two exchanging species. This problem was addressed in the original papers describing saturation transfer. Since then, a number of approaches have been devised to study these complex situations. Here, we present a method based on the transient saturation transfer experiment in which spin-lattice relaxation time constants and reaction rates are obtained from the same magnetization transfer data. This technique is particularly suitable for biological samples. We apply the method to evaluate flux balance in the three-site linear exchange network composed of ATP, creatine phosphate, and inorganic phosphate in the isolated, perfused rat heart and show that the method yields reasonable values for the reaction velocities of ATP synthesis and degradation. PMID:3242635

  15. Space transfer concepts and analysis for exploration missions. Implementation plan and element description document (draft final). Volume 3: Nuclear thermal rocket vehicle

    NASA Technical Reports Server (NTRS)

    1991-01-01

    This document presents the nuclear thermal rocket (NTR) concept design developed in support of the Space Transfer Concepts and Analysis for Exploration Missions (STCAEM) study. The evolution of the NTR concept is described along with the requirements, guidelines and assumptions for the design. Operating modes and options are defined and a systems description of the vehicle is presented. Artificial gravity configuration options and space and ground support systems are discussed. Finally, an implementation plan is presented which addresses technology needs, schedules, facilities and costs.

  16. Use of comparative genomics approaches to characterize interspecies differences in response to environmental chemicals: Challenges, opportunities, and research needs

    SciTech Connect

    Burgess-Herbert, Sarah L.; Euling, Susan Y.

    2013-09-15

    A critical challenge for environmental chemical risk assessment is the characterization and reduction of uncertainties introduced when extrapolating inferences from one species to another. The purpose of this article is to explore the challenges, opportunities, and research needs surrounding the issue of how genomics data and computational and systems level approaches can be applied to inform differences in response to environmental chemical exposure across species. We propose that the data, tools, and evolutionary framework of comparative genomics be adapted to inform interspecies differences in chemical mechanisms of action. We compare and contrast existing approaches, from disciplines as varied as evolutionary biology, systems biology, mathematics, and computer science, that can be used, modified, and combined in new ways to discover and characterize interspecies differences in chemical mechanism of action which, in turn, can be explored for application to risk assessment. We consider how genetic, protein, pathway, and network information can be interrogated from an evolutionary biology perspective to effectively characterize variations in biological processes of toxicological relevance among organisms. We conclude that comparative genomics approaches show promise for characterizing interspecies differences in mechanisms of action, and further, for improving our understanding of the uncertainties inherent in extrapolating inferences across species in both ecological and human health risk assessment. To achieve long-term relevance and consistent use in environmental chemical risk assessment, improved bioinformatics tools, computational methods robust to data gaps, and quantitative approaches for conducting extrapolations across species are critically needed. Specific areas ripe for research to address these needs are recommended.

  17. Characterization and Differential Expression of CPD and 6-4 DNA Photolyases in Xiphophorus Species and Interspecies Hybrids★

    PubMed Central

    Walter, Dylan J.; Boswell, Mikki; Volk de García, Sara M.; Walter, Sean M.; Breitenfeldt, Eric W.; Boswell, William; Walter, Ronald B.

    2014-01-01

    Among the many Xiphophorus interspecies hybrid tumor models are those that exhibit ultraviolet light (UVB) induced melanoma. In previous studies, assessment of UVB induced DNA damage and nucleotide excision DNA repair has been performed in parental lines and interspecies hybrids. Species and hybrid specific differences in the levels of DNA damage induced and the dark repair rates for cyclobutane pyrimidine dimers (CPDs) and 6-4 pyrimidine pyrimidine photoproducts (6-4PPs) have been reported. However, UVB induced DNA lesions in Xiphophorus fishes are thought to primarily be repaired via light dependent CPD and 6-4PP specific photolyases. Photolyases are of evolutionary interest since they are ancient and presumably function solely to ameliorate the deleterious effects of UVB exposure. Herein, we report results from detailed studies of CPD and 6-4PP photolyase gene expression within several Xiphophorus tissues. We determined photolyase gene expression patterns before and after exposure to fluorescent light in X. maculatus, X. couchianus, and for F1 interspecies hybrids produced from crossing these two parental lines (×. maculatus Jp 163 B × X. couchianus). We present novel results showing these two photolyase genes exhibit species, tissue, and hybrid-specific differences in basal and light induced gene expression. PMID:24496042

  18. Diffusible signal factor family signals provide a fitness advantage to Xanthomonas campestris pv. campestris in interspecies competition.

    PubMed

    Deng, Yinyue; Wu, Jien; Yin, Wenfang; Li, Peng; Zhou, Jianuan; Chen, Shaohua; He, Fei; Cai, Jun; Zhang, Lian-Hui

    2016-05-01

    Diffusible signal factor (DSF) represents a new class of widely conserved quorum sensing signals, which regulates various biological functions through intra- or interspecies signaling. The previous studies identified that there is an antagonistic interaction between Xanthomonas and Bacillus species bacteria in natural ecosystem, but the detailed molecular mechanism of interspecies competition is not clear. This study showed that Xanthomonas campestris pv. campestris (Xcc) interfered with morphological transition and sporulation of Bacillus thuringiensis in mixed cultures, whereas abrogation of the DSF synthase RpfF reduced the interference. DSF inhibited B. thuringiensis cell division and sporulation through modulation of ftsZ, which encodes an important cell division protein in bacterial cells. In addition, RpfF is essential for production of six DSF-family signals in Xcc, which employ the same signaling pathways to regulate biological functions in Xcc and play similar effects on reduction of cell division, sporulation and antibiotic resistance of B. thuringiensis. Furthermore, abrogation of RpfF decreased the competitive capability of Xcc against B. thuringiensis on the surface of Chinese cabbage leaves. Our findings provide new insights into the role of DSF-family signals in interspecies competition and depict molecular mechanisms with which Xcc competes with B. thuringiensis. PMID:26913592

  19. Chemically Assisted Enucleation Results in Higher G6PD Expression in Early Bovine Female Embryos Obtained by Somatic Cell Nuclear Transfer

    PubMed Central

    Oliveira, Clara Slade; Tetzner, Tatiane Almeida Drummond; de Lima, Marina Ragagnin; de Melo, Danilas Salinet; Niciura, Simone Cristina Méo; Garcia, Joaquim Mansano

    2012-01-01

    Abstract Despite extensive efforts, low efficiency is still an issue in bovine somatic cell nuclear transfer (SCNT). The hypothesis of our study was that the use of cytoplasts produced by chemically assisted enucleation (EN) would improve nuclear reprogramming in nuclear transfer (NT)–derived embryos because it results in lower damage and higher cytoplasm content than conventional EN. For that purpose, we investigated the expression of two X-linked genes: X inactive-specific transcript (XIST) and glucose 6-phosphate dehydrogenase (G6PD). In the first experiment, gene expression was assessed in day-7 female blastocysts from embryonic cell NT (ECNT) groups [conventional, ECNT conv; chemically assisted, ECNT deme (demecolcine)]. Whereas in the ECNT conv group, only one embryo (25%; n=4) expressed XIST transcripts, most embryos showed XIST expression (75%; n=4) in the ECNT deme group. However, no significant differences in transcript abundance of XIST and G6PD were found when comparing the embryos from all groups. In a second experiment using somatic cells as nuclear donors, we evaluated gene expression profiles in female SCNT-derived embryos. No significant differences in relative abundance (RA) of XIST transcripts were observed among the groups. Nonetheless, higher (p<0.05) levels of G6PD were observed in SCNT deme and in vitro–derived groups in comparison to SCNT conv. To know whether higher G6PD expression in embryos derived from SCNT chemically assisted EN indicates higher metabolism in embryos considered of superior quality or if the presence of higher reactive oxygen species (ROS) levels generated by the increased oxygen consumption triggers G6PD activation, the expression of genes related to stress response should be investigated in embryos produced by that technique. PMID:22908977

  20. Characterizing interspecies uncertainty using data from studies of anti-neoplastic agents in animals and humans

    SciTech Connect

    Price, Paul S. Keenan, Russell E.; Swartout, Jeffrey C.

    2008-11-15

    For most chemicals, the Reference Dose (RfD) is based on data from animal testing. The uncertainty introduced by the use of animal models has been termed interspecies uncertainty. The magnitude of the differences between the toxicity of a chemical in humans and test animals and its uncertainty can be investigated by evaluating the inter-chemical variation in the ratios of the doses associated with similar toxicological endpoints in test animals and humans. This study performs such an evaluation on a data set of 64 anti-neoplastic drugs. The data set provides matched responses in humans and four species of test animals: mice, rats, monkeys, and dogs. While the data have a number of limitations, the data show that when the drugs are evaluated on a body weight basis: 1) toxicity generally increases with a species' body weight; however, humans are not always more sensitive than test animals; 2) the animal to human dose ratios were less than 10 for most, but not all, drugs; 3) the current practice of using data from multiple species when setting RfDs lowers the probability of having a large value for the ratio. These findings provide insight into inter-chemical variation in animal to human extrapolations and suggest the need for additional collection and analysis of matched toxicity data in humans and test animals.

  1. Intra- and inter-species interactions within biofilms of important foodborne bacterial pathogens.

    PubMed

    Giaouris, Efstathios; Heir, Even; Desvaux, Mickaël; Hébraud, Michel; Møretrø, Trond; Langsrud, Solveig; Doulgeraki, Agapi; Nychas, George-John; Kačániová, Miroslava; Czaczyk, Katarzyna; Ölmez, Hülya; Simões, Manuel

    2015-01-01

    A community-based sessile life style is the normal mode of growth and survival for many bacterial species. Under such conditions, cell-to-cell interactions are inevitable and ultimately lead to the establishment of dense, complex and highly structured biofilm populations encapsulated in a self-produced extracellular matrix and capable of coordinated and collective behavior. Remarkably, in food processing environments, a variety of different bacteria may attach to surfaces, survive, grow, and form biofilms. Salmonella enterica, Listeria monocytogenes, Escherichia coli, and Staphylococcus aureus are important bacterial pathogens commonly implicated in outbreaks of foodborne diseases, while all are known to be able to create biofilms on both abiotic and biotic surfaces. Particularly challenging is the attempt to understand the complexity of inter-bacterial interactions that can be encountered in such unwanted consortia, such as competitive and cooperative ones, together with their impact on the final outcome of these communities (e.g., maturation, physiology, antimicrobial resistance, virulence, dispersal). In this review, up-to-date data on both the intra- and inter-species interactions encountered in biofilms of these pathogens are presented. A better understanding of these interactions, both at molecular and biophysical levels, could lead to novel intervention strategies for controlling pathogenic biofilm formation in food processing environments and thus improve food safety. PMID:26347727

  2. A biological approach to the interspecies prediction of radiation-induced mortality risk

    SciTech Connect

    Carnes, B.A.; Grahn, D.; Olshansky, S.J.

    1997-08-01

    Evolutionary explanations for why sexually reproducing organisms grow old suggest that the forces of natural selection affect the ages when diseases occur that are subject to a genetic influence (referred to here as intrinsic diseases). When extended to the population level for a species, this logic leads to the general prediction that age-specific death rates from intrinsic causes should begin to rise as the force of selection wanes once the characteristic age of sexual maturity is attained. Results consistent with these predictions have been found for laboratory mice, beagles, and humans where, after adjusting for differences in life span, it was demonstrated that these species share a common age pattern of mortality for intrinsic causes of death. In quantitative models used to predict radiation-induced mortality, risks are often expressed as multiples of those observed in a control population. A control population, however, is an aging population. As such, mortality risks related to exposure must be interpreted relative to the age-specific risk of death associated with aging. Given the previous success in making interspecies predictions of age-related mortality, the purpose of this study was to determine whether radiation-induced mortality observed in one species could also be predicted quantitatively from a model used to describe the mortality consequences of exposure to radiation in a different species. Mortality data for B6CF{sub 1} mice and beagles exposed to {sup 60}Co {gamma}-rays for the duration of life were used for analysis.

  3. Octopus lipid and vitamin E composition: interspecies, interorigin, and nutritional variability.

    PubMed

    Torrinha, Alvaro; Cruz, Rebeca; Gomes, Filipa; Mendes, Eulália; Casal, Susana; Morais, Simone

    2014-08-20

    Octopus vulgaris, Octopus maya, and Eledone cirrhosa from distinct marine environments [Northeast Atlantic (NEA), Northwest Atlantic (NWA), Eastern Central Atlantic, Western Central Atlantic (WCA), Pacific Ocean, and Mediterranean Sea] were characterized regarding their lipid and vitamin E composition. These species are those commercially more relevant worldwide. Significant interspecies and interorigin differences were observed. Unsaturated fatty acids account for more than 65% of total fatty acids, mostly ω-3 PUFA due to docosahexaenoic (18.4-29.3%) and eicosapentanoic acid (11.4-23.9%) contributions. The highest ω-3 PUFA amounts and ω-3/ω-6 ratios were quantified in the heaviest specimens, O. vulgaris from NWA, with high market price, and simultaneously in the lowest graded samples, E. cirrhosa from NEA, of reduced dimensions. Although having the highest cholesterol contents, E. cirrhosa from NEA and O. maya from WCA have also higher protective fatty acid indexes. Chemometric discrimination allowed clustering the selected species and several origins based on lipid and vitamin E profiles. PMID:25087929

  4. On being a (modern) scientist: risks of public engagement in the UK interspecies embryo debate

    PubMed Central

    Porter, James; Williams, Clare; Wainwright, Steven; Cribb, Alan

    2012-01-01

    In 2006, a small group of UK academic scientists made headlines when they proposed the creation of interspecies embryos – mixing human and animal genetic material. A public campaign was fought to mobilize support for the research. Drawing on interviews with the key scientists involved, this paper argues that engaging the public through communicating their ideas via the media can result in tensions between the necessity of, and inherent dangers in, scientists campaigning on controversial issues. Some scientists believed that communicating science had damaged their professional standing in the eyes of their peers, who, in turn, policed the boundaries around what they believed constituted a “good” scientist. Tensions between promoting “science” versus promotion of the “scientist;” engaging the public versus publishing peer-reviewed articles and winning grants; and building expectations versus overhyping the science reveal the difficult choices scientists in the modern world have to make over the potential gains and risks of communicating science. We conclude that although scientists' participation in public debates is often encouraged, the rewards of such engagement remain. Moreover, this participation can detrimentally affect scientists' careers. PMID:23293548

  5. The oxidative environment: a mediator of interspecies communication that drives symbiosis evolution

    PubMed Central

    Moné, Yves; Monnin, David; Kremer, Natacha

    2014-01-01

    Symbiotic interactions are ubiquitous in nature and play a major role in driving the evolution of life. Interactions between partners are often mediated by shared signalling pathways, which strongly influence both partners' biology and the evolution of the association in various environments. As an example of ‘common language’, the regulation of the oxidative environment plays an important role in driving the evolution of symbiotic associations. Such processes have been occurring for billions of years, including the increase in Earth's atmospheric oxygen and the subsequent evolution of mitochondria. The effect of reactive oxygen species and reactive nitrogen species (RONS) has been characterized functionally, but the molecular dialogue between partners has not been integrated within a broader evolutionary context yet. Given the pleiotropic role of RONS in cell–cell communication, development and immunity, but also their associated physiological costs, we discuss here how their regulation can influence the establishment, the maintenance and the breakdown of various symbiotic associations. By synthesizing recent developments in redox biology, we aim to provide an interdisciplinary understanding of the influence of such mediators of interspecies communication on the evolution and stability of symbioses, which in turn can shape ecosystems and play a role in health and disease. PMID:24807248

  6. The multifaceted roles of the interspecies signalling molecule indole in Agrobacterium tumefaciens.

    PubMed

    Lee, Jin-Hyung; Kim, Yong-Guy; Baek, Kwang-Hyun; Cho, Moo Hwan; Lee, Jintae

    2015-04-01

    Bacteria utilize signal molecules to ensure their survival in environmental niches, and indole is an interspecies and interkingdom signalling molecule, which is widespread in the natural environment. In this study, we sought to identify novel roles of indole in soil-borne bacterium Agrobacterium tumefaciens. Agrobacterium tumefaciens was found not to synthesize indole and to degrade it rapidly. The addition of exogenous indole dose-dependently inhibited A. tumefaciens growth and decreased its motility. Surprisingly, indole markedly increased A. tumefaciens biofilm formation on polystyrene, glass and nylon membrane surfaces and enhanced its antibiotic tolerance. Transcriptional analysis showed that indole markedly up-regulated several biofilm-related (celA, cheA, exoR, phoB, flgE, fliR and motA), stress-related genes (clpB, dnaK, gsp, gyrB, marR and soxR) and efflux genes (emrA, norM, and Atu2551) in A. tumefaciens, which partially explained the increased biofilm formation and antibiotic tolerance. In contrast, the plant auxin indole-3-acetic acid did not affect biofilm formation, antibiotic tolerance or gene expression. Interestingly, indole was found to exhibit several similarities with antibiotics, as it inhibited the growth of non-indole-producing bacteria, whereas these bacteria countered its effects by rapidly degrading indole, and by enhancing biofilm formation and antibiotic tolerance. PMID:25040348

  7. Non-Simian Foamy Viruses: Molecular Virology, Tropism and Prevalence and Zoonotic/Interspecies Transmission

    PubMed Central

    Kehl, Timo; Tan, Juan; Materniak, Magdalena

    2013-01-01

    Within the field of retrovirus, our knowledge of foamy viruses (FV) is still limited. Their unique replication strategy and mechanism of viral persistency needs further research to gain understanding of the virus-host interactions, especially in the light of the recent findings suggesting their ancient origin and long co-evolution with their nonhuman hosts. Unquestionably, the most studied member is the primate/prototype foamy virus (PFV) which was originally isolated from a human (designated as human foamy virus, HFV), but later identified as chimpanzee origin; phylogenetic analysis clearly places it among other Old World primates. Additionally, the study of non-simian animal FVs can contribute to a deeper understanding of FV-host interactions and development of other animal models. The review aims at highlighting areas of special interest regarding the structure, biology, virus-host interactions and interspecies transmission potential of primate as well as non-primate foamy viruses for gaining new insights into FV biology. PMID:24064793

  8. Old Meets New: Using Interspecies Interactions to Detect Secondary Metabolite Production in Actinomycetes

    PubMed Central

    Clardy, Jon; Kolter, Roberto

    2014-01-01

    Actinomycetes, a group of filamentous, Gram-positive bacteria, have long been a remarkable source of useful therapeutics. Recent genome sequencing and transcriptomic studies have shown that these bacteria, responsible for half of the clinically used antibiotics, also harbor a large reservoir of gene clusters, which have the potential to produce novel secreted small molecules. Yet, many of these clusters are not expressed under common culture conditions. One reason why these clusters have not been linked to a secreted small molecule lies in the way that actinomycetes have typically been studied: as pure cultures in nutrient-rich media that do not mimic the complex environments in which these bacteria evolved. New methods based on multispecies culture conditions provide an alternative approach to investigating the products of these gene clusters. We have recently implemented binary interspecies interaction assays to mine for new secondary metabolites and to study the underlying biology in inter-actinomycete interactions. Here we describe the detailed biological and chemical methods comprising these studies. PMID:23084935

  9. Interspecies comparison of marine reservoir ages at the Kitakogane shell midden, Hokkaido, Japan

    NASA Astrophysics Data System (ADS)

    Yoneda, Minoru; Shibata, Yasuyuki; Morita, Masatoshi; Hirota, Masashi; Suzuki, Ryo; Uzawa, Kazuhiro; Ohshima, Naoyuki; Dodo, Yukio

    2004-08-01

    Apparent 14C ages of human and faunal remains from the Kitakogane shell midden assigned to the Early Jomon period were measured to estimate the reservoir effect on different species. In previous studies, northern fur seal and Japanese deer had showed significant age differences of 860 14C yr, in concordance with the large reservoir ages observed in pre-bomb shells from the western North Pacific. However, the present study suggests that other sedentary marine organisms, including porpoise, Japanese sea lion and scallop, show a smaller reservoir age-offset at 720 14C yr at the same site. The ethology of northern fur seal was probably responsible for this discrepancy because of a larger reservoir age in the Sea of Okhotsk into which they migrated. This suggests the reservoir effect on humans was more complicated than a simple linear mixing between marine and terrestrial reservoirs in the case of the NW Pacific coast. It was suggested that an interspecies comparison of 14C age-offsets could produce more precise estimation of the marine reservoir effect in the past.

  10. Intra- and inter-species interactions within biofilms of important foodborne bacterial pathogens

    PubMed Central

    Giaouris, Efstathios; Heir, Even; Desvaux, Mickaël; Hébraud, Michel; Møretrø, Trond; Langsrud, Solveig; Doulgeraki, Agapi; Nychas, George-John; Kačániová, Miroslava; Czaczyk, Katarzyna; Ölmez, Hülya; Simões, Manuel

    2015-01-01

    A community-based sessile life style is the normal mode of growth and survival for many bacterial species. Under such conditions, cell-to-cell interactions are inevitable and ultimately lead to the establishment of dense, complex and highly structured biofilm populations encapsulated in a self-produced extracellular matrix and capable of coordinated and collective behavior. Remarkably, in food processing environments, a variety of different bacteria may attach to surfaces, survive, grow, and form biofilms. Salmonella enterica, Listeria monocytogenes, Escherichia coli, and Staphylococcus aureus are important bacterial pathogens commonly implicated in outbreaks of foodborne diseases, while all are known to be able to create biofilms on both abiotic and biotic surfaces. Particularly challenging is the attempt to understand the complexity of inter-bacterial interactions that can be encountered in such unwanted consortia, such as competitive and cooperative ones, together with their impact on the final outcome of these communities (e.g., maturation, physiology, antimicrobial resistance, virulence, dispersal). In this review, up-to-date data on both the intra- and inter-species interactions encountered in biofilms of these pathogens are presented. A better understanding of these interactions, both at molecular and biophysical levels, could lead to novel intervention strategies for controlling pathogenic biofilm formation in food processing environments and thus improve food safety. PMID:26347727

  11. Genotypic and phenotypic evolution of yeast interspecies hybrids during high-sugar fermentation.

    PubMed

    Lopandic, Ksenija; Pfliegler, Walter P; Tiefenbrunner, Wolfgang; Gangl, Helmut; Sipiczki, Matthias; Sterflinger, Katja

    2016-07-01

    The yeasts of the Saccharomyces genus exhibit a low pre-zygotic barrier and readily form interspecies hybrids. Following the hybridization event, the parental genomes undergo gross chromosomal rearrangements and genome modifications that may markedly influence the metabolic activity of descendants. In the present study, two artificially constructed hybrid yeasts (Saccharomyces cerevisiae x Saccharomyces uvarum and S. cerevisiae x Saccharomyces kudriavzevii) were used in order to evaluate the influence of high-sugar wine fermentation on the evolution of their genotypic and phenotypic properties. It was demonstrated that the extent of genomic modifications differs among the hybrids and their progeny, but that stress should not always be a generator of large genomic disturbances. The major genome changes were observed after meiosis in the F1 segregants in the form of the loss of different non-S. cerevisiae chromosomes. Under fermentation condition, each spore clone from a tetrad developed a mixed population characterized by different genotypic and phenotypic properties. The S. cerevisiae x S. uvarum spore clones revealed large modifications at the sequence level of the S. cerevisiae sub-genome, and some of the clones lost a few additional S. cerevisiae and S. uvarum chromosomes. The S. cerevisiae x S. kudriavzevii segregants were subjected to consecutive loss of the S. kudriavzevii markers and chromosomes. Both the hybrid types showed increased ethanol and glycerol production as well as better sugar consumption than their parental strains. The hybrid segregants responded differently to stress and a correlation was found between the observed genotypes and fermentation performances. PMID:27075738

  12. On being a (modern) scientist: risks of public engagement in the UK interspecies embryo debate.

    PubMed

    Porter, James; Williams, Clare; Wainwright, Steven; Cribb, Alan

    2012-12-01

    In 2006, a small group of UK academic scientists made headlines when they proposed the creation of interspecies embryos - mixing human and animal genetic material. A public campaign was fought to mobilize support for the research. Drawing on interviews with the key scientists involved, this paper argues that engaging the public through communicating their ideas via the media can result in tensions between the necessity of, and inherent dangers in, scientists campaigning on controversial issues. Some scientists believed that communicating science had damaged their professional standing in the eyes of their peers, who, in turn, policed the boundaries around what they believed constituted a "good" scientist. Tensions between promoting "science" versus promotion of the "scientist;" engaging the public versus publishing peer-reviewed articles and winning grants; and building expectations versus overhyping the science reveal the difficult choices scientists in the modern world have to make over the potential gains and risks of communicating science. We conclude that although scientists' participation in public debates is often encouraged, the rewards of such engagement remain. Moreover, this participation can detrimentally affect scientists' careers. PMID:23293548

  13. Interspecies allometric scaling: prediction of clearance in large animal species: part II: mathematical considerations.

    PubMed

    Martinez, M; Mahmood, I; Hunter, R P

    2006-10-01

    Interspecies scaling is a useful tool for the prediction of pharmacokinetic parameters from animals to humans, and it is often used for estimating a first-time in human dose. However, it is important to appreciate the mathematical underpinnings of this scaling procedure when using it to predict pharmacokinetic parameter values across animal species. When cautiously applied, allometry can be a tool for estimating clearance in veterinary species for the purpose of dosage selection. It is particularly valuable during the selection of dosages in large zoo animal species, such as elephants, large cats and camels, for which pharmacokinetic data are scant. In Part I, allometric predictions of clearance in large animal species were found to pose substantially greater risks of inaccuracies when compared with that observed for humans. In this report, we examine the factors influencing the accuracy of our clearance estimates from the perspective of the relationship between prediction error and such variables as the distribution of body weight values used in the regression analysis, the influence of a particular observation on the clearance estimate, and the 'goodness of fit' (R(2)) of the regression line. Ultimately, these considerations are used to generate recommendations regarding the data to be included in the allometric prediction of clearance in large animal species. PMID:16958788

  14. Activation of avian aryl hydrocarbon receptor and inter-species sensitivity variations by polychlorinated diphenylsulfides.

    PubMed

    Zhang, Rui; Zhang, Xiaowei; Zhang, Junjiang; Qu, Ruijuan; Zhang, Jiamin; Liu, Xing; Chen, Jun; Wang, Zunyao; Yu, Hongxia

    2014-09-16

    It was hypothesized that polychlorinated diphenyl sulfides (PCDPSs) can potentially interact with an aryl hydrocarbon receptor (AHR) and thereby cause adverse effects in wildlife like birds. A recently developed avian AHR1-luciferase report gene (LRG) assay was used to assess the interaction between avian AHR1 and 18 PCDPSs and to compare the interspecies sensitivity among chicken, ring-necked pheasant, and Japanese quail by PCDPSs. Most of the tested PCDPSs could activate the AHR1-mediated pathways in avian species, and the relative potency (ReP) of the PCDPSs increased with the increasing number of substituted Cl atoms. The rank orders of PCDPSs potency were generally similar among birds, although the ReP varied. In addition, not all the sensitivity rank orders of avian AHR1 constructs for PCDPSs were consistent with that of TCDD. ReP values of PCDPSs suggested that some PCDPSs like 2,3,3',4,5,6-hexa-CDPS and 2,2',3,3',4,5,6-hepta-CDPS are higher than the avian WHO-TEFs of OctaCDD, OctaCDF, and most of the coplanar PCBs. Our results report for the first time the activation of an AHR1-mediated molecular toxicological mechanism by PCDPSs, and provide the ranking of ReP and relative sensitivity values of different congeners, which could guide the further toxicity test of this group of potential high priority environmental pollutants. PMID:25141271

  15. The genetic basis of interspecies host preference differences in the model parasitoid Nasonia

    PubMed Central

    Desjardins, Christopher A; Perfectti, Francisco; Bartos, Jeremy D; Enders, Laramy S; Werren, John H

    2009-01-01

    The genetic basis of host preference has been investigated in only a few species. It is relevant to important questions in evolutionary biology, including sympatric speciation, generalist versus specialist adaptation, and parasite-host co-evolution. Here we show that a major locus strongly influences host preference in Nasonia. Nasonia are parasitic wasps that utilize fly pupae; N. vitripennis is a generalist that parasitizes a diverse set of hosts whereas N. giraulti specializes on Protocalliphora (bird blowflies). In laboratory choice experiments using Protocalliphora and Sarcophaga (flesh flies), N. vitripennis shows a preference for Sarcophaga while N. giraulti shows a preference for Protocalliphora. Through a series of interspecies crosses we have introgressed a major locus affecting host preference from N. giraulti into N. vitripennis. The N. giraulti allele is dominant and greatly increases preference for Protocalliphora pupae in the introgression line relative to the recessive N. vitripennis allele. Through the utilization of a Nasonia genotyping microarray, we have identified the introgressed region as 16 megabases of chromosome 4, although a more complete analysis is necessary to determine the exact genetic architecture of host preference in the genus. To our knowledge, this is the first introgression of the host preference of one parasitoid species into another, as well as one of the few cases of introgression of a behavioral gene between species. PMID:20087393

  16. Skin biopsy of Mediterranean cetaceans for the investigation of interspecies susceptibility to xenobiotic contaminants.

    PubMed

    Fossi, M C; Marsili, L; Neri, G; Casini, S; Bearzi, G; Politi, E; Zanardelli, M; Panigada, S

    2000-01-01

    Various studies on Mediterranean cetaceans have revealed bioaccumulation of contaminants such as organochlorines (OCs) and heavy metals. The susceptibility of these animals to organic pollutants and the relationship between bioaccumulation and population decline (as in the case of Delphinus delphis) are unexplored fields. In this study, we used a non-destructive approach (skin biopsy) to explore OC bioaccumulation processes and mixed-function oxidase activity (BPMO) in four species of cetaceans: striped dolphin (Stenella coeruleoalba), bottlenose dolphin (Tursiops truncatus), common dolphin (D. delphis) and fin whale (Balaenoptera physalus). Significant differences in BPMO induction and OC levels were found between odontocetes and mysticetes, the former having mixed-function oxidase activities four times higher than the latter, binding with levels of OCs one order of magnitude higher in odontocetes. A significant correlation (P < 0.05) between BPMO activities and OC levels was found in B. physalus. In an ongoing project, fibroblast cultures have been used as an alternative in vitro method of evaluating interspecies susceptibility to contaminants such as OCs and polycyclic aromatic hydrocarbons (PAHs). These results suggest that cetacean skin biopsies are a powerful non-invasive tool for assessing ecotoxicological risk to Mediterranean marine mammals species. PMID:11460743

  17. 'CATT' A project on Co-operation and Technology Transfer on Long-Term Radioactive Waste Management for EU Member States with Small Nuclear Programmes

    SciTech Connect

    Mathieson, J.; Lindberg, C.

    2006-07-01

    Many of the European Union's (EU) 25 countries have considerable inventories of long-lived radioactive waste that will remain potentially hazardous for many thousands of years. Of these, several have advanced concepts and programmes for the treatment and disposal (and other long - term management options) for spent fuel and long-lived radioactive waste. Collectively, these Member States have spent the equivalent of many billions of euros in developing such concepts and some have further developed the concepts into proposed operational facilities. Member States with small nuclear programmes, face the expensive and daunting prospect o f developing their own concepts for dealing with their spent fuel and high level waste. One answer would be to seek solutions which could take advantage of the investment costs in the technology and underpinning science already incurred in the more established programmes. Thus technology transfer between Member States in areas of high level waste and spent fuel encapsulation, repository development etc. would allow the establishment of disposal facilities within any Member State for it to deal with its own wastes. The national waste management organisations of the UK (Mirex), Sweden (SKB), German y (DBE), Lithuania (RATA), Bulgaria (DPRAO) and Slovenia (ARAO), together with JRC of the Netherlands, are to undertake a project under the auspices of the EU's 6. R and D Framework Programme (FP6). The 18 month project will examine the technical, intellectual property, legal, financial and societal implications of the idea. It goes by the acronym 'CATT' - 'Cooperation and technology transfer on long term radioactive waste management for Member States with small nuclear programmes'. This paper describes the CATT project which will look at technology transfer methodologies by which Member States could co-operate. It covers the potential issues which may arise and ho w these may be addressed. (authors)

  18. Topographical analysis of regulatory and metal ion binding sites on glutamine synthetase from Escherichia coli: 13C and 31P nuclear magnetic resonance and fluorescence energy transfer study

    PubMed Central

    Villafranca, J. J.; Rhee, S. G.; Chock, P. B.

    1978-01-01

    The paramagnetic effect of Mn(II) on 13C and 31P nuclear magnetic resonance signals from the [2-13C]ATP adenylylated glutamine synthetase [L-glutamate:ammonia ligase (ADP-forming); EC 6.3.1.2] from Escherichia coli was measured. This effect permitted the determination of distances from the 2-C position and the phosphorus of covalently bound AMP to the two Mn(II) binding sites, n1 and n2. Binding of Mn(II) to the n1 site converts an inactive apo-enzyme to its active form, while the metal ion bound at n2 occupies the metal-nucleotide substrate site. The distances from Mn(II) at the n1 and n2 sites to phosphorus are ∼10 and ∼7 Å and to the 2-C position of the adenine ring are ∼12 and ∼11 Å, respectively. The fluorescence energy transfer method was used to determine distances between Co(II) at n1 and n2 and the adenylyl site. For this experiment the enzyme was adenylylated with ε-ATP. The distances between ε-adenine and Co(II) at n1 and n2 are ∼13 and ∼11 Å, respectively. Quantitation of the paramagnetic effect due to Co(II) on the 31P nuclear magnetic resonance signal yielded values of 8 and 6 Å for the distances between the phosphorus of the covalently bound AMP and the n1 and n2 sites, respectively. The results reveal that the covalent modification site is very close to the catalytic center of the enzyme. In this study both nuclear magnetic resonance and fluorescence energy transfer techniques have been used to determine distances between the same set of sites on an enzyme surface. PMID:26053

  19. Bone Marrow Mesenchymal Stem Cells Are an Attractive Donor Cell Type for Production of Cloned Pigs As Well As Genetically Modified Cloned Pigs by Somatic Cell Nuclear Transfer

    PubMed Central

    Li, Zicong; He, Xiaoyan; Chen, Liwen; Shi, Junsong; Zhou, Rong; Xu, Weihua

    2013-01-01

    Abstract The somatic cell nuclear transfer (SCNT) technique has been widely applied to clone pigs or to produce genetically modified pigs. Currently, this technique relies mainly on using terminally differentiated fibroblasts as donor cells. To improve cloning efficiency, only partially differentiated multipotent mesenchymal stem cells (MSCs), thought to be more easily reprogrammed to a pluripotent state, have been used as nuclear donors in pig SCNT. Although in vitro–cultured embryos cloned from porcine MSCs (MSCs-embryos) were shown to have higher preimplantation developmental ability than cloned embryos reconstructed from fibroblasts (Fs-embryos), the difference in in vivo full-term developmental rate between porcine MSCs-embryos and Fs-embryos has not been investigated so far. In this study, we demonstrated that blastocyst total cell number and full-term survival abilities of MSCs-embryos were significantly higher than those of Fs-embryos cloned from the same donor pig. The enhanced developmental potential of MSCs-embryos may be associated with their nuclear donors' DNA methylation profile, because we found that the methylation level of imprinting genes and repeat sequences differed between MSCs and fibroblasts. In addition, we showed that use of transgenic porcine MSCs generated from transgene plasmid transfection as donor cells for SCNT can produce live transgenic cloned pigs. These results strongly suggest that porcine bone marrow MSCs are a desirable donor cell type for production of cloned pigs and genetically modified cloned pigs via SCNT. PMID:24033142

  20. Interspecies and intraspecies transmission of triple reassortant H3N2 influenza A viruses

    PubMed Central

    Yassine, Hadi M; Al-Natour, Mohammad Q; Lee, Chang-Won; Saif, Yehya M

    2007-01-01

    The triple reassortant H3N2 viruses were isolated for the first time from pigs in 1998 and are known to be endemic in swine and turkey populations in the United States. In 2004, we isolated two H3N2 triple reassortant viruses from two turkey breeder flocks in Ohio and Illinois. Infected hens showed no clinical signs, but experienced a complete cessation of egg production. In this study, we evaluated three triple reassortant H3N2 isolates of turkey origin and one isolate of swine origin for their transmission between swine and turkeys. Although all 4 viruses tested share high genetic similarity in all 8 genes, only the Ohio strain (A/turkey/Ohio/313053/04) was shown to transmit efficiently both ways between swine and turkeys. One isolate, A/turkey/North Carolina/03, was able to transmit from pigs to turkeys but not vice versa. Neither of the other two viruses transmitted either way. Sequence analysis of the HA1 gene of the Ohio strain showed one amino acid change (D to A) at residue 190 of the receptor binding domain upon transmission from turkeys to pigs. The Ohio virus was then tested for intraspecies transmission in three different avian species. The virus was shown to replicate and transmit among turkeys, replicate but does not transmit among chickens, and did not replicate in ducks. Identifying viruses with varying inter- and intra-species transmission potential should be useful for further studies on the molecular basis of interspecies transmission. PMID:18045494

  1. Spatial, temporal, and interspecies patterns in fine particulate matter in Texas.

    PubMed

    Gebhart, Kristi A; Malm, William C; Ashbaugh, Lowell L

    2005-11-01

    The Big Bend Regional Aerosol and Visibility Observational (BRAVO) field study was conducted from July to October 1999 and was followed by several years of modeling and data analyses to examine the causes of haze at Big Bend National Park TX (BBNP). During BRAVO, daily speciated fine (diameter <2.5 microm) particulate concentrations were measured at 37 sites throughout Texas. At the primary receptor site, K-Bar Ranch, there were many additional measurements including a "high-sensitivity" version of the 24-hr fine particulate elemental data. The spatial, temporal, and interspecies patterns in these data are examined here to qualitatively investigate source regions and source types influencing the fine particulate concentrations in Texas with an emphasis on sources of sulfates, the largest contributor to fine mass and light extinction. Peak values of particulate sulfur (S) varied spatially and seasonally. Maximum S was in Northeast Texas during the summer, whereas peak S at BBNP was in the fall. Sulfate acidity at BBNP also varied by month. Sources of Se were evident in Northeast Texas and from the Carbón I and II plants. High S episodes at BBNP during BRAVO had several different trace element characteristics. Carbon concentrations at BBNP during BRAVO were probably mostly urban-related, with arrival from the Houston area likely. The Houston artificial tracer released during the second half of BRAVO was highly correlated with some carbon fractions. There was evidence of the influence of African dust at sites throughout Texas during the summer. Patterns in several trace elements were also examined. Vanadium was associated with air masses from Mexico. Lead concentrations in southern Texas have dropped dramatically over the past several years. PMID:16350362

  2. Structural effects of PrP polymorphisms on intra- and interspecies prion transmission

    PubMed Central

    Angers, Rachel; Christiansen, Jeffrey; Nalls, Amy V.; Kang, Hae-Eun; Hunter, Nora; Hoover, Edward; Mathiason, Candace K.; Sheetz, Michael; Telling, Glenn C.

    2014-01-01

    Understanding the molecular parameters governing prion propagation is crucial for controlling these lethal, proteinaceous, and infectious neurodegenerative diseases. To explore the effects of prion protein (PrP) sequence and structural variations on intra- and interspecies transmission, we integrated studies in deer, a species naturally susceptible to chronic wasting disease (CWD), a burgeoning, contagious epidemic of uncertain origin and zoonotic potential, with structural and transgenic (Tg) mouse modeling and cell-free prion amplification. CWD properties were faithfully maintained in deer following passage through Tg mice expressing cognate PrP, and the influences of naturally occurring PrP polymorphisms on CWD susceptibility were accurately reproduced in Tg mice or cell-free systems. Although Tg mice also recapitulated susceptibility of deer to sheep prions, polymorphisms that provided protection against CWD had distinct and varied influences. Whereas substitutions at residues 95 and 96 in the unstructured region affected CWD propagation, their protective effects were overridden during replication of sheep prions in Tg mice and, in the case of residue 96, deer. The inhibitory effects on sheep prions of glutamate at residue 226 in elk PrP, compared with glutamine in deer PrP, and the protective effects of the phenylalanine for serine substitution at the adjacent residue 225, coincided with structural rearrangements in the globular domain affecting interaction between α-helix 3 and the loop between β2 and α-helix 2. These structure–function analyses are consistent with previous structural investigations and confirm a role for plasticity of this tertiary structural epitope in the control of PrP conversion and strain propagation. PMID:25034251

  3. Spatial, temporal, and interspecies patterns in fine particulate matter in Texas

    SciTech Connect

    Kristi A. Gebhart; William C. Malm; Lowell L. Ashbaugh

    2005-11-01

    The Big Bend Regional Aerosol and Visibility Observational (BRAVO) field study was conducted from July to October 1999 and was followed by several years of modeling and data analyses to examine the causes of haze at Big Bend National Park TX (BBNP). During BRAVO, daily speciated fine (diameter <2.5 {mu}m) particulate concentrations were measured at 37 sites throughout Texas. At the primary receptor site, K-Bar Ranch, there were many additional measurements including a 'high-sensitivity' version of the 24-hr fine particulate elemental data. The spatial, temporal, and interspecies patterns in these data are examined here to qualitatively investigate source regions and source types influencing the fine particulate concentrations in Texas with an emphasis on sources of sulfates, the largest contributor to fine mass and light extinction. Peak values of particulate sulfur (S) varied spatially and seasonally. Maximum S was in Northeast Texas during the summer, whereas peak S at BBNP was in the fall. Sulfate acidity at BBNP also varied by month. Sources of Se were evident in Northeast Texas and from the Carbon I and II coal-fired plants. High S episodes at BBNP during BRAVO had several different trace element characteristics. Carbon concentrations at BBNP during BRAVO were probably mostly urban-related, with arrival from the Houston area likely. The Houston artificial tracer released during the second half of BRAVO was highly correlated with some carbon fractions. There was evidence of the influence of African dust at sites throughout Texas during the summer. Patterns in several trace elements were also examined. Vanadium was associated with air masses from Mexico. Lead concentrations in southern Texas have dropped dramatically over the past several years. 23 refs., 9 figs., 2 tabs.

  4. Structural Plasticity of the Semliki Forest Virus Glycome upon Interspecies Transmission

    PubMed Central

    2014-01-01

    Cross-species viral transmission subjects parent and progeny alphaviruses to differential post-translational processing of viral envelope glycoproteins. Alphavirus biogenesis has been extensively studied, and the Semliki Forest virus E1 and E2 glycoproteins have been shown to exhibit differing degrees of processing of N-linked glycans. However the composition of these glycans, including that arising from different host cells, has not been determined. Here we determined the chemical composition of the glycans from the prototypic alphavirus, Semliki Forest virus, propagated in both arthropod and rodent cell lines, by using ion-mobility mass spectrometry and collision-induced dissociation analysis. We observe that both the membrane-proximal E1 fusion glycoprotein and the protruding E2 attachment glycoprotein display heterogeneous glycosylation that contains N-linked glycans exhibiting both limited and extensive processing. However, E1 contained predominantly highly processed glycans dependent on the host cell, with rodent and mosquito-derived E1 exhibiting complex-type and paucimannose-type glycosylation, respectively. In contrast, the protruding E2 attachment glycoprotein primarily contained conserved under-processed oligomannose-type structures when produced in both rodent and mosquito cell lines. It is likely that glycan processing of E2 is structurally restricted by steric-hindrance imposed by local viral protein structure. This contrasts E1, which presents glycans characteristic of the host cell and is accessible to enzymes. We integrated our findings with previous cryo-electron microscopy and crystallographic analyses to produce a detailed model of the glycosylated mature virion surface. Taken together, these data reveal the degree to which virally encoded protein structure and cellular processing enzymes shape the virion glycome during interspecies transmission of Semliki Forest virus. PMID:24467287

  5. Inter-species prediction of protein phosphorylation in the sbv IMPROVER species translation challenge

    PubMed Central

    Biehl, Michael; Sadowski, Peter; Bhanot, Gyan; Bilal, Erhan; Dayarian, Adel; Meyer, Pablo; Norel, Raquel; Rhrissorrakrai, Kahn; Zeller, Michael D.; Hormoz, Sahand

    2015-01-01

    Motivation: Animal models are widely used in biomedical research for reasons ranging from practical to ethical. An important issue is whether rodent models are predictive of human biology. This has been addressed recently in the framework of a series of challenges designed by the systems biology verification for Industrial Methodology for Process Verification in Research (sbv IMPROVER) initiative. In particular, one of the sub-challenges was devoted to the prediction of protein phosphorylation responses in human bronchial epithelial cells, exposed to a number of different chemical stimuli, given the responses in rat bronchial epithelial cells. Participating teams were asked to make inter-species predictions on the basis of available training examples, comprising transcriptomics and phosphoproteomics data. Results: Here, the two best performing teams present their data-driven approaches and computational methods. In addition, post hoc analyses of the datasets and challenge results were performed by the participants and challenge organizers. The challenge outcome indicates that successful prediction of protein phosphorylation status in human based on rat phosphorylation levels is feasible. However, within the limitations of the computational tools used, the inclusion of gene expression data does not improve the prediction quality. The post hoc analysis of time-specific measurements sheds light on the signaling pathways in both species. Availability and implementation: A detailed description of the dataset, challenge design and outcome is available at www.sbvimprover.com. The code used by team IGB is provided under http://github.com/uci-igb/improver2013. Implementations of the algorithms applied by team AMG are available at http://bhanot.biomaps.rutgers.edu/wiki/AMG-sc2-code.zip. Contact: meikelbiehl@gmail.com PMID:24994890

  6. Processing the Interspecies Quorum-sensing Signal Autoinducer-2 (AI-2)

    SciTech Connect

    J Marques; P Lamosa; C Russell; R Ventura; C Maycock; M Semmelhack; S Miller; K Xavier

    2011-12-31

    The molecule (S)-4,5-dihydroxy-2,3-pentanedione (DPD) is produced by many different species of bacteria and is the precursor of the signal molecule autoinducer-2 (AI-2). AI-2 mediates interspecies communication and facilitates regulation of bacterial behaviors such as biofilm formation and virulence. A variety of bacterial species have the ability to sequester and process the AI-2 present in their environment, thereby interfering with the cell-cell communication of other bacteria. This process involves the AI-2-regulated lsr operon, comprised of the Lsr transport system that facilitates uptake of the signal, a kinase that phosphorylates the signal to phospho-DPD (P-DPD), and enzymes (like LsrG) that are responsible for processing the phosphorylated signal. Because P-DPD is the intracellular inducer of the lsr operon, enzymes involved in P-DPD processing impact the levels of Lsr expression. Here we show that LsrG catalyzes isomerization of P-DPD into 3,4,4-trihydroxy-2-pentanone-5-phosphate. We present the crystal structure of LsrG, identify potential catalytic residues, and determine which of these residues affects P-DPD processing in vivo and in vitro. We also show that an lsrG deletion mutant accumulates at least 10 times more P-DPD than wild type cells. Consistent with this result, we find that the lsrG mutant has increased expression of the lsr operon and an altered profile of AI-2 accumulation and removal. Understanding of the biochemical mechanisms employed by bacteria to quench signaling of other species can be of great utility in the development of therapies to control bacterial behavior.

  7. Staphylococcus aureus Protein A Mediates Interspecies Interactions at the Cell Surface of Pseudomonas aeruginosa

    PubMed Central

    Armbruster, Catherine R.; Wolter, Daniel J.; Mishra, Meenu; Hayden, Hillary S.; Radey, Matthew C.; Merrihew, Gennifer; MacCoss, Michael J.; Burns, Jane; Wozniak, Daniel J.

    2016-01-01

    ABSTRACT While considerable research has focused on the properties of individual bacteria, relatively little is known about how microbial interspecies interactions alter bacterial behaviors and pathogenesis. Staphylococcus aureus frequently coinfects with other pathogens in a range of different infectious diseases. For example, coinfection by S. aureus with Pseudomonas aeruginosa occurs commonly in people with cystic fibrosis and is associated with higher lung disease morbidity and mortality. S. aureus secretes numerous exoproducts that are known to interact with host tissues, influencing inflammatory responses. The abundantly secreted S. aureus staphylococcal protein A (SpA) binds a range of human glycoproteins, immunoglobulins, and other molecules, with diverse effects on the host, including inhibition of phagocytosis of S. aureus cells. However, the potential effects of SpA and other S. aureus exoproducts on coinfecting bacteria have not been explored. Here, we show that S. aureus-secreted products, including SpA, significantly alter two behaviors associated with persistent infection. We found that SpA inhibited biofilm formation by specific P. aeruginosa clinical isolates, and it also inhibited phagocytosis by neutrophils of all isolates tested. Our results indicate that these effects were mediated by binding to at least two P. aeruginosa cell surface structures—type IV pili and the exopolysaccharide Psl—that confer attachment to surfaces and to other bacterial cells. Thus, we found that the role of a well-studied S. aureus exoproduct, SpA, extends well beyond interactions with the host immune system. Secreted SpA alters multiple persistence-associated behaviors of another common microbial community member, likely influencing cocolonization and coinfection with other microbes. PMID:27222468

  8. Interspecies communication in Streptococcus gordonii–Veillonella atypica biofilms: Signaling in flow conditions requires juxtaposition

    PubMed Central

    Egland, Paul G.; Palmer, Robert J.; Kolenbrander, Paul E.

    2004-01-01

    During the development of human oral biofilm communities, the spatial arrangement of the bacteria is thought to be driven by metabolic interactions between them. Streptococcus gordonii and Veillonella atypica, two early colonizing members of the dental plaque biofilm, have been postulated to participate in metabolic communication; S. gordonii ferments carbohydrates to form lactic acid, which is a preferred fermentation substrate for V. atypica. We found that, during agar-plate coculture of these organisms, a signaling event occurs that results in increased expression of the S. gordonii α-amylase-encoding gene amyB. Confocal scanning laser microscopy of coculture flowcell-grown biofilms using human saliva as the sole nutrient showed that V. atypica caused S. gordonii to increase expression of a PamyB-′gfp transcriptional fusion in a spatially resolved fashion. In this open system, only those streptococci in mixed-species microcolonies containing V. atypica expressed GFP; nearby S. gordonii colonies that lacked V. atypica did not express GFP. In a closed system containing S. gordonii and V. atypica, flow cytometric analysis showed that S. gordonii containing the PamyB-′gfp reporter plasmid exhibited mean fluorescence levels 20-fold higher than did S. gordonii that had not been incubated with V. atypica. Thus, in a closed system where a diffusible signal can accumulate above a required threshold, interspecies signaling mediates a change in gene expression. We provide evidence that, in open systems like those that predominate in natural biofilms, diffusible signals between species are designed to function over short distances, on the order of 1 μm. PMID:15546975

  9. Inter-species pathway perturbation prediction via data-driven detection of functional homology

    PubMed Central

    Hafemeister, Christoph; Romero, Roberto; Bilal, Erhan; Meyer, Pablo; Norel, Raquel; Rhrissorrakrai, Kahn; Bonneau, Richard; Tarca, Adi L.

    2015-01-01

    Motivation: Experiments in animal models are often conducted to infer how humans will respond to stimuli by assuming that the same biological pathways will be affected in both organisms. The limitations of this assumption were tested in the IMPROVER Species Translation Challenge, where 52 stimuli were applied to both human and rat cells and perturbed pathways were identified. In the Inter-species Pathway Perturbation Prediction sub-challenge, multiple teams proposed methods to use rat transcription data from 26 stimuli to predict human gene set and pathway activity under the same perturbations. Submissions were evaluated using three performance metrics on data from the remaining 26 stimuli. Results: We present two approaches, ranked second in this challenge, that do not rely on sequence-based orthology between rat and human genes to translate pathway perturbation state but instead identify transcriptional response orthologs across a set of training conditions. The translation from rat to human accomplished by these so-called direct methods is not dependent on the particular analysis method used to identify perturbed gene sets. In contrast, machine learning-based methods require performing a pathway analysis initially and then mapping the pathway activity between organisms. Unlike most machine learning approaches, direct methods can be used to predict the activation of a human pathway for a new (test) stimuli, even when that pathway was never activated by a training stimuli. Availability: Gene expression data are available from ArrayExpress (accession E-MTAB-2091), while software implementations are available from http://bioinformaticsprb.med.wayne.edu?p=50 and http://goo.gl/hJny3h. Contact: christoph.hafemeister@nyu.edu or atarca@med.wayne.edu. Supplementary information: Supplementary data are available at Bioinformatics online. PMID:25150249

  10. Interspecies allometric scaling. Part I: prediction of clearance in large animals.

    PubMed

    Mahmood, I; Martinez, M; Hunter, R P

    2006-10-01

    Interspecies scaling is a useful tool for the prediction of pharmacokinetic parameters from animals to humans, and it is often used for estimating a first-time in human dose. The knowledge of pharmacokinetics in veterinary species is important for dosage selection, particularly in the treatment of large zoo animal species, such as elephants, giant cats and camels, for which pharmacokinetic data are scant. Therefore, the accuracy in clearance predictions in large animal species, with and without the use of correction factors (rule of exponents), and the impact of species selection in the prediction of clearance in large animal species was examined. Based upon this analysis, it was determined that there is a much larger risk of inaccuracies in the clearance estimates in large animal species when compared with that observed for humans. Unlike in humans, for large animal species, correction factors could not be applied because there was no trend between the exponents of simple allometry and the appropriate correction factor for improving our predictions. Nevertheless, we did see an indication that the exponents of simple allometry may alert us as to when the predicted clearance in the large animal may be underestimated or overpredicted. For example, if a large animal is included in the scaling, the predicted clearance in a large animal should be considered overestimated if the exponent of simple allometry is >1.3. Despite the potential for extrapolation error, the reality is that allometric scaling is needed across many veterinary practice situations, and therefore will be used. For this reason, it is important to consider mechanisms for reducing the risk of extrapolation errors that can seriously affect target animal safety, therapeutic response, or the accuracy of withdrawal time predictions. PMID:16958787

  11. Dynamic epigenetic regulation of the Oct4 and Nanog regulatory regions during neural differentiation in rhesus nuclear transfer embryonic stem cells.

    PubMed

    Wang, Kai; Chen, Ying; Chang, Eun-Ah; Knott, Jason G; Cibelli, Jose B

    2009-12-01

    Oct4 and Nanog are crucial for maintaining pluripotency in embryonic stem (ES) cells and early-stage embryos. In the present study, the status of DNA methylation and of histone modifications in the regulatory regions of Oct4 and Nanog in rhesus nuclear transfer-derived ES (ntES) cells was compared with in vitro fertilized embryo-derived ES (IVFES) cell counterparts. Dynamic changes in DNA methylation during differentiation into neural lineage were also monitored and correlated with mRNA abundance and protein levels of both genes. In ntES cells Oct4 exhibited mono-allelic methylation along with relatively lower mRNA levels, and its transcription was seen predominantly from the unmethylated allele. In contrast, in IVFES cells Oct4 was hypomethylated on both alleles and had relatively higher transcript levels, suggesting incomplete reprogramming of DNA methylation on the Oct4 gene following somatic cell nuclear transfer. During neuronal differentiation, Oct4 underwent biallelic methylation and reduced amounts of Oct4 mRNA were detected in both types of ES cells. Analysis of Nanog regulatory regions revealed that both alleles were hypomethylated and similar levels of Nanog transcripts were expressed in ntES cells and IVFES cells. During neuronal differentiation both alleles were methylated and reduced amounts of Nanog mRNA were detected. Other epigenetic modifications including histone 3 lysine 4, 9, and 27 trimethylation (H3K4me3, H3K9me3, and H3K27me3) showed similar patterns around the regulatory regions of Oct4 and Nanog in both kinds of ES cells. During neural differentiation, dramatic enrichment of H3K27me3 and H3K9me3 (repressive marks) was observed on Oct4 and Nanog regulatory regions. Differentiation of ntES and IVFES cells correlated with the silencing of Oct4 and Nanog, reactivation of the neural marker genes Pax6, N-Oct3, and Olig2, and dynamic changes in histone modifications in the upstream regions of Pax6 and N-Oct3. In short, although ES cells derived

  12. Caffeine treatment prevents age-related changes in ovine oocytes and increases cell numbers in blastocysts produced by somatic cell nuclear transfer.

    PubMed

    Lee, Joon-Hee; Campbell, Keith H S

    2008-09-01

    Maturation-promoting factor (MPF) and mitogen-activated protein kinase (MAPK) are key regulators of both meiotic and mitotic cycles. Oocytes arrested at metaphase of the second meiotic division (MII) contain high levels of both kinases; however, these activities decline with age. Caffeine (an inhibitor of Myt1/Wee1 activity) can increase MPF and MAPK activities in ovine oocytes; however, the effects of caffeine treatment on the activation, nuclear configuration and developmental potential of ovine SC nuclear transfer (SCNT) embryos were unknown. We examined the effects of aging and caffeine treatment on MPF and MAPK activities, activation, development, and nuclear remodeling of SCNT embryos. Both kinases reached maximum activities at 24-h postonset of maturation (hpm) and then decreased with time. The decline in MPF activity occurred rapidly, whereas MAPK activity declined more slowly. Caffeine treatment (10.0 mM) of aging oocytes prevented the decline in activities associated with both kinases and prevented the acquisition of activation competence by a single activation stimulus. However, treatment of aged oocytes with caffeine could not increase kinase activities or reverse the acquisition of activation competence. Enucleation did not affect kinase activities, but caffeine treatment significantly increased both. Caffeine treatment did not affect the decline in MPF or MAPK activities following activation or significantly affect development of parthenogenetically activated oocytes. When SCNT reconstructed embryos were treated with caffeine following fusion, no increase in the frequency of development to blastocyst was observed; however, a significant increase in the occurrence of nuclear envelope break-down (NEBD) and an increase in total cell numbers occurred. PMID:18673075

  13. Investigation of using a Porous Media Approximation for Flow and Heat Transfer through the Nuclear Materials Storage Facility Drywell Array

    SciTech Connect

    Bernardin, J.D.; Gregory, W.S.; Owen, A.C.

    1999-04-21

    The Nuclear Materials Storage Facility (NMSF) is being renovated to provide a safe and secure long-term facility at Los Alamos National Laboratory to store nuclear materials. The concept for storage uses vertical tubes that are called drywells that have nuclear bearing canisters inside the tubes. The NMSF facility may use up to 370 of these tubes containing up to 10 canisters producing 15 W each. Analysts at the Laboratory wish to use CFD computer codes to predict the flow and thermal effects of air flow through the facility and the tube array. However, the complexity and large number of storage tubes precludes modeling the facility in enough detail to resolve the boundary layers around each and every tube. Therefore, certain approximations have to be made. A major approximation that has been used in this modeling effort has been to simulate the array of tubes as a porous media, The assumption-in the use of porous media is that the resistance of the drywells can be accounted for in a general way. The purpose of this study is to evaluate the suitability of the porous media approximation for modeling the tube array in the NMSF. In this study we will compare porous media models results with results from models that resolve the boundary layer around tubes. Finally, we offer a compromise modeling approach to address with this problem.

  14. A study of inter-species ion suppression in electrospray ionization-mass spectrometry of some phospholipid classes.

    PubMed

    Khoury, Spiro; El Banna, Nadine; Tfaili, Sana; Chaminade, Pierre

    2016-02-01

    Phospholipid quantification in biological samples is crucial and is increasingly studied in lipidomics. Quantitative studies are often performed using commercially available standards of phospholipid classes in order to mimic the composition of biological samples. For this, studies are conducted by liquid chromatography coupled to electrospray ionization-mass spectrometry. In liquid chromatography coupled to mass spectrometry (LC-MS) analysis, the matrix components and the co-elution of several phospholipid species lead to the phenomenon of ion suppression. As a result, a decrease in the response of phospholipid species in mass spectrometry MS is observed. In fact, inter-species ion suppression affects the efficiency of phospholipid (PL) ionization and might also influence the quantitative results. The aim of this work is to study the PL inter-species ion suppression phenomenon in electrospray ionization (ESI)-mass spectrometry on a triple quadrupole TQ and an LTQ-Orbitrap in order to improve quantification in natural and biological samples. Thus, the phospholipid MS response was evaluated to study the effect of acyl chain length, the degree, and the position of unsaturation on acyl chain and the effect of the polar head group structure. A number of saturated and unsaturated phospholipid species and mixtures were analyzed in different ionization modes to a better understanding of inter-species ion suppression phenomenon. PL molecular species responded differently according to the length of fatty acid chains, the number of unsaturation, and the nature of the polar head group. Fatty acid chain length showed to have the most marked effect on MS response. PMID:26780707

  15. Genomic interspecies microarray hybridization: rapid discovery of three thousand genes in the maize endophyte, Klebsiella pneumoniae 342, by microarray hybridization with Escherichia coli K-12 open reading frames.

    PubMed

    Dong, Y; Glasner, J D; Blattner, F R; Triplett, E W

    2001-04-01

    In an effort to efficiently discover genes in the diazotrophic endophyte of maize, Klebsiella pneumoniae 342, DNA from strain 342 was hybridized to a microarray containing 96% (n = 4,098) of the annotated open reading frames from Escherichia coli K-12. Using a criterion of 55% identity or greater, 3,000 (70%) of the E. coli K-12 open reading frames were also found to be present in strain 342. Approximately 24% (n = 1,030) of the E. coli K-12 open reading frames are absent in strain 342. For 1.6% (n = 68) of the open reading frames, the signal was too low to make a determination regarding the presence or absence of the gene. Genes with high identity between the two organisms are those involved in energy metabolism, amino acid metabolism, fatty acid metabolism, cofactor synthesis, cell division, DNA replication, transcription, translation, transport, and regulatory proteins. Functions that were less highly conserved included carbon compound metabolism, membrane proteins, structural proteins, putative transport proteins, cell processes such as adaptation and protection, and central intermediary metabolism. Open reading frames of E. coli K-12 with little or no identity in strain 342 included putative regulatory proteins, putative chaperones, surface structure proteins, mobility proteins, putative enzymes, hypothetical proteins, and proteins of unknown function, as well as genes presumed to have been acquired by lateral transfer from sources such as phage, plasmids, or transposons. The results were in agreement with the physiological properties of the two strains. Whole genome comparisons by genomic interspecies microarray hybridization are shown to rapidly identify thousands of genes in a previously uncharacterized bacterial genome provided that the genome of a close relative has been fully sequenced. This approach will become increasingly more useful as more full genome sequences become available. PMID:11282649

  16. Wolbachia infection shared among planthoppers (Homoptera: Delphacidae) and their endoparasite (Strepsiptera: Elenchidae): a probable case of interspecies transmission.

    PubMed

    Noda, H; Miyoshi, T; Zhang, Q; Watanabe, K; Deng, K; Hoshizaki, S

    2001-08-01

    Wolbachia, a group of parasitic bacteria of arthropods, are believed to be horizontally transmitted among arthropod taxa. We present a new probable example of interspecies horizontal transmission of Wolbachia by way of an endoparasite based on the conformity of Wolbachia gene sequences. Field samples of two rice planthoppers, Laodelphax striatellus and Sogatella furcifera possessed identical Wolbachia. Among three major endoparasites of planthoppers, a strepsipteran, Elenchus japonicus, harboured the identical Wolbachia strain, suggesting strepsipteran transmission of Wolbachia from one planthopper to the other. No Wolbachia was detected in a mermithid nematode Agamermis unka, and dryinid wasps possessed different types of Wolbachia. PMID:11555254

  17. Photographic evidence of interspecies mating in geckos of the Lepidodactylus lugubris unisexual-bisexual complex (Squamata: Gekkonidae)

    USGS Publications Warehouse

    Buden, Donald W.; Cianchini, Carlos; Taborosi, Danko; Fisher, Robert N.; Bauer, Aaron; Ineich, Ivan

    2014-01-01

    An interspecies mating between unisexual Lepidodactylus lugubris and a male of the bisexual Lepidodactylus moestus was photographed by Carlos Cianchini on Kosrae [Island], FSM, at 18:15 h on 22 August 2013 (Figure 1). The mating pair was on a window frame inside a house at Pukusruk Wan village (05°21'01" N, 163°00'41" E, elev. 28 m a.s.l.) on the northeastern side of the island. This is the first direct evidence of mating between these two species.

  18. Four-electron model for singlet and triplet excitation energy transfers with inclusion of coherence memory, inelastic tunneling and nuclear quantum effects

    NASA Astrophysics Data System (ADS)

    Suzuki, Yosuke; Ebina, Kuniyoshi; Tanaka, Shigenori

    2016-08-01

    A computational scheme to describe the coherent dynamics of excitation energy transfer (EET) in molecular systems is proposed on the basis of generalized master equations with memory kernels. This formalism takes into account those physical effects in electron-bath coupling system such as the spin symmetry of excitons, the inelastic electron tunneling and the quantum features of nuclear motions, thus providing a theoretical framework to perform an ab initio description of EET through molecular simulations for evaluating the spectral density and the temporal correlation function of electronic coupling. Some test calculations have then been carried out to investigate the dependence of exciton population dynamics on coherence memory, inelastic tunneling correlation time, magnitude of electronic coupling, quantum correction to temporal correlation function, reorganization energy and energy gap.

  19. Proliferating cell nuclear antigen (PCNA) interacts with a meiosis-specific RecA homologues, Lim15/Dmc1, but does not stimulate its strand transfer activity

    SciTech Connect

    Hamada, Fumika N.; Koshiyama, Akiyo; Namekawa, Satoshi H.; Ishii, Satomi; Iwabata, Kazuki; Sugawara, Hiroko; Nara, Takayuki Y.; Sakaguchi, Kengo . E-mail: kengo@rs.noda.tus.ac.jp; Sawado, Tomoyuki

    2007-01-26

    PCNA is a multi-functional protein that is involved in various nuclear events. Here we show that PCNA participates in events occurring during early meiotic prophase. Analysis of protein-protein interactions using surface plasmon resonance indicates that Coprinus cinereus PCNA (CoPCNA) specifically interacts with a meiotic specific RecA-like factor, C. cinereus Lim15/Dmc1 (CoLim15) in vitro. The binding efficiency increases with addition of Mg{sup 2+} ions, while ATP inhibits the interaction. Co-immunoprecipitation experiments indicate that the CoLim15 protein interacts with the CoPCNA protein in vitro and in the cell extracts. Despite the interaction between these two factors, no enhancement of CoLim15-dependent strand transfer activity by CoPCNA was found in vitro. We propose that the interaction between Lim15/Dmc1 and PCNA mediates the recombination-associated DNA synthesis during meiosis.

  20. A highly efficient method for generation of therapeutic quality human pluripotent stem cells by using naive induced pluripotent stem cells nucleus for nuclear transfer.

    PubMed

    Sanal, Madhusudana Girija

    2014-01-01

    Even after several years since the discovery of human embryonic stem cells and induced pluripotent stem cells (iPSC), we are still unable to make any significant therapeutic benefits out of them such as cell therapy or generation of organs for transplantation. Recent success in somatic cell nuclear transfer (SCNT) made it possible to generate diploid embryonic stem cells, which opens up the way to make high-quality pluripotent stem cells. However, the process is highly inefficient and hence expensive compared to the generation of iPSC. Even with the latest SCNT technology, we are not sure whether one can make therapeutic quality pluripotent stem cell from any patient's somatic cells or by using oocytes from any donor. Combining iPSC technology with SCNT, that is, by using the nucleus of the candidate somatic cell which got reprogrammed to pluripotent state instead that of the unmodified nucleus of the candidate somatic cell, would boost the efficiency of the technique, and we would be able to generate therapeutic quality pluripotent stem cells. Induced pluripotent stem cell nuclear transfer (iPSCNT) combines the efficiency of iPSC generation with the speed and natural reprogramming environment of SCNT. The new technique may be called iPSCNT. This technique could prove to have very revolutionary benefits for humankind. This could be useful in generating organs for transplantation for patients and for reproductive cloning, especially for childless men and women who cannot have children by any other techniques. When combined with advanced gene editing techniques (such as CRISPR-Cas system) this technique might also prove useful to those who want to have healthy children but suffer from inherited diseases. The current code of ethics may be against reproductive cloning. However, this will change with time as it happened with most of the revolutionary scientific breakthroughs. After all, it is the right of every human to have healthy offspring and it is the question of

  1. Measuring ligand-dependent and ligand-independent interactions between nuclear receptors and associated proteins using Bioluminescence Resonance Energy Transfer (BRET2)

    PubMed Central

    Koterba, Kristen L.; Rowan, Brian G.

    2006-01-01

    Bioluminescent resonance energy transfer (BRET2) is a recently developed technology for the measurement of protein-protein interactions in a live, cell-based system. BRET2 is characterized by the efficient transfer of excited energy between a bioluminescent donor molecule (Renilla luciferase) and a fluorescent acceptor molecule (a mutant of Green Fluorescent Protein (GFP2)). The BRET2 assay offers advantages over fluorescence resonance energy transfer (FRET) because it does not require an external light source thereby eliminating problems of photobleaching and autoflourescence. The absence of contamination by light results in low background that permits detection of very small changes in the BRET2 signal. BRET2 is dependent on the orientation and distance between two fusion proteins and therefore requires extensive preliminary standardization experiments to conclude a positive BRET2 signal independent of variations in protein titrations and arrangement in tertiary structures. Estrogen receptor (ER) signaling is modulated by steroid receptor coactivator 1 (SRC-1). To establish BRET2 in a ligand inducible system we used SRC-1 as the donor moiety and ER as the acceptor moiety. Expression and functionality of the fusion proteins were assessed by transient transfection in HEK-293 cells followed by Western blot analysis and measurement of ER-dependent reporter gene activity. These preliminary determinations are required prior to measuring nuclear receptor protein-protein interactions by BRET2. This article describes in detail the BRET2 methodology for measuring interaction between full-length ER and coregulator proteins in real-time, in an in vivo environment. PMID:17016546

  2. Interspecies Differences in Virus Uptake versus Cardiac Function of the Coxsackievirus and Adenovirus Receptor

    PubMed Central

    Freiberg, Fabian; Sauter, Martina; Pinkert, Sandra; Govindarajan, Thirupugal; Kaldrack, Joanna; Thakkar, Meghna; Fechner, Henry; Klingel, Karin

    2014-01-01

    ABSTRACT The coxsackievirus and adenovirus receptor (CAR) is a cell contact protein with an important role in virus uptake. Its extracellular immunoglobulin domains mediate the binding to coxsackievirus and adenovirus as well as homophilic and heterophilic interactions between cells. The cytoplasmic tail links CAR to the cytoskeleton and intracellular signaling cascades. In the heart, CAR is crucial for embryonic development, electrophysiology, and coxsackievirus B infection. Noncardiac functions are less well understood, in part due to the lack of suitable animal models. Here, we generated a transgenic mouse that rescued the otherwise embryonic-lethal CAR knockout (KO) phenotype by expressing chicken CAR exclusively in the heart. Using this rescue model, we addressed interspecies differences in coxsackievirus uptake and noncardiac functions of CAR. Survival of the noncardiac CAR KO (ncKO) mouse indicates an essential role for CAR in the developing heart but not in other tissues. In adult animals, cardiac activity was normal, suggesting that chicken CAR can replace the physiological functions of mouse CAR in the cardiomyocyte. However, chicken CAR did not mediate virus entry in vivo, so that hearts expressing chicken instead of mouse CAR were protected from infection and myocarditis. Comparison of sequence homology and modeling of the D1 domain indicate differences between mammalian and chicken CAR that relate to the sites important for virus binding but not those involved in homodimerization. Thus, CAR-directed anticoxsackievirus therapy with only minor adverse effects in noncardiac tissue could be further improved by selectively targeting the virus-host interaction while maintaining cardiac function. IMPORTANCE Coxsackievirus B3 (CVB3) is one of the most common human pathogens causing myocarditis. Its receptor, the coxsackievirus and adenovirus receptor (CAR), not only mediates virus uptake but also relates to cytoskeletal organization and intracellular signaling

  3. Inter-Species Comparative Analysis of Components of Soluble Sugar Concentration in Fleshy Fruits

    PubMed Central

    Dai, Zhanwu; Wu, Huan; Baldazzi, Valentina; van Leeuwen, Cornelis; Bertin, Nadia; Gautier, Hélène; Wu, Benhong; Duchêne, Eric; Gomès, Eric; Delrot, Serge; Lescourret, Françoise; Génard, Michel

    2016-01-01

    The soluble sugar concentration of fleshy fruit is a key determinant of fleshy fruit quality. It affects directly the sweetness of fresh fruits and indirectly the properties of processed products (e.g., alcohol content in wine). Despite considerable divergence among species, soluble sugar accumulation in a fruit results from the complex interplay of three main processes, namely sugar import, sugar metabolism, and water dilution. Therefore, inter-species comparison would help to identify common and/or species-specific modes of regulation in sugar accumulation. For this purpose, a process-based mathematical framework was used to compare soluble sugar accumulation in three fruits: grape, tomato, and peach. Representative datasets covering the time course of sugar accumulation during fruit development were collected. They encompassed 104 combinations of species (3), genotypes (30), and growing conditions (19 years and 16 nutrient and environmental treatments). At maturity, grape showed the highest soluble sugar concentrations (16.5–26.3 g/100 g FW), followed by peach (2.2 to 20 g/100 g FW) and tomato (1.4 to 5 g/100 g FW). Main processes determining soluble sugar concentration were decomposed into sugar importation, metabolism, and water dilution with the process-based analysis. Different regulation modes of soluble sugar concentration were then identified, showing either import-based, dilution-based, or import and dilution dual-based. Firstly, the higher soluble sugar concentration in grape than in tomato is a result of higher sugar importation. Secondly, the higher soluble sugar concentration in grape than in peach is due to a lower water dilution. The third mode of regulation is more complicated than the first two, with differences both in sugar importation and water dilution (grape vs. cherry tomato; cherry tomato vs. peach; peach vs. tomato). On the other hand, carbon utilization for synthesis of non-soluble sugar compounds (namely metabolism) was conserved

  4. Inter-Species Comparative Analysis of Components of Soluble Sugar Concentration in Fleshy Fruits.

    PubMed

    Dai, Zhanwu; Wu, Huan; Baldazzi, Valentina; van Leeuwen, Cornelis; Bertin, Nadia; Gautier, Hélène; Wu, Benhong; Duchêne, Eric; Gomès, Eric; Delrot, Serge; Lescourret, Françoise; Génard, Michel

    2016-01-01

    The soluble sugar concentration of fleshy fruit is a key determinant of fleshy fruit quality. It affects directly the sweetness of fresh fruits and indirectly the properties of processed products (e.g., alcohol content in wine). Despite considerable divergence among species, soluble sugar accumulation in a fruit results from the complex interplay of three main processes, namely sugar import, sugar metabolism, and water dilution. Therefore, inter-species comparison would help to identify common and/or species-specific modes of regulation in sugar accumulation. For this purpose, a process-based mathematical framework was used to compare soluble sugar accumulation in three fruits: grape, tomato, and peach. Representative datasets covering the time course of sugar accumulation during fruit development were collected. They encompassed 104 combinations of species (3), genotypes (30), and growing conditions (19 years and 16 nutrient and environmental treatments). At maturity, grape showed the highest soluble sugar concentrations (16.5-26.3 g/100 g FW), followed by peach (2.2 to 20 g/100 g FW) and tomato (1.4 to 5 g/100 g FW). Main processes determining soluble sugar concentration were decomposed into sugar importation, metabolism, and water dilution with the process-based analysis. Different regulation modes of soluble sugar concentration were then identified, showing either import-based, dilution-based, or import and dilution dual-based. Firstly, the higher soluble sugar concentration in grape than in tomato is a result of higher sugar importation. Secondly, the higher soluble sugar concentration in grape than in peach is due to a lower water dilution. The third mode of regulation is more complicated than the first two, with differences both in sugar importation and water dilution (grape vs. cherry tomato; cherry tomato vs. peach; peach vs. tomato). On the other hand, carbon utilization for synthesis of non-soluble sugar compounds (namely metabolism) was conserved among

  5. 8. Innovative Technologies: Two-Phase Heat Transfer in Water-Based Nanofluids for Nuclear Applications Final Report

    SciTech Connect

    Buongiorno, Jacopo; Hu, Lin-wen

    2009-07-31

    Nanofluids are colloidal dispersions of nanoparticles in water. Many studies have reported very significant enhancement (up to 200%) of the Critical Heat Flux (CHF) in pool boiling of nanofluids (You et al. 2003, Vassallo et al. 2004, Bang and Chang 2005, Kim et al. 2006, Kim et al. 2007). These observations have generated considerable interest in nanofluids as potential coolants for more compact and efficient thermal management systems. Potential Light Water Reactor applications include the primary coolant, safety systems and severe accident management strategies, as reported in other papers (Buongiorno et al. 2008 and 2009). However, the situation of interest in reactor applications is often flow boiling, for which no nanofluid data have been reported so far. In this project we investigated the potential of nanofluids to enhance CHF in flow boiling. Subcooled flow boiling heat transfer and CHF experiments were performed with low concentrations of alumina, zinc oxide, and diamond nanoparticles in water (≤ 0.1 % by volume) at atmospheric pressure. It was found that for comparable test conditions the values of the nanofluid and water heat transfer coefficient (HTC) are similar (within ±20%). The HTC increased with mass flux and heat flux for water and nanofluids alike, as expected in flow boiling. The CHF tests were conducted at 0.1 MPa and at three different mass fluxes (1500, 2000, 2500 kg/m2s) under subcooled conditions. The maximum CHF enhancement was 53%, 53% and 38% for alumina, zinc oxide and diamond, respectively, always obtained at the highest mass flux. A post-mortem analysis of the boiling surface reveals that its morphology is altered by deposition of the particles during nanofluids boiling. A confocal-microscopy-based examination of the test section revealed that nanoparticles deposition not only changes the number of micro-cavities on the surface, but also the surface wettability. A simple model was used to estimate the ensuing nucleation site

  6. Role of linker histone H1c during the reprogramming of Chinese swamp buffalo (Bubalus Bubalis) embryos produced by somatic cell nuclear transfer.

    PubMed

    Huang, Gao-Bo; Quan, Li; Zeng, Yong-Lian; Yang, Jian; Lu, Ke-Huan; Lu, Sheng-Sheng

    2016-03-01

    During reprogramming, there is exchange of histone H1c and the oocyte-specific linker histone, and H1c may play a critically important role in the reprogramming process of somatic cell nuclear transfer (SCNT). The aim of the present study was to investigate the role of the H1c gene in SCNT reprogramming in Chinese swamp buffalo (Bubalus bubalis) using RNA interference (RNAi). Chinese swamp buffalo H1c gene sequences were obtained and H1c-RNAi vectors were designed, synthesised and then transfected into a buffalo fetal skin fibroblast cell line. Expression of H1c was determined by real-time polymerase chain reaction to examine the efficiency of vector interference. These cells were then used as a nuclear donor for SCNT so as to observe the further development of SCNT embryos. Inhibition of H1c gene expression in donor cells significantly improved the developmental speed of embryos from the 1-cell to 8-cell stage. Furthermore, compared with the control group, inhibition of H1c gene expression significantly reduced the blastocyst formation rate. It is concluded that linker histone H1c is very important in SCNT reprogramming in Chinese swamp buffalo. Correct expression of the H1c gene plays a significant role in preimplantation embryonic development in B. bubalis. PMID:25145348

  7. Production of CFTR-null and CFTR-ΔF508 heterozygous pigs by adeno-associated virus–mediated gene targeting and somatic cell nuclear transfer

    PubMed Central

    Rogers, Christopher S.; Hao, Yanhong; Rokhlina, Tatiana; Samuel, Melissa; Stoltz, David A.; Li, Yuhong; Petroff, Elena; Vermeer, Daniel W.; Kabel, Amanda C.; Yan, Ziying; Spate, Lee; Wax, David; Murphy, Clifton N.; Rieke, August; Whitworth, Kristin; Linville, Michael L.; Korte, Scott W.; Engelhardt, John F.; Welsh, Michael J.; Prather, Randall S.

    2008-01-01

    Progress toward understanding the pathogenesis of cystic fibrosis (CF) and developing effective therapies has been hampered by lack of a relevant animal model. CF mice fail to develop the lung and pancreatic disease that cause most of the morbidity and mortality in patients with CF. Pigs may be better animals than mice in which to model human genetic diseases because their anatomy, biochemistry, physiology, size, and genetics are more similar to those of humans. However, to date, gene-targeted mammalian models of human genetic disease have not been reported for any species other than mice. Here we describe the first steps toward the generation of a pig model of CF. We used recombinant adeno-associated virus (rAAV) vectors to deliver genetic constructs targeting the CF transmembrane conductance receptor (CFTR) gene to pig fetal fibroblasts. We generated cells with the CFTR gene either disrupted or containing the most common CF-associated mutation (ΔF508). These cells were used as nuclear donors for somatic cell nuclear transfer to porcine oocytes. We thereby generated heterozygote male piglets with each mutation. These pigs should be of value in producing new models of CF. In addition, because gene-modified mice often fail to replicate human diseases, this approach could be used to generate models of other human genetic diseases in species other than mice. PMID:18324337

  8. Production of CFTR-null and CFTR-DeltaF508 heterozygous pigs by adeno-associated virus-mediated gene targeting and somatic cell nuclear transfer.

    PubMed

    Rogers, Christopher S; Hao, Yanhong; Rokhlina, Tatiana; Samuel, Melissa; Stoltz, David A; Li, Yuhong; Petroff, Elena; Vermeer, Daniel W; Kabel, Amanda C; Yan, Ziying; Spate, Lee; Wax, David; Murphy, Clifton N; Rieke, August; Whitworth, Kristin; Linville, Michael L; Korte, Scott W; Engelhardt, John F; Welsh, Michael J; Prather, Randall S

    2008-04-01

    Progress toward understanding the pathogenesis of cystic fibrosis (CF) and developing effective therapies has been hampered by lack of a relevant animal model. CF mice fail to develop the lung and pancreatic disease that cause most of the morbidity and mortality in patients with CF. Pigs may be better animals than mice in which to model human genetic diseases because their anatomy, biochemistry, physiology, size, and genetics are more similar to those of humans. However, to date, gene-targeted mammalian models of human genetic disease have not been reported for any species other than mice. Here we describe the first steps toward the generation of a pig model of CF. We used recombinant adeno-associated virus (rAAV) vectors to deliver genetic constructs targeting the CF transmembrane conductance receptor (CFTR) gene to pig fetal fibroblasts. We generated cells with the CFTR gene either disrupted or containing the most common CF-associated mutation (DeltaF508). These cells were used as nuclear donors for somatic cell nuclear transfer to porcine oocytes. We thereby generated heterozygote male piglets with each mutation. These pigs should be of value in producing new models of CF. In addition, because gene-modified mice often fail to replicate human diseases, this approach could be used to generate models of other human genetic diseases in species other than mice. PMID:18324337

  9. The TOCATTA-χ model for assessing 14C transfers to grass: an evaluation for atmospheric operational releases from nuclear facilities.

    PubMed

    Aulagnier, Céline; Le Dizès, Séverine; Maro, Denis; Hébert, Didier; Lardy, Romain; Martin, Raphael

    2013-06-01

    Radioactive (14)C is formed as a by-product of nuclear power generation and from the operation of nuclear fuel reprocessing plants like AREVA-NC La Hague (North France), which releases about 15 TBq per year of (14)C into the atmosphere. This article evaluates a recently improved radioecology model (TOCATTA-χ) to assess (14)C transfers to grassland ecosystems under normal operating conditions. The new version of the TOCATTA model (TOCATTA-χ) includes developments that were derived from PaSiM, a pasture model for simulating grassland carbon and radiocarbon cycling. The TOCATTA-χ model has been tested against observations of (14)C activity concentrations in grass samples collected monthly from six plots which are located around the periphery of the reprocessing plant. Simulated (14)C activities are consistent with observations on both intensively managed and poorly managed grasslands, but an adaptation of the mean turn-over time for (14)C within the plant is necessary in the model to account for different management practices. When atmospheric (14)C activity concentrations are directly inferred from observations, TOCATTA-χ performs better than TOCATTA (the root mean square error is decreased by 45%), but when atmospheric (14)C activity concentrations are not known and must be calculated, the uncertainty associated with the TOCATTA-χ model outcomes is estimated to be larger than the standard deviation of the observations. PMID:23466654

  10. Supplementation with spermine during in vitro maturation of porcine oocytes improves early embryonic development after parthenogenetic activation and somatic cell nuclear transfer.

    PubMed

    Jin, J X; Lee, S; Khoirinaya, C; Oh, A; Kim, G A; Lee, B C

    2016-03-01

    Spermine plays an important role in protection from reactive oxygen species (ROS) in bacteria, yeast, and mammalian cells, but there are few studies on the effects of spermine on porcine oocyte maturation and subsequent embryo development. The aim of this study was to determine the effects of spermine on in vitro maturation (IVM) of porcine oocytes and their developmental competence after parthenogenetic activation (PA) and somatic cell nuclear transfer (SCNT). We evaluated nuclear maturation, intracellular glutathione (GSH), and ROS levels in oocytes, and their subsequent embryonic development, as well as gene expression in mature oocytes, cumulus cells, and PA blastocysts. After treatment with various concentrations of spermine in IVM culture medium, there was no significant difference in nuclear maturation rate. However, spermine treatment groups (10- 500 µM) showed significantly increased intracellular GSH levels and decreased ROS levels compared to the control ( < 0.05). Furthermore, 10 µM spermine supported significantly higher blastocyst formation rates after PA than the control group ( < 0.05). According to the optimal condition from the PA results, we investigated the effects of 10 µM spermine on SCNT, and it also significantly improved blastocyst formation rates compared with the control group ( < 0.05). In evaluating the effects of 10 µM spermine on gene expression, there was significantly lower expression of a proapoptotic gene () and higher expression of an antiapoptotic gene () in cumulus cells ( < 0.05). was increased in spermine-treated oocytes. Levels of transcription for and were significantly increased in PA blastocysts. In conclusion, 10 µM spermine supplementation during IVM improved the development of porcine PA and SCNT embryos by increasing intracellular GSH, scavenging ROS levels, and regulating gene expression. PMID:27065258

  11. In vitro developmental competence of pig nuclear transferred embryos: effects of GFP transfection, refrigeration, cell cycle synchronization and shapes of donor cells.

    PubMed

    Zhang, Yun-Hai; Pan, Deng-Ke; Sun, Xiu-Zhu; Sun, Guo-Jie; Liu, Xiao-Hui; Wang, Xiao-Bo; Tian, Xing-Hua; Li, Yan; Dai, Yun-Ping; Li, Ning

    2006-08-01

    The present study was designed to evaluate the feasibility of producing pig transgenic blastocysts expressing enhanced green fluorescent protein (GFP) and to examine the effects of shape and preparation methods of donor cells on in vitro developmental ability of pig nuclear transferred embryos (NTEs). In experiment 1, the effect of GFP transfection on development of pig NTEs was evaluated. The cleavage and blastocyst rates showed no significant difference between NTEs derived from transfected and non-transfected donors. In experiment 2, the effect of different nuclear donor preparation methods on in vitro development of NTEs was examined. The cleavage rate showed no statistically significant differences among three preparation methods. The blastocyst rates of donor cells treated once at -4 degrees C and those of freshly digested cells were similar to each other (26.3% vs 17.9%). The lowest blastocyst rates (5.88%) were observed when cells cryopreserved at -196 degrees C were used as donors. In experiment 3, the effect of different cell cycle synchronization methods on the in vitro development potential of pig NTEs was evaluated. The cleavage rate of NTEs derived from cycling cells was much better than that of NTEs derived from serum-starved cells (64.4% vs 50.5%, p < 0.05), but no significant difference was observed between the the blastocyst rates of the two groups. In experiment 4, the effect of different shapes of cultured fibroblast cells on the in vitro development of pig NTEs was examined. The fusion rate for couplets derived from rough cells was poorer than that observed in couplets derived from round smooth cells (47.8% vs 76.8%, p < 0.05). However, there were no significant differences observed in the cleavage rate and blastocyst rate. In conclusion, the present study indicated that (i) refrigerated pig GFP-transfected cells could be used as donors in nuclear transfer and these NTEs could be effectively developed to blastocyst stage; (ii) serum starvation

  12. Seasonality and interspecies differences in particle/gas partitioning of PAHs observed by the Integrated Atmospheric Deposition Network (IADN)

    NASA Astrophysics Data System (ADS)

    Galarneau, Elisabeth; Bidleman, Terry F.; Blanchard, Pierrette

    This study presents partitioning data from eight locations in the Laurentian Great Lakes region collected by the Integrated Atmospheric Deposition Network (IADN) over periods ranging from 1 to 6 years. Particle/gas partitioning varies sufficiently between sites in the Great Lakes region to preclude the use of a uniform temperature dependence for its description. Site-specific parameters for describing partitioning as a function of inverse temperature are presented. Relationships between partitioning of appreciably semivolatile PAHs and saturated vapour pressure at Chicago (IIT) and Sturgeon Point (STP) demonstrate that anthracene, benz[a]anthracene and retene behave differently than phenanthrene, fluoranthene, pyrene and chrysene+triphenylene. Possible reasons for these differences include interspecies variations in the fraction of atmospherically non-exchangeable, though analytically extractable, PAHs on particles and differences in soot-air partition coefficients as they relate to saturated vapour pressure. The observed interspecies differences are not consistent with sampling artefacts such as filter adsorption or sorbent breakthrough. At IIT, but not at STP, values of the slope of the relationship between the log partition coefficient and log vapour pressure vary in a manner opposing the annual temperature cycle. A comparison of partitioning calculated by a combined absorption/adsorption model shows good predictability at Chicago but underestimates values at a rural site (Eagle Harbor, EGH) by an order of magnitude.

  13. Contrasting toxicokinetic evaluations and interspecies pharmacokinetic scaling approaches for small molecules and biologics: applicability to biosimilar development.

    PubMed

    Offman, Elliot; Edginton, Andrea N

    2013-06-01

    1. A 2-fold threshold typically used for prediction accuracy of interspecies scaling of clearance (CL) may be too liberal when using pharmacokinetic similarity in animals to advance biosimilar candidate selection for clinical testing. The purpose of this review is to identify interspecies scaling methods for use in de-risking biosimilar development prior to clinical testing. 2. Scaling approaches for predicting macromolecule CL were identified through literature review. Reports that evaluated predicted and observed human CLs for ≥5 individual compounds were considered. Absolute average fold-error (AAFE) was calculated for each method along with the proportion of compounds with individual fold-error values within a tighter threshold of 0.7-1.3. 3. Traditional simple allometry with a minimum of three species and the rule of exponents performed inconsistently with some groups of compounds resulting in a greater than 2-fold error (i.e. AAFE > 2). For monoclonal antibodies (mAbs), simplified allometric approaches employing a single species (monkey) with a fixed exponent of 0.85 consistently resulted in lower AAFEs and a higher proportion of compounds within the tighter range of 0.7-1.3. 4. For macromolecules, and particularly mAbs, employing single-species monkey "simplified" allometric approaches with a fixed exponent of 0.85 may be more appropriate than traditional allometric approaches. PMID:23244626

  14. Preliminary studies on model development for rodent toxicity and its interspecies correlation with aquatic toxicities of pharmaceuticals.

    PubMed

    Das, Rudra Narayan; Sanderson, Hans; Mwambo, Andrew E; Roy, Kunal

    2013-03-01

    Environmental toxicity due to pharmaceuticals has been an issue of serious concern for long time. Development of chemometric models with reliable predictive power has been considered as an effective tool for the design of new drug agents with reduced or without ecotoxic potential. Considering a higher degree of similarity in genetic homology towards drug receptor with mammals, we have used a dataset of 194 compounds with reported rodent, fish, daphnia and algae toxicity data for extrapolation of their toxicity towards humans. Allowing for rodents as the most surrogate to human physiology, attempts have also been made to develop interspecies correlation models keeping rodent toxicity as dependent variable so that any drug without reported rodent toxicity can be predicted using fish, daphnia or algae toxicity data which can be consequently extrapolated to human toxicity. The developed models have been subjected to multiple validation strategies. Acceptable results have been obtained in both cases of direct and interspecies extrapolation quantitative structure-activity relationship models. PMID:23238824

  15. Shielded cells transfer automation

    SciTech Connect

    Fisher, J J

    1984-01-01

    Nuclear waste from shielded cells is removed, packaged, and transferred manually in many nuclear facilities. Radiation exposure is absorbed by operators during these operations and limited only through procedural controls. Technological advances in automation using robotics have allowed a production waste removal operation to be automated to reduce radiation exposure. The robotic system bags waste containers out of glove box and transfers them to a shielded container. Operators control the system outside the system work area via television cameras. 9 figures.

  16. Transgenic cattle produced by nuclear transfer of fetal fibroblasts carrying Ipr1 gene at a specific locus.

    PubMed

    Wang, Yong Sheng; He, Xiaoning; Du, Yue; Su, Jianmin; Gao, Mingqing; Ma, Yefei; Hua, Song; Quan, Fusheng; Liu, Jun; Zhang, Yong

    2015-09-01

    This study aimed to assess the effects of the intracellular pathogen resistance 1 (Ipr1) transgene on preventing infection of Mycobacterium bovis in cattle. A specific expression vector for the Ipr1 gene was constructed and inserted in the genome between surfactant protein A and methionine adenosyltransferase I of bovine fetal fibroblasts. After SCNT, cleavage (86.9% vs. 87.4%, P > 0.05) and blastocyst developmental rates (34.6% vs. 33.5%, P > 0.05) were similar between transgenic and nontransgenic bovine fetal fibroblasts. Four surviving and one dead Ipr1-transgenic female cattle were produced by transfer of the SCNT blastocysts. Polymerase chain reaction and Southern blot analyses confirmed that the Ipr1 transgene of the cattle was located at the expected site. Inserting Ipr1 gene did not affect the expression of the surrounding genes. Main death modality of M bovis-infected peripheral blood mononuclear cells (PBMCs) derived from Ipr1-transgenic cattle was apoptosis, whereas that of PBMCs from control cattle was necrosis. In addition, the number of colony-forming units in PBMCs of Ipr1-transgenic cattle was significantly lower than that of the control cattle (P < 0.05). The finding that expression of Ipr1 transgene in PBMCs significantly increased anti-M bovis activity suggested breeding anti-M bovis cattle population by the transgenic SCNT technique could be a feasible strategy. PMID:25998271

  17. Heat transfer system

    DOEpatents

    McGuire, Joseph C.

    1982-01-01

    A heat transfer system for a nuclear reactor. Heat transfer is accomplished within a sealed vapor chamber which is substantially evacuated prior to use. A heat transfer medium, which is liquid at the design operating temperatures, transfers heat from tubes interposed in the reactor primary loop to spaced tubes connected to a steam line for power generation purposes. Heat transfer is accomplished by a two-phase liquid-vapor-liquid process as used in heat pipes. Condensible gases are removed from the vapor chamber through a vertical extension in open communication with the chamber interior.

  18. Heat transfer system

    DOEpatents

    Not Available

    1980-03-07

    A heat transfer system for a nuclear reactor is described. Heat transfer is accomplished within a sealed vapor chamber which is substantially evacuated prior to use. A heat transfer medium, which is liquid at the design operating temperatures, transfers heat from tubes interposed in the reactor primary loop to spaced tubes connected to a steam line for power generation purposes. Heat transfer is accomplished by a two-phase liquid-vapor-liquid process as used in heat pipes. Condensible gases are removed from the vapor chamber through a vertical extension in open communication with the chamber interior.

  19. APPLICATION OF A NOVEL RADIOIMMUNOASSAY TO IDENTIFY BACULOVIRUS STRUCTURAL PROTEINS THAT SHARE INTERSPECIES ANTIGENIC DETERMINANTS

    EPA Science Inventory

    Viral proteins were electrophoresed in polyacrylamide gels, transferred to nitrocellulose, and incubated with viral antisera, and the antibodies were detected with 125 I-labeled Staphylococcus aureus protein A. Antisera were prepared to purified and intact virions from five bacul...

  20. Comprehensive mollusk acute toxicity database improves the use of Interspecies Correlation Estimation (ICE) models to predict toxicity of untested freshwater and endangered mussel species

    EPA Science Inventory

    Interspecies correlation estimation (ICE) models extrapolate acute toxicity data from surrogate test species to untested taxa. A suite of ICE models developed from a comprehensive database is available on the US Environmental Protection Agency’s web-based application, Web-I...

  1. Three-year monitoring study of radiocesium transfer and ambient dose rate in forest environments affected by the Fukushima Dai-ichi Nuclear Power Plant accident

    NASA Astrophysics Data System (ADS)

    Kato, Hiroaki; Onda, Yuichi; Loffredo, Nicolas; Kawamori, Ayumi; Hisadome, Keigo

    2015-04-01

    We investigated the transfer of canopy-intercepted radiocesium to the forest floor during 3 years (July 2011~) following the Fukushima Dai-ichi Nuclear Power Plant accident. The cesium-137 (Cs-137) contents of throughfall, stemflow, and litterfall were monitored in two coniferous stands (plantation of Japanese cedar) and a deciduous broad-leaved forest stand (Japanese oak with red pine). We also measured an ambient dose rate at different height in the forest by using a survey meter (TCS-172B, Hitachi-Aloka Medical, LTD.) and a portable Ge gamma-ray detector (Detective-DX-100T, Ortec, Ametek, Inc.). Furthermore, effects of forest decontamination on the reduction of ambient dose rate were assessed quantitatively. Total Cs-137 deposition flux from the canopy to forest floor for the mature cedar, young cedar, and the mixed broad-leaved stands were 157 kBq/m^2, 167 kBq/m^2, and 54 kBq/m^2, respectively. These values correspond to 36%, 39% and 12% of total atmospheric input after the accident. The ambient dose rate showed an exponential decrease with time for all the forest sites, however the decreasing trend differed depending on the forest type. These data suggested that an ambient dose rate in forest environment can be variable in spatially and temporally reflecting the transfer of radiocesium from canopy to forest floor. We presented the analysis results of the relationship between radiocesium deposition flux and ambient dose rate at the forest floor. In addition to that, we reported the effects of forest decontamination (e.g., tree felling, removal of organic materials, woodchip pavement) on the reduction of ambient dose rate in the forest environment.

  2. Transfer of 137Cs and 134Cs from litter into soil's of Japanese cypress forest after Fukushima nuclear accident in Karasawayama catchment, Tochigi prefecture

    NASA Astrophysics Data System (ADS)

    Mengistu, T. T.; Onda, Y.; Kato, H.; Gomi, T.

    2011-12-01

    The mega earthquake that rampaged north-east Japan on March 11, 2011 and the triggered subsequent tsunami hit the Fukushima Daiichi Nuclear power plant and resulted the discharge of about 770,000 terabecquerel radionuclide materials to the atmosphere. The distribution and deposition of the radionucides are then governed by the wind and rain following the release. When the cloud of radionuclide material by-pass the forest ecosystem (as radiodust-sinker), radionuclides are trapped and deposited to the forest floor through dry, litter, wet depositions. Litter-fall, as a key process of nutrient cycling in forest ecosystem, plays a great role in transferring canopy-trapped radionuclides to the forest soil. And so, we are monitoring the of Fukushima derived 137Cs deposition rate through litter to forest soil's of Japanese cypress(Chamaecyparis obutsa Sieb.et Zucc.) forests located approximately 160 km from the crippled nuclear power plant. For this purpose, five litter traps (1m2 areas each) were set up at one meter above the ground in the forest stand at the end of March 2011. Fukushima-derived 137Cs is then estimated from 134Cs:137Cs ratio as all 134Cs is originated from Fukushima. Within the two months of the accident, mean 134Cs:137Cs ratio was 0.8 in cypress litter. The inventories of both 137Cs and 134Cs in the upper 2cm forest soil were found 5089 Bq m-2 and 3571 Bq m-2, respectively. As a result, the amount of Fukushima-derived 137Cs deposition in upper 2cm soil layer by cypress litter is 4464 Bq m-2. This value account 88% of the total inventories of 137Cs in the upper 2cm soils and the other depositional paths (dry and wet fall) including old 137Cs cover only 12%. The transfer rate of 137Cs and 134Cs from canopy-litter to soil could be depend on litter's radionuclide adsorption strength (canopy and leaves architecture), the rate, amount of litter fall and its residence time in the canopy and forest floor. However, the results strongly confirmed that litter is

  3. A highly efficient method for generation of therapeutic quality human pluripotent stem cells by using naive induced pluripotent stem cells nucleus for nuclear transfer

    PubMed Central

    2014-01-01

    Even after several years since the discovery of human embryonic stem cells and induced pluripotent stem cells (iPSC), we are still unable to make any significant therapeutic benefits out of them such as cell therapy or generation of organs for transplantation. Recent success in somatic cell nuclear transfer (SCNT) made it possible to generate diploid embryonic stem cells, which opens up the way to make high-quality pluripotent stem cells. However, the process is highly inefficient and hence expensive compared to the generation of iPSC. Even with the latest SCNT technology, we are not sure whether one can make therapeutic quality pluripotent stem cell from any patient’s somatic cells or by using oocytes from any donor. Combining iPSC technology with SCNT, that is, by using the nucleus of the candidate somatic cell which got reprogrammed to pluripotent state instead that of the unmodified nucleus of the candidate somatic cell, would boost the efficiency of the technique, and we would be able to generate therapeutic quality pluripotent stem cells. Induced pluripotent stem cell nuclear transfer (iPSCNT) combines the efficiency of iPSC generation with the speed and natural reprogramming environment of SCNT. The new technique may be called iPSCNT. This technique could prove to have very revolutionary benefits for humankind. This could be useful in generating organs for transplantation for patients and for reproductive cloning, especially for childless men and women who cannot have children by any other techniques. When combined with advanced gene editing techniques (such as CRISPR-Cas system) this technique might also prove useful to those who want to have healthy children but suffer from inherited diseases. The current code of ethics may be against reproductive cloning. However, this will change with time as it happened with most of the revolutionary scientific breakthroughs. After all, it is the right of every human to have healthy offspring and it is the question of

  4. Scriptaid Treatment Decreases DNA Methyltransferase 1 Expression by Induction of MicroRNA-152 Expression in Porcine Somatic Cell Nuclear Transfer Embryos

    PubMed Central

    Liang, Shuang; Zhao, Ming-Hui; Choi, Jeong-woo; Kim, Nam-Hyung; Cui, Xiang-Shun

    2015-01-01

    Abnormal epigenetic reprogramming of donor nuclei after somatic cell nuclear transfer (SCNT) is thought to be the main cause of low cloning efficiencies. A growing body of evidence has demonstrated a positive role of Scriptaid, a histone deacetylase inhibitor (HDACi) that belongs to an existing class of hydroxamic acid-containing HDACis, on the development competence of cloned embryos in many species. The present study investigated the effects of Scriptaid on the development of porcine SCNT embryos in vitro and its mechanism. Treatment with 300 or 500 nM Scriptaid for 20 h after activation significantly increased the percentage of SCNT embryos that developed to the blastocyst stage and the total number of cells per blastocyst and significantly decreased the percentage of apoptotic cells in blastocysts. Scriptaid treatment significantly increased the level of histone H3 acetylated at K9 and the conversion of 5-methylcytosine into 5-hydroxymethylcytosine and significantly decreased the level of histone H3 trimethylated at K9 at the pronuclear stage. As a potential mechanism for the DNA methylation changes, our results showed that the expression of DNA methyltransferase 1 was frequently down-regulated in Scriptaid-treated embryos in comparison with untreated embryos and was inversely correlated to endogenous microRNA-152 (miR-152). Taken together, these findings illustrated a crucial functional crosstalk between miR-152 and DNMT1. Meanwhile, mRNA and protein levels of POU5F1 and CDX2 were increased in Scriptaid-treated embryos. mRNA levels of Caspase3, and Bax were significantly decreased and that of Bcl-xL was significantly increased in Scriptaid-treated embryos. In conclusion, these observations would contribute to uncover the nuclear reprogramming mechanisms underlying the effects of Scriptaid on the improvement of porcine SCNT embryos. PMID:26261994

  5. Tracking interspecies transmission and long-term evolution of an ancient retrovirus using the genomes of modern mammals.

    PubMed

    Diehl, William E; Patel, Nirali; Halm, Kate; Johnson, Welkin E

    2016-01-01

    Mammalian genomes typically contain hundreds of thousands of endogenous retroviruses (ERVs), derived from ancient retroviral infections. Using this molecular 'fossil' record, we reconstructed the natural history of a specific retrovirus lineage (ERV-Fc) that disseminated widely between ~33 and ~15 million years ago, corresponding to the Oligocene and early Miocene epochs. Intercontinental viral spread, numerous instances of interspecies transmission and emergence in hosts representing at least 11 mammalian orders, and a significant role for recombination in diversification of this viral lineage were also revealed. By reconstructing the canonical retroviral genes, we identified patterns of adaptation consistent with selection to maintain essential viral protein functions. Our results demonstrate the unique potential of the ERV fossil record for studying the processes of viral spread and emergence as they play out across macro-evolutionary timescales, such that looking back in time may prove insightful for predicting the long-term consequences of newly emerging viral infections. PMID:26952212

  6. Role of interspecies interactions in the preparation of a low-entropy gas of polar molecules in a lattice

    NASA Astrophysics Data System (ADS)

    Safavi-Naini, A.; Wall, M. L.; Rey, A. M.

    2015-12-01

    The preparation of a quantum degenerate gas of heteronuclear molecules has been an outstanding challenge. We use path-integral quantum Monte Carlo simulations to understand the role of interactions and finite temperature effects in the protocol currently employed to adiabatically prepare a low-entropy gas of polar molecules in a lattice starting from an ultracold Bose-Fermi mixture. We find that interspecies interactions affect the final temperature of the mixture after the adiabatic loading procedure and detrimentally limit the molecular peak filling. Our conclusions are in agreement with recent experimental measurements [Moses et al., Science 350, 659 (2015), 10.1126/science.aac6400] and therefore are of immediate relevance for the myriad experiments that aim to form molecules from dual-species atomic gases.

  7. Beyond the Whole-Genome Duplication: Phylogenetic Evidence for an Ancient Interspecies Hybridization in the Baker's Yeast Lineage

    PubMed Central

    Marcet-Houben, Marina; Gabaldón, Toni

    2015-01-01

    Whole-genome duplications have shaped the genomes of several vertebrate, plant, and fungal lineages. Earlier studies have focused on establishing when these events occurred and on elucidating their functional and evolutionary consequences, but we still lack sufficient understanding of how genome duplications first originated. We used phylogenomics to study the ancient genome duplication occurred in the yeast Saccharomyces cerevisiae lineage and found compelling evidence for the existence of a contemporaneous interspecies hybridization. We propose that the genome doubling was a direct consequence of this hybridization and that it served to provide stability to the recently formed allopolyploid. This scenario provides a mechanism for the origin of this ancient duplication and the lineage that originated from it and brings a new perspective to the interpretation of the origin and consequences of whole-genome duplications. PMID:26252497

  8. Detection of Salmonella enterica in Magellanic penguins (Spheniscus magellanicus) of Chilean Patagonia: evidences of inter-species transmission.

    PubMed

    Dougnac, C; Pardo, C; Meza, K; Arredondo, C; Blank, O; Abalos, P; Vidal, R; Fernandez, A; Fredes, F; Retamal, P

    2015-04-01

    Patagonia in southern South America is among the few world regions where direct human impact is still limited but progressively increasing, mainly represented by tourism, farming, fishing and mining activities. The sanitary condition of Patagonian wildlife is unknown, in spite of being critical for the assessment of anthropogenic effects there. The aim of this study was the characterization of Salmonella enterica strains isolated from wild colonies of Magellanic penguins (Spheniscus magellanicus) located in Magdalena Island and Otway Sound, in Chilean Patagonia. Eight isolates of Salmonella were found, belonging to Agona and Enteritidis serotypes, with an infection rate of 0·38%. Resistance to ampicillin, cefotaxime, ceftiofur and tetracycline antimicrobials were detected, and some of these strains showed genotypic similarity with Salmonella strains isolated from humans and gulls, suggesting inter-species transmission cycles and strengthening the role of penguins as sanitary sentinels in the Patagonian ecosystem. PMID:25148565

  9. Beyond the Whole-Genome Duplication: Phylogenetic Evidence for an Ancient Interspecies Hybridization in the Baker's Yeast Lineage.

    PubMed

    Marcet-Houben, Marina; Gabaldón, Toni

    2015-08-01

    Whole-genome duplications have shaped the genomes of several vertebrate, plant, and fungal lineages. Earlier studies have focused on establishing when these events occurred and on elucidating their functional and evolutionary consequences, but we still lack sufficient understanding of how genome duplications first originated. We used phylogenomics to study the ancient genome duplication occurred in the yeast Saccharomyces cerevisiae lineage and found compelling evidence for the existence of a contemporaneous interspecies hybridization. We propose that the genome doubling was a direct consequence of this hybridization and that it served to provide stability to the recently formed allopolyploid. This scenario provides a mechanism for the origin of this ancient duplication and the lineage that originated from it and brings a new perspective to the interpretation of the origin and consequences of whole-genome duplications. PMID:26252497

  10. Paddy-field contamination with 134Cs and 137Cs due to Fukushima Dai-ichi Nuclear Power Plant accident and soil-to-rice transfer coefficients.

    PubMed

    Endo, Satoru; Kajimoto, Tsuyoshi; Shizuma, Kiyoshi

    2013-02-01

    The transfer coefficient (TF) from soil to rice plants of (134)Cs and (137)Cs in the form of radioactive deposition from the Fukushima Dai-ichi Nuclear Power Plant (FDNPP) accident in March 2011 was investigated in three rice paddy fields in Minami-Soma City. Rice crops were planted in the following May and harvested at the end of September. Soil cores of 30-cm depth were sampled from rice-planted paddy fields to measure (134)Cs and (137)Cs radioactivity at 5-cm intervals. (134)Cs and (137)Cs radioactivity was also measured in rice ears (rice with chaff), straws and roots. The rice ears were subdivided into chaff, brown rice, polished rice and rice bran, and the (134)Cs and (137)Cs radioactivity concentration of each plant part was measured to calculate the respective TF from the soil. The TF of roots was highest at 0.48 ± 0.10 in the field where the (40)K concentration in the soil core was relatively low, in comparison with TF values of 0.31 and 0.38 in other fields. Similar trends could be found for the TF of whole rice plants, excluding roots. The TF of rice ears was relatively low at 0.019-0.026. The TF of chaff, rice bran, brown rice and polished rice was estimated to be 0.049, 0.10-0.16, 0.013-0.017 and 0.005-0.013, respectively. PMID:23103577

  11. The structure of a ring-opened proliferating cell nuclear antigen–replication factor C complex revealed by fluorescence energy transfer

    PubMed Central

    Zhuang, Zhihao; Yoder, Bonita L.; Burgers, Peter M. J.; Benkovic, Stephen J.

    2006-01-01

    Numerous proteins that function in DNA metabolic pathways are known to interact with the proliferating cell nuclear antigen (PCNA). The important function of PCNA in stimulating various cellular activities requires its topological linkage with DNA. Loading of the circular PCNA onto duplex DNA requires the activity of a clamp-loader [replication factor C (RFC)] complex and the energy derived from ATP hydrolysis. The mechanistic and structural details regarding PCNA loading by the RFC complex are still developing. In particular, the positive identification of a long-hypothesized structure of an open clamp–RFC complex as an intermediate in loading has remained elusive. In this study, we capture an open yeast PCNA clamp in a complex with RFC through fluorescence energy transfer experiments. We also follow the topological transitions of PCNA in the various steps of the clamp-loading pathway through both steady-state and stopped-flow fluorescence studies. We find that ATP effectively drives the clamp-loading process to completion with the formation of the closed PCNA bound to DNA, whereas ATPγS cannot. The information derived from this work complements that obtained from previous structural and mechanistic studies and provides a more complete picture of a eukaryotic clamp-loading pathway using yeast as a paradigm. PMID:16476998

  12. Distinct dendritic spine and nuclear phases of calcineurin activation after exposure to amyloid-β revealed by a novel fluorescence resonance energy transfer assay.

    PubMed

    Wu, Hai-Yan; Hudry, Eloise; Hashimoto, Tadafumi; Uemura, Kengo; Fan, Zhan-Yun; Berezovska, Oksana; Grosskreutz, Cynthia L; Bacskai, Brian J; Hyman, Bradley T

    2012-04-11

    Calcineurin (CaN) activation is critically involved in the regulation of spine morphology in response to oligomeric amyloid-β (Aβ) as well as in synaptic plasticity in normal memory, but no existing techniques can monitor the spatiotemporal pattern of CaN activity. Here, we use a spectral fluorescence resonance energy transfer approach to monitor CaN activation dynamics in real time with subcellular resolution. When oligomeric Aβ derived from Tg2576 murine transgenic neurons or human AD brains were applied to wild-type murine primary cortical neurons, we observe a dynamic progression of CaN activation within minutes, first in dendritic spines, and then in the cytoplasm and, in hours, in the nucleus. CaN activation in spines leads to rapid but reversible morphological changes in spines and in postsynaptic proteins; longer exposure leads to NFAT (nuclear factor of activated T-cells) translocation to the nucleus and frank spine loss. These results provide a framework for understanding the role of calcineurin in synaptic alterations associated with AD pathogenesis. PMID:22496575

  13. Telomere elongation and naïve pluripotent stem cells achieved from telomerase haplo-insufficient cells by somatic cell nuclear transfer

    PubMed Central

    Sung, Li-Ying; Chang, Wei-Fang; Zhang, Qian; Liu, Chia-Chia; Liou, Jun-Yang; Chang, Chia-Chun; Ou-Yang, Huan; Guo, Renpeng; Fu, Haifeng; Cheng, Winston T.K.; Ding, Shih-Torng; Chen, Chuan-Mu; Okuka, Maja; Keefe, David L; Chen, Y. Eugene; Liu, Lin; Xu, Jie

    2014-01-01

    Haplo-insufficiency of telomerase genes in humans leads to telomere syndromes such as dyskeratosis congenital and idiopathic pulmonary fibrosis. Generation of pluripotent stem cells from telomerase haplo-insufficient donor cells would provide unique opportunities towards the realization of patient-specific stem cell therapies. Recently, pluripotent human embryonic stem cells (ntESCs) have been efficiently achieved by somatic cell nuclear transfer (SCNT). We tested the hypothesis that SCNT could effectively elongate shortening telomeres of telomerase haplo-insufficient cells in the ntESCs using relevant mouse models. Indeed, telomeres of telomerase haplo-insufficient (Terc+/−) mouse cells are elongated in ntESCs. Moreover, ntESCs derived from Terc+/− cells exhibit naïve pluripotency as evidenced by generation of Terc+/−ntESC clone pups by tetraploid embryo complementation (TEC), the most stringent test of naïve pluripotency. These data suggest that SCNT could offer a powerful tool to reprogram telomeres and to discover the factors for robust restoration of telomeres and pluripotency of telomerase haplo-insufficient somatic cells. PMID:25464850

  14. Loss of Methylation at H19 DMD Is Associated with Biallelic Expression and Reduced Development in Cattle Derived by Somatic Cell Nuclear Transfer1

    PubMed Central

    Suzuki, J.; Therrien, J.; Filion, F.; Lefebvre, R.; Goff, A.K.; Perecin, F.; Meirelles, F.V.; Smith, L.C.

    2011-01-01

    Although cloning of mammals has been achieved successfully, the percentage of live offspring is very low because of reduced fetal size and fewer implantation sites. Recent studies have attributed such pathological conditions to abnormal reprogramming of the donor cell used for cloning. The inability of the oocyte to fully restore the differentiated status of a somatic cell to its pluripotent and undifferentiated state is normally evidenced by aberrant DNA methylation patterns established throughout the genome during development to blastocyst. These aberrant methylation patterns are associated with abnormal expression of imprinted genes, which among other genes are essential for normal embryo development and gestation. We hypothesized that embryo loss and low implantation rates in cattle derived by somatic cell nuclear transfer (SCNT) are caused by abnormal epigenetic reprogramming of imprinted genes. To verify our hypothesis, we analyzed the parental expression and the differentially methylated domain (DMD) methylation status of the H19 gene. Using a parental-specific analysis, we confirmed for the first time that H19 biallelic expression is tightly associated with a severe demethylation of the paternal H19 DMD in SCNT embryos, suggesting that these epigenetic anomalies to the H19 locus could be directly responsible for the reduced size and low implantation rates of cloned embryos in cattle. PMID:21248292

  15. Risk and prevention of bovine viral diarrhea virus (BVDV) transmission through embryo production via somatic cell nuclear transfer (SCNT) using oocytes from persistently infected donors.

    PubMed

    Gregg, K; Riddell, K P; Chen, S H; Galik, P K; Xiang, T; Guerra, T; Marley, M S; Polejaeva, I; Givens, M D

    2010-07-01

    The objective was to assess the risk of transmission of bovine viral diarrhea virus (BVDV) through embryo production via somatic cell nuclear transfer (SCNT), with oocytes obtained from persistently infected (PI) donors. Using ultrasound-guided follicular aspiration following superstimulation, oocytes were obtained from five female beef cattle, including three that were PI and two that were negative for BVDV. In the three PI cattle, seven aspirations yielded 32 oocytes (PI-1: three aspirations yielding six oocytes; PI-2: two aspirations yielding 14 oocytes; and PI-3: two aspirations yielding 12 oocytes). The oocyte recovery rate was better in negative control cattle, with 32 oocytes obtained from the two cattle in a single superstimulation and aspiration session. Oocytes were processed individually for SCNT, evaluated, and tested for BVDV. Nearly all (31/32) oocytes from the three PI donors were positive for BVDV by PCR, with detected viral RNA copy number ranging from 1 to 1.1 x 10(5). The proportion of oocytes acceptable for SCNT embryo production (based on oocyte quality and maturation status) was only 16 to 35% from PI donors, but was 81% from control donors. Therefore, routine testing of unacceptable (discarded) oocytes could be an effective approach to identify batches that might contain infected oocytes from PI donors. Identification and removal of high-risk batches of oocytes would minimize the risk of BVDV transmission through SCNT embryo production. PMID:20188405

  16. Generation of liver-specific TGF-α/c-Myc-overexpressing porcine induced pluripotent stem-like cells and blastocyst formation using nuclear transfer.

    PubMed

    Park, Kyung-Mee; Lee, Joohyeong; Hussein, Kamal Hany; Hong, Seok-Ho; Yang, Se-Ran; Lee, Eunsong; Woo, Heung-Myong

    2016-05-01

    Transgenic porcine induced pluripotent stem (iPS) cells are attractive cell sources for the development of genetically engineered pig models, because they can be expanded without senescence and have the potential for multiple gene manipulation. They are also useful cell sources for disease modeling and treatment. However, the generation of transgenic porcine iPS cells is rare, and their embryonic development after nuclear transfer (NT) has not yet been reported. We report here the generation of liver-specific oncogenes (TGF-α/c-Myc)-overexpressing porcine iPS (T/M iPS)-like cells. They expressed stem cell characteristics and were differentiated into hepatocyte-like cells that express oncogenes. We also confirmed that NT embryos derived from T/M iPS-like cells successfully developed blastocysts in vitro. As an initial approach toward porcine transgenic iPS cell generation and their developmental competence after NT, this study provides foundations for the efficient generation of genetically modified porcine iPS cells and animal models. PMID:26725870

  17. Generation of liver-specific TGF-α/c-Myc-overexpressing porcine induced pluripotent stem-like cells and blastocyst formation using nuclear transfer

    PubMed Central

    PARK, Kyung-Mee; LEE, Joohyeong; HUSSEIN, Kamal Hany; HONG, Seok-Ho; YANG, Se-Ran; LEE, Eunsong; WOO, Heung-Myong

    2015-01-01

    Transgenic porcine induced pluripotent stem (iPS) cells are attractive cell sources for the development of genetically engineered pig models, because they can be expanded without senescence and have the potential for multiple gene manipulation. They are also useful cell sources for disease modeling and treatment. However, the generation of transgenic porcine iPS cells is rare, and their embryonic development after nuclear transfer (NT) has not yet been reported. We report here the generation of liver-specific oncogenes (TGF-α/c-Myc)-overexpressing porcine iPS (T/M iPS)-like cells. They expressed stem cell characteristics and were differentiated into hepatocyte-like cells that express oncogenes. We also confirmed that NT embryos derived from T/M iPS-like cells successfully developed blastocysts in vitro. As an initial approach toward porcine transgenic iPS cell generation and their developmental competence after NT, this study provides foundations for the efficient generation of genetically modified porcine iPS cells and animal models. PMID:26725870

  18. Production of transgenic goats expressing human coagulation factor IX in the mammary glands after nuclear transfer using transfected fetal fibroblast cells.

    PubMed

    Amiri Yekta, Amir; Dalman, Azam; Eftekhari-Yazdi, Poopak; Sanati, Mohammad Hossein; Shahverdi, Abdol Hossein; Fakheri, Rahman; Vazirinasab, Hamed; Daneshzadeh, Mohammad Taghi; Vojgani, Mahdi; Zomorodipour, Alireza; Fatemi, Nayeralsadat; Vahabi, Zeinab; Mirshahvaladi, Shahab; Ataei, Fariba; Bahraminejad, Elmira; Masoudi, Najmehsadat; Rezazadeh Valojerdi, Mojtaba; Gourabi, Hamid

    2013-02-01

    There are growing numbers of recombinant proteins that have been expressed in milk. Thus one can consider the placement of any gene of interest under the control of the regulatory elements of a milk protein gene in a dairy farm animal. Among the transgene introducing techniques, only nuclear transfer (NT) allows 100 % efficiency and bypasses the mosaicism associated with counterpart techniques. In this study, in an attempt to produce a transgenic goat carrying the human coagulation factor IX (hFIX) transgene, goat fetal fibroblasts were electroporated with a linearized marker-free construct in which the transgene was juxtaposed to β-casein promoter designed to secret the recombinant protein in goat milk. Two different lines of transfected cells were used as donors for NT to enucleated oocytes. Two transgenic goats were liveborn. DNA sequencing of the corresponding transgene locus confirmed authenticity of the cloning procedure and the complementary experiments on the whey demonstrated expression of human factor IX in the milk of transgenic goats. In conclusion, our study has provided the groundwork for a prosperous and promising approach for large-scale production and therapeutic application of hFIX expressed in transgenic goats. PMID:22869287

  19. Temperature-scanned magnetic resonance and the evidence of two-way transfer of a nitrogen nuclear spin hyperfine interaction in coupled NV-N pairs in diamond

    NASA Astrophysics Data System (ADS)

    Babunts, R. A.; Soltamova, A. A.; Tolmachev, D. O.; Soltamov, V. A.; Gurin, A. S.; Anisimov, A. N.; Preobrazhenskii, V. L.; Baranovi, P. G.

    2012-06-01

    New method for the detection of magnetic resonance signals versus temperature is developed on the basis of the temperature dependence of the spin Hamiltonian parameters of the paramagnetic system under investigation. The implementation of this technique is demonstrated on the nitrogen-vacancy (NV) centers in diamonds. Single NV defects and their ensembles are suggested to be almost inertialess temperature sensors. The hyperfine structure of the 14N nitrogen nuclei of the nitrogen-vacancy center appears to be resolved in the hyperfine structure characteristic of the hyperfine interaction between NV and an N s center (substitutional nitrogen impurity) in the optically detected magnetic resonance spectra of the molecular NV-N s complex. Thus, we show that a direct evidence of the two-way transfer of a nitrogen nuclear spin hyperfine interaction in coupled NV-N s pairs was observed. It is shown that more than 3-fold enhancement of the NV optically detected magnetic resonance signal can be achieved by using water as a collection optics medium.

  20. Aqueous and tissue residue-based interspecies correlation estimation models provide conservative hazard estimates for aromatic compounds.

    PubMed

    Bejarano, Adriana C; Barron, Mace G

    2016-01-01

    Interspecies correlation estimation (ICE) models were developed for 30 nonpolar aromatic compounds to allow comparison of prediction accuracy between 2 data compilation approaches. Type 1 models used data combined across studies, and type 2 models used data combined only within studies. Target lipid (TLM) ICE models were also developed using target lipid concentrations of the type 2 model dataset (type 2-TLM). Analyses were performed to assess model prediction uncertainty introduced by each approach. Most statistically significant models (90%; 266 models total) had mean square errors < 0.27 and adjusted coefficients of determination (adj R(2) ) > 0.59, with the lowest amount of variation in mean square errors noted for type 2-TLM followed by type 2 models. Cross-validation success (>0.62) across most models (86% of all models) confirmed the agreement between ICE predicted and observed values. Despite differences in model predictive ability, most predicted values across all 3 ICE model types were within a 2-fold difference of the observed values. As a result, no statistically significant differences (p > 0.05) were found between most ICE-based and empirical species sensitivity distributions (SSDs). In most cases hazard concentrations were within or below the 95% confidence intervals of the direct-empirical SSD-based values, regardless of model choice. Interspecies correlation estimation-based 5th percentile (HC5) values showed a 200- to 900-fold increase as the log KOW increased from 2 to 5.3. Results indicate that ICE models for aromatic compounds provide a statistically based approach for deriving conservative hazard estimates for protecting aquatic life. PMID:26184086

  1. Inter-species and Seasonal Variability in Mg / Ca in Larger Benthic Foraminifera: Implications for Paleo-proxy

    NASA Astrophysics Data System (ADS)

    Singh, A.; Saraswati, P. K.; Pande, K.; Sanyal, P.

    2015-12-01

    The reports of inter-species variability to intra-test heterogeneity in Mg/Ca in several species of foraminifera have raised question about its use in estimation of seawater temperatures and necessitate field and culture studies to verify it for species from different habitats. In this study, we attempt to investigate if Mg/Ca in larger benthic foraminifera (LBF) could be a potential proxy of seawater temperatures for shallow marine carbonates. The samples were collected in different seasons from coral reef at Akajima (Okinawa, Japan). The Ca and Mg of 13 species of LBF and small benthic foraminifera from the same season were determined to examine variation in Mg/Ca among the species calcified under presumably the same temperature and salinity conditions. We also analyzed Amphistegina lessoni from different seasons for Ca, Mg and δ18O to determine variation in Mg/Ca with temperature and see how the two proxies of temperatures, Mg/Ca and δ18O, correlate in the same species. The species cluster about two distinctly separated Mg/Ca values. The first group comprising species of Amphistegina, Gypsina, Ammonia and Elphidium have relatively lower Mg/Ca, varying from 30 to 45 mmol/mol. The second group, having average Mg/Ca ranging from ~110 to 170 mmol/mol, includes species of Schlumbergerella, Baculogypsinoides, Baculogypsina, Heterostegina, Operculina, Calcarina, Amphisorus, Alveolinella and Poroeponides. The result suggests large interspecies variability implying vital effect in foraminiferal Mg/Ca. There is no distinct difference in Mg/Ca values between porcelaneous and hyaline types or symbiont-bearing and symbiont-free types. In Amphistegina lessoni the variation in Mg/Ca between individuals of the same season is as large as variation across the seasons. There is no correlation between Mg/Ca and seawater temperature. Lack of correlation between Mg/Ca and δ18O further suggests that Mg/Ca in the species is not primarily controlled by temperature.

  2. Interspecies variability in expression of hepatobiliary transporters across human, dog, monkey, and rat as determined by quantitative proteomics.

    PubMed

    Wang, Li; Prasad, Bhagwat; Salphati, Laurent; Chu, Xiaoyan; Gupta, Anshul; Hop, Cornelis E C A; Evers, Raymond; Unadkat, Jashvant D

    2015-03-01

    We quantified, by liquid chromatography tandem mass spectrometry, transporter protein expression of BSEP, MATE1, MRP3, MRP4, NTCP, and OCT1 in our human liver bank (n = 55) and determined the relationship between protein expression and sex, age and genotype. These data complement our previous work in the same liver bank where we quantified the protein expression of OATPs, BCRP, MDR1, and MRP2. In addition, we quantified and compared the interspecies differences in expression of the hepatobiliary transporters, corresponding to the above human transporters, in liver tissue and hepatocytes of male beagle dogs, cynomolgus monkeys, Sprague-Dawley rats, and Wistar rats. In all the species, the sinusoidal OATPs/Oatps were the most abundant hepatic transporters. However, there were notable interspecies differences in the relative abundance of the remaining transporters. For example, the next most abundant transporter in humans and monkeys was OCT1/Oct1, whereas it was Mrp2 and Ntcp in dogs/Wistar rats and Sprague-Dawley rats, respectively. In contrast, the protein expression of the efflux transporters BCRP/Bcrp, MDR1/Mdr1, MRP3/Mrp3, MRP4/Mrp4, and MATE1/Mate1 was much lower across all the species. For most transporters, the expression in the liver tissues was comparable to that in the unplated cryopreserved hepatocytes. These data on human liver transporter protein expression complete the picture of the expression of major human hepatobiliary transporters important in drug disposition and toxicity. In addition, the data on expression of the corresponding hepatobiliary transporters in preclinical species will be helpful in interpreting and extrapolating pharmacokinetic, pharmacological, and toxicological results from preclinical studies to humans. PMID:25534768

  3. Kinetic evidence for the formation of discrete 1,4-dehydrobenzene intermediates. Trapping by inter- and intramolecular hydrogen atom transfer and observation of high-temperature CIDNP (chemically induced dynamic nuclear polarization). [Chemically induced dynamic nuclear polarization

    SciTech Connect

    Lockhart, T.P.; Comita, P.B.; Bergman, R.G.

    1981-07-15

    Upon being heated, alkyl-substituted cis-1,2-diethynyl olefins undergo cyclization to yield reactive 1,4-dehydrobenzenes; the products isolated may be derived from either unimolecular or bimolecular reactions of the intermediate. (Z)-4,5-Diethynyl-4-octene (4) undergoes rearrangement to yield 2,3-di-n-propyl-1,4-dehydrobenzene (17). Solution pyrolysis of 4 in inert aromatic solvents produces three unimolecular products, (Z)-dodeca-4,8-diyn-6-ene (7), benzocycloctene (9), and o-allyl-n-propylbenzene (10), in high yield. When 1,4-cyclohexadiene is added to the pyrolysis solution as a trapping agent high yields of the reduced product o-di-n-propylbenzene (12) are obtained. The kinetics of solution pyrolysis of 4 in the presence and absence of trapping agent pyl-1,4-dehydrobenzene is a discrete intermediate on the pathway leading to products. When the reaction was run in the heated probe of an NMR spectrometer, chemically induced dynamic nuclear polarization was observed in 10. This observation, along with kinetic and chemical trapping evidence, indicates the presence of two additional intermediates, formed from 17 by sequential intramolecular (1,5) hydrogen transfer, on the pathway to products. The observation of CIDNP, coupled with the reactivity exhibited by 17 and the other two intermediates, implicates a biradical description of these molecules.

  4. Heat transfer in energy problems

    NASA Astrophysics Data System (ADS)

    Mizushina, T.; Yang, W. J.

    Results of recent research are presented concerning heat transfer in energy problems, including high-temperature heat transfer, high-flux heat transfer, high-performance heat transfer, heat transfer in nonconventional energy (power and propulsion) systems, and novel heat transfer techniques. Topics discussed include studies of full-coverage film cooling, radiative properties of metals and alloys at high temperature, critical heat flux conditions in high-quality boiling systems, heat transfer characteristics of the evaporation of a liquid droplet on heated surfaces, high-performance surfaces for non-boiling heat transfer, and high performance heat transfer surfaces for boiling and condensation. Also examined are high flux heat transfer in gaseous solid suspension flow, nuclear process heat applications of high temperature heat exchange, heat transfer considerations in the use of new energy resources, and high performance mist-cooled condensers for geothermal binary cycle plants. No individual items are abstracted in this volume

  5. Experimental investigations of heat transfer and temperature fields in models simulating fuel assemblies used in the core of a nuclear reactor with a liquid heavy-metal coolant

    NASA Astrophysics Data System (ADS)

    Belyaev, I. A.; Genin, L. G.; Krylov, S. G.; Novikov, A. O.; Razuvanov, N. G.; Sviridov, V. G.

    2015-09-01

    The aim of this experimental investigation is to obtain information on the temperature fields and heat transfer coefficients during flow of liquid-metal coolant in models simulating an elementary cell in the core of a liquid heavy metal cooled fast-neutron reactor. Two design versions for spacing fuel rods in the reactor core were considered. In the first version, the fuel rods were spaced apart from one another using helical wire wound on the fuel rod external surface, and in the second version spacer grids were used for the same purpose. The experiments were carried out on the mercury loop available at the Moscow Power Engineering Institute National Research University's Chair of Engineering Thermal Physics. Two experimental sections simulating an elementary cell for each of the fuel rod spacing versions were fabricated. The temperature fields were investigated using a dedicated hinged probe that allows temperature to be measured at any point of the studied channel cross section. The heat-transfer coefficients were determined using the wall temperature values obtained at the moment when the probe thermocouple tail end touched the channel wall. Such method of determining the wall temperature makes it possible to alleviate errors that are unavoidable in case of measuring the wall temperature using thermocouples placed in slots milled in the wall. In carrying out the experiments, an automated system of scientific research was applied, which allows a large body of data to be obtained within a short period of time. The experimental investigations in the first test section were carried out at Re = 8700, and in the second one, at five values of Reynolds number. Information about temperature fields was obtained by statistically processing the array of sampled probe thermocouple indications at 300 points in the experimental channel cross section. Reach material has been obtained for verifying the codes used for calculating velocity and temperature fields in channels with

  6. Mutant swarms of a totivirus-like entities are present in the red macroalga Chondrus crispus and have been partially transferred to the nuclear genome.

    PubMed

    Rousvoal, Sylvie; Bouyer, Betty; López-Cristoffanini, Camilo; Boyen, Catherine; Collén, Jonas

    2016-08-01

    Chondrus crispus Stackhouse (Gigartinales) is a red seaweed found on North Atlantic rocky shores. Electrophoresis of RNA extracts showed a prominent band with a size of around 6,000 bp. Sequencing of the band revealed several sequences with similarity to totiviruses, double-stranded RNA viruses that normally infect fungi. This virus-like entity was named C. crispus virus (CcV). It should probably be regarded as an extreme viral quasispecies or a mutant swarm since low identity (<65%) was found between sequences. Totiviruses typically code for two genes: one capsid gene (gag) and one RNA-dependent RNA polymerase gene (pol) with a pseudoknot structure between the genes. Both the genes and the intergenic structures were found in the CcV sequences. A nonidentical gag gene was also found in the nuclear genome of C. crispus, with associated expressed sequence tags (EST) and upstream regulatory features. The gene was presumably horizontally transferred from the virus to the alga. Similar dsRNA bands were seen in extracts from different life cycle stages of C. crispus and from all geographic locations tested. In addition, similar bands were also observed in RNA extractions from other red algae; however, the significance of this apparently widespread phenomenon is unknown. Neither phenotype caused by the infection nor any virus particles or capsid proteins were identified; thus, the presence of viral particles has not been validated. These findings increase the known host range of totiviruses to include marine red algae. PMID:27151076

  7. Expression Profile of Genes as Indicators of Developmental Competence and Quality of In Vitro Fertilization and Somatic Cell Nuclear Transfer Bovine Embryos

    PubMed Central

    Monteleone, Melisa Carolina; Mucci, Nicolas; Kaiser, German Gustavo; Brocco, Marcela; Mutto, Adrián

    2014-01-01

    Reproductive biotechnologies such as in vitro fertilization (IVF) and somatic cell nuclear transfer (SCNT) enable improved reproductive efficiency of animals. However, the birth rate of in vitro-derived embryos still lags behind that of their in vivo counterparts. Thus, it is critical to develop an accurate evaluation and prediction system of embryo competence, both for commercial purposes and for scientific research. Previous works have demonstrated that in vitro culture systems induce alterations in the relative abundance (RA) of diverse transcripts and thus compromise embryo quality. The aim of this work was to analyze the RA of a set of genes involved in cellular stress (heat shock protein 70-kDa, HSP70), endoplasmic reticulum (ER) stress (immunoglobulin heavy chain binding protein, Bip; proteasome subunit β5, PSMB5) and apoptosis (BCL-2 associated X protein, Bax; cysteine aspartate protease-3, Caspase-3) in bovine blastocysts produced by IVF or SCNT and compare it with that of their in vivo counterparts. Poly (A) + mRNA was isolated from three pools of 10 blastocysts per treatment and analyzed by real-time RT-PCR. The RA of three of the stress indicators analyzed (Bax, PSMB5 and Bip) was significantly increased in SCNT embryos as compared with that of in vivo-derived blastocysts. No significant differences were found in the RA of HSP70 and Caspase-3 gene transcripts. This study could potentially complement morphological analyses in the development of an effective and accurate technique for the diagnosis of embryo quality, ultimately aiding to improve the efficiency of assisted reproductive techniques (ART). PMID:25269019

  8. Effects of the reproductive status on morphological oocyte quality and developmental competence of oocytes after in vitro fertilization and somatic cell nuclear transfer in cat.

    PubMed

    Naoi, H; Agung, B; Karja, N W K; Wongsrikeao, P; Shimizu, R; Taniguchi, M; Otoi, T

    2008-04-01

    This study was conducted to examine the effects of the reproductive cycle of donor cat on the quality of oocytes at recovery and developmental competence of oocytes after in vitro fertilization (IVF) and somatic cell nuclear transfer (NT). Based on the presence or absence of follicles and corpora lutea, the ovarian pairs collected were classified into inactive, follicular or luteal stages. After collection of oocytes, the oocytes were classified into four grades according to the morphological condition of oocyte cytoplasm and cumulus cells. A total of 16 558 oocytes were obtained from 198 ovarian pairs. The total mean numbers of oocytes and the mean numbers of oocytes with high quality (grade I) were significantly higher in ovarian pairs at the inactive stage (111.1 and 19.0 oocytes, respectively) than in ovarian pairs at the follicular stage (67.1 and 11.4 oocytes, respectively). A significant difference in the proportions of oocytes with grade I out of the total examined oocytes was observed between the follicular and luteal stages of ovaries (14.9% vs 20.2%, p < 0.05). The proportions of IVF embryos cleaved and developed to blastocysts significantly decreased with decreased quality of oocytes at recovery, irrespective of the reproductive status of ovaries. Moreover, there were no significant differences in the proportions of cleavage and development to the blastocyst stage of IVF and NT embryos among three oestrous stages of ovaries. These results indicate that the reproductive cycle stage of donor cat ovaries has no apparent effects on the in vitro development of oocytes after IVF and NT, but the quality of oocytes at recovery influences the development of IVF embryos. PMID:18325005

  9. Developmental Outcome and Related Abnormalities in Goats: Comparison Between Somatic Cell Nuclear Transfer- and In Vivo-Derived Concepti During Pregnancy Through Term.

    PubMed

    Martins, Leonardo Tondello; Neto, Saul Gaudêncio; Tavares, Kaio César Simiano; Calderón, Carlos Enrique Méndez; Aguiar, Luis Henrique; Lazzarotto, Cícera Regina; Ongaratto, Felipe Ledur; Rodrigues, Victor Hugo Vieira; Carneiro, Igor de Sá; Rossetto, Rafael; Almeida, Anderson Pinto; Fernandes, César Carneiro Linhares; Rondina, Davide; Dias, Ana Christina Oliveira; Chies, Jocelei Maria; Polejaeva, Irina A; Rodrigues, José Luiz; Forell, Fabiana; Bertolini, Luciana Relly; Bertolini, Marcelo

    2016-08-01

    Cloning by somatic cell nuclear transfer (SCNT) is characterized by low efficiency and the occurrence of developmental abnormalities, which are rather poorly studied phenomena in goats. This study aimed at comparing overall SCNT efficiency in goats by using in vitro-matured (IVM) or in vivo-matured oocytes and fibroblast donor cells (mock transfected, transgenic, or wild type), also characterizing symptoms of the Abnormal Offspring Syndrome (AOS) in development, comparing results with pregnancies produced by artificial insemination (AI) and in vivo-derived (IVD) embryos. The SCNT group had lower pregnancy rate (18.3%, 11/60), total number of concepti (20.0%, 12/60), term births (3.3%, 2/60), and live births (1.7%, 1/60) than both the IVD (77.8%, 7/9; 155.5%, 14/9; 122.2%, 11/9; 88.8%, 8/9) and the AI (71.4%, 10/14; 121.4%, 17/14; 100%, 14/14; 78.5%, 11/14) groups, respectively (p < 0.05). No SCNT pregnancies reached term using IVM oocytes, but in vivo-matured oocytes resulted in two term transgenic cloned kids. The proportion fetal membrane (FM) weight/birth weight reflected an increase in FM size and cotyledonary enlargement in clones, for disproportionally bigger newborns in relation to cotyledonary numbers. Overall, goat cloning showed losses and abnormality patterns similar to the AOS in cloned cattle and sheep, which have not been previously well recognized in goats. PMID:27362734

  10. Identification of Valid Housekeeping Genes for Real-Time Quantitative PCR Analysis of Collapsed Lung Tissues of Neonatal Somatic Cell Nuclear Transfer-Derived Cattle.

    PubMed

    Liu, Yan; Zhang, Yunhai; Jiang, Qiuling; Rao, Man; Sheng, Zheya; Zhang, Yu; Du, Weihua; Hao, Haisheng; Zhao, Xueming; Xu, Zhe; Liu, Jianning; Zhu, Huabin

    2015-10-01

    Cloned calves produced by somatic cell nuclear transfer frequently suffer alveolar collapse as newborns. To study the underlying pathophysiological mechanisms responsible for this phenomenon, the expression profiles of numerous genes involved in lung development need to be investigated. Quantitative real-time PCR is commonly adopted in gene expression analysis. However, selection of an appropriate reference gene for normalization is critical for obtaining reliable and accurate results. Seven housekeeping genes-β-glucuronidase (GUSB), phosphoglycerate kinase 1 (PGK1), β-2-microglobolin (B2M), peptidylprolyl isomerase A (PPIA), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), TATA-box binding protein (TBP), and 5.8S ribosomal RNA (5.8S rRNA)-were selected and evaluated as candidates. Their gene expression levels in the collapsed lungs of deceased neonate cloned calves and normal lung derived from normal calves were assessed. The ranking of gene expression stability was estimated by the geNorm, NormFinder, and BestKeeper programs. 5.8S rRNA and PPIA were determined to be the most stable reference genes by geNorm and BestKeeper, whereas the combination of GAPDH and TBP was suggested as reference genes by NormFinder. Taking these results into account, we conclude that 5.8S rRNA and PPIA could be the most reliable reference genes for studying the genes involved in alveolar collapse. Moreover, 5.8S rRNA could be represented as a uniform reference gene in similar cases. PMID:26393896

  11. Human metabolism and ecological transfer of radioactive caesium: Comparative studies of Chernobyl debris and nuclear weapons fallout, in Southern Sweden and in Bryansk, Russia

    NASA Astrophysics Data System (ADS)

    Raaf, Christopher Leopold

    The whole-body content of radiocaesium was measured in a South-Swedish urban group of people residing in the city of Lund (55.7°N, 13.2°E) between 1960 and 1994. The results from the survey have been analysed in order to estimate the ecological half-time, Teff,eco, of fallout radiocaesium and the aggregate transfer from ground deposition to man in the region. After 1987, the biological half-times, Ts, of 137Cs and 40K in man were also determined in the reference group through whole-body content measurements in combination with 24-hour urine sampling. Relationships between 24-hour urinary excretion and body burden of 137Cs in the group together with data from the literature were then applied to urine samples collected in 1994 and 1995 from adult subjects living in the highly contaminated region of Bryansk, Russia, in order to estimate their average body burden of 137Cs. The equivalent biological half-time for 137Cs in females of the Lund reference group was, on average (+/-1 WSE), 66 +/- 3 d, which agrees with other findings, whereas the value for the males, 81 +/- 4 d, was, on average, significantly lower than what is found in the literature. This is partly explained by the elevated mean age and relatively low mean body muscle mass of the males investigated in the group during the post-Chernobyl study period. The effective ecological half-time for 137Cs from Chernobyl was found to be 1.8 +/- 0.2 y. The aggregate transfer of 137Cs from deposition to mean activity concentration in man was estimated to be 1.7 Bq kg-1/kBq m-2. These vales may be compared with an effective ecological half-time of 1.3 years found in the reference group in the 1960s, and an aggregate transfer factor of 9.8 Bq kg-1/kBq m-2. The average committed effective dose from ingested 137Cs Chernobyl fallout in the study group was estimated to be 0.02 mSv and from the nuclear weapons fallout to 0.20 mSv. The estimates of whole-body content of 137Cs in the Russian subjects obtained through

  12. Fuel transfer system

    DOEpatents

    Townsend, Harold E.; Barbanti, Giancarlo

    1994-01-01

    A nuclear fuel bundle fuel transfer system includes a transfer pool containing water at a level above a reactor core. A fuel transfer machine therein includes a carriage disposed in the transfer pool and under the water for transporting fuel bundles. The carriage is selectively movable through the water in the transfer pool and individual fuel bundles are carried vertically in the carriage. In a preferred embodiment, a first movable bridge is disposed over an upper pool containing the reactor core, and a second movable bridge is disposed over a fuel storage pool, with the transfer pool being disposed therebetween. A fuel bundle may be moved by the first bridge from the reactor core and loaded into the carriage which transports the fuel bundle to the second bridge which picks up the fuel bundle and carries it to the fuel storage pool.

  13. Fuel transfer system

    DOEpatents

    Townsend, H.E.; Barbanti, G.

    1994-03-01

    A nuclear fuel bundle fuel transfer system includes a transfer pool containing water at a level above a reactor core. A fuel transfer machine therein includes a carriage disposed in the transfer pool and under the water for transporting fuel bundles. The carriage is selectively movable through the water in the transfer pool and individual fuel bundles are carried vertically in the carriage. In a preferred embodiment, a first movable bridge is disposed over an upper pool containing the reactor core, and a second movable bridge is disposed over a fuel storage pool, with the transfer pool being disposed therebetween. A fuel bundle may be moved by the first bridge from the reactor core and loaded into the carriage which transports the fuel bundle to the second bridge which picks up the fuel bundle and carries it to the fuel storage pool. 6 figures.

  14. Hemodynamic (fNIRS) and EEG (N200) correlates of emotional inter-species interactions modulated by visual and auditory stimulation

    PubMed Central

    Balconi, Michela; Vanutelli, Maria Elide

    2016-01-01

    The brain activity, considered in its hemodynamic (optical imaging: functional Near-Infrared Spectroscopy, fNIRS) and electrophysiological components (event-related potentials, ERPs, N200) was monitored when subjects observed (visual stimulation, V) or observed and heard (visual + auditory stimulation, VU) situations which represented inter-species (human-animal) interactions, with an emotional positive (cooperative) or negative (uncooperative) content. In addition, the cortical lateralization effect (more left or right dorsolateral prefrontal cortex, DLPFC) was explored. Both ERP and fNIRS showed significant effects due to emotional interactions which were discussed at light of cross-modal integration effects. The significance of inter-species effect for the emotional behavior was considered. In addition, hemodynamic and EEG consonant results and their value as integrated measures were discussed at light of valence effect. PMID:26976052

  15. Inter-species extrapolation of skin heating resulting from millimeter wave irradiation: modeling and experimental results.

    PubMed

    Nelson, D A; Walters, T J; Ryan, K L; Emerton, K B; Hurt, W D; Ziriax, J M; Johnson, L R; Mason, P A

    2003-05-01

    This study reports measurements of the skin surface temperature elevations during localized irradiation (94 GHz) of three species: rat (irradiated on lower abdomen), rhesus monkey (posterior forelimb), and human (posterior forearm). Two exposure conditions were examined: prolonged, low power density microwaves (LPM) and short-term, high power density microwaves (HPM). Temperature histories were compared with calculations from a bio-heat transfer model. The mean peak surface temperature increase was approximately 7.0 degrees C for the short-term HPM exposures for all three species/locations, and 8.5 degrees C (monkey, human) to 10.5 degrees C (rat) for the longer-duration LPM exposures. The HPM temperature histories are in close agreement with a one-dimensional conduction heat transfer model with negligible blood flow. The LPM temperature histories were compared with calculations from the bio-heat model, evaluated for various (constant) blood flow rates. Results suggest a variable blood flow model, reflecting a dynamic thermoregulatory response, may be more suited to describing skin surface temperature response under long-duration MMW irradiation. PMID:12747480

  16. Tracking interspecies transmission and long-term evolution of an ancient retrovirus using the genomes of modern mammals

    PubMed Central

    Diehl, William E; Patel, Nirali; Halm, Kate; Johnson, Welkin E

    2016-01-01

    Mammalian genomes typically contain hundreds of thousands of endogenous retroviruses (ERVs), derived from ancient retroviral infections. Using this molecular 'fossil' record, we reconstructed the natural history of a specific retrovirus lineage (ERV-Fc) that disseminated widely between ~33 and ~15 million years ago, corresponding to the Oligocene and early Miocene epochs. Intercontinental viral spread, numerous instances of interspecies transmission and emergence in hosts representing at least 11 mammalian orders, and a significant role for recombination in diversification of this viral lineage were also revealed. By reconstructing the canonical retroviral genes, we identified patterns of adaptation consistent with selection to maintain essential viral protein functions. Our results demonstrate the unique potential of the ERV fossil record for studying the processes of viral spread and emergence as they play out across macro-evolutionary timescales, such that looking back in time may prove insightful for predicting the long-term consequences of newly emerging viral infections. DOI: http://dx.doi.org/10.7554/eLife.12704.001 PMID:26952212

  17. Daphnia and fish toxicity of (benzo)triazoles: validated QSAR models, and interspecies quantitative activity-activity modelling.

    PubMed

    Cassani, Stefano; Kovarich, Simona; Papa, Ester; Roy, Partha Pratim; van der Wal, Leon; Gramatica, Paola

    2013-08-15

    Due to their chemical properties synthetic triazoles and benzo-triazoles ((B)TAZs) are mainly distributed to the water compartments in the environment, and because of their wide use the potential effects on aquatic organisms are cause of concern. Non testing approaches like those based on quantitative structure-activity relationships (QSARs) are valuable tools to maximize the information contained in existing experimental data and predict missing information while minimizing animal testing. In the present study, externally validated QSAR models for the prediction of acute (B)TAZs toxicity in Daphnia magna and Oncorhynchus mykiss have been developed according to the principles for the validation of QSARs and their acceptability for regulatory purposes, proposed by the Organization for Economic Co-operation and Development (OECD). These models are based on theoretical molecular descriptors, and are statistically robust, externally predictive and characterized by a verifiable structural applicability domain. They have been applied to predict acute toxicity for over 300 (B)TAZs without experimental data, many of which are in the pre-registration list of the REACH regulation. Additionally, a model based on quantitative activity-activity relationships (QAAR) has been developed, which allows for interspecies extrapolation from daphnids to fish. The importance of QSAR/QAAR, especially when dealing with specific chemical classes like (B)TAZs, for screening and prioritization of pollutants under REACH, has been highlighted. PMID:23702385

  18. Interspecies comparison of stellate cell-containing macula flavae and vitamin A storage in vocal fold mucosa

    PubMed Central

    Toya, Yutaka; Riabroy, Napaporn; Davis, Christopher R; Kishimoto, Yo; Tanumihardjo, Sherry A; Bless, Diane M; Welham, Nathan V

    2014-01-01

    The macula flavae (MF), populated by vitamin A-storing stellate cells (SCs), are believed to play a fundamental role in development, maintenance and repair of the vocal fold (VF) mucosa; however, to date, they have mostly been examined in observational human cadaver studies. Here, we conducted an interspecies comparison of MF and SC phenotype, as well as vitamin A quantification and localization, in human, pig, dog, rabbit and rat VF mucosae. MF containing vitamin A-positive SCs were only identified in human and rat specimens. Pig, dog and rabbit VF mucosae contained no discernable MF, but rather exhibited preferential vitamin A localization to mucous (pig), serous (dog) or mixed (rabbit) glands. This glandular vitamin A storage corresponded to exceedingly high concentrations of retinol in pig and dog mucosae, and retinyl ester in dog mucosa. These findings have significant implications for the presumed role of the MF and SCs in VF biology, the nature of vitamin A storage within the VF mucosa, and the selection of an appropriate animal model for future experimental studies. PMID:25040030

  19. Impact of Gestational Bisphenol A on Oxidative Stress and Free Fatty Acids: Human Association and Interspecies Animal Testing Studies

    PubMed Central

    Veiga-Lopez, Almudena; Pennathur, Subramaniam; Kannan, Kurunthachalam; Patisaul, Heather B.; Dolinoy, Dana C.; Zeng, Lixia

    2015-01-01

    Bisphenol A (BPA) is a high production volume chemical and an endocrine disruptor. Developmental exposures to BPA have been linked to adult metabolic pathologies, but the pathways through which these disruptions occur remain unknown. This is a comprehensive interspecies association vs causal study to evaluate risks posed by prenatal BPA exposure and to facilitate discovery of biomarkers of relevance to BPA toxicity. Samples from human pregnancies during the first trimester and at term, as well as fetal and/or adult samples from prenatally BPA-treated sheep, rats, and mice, were collected to assess the impact of BPA on free fatty acid and oxidative stress dynamics. Mothers exposed to higher BPA during early to midpregnancy and their matching term cord samples displayed increased 3-nitrotyrosine (NY), a marker of nitrosative stress. Maternal samples had increased palmitic acid, which was positively correlated with NY. Sheep fetuses and adult sheep and rats prenatally exposed to a human-relevant exposure dose of BPA showed increased systemic nitrosative stress. The strongest effect of BPA on circulating free fatty acids was observed in adult mice in the absence of increased oxidative stress. This is the first multispecies study that combines human association and animal causal studies assessing the risk posed by prenatal BPA exposure to metabolic health. This study provides evidence of the induction of nitrosative stress by prenatal BPA in both the mother and fetus at time of birth and is thus supportive of the use of maternal NY as a biomarker for offspring health. PMID:25603046

  20. Clonal spread and interspecies transmission of clinically relevant ESBL-producing Escherichia coli of ST410--another successful pandemic clone?

    PubMed

    Schaufler, Katharina; Semmler, Torsten; Wieler, Lothar H; Wöhrmann, Michael; Baddam, Ramani; Ahmed, Niyaz; Müller, Kerstin; Kola, Axel; Fruth, Angelika; Ewers, Christa; Guenther, Sebastian

    2016-01-01

    Clinically relevant extended-spectrum beta-lactamase (ESBL)-producing multi-resistant Escherichia coli have been on the rise for years. Initially restricted to mostly a clinical context, recent findings prove their prevalence in extraclinical settings independent of the original occurrence of antimicrobial resistance in the environment. To get further insights into the complex ecology of potentially clinically relevant ESBL-producing E. coli, 24 isolates from wild birds in Berlin, Germany, and 40 ESBL-producing human clinical E. coli isolates were comparatively analyzed. Isolates of ST410 occurred in both sample groups (six). In addition, three ESBL-producing E. coli isolates of ST410 from environmental dog feces and one clinical dog isolate were included. All 10 isolates were clonally analyzed showing almost identical macrorestriction patterns. They were chosen for whole-genome sequencing revealing that the whole-genome content of these 10 E. coli isolates showed a very high genetic similarity, differing by low numbers of single nucleotide polymorphisms only. This study gives initial evidence for a recent interspecies transmission of a new successful clone of ST410 E. coli between wildlife, humans, companion animals and the environment. The results underline the zoonotic potential of clinically relevant multi-resistant bacteria found in the environment as well as the mandatory nature of the 'One Health' approach. PMID:26656065

  1. Impact of gestational bisphenol A on oxidative stress and free fatty acids: Human association and interspecies animal testing studies.

    PubMed

    Veiga-Lopez, Almudena; Pennathur, Subramaniam; Kannan, Kurunthachalam; Patisaul, Heather B; Dolinoy, Dana C; Zeng, Lixia; Padmanabhan, Vasantha

    2015-03-01

    Bisphenol A (BPA) is a high production volume chemical and an endocrine disruptor. Developmental exposures to BPA have been linked to adult metabolic pathologies, but the pathways through which these disruptions occur remain unknown. This is a comprehensive interspecies association vs causal study to evaluate risks posed by prenatal BPA exposure and to facilitate discovery of biomarkers of relevance to BPA toxicity. Samples from human pregnancies during the first trimester and at term, as well as fetal and/or adult samples from prenatally BPA-treated sheep, rats, and mice, were collected to assess the impact of BPA on free fatty acid and oxidative stress dynamics. Mothers exposed to higher BPA during early to midpregnancy and their matching term cord samples displayed increased 3-nitrotyrosine (NY), a marker of nitrosative stress. Maternal samples had increased palmitic acid, which was positively correlated with NY. Sheep fetuses and adult sheep and rats prenatally exposed to a human-relevant exposure dose of BPA showed increased systemic nitrosative stress. The strongest effect of BPA on circulating free fatty acids was observed in adult mice in the absence of increased oxidative stress. This is the first multispecies study that combines human association and animal causal studies assessing the risk posed by prenatal BPA exposure to metabolic health. This study provides evidence of the induction of nitrosative stress by prenatal BPA in both the mother and fetus at time of birth and is thus supportive of the use of maternal NY as a biomarker for offspring health. PMID:25603046

  2. The olive knot disease as a model to study the role of interspecies bacterial communities in plant disease

    PubMed Central

    Buonaurio, Roberto; Moretti, Chiaraluce; da Silva, Daniel Passos; Cortese, Chiara; Ramos, Cayo; Venturi, Vittorio

    2015-01-01

    There is an increasing interest in studying interspecies bacterial interactions in diseases of animals and plants as it is believed that the great majority of bacteria found in nature live in complex communities. Plant pathologists have thus far mainly focused on studies involving single species or on their interactions with antagonistic competitors. A bacterial disease used as model to study multispecies interactions is the olive knot disease, caused by Pseudomonas savastanoi pv. savastanoi (Psv). Knots caused by Psv in branches and other aerial parts of the olive trees are an ideal niche not only for the pathogen but also for many other plant-associated bacterial species, mainly belonging to the genera Pantoea, Pectobacterium, Erwinia, and Curtobacterium. The non-pathogenic bacterial species Erwinia toletana, Pantoea agglomerans, and Erwinia oleae, which are frequently isolated inside the olive knots, cooperate with Psv in modulating the disease severity. Co-inoculations of these species with Psv result in bigger knots and better bacterial colonization when compared to single inoculations. Moreover, harmless bacteria co-localize with the pathogen inside the knots, indicating the formation of stable bacterial consortia that may facilitate the exchange of quorum sensing signals and metabolites. Here we discuss the possible role of bacterial communities in the establishment and development of olive knot disease, which we believe could be taking place in many other bacterial plant diseases. PMID:26113855

  3. The olive knot disease as a model to study the role of interspecies bacterial communities in plant disease.

    PubMed

    Buonaurio, Roberto; Moretti, Chiaraluce; da Silva, Daniel Passos; Cortese, Chiara; Ramos, Cayo; Venturi, Vittorio

    2015-01-01

    There is an increasing interest in studying interspecies bacterial interactions in diseases of animals and plants as it is believed that the great majority of bacteria found in nature live in complex communities. Plant pathologists have thus far mainly focused on studies involving single species or on their interactions with antagonistic competitors. A bacterial disease used as model to study multispecies interactions is the olive knot disease, caused by Pseudomonas savastanoi pv. savastanoi (Psv). Knots caused by Psv in branches and other aerial parts of the olive trees are an ideal niche not only for the pathogen but also for many other plant-associated bacterial species, mainly belonging to the genera Pantoea, Pectobacterium, Erwinia, and Curtobacterium. The non-pathogenic bacterial species Erwinia toletana, Pantoea agglomerans, and Erwinia oleae, which are frequently isolated inside the olive knots, cooperate with Psv in modulating the disease severity. Co-inoculations of these species with Psv result in bigger knots and better bacterial colonization when compared to single inoculations. Moreover, harmless bacteria co-localize with the pathogen inside the knots, indicating the formation of stable bacterial consortia that may facilitate the exchange of quorum sensing signals and metabolites. Here we discuss the possible role of bacterial communities in the establishment and development of olive knot disease, which we believe could be taking place in many other bacterial plant diseases. PMID:26113855

  4. Inhalation reference dose (RfDi): An application of interspecies dosimetry modeling for risk assessment of insoluble particles

    SciTech Connect

    Jarabek, A.M.; Menache, M.G.; Overton, H.; Dourson, M.L.; Miller, F.J.

    1989-01-01

    Accurate extrapolation of animal toxicity data for human health risk assessment requires determination of the effective dose to the target tissue and the sensitivity of the target tissue to that dose. The methodology for deriving reference doses (the U.S. Environmental Protection Agency's (EPA) benchmark values for gauging systemic toxicity) for oral exposures has not included dosimetry modeling. Dosimetry data facilitate evaluation of concentration-response data with respect to the dose-response relationships used in quantitative risk assessment. Extension of the methodology to derivation of inhalation reference doses (RfDi) should account for the dynamics of the respiratory system as the portal of entry. The paper presents a method for calculating a dosimetric adjustment factor based on the values for the initial deposited dose of insoluble particles in an animal species and in humans. The application for insoluble particles illustrates the feasibility of interspecies dosimetry calculations for extrapolating the toxicological results of inhaled agents to human exposure conditions for more accurate risk estimation.

  5. Inhalation reference dose (RfDi): an application of interspecies dosimetry modeling for risk assessment of insoluble particles.

    PubMed

    Jarabek, A M; Menache, M G; Overton, J H; Dourson, M L; Miller, F J

    1989-01-01

    Accurate extrapolation of animal toxicity data for human health risk assessment requires determination of the effective dose to the target tissue and the sensitivity of the target tissue to that dose. The methodology for deriving reference doses [the U.S. Environmental Protection Agency's (EPA) benchmark values for gauging systemic toxicity] for oral exposures has not included dosimetry modeling. Dosimetry data facilitate evaluation of concentration-response data with respect to the dose-response relationships used in quantitative risk assessment. Extension of this methodology to derivation of inhalation reference doses (RfDi) should account for the dynamics of the respiratory system as the portal of entry. Predictive physiologically based modeling of the inhalation of reactive gases has recently been demonstrated (Overton and Miller 1988). Models that describe the deposition of hygroscopic particles and account for chemical factors that affect clearance mechanisms and gas uptake are under development. This paper presents a method for calculating a dosimetric adjustment factor based on the values for the initial deposited dose of insoluble particles in an animal species and in humans. The ratio of these two values serves as a scaling factor that can be applied in the R f D methodology to account for the dosimetric differences in the inhaled deposited dose. This application for insoluble particles illustrates the feasibility of interspecies dosimetry calculations for extrapolating the toxicological results of inhaled agents to human exposure conditions for more accurate risk estimation. PMID:2606680

  6. Inhalation reference dose (RfDi): An application of interspecies dosimetry modeling for risk assessment of insoluble particles

    SciTech Connect

    Jarabek, A.M.; Menache, M.G.; Overton, J.H. Jr.; Dourson, M.L.; Miller, F.J. )

    1989-01-01

    Accurate extrapolation of animal toxicity data for human health risk assessment requires determination of the effective dose to the target tissue and the sensitivity of the target tissue to that dose. The methodology for deriving reference doses (the U.S. Environmental Protection Agency's (EPA) benchmark values for gauging systemic toxicity) for oral exposures has not included dosimetry modeling. Dosimetry data facilitate evaluation of concentration-response data with respect to the dose-response relationships used in quantitative risk assessment. Extension of this methodology to derivation of inhalation reference doses (RfDi) should account for the dynamics of the respiratory system as the portal of entry. Predictive physiologically based modeling of the inhalation of reactive gases has recently been demonstrated. Models that describe the deposition of hygroscopic particles and account for chemical factors that affect clearance mechanisms and gas uptake are under development. This paper presents a method for calculating a dosimetric adjustment factor based on the values for the initial deposited dose of insoluble particles in an animal species and in humans. The ratio of these two values serves as a scaling factor that can be applied in the R f D methodology to account for the dosimetric differences in the inhaled deposited dose. This application for insoluble particles illustrates the feasibility of interspecies dosimetry calculations for extrapolating the toxicological results of inhaled agents to human exposure conditions for more accurate risk estimation.

  7. Tumorigenesis of nuclear transfer-derived embryonic stem cells is reduced through differentiation and enrichment following transplantation in the infarcted rat heart.

    PubMed

    Fu, Qiang; Su, Dechun; Wang, Ke; Zhao, Yingjun

    2016-06-01

    The aim of the present study was to evaluate the tumorigenic potential of nuclear transfer-derived (nt) mouse embryonic stem cells (mESCs) transplanted into infarcted rat hearts. The nt‑mESCs were cultured using a bioreactor system to develop embryoid bodies, which were induced with 1% ascorbic acid to differentiate into cardiomyocytes. The nt‑mESC‑derived cardiomyocytes (nt‑mESCs‑CMs) were enriched using Percoll density gradient separation to generate nt‑mESCs‑percoll‑enriched (PE)‑CMs. Ischemia was induced by ligating the left anterior descending coronary artery in female Sprague‑Dawley rats. Immunosuppressed rats (daily intraperitoneal injections of cyclosporine A and methylprednisolone) were randomly assigned to receive an injection containing 5x106 mESCs, nt‑mESCs, nt‑mESC‑CMs or nt‑mESC‑PE‑CMs. Analysis performed 8 weeks following transplantation revealed teratoma formation in 80, 86.67 and 33.33% of the rats administered with the mESCs, nt‑mESCs and nt‑mESC‑CMs, respectively, indicating no significant difference between the mESCs and nt‑mESCs; but significance (P<0.05) between the nt‑mESC‑CMs and nt‑mESCs. The mean tumor volumes were 82.72±6.52, 83.17±3.58 and 50.40±5.98 mm3, respectively (P>0.05 mESCs, vs. nt‑mESCs; P<0.05 nt‑mESC‑CMs, vs. nt‑mESCs). By contrast, no teratoma formation was detected in the rats, which received nt‑mESC‑PE‑CMs. Octamer‑binding transcription factor‑4, a specific marker of undifferentiated mESCs, was detected using polymerase chain reaction in the rats, which received nt‑mESCs and nt‑mESC‑CMs, but not in rats administered with nt‑mESC‑PE‑CMs. In conclusion, nt‑mESCs exhibited the same pluripotency as mESCs, and teratoma formation following nt‑mESC transplantation was reduced by cell differentiation and enrichment. PMID:27082733

  8. Interspecies comparison of the metabolism and dosimetry of inhaled mixed oxides of plutonium and uranium

    SciTech Connect

    Boecker, B.B.; Mewhinney, J.A.; Eidson, A.F.

    1997-12-01

    Three studies were conducted to provide information on the biological fate, distribution of radiation doses among tissues, and implications for potential health consequences of an inhalation exposure to mixed-oxide nuclear fuel materials. In each study, Fischer-344 rats, beagle dogs, and cynomolgus monkeys inhaled one of three aerosols: 750{degrees}C calcined mixed oxides of UO{sub 2} and PuO{sub 2}, 1750{degrees}C sintered (U,Pu)O{sub 2}, or 850{degrees}C calcined {open_quotes}pure{close_quotes} PuO{sub 2}. These materials were collected from glove-box enclosures immediately after industrial processing of mixed-oxide fuel materials. Lung retention, tissue distribution, and mode of excretion of {sup 238-240}Pu, {sup 241}Am, and uranium (when present) were quantified by radiochemical analysis of tissue and excreta samples from animals sacrificed at selected times to 6.5 yr after inhalation exposure.

  9. Production of cloned NIBS (Nippon Institute for Biological Science) and α-1, 3-galactosyltransferase knockout MGH miniature pigs by somatic cell nuclear transfer using the NIBS breed as surrogates

    PubMed Central

    Shimatsu, Yoshiki; Yamada, Kazuhiko; Horii, Wataru; Hirakata, Atsushi; Sakamoto, Yuji; Waki, Shiori; Sano, Junichi; Saitoh, Toshiki; Sahara, Hisashi; Shimizu, Akira; Yazawa, Hajime; Sachs, David H.; Nunoya, Tetsuo

    2013-01-01

    Background Nuclear transfer (NT) technologies offer a means for producing the genetically modified pigs necessary to develop swine models for mechanistic studies of disease processes as well as to serve as organ donors for xenotransplantation. Most previous studies have used commercial pigs as surrogates. Method and Results In this study, we established a cloning technique for miniature pigs by somatic cell nuclear transfer (SCNT) using Nippon Institute for Biological Science (NIBS) miniature pigs as surrogates. Moreover, utilizing this technique, we have successfully produced an α-1, 3-galactosyltransferase knockout (GalT-KO) miniature swine. Fibroblasts procured from a NIBS miniature pig fetus were injected into 1312 enucleated oocytes. The cloned embryos were transferred to 11 surrogates of which five successfully delivered 13 cloned offspring; the production efficiency was 1.0% (13/1312). In a second experiment, lung fibroblasts obtained from neonatal GalT-KO MGH miniature swine were used as donor cells and 1953 cloned embryos were transferred to 12 surrogates. Six cloned offspring were born from five surrogates, a production efficiency of 0.3% (6/1953). Conclusions These results demonstrate successful establishment of a miniature pig cloning technique by SCNT using NIBS miniature pigs as surrogates. To our knowledge, this is the first demonstration of successful production of GalT-KO miniature swine using miniature swine surrogates. This technique could help to ensure a stable supply of the cloned pigs through the use of miniature pig surrogates and could expand production in countries with limited space or in facilities with special regulations such as specific pathogen-free or good laboratory practice. PMID:23581451

  10. Lowering storage temperature during ovary transport is beneficial to the developmental competence of bovine oocytes used for somatic cell nuclear transfer.

    PubMed

    Wang, Y S; Zhao, X; Su, J M; An, Z X; Xiong, X R; Wang, L J; Liu, J; Quan, F S; Hua, S; Zhang, Y

    2011-03-01

    The objective of this study was to determine the effect of storage temperature during ovary transport on the developmental competence of bovine oocytes for use in somatic cell nuclear transfer (SCNT). Ovaries obtained from a slaughterhouse were stored in physiological saline for 3-4h at one of the three temperatures: 15 °C, 25 °C, or 35 °C. The developmental competence of oocytes used for SCNT was ascertained by cleavage and blastocyst formation rate, total cell number, apoptosis index, and the relative abundance of Bax and Hsp70.1 in day 7 blastocysts. Ovaries stored at 35 °C for 3-4h reduced the recovery rate of grade I and II oocytes compared with those stored at 25 °C or 15 °C (45.1±0.7% vs. 76.7±1.2% or 74.8±2.0%, P<0.05). The proportion of oocytes matured to the MII stage (maturation rate) for oocytes stored at 35 °C was significantly lower than those stored at 25 °C or 15 °C (51.3±0.9% vs. 75.1±1.4% or 71.7±1.3%, P<0.05). Cleavage rate (77.7±2.1%, 77.9±1.1% and 72.1±0.7% for 15 °C, 25 °C and 35 °C groups, respectively) and blastocyst formation rate (39.1±0.5%, 36.8±1.4% and 32.2±0.9% for 15 °C, 25 °C and 35 °C groups, respectively) following SCNT were not significantly different between treatments. Oocytes from ovaries stored at 15 °C, however, produced blastocysts with higher cell numbers (97.3±8.6 vs. 80.2±10.8 or 77.4±11.7; P<0.05) and lower apoptotic index (5.1±1.3 vs. 13.5±1.6 or 18.6±1.1, P<0.05) than those stored at 25 °C or 35 °C. The relative abundance of Bax and Hsp70.1 in day 7 blastocysts produced from oocytes derived from ovaries stored at 15 °C was lower than those stored at 25 °C or 35 °C (P<0.05). It was concluded that a storage temperature of 15 °C for a 3-4h period had a significant beneficial effect on the quality and developmental competence of oocytes used for SCNT due to the alleviation of stresses on the oocytes compared with those subjected to storage temperatures of 25 °C or 35 °C. PMID

  11. Estimated emissions of chlorofluorocarbons, hydrochlorofluorocarbons, and hydrofluorocarbons based on an interspecies correlation method in the Pearl River Delta region, China.

    PubMed

    Wu, Jing; Fang, Xuekun; Martin, Jonathan W; Zhai, Zihan; Su, Shenshen; Hu, Xia; Han, Jiarui; Lu, Sihua; Wang, Chen; Zhang, Jianbo; Hu, Jianxin

    2014-02-01

    Although many studies have been conducted in recent years on the emissions of chlorofluorocarbons (CFCs), hydrochlorofluorocarbons (HCFCs), and hydrofluorocarbons (HFCs) at the large regional (such as East Asia) and national scales, relatively few studies have been conducted for cities or metropolitan areas. In this study, 192 air samples were collected in the Pearl River Delta (PRD) region of China in November 2010. The atmospheric mixing ratios of six halocarbons were analyzed, including trichlorofluoromethane (CFC-11, CCl3F), dichlorodifluoromethane (CFC-12, CCl2F2), monochlorodifluoromethane (HCFC-22, CHClF2), 1,1-dichloro-1-fluoroethane (HCFC-141b, CH3CCl2F), 1-dichloro-1,1-fluoroethane (HCFC-142b, CH3CClF2), and 1,1,1,2-tetrafluoroethane (HFC-134a, CH2FCF3), and their emissions were estimated based on an interspecies correlation method using HCFC-22 as the reference species. The results showed no significant change in the regional concentration and emission of CFC in the past 10years, suggesting that the continuous regional emission of CFC has had no significant effect on the CFC regional concentration in the PRD region. Concentrations and emissions of HCFCs and HFCs are significantly higher compared to previous research in the PRD region (P<0.05). The largest emission was for HCFC-22, most likely due to its substitution for CFC-12 in the industrial and commercial refrigeration subsector, and the rapid development of the room air-conditioner and extruded polystyrene subsectors. The PRD's ODP-weighted emissions of the target HCFCs provided 9% (7-12%) of the national emissions for the corresponding species. The PRD's GWP-weighted emissions of the target HCFCs and HFC-134a account for 10% (7-12%) and 8% (7-9%), respectively, of the national emissions for the corresponding species, and thus are important contributions to China's total emissions. PMID:24189105

  12. Derivation of freshwater quality criteria for zinc using interspecies correlation estimation models to protect aquatic life in China.

    PubMed

    Feng, C L; Wu, F C; Dyer, S D; Chang, H; Zhao, X L

    2013-01-01

    Species sensitivity distributions (SSDs) are usually used in the development of water quality criteria and require a large number of toxicity values to define a hazard level to protect the majority of species. However, some toxicity data for certain chemicals are limited, especially for endangered and threatened species. Thus, it is important to predict the unknown species toxicity data using available toxicity data. To address this need, interspecies correlation estimation (ICE) models were developed by US EPA to predict acute toxicity of chemicals to diverse species based on a more limited data set of surrogate species toxicity data. Use of SSDs generated from ICE models allows for the prediction of protective water quality criteria, such as the HC5 (hazard concentration, 5th percentile). In the present study, we tested this concept using toxicity data collected for zinc. ICE-based-SSDs were generated using three surrogate species (common carp (Cyprinus carpio), rainbow trout (Oncorhynchus mykiss), and Daphnia magna) and compared with the measured-based SSD and corresponding HC5. The results showed that no significant differences were observed between the ICE- and the measured-based SSDs and HC5s. Furthermore, the examination of species placements within the SSDs indicated that the most sensitive species to zinc were invertebrates, especially crustaceans. Given the similarity of SSD and HC5s for zinc, the use of ICE to derive potential water quality criteria for diverse chemicals in China is proposed. Further, a combination of measured and ICE-derived data will prove useful for assessing water quality and chemical risks in the near future. PMID:23058200

  13. Genetic Adaptation of Influenza A Viruses in Domestic Animals and Their Potential Role in Interspecies Transmission: A Literature Review.

    PubMed

    Munoz, Olga; De Nardi, Marco; van der Meulen, Karen; van Reeth, Kristien; Koopmans, Marion; Harris, Kate; von Dobschuetz, Sophie; Freidl, Gudrun; Meijer, Adam; Breed, Andrew; Hill, Andrew; Ko