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Sample records for irradiated mouse chimeras

  1. Inherited effects from irradiated mouse immature oocytes detected in aggregation embryo chimeras

    International Nuclear Information System (INIS)

    Straume, T.; Raabe, O.G.; Walsh, K.J.; Wiley, L.M.

    1993-01-01

    Data obtained using the mouse-preimplantation-embryo-chimera assay are presented that show a transmitted effect following low-dose irradiation of immature oocytes in vivo. Six-week-old female mice were irradiated using 137 Cs-γ-rays (0.05 Gy, 0.15 Gy, and unexposed controls). At 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 and 12 weeks post exposure, the mice were mated and aggregation chimeras made from the 4-cell embryos. Three independent experiments have now been carried out, all showing a significant embryonic cell-proliferation disadvantage of the embryos obtained from the females treated 7 weeks previously, i.e., embryos from oocytes that were immature at the time of radiation exposure. No effect was detected at 1-6 weeks when embryos were obtained from maturing oocytes. Also, the effect was not seen at 8, 9, 10, 11, and 12 weeks post exposure. The implications of these results are discussed in the light of previous studies on mouse oocytes

  2. Assay using embryo aggregation chimeras for the detection of nonlethal changes in X-irradiated mouse preimplantation embryos

    International Nuclear Information System (INIS)

    Obasaju, M.F.; Wiley, L.M.; Oudiz, D.J.; Miller, L.; Samuels, S.J.; Chang, R.J.; Overstreet, J.W.

    1988-01-01

    We have developed a short-term in vitro assay for the detection of sublethal effects produced by very low levels of ionizing radiation. The assay utilizes mouse embryo aggregation chimeras consisting of one irradiated embryo paired with an unirradiated embryo whose blastomeres have been labeled with fluorescein isothiocyanate (FITC). X irradiation (from 0.05 to 2 Gy) and chimera construction were performed with four-cell stage embryos, and the chimeras were cultured for 40 h to the morula stage. The morulae were partially dissociated with calcium-free culture medium and viewed under phase contrast and epifluorescence microscopy to obtain total embryo cell number and the cellular contribution of irradiated (unlabeled) and control (FITC labeled) embryos per chimera. In chimeras where neither embryo was irradiated, the ratio of the unlabeled blastomeres to the total number of blastomeres per chimera embryo was 0.50 (17.8 +/- 5.6 cells per unlabeled embryo and 17.4 +/- 5.5 cells per FITC-labeled partner embryo). However, in chimeras formed after the unlabeled embryos were irradiated with as little as 0.05 Gy, the ratio of unlabeled blastomeres to the total number of blastomeres per chimera embryo was 0.43 (P less than 0.01). The apparent decreases in cell proliferation were not observed in irradiated embryos that were merely cocultured with control embryos, regardless of whether the embryos were zona enclosed or zona free. We conclude that very low levels of radiation induce sublethal changes in cleaving embryos that are expressed as a proliferative disadvantage within two cell cycles when irradiated embryos are in direct cell-to-cell contact with unirradiated embryos

  3. Mouse immature oocytes irradiated in vivo at 14-days of age and evaluated for transmitted effects using the aggregation embryo chimera assay

    International Nuclear Information System (INIS)

    Straume, T.; Raabe, O.G.; Walsh, K.J.; Wiley, L.M.

    1996-01-01

    A previous study using the mouse-preimplantation-embryo-chimera assay demonstrated a reproducible transmitted effect (proliferation disadvantage observed in early embryos) from females irradiated as 49-day-old adults using 0.15 Gy of gamma rays and then mated seven weeks later, i.e., embryos were from oocytes that were immature at time of irradiation. Because mouse immature oocytes are known to be much more radiosensitive to cell killing in juveniles than in adults, a follow-on study was performed here using 14-day-old juvenile mice. In contrast to adults, the exposure of juveniles to 0.15 Gy of gamma rays did not result in a detectable transmitted proliferation disadvantage when animals were mated 7 or 12 weeks later. This observation is discussed in light of previous studies on mouse immature oocytes and embryo chimeras

  4. Histogenesis of mouse sarcomas induced by implantation of polyvinyl chloride film in radiation chimeras

    International Nuclear Information System (INIS)

    Mojzhess, T.G.; Prigozhina, E.L.

    1976-01-01

    Sarcomas were induced in CBA/CBA-T6T6 mouse radiation chimeras by implantation of polyvinyl chloride film subcutaneously 13 months after irradiation and injection of donor's bone marrow. Of the 12 tumors studied 11 had the recipient's karyotype and one the donor's. The formation of connective-tissue cells from bone-marrow precursors thus, evidently does not play an essential role in the histogenesis of sarcomas induced by plastics

  5. MODELS FOR MOUSE CHIMERA PRODUCTION: AGGREGATION OF ES CELLS WITH CLEAVAGE STAGE EMBRYOS

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    STANCA CLAUDIA

    2007-01-01

    Full Text Available In a mutant ES cells↔ wild-type embryo chimera, ES cells behave more like epiblastcells. They can contribute to the primitive ectoderm layers, which give rise to all theembryonic tissues and some extraembryonic tissues (Beddington and Robertson,1989, but not to trophectoderm or primitive endoderm. Using transgenic ES celllines, aggregated with cleavage stage host embryo, ES cells can integrate randomlyin the embryo proper. If they will be take part in the formation of ICM (inner cellmass, it will be possible to obtain germline chimera animals. To generate ES cells↔ cleavage stage host embryo chimeras, we used (CD-1 mice as donors of hostembryos as well as recipients of manipulated embryos. For chimera production, weused fluorescent-labeled ES cell line (CD1/EGFP, because in this case we canfollow the fate of ES cells during the embryonic development. We produced thechimers using “aggregation chimera technique”. 8 cells stage zona pellucida free,mouse embryos were aggregated in an aggregation plates, with a clump of ES cells(10 – 15 cells. The chimera embryos were cultivated for 24 hours in the incubator(at 37 °C, 5% CO2 in air. The chimera blastocysts resulted after cultivation, weretransferred to the uterus of the 2.5-dpc pseudo pregnant females.

  6. MODELS FOR MOUSE CHIMERA PRODUCTION: AGGREGATION OF ES CELLS WITH CLEAVAGE STAGE EMBRYOS

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    CLAUDIA STANCA

    2007-05-01

    Full Text Available In a mutant ES cells↔ wild-type embryo chimera, ES cells behave more like epiblastcells. They can contribute to the primitive ectoderm layers, which give rise to all theembryonic tissues and some extraembryonic tissues (Beddington and Robertson,1989, but not to trophectoderm or primitive endoderm. Using transgenic ES celllines, aggregated with cleavage stage host embryo, ES cells can integrate randomlyin the embryo proper. If they will be take part in the formation of ICM (inner cellmass, it will be possible to obtain germline chimera animals. To generate ES cells↔ cleavage stage host embryo chimeras, we used (CD-1 mice as donors of hostembryos as well as recipients of manipulated embryos. For chimera production, weused fluorescent-labeled ES cell line (CD1/EGFP, because in this case we canfollow the fate of ES cells during the embryonic development. We produced thechimers using “aggregation chimera technique”. 8 cells stage zona pellucida free,mouse embryos were aggregated in an aggregation plates, with a clump of ES cells(10 – 15 cells. The chimera embryos were cultivated for 24 hours in the incubator(at 37 °C, 5% CO2 in air. The chimera blastocysts resulted after cultivation, weretransferred to the uterus of the 2.5-dpc pseudo pregnant females.

  7. Inhibition of Apoptosis Overcomes Stage-Related Compatibility Barriers to Chimera Formation in Mouse Embryos.

    Science.gov (United States)

    Masaki, Hideki; Kato-Itoh, Megumi; Takahashi, Yusuke; Umino, Ayumi; Sato, Hideyuki; Ito, Keiichi; Yanagida, Ayaka; Nishimura, Toshinobu; Yamaguchi, Tomoyuki; Hirabayashi, Masumi; Era, Takumi; Loh, Kyle M; Wu, Sean M; Weissman, Irving L; Nakauchi, Hiromitsu

    2016-11-03

    Cell types more advanced in development than embryonic stem cells, such as EpiSCs, fail to contribute to chimeras when injected into pre-implantation-stage blastocysts, apparently because the injected cells undergo apoptosis. Here we show that transient promotion of cell survival through expression of the anti-apoptotic gene BCL2 enables EpiSCs and Sox17 + endoderm progenitors to integrate into blastocysts and contribute to chimeric embryos. Upon injection into blastocyst, BCL2-expressing EpiSCs contributed to all bodily tissues in chimeric animals while Sox17 + endoderm progenitors specifically contributed in a region-specific fashion to endodermal tissues. In addition, BCL2 expression enabled rat EpiSCs to contribute to mouse embryonic chimeras, thereby forming interspecies chimeras that could survive to adulthood. Our system therefore provides a method to overcome cellular compatibility issues that typically restrict chimera formation. Application of this type of approach could broaden the use of embryonic chimeras, including region-specific chimeras, for basic developmental biology research and regenerative medicine. Copyright © 2016 Elsevier Inc. All rights reserved.

  8. Immune competence of splenic lymphocytes following graft-vs-host disease in mouse allogeneic radiation chimeras

    International Nuclear Information System (INIS)

    Urso, P.; Gengozian, N.

    1977-01-01

    The abnormal immune response of long-term mouse allogeneic chimeras is reflected by qualitative deficiencies in either T or B lymphocytes. The present study was undertaken to determine if a relationship existed between the severity of graft-vs-host disease (GVHD) that these animals had experienced and a functional defect in either the T or B cell population. The in vitro PFC response of chimera spleen cells to sheep red blood cells (SRBC) was evaluated in the presence of normal T or B lymphocytes 4 to 8 months after marrow transplantation and well beyond the GVHD period. In an analysis of several different allogeneic radiation chimeras, our results showed no relationship between the severity of GVHD experienced and the immunologic capacity of either T or B cells. Thus, different chimera combinations showing similar degrees of GVHD were functionally deficient in one or the other of these two cells types or both with no apparent predilection for abnormality in either population. In examining the quantitative in vitro PFC response to sheep RBC by spleen cells from individual chimeras, we found that the number of PFC formed was related to the severity of GVHD experienced by that animal. A general relationship between severity of GVHD and PFC capacity may also exist between chimeras of different genetic combinations. However, this relationship is not precise since gross exceptions occur. Our results, although documenting further the qualitative abnormalities in T and/or B lymphocytes of radiation chimeras, do not reveal the factor or mechanisms by which these cells are made unresponsive. It is suggested that the tolerance-inducing mechanism of these animals, whether it be humoral blocking factors or suppressor cells, is in some way interfering with the collaboration of T and B cells for antibody production

  9. Contribution of Mouse Embryonic Stem Cells and Induced Pluripotent Stem Cells to Chimeras through Injection and Coculture of Embryos

    OpenAIRE

    Guo, Jitong; Wu, Baojiang; Li, Shuyu; Bao, Siqin; Zhao, Lixia; Hu, Shuxiang; Sun, Wei; Su, Jie; Dai, Yanfeng; Li, Xihe

    2014-01-01

    Blastocyst injection and morula aggregation are commonly used to evaluate stem cell pluripotency based on chimeric contribution of the stem cells. To assess the protocols for generating chimeras from stem cells, 8-cell mouse embryos were either injected or cocultured with mouse embryonic stem cells and induced pluripotent stem cells, respectively. Although a significantly higher chimera rate resulted from blastocyst injection, the highest germline contribution resulted from injection of 8-cel...

  10. A chimera embryo assay reveals a decrease in embryonic cellular proliferation induced by sperm from X-irradiated male mice

    International Nuclear Information System (INIS)

    Obasaju, M.F.; Wiley, L.M.; Oudiz, D.J.; Raabe, O.; Overstreet, J.W.

    1989-01-01

    Male mice were divided into three experimental groups and a control group. Mice in the experimental groups received one of three doses of acute X irradiation (1.73, 0.29, and 0.05 Gy) and together with the control unirradiated mice were then mated weekly to unirradiated female mice for a 9-week experimental period. Embryos were recovered from the weekly matings at the four-cell stage and examined by the chimera assay for proliferative disadvantage. Aggregation chimeras were constructed of embryos from female mice mated to irradiated males (experimental embryos) and embryos from females mated to unexposed males (control embryos) and contained either one experimental embryo and one control embryo (heterologous chimera) or two control embryos (control chimera). The control embryo in heterologous chimeras and either embryo in control chimeras were prelabeled with the vital dye fluorescein isothiocyanate (FITC), and the chimeras were cultured for 40 h and viewed under phase-contrast and epifluorescence microscopy to obtain total embryo cell number and the cellular contribution from the FITC-labeled embryo. Experimental and control embryos that were cultured singly were also examined for embryo cell number at the end of the 40-h culture period. In control chimeras, the mean ratio of the unlabeled cells:total chimera cell number (henceforth referred to as ''mean ratio'') was 0.50 with little or no weekly variation over the 9-week experimental period. During Weeks 4-7, the mean ratios of heterologous chimeras differed significantly from the mean ratio of control chimeras with the greatest differences occurring during Week 7 (0.41 for chimeras of 0.05 Gy dose group, 0.40 for chimeras of the 0.29 Gy dose group, and 0.17 for chimeras of the 1.73 Gy dose group)

  11. Germline competence of mouse ES and iPS cell lines: Chimera technologies and genetic background.

    Science.gov (United States)

    Carstea, Ana Claudia; Pirity, Melinda K; Dinnyes, Andras

    2009-12-31

    In mice, gene targeting by homologous recombination continues to play an essential role in the understanding of functional genomics. This strategy allows precise location of the site of transgene integration and is most commonly used to ablate gene expression ("knock-out"), or to introduce mutant or modified alleles at the locus of interest ("knock-in"). The efficacy of producing live, transgenic mice challenges our understanding of this complex process, and of the factors which influence germline competence of embryonic stem cell lines. Increasingly, evidence indicates that culture conditions and in vitro manipulation can affect the germline-competence of Embryonic Stem cell (ES cell) lines by accumulation of chromosome abnormalities and/or epigenetic alterations of the ES cell genome. The effectiveness of ES cell derivation is greatly strain-dependent and it may also influence the germline transmission capability. Recent technical improvements in the production of germline chimeras have been focused on means of generating ES cells lines with a higher germline potential. There are a number of options for generating chimeras from ES cells (ES chimera mice); however, each method has its advantages and disadvantages. Recent developments in induced pluripotent stem (iPS) cell technology have opened new avenues for generation of animals from genetically modified somatic cells by means of chimera technologies. The aim of this review is to give a brief account of how the factors mentioned above are influencing the germline transmission capacity and the developmental potential of mouse pluripotent stem cell lines. The most recent methods for generating specifically ES and iPS chimera mice, including the advantages and disadvantages of each method are also discussed.

  12. EXAMINATION OF THE GERM CELL CHIMERA FORMING POTENTIAL OF MOUSE EMBRYONIC STEM CELLS

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    V.B. CÂRSTEA

    2007-05-01

    Full Text Available The aim of this study was to examine the factors, which influence the chimeraforming potential of mouse embryonic stem cells (ES cells. In our work, we examinethe chimera producing ability of R1 and R1/E mouse ES cell lines. We found that thepassage number affects chimera-forming capability of the ES cells. With theincreasing of the passage number, it could be getting less chimera animal, and onlythe R1/E ES cell line derived cells could contribute to the germ cells. At first, wecompared the marker of pluripotency using immunostaining and RT PCR, but wecould not find any difference between the R1 and R1/E cell in this way. Atchromosome analysis, we found, that the number of aneuploid cells, in R1 ES cellline, dramatically increased after 10 passages. We thought that the reason is thatduring the cell division Y chromosome could not arrange correctly between the twonewly derived progeny cells. To prove our conception, we made X and YchromosomeFISH analyses. We found, that the aneuploid R1 and R1/E ES cellscontain only one X and one Y chromosome, so not the loss of Y chromosome causethe problem at the germ cell formation. At last, we made the karyotypeanalysis of R1 and R1/E ES cells at different passages. The karyotype analysisdemonstrated that in the case of R1 ES cell line, the 41 and 42-chromosomecontaining cells hold trisomy. With the increasing of the passages number, thenumber of trisomy containing aneuploid cells increased. The aneuploid ES cells cancontribute to the different tissuses of chimera animals, but cannot form viable germcells.

  13. EXAMINATION OF THE GERM CELL CHIMERA FORMING POTENTIAL OF MOUSE EMBRYONIC STEM CELLS

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    CÂRSTEA V. B

    2007-01-01

    Full Text Available The aim of this study was to examine the factors, which influence the chimeraforming potential of mouse embryonic stem cells (ES cells. In our work, we examinethe chimera producing ability of R1 and R1/E mouse ES cell lines. We found that thepassage number affects chimera-forming capability of the ES cells. With theincreasing of the passage number, it could be getting less chimera animal, and onlythe R1/E ES cell line derived cells could contribute to the germ cells. At first, wecompared the marker of pluripotency using immunostaining and RT PCR, but wecould not find any difference between the R1 and R1/E cell in this way. Atchromosome analysis, we found, that the number of aneuploid cells, in R1 ES cellline, dramatically increased after 10 passages. We thought that the reason is thatduring the cell division Y chromosome could not arrange correctly between the twonewly derived progeny cells. To prove our conception, we made X and YchromosomeFISH analyses. We found, that the aneuploid R1 and R1/E ES cellscontain only one X and one Y chromosome, so not the loss of Y chromosome causethe problem at the germ cell formation. At last, we made the karyotypeanalysis of R1 and R1/E ES cells at different passages. The karyotype analysisdemonstrated that in the case of R1 ES cell line, the 41 and 42-chromosomecontaining cells hold trisomy. With the increasing of the passages number, thenumber of trisomy containing aneuploid cells increased. The aneuploid ES cells cancontribute to the different tissuses of chimera animals, but cannot form viable germcells.

  14. Radiation-induced mouse chimeras: a cellular analysis of the major lymphoid compartments, factors affecting lethal graft versus host disease and host-tumor interactions

    International Nuclear Information System (INIS)

    Almaraz, R.

    1981-01-01

    The major lymphoid compartments of allogeneic bone marrow chimeras were evaluated for the extent of cell chimerism and distribution of Thy 1 and la bearing cells. These chimeras contained lymphoid cell primarily of donor origin. The bone marrow compartment was a mixture of host and donor origin cells. The distribution of Thy 1 and la bearing cells was similar as in normal mice. The effect of adult thymectomy alone or followed by whole-body irradiation and bone marrow reconstitution on the distribution of the Thy 1 positive cells was also investigated. Thymectomy with or without WBI and bone marrow reconstitution significantly lowered the number of Thy 1 bearing cells in the blood and spleen. The number of la bearing cells did not appear to be affected by thymectomy. The role of circulating lymphoid cells in the incidence of lethal graft versus host disease (GVHD) in radiation induced fully allogeneic mouse chimeras was studied. Mice reconstituted with allogeneic bone marrow from bled donors had a statistically lower incidence of GVHD than those reconstituted with bone marrow from unbled donors. Addition of mature peripheral lymphocytes from blood to the reconstituting bone marrow cells from bled donors reduplicated the high incidence of lethal GVHD. It was demonstrated that the bone marrow of mice not exsanguinated prior to harvesting of bone marrow contained significant numbers of peripheral contaminating cells in the harvested bone marrow. The role of suppressor cell elimination in resisting tumor growth was investigated using radiation induced mouse chimeras. Local effects of irradiation alone at the site of tumor inoculation could account for this lack of growth

  15. The use of the mouse chimera assay to detect early embryonic damage from male mice exposed to low-dose radiation

    International Nuclear Information System (INIS)

    Oudiz, D.; Warner, P.; Walsh, K.J.; Wiley, L.

    1990-01-01

    Mouse chimeras are in vitro aggregations of two 4-cell embryos and are used to detect subtle, nonlethal changes, which are expressed as a proliferative disadvantage in exposed embryos. One of the embryos is labeled with a viable dye (FITC) in order to determine the relative cellular contribution of each embryo when the chimera is dissociated 40 hours later. This proliferative disadvantage has been seen at doses which do not produce an effect on cell number when the embryos are cultured singly. Previously, the assay has detected a decrease in cellular proliferation in embryos from male mice exposed to a single dose of x-radiation as low as 0.05 Gy. In the current study, male mice were irradiated with a single dose of 0, 0.001, 0.01, or 0.05 Gy, and then serially mated for the next 8 weeks to unexposed females. Chimeras were constructed from control and treated embryos. Embryos from males treated with 0.05 Gy exhibited a significant decrease in cellular proliferation during weeks 6 and 7 post-irradiation. A similar decrease was seen in the males treated with 0.01 Gy. No reductions were observed from embryos cultured singly in any of the treatment groups

  16. Interspecies chimera between primate embryonic stem cells and mouse embryos: monkey ESCs engraft into mouse embryos, but not post-implantation fetuses.

    Science.gov (United States)

    Simerly, Calvin; McFarland, Dave; Castro, Carlos; Lin, Chih-Cheng; Redinger, Carrie; Jacoby, Ethan; Mich-Basso, Jocelyn; Orwig, Kyle; Mills, Parker; Ahrens, Eric; Navara, Chris; Schatten, Gerald

    2011-07-01

    Unequivocal evidence for pluripotency in which embryonic stem cells contribute to chimeric offspring has yet to be demonstrated in human or nonhuman primates (NHPs). Here, rhesus and baboons ESCs were investigated in interspecific mouse chimera generated by aggregation or blastocyst injection. Aggregation chimera produced mouse blastocysts with GFP-nhpESCs at the inner cell mass (ICM), and embryo transfers (ETs) generated dimly-fluorescencing abnormal fetuses. Direct injection of GFP-nhpESCs into blastocysts produced normal non-GFP-fluorescencing fetuses. Injected chimera showed >70% loss of GFP-nhpESCs after 21 h culture. Outgrowths of all chimeric blastocysts established distinct but separate mouse- and NHP-ESC colonies. Extensive endogenous autofluorescence compromised anti-GFP detection and PCR analysis did not detect nhpESCs in fetuses. NhpESCs localize to the ICM in chimera and generate pregnancies. Because primate ESCs do not engraft post-implantation, and also because endogenous autofluorescence results in misleading positive signals, interspecific chimera assays for pluripotency with primate stem cells is unreliable with the currently available ESCs. Testing primate ESCs reprogrammed into even more naïve states in these inter-specific chimera assays will be an important future endeavor. Copyright © 2011 Elsevier B.V. All rights reserved.

  17. Antiviral T cell competence and restriction specificity of mixed allogeneic (P1 + P2----P1) irradiation chimeras

    International Nuclear Information System (INIS)

    Rueedi, E.S.; Sykes, M.; Ildstad, S.T.; Chester, C.H.; Althage, A.; Hengartner, H.; Sachs, D.H.; Zinkernagel, R.M.

    1989-01-01

    Mixed irradiation bone marrow chimeras were prepared by reconstituting lethally irradiated C57BL/10 (B10) or B10.D2 mice with T cell-depleted bone marrow cells of B10 plus B10.D2 origin. These chimeras were healthy and survived well under conventional housing conditions and after experimental laboratory infections. Of a total of 17 chimeras tested, 2 died spontaneously or from the injected virus. Twelve of fifteen chimeras mounted a measurable cytotoxic T cell response to virus. Despite approximately equal percentages of B10 and B10.D2 lymphocytes in chimeras, cytotoxic T cell responses to vaccinia virus and lymphocytic choriomeningitis virus were mediated variably by either syngeneic or allogeneic donor lymphocytes; thus the H-2 type of effector T cells frequently did not correspond to the 50:50 distribution of spleen or peripheral blood lymphocytes. Cytotoxic responses were restricted exclusively to recipient H-2 type. All mixed chimeras examined were able to mount a good IgG response to vesicular stomatitis virus. These results confirm previous data suggesting that such mixed chimeras are healthy and immunocompetent and demonstrate strict recipient-determined restriction specificity of effector T cells; they also suggest that if T help is necessary for induction of virus-specific cytotoxic T cells, it does not require host-restricted interactions between helper T cells and precursor cytotoxic T cells

  18. Nonspecific suppressor elements in murine allogeneic radiation chimeras

    International Nuclear Information System (INIS)

    Urso, P.; Gengozian, N.

    1979-01-01

    Spleen cells from long-term mouse allogeneic radiation chimeras were tested for their ability to modulate the graft-versus-host (GVH) or plaque-forming cell (PFC) response of normal lymphocytes transplanted in lethally x-irradiated recipients. In vivo GVH proliferation of normal lymphocytes (syngeneic to donor cells of the chimera) against antigens of host-type in which the chimeric state had been established was reduced by chimera cells. Inhibition varied, some chimeras suppressing GVH more than others and a few not suppressing at all. The suppressive effect was abrogated if the chimera cells were treated with anti-THETA; treatment with anti-IgM did not eliminate this activity. When mixtures of normal donor lymphocytes and chimera cells were given to irradiated recipients genetically different from host or donor, reduction of donor cell GVH also occurred. Further, chimera cells reduced the GVH activity of normal host cells in irradiated recipients differing from the host at one H-2 locus and from the donor at minor histocompatibility loci. The modulating effect of spleen cells from chimeras on the PFC response by normal lymphocytes also varied. Six chimeras induced a 25 to 90% suppression, two enhanced the response, and one showed no effect. Where suppression occurred, treatment of chimera cells with anti-THETA most often, but not always, restored PFC production. Our results show that the suppressive action of splenic lymphoid cells by chimeras is highly nonspecific and variable in expression. We suggest that tolerance in chimeras may be mediated by nonspecific suppressor elements leading to unresponsiveness to a variety of antigens including SRBC

  19. Characteristics of macrophages in irradiation chimeras in mice reconstituted with allogeneic bone marrow cells

    International Nuclear Information System (INIS)

    Yasumizu, R.; Onoe, K.; Iwabuchi, K.; Ogasawara, M.; Fujita, M.; Okuyama, H.; Good, R.A.; Morikawa, K.

    1985-01-01

    Biological and immunological characteristics of the reticuloendothelial system of irradiation bone marrow chimeric mice and macrophages collected from various tissue sources of the mice were studied. The chimeras showed comparable activities in carbon clearance to those of normal donor or recipient mice. The macrophages from spleen, lymph node, bone marrow, peripheral blood, liver, peritoneal cavity, and lung were demonstrated to be of donor marrow origin. They showed almost the same enzyme activities and phagocytic capability of sheep erythrocytes (SRBC, E), SRBC sensitized with anti-SRBC IgG (EA), and SRBC sensitized with anti-SRBC IgM and coated with complement (EAC) as those of normal mice. Proportions of Fc receptor and complement receptor-positive cells are also in normal range. In addition, the antigen-presenting capability of the chimeric macrophages for in vitro primary antibody response to SRBC was intact. These observations suggest that the reticuloendothelial system and macrophages of allogeneic bone marrow chimeras where donor and recipient differ at the major histocompatibility complex have no defect so far as could be ascertained by the present study

  20. Inherited effects from mouse immature oocytes following low-dose irradiation

    International Nuclear Information System (INIS)

    Straume, T.; Khan, R.; Raabe, O.G.; Walsh, K.J.; Wiley, L.M.

    1992-07-01

    Immature oocytes represent the genetic pool in female mice as well as in women and therefore are principal cells of concern for genetic studies. Previous studies have demonstrated that genetic effects in female mice can be masked by the hypersensitive plasma membrane lethality target of immature oocytes. Studies have also shown that genetic effects can be detected when the plasma mambrane is sufficiently spared. Here, new data obtained using the mouse preimplantation embryo chimera assay are presented and discussed in light of previous findings for irradiated mouse oocytes

  1. Early dominance of irradiated host cells in the responder profiles of thymocytes from P → F1 radiation chimeras

    International Nuclear Information System (INIS)

    Korngold, R.; Bennink, J.R.; Doherty, P.C.

    1981-01-01

    The number of cells in the thymus of radiation (1000 rad) chimeras increases approximately 10-fold between 7 and 14 days after reconstitution with bone marrow. At least 50% of the cells in thymus on day 14 are of host origin and respond to virus presented in the context of both H-2/sup k/ and H-2/sup b/ when primed in irradiated, virus-infected (b x k)F 1 recipients. Strong CTL responses can be generated from thymocytes of donor origin on day 21. All evidence of a significant host thymocyte component has disappeared by day 28. The responsiveness of 14-day thymocytes is not abrogated by pretreatment of the mice used to make the chimeras with anti-thymocyte serum or by using doses of irradiation as high as 1200 rads to eliminate host components

  2. Thymectomized, irradiated, and bone marrow-reconstituted chimeras have normal cytolytic T lymphocyte precursors but a defect in lymphokine production

    International Nuclear Information System (INIS)

    Duprez, V.; Maziarz, R.; Weinberger, O.; Burakoff, S.J.

    1984-01-01

    A model system has been developed to study extrathymic T cell differentiation; mice have been thymectomized, lethally irradiated, and reconstituted with bone marrow cells depleted of Thy-1 + cells. After 8 wk, the spleen cells of these athymic, bone marrow-reconstituted chimeras contain Thy-1 + precytolytic T lymphocytes (CTL) that are able to respond to antigen only if supernatant from Con A-activated T cells is added to culture. The phenotype of these pre-CTL is similar to that of thymocytes, suggesting that they may be immature T cells. Initial evaluation of the CTL repertoire of these athymic mice demonstrated that the CTL generated to trinitrophenyl-modified syngeneic cells are H-2-restricted, and that the CTL generated to alloantigens have many of the cross-reactivities observed in normal mice but not in nude mice. In this report, the authors demonstrate a helper T cell defect in these thymectomized chimeras. These chimeras lack an Ly-1 + helper cell required for thymocytes to differentiate to CTL. Further studies revealed that when spleen cells from these thymectomized chimeras were stimulated with Con A, they produced normal levels of interleukin 2. However, these splenocytes were defective in the production of another factor needed for CTL differentiation

  3. Functional clonal deletion versus suppressor cell-induced transplantation tolerance in chimeras prepared with a short course of total-lymphoid irradiation

    International Nuclear Information System (INIS)

    Slavin, S.; Morecki, S.; Weigensberg, M.; Bar, S.; Weiss, L.

    1986-01-01

    Allogeneic bone marrow (BM) chimeras induced by infusion of BM cells into recipients conditioned with total lymphoid irradiation (TLI) were shown to develop humoral and cell-mediated tolerance to host and donor-type alloantigens by a number of in vitro and in vivo assays. Spleen cells of tolerant chimeras exhibited suppressive activity of mixed lymphocyte reaction (MLR). MLR suppression was not abrogated by depletion of Lyt-2 cells, and neither could Lyt-2-positive cells sorted from the spleens of tolerant chimeras suppress MLR or attenuate graft-versus-host reactivity in vivo. Likewise, specifically unresponsive spleen cells obtained from chimeras could not be induced to respond in MLR against tolerizing host-type cells following depletion of Lyt-2 or passage through a nylon-wool column. Tolerance of chimera spleen cells to host alloantigens, best documented by permanent survival of donor-type skin allografts, could be adoptively transferred into syngeneic recipients treated by heavy irradiation but not into untreated or mildly irradiated recipients. Adoptive transfer of tolerance seemed to be associated with experimental conditions favoring engraftment of tolerant cells rather than suppression of host reactivity. We speculate that although host and/or donor-derived suppressor cells may be operating in reducing the pool of specific alloreactive clones by blocking cell proliferation in response to allogeneic challenge, the final outcome in tolerant chimeras is actual or functional deletion of alloreactive clones

  4. Human iPSC Glial Mouse Chimeras Reveal Glial Contributions to Schizophrenia

    DEFF Research Database (Denmark)

    Windrem, Martha S.; Osipovitch, Mikhail; Liu, Zhengshan

    2017-01-01

    with childhood-onset SCZ. After neonatal implantation into myelin-deficient shiverer mice, SCZ GPCs showed premature migration into the cortex, leading to reduced white matter expansion and hypomyelination relative to controls. The SCZ glial chimeras also showed delayed astrocytic differentiation and abnormal...... astrocytic morphologies. When established in myelin wild-type hosts, SCZ glial mice showed reduced prepulse inhibition and abnormal behavior, including excessive anxiety, antisocial traits, and disturbed sleep. RNA-seq of cultured SCZ human glial progenitor cells (hGPCs) revealed disrupted glial...

  5. Deficiency in early development of the thymus-dependent cells in irradiation chimeras attributable to recipient's environment

    International Nuclear Information System (INIS)

    Iwabuchi, C.; Iwabuchi, K.; Kobayashi, S.; Ogasawara, K.; Negishi, I.; Wang, B.Y.; Wambua, P.P.; Arase, H.; Fukushi, N.; Itoh, Y.

    1991-01-01

    Bone marrow chimeras were prepared using reciprocal combinations of AKR and C3H mice. When C3H mice were recipients, the number of thymocytes recoverable from such chimeras (C3H recipient chimeras) was small as compared with that from chimeras for which AKR mice were used as recipients (AKR recipient chimeras) regardless of donor strain. The thymocytes from C3H recipient chimeras showed a profound deficiency in generating proliferative responses to stimulation by anti-CD3 mAb (2C11) or anti-TCR (alpha, beta) mAb (H57-597), even though the expression of CD3 and TCR molecules fell within the same range as that in AKR recipient chimeras. Furthermore, after stimulation with immobilized 2C11, the proportion of IL-2R+ cells in the thymocytes from C3H recipient chimeras was much less than that in AKR recipient chimeras. However, no significant difference in proliferative responses to 2C11 plus PMA, in influx of Ca2+ after stimulation with 2C11 or IL-2 production in response to 2C11 plus PMA or PMA plus A23187 was demonstrated between C3H and AKR recipient chimeras. These findings suggest that the thymocytes from C3H recipient chimeras have a deficiency in the signal transduction system as compared with chimeras for which AKR mice are the recipients. The thymic stromal component involved in this difference in the C3H recipient chimeras is discussed

  6. Late effects of irradiation in mouse jejunum

    International Nuclear Information System (INIS)

    Reynaud, A.; Travis, E.L.

    1984-01-01

    The response of mouse jejunum at intervals up to 1 year after single 'priming' doses of X-rays has been assessed by crypt survival after retreatment with single doses of X-rays and morphometric analysis of changes in the intestinal submucosa. The crypt dose-survival curves in mice re-irradiated at 2, 6, or 12 months after priming irradiation were displaced to higher doses in pre-treated than in non-pre-treated mice and were characterized by higher D 0 values. Misonidazole given before the test exposure reversed this effect so that the dose survival curve for crypts in pre-treated mice were superimposed on that for mice not previously irradiated, suggesting that the increase in isoeffect dose and the change in the D 0 in previously exposed mice was due to crypt hypoxia. Quantifications of the area of the submucosa showed that its area was increased at all three times after the priming doses and was a result of collagen deposition and oedema. Thus, the hypoxia in the crypts was probably secondary to these changes. Deaths began at 6-7 months after priming irradiation and were due to intestinal obstruction and stenosis. Thus, as in other tissues, two phases of injury can be assayed in the intestine of experimental animals. (author)

  7. Cytogenetics of Post-Irradiation Mouse Leukaemia

    Energy Technology Data Exchange (ETDEWEB)

    Wald, N.; Pan, S.; Upton, A.; Brown, R. [Graduate School of Public Health, University of Pittsburgh, PA (United States); Oak Ridge National Laboratory, Oak Ridge, TN (United States)

    1969-11-15

    The interrelationship between radiation, cytogenetic abnormalities, and viruses in leukaemogenesis has been studied in the RF/Un mouse which develops a high incidence of granulocytic leukaemia on radiation exposure. A virus-like agent has been demonstrated in such leukaemic animals and the disease has been transmitted by passage of apparently acellular materials from irradiated primary animals to normal recipients. Pilot cytogenetic studies revealed consistent abnormal chromosome markers and modal shifts in both irradiated leukaemic animals and in non-irradiated animals developing leukaemia after passage injection. To define better the relationship between consistent bone-marrow chromosome aberrations and postirradiation primary and passaged leukaemia, 100 RF/Un mice were studied which were irradiated with 300 R of 250-kVp X-rays at 100 weeks of age and subsequently developed leukaemia. Eighty-seven had granulocytic leukaemia and in 72 of these, bone-marrow cytogenetic abnormalities were found. The distribution of-numerical and structural chromosome aberrations in 3225 cells studied are reviewed in derail. The correlation of specific aberrations to clinical and histopathologic findings has been attempted: Sequential passages of apparently cell-free material from the post-irradiation leukaemic mice into unirradiated RE/Un recipients and subsequent passages from leukaemic recipients were performed to observe the evolution of any initial chromosome markers and shifts in modal chromosome number in the passage generations. Two-hundred-thirty-six mice were inoculated with the material obtained either from primary post-irradiation leukaemic mice or from serially-passaged leukaemia cases. In the most extensive passaged line, 22 transfer generations containing 129 leukaemic mice were examined by clinical, histopathologic, -haematologic and cytogenetic procedures. Evolution of abnormal chromosome modes from 41 in the early passages to 39 chromosomes consistently after the 4

  8. Resistance to infection with Eimeria vermiformis in mouse radiation chimeras is determined by donor bone-marrow cells

    International Nuclear Information System (INIS)

    Joysey, H.S.; Wakelin, D.; Rose, M.E.

    1988-01-01

    The course of infection with Eimeria vermiformis was determined in BALB/b, BALB/c, and C57BL/10ScSn (B10) mice and in radiation chimeras prepared from the H-2-compatible BALB/b and B10 mice. The BALB strains, irrespective of H-2 haplotype, were resistant, the B10 mice were susceptible, and in the chimeras infection was characterized by the genotype of the donated bone-marrow cells and not by the phenotype of the recipient. Thus, the genetic control of relative resistance or susceptibility to infection with this parasite is expressed through bone-marrow-derived cells

  9. Interaction of X-irradiated mouse cells in heterokaryons

    International Nuclear Information System (INIS)

    Hofmanova, J.; Spurna, V.

    1985-01-01

    The frequency of heterokaryon formation and the ability of DNA synthesis in the system of mouse X-irradiated L fibroblasts and non-irradiated or irradiated LS/BL lymphosarcoma cells were studied. The frequency of heterokaryons after fusion of one or both irradiated parental cells was 3 to 6 times higher than in the non-irradiated cell cultures. In these heterokaryons we found 1.5 to 3 times more nuclei of irradiated L cells capable of DNA synthesis than in the population of non-fused irradiated cells. (author)

  10. Specific tolerance induction across a xenogeneic barrier: Production of mixed rat/mouse lymphohematopoietic chimeras using a nonlethal preparative regimen

    International Nuclear Information System (INIS)

    Sharabi, Y.; Aksentijevich, I.; Sundt, T.M. III; Sachs, D.H.; Sykes, M.

    1990-01-01

    The development of safe methods for inducing donor-specific tolerance across xenogeneic barriers could potentially relieve the critical shortage of allograft donors that currently limits the applicability of organ transplantation. We report here that such tolerance can be induced in a xenogeneic combination (rat----mouse) using a nonmyeloablative and nonlethal preparative regimen. Successful induction of chimerism and donor-specific transplantation tolerance required pretreatment of recipients with monoclonal antibodies (mAbs) against NK1.1, Thy-1.2, CD4 and CD8, followed by administration of 3 Gy whole body radiation (WBI), 7 Gy thymic irradiation, and infusion of T cell-depleted rat bone marrow cells (BMC). Rat cells appeared among peripheral blood lymphocytes (PBL) of such recipients by 2-3 wk, and rat T cells by 2-5 wk following bone marrow transplantation (BMT). Donor-type rat skin grafts placed 4 mo after BMT were accepted, while simultaneously placed non-donor-type rat skin grafts were promptly rejected. In addition to its clinical potential, the ability to induce donor-specific tolerance across xenogeneic barriers using such a nonlethal preparative regimen provides a valuable model for the study of mechanisms of xenogeneic transplantation tolerance

  11. Growth regulation in X-irradiated mouse skin

    International Nuclear Information System (INIS)

    Elgjo, K.; Devik, F.

    1978-01-01

    Extracts of hairless mouse skin were tested for their content of epidermal G 1 inhibitor and G 2 inhibitor at daily intervals after X-irradiation with 4 500 or 2 250 rad. After either dose the skin extracts lacked G 1 inhibitory activity on days 5 and 6 respectively after irradiation. This coincided with the time when the epidermal mitotic rate again became normal and started a period of over-shoot. The time interval of 5 to 6 days corresponds to the turnover time of the differentiating cells in hairless mouse back epidermis. The findings indicate that the proliferating cells in epidermis can respond to changes in local chalone concentration, even after X-irradiation at the tested doses, and that the irradiated epidermal cell population still retains some important properties inherent in a cybernetically regulated system. The local G 2 -inhibitory activity also varied after irradiation, but these variations could not be directly related to the corresponding mitotic rates. (author)

  12. Chronic Exposure to Androgenic-Anabolic Steroids Exacerbates Axonal Injury and Microgliosis in the CHIMERA Mouse Model of Repetitive Concussion.

    Directory of Open Access Journals (Sweden)

    Dhananjay R Namjoshi

    Full Text Available Concussion is a serious health concern. Concussion in athletes is of particular interest with respect to the relationship of concussion exposure to risk of chronic traumatic encephalopathy (CTE, a neurodegenerative condition associated with altered cognitive and psychiatric functions and profound tauopathy. However, much remains to be learned about factors other than cumulative exposure that could influence concussion pathogenesis. Approximately 20% of CTE cases report a history of substance use including androgenic-anabolic steroids (AAS. How acute, chronic, or historical AAS use may affect the vulnerability of the brain to concussion is unknown. We therefore tested whether antecedent AAS exposure in young, male C57Bl/6 mice affects acute behavioral and neuropathological responses to mild traumatic brain injury (TBI induced with the CHIMERA (Closed Head Impact Model of Engineered Rotational Acceleration platform. Male C57Bl/6 mice received either vehicle or a cocktail of three AAS (testosterone, nandrolone and 17α-methyltestosterone from 8-16 weeks of age. At the end of the 7th week of treatment, mice underwent two closed-head TBI or sham procedures spaced 24 h apart using CHIMERA. Post-repetitive TBI (rTBI behavior was assessed for 7 d followed by tissue collection. AAS treatment induced the expected physiological changes including increased body weight, testicular atrophy, aggression and downregulation of brain 5-HT1B receptor expression. rTBI induced behavioral deficits, widespread axonal injury and white matter microgliosis. While AAS treatment did not worsen post-rTBI behavioral changes, AAS-treated mice exhibited significantly exacerbated axonal injury and microgliosis, indicating that AAS exposure can alter neuronal and innate immune responses to concussive TBI.

  13. Chronic Exposure to Androgenic-Anabolic Steroids Exacerbates Axonal Injury and Microgliosis in the CHIMERA Mouse Model of Repetitive Concussion.

    Science.gov (United States)

    Namjoshi, Dhananjay R; Cheng, Wai Hang; Carr, Michael; Martens, Kris M; Zareyan, Shahab; Wilkinson, Anna; McInnes, Kurt A; Cripton, Peter A; Wellington, Cheryl L

    2016-01-01

    Concussion is a serious health concern. Concussion in athletes is of particular interest with respect to the relationship of concussion exposure to risk of chronic traumatic encephalopathy (CTE), a neurodegenerative condition associated with altered cognitive and psychiatric functions and profound tauopathy. However, much remains to be learned about factors other than cumulative exposure that could influence concussion pathogenesis. Approximately 20% of CTE cases report a history of substance use including androgenic-anabolic steroids (AAS). How acute, chronic, or historical AAS use may affect the vulnerability of the brain to concussion is unknown. We therefore tested whether antecedent AAS exposure in young, male C57Bl/6 mice affects acute behavioral and neuropathological responses to mild traumatic brain injury (TBI) induced with the CHIMERA (Closed Head Impact Model of Engineered Rotational Acceleration) platform. Male C57Bl/6 mice received either vehicle or a cocktail of three AAS (testosterone, nandrolone and 17α-methyltestosterone) from 8-16 weeks of age. At the end of the 7th week of treatment, mice underwent two closed-head TBI or sham procedures spaced 24 h apart using CHIMERA. Post-repetitive TBI (rTBI) behavior was assessed for 7 d followed by tissue collection. AAS treatment induced the expected physiological changes including increased body weight, testicular atrophy, aggression and downregulation of brain 5-HT1B receptor expression. rTBI induced behavioral deficits, widespread axonal injury and white matter microgliosis. While AAS treatment did not worsen post-rTBI behavioral changes, AAS-treated mice exhibited significantly exacerbated axonal injury and microgliosis, indicating that AAS exposure can alter neuronal and innate immune responses to concussive TBI.

  14. Acute serum amyloid A induces migration, angiogenesis, and inflammation in synovial cells in vitro and in a human rheumatoid arthritis/SCID mouse chimera model.

    LENUS (Irish Health Repository)

    Connolly, Mary

    2010-06-01

    Serum amyloid A (A-SAA), an acute-phase protein with cytokine-like properties, is expressed at sites of inflammation. This study investigated the effects of A-SAA on chemokine-regulated migration and angiogenesis using rheumatoid arthritis (RA) cells and whole-tissue explants in vitro, ex vivo, and in vivo. A-SAA levels were measured by real-time PCR and ELISA. IL-8 and MCP-1 expression was examined in RA synovial fibroblasts, human microvascular endothelial cells, and RA synovial explants by ELISA. Neutrophil transendothelial cell migration, cell adhesion, invasion, and migration were examined using transwell leukocyte\\/monocyte migration assays, invasion assays, and adhesion assays with or without anti-MCP-1\\/anti-IL-8. NF-kappaB was examined using a specific inhibitor and Western blotting. An RA synovial\\/SCID mouse chimera model was used to examine the effects of A-SAA on cell migration, proliferation, and angiogenesis in vivo. High expression of A-SAA was demonstrated in RA patients (p < 0.05). A-SAA induced chemokine expression in a time- and dose-dependent manner (p < 0.05). Blockade with anti-scavenger receptor class B member 1 and lipoxin A4 (A-SAA receptors) significantly reduced chemokine expression in RA synovial tissue explants (p < 0.05). A-SAA induced cell invasion, neutrophil-transendothelial cell migration, monocyte migration, and adhesion (all p < 0.05), effects that were blocked by anti-IL-8 or anti-MCP-1. A-SAA-induced chemokine expression was mediated through NF-kappaB in RA explants (p < 0.05). Finally, in the RA synovial\\/SCID mouse chimera model, we demonstrated for the first time in vivo that A-SAA directly induces monocyte migration from the murine circulation into RA synovial grafts, synovial cell proliferation, and angiogenesis (p < 0.05). A-SAA promotes cell migrational mechanisms and angiogenesis critical to RA pathogenesis.

  15. The response of previously irradiated mouse skin to heat alone or combined with irradiation: influence of thermotolerance

    NARCIS (Netherlands)

    Wondergem, J.; Haveman, J.

    1983-01-01

    The skin of the mouse foot was used to study the effects of previous irradiation on the response to hyperthermia (44 degrees C), to irradiation, or to irradiation combined with hyperthermia (43 degrees C or 44 degrees C). Hyperthermia was applied by immersing the mouse foot into a hot waterbath and

  16. Bat-mouse bone marrow chimera: a novel animal model for dissecting the uniqueness of the bat immune system.

    Science.gov (United States)

    Yong, Kylie Su Mei; Ng, Justin Han Jia; Her, Zhisheng; Hey, Ying Ying; Tan, Sue Yee; Tan, Wilson Wei Sheng; Irac, Sergio Erdal; Liu, Min; Chan, Xue Ying; Gunawan, Merry; Foo, Randy Jee Hiang; Low, Dolyce Hong Wen; Mendenhall, Ian Hewitt; Chionh, Yok Teng; Dutertre, Charles-Antoine; Chen, Qingfeng; Wang, Lin-Fa

    2018-03-16

    Bats are an important animal model with long lifespans, low incidences of tumorigenesis and an ability to asymptomatically harbour pathogens. Currently, in vivo studies of bats are hampered due to their low reproduction rates. To overcome this, we transplanted bat cells from bone marrow (BM) and spleen into an immunodeficient mouse strain NOD-scid IL-2R -/- (NSG), and have successfully established stable, long-term reconstitution of bat immune cells in mice (bat-mice). Immune functionality of our bat-mouse model was demonstrated through generation of antigen-specific antibody response by bat cells following immunization. Post-engraftment of total bat BM cells and splenocytes, bat immune cells survived, expanded and repopulated the mouse without any observable clinical abnormalities. Utilizing bat's remarkable immunological functions, this novel model has a potential to be transformed into a powerful platform for basic and translational research.

  17. Gene expression profiles of mouse spermatogenesis during recovery from irradiation

    DEFF Research Database (Denmark)

    Shah, Fozia J; Tanaka, Masami; Nielsen, John E

    2009-01-01

    BACKGROUND: Irradiation or chemotherapy that suspend normal spermatogenesis is commonly used to treat various cancers. Fortunately, spermatogenesis in many cases can be restored after such treatments but knowledge is limited about the re-initiation process. Earlier studies have described the cell......BACKGROUND: Irradiation or chemotherapy that suspend normal spermatogenesis is commonly used to treat various cancers. Fortunately, spermatogenesis in many cases can be restored after such treatments but knowledge is limited about the re-initiation process. Earlier studies have described...... the cellular changes that happen during recovery from irradiation by means of histology. We have earlier generated gene expression profiles during induction of spermatogenesis in mouse postnatal developing testes and found a correlation between profiles and the expressing cell types. The aim of the present...... work was to utilize the link between expression profile and cell types to follow the cellular changes that occur during post-irradiation recovery of spermatogenesis in order to describe recovery by means of gene expression. METHODS: Adult mouse testes were subjected to irradiation with 1 Gy...

  18. Functional State of Haemopoietic Stem Cells in the Irradiated Mouse

    Energy Technology Data Exchange (ETDEWEB)

    Silini, G.; Pozzi, Laura V. [Laboratorio di Radiobiologica Animale, Centro Studi Nucleari, Casaccia, Rome (Italy)

    1968-08-15

    The repopulation kinetics of bone marrow in irradiated (C3H x C57BL) F{sub 1} hybrid mice were followed at different time intervals after a single whole-body dose of 150 rad X -rays. The changes in the number of total nucleated cells and of colony-forming cells were estimated and expressed as number of cells per femur shaft of fixed length. For the evaluation of the progenitor cell compartment an exogenous test of transplantation into heavily irradiated hosts followed by spleen colony counts was employed. In an attempt to distinguish between cycling and dormant cells in the progenitor pool, vinblastine was also administered under various schedules of treatment with respect to time and dosage to follow the changes induced by this drug in the irradiated recovering marrow. The depopulation of total bone-m arrow cells caused by vinblastine proceeded at a comparable rate in both the irradiated and the normal mouse. On the other hand, depopulation of the colony-formers is faster in animals irradiated 1 -2 days previously as compared with normal animals or mice irradiated 1 week or 2 weeks earlier. The data were interpreted to show that in the marrow of a newly-irradiated animal more cells are in a fast cycle than in a normal or a recovering animal. Data are finally presented and discussed concerning the use of vinblastine for studies of stem cell kinetics in haemopoietic tissues. (author)

  19. Characterization of xenogeneic mouse-to-rat bone marrow chimeras. I. Examination of hematologic and immunologic function

    International Nuclear Information System (INIS)

    Wade, A.C.; Luckert, P.H.; Tazume, S.; Niedbalski, J.L.; Pollard, M.

    1987-01-01

    Eighteen xenogeneic chimeric rats (survival: greater than 100 days) were established by transplanting bone marrow cells from femurs of 10 gnotobiotic CFW mice into each germfree Sprague-Dawley or Wistar rat. The erythrocytes circulating in the rats were of mouse origin as determined by hemagglutination. Hemoglobin electrophoresis, radial immunodiffusion for IgG, and assay of granulocytic neutrophils for leukocyte alkaline phosphatase verified that true chimerism was achieved. The extent of hematological and immunological reconstitution varied. In general, hematocrit levels were low to normal, white blood cell counts and differentials were within normal limits, and serum protein levels were normal. Levels of circulating IgG of each species were comparable to those of germfree rat and mouse controls. Natural killer (NK) activity was depressed, a phenomenon that may be attributable to the radiation treatment of recipients, or to failure to transfer NK cells or precursors. Mitogenic stimulation reactions were varied, but most chimeric rats demonstrated moderately depressed responses. Reactions as a whole suggested that gnotobiotic rats with xenogeneic bone marrow are incompletely reconstituted, both hematologically and immunologically. No acute graft-versus-host reaction was seen

  20. Quantum chimera states

    Energy Technology Data Exchange (ETDEWEB)

    Viennot, David, E-mail: david.viennot@utinam.cnrs.fr; Aubourg, Lucile

    2016-02-15

    We study a theoretical model of closed quasi-hermitian chain of spins which exhibits quantum analogues of chimera states, i.e. long life classical states for which a part of an oscillator chain presents an ordered dynamics whereas another part presents a disordered dynamics. For the quantum analogue, the chimera behaviour deals with the entanglement between the spins of the chain. We discuss the entanglement properties, quantum chaos, quantum disorder and semi-classical similarity of our quantum chimera system. The quantum chimera concept is novel and induces new perspectives concerning the entanglement of multipartite systems. - Highlights: • We propose a spin chain model with long range couplings having purely quantum states similar to the classical chimera states. • The quantum chimera states are characterized by the coexistence of strongly entangled and non-entangled spins in the same chain. • The quantum chimera states present some characteristics of quantum chaos.

  1. Quantum chimera states

    International Nuclear Information System (INIS)

    Viennot, David; Aubourg, Lucile

    2016-01-01

    We study a theoretical model of closed quasi-hermitian chain of spins which exhibits quantum analogues of chimera states, i.e. long life classical states for which a part of an oscillator chain presents an ordered dynamics whereas another part presents a disordered dynamics. For the quantum analogue, the chimera behaviour deals with the entanglement between the spins of the chain. We discuss the entanglement properties, quantum chaos, quantum disorder and semi-classical similarity of our quantum chimera system. The quantum chimera concept is novel and induces new perspectives concerning the entanglement of multipartite systems. - Highlights: • We propose a spin chain model with long range couplings having purely quantum states similar to the classical chimera states. • The quantum chimera states are characterized by the coexistence of strongly entangled and non-entangled spins in the same chain. • The quantum chimera states present some characteristics of quantum chaos.

  2. Influence of age, irradiation and humanization on NSG mouse phenotypes

    Directory of Open Access Journals (Sweden)

    Jaclyn S. Knibbe-Hollinger

    2015-10-01

    Full Text Available Humanized mice are frequently utilized in bench to bedside therapeutic tests to combat human infectious, cancerous and degenerative diseases. For the fields of hematology-oncology, regenerative medicine, and infectious diseases, the immune deficient mice have been used commonly in basic research efforts. Obstacles in true translational efforts abound, as the relationship between mouse and human cells in disease pathogenesis and therapeutic studies requires lengthy investigations. The interplay between human immunity and mouse biology proves ever more complicated when aging, irradiation, and human immune reconstitution are considered. All can affect a range of biochemical and behavioral functions. To such ends, we show age- and irradiation-dependent influences for the development of macrocytic hyper chromic anemia, myelodysplasia, blood protein reductions and body composition changes. Humanization contributes to hematologic abnormalities. Home cage behavior revealed day and dark cycle locomotion also influenced by human cell reconstitutions. Significant age-related day-to-day variability in movement, feeding and drinking behaviors were observed. We posit that this data serves to enable researchers to better design translational studies in this rapidly emerging field of mouse humanization.

  3. Smallest chimera states

    Science.gov (United States)

    Maistrenko, Yuri; Brezetsky, Serhiy; Jaros, Patrycja; Levchenko, Roman; Kapitaniak, Tomasz

    2017-01-01

    We demonstrate that chimera behavior can be observed in small networks consisting of three identical oscillators, with mutual all-to-all coupling. Three different types of chimeras, characterized by the coexistence of two coherent oscillators and one incoherent oscillator (i.e., rotating with another frequency) have been identified, where the oscillators show periodic (two types) and chaotic (one type) behaviors. Typical bifurcations at the transitions from full synchronization to chimera states and between different types of chimeras have been described. Parameter regions for the chimera states are obtained in the form of Arnold tongues, issued from a singular parameter point. Our analysis suggests that chimera states can be observed in small networks relevant to various real-world systems.

  4. The mathematics behind chimera states

    Science.gov (United States)

    Omel’chenko, O. E.

    2018-05-01

    Chimera states are self-organized spatiotemporal patterns of coexisting coherence and incoherence. We give an overview of the main mathematical methods used in studies of chimera states, focusing on chimera states in spatially extended coupled oscillator systems. We discuss the continuum limit approach to these states, Ott-Antonsen manifold reduction, finite size chimera states, control of chimera states and the influence of system design on the type of chimera state that is observed.

  5. Modulation of accelerated repopulation in mouse skin during daily irradiation

    International Nuclear Information System (INIS)

    Trott, K.-R.; Shirazi, A.; Heasman, F.

    1999-01-01

    Background and purpose: The timing of acceleration of repopulation in the epidermis during daily irradiation is related to the development of skin erythema and epidermal hypoplasia. Therefore, the relationship between impairment of the epidermal barrier function, the dermal inflammatory response and epidermal hypoplasia with the acceleration of repopulation was investigated.Materials and purpose: Skin fields of approximately 1 cm 2 on the thighs of TUC mice were given five daily fractions of 3 Gy in each week followed by top-up doses at the end of the first, the second, or the third week to determine residual epidermal tolerance and to calculate repopulation rates in weeks 1, 2, or 3. Systemic modulation of repopulation was attempted by daily indomethacine during fractionated irradiation whereas tape stripping or UV-B exposure before the start of fractionated irradiation attempted local modulation. In parallel experiments, the water permeability coefficient of the epidermis was determined ex vivo by studying transepidermal transport of tritiated water.Results: Without modulation, no repopulation was found in the first week of daily fractionation but repopulation compensated 30% of the dose given in week two and 70% of the dose given in week three. Only tape stripping before the start of fractionated irradiation accelerated repopulation in week one. UV-B had no effect on repopulation although it stimulated proliferation as much as tape stripping. Indomethacin did not suppress acceleration of repopulation. A significant increase in transepidermal water loss was found but only after repopulation had already accelerated.Conclusions: Acceleration of repopulation in mouse epidermis during daily-fractionated irradiation is not related to the simultaneous development of an inflammatory response. Also, the loss of the epidermal barrier function is not involved in the development of the acceleration response, which rather seems to be triggered directly by the decreased

  6. Histopathological changes in exocrine glands of murine transplantation chimeras. II: Sjögren's syndrome-like exocrinopathy in mice without lupus nephritis. A model of primary Sjögren's syndrome

    DEFF Research Database (Denmark)

    Ussing, Anne Phaff; Prause, J.U.; Sørensen, Inger

    1992-01-01

    Autoimmune disease, primary Sjögren's syndrome, transplantation chimeras, experimental model, exocrinopathy, inbred mouse strains......Autoimmune disease, primary Sjögren's syndrome, transplantation chimeras, experimental model, exocrinopathy, inbred mouse strains...

  7. Distinct fates of self-specific T cells developing in irradiation bone marrow chimeras: Clonal deletion, clonal anergy, or in vitro responsiveness to self-Mls-1a controlled by hemopoietic cells in the thymus

    International Nuclear Information System (INIS)

    Speiser, D.E.; Chvatchko, Y.; Zinkernagel, R.M.; MacDonald, H.R.

    1990-01-01

    Elimination of potentially self-reactive T lymphocytes during their maturation in the thymus has been shown to be a major mechanism in accomplishing self-tolerance. Previous reports demonstrated that clonal deletion of self-Mls-1a-specific V beta 6+ T lymphocyte is controlled by a radiosensitive I-E+ thymic component. Irradiation chimeras reconstituted with I-E- bone marrow showed substantial numbers of mature V beta 6+ T cells despite host Mls-1a expression. Analysis of the functional properties of such chimeric T cells revealed a surprising variability in their in vitro reactivity to host Mls-1a, depending on the H-2 haplotype of stem cells used for reconstitution. In chimeras reconstituted with B10.S (H-2s) stem cells, mature V beta 6+ lymphocytes were present but functionally anergic to host-type Mls-1a in vitro. In contrast, in chimeras reconstituted with B10.G (H-2q) bone marrow, nondeleted V beta 6+ cells were highly responsive to Mls-1a in vitro. These findings suggest that clonal anergy of V beta 6+ cells to self-Mls-1a may be controlled by the affinity/avidity of T cell receptor interactions with bone marrow-derived cells in the thymus depending on the major histocompatibility complex class II molecules involved. Furthermore, chimeras bearing host (Mls-1a)-reactive V beta 6+ cells did not differ clinically from those with anergic or deleted V beta 6+ cells and survived more than one year without signs of autoimmune disease. Interestingly, their spleen cells had no Mls-1a stimulatory capacity in vitro. Therefore, regulation at the level of antigen presentation may be an alternative mechanism for maintenance of tolerance to certain self-antigens such as Mls-1a

  8. Differential expression of growth factors in irradiated mouse testes

    International Nuclear Information System (INIS)

    Mauduit, Claire; Siah, Ahmed; Foch, Marie; Chapet, Olivier; Clippe, Sebastien; Gerard, Jean-Pierre; Benahmed, Mohamed

    2001-01-01

    Purpose: By using as an experimental model the male mouse gonad, which contains both radiosensitive (germ) and radioresistant (somatic) cells, we have studied the growth factor (and/or receptor) expression of transforming growth factor-β receptor (TGFβ RI), stem cell factor (SCF), c-kit, Fas-L, Fas, tumor necrosis factor receptor (TNF R55), and leukemia inhibiting factor receptor (LIF-R) after local irradiation. Methods and Materials: Adult male mice were locally irradiated on the testes. Induction of apoptosis in the different testicular cell types following X-ray radiation was identified by the TdT-mediated dUTP Nick End Labeling (TUNEL) approach. Growth factor expression was evidenced by semiquantitative RT-PCR and Western blot analyses. Results: Apoptosis, identified through the TUNEL approach, occurred in radiosensitive testicular (premeotic) germ cells with the following kinetics: the number of apoptotic cells increased after 24 h (p<0.001) and was maximal 48 h after a 2-Gy ionizing radiation (p<0.001). Apoptotic cells were no longer observed 72 h after a 2-Gy irradiation. The number of apoptotic cells increased with the dose of irradiation (1-4 Gy). In the seminiferous tubules, the growth factor expression in premeiotic radiosensitive germ cells was modulated by irradiation. Indeed Fas, c-kit, and LIF-R expression, which occurs in (radiosensitive) germ cells, decreased 24 h after a 2-Gy irradiation, and the maximal decrease was observed with a 4-Gy irradiation. The decrease in Stra8 expression occurred earlier, at 4 h after a 2-Gy irradiation. In addition, a significant (p<0.03) decrease in Stra8 mRNA levels was observed at the lowest dose used (0.5 Gy, 48 h). Moreover, concerning a growth factor receptor, such as TGFβ RI, which is expressed both in radiosensitive and radioresistant cells, we observed a differential expression depending on the cell radiosensitivity after irradiation. Indeed, TGFβ RI expression was increased after irradiation in

  9. Gargoyles, Grotesques, & Chimeras

    Science.gov (United States)

    Wilbert, Nancy Corrigan

    2010-01-01

    Gargoyles, grotesques, and chimeras are scary, mythical (and sometimes humorous) creatures that have functional, decorative, and spiritual significance in medieval architecture. In this article, the author describes how her ceramics students created contemporary versions of gargoyles, chimeras, and grotesque faces. (Contains 1 online resource.)

  10. Chimera states in bursting neurons

    OpenAIRE

    Bera, Bidesh K.; Ghosh, Dibakar; Lakshmanan, M.

    2015-01-01

    We study the existence of chimera states in pulse-coupled networks of bursting Hindmarsh-Rose neurons with nonlocal, global and local (nearest neighbor) couplings. Through a linear stability analysis, we discuss the behavior of stability function in the incoherent (i.e. disorder), coherent, chimera and multi-chimera states. Surprisingly, we find that chimera and multi-chimera states occur even using local nearest neighbor interaction in a network of identical bursting neurons alone. This is i...

  11. Effect of low-dose irradiation on pregnant mouse haemopoiesis

    International Nuclear Information System (INIS)

    Weinberg, S.R.; McCarthy, E.G.; MacVittie, T.J.; Baum, S.J.

    1981-01-01

    The effects of low-dose gamma radiation to haemopoietic progenitor cell compartments of the marrow and spleen of virgin female mice and pregnant mice were studied. Microplasma clot cultures were used to assess burst-forming uniterythroid (BFU-E) and colony-forming unit-erythroid (CFU-E) activity, and double-layer agar cultures were established to evaluate granulocyte-macrophage colony-forming cell (GM-CFC) and macrophage colony-forming cell (M-CFC). The apparent shift in maternal erythropoiesis from the bone marrow to the enlarged spleen was reflected by an increase in CFU-E and BFU-E per spleen and a concomitant decrease in CFU-E and BFU-E per femur. Whereas maternal GM-CFC values per femur increased 36%, maternal GM-CFC per spleen increased by 172% compared to virgin values. Total-body irradiation to the day-10.5 pregnant mouse caused a further suppression of day-14.5 medullary erythropoiesis (i.e. decreased CFU-E values) compared to the virgin female mouse. An ability of the maternal spleen to support further compensatory erythropoiesis following increasing doses of radiation was demonstrated. Four days after 1.0 Gy exposure, maternal values for GM-CFC per femur or spleen decreased to nonirradiated virgin mice values. M-CFC per maternal femur decreased to nonirradiated virgin mice values. M-CFC per maternal femur decreased following 1.5 Gy, but M-CFC per spleen appeared to be unaffected with doses from 0.5 to 2.0 Gy. (author)

  12. Quality assurance of {sup 137}Cs Photons for Vivo Mouse Irradiation System

    Energy Technology Data Exchange (ETDEWEB)

    Noh, S. J. [Inje Univ., Kimhae (Korea, Republic of); Kim, H. J.; Jeong, D. H.; Yang, K. M.; Son, T. G.; Kang, Y. R. [Dongnam Institute of Radiological and Medical Sciences, Busan (Korea, Republic of); Shin, S. G.; Kye, Y. U. [Pohang University of Science and Technology, Pohang (Korea, Republic of)

    2014-10-15

    The multi-purpose irradiation apparatus using a {sup 137}Cs, which can be used for the blood test, can be affected by the other components of the experiments such as the size and shape of the beaker and the maximum variation of more than 35% has been reported. The mount of the absorbed dose is determined by the distance between irradiation target and the source and the irradiation time with the irradiator (Gamma Irradiator, Chiyoda Technol Co, Japan) for this experiment. The low-dose irradiation has been used in this study is advantageous for irradiating the cell culture vessel or the small animal. However, radiation is performed by placing the 3-5 mice in each mouse cage (polycarbonate cage). In this case, overlapping often happens to the target during irradiation. Irradiating without considering the geometrical aspect of the irradiation device can occur as well. To solve the problems, the mouse apartment with the 45 mouse cages is built and the device is assessed by being compared with the conventional method in 2 different ways. Firstly, the glass dosimeters were inserted into the head and the body of the lab mice for 2 methods. Secondly, MCNP simulation was performed for absorbed dose and air kerma measurements in each mouse apartment chamber. In this study, the system that allows the accurate irradiation using the {sup 137}Cs gamma irradiator mainly used in Radiation Biology was developed and the accuracy of the system has been confirmed by the experiments. The dose delivery using the conventional system had the variation of 42% at most whereas the variation was less than 6% for the mouse apartment. From the MCNP simulation, the difference between each chamber was less than 0.1% and 0.4% for the air kerma and the absorbed dose respectively. Considering the statistical error of MCNP and the assumption from the simulation, the accuracy of the simulation was matched well with the measurements with the glass dosimeters.

  13. Quality assurance of 137Cs Photons for Vivo Mouse Irradiation System

    International Nuclear Information System (INIS)

    Noh, S. J.; Kim, H. J.; Jeong, D. H.; Yang, K. M.; Son, T. G.; Kang, Y. R.; Shin, S. G.; Kye, Y. U.

    2014-01-01

    The multi-purpose irradiation apparatus using a 137 Cs, which can be used for the blood test, can be affected by the other components of the experiments such as the size and shape of the beaker and the maximum variation of more than 35% has been reported. The mount of the absorbed dose is determined by the distance between irradiation target and the source and the irradiation time with the irradiator (Gamma Irradiator, Chiyoda Technol Co, Japan) for this experiment. The low-dose irradiation has been used in this study is advantageous for irradiating the cell culture vessel or the small animal. However, radiation is performed by placing the 3-5 mice in each mouse cage (polycarbonate cage). In this case, overlapping often happens to the target during irradiation. Irradiating without considering the geometrical aspect of the irradiation device can occur as well. To solve the problems, the mouse apartment with the 45 mouse cages is built and the device is assessed by being compared with the conventional method in 2 different ways. Firstly, the glass dosimeters were inserted into the head and the body of the lab mice for 2 methods. Secondly, MCNP simulation was performed for absorbed dose and air kerma measurements in each mouse apartment chamber. In this study, the system that allows the accurate irradiation using the 137 Cs gamma irradiator mainly used in Radiation Biology was developed and the accuracy of the system has been confirmed by the experiments. The dose delivery using the conventional system had the variation of 42% at most whereas the variation was less than 6% for the mouse apartment. From the MCNP simulation, the difference between each chamber was less than 0.1% and 0.4% for the air kerma and the absorbed dose respectively. Considering the statistical error of MCNP and the assumption from the simulation, the accuracy of the simulation was matched well with the measurements with the glass dosimeters

  14. Study on changes of sperm count and testis tissue in black mouse after neutron irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Chun, Ki Jung; Seo, Won Sook [KAERI, Daejeon (Korea, Republic of); Son, Hwa Young [Chungnam National Univ., Daejeon (Korea, Republic of)

    2006-03-15

    For the purpose of the biological effect in black mouse by neutron irradiation, mice were irradiated with 16 or 32 Gy neutron (flux: 1.036739E+09) by lying flat pose at BNCT facility on HANARO Reactors. And 90 days later of irradiation, physical changes of testis and testis tissue were examined. There were no weight changes but a little bit volume changes and sperm counts in the tests. Atrophy of seminiferous tubules irradiated with 32 Gy neutron is increased in number and severity and those in stage VI showed depletion of spermatogonia and pachytene spermatocytes compared to the non-irradiated control group. Testis damage of black mouse was not recovered after long time by 32 Gy neutron irradiation.

  15. Study on changes of sperm count and testis tissue in black mouse after neutron irradiation

    International Nuclear Information System (INIS)

    Chun, Ki Jung; Seo, Won Sook; Son, Hwa Young

    2006-01-01

    For the purpose of the biological effect in black mouse by neutron irradiation, mice were irradiated with 16 or 32 Gy neutron (flux: 1.036739E+09) by lying flat pose at BNCT facility on HANARO Reactors. And 90 days later of irradiation, physical changes of testis and testis tissue were examined. There were no weight changes but a little bit volume changes and sperm counts in the tests. Atrophy of seminiferous tubules irradiated with 32 Gy neutron is increased in number and severity and those in stage VI showed depletion of spermatogonia and pachytene spermatocytes compared to the non-irradiated control group. Testis damage of black mouse was not recovered after long time by 32 Gy neutron irradiation

  16. Residual activation events functional after irradiation of mouse splenic lymphocytes

    International Nuclear Information System (INIS)

    Duncan, D.D.; Lawrence, D.A.

    1991-01-01

    We have sought to identify the radiosensitivity of lymphocytes by determining the extent of activation of mitogen-stimulated lymphocytes previously exposed to growth-inhibiting doses of radiation. Mouse splenic lymphocytes were exposed to 0-15 Gy 137Cs radiation, and structural and functional damage were assayed. Although damage to cellular thiols and nonprotein thiols was modest, there was a significant loss of viability by 6 h as determined by uptake of propidium iodide (PI). Since cells did not die immediately after irradiation, the activation events which remained were evaluated. Growth-inhibiting doses of radiation left cells partially responsive to mitogen, in that cells were able to exit G0 phase, but they could progress no further into the cell cycle than G1a phase. It is important to note that assessment of viability by uptake of PI indicated substantial cell death after 15 Gy (45%, 6 h; 90%, 24 h); however, cell cycle analysis at 24 h indicated no significant decrease in progression from G0 to G1a phase. The LPS-stimulated response of B cells was more radiosensitive than the Con A-stimulated response of T cells. Further analysis of the Con A response indicated that production of interleukin-2 (IL-2) was unaffected, but expression of the IL-2 receptor was inhibited. Inhibition of poly-ADP-ribosylation and damage to lipids did not prevent the lack of mitogen responsiveness, since neither the ADP-ribose transferase inhibitor 3-aminobenzamide nor lipid radical scavengers had restorative effects on the mitogenic response. Nor was Con A-stimulated incorporation of [3H]thymidine restored with inhibitors of prostaglandin or leukotriene synthesis, suggesting that inhibition was due to direct effects on the Con A responders, and not indirect effects mediated by arachidonate metabolites

  17. Mouse skin damages caused by fractionated irradiation with carbon ions

    Energy Technology Data Exchange (ETDEWEB)

    Ando, K; Chen, Y J; Ohira, C; Nojima, K; Ando, S; Kobayashi, N; Ohbuchi, T; Shimizu, W [Space and Particle Radiation Science Research Group, Chiba (Japan); Koike, S; Kanai, T [National Inst. of Radiological Sciences, Chiba (Japan). Div. of Accelerator Physics

    1997-09-01

    We have investigated carbon-dose responses of early and late skin damages after daily fractionations to the mouse leg. Depilated legs were irradiated with 7 different positions within 290 MeV/u carbon beams. Fractionation schedules were 1, 2, 4 and 8 daily fractions. Skin reaction was scored every other day for 32 days. Five highest scores in individual mice were averaged, and used as averaged peak reaction. The isoeffect doses to produce an averaged peak skin reaction of 3.0 (moist desquamation) on dose-response curves were calculated with 95% confidence limit. The isoeffect dose for control gamma rays constantly increased with an increase in the number of fraction. The isoeffect doses in low LET carbon ions of 14- and 20 keV/{mu}m also increased up to 4 fractions, but did not increase when 4 fractions increased to 8 fractions. The saturation of isoeffect dose was more prominently observed for 40 keV/{mu}m in such that the isoeffect doses did not change among 2, 4 and 8 fractions. The isoeffect doses for LET higher than 50 keV/{mu}m were smaller than those for lower LET. However, the isoeffect doses for 50-, 60-, 80- and 100 keV/{mu} steadily increased with an increase in the number of fraction and did not show any saturation up to 8 fractions. Relation between LET and RBE was linear for all fractionation schedules. The slope of regression line in 4 fractions was steepest, and significantly (P<0.05) different from that in 1 fraction. (orig.)

  18. Mouse skin damages caused by fractionated irradiation with carbon ions

    International Nuclear Information System (INIS)

    Ando, K.; Chen, Y.J.; Ohira, C.; Nojima, K.; Ando, S.; Kobayashi, N.; Ohbuchi, T.; Shimizu, W.; Koike, S.; Kanai, T.

    1997-01-01

    We have investigated carbon-dose responses of early and late skin damages after daily fractionations to the mouse leg. Depilated legs were irradiated with 7 different positions within 290 MeV/u carbon beams. Fractionation schedules were 1, 2, 4 and 8 daily fractions. Skin reaction was scored every other day for 32 days. Five highest scores in individual mice were averaged, and used as averaged peak reaction. The isoeffect doses to produce an averaged peak skin reaction of 3.0 (moist desquamation) on dose-response curves were calculated with 95% confidence limit. The isoeffect dose for control gamma rays constantly increased with an increase in the number of fraction. The isoeffect doses in low LET carbon ions of 14- and 20 keV/μm also increased up to 4 fractions, but did not increase when 4 fractions increased to 8 fractions. The saturation of isoeffect dose was more prominently observed for 40 keV/μm in such that the isoeffect doses did not change among 2, 4 and 8 fractions. The isoeffect doses for LET higher than 50 keV/μm were smaller than those for lower LET. However, the isoeffect doses for 50-, 60-, 80- and 100 keV/μ steadily increased with an increase in the number of fraction and did not show any saturation up to 8 fractions. Relation between LET and RBE was linear for all fractionation schedules. The slope of regression line in 4 fractions was steepest, and significantly (P<0.05) different from that in 1 fraction. (orig.)

  19. The response of previously irradiated mouse skin to heat alone or combined with irradiation: influence of thermotolerance

    International Nuclear Information System (INIS)

    Wondergem, J.; Haveman, J.

    1983-01-01

    The effect of previous x-irradiation on the response to hyperthermia (44 0 C), x-irradiation, and irradiation combined with hyperthermia (43 0 C or 44 0 C) was studied in mouse foot skin. Irradiation of mice feet 90 days before, with 20 Gy, increased the subsequent response to heat alone, or combined with irradiation, as well as to irradiation alone. It had little effect on the thermal enhancement ratios for both acute and late skin reactions. Memory of the previous irradiation treatment could be masked when the temperature of the subsequent heat treatment alone, or combined with irradiation, was 44 0 C. Priming heat treatment induced resistance to a subsequent heat treatment and to a subsequent combined irradiation-heat treatment in normal as well as previously irradiated skin. When late skin reaction was considered, a larger 'memory' of the previous irradiation treatment was always evident, compared to acute skin reaction: the 'remembered' dose in the late skin reaction was about twice the 'remembered' dose in the acute reaction. (U.K.)

  20. Radioprotection by dipyridamole in the aging mouse. Effects on lipid peroxidation in mouse liver, spleen and brain after whole-body X-ray irradiation

    International Nuclear Information System (INIS)

    Seino, Noritaka

    1995-01-01

    To investigate the radioprotective effect of dipyridamole in the aging mouse, the lipid peroxide content in aging mouse liver, spleen and brain irradiated by X-ray were measured both before and after injection of dipyridamole. The lipid peroxide content increased with aging from 2 months old to 16 months old in the mouse liver, spleen and brain. The content of lipid peroxide in the liver and spleen of the aging mouse was significantly increased in 7 days after whole-body irradiation with 8 Gy, but was unchanged in the brain. Dipyridamole, given before irradiation, significantly inhibited the increase of lipid peroxide after irradiation. These results suggest that dipyridamole may have radioprotective effects on aging mouse liver and spleen as well as on young mouse, and that inhibition of lipid peroxidation is a possible factor in the radioprotective effect of dipyridamole. (author)

  1. Amplitude chimeras and chimera death in dynamical networks

    International Nuclear Information System (INIS)

    Zakharova, Anna; Kapeller, Marie; Schöll, Eckehard

    2016-01-01

    We find chimera states with respect to amplitude dynamics in a network of Stuart- Landau oscillators. These partially coherent and partially incoherent spatio-temporal patterns appear due to the interplay of nonlocal network topology and symmetry-breaking coupling. As the coupling range is increased, the oscillations are quenched, amplitude chimeras disappear and the network enters a symmetry-breaking stationary state. This particular regime is a novel pattern which we call chimera death. It is characterized by the coexistence of spatially coherent and incoherent inhomogeneous steady states and therefore combines the features of chimera state and oscillation death. Additionally, we show two different transition scenarios from amplitude chimera to chimera death. Moreover, for amplitude chimeras we uncover the mechanism of transition towards in-phase synchronized regime and discuss the role of initial conditions. (paper)

  2. Symmetries of Chimera States

    Science.gov (United States)

    Kemeth, Felix P.; Haugland, Sindre W.; Krischer, Katharina

    2018-05-01

    Symmetry broken states arise naturally in oscillatory networks. In this Letter, we investigate chaotic attractors in an ensemble of four mean-coupled Stuart-Landau oscillators with two oscillators being synchronized. We report that these states with partially broken symmetry, so-called chimera states, have different setwise symmetries in the incoherent oscillators, and in particular, some are and some are not invariant under a permutation symmetry on average. This allows for a classification of different chimera states in small networks. We conclude our report with a discussion of related states in spatially extended systems, which seem to inherit the symmetry properties of their counterparts in small networks.

  3. Radiobiological researches on Dianthus caryophyllus L. carnation chimeras

    International Nuclear Information System (INIS)

    Pereau-Leroy, Pierre

    1975-01-01

    This research thesis reports a radiobiological study of Dianthus periclinal chimeras performed by submitting plants and plant cuttings at different physiological stages to cobalt-60 gamma irradiation under different dose conditions and rates. The effects of these treatments are studied while growing the so-processed plants and by microscopic examination of sections of irradiated meristems [fr

  4. T lymphocytes from irradiation chimeras repopulated with 13-day fetal liver cells recognize antigens only in association with self-MHC products

    International Nuclear Information System (INIS)

    Nisbet-Brown, E.; Diener, E.

    1986-01-01

    The restriction specificities of maturing thymocytes are determined by the Class II MHC antigens expressed by non-lymphoid thymic tissues. The proliferative response of mature T lymphocytes to antigen-presenting cells (APC) and antigen requires that the APC express the same MHC antigens as the thymus in which the T cells differentiated. Thus, in the two-way bone marrow chimera [A + B----(A x B)F1], T lymphocyte populations of A and B haplotypes have each acquired the potential to recognize antigens associated with either parental haplotype. In spite of the large body of work on MHC restriction, we still do not have a clear understanding of the mechanisms which impose self restriction. The chimeric model systems used previously to study MHC restriction have used adult bone marrow cells as the source of lymphoid precursors. During normal ontogeny, T cells are derived from precursors in the fetal liver and we felt that a direct comparison of T cells from fetal liver and bone marrow-repopulated animals would shed light on the development of MHC restriction specificities during T cell ontogeny in the thymus or prethymically. We found that parental T lymphocyte populations isolated from two-way fetal liver chimeras cooperated only with syngeneic APC, while those from bone marrow chimeras cooperated with APC of either parental haplotype. This suggests that fetal liver and bone marrow may not be equivalent sources of stem cells. Our results may be due to fundamental differences between thymocyte precursors in fetal liver and bone marrow, including the time course of their expression of T cell receptor gene products

  5. Suppression of mouse-killing in rats following irradiation

    International Nuclear Information System (INIS)

    O'Boyle, M.

    1976-01-01

    Suppression of mouse-killing was produced following pairings of mouse-presentations (CS) with 96 roentgens of ionizing radiation (US) at 0 (less than 2 min.) and 30 min. US-CS interstimulus intervals. No suppression was found at CS-US intervals of 30 min., 1 hr., and 2 hr., or at US-CS intervals of 1 hr. and 2 hr

  6. Chimera: Experiencing Language Arts.

    Science.gov (United States)

    Paul, Rebecca K.

    1991-01-01

    Describes the production of a dramatic musical, Chimera: A Journey to Redoubtia, at Chapman Elementary School in Anchor Point, Alaska. Student participation in the project, and students' rewards from participation, are detailed. Benefits of the integration of dramatics into the language arts curriculum are listed. (BB)

  7. Interferon synthesis in mouse peritoneal cells damaged by x irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Szolgay, E; T' alas, M

    1976-01-01

    NDV-induced interferon of peritoneal cells of irradiated (x-rays, 400 R) and control mice was investigated in vitro. Irradiation or treatment with hydroxyurea (10(-5) M) and mitomycin C (25 microng/ml) did not change interferon synthesis in spite of an 80 to 90% inhibition of 3H-thymidine incorporation. Increased doses of mitomycin C and treatment with actinomycin D and puromycin blocked interferon production. De novo interferon synthesis occurred in cells with damaged replicative activity of DNA caused by irradiation or by treatment with antimetabolites.

  8. Chromosomal integrity of freeze-dried mouse spermatozoa after 137Cs γ-ray irradiation

    International Nuclear Information System (INIS)

    Kusakabe, Hirokazu; Kamiguchi, Yujiroh

    2004-01-01

    This study demonstrated that freeze-dried mouse spermatozoa possess strong resistance to 137 Cs γ-ray irradiation at doses of up to 8 Gy. Freeze-dried mouse spermatozoa were rehydrated and injected into mouse oocytes with an intracytoplasmic sperm injection (ICSI) technique. Most oocytes can be activated after ICSI by using spermatozoa irradiated with γ-rays before and after freeze-drying. Sperm chromosome complements were analyzed at the first cleavage metaphase. Chromosome aberrations increased in a dose-dependent manner in the spermatozoa irradiated before freeze-drying. However, no increase in oocytes with chromosome aberrations was observed when fertilized by spermatozoa that had been irradiated after freeze-drying, as compared with freeze-dried spermatozoa that had not been irradiated. These results suggest that both the chromosomal integrity of freeze-dried spermatozoa, as well as their ability to activate oocytes, were protected from γ-ray irradiation at doses at which chromosomal damage is found to be strongly induced in spermatozoa suspended in solution

  9. Localized irradiation of mouse legs using an image-guided robotic linear accelerator.

    Science.gov (United States)

    Kufeld, Markus; Escobar, Helena; Marg, Andreas; Pasemann, Diana; Budach, Volker; Spuler, Simone

    2017-04-01

    To investigate the potential of human satellite cells in muscle regeneration small animal models are useful to evaluate muscle regeneration. To suppress the inherent regeneration ability of the tibialis muscle of mice before transplantation of human muscle fibers, a localized irradiation of the mouse leg should be conducted. We analyzed the feasibility of an image-guided robotic irradiation procedure, a routine treatment method in radiation oncology, for the focal irradiation of mouse legs. After conducting a planning computed tomography (CT) scan of one mouse in its customized mold a three-dimensional dose plan was calculated using a dedicated planning workstation. 18 Gy have been applied to the right anterior tibial muscle of 4 healthy and 12 mice with immune defect in general anesthesia using an image-guided robotic linear accelerator (LINAC). The mice were fixed in a customized acrylic mold with attached fiducial markers for image guided tracking. All 16 mice could be irradiated as prevised without signs of acute radiation toxicity or anesthesiological side effects. The animals survived until scarification after 8, 21 and 49 days as planned. The procedure was straight forward and the irradiation process took 5 minutes to apply the dose of 18 Gy. Localized irradiation of mice legs using a robotic LINAC could be conducted as planned. It is a feasible procedure without recognizable side effects. Image guidance offers precise dose delivery and preserves adjacent body parts and tissues.

  10. Chimera Grid Tools

    Science.gov (United States)

    Chan, William M.; Rogers, Stuart E.; Nash, Steven M.; Buning, Pieter G.; Meakin, Robert

    2005-01-01

    Chimera Grid Tools (CGT) is a software package for performing computational fluid dynamics (CFD) analysis utilizing the Chimera-overset-grid method. For modeling flows with viscosity about geometrically complex bodies in relative motion, the Chimera-overset-grid method is among the most computationally cost-effective methods for obtaining accurate aerodynamic results. CGT contains a large collection of tools for generating overset grids, preparing inputs for computer programs that solve equations of flow on the grids, and post-processing of flow-solution data. The tools in CGT include grid editing tools, surface-grid-generation tools, volume-grid-generation tools, utility scripts, configuration scripts, and tools for post-processing (including generation of animated images of flows and calculating forces and moments exerted on affected bodies). One of the tools, denoted OVERGRID, is a graphical user interface (GUI) that serves to visualize the grids and flow solutions and provides central access to many other tools. The GUI facilitates the generation of grids for a new flow-field configuration. Scripts that follow the grid generation process can then be constructed to mostly automate grid generation for similar configurations. CGT is designed for use in conjunction with a computer-aided-design program that provides the geometry description of the bodies, and a flow-solver program.

  11. Differential effects of fractionated X irradiation on mouse spermatogonial stem cells

    NARCIS (Netherlands)

    van der Meer, Y.; Huiskamp, R.; Davids, J. A.; de rooij, D. G.

    1993-01-01

    The response of spermatogonial stem cells to fractionated X irradiation was studied in the various stages of the spermatogenic cycle of the CBA mouse. Fractionated doses of 2 + 2, 1 + 3, and 3 + 1 Gy with a 24-h interval between the doses were compared with a single dose of 4 Gy. The numbers of

  12. SU-F-T-668: Irradiating Mouse Brain with a Clinical Linear Accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Perez-Torres, C [N Rancilio Purdue University, West Lafayette, IN (United States)

    2016-06-15

    Purpose: To design and construct a “mouse jig” device that would allow for irradiation of the mouse brain with a clinical Varian 6 MeV Linear Accelerator. This device must serve as a head immobilizer, gaseous anesthesia delivery, and radiation bolus concurrently. Methods: The mouse jig was machined out of nylon given that it is inexpensive, easy to machine, and has similar electron density to water. A cylindrical opening with diameter of 16 mm and 40 mm depth was drilled into a nylon block sized 56×56×50 mm (width, length, depth). Additional slots were included in the block for ear bars and a tooth bar to serve as a three-point immobilization device as well as for anesthesia delivery and scavenging. For ease of access when loading the mouse into the holder, there is a removable piece at the top of the block that is 15 mm in depth. This serves a dual purpose, as with the proper extra shielding, the mouse jig could be used with lower linear energy transfer photons with this piece removed. A baseplate was then constructed with five square slots where the mouse jig can securely be inserted plus additional slots that would allow the baseplate to be mounted on a standard lock bar in the treatment couch. This maximizes the reproducibility of placement between imaging and treatment and between treatment sessions. Results: CT imaging and radiation treatment planning was performed that showed acceptable coverage and uniformity of radiation dose in the mouse brain while sparing the throat and eyes. Conclusion: We have designed and manufactured a device that fulfills our criteria allowing us to selectively irradiate the mouse brain with a clinical linear accelerator. This setup will be used for generating mouse models of radiation-induced brain injury.

  13. Interspecific in vitro assay for the chimera-forming ability of human pluripotent stem cells.

    Science.gov (United States)

    Masaki, Hideki; Kato-Itoh, Megumi; Umino, Ayumi; Sato, Hideyuki; Hamanaka, Sanae; Kobayashi, Toshihiro; Yamaguchi, Tomoyuki; Nishimura, Ken; Ohtaka, Manami; Nakanishi, Mahito; Nakauchi, Hiromitsu

    2015-09-15

    Functional assay limitations are an emerging issue in characterizing human pluripotent stem cells (PSCs). With rodent PSCs, chimera formation using pre-implantation embryos is the gold-standard assay of pluripotency (competence of progeny to differentiate into all three germ layers). In human PSCs (hPSCs), however, this can only be monitored via teratoma formation or in vitro differentiation, as ethical concerns preclude generation of human-human or human-animal chimeras. To circumvent this issue, we developed a functional assay utilizing interspecific blastocyst injection and in vitro culture (interspecies in vitro chimera assay) that enables the development and observation of embryos up to headfold stage. The assay uses mouse pre-implantation embryos and rat, monkey and human PSCs to create interspecies chimeras cultured in vitro to the early egg-cylinder stage. Intra- and interspecific chimera assays with rodent PSC lines were performed to confirm the consistency of results in vitro and in vivo. The behavior of chimeras developed in vitro appeared to recapitulate that of chimeras developed in vivo; that is, PSC-derived cells survived and were integrated into the epiblast of egg-cylinder-stage embryos. This indicates that the interspecific in vitro chimera assay is useful in evaluating the chimera-forming ability of rodent PSCs. However, when human induced PSCs (both conventional and naïve-like types) were injected into mouse embryos and cultured, some human cells survived but were segregated; unlike epiblast-stage rodent PSCs, they never integrated into the epiblast of egg-cylinder-stage embryos. These data suggest that the mouse-human interspecies in vitro chimera assay does not accurately reflect the early developmental potential/process of hPSCs. The use of evolutionarily more closely related species as host embryos might be necessary to evaluate the developmental potency of hPSCs. © 2015. Published by The Company of Biologists Ltd.

  14. Radiosensitive target in the early mouse embryo exposed to very low doses of ionizing radiation

    International Nuclear Information System (INIS)

    Wiley, Lynn M.; Raabe, Otto G.; Khan, Rakhshi; Straume, Tore

    1994-01-01

    We exposed mouse preimplantation embryos in vitro to either tritiated water (HTO) or tritiated thymidine (TdR) to determine whether the radiosensitive target was nuclear or extranuclear for embryonic cell proliferation disadvantage in the mouse embryo chimera assay. 8-cell embryos were incubated in either HTO or TdR for 2 h and paired with non-irradiated control embryos to form chimeras. Chimeras were cultured for an average of 20.2 h to allow for 2-3 cell cycles and then partially dissociated to obtain the number of progeny cells contributed by the two partner embryos for each chimera. These values were expressed as a 'proliferation ratio' (number of cells from the irradiated embryo: total number of cells in the chimera). A ratio significantly less than 0.50 indicates that the experimental embryo expressed an embryonic cell proliferation disadvantage, which is the endpoint of this assay. The activity concentrations of HTO and TdR were adjusted so that both would deliver comparable mean absorbed nuclear doses during the combined initial 2-h irradiation incubation and subsequent 20.2 h chimera incubation periods. Although nuclear doses were comparable under these conditions, the extranuclear dose delivered by the uniformly distributed HTO was about 100 times greater than the extranuclear dose delivered by TdR for each given nuclear dose. Consequently, obtaining mean TdR proliferation ratios≤mean HTO proliferation ratios would be evidence for a nuclear target while obtaining mean HTO proliferation ratios< mean TdR proliferation ratios would be evidence for an extranuclear target. TdR consistently produced lower mean proliferation ratios over a range of doses from 0.14 Gy to 0.43 Gy. Therefore, we conclude that the radiosensitive target for this endpoint is nuclear

  15. Cell and tissue kinetics of the subependymal layer in mouse brain following heavy charged particle irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Manley, N.B.; Fabrikant, J.I.; Alpen, E.L.

    1988-12-01

    The following studies investigate the cellular response and cell population kinetics of the subependymal layer in the mouse brain exposed to heavy charged particle irradiation. Partial brain irradiation with helium and neon ions was confined to one cortex of the brain. Both the irradiated and the unirradiated contralateral cortex showed similar disturbances of the cell and tissue kinetics in the subependymal layers. The irradiated hemisphere exhibited histological damage, whereas the unirradiated side appeared normal histologically. This study concerns the cell population and cell cycle kinetics of the subependymal layer in the mouse brain, and the effects of charged particle irradiations on this cell population. Quantitative high resolution autoradiography was used to study the kinetic parameters in this cell layer. This study should help in understanding the effects of these high-energy heavy ions on normal mammalian brain tissue. The response of the mammalian brain exposure to charged particle ionizing radiation may be extremely variable. It varies from minimal physiological changes to overt tissue necrosis depending on a number of factors such as: the administered dose, dose-rate, the volume of the irradiated tissue, and the biological end-point being examined.

  16. Immune tolerance in radiation chimeras

    International Nuclear Information System (INIS)

    Awaya, Kazuhiko; Kuniki, Hiromichi; Neki, Miyuki

    1978-01-01

    Establishment of immune tolerance in radiation chimeras and the mechanism of maintaining it were discussed from certain points. Semiallogeneic radiation chimeras are mostly of long-living, and the hematopoietic organ of this individual consists mainly of the cells derived from the marrow donor, i. e., F 1 -type cells. F 1 -type lymphocytes can distinguish parental strain cells from themselves. In these chimeras, a F 1 -skin graft maintains to be fresh as long as the host is alive, showing immune tolerance effective through its life. In establishment and maintenance of this immune tolerance, the suppressing mechanism of host-type or F 1 -type seems to be involved. The allogeneic radiation chimera has very poor long-survival rate compared with that of the semiallogeneic radiation chimera. To raise this survival rate, efforts are now being made from the immunological point of view. (Ueda, J.)

  17. Collagen synthesis in CBA mouse heart after total thoracic irradiation

    International Nuclear Information System (INIS)

    Murray, J.C.; Parkins, C.S.; Institute of Cancer Research, Sutton

    1988-01-01

    CBA mice were irradiated to the whole thorax with single doses of 240 kVp X-rays in the dose range 8-16 Gy. Collagen and total protein synthesis rates in the heart were measured at 2-monthly intervals using a radio-isotope incorporation techniques. Doses of 10 Gy or greater caused a slight increase in collagen synthesis, followed by significantly reduced collagen synthesis by 16 weeks or longer after treatment. The depression in synthesis appeared correspondingly earlier with increasing dose. Total protein synthesis in heart followed similar patterns although changes were not statistically significant, indicating that the changes reflected alterations to collagen synthesis specifally, and not protein synthesis in geneal. Total hydroxyproline measurements showed no significant changes in heart collagen at any time as a result of X-irradiation. 18 refs.; 7 figs

  18. Radiosensitivity and chimera formation in Hibiscus syriacus

    International Nuclear Information System (INIS)

    Kwon, S.H.; Won, J.L.

    1980-01-01

    Radiosensitivity of gamma-irradiated Hibiscus syriacus and chimera formation were investigated. The lethal dose-50 percent with respect to seeding and cuttings was 15kR and 2 approximately 3 kR respectively, chlorophyll mutation rate of seeds irradiated with 15 kR being about 13 percent. The degree of chimeric leaf mutants from the buds by radiation treatment depends on the bud position of the branch. Buds of the middle part of V 1 branch seemed to be more multi-cellular condition than the upper and low part when irradiation was made. It is assumed that at least two primordia of V 2 branch were already differentiated from the V 1 branch in Hibiscus syriacus plant. (Author)

  19. Recurrence quantification analysis of chimera states

    International Nuclear Information System (INIS)

    Santos, M.S.; Szezech, J.D.; Batista, A.M.; Caldas, I.L.; Viana, R.L.; Lopes, S.R.

    2015-01-01

    Chimera states, characterised by coexistence of coherence and incoherence in coupled dynamical systems, have been found in various physical systems, such as mechanical oscillator networks and Josephson-junction arrays. We used recurrence plots to provide graphical representations of recurrent patterns and identify chimera states. Moreover, we show that recurrence plots can be used as a diagnostic of chimera states and also to identify the chimera collapse. - Highlights: • Chimera states have been found in various physical systems. • Recurrence plots is a graphical method useful to locate recurring patterns. • We used recurrence plots to identify the chimera states. • We show also the recurrence plots can identify the chimera collapse

  20. Recurrence quantification analysis of chimera states

    Energy Technology Data Exchange (ETDEWEB)

    Santos, M.S. [Pós-Graduação em Ciências/Física, Universidade Estadual de Ponta Grossa, 84030-900, Ponta Grossa, PR (Brazil); Szezech, J.D., E-mail: jdanilo@gmail.com [Departamento de Matemática e Estatística, Universidade Estadual de Ponta Grossa, 84030-900, Ponta Grossa, PR (Brazil); Batista, A.M., E-mail: antoniomarcosbatista@gmail.com [Departamento de Matemática e Estatística, Universidade Estadual de Ponta Grossa, 84030-900, Ponta Grossa, PR (Brazil); Caldas, I.L. [Instituto de Física, Universidade de São Paulo, 05315-970, São Paulo, SP (Brazil); Viana, R.L.; Lopes, S.R. [Departamento de Física, Universidade Federal do Paraná, 81531-990, Curitiba, PR (Brazil)

    2015-10-02

    Chimera states, characterised by coexistence of coherence and incoherence in coupled dynamical systems, have been found in various physical systems, such as mechanical oscillator networks and Josephson-junction arrays. We used recurrence plots to provide graphical representations of recurrent patterns and identify chimera states. Moreover, we show that recurrence plots can be used as a diagnostic of chimera states and also to identify the chimera collapse. - Highlights: • Chimera states have been found in various physical systems. • Recurrence plots is a graphical method useful to locate recurring patterns. • We used recurrence plots to identify the chimera states. • We show also the recurrence plots can identify the chimera collapse.

  1. Curcumin Stimulates the Antioxidant Mechanisms in Mouse Skin Exposed to Fractionated γ-Irradiation

    Directory of Open Access Journals (Sweden)

    Ganesh Chandra Jagetia

    2015-01-01

    Full Text Available Fractionated irradiation is one of the important radiotherapy regimens to treat different types of neoplasia. Despite of the immense therapeutic gains accrued by delivering fractionated irradiation to tumors, the radiation burden on skin increases significantly. Low doses of irradiation to skin adversely affect its molecular and metabolic status. The use of antioxidant/s may help to alleviate the radiation-induced changes in the skin and allow delivering a higher dose of radiation to attain better therapeutic gains. Curcumin is an antioxidant and a free radical scavenging dietary supplement, commonly used as a flavoring agent in curries. Therefore, the effect of 100 mg/kg body weight curcumin was studied on the antioxidant status of mice skin exposed to a total dose of 10, 20 and 40 Gy γ-radiation below the rib cage delivered as a single fraction of 2 Gy per day for 5, 10 or 20 days. Skin biopsies from both the curcumin treated or untreated irradiated groups were collected for the biochemical estimations at various post-irradiation times. The irradiation of animals caused a dose dependent decline in the glutathione concentration, glutathione peroxidase, and superoxide dismutase activities and increased the lipid peroxidation in the irradiated skin. Curcumin treatment before irradiation resulted in a significant rise in the glutathione concentration and activities of both the glutathione peroxidase and superoxide dismutase enzymes in mouse skin, whereas lipid peroxidation declined significantly. The present study indicates that curcumin treatment increased the antioxidant status of mouse exposed to different doses of fractionated γ-radiation.

  2. The anti-tumor effect of ACNU and x-irradiation on mouse glioma

    International Nuclear Information System (INIS)

    Nakagawa, Hidemitsu; Hori, Masaharu; Hasegawa, Hiroshi; Mogami, Heitaro; Hayakawa, Toru.

    1979-01-01

    Anti-tumor activities of 1-(4-amino-2-methyl-5-pyrimidinyl)methyl-3-(2-chloroethyl)-3-nitrosourea hydrochloride (ACNU) and x-irradiation on methylcholanthrene induced glioma in C 57 BL mice were studied in vitro and in vivo. In vitro experiments using cultured glioma cells (MGB cells), the synchronization of cell cycle was done by excess addition of thymidine, and the anti-tumor cell effect were investigated by mean of determinations of DNA synthesis, mitotic index and the number of the living cells following the treatments. As the results, it appeared obvious that ACNU was most effective on MGB cells in S phase and x-irradiation in M phase. As to the combined therapy of ACNU and x-irradiation, the anti-tumor effect was most remarkable when the cells were treated by x-irradiation in the G 2 , M phase, which were hervested by addition of ACNU 44 hours before irradiation. However simultaneous treatment of ACNU and x-irradiation on the cells in G 1 phase was not so remarkable. In vivo experiments the anti-tumor effect of ACNU and x-irradiation on subcutaneously or intracranially transplanted glioma in mice was investigated. Either ACNU 10 mg/kg or local x-irradiation 1240 rads showed inhibitory effect on the tumor growth and prolonged the survival time of the tumor bearing mice. The combination therapy was more effective than ACNU or x-irradiation alone, particularly combination therapy of ACNU and repeated small doses irradiation of x-ray was remarkably effective. Evidence obtained indicated that the combination therapy of ACNU and x-irradiation have synergistic anti-tumor effect on experimental mouse glioma. (author)

  3. Multiple scroll wave chimera states

    Science.gov (United States)

    Maistrenko, Volodymyr; Sudakov, Oleksandr; Osiv, Oleksiy; Maistrenko, Yuri

    2017-06-01

    We report the appearance of three-dimensional (3D) multiheaded chimera states that display cascades of self-organized spatiotemporal patterns of coexisting coherence and incoherence. We demonstrate that the number of incoherent chimera domains can grow additively under appropriate variations of the system parameters generating thereby head-adding cascades of the scroll wave chimeras. The phenomenon is derived for the Kuramoto model of N 3 identical phase oscillators placed in the unit 3D cube with periodic boundary conditions, parameters being the coupling radius r and phase lag α. To obtain the multiheaded chimeras, we perform the so-called `cloning procedure' as follows: choose a sample single-headed 3D chimera state, make appropriate scale transformation, and put some number of copies of them into the unit cube. After that, start numerical simulations with slightly perturbed initial conditions and continue them for a sufficiently long time to confirm or reject the state existence and stability. In this way it is found, that multiple scroll wave chimeras including those with incoherent rolls, Hopf links and trefoil knots admit this sort of multiheaded regeneration. On the other hand, multiple 3D chimeras without spiral rotations, like coherent and incoherent balls, tubes, crosses, and layers appear to be unstable and are destroyed rather fast even for arbitrarily small initial perturbations.

  4. X-irradiation improves mdx mouse muscle as a model of myofiber loss in DMD

    International Nuclear Information System (INIS)

    Wakeford, S.; Watt, D.J.; Partridge, T.A.

    1991-01-01

    The mdx mouse, although a genetic and biochemical homologue of human Duchenne muscular dystrophy (DMD), presents a comparatively mild histopathological and clinical phenotype. These differences are partially attributable to the greater efficacy of regeneration in the mdx mouse than in DMD muscle. To lessen this disparity, we have used a single dose of X-irradiation (16 Gy) to inhibit regeneration in one leg of mdx mice. The result is an almost complete block of muscle fiber regeneration leading to progressive loss of muscle fibers and their replacement by loose connective tissue. Surviving fibers are mainly peripherally nucleated and, surprisingly, of large diameter. Thus, X-irradiation converts mdx muscle to a model system in which the degenerative process can be studied in isolation from the complicating effect of myofiber regeneration. This system should be of use for testing methods of alleviating the myofiber degeneration which is common to mdx and DMD

  5. X-irradiation improves mdx mouse muscle as a model of myofiber loss in DMD

    Energy Technology Data Exchange (ETDEWEB)

    Wakeford, S.; Watt, D.J.; Partridge, T.A. (Charing Cross and Westminster Medical School, London (England))

    1991-01-01

    The mdx mouse, although a genetic and biochemical homologue of human Duchenne muscular dystrophy (DMD), presents a comparatively mild histopathological and clinical phenotype. These differences are partially attributable to the greater efficacy of regeneration in the mdx mouse than in DMD muscle. To lessen this disparity, we have used a single dose of X-irradiation (16 Gy) to inhibit regeneration in one leg of mdx mice. The result is an almost complete block of muscle fiber regeneration leading to progressive loss of muscle fibers and their replacement by loose connective tissue. Surviving fibers are mainly peripherally nucleated and, surprisingly, of large diameter. Thus, X-irradiation converts mdx muscle to a model system in which the degenerative process can be studied in isolation from the complicating effect of myofiber regeneration. This system should be of use for testing methods of alleviating the myofiber degeneration which is common to mdx and DMD.

  6. Characteristic lesions in mouse retina irradiated with accelerated iron particles

    International Nuclear Information System (INIS)

    Malachowski, M.J.; Philpott, D.E.; Corbett, R.L.; Tobias, C.A.

    1981-01-01

    A program is underway to determine the radiation hazards of HZE particles using the Bevalac, a heavy-ion accelerator at LBL. Our earlier work with helium, carbon, neon, and argon particles, and exposure to rats to HZE particles in space flight demonstrated some deleterious biological effects. TEM studies have shown that some visual cells were missing and dislocated; these were termed channel lesions. Recently obtained is evidence that a single iron HZE particle may affect a series of cells. Mice were irradiated with 0.1, 0.3, 1, 10, or 25 rad of 590 MeV/amu initial kinetic energy iron particles in groups of 10 animals per dose point. Irradiated and control animals were sacrificed at intervals from one week to two years postirradiation. The eye samples were dehydrated, critical points dried with freon, fractured, and Au-Pd coated for SEM, or plastic embedded, sectioned, and stained for TEM. Additionally, dry fractured samples viewed with the SEM were embedded in plastic, sectioned, and stained for the TEM. Characteristic tunnel shaped lesions were observed with the SEM. Stereo pairs showed tunnels of various lengths up to 100 μm. Light microscopy of serially cut sections from the same material had vacuoles (V) extending the same length. TEM of the same specimen and specimens prepared only for TEM exhibited large vacuoles, greater than or equal to 2 μm, in the inner segment (IS) and outer segment (OS) layers. Severe membrane disruption was found bordering the vacuoles and gross nuclear degeneration (ND) and loose tissue (LT) were seen in the outer nuclear layer (ONL). The number of lesions increased with increasing dose. Microscopy of the control retina failed to demonstrate similar lesions

  7. Cell and tissue kinetics of the subependymal layer in mouse brain following heavy charged particle irradiation

    International Nuclear Information System (INIS)

    Manley, N.B.

    1988-01-01

    The following studies investigate the cellular response and cell population kinetics of the subependymal layer in the mouse brain exposed to heavy charged particle irradiation. Partial brain irradiation with helium and neon ions was confined to one cortex of the brain. Both the irradiated and the unirradiated contralateral cortex showed similar disturbances of the cell and tissue kinetics in the subependymal layers. The irradiated hemisphere exhibited histological damage, whereas the unirradiated side appeared normal histologically. The decrease in the values of the labeling indices 1 week after charged particle irradiation was dose- and ion-dependent. Mitotic indices 1 week after 10 and 25 Gy helium and after 10 Gy neon were the same as those seen in the control mice. Analysis of cell kinetics 1 week after 10 Gy helium and 10 Gy neon irradiation suggests the presence of a progenitor subpopulation that is proliferating with a shorter cell cycle. Comparison of the responses to the different charged particle beams indicates that neon ions are more effective in producing direct cellular damage than the helium ions, but the surviving proliferating cells several divisions later continue to maintain active cell renewal. Based on the 1 week post-irradiation H 3 -TdR labeling indices, a rough estimate of the RBE for neon ions is at least 2.5 when compared to helium ions

  8. The kinetics of repair in mouse lung after fractionated irradiation

    International Nuclear Information System (INIS)

    Travis, E.L.; Thames, H.D.; Watkins, T.L.; Kiss, I.

    1987-01-01

    The kinetics of repair of sublethal damage in mouse lung was studied after fractionated doses of 137 Cs γ-rays. A wide range of doses per fraction (1.7-12 Gy) was given with interfraction intervals ranging from 0.5 to 24 h. Data were analysed by a direct method of analysis using the incomplete repair model. The half-time of repair (Tsub(1/2)) was 0.76 h for the pneumonitis phase of damage (up to 8 months) and 0.65 h for the later phase of damage up to 12 months. Rate of repair was dependent on fraction size for both phases of lung damage and was faster after large dose fractions than after small fractions. Tsub(1/2) was 0.6 h (95% c.1. 0.53, 0.69) for doses per fraction greater than 5 Gy and 0.83 h (95% c.1. 0.76, 0.92) for doses per fraction of 2 Gy. Repair was nearly complete by 6 h at least for the pneumonitis phase of damage. If extrapolated to humans, these results imply that treatments with multiple fractions per day involving the lung will not be limited by the necessity for interfraction intervals much longer than 6 h. (author)

  9. Response of maternal immune cells of irradiation of mouse embryos

    International Nuclear Information System (INIS)

    Nicholls, E.M.; Markovic, B.

    1988-01-01

    This work began as an attempt to explain the paradox of pregnancy - the survival and growth of the semi-allogenic embryo in an immunologically hostile environment. In 1982 and 1983 we reported the tracing of quinacrine labelled maternal leukocytes (WBC) in maternal, placental and embryonic mouse tissues by fluorescence microscopy. We found that cells in the placenta phagocytose labelled WBC, so that after 1-2 hours the labelled nuclear DNA is found as brightly fluorescing particles in the cytoplasm of the phagocytes with no evidence of it in the nuclei. Identical cells were observed in slide preparations of embryos which had been carefully separated from their placentas. We also found a small population of intact labelled lymphocytes, clearly maternal in origin, in the embryos. This seems to be another paradox - placental phagocytes are observed to be phagocytosing maternal WBC in the placenta and embryo, but there are also free maternal cells in the placenta and embryo. A theoretical explanation is that maternal lymphocytes alloreactive against the embryo will attempt to react with placental cells and in the process be phagocytosed, while other maternal cells will be able to enter the embryo where they could have a surveillance function, removing dead or mutant embryonic cells. To test this theory a series of experiments were carried out and are reported

  10. Induction and repair of strand breaks and 3'-hydroxy terminals in the DNA of mouse brain following gamma irradiation

    International Nuclear Information System (INIS)

    Yoshizawa, K.; Furuno, I.; Yada, T.; Matsudaira, H.

    1978-01-01

    DNA was isolated from mouse brain after in vivo γ-ray irradiation, treated with endonuclease S 1 from Aspergillus oryzae if necessary, and analysed further by alkaline and neutral sucrose gradient centrifugation. In parallel, its template activity was determined by DNA polymerase (EC 2.7.7.7, enzyme A of Klenow from Escherichia coli) assay as described previously. Similar experiments were performed with cultured mouse leukaemia cells (L5178Y) irradiated in vitro at 0 0 C. (Auth.)

  11. Epithelial cell kinetics in mouse and rat skin irradiated with electrons

    International Nuclear Information System (INIS)

    McMaster-Schuyler, L.

    1984-02-01

    Experiments were performed to examine the kinetic responses of mouse and rat epidermal cells in vivo after single doses of ionizing radiation including responses of hair follicles at times after irradiation. The labeling indices in both species were reduced to 30 to 50% of control values immediately following irradiation at all the doses. In the rat, the labeling indices recovered and overshot control values within the first three days after 300 to 1200 rads. The mouse labeling indices continued to be suppressed for up to 10 days after 300 to 2400 rads. This indicated that rat G 1 phase epidermal cells recovered three times faster than those of the mouse with respect to the ability to maintain or increase control level cell proliferation after irradiation. After 1800 and 2400 rads, doses which produce skin ulceration, both species showed a reduction in their labeling indices for up to 7 days, indicating that a dose-dependent mechanism of recovery may be operable in the rat. 99 refs., 15 figs., 6 tabs

  12. Enstore with Chimera namespace provider

    International Nuclear Information System (INIS)

    Litvintsev, Dmitry; Moibenko, Alexander; Oleynik, Gene; Zalokar, Michael

    2012-01-01

    Enstore is a mass storage system developed by Fermilab that provides distributed access and management of data stored on tapes. It uses a namespace service, PNFS, developed by DESY to provide a filesystem-like view of the stored data. PNFS is a legacy product and is being replaced by a new implementation, called Chimera, which is also developed by DESY. Chimera offers multiple advantages over PNFS in terms of performance and functionality. The Enstore client component, encp, has been modified to work with Chimera, as well as with any other namespace provider. We performed high load end-to-end acceptance test of Enstore with the Chimera namespace. This paper describes the modifications to Enstore, the test procedure and the results of the acceptance testing.

  13. Studies on hematopoietic cell apoptosis and the relative gene expression in irradiated mouse bone marrow

    International Nuclear Information System (INIS)

    Peng Ruiyun; Wang Dewen; Xiong Chengqi; Gao Yabing; Yang Hong; Cui Yufang; Wang Baozhen

    2001-01-01

    Objective: To study apoptosis and expressions bcl-2 and p53 in irradiated mouse bone marrow. Methods: LACA mice were irradiated with 60 Co γ-rays. By means of in situ terminal labelling, in situ hybridization and image analysis, the authors studied radiation-induced apoptosis of hematopoietic cells and the expressions of bcl-2 and p53. Results: The characteristics of apoptosis appeared in hematopoietic cells at 6 hrs after irradiation. The expression of bcl-2 was obviously decreased when apoptosis of hematopoietic cells occurred, whereas it increased in the early recovery phase; p53 protein increased during both apoptosis of hematopoietic cells and the recovery phase, and mutant type p53 DNA was positive only in the recovery phase. Conclusion: Radiation may induced apoptosis of hematopoietic cells in a dose-dependent manner; Both bcl-2 and p53 genes play an important role in apoptosis and recovery phase

  14. The response of mouse skin to re-irradiation with x-rays or fast neutrons

    International Nuclear Information System (INIS)

    Tsukiyama, Iwao; Egawa, Sunao; Kumazawa, Akiyoshi; Iino, Yuu.

    1986-01-01

    Effects of neutrons and x-rays on mouse skin which had been previously irradiated with x-rays were investigated. Two tattoo marks were placed in the hairless legs of mice at intervals of 15 mm. The legs were exposed to various doses of x-ray and neutrons to determine the relative biological effectiveness (RBE) using the contraction of the skin as an index. The RBE was 0.93 - 1.73. The legs of the mice were preexposed to 25 Gy of x-ray, and exposed 4 months later. The contraction of the skin began earlier than after the first irradiation. RBE was 2.18 - 2.47. This RBE was higher than that in untreated mice. These results suggest that previously irradiated normal tissues are much more sensitive to neutrons than to x-rays. (author)

  15. Studies on the termination of immunological tolerance in the mouse thymus cell population after irradiation

    International Nuclear Information System (INIS)

    Amagai, Takashi

    1981-01-01

    Immunological tolerance in the mouse thymus cell population induced by the intravenous injection of deaggregated bovine gamma globulin was terminated by whole body irradiation. After irradiation, the weight of the thymus recovered biphasically, and the termination of tolerance occurred as early as in the first phase. Both Thy-1 antigen expression and helper activity of the thymus cell population in irradiated mice recovered in parallel with the recovery of the thymus weight. Sensitivity of the regenerating thymus cells to the tolerogen was not different from that of the normal thymus cells. The first phase of thymus regeneration may be caused by the proliferation and differentiation of relatively radioresistant and tolerogen insensitive precursors residing in the thymus. Tolerogen and/or immunogen reactive thymus cells may originate from the precursor. (author)

  16. Quantitative measurements of oxidative stress in mouse skin induced by X-ray irradiation

    International Nuclear Information System (INIS)

    Chi, Cuiping; Tanaka, Ryoko; Okuda, Yohei; Ikota, Nobuo; Ozawa, Toshihiko; Anzai, Kazunori; Yamamoto, Haruhiko; Urano, Shiro

    2005-01-01

    To find efficient methods to evaluate oxidative stress in mouse skin caused by X-ray irradiation, several markers and methodologies were examined. Hairless mice were irradiated with 50 Gy X-rays and skin homogenates or skin strips were prepared. Lipid peroxidation was measured using the skin homogenate as the level of thiobarbituric acid reactive substances. The level of lipid peroxidation increased with time after irradiation and was twice that of the control at 78 h. Electron spin resonance (ESR) spectra of skin strips showed a clear signal for the ascorbyl radical, which increased with time after irradiation in a manner similar to that of lipid peroxidation. To measure levels of glutathione (GSH) and its oxidized forms (GSSG) simultaneously, two high performance liquid chromatography (HPLC) methods, sample derivatization with 1-fluoro-2,4-dinitrobenzene and detection with a UV detector (method A) and no derivatization and detection with an electrochemical detector (method B), were compared and the latter was found to be better. No significant change was observed within 24 h after irradiation in the levels of GSH and GSSG measured by method B. The GSH/GSSG ratio may be a less sensitive parameter for the evaluation of acute oxidative stress caused by X-ray irradiation in the skin. Monitoring the ascorbyl radical seems to be a good way to evaluate oxidative stress in skin in vivo. (author)

  17. Strain-dependent Damage in Mouse Lung After Carbon Ion Irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Moritake, Takashi [Advanced Radiation Biology Research Program, Research Center for Charged Particle Therapy, National Institute of Radiological Sciences, Chiba (Japan); Proton Medical Research Center, University of Tsukuba, Tsukuba (Japan); Fujita, Hidetoshi; Yanagisawa, Mitsuru; Nakawatari, Miyako; Imadome, Kaori; Nakamura, Etsuko; Iwakawa, Mayumi [Advanced Radiation Biology Research Program, Research Center for Charged Particle Therapy, National Institute of Radiological Sciences, Chiba (Japan); Imai, Takashi, E-mail: imait@nirs.go.jp [Advanced Radiation Biology Research Program, Research Center for Charged Particle Therapy, National Institute of Radiological Sciences, Chiba (Japan)

    2012-09-01

    Purpose: To examine whether inherent factors produce differences in lung morbidity in response to carbon ion (C-ion) irradiation, and to identify the molecules that have a key role in strain-dependent adverse effects in the lung. Methods and Materials: Three strains of female mice (C3H/He Slc, C57BL/6J Jms Slc, and A/J Jms Slc) were locally irradiated in the thorax with either C-ion beams (290 MeV/n, in 6 cm spread-out Bragg peak) or with {sup 137}Cs {gamma}-rays as a reference beam. We performed survival assays and histologic examination of the lung with hematoxylin-eosin and Masson's trichrome staining. In addition, we performed immunohistochemical staining for hyaluronic acid (HA), CD44, and Mac3 and assayed for gene expression. Results: The survival data in mice showed a between-strain variance after C-ion irradiation with 10 Gy. The median survival time of C3H/He was significantly shortened after C-ion irradiation at the higher dose of 12.5 Gy. Histologic examination revealed early-phase hemorrhagic pneumonitis in C3H/He and late-phase focal fibrotic lesions in C57BL/6J after C-ion irradiation with 10 Gy. Pleural effusion was apparent in C57BL/6J and A/J mice, 168 days after C-ion irradiation with 10 Gy. Microarray analysis of irradiated lung tissue in the three mouse strains identified differential expression changes in growth differentiation factor 15 (Gdf15), which regulates macrophage function, and hyaluronan synthase 1 (Has1), which plays a role in HA metabolism. Immunohistochemistry showed that the number of CD44-positive cells, a surrogate marker for HA accumulation, and Mac3-positive cells, a marker for macrophage infiltration in irradiated lung, varied significantly among the three mouse strains during the early phase. Conclusions: This study demonstrated a strain-dependent differential response in mice to C-ion thoracic irradiation. Our findings identified candidate molecules that could be implicated in the between-strain variance to early

  18. Embryonic effects transmitted by male mice irradiated with 512 MeV/u 56Fe nuclei

    International Nuclear Information System (INIS)

    Wiley, L.M.; Van Beek, M.E.A.B.; Raabe, O.G.

    1994-01-01

    High-energy, high-charge nuclei may contribute substantially to the yearly equivalent dose in space flight from galactic cosmic radiation (GCR) at solar minimum. The largest single heavy-ion component is 56 Fe. We used the mouse embryo chimera assay to test 512 MeV/u 56 Fe nuclei for effects on the rate of proliferation of embryonic cells transmitted by sperm from irradiated mice. Male CD1 mice were acutely irradiated with 0.01, 0.05, or 0.1 Gy (LET, 184 keV/μm; fluence, 3.5 x 10 4 -3.3 x 10 5 nuclei/cm 2 ; average dose rate, 0.02 Gy/min) at the Lawrence Berkeley Laboratory BEVATRON/BEVALAC Facility in Berkeley, CA. Irradiated males were bred weekly for 7 weeks to nonirradiated females and their four-cell embryos were paired with control embryos, forming aggregation chimeras. After 30-35 h of culture, chimeras were dissociated to obtain open-quotes proliferation ratiosclose quotes (number of cells contributed by the embryo from the irradiated male/total number of cells in the chimera). Significant dose-dependent decreases in proliferation ratios were obtained across all three dose groups for postirradiation week 2 (P 56 Fe nuclei. However, up to 47% of sperm during postirradiation weeks 1 and 2 transmitted proliferation ratios that were at or below one standard deviation from control mean proliferation ratios. 26 refs., 4 figs., 10 tabs

  19. Autoradiographic study of gamma-irradiated mouse spleen during primary immune response

    International Nuclear Information System (INIS)

    Gitsov, L.G.; Kyncheva, L.S.; Burneva, V.G.; Martinova, J.Sh.; Viklichka, S.

    1978-01-01

    Study on the kinetics of the cells in the mouse spleen during the primary immune response against thymusdependent antigen after sublethal irradiation was carried out. For this purpose the animals were immunized with sheep erythrocytes one day after their irradiation with 700 r gamma rays. On the 5th day after the immunization, tritium labelled thymidine was injected three times at two hourly intervals. Mice were killed two hours after the third injection for preparation of routine histological samples and autoradiographs. Immunized, but not irradiated mice were utilized as controls. Extensive zones of lymphocyte destruction were observed in the spleen of the irradiated mice - accumulation of picnotic lymphocyte nuclei, surrounded by reticulo-histocyte elements. The number of the labelled cells and the intensity of labelled are lower than that of the germinal centres in control animal. There is no marked cell destruction in the periarteriolar zone nor labelled cells, whereas in the controls there is a considerable number of labelled blast cells. In the red pulp of the irradiated animals islands of erythroblasts were found, whereas in the controls - parallely to the erythroblast islands, there are islands of proliferating lymphocytes and plasmocytes. The decrease of lymphocyte number in irradiated mice is connected with their destruction and with the altered lymphocytopoiesis in the red pulp. It is assumed that the observed preservation of the periarteriolar lymphatic sheaths in an expression of a higher radioresistance of the T-cells as compared to the B-cells in the white pulp. This study contributes for elucidation of the irradiation immunosuppressive effect. It points out also that the post-irradiation lymphopaenia is due not only to the cell death but also to the exclusion of part of the T-lymphocytes from the circulation and their selective deposition in the thymus-dependent zones of the peripheral lymphoid organs. (A.B.)

  20. Reduction in sperm levels after testicular irradiation of the mouse: a comparison with man

    International Nuclear Information System (INIS)

    Meistrich, M.L.; Samuels, R.C.

    1985-01-01

    The potential and limitations of applying extrapolation factors (EFs) to the results of animal studies to predict effects of toxic agents on human male fertility were evaluated using radiation data. The EF is the ratio of the dose to produce a given effect in the mouse to that necessary to produce the same effect in man. Sperm counts in mouse testes were compared to those in the ejaculates of human males. Sperm counts performed at times at which the sperm develop from irradiated stem cells in both species yielded EFs between 11 and 44. However, if sufficient time was allowed for maximum recovery in both species, the EF was less than 1.7. These results indicate that man appears to be much more sensitive than the mouse to the testicular effects of irradiation at 2 to 9 months postexposure, but both species are comparable in their sensitivity to irreversible damage. The use of EFs may be appropriate, but since the EF is very dependent on the time at which the comparison was made, different values must be used for prompt and permanent testicular injury

  1. Mechanisms of tolerance in murine radiation bone marrow chimeras. I. Nonspecific suppression of alloreactivity by spleen cells from early, but not late, chimeras

    International Nuclear Information System (INIS)

    Auchincloss, H. Jr.; Sachs, D.H.

    1983-01-01

    Allogeneic chimeras were prepared using lethally irradiated B6 hosts and untreated marrow from exsanguinated BALB/c donors. For about two months after reconstitution, chimeras had very weak antihost cell-mediated lymphocytotoxicity (CML) reactivity and little third-party alloreactivity. During this time a cell population capable of suppressing CML reactivity against both host and third-party alloantigens (i.e., antigen-nonspecific) was demonstrated in chimera spleens by in vitro mixing experiments. The putative suppressor cells were Thy-1-negative and radiation-sensitive. Subsequently, mature chimeras showed host tolerance and strong third-party alloreactivity. At this point suppressor mechanisms could no longer be demonstrated. These data are consistent with a clonal elimination hypothesis in that they do not provide evidence to indicate that maintenance of specific immune tolerance is mediated by an active suppressor mechanism

  2. Cell cycle of spermatogonial colony forming stem cells in the CBA mouse after neutron irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Bootsma, A.L. (Rijksuniversiteit Utrecht (Netherlands). Academisch Ziekenhuis); Davids, J.A.G. (Netherlands Energy Research Foundation, Petten (Netherlands))

    1988-03-01

    In the CBA mouse testis, about 10% of the stem cell population is highly resistant to neutron irradiation (D/sub 0/, 0.75 Gy). Following a dose of 1.50 Gy these cells rapidly increase their sensitivity towards a second neutron dose and progress fairly synchronously through their first post-irradiation cell cycle. From experiments in which neutron irradiation was combined with hydroxyurea, it appeared that in this cycle the S-phase is less radiosensitive (D/sub 0/, 0.43 Gy) than the other phases of the cell cycle (D/sub 0/, 0.25 Gy). From experiments in which hydroxyurea was injected twice after irradiation, the speed of inflow of cells in S and the duration of S and the cell cycle could be calculated. Between 32 and 36 hr after irradiation cells start to enter the S-phase at a speed of 30% of the population every 12 hr. At 60 hr 50% of the population has already passed the S-phase while 30% is still in S. The data point to a cell cycle time of about 36 hr, while the S-phase lasts 12 hr at the most. (author).

  3. Early morphologic and quantitative changes in mouse peripheral blood lymphocytes after low dose gamma-irradiation

    International Nuclear Information System (INIS)

    Gitsov, L.; Byrneva, V.; Goranov, I.

    1979-01-01

    The study was undertaken in an effort to establish differences in the radiosensitivity of peripheral blood lymphocytes, as a possible test for evaluation of early and discrete radiation injury. Sexually mature mice of BAIB/c line were X-irradiated with doses of 50 and 250 rad. The animals were sacrificed by blood letting 24 hours after irradiation, but 30 minutes before this each mouse was heparinized. Smears were prepared from the enriched pooled leucocyte suspensions, obtained by dextran sedimentation of the red cells. The preparations were stained with toluidin blue by the methods of Smetana and Pappenheim. Cell size, clasmatosis, nucleolar structure and degree of cytoplasmic metachromasia were determined. It was found that the lymphocytogram of animals irradiated with 50 rad was characterized by high percentage of small lymphocytes, most of them with dispersed nuclear ribonucleoproteins and minimal clasmatose activity. Irradiation with 100 rad induced a characteristical rise in lymphocyte clasmatose activity and decrease in the number of small lymphocytes. The nucleoli were bright and well delineated. The lymphocytogram of animals irradiated with higher doses (150 and 250 rad) was characterized by predomination of large lymphocytes and hyperbasophilic forms with well preserved bright nucleoli. The percentage of lymphocates with clasmatosis was below the control value. (A.B.)

  4. Effect of gamma-irradiation on mouse pancreatic islet-allograft survival

    International Nuclear Information System (INIS)

    Kanai, T.; Porter, J.; Gotoh, M.; Monaco, A.P.; Maki, T.

    1989-01-01

    Elimination or inactivation of lymphoid tissue in the pancreatic islet preparation achieves prolongation of islet-allograft survival. In this study we examined the effect of gamma-irradiation on mouse islet-allograft survival. In a B6AF1 isograft model, irradiation up to 2400 rad did not induce deterioration of islet function over 200 days, but greater doses caused cessation of graft function between 83 and 186 days. When DBA/2 crude islets were transplanted into B6AF1 recipients, all nonirradiated allografts were acutely rejected. Marked prolongation of allograft survival was achieved by islet irradiation with doses between 800 and 12,000 rad. With higher doses, significant numbers of allografts survived beyond the controls, but many lost function between 78 and 180 days, with none surviving greater than 200 days. Irradiation with 16,000 rad caused acute radiation damage. Because most secondary islet allografts in recipient mice that lost primary islet-graft function between 84 and 195 days survived greater than 100 days, late functional loss was probably due to the radiation injury. Combined use of recipient treatment with cyclosporin A and graft irradiation (2400 rad) achieved prolongation of DBA/2 islets in B6AF1 mice

  5. Radioprotective effects of hawthorn fruit extract against gamma irradiation in mouse bone marrow cells

    International Nuclear Information System (INIS)

    Hosseinimehr, S.J.; Azadbakht, M.; Mousavi, S.M.; Mahmoudzadeh, A.; Akhlaghpoor, S.

    2007-01-01

    The radioprotective effect of hawthorn (Crataegus microphylla) fruit extract against genotoxicity induced by gamma irradiation has been investigated in mouse bone marrow cells. A single intraperitoneal (ip) administration of hawthorn extract at doses of 25, 50, 100 and 200 mg/kg 1 h prior to gamma irradiation (2 Gy) reduced the frequencies of micronucleated polychromatic erythrocytes (MnPCEs). All four doses of hawthorn extract significantly reduced the frequencies of MnPCEs and increased the PCE/PCE+NCE ratio (polychromatic erythrocyte/polychromatic erythrocyte+normochromatic erythrocyte) in mice bone marrow compared with the non drug-treated irradiated control (p<0.02-0.00001). The maximum reduction in MnPCEs was observed in mice treated with extract at a dose of 200 mg/kg. Administration of amifostine at dose 100 mg/kg and hawthorn at dose 200 mg/kg reduced the frequency of MnPCE almost 4.8 and 5.7 fold; respectively, after being exposed to 2 Gy of gamma rays, compare with the irradiated control group. Crataegus extract exhibited concentration-dependent activity on 1, 1-diphenyl 2-picrylhydrazyl free radical showing that Crataegus contained high amounts of phenolic compounds and the high performance liquid chromatography (HPLC) analysis determined that it contained chlorogenic acid, epicatechin and hyperoside. It appeared that hawthorn extract with antioxidant activity reduced the genotoxicity induced by gamma irradiation in bone marrow cells. (author)

  6. UV irradiation to mouse skin decreases hippocampal neurogenesis and synaptic protein expression via HPA axis activation.

    Science.gov (United States)

    Han, Mira; Ban, Jae-Jun; Bae, Jung-Soo; Shin, Chang-Yup; Lee, Dong Hun; Chung, Jin Ho

    2017-11-14

    The skin senses external environment, including ultraviolet light (UV). Hippocampus is a brain region that is responsible for memory and emotion. However, changes in hippocampus by UV irradiation to the skin have not been studied. In this study, after 2 weeks of UV irradiation to the mouse skin, we examined molecular changes related to cognitive functions in the hippocampus and activation of the hypothalamic-pituitary-adrenal (HPA) axis. UV exposure to the skin decreased doublecortin-positive immature neurons and synaptic proteins, including N-methyl-D-aspartate receptor 2 A and postsynaptic density protein-95, in the hippocampus. Moreover, we observed that UV irradiation to the skin down-regulated brain-derived neurotrophic factor expression and ERK signaling in the hippocampus, which are known to modulate neurogenesis and synaptic plasticity. The cutaneous and central HPA axes were activated by UV, which resulted in significant increases in serum levels of corticosterone. Subsequently, UV irradiation to the skin activated the glucocorticoid-signaling pathway in the hippocampal dentate gyrus. Interestingly, after 6 weeks of UV irradiation, mice showed depression-like behavior in the tail suspension test. Taken together, our data suggest that repeated UV exposure through the skin may negatively affect hippocampal neurogenesis and synaptic plasticity along with HPA axis activation.

  7. Cytogenetic studies in dogs after total body irradiation and allogeneic transfusion with cryopreserved blood mononuclear cells: observations in long-term chimeras

    International Nuclear Information System (INIS)

    Carbonell, F.; Calvo, W.; Fliedner, T.M.; Kratt, E.; Gerhartz, H.; Koerbling, M.; Nothdurft, W.; Ross, W.M.

    1984-01-01

    Cytogenetic studies were performed on two dog groups after total body irradiation and allogeneic transfusion with cryopreserved blood mononuclear cells. The first group of dogs was transfused with unseparated leukocytes and suffered from graft-versus-host disease (GvHD). Cytogenetic studies demonstrated only cells of donor origin in all dogs of this group. The second group of animals was transfused with fraction 2 of a discontinuous albumin gradient. The dogs of this group did not develop GvHD, and the cytogenetic studies showed the presence of a mosaic of cells from donor and recipient origin in all of them. These results suggest that the GvHD may suppress autochthonous regeneration

  8. Inducing and destruction of chimeras and chimera-like states by an external harmonic force

    Science.gov (United States)

    Shepelev, I. A.; Vadivasova, T. E.

    2018-03-01

    We study the phenomena of chimera destruction and inducing of chimera-like states in an ensemble of nonlocally coupled chaotic Rössler oscillators under an external harmonic force. The localized harmonic influence can lead to both destruction and changing of the spatial topology of chimeras. At the same time this influence can cause the emergence of stable chimera-like states (induced chimeras) for the regime of partial coherent chaos. Induced chimeras are also observed for the global influence. We show the possibility of controlling the chimera-like state topology by varying the parameters of localized external harmonic influence.

  9. Establishment of Early Endpoints in Mouse Total-Body Irradiation Model.

    Directory of Open Access Journals (Sweden)

    Amory Koch

    Full Text Available Acute radiation sickness (ARS following exposure to ionizing irradiation is characterized by radiation-induced multiorgan dysfunction/failure that refers to progressive dysfunction of two or more organ systems, the etiological agent being radiation damage to cells and tissues over time. Radiation sensitivity data on humans and animals has made it possible to describe the signs associated with ARS. A mouse model of total-body irradiation (TBI has previously been developed that represents the likely scenario of exposure in the human population. Herein, we present the Mouse Intervention Scoring System (MISS developed at the Veterinary Sciences Department (VSD of the Armed Forces Radiobiology Research Institute (AFRRI to identify moribund mice and decrease the numbers of mice found dead, which is therefore a more humane refinement to death as the endpoint. Survival rates were compared to changes in body weights and temperatures in the mouse (CD2F1 male TBI model (6-14 Gy, 60Co γ-rays at 0.6 Gy min-1, which informed improvements to the Scoring System. Individual tracking of animals via implanted microchips allowed for assessment of criteria based on individuals rather than by group averages. From a total of 132 mice (92 irradiated, 51 mice were euthanized versus only four mice that were found dead (7% of non-survivors. In this case, all four mice were found dead after overnight periods between observations. Weight loss alone was indicative of imminent succumbing to radiation injury, however mice did not always become moribund within 24 hours while having weight loss >30%. Only one survivor had a weight loss of greater than 30%. Temperature significantly dropped only 2-4 days before death/euthanasia in 10 and 14 Gy animals. The score system demonstrates a significant refinement as compared to using subjective assessment of morbidity or death as the endpoint for these survival studies.

  10. Generalized synchronization between chimera states

    Science.gov (United States)

    Andrzejak, Ralph G.; Ruzzene, Giulia; Malvestio, Irene

    2017-05-01

    Networks of coupled oscillators in chimera states are characterized by an intriguing interplay of synchronous and asynchronous motion. While chimera states were initially discovered in mathematical model systems, there is growing experimental and conceptual evidence that they manifest themselves also in natural and man-made networks. In real-world systems, however, synchronization and desynchronization are not only important within individual networks but also across different interacting networks. It is therefore essential to investigate if chimera states can be synchronized across networks. To address this open problem, we use the classical setting of ring networks of non-locally coupled identical phase oscillators. We apply diffusive drive-response couplings between pairs of such networks that individually show chimera states when there is no coupling between them. The drive and response networks are either identical or they differ by a variable mismatch in their phase lag parameters. In both cases, already for weak couplings, the coherent domain of the response network aligns its position to the one of the driver networks. For identical networks, a sufficiently strong coupling leads to identical synchronization between the drive and response. For non-identical networks, we use the auxiliary system approach to demonstrate that generalized synchronization is established instead. In this case, the response network continues to show a chimera dynamics which however remains distinct from the one of the driver. Hence, segregated synchronized and desynchronized domains in individual networks congregate in generalized synchronization across networks.

  11. Chimera states in three dimensions

    International Nuclear Information System (INIS)

    Maistrenko, Yuri; Sudakov, Oleksandr; Osiv, Oleksiy; Maistrenko, Volodymyr

    2015-01-01

    The chimera state is a recently discovered dynamical phenomenon in arrays of nonlocally coupled oscillators, that displays a self-organized spatial pattern of coexisting coherence and incoherence. In this paper, the first evidence of three-dimensional chimera states is reported for the Kuramoto model of phase oscillators in 3D grid topology with periodic boundary conditions. Systematic analysis of the dependence of the spatiotemporal dynamics on the range and strength of coupling shows that there are two principal classes of the chimera patterns which exist in large domains of the parameter space: (I) oscillating and (II) spirally rotating. Characteristic examples from the first class include coherent as well as incoherent balls, tubes, crosses, and layers in incoherent or coherent surrounding; the second class includes scroll waves with incoherent, randomized rolls of different modality and dynamics. Numerical simulations started from various initial conditions indicate that the states are stable over the integration time. Videos of the dynamics of the chimera states are presented in supplementary material. It is concluded that three-dimensional chimera states, which are novel spatiotemporal patterns involving the coexistence of coherent and incoherent domains, can represent one of the inherent features of nature. (paper)

  12. Unscheduled DNA synthesis after β-irradiation of mouse skin in situ

    International Nuclear Information System (INIS)

    Ootsuyama, Akira; Tanooka, Hiroshi

    1986-01-01

    The skin of ICR mouse was irradiated with β-rays from 90 Sr- 90 Y with surface doses up to 30 krad. Unscheduled DNA synthesis (UDS) was measured by autoradiography after labeling the skin with radioactive thymidine using the forceps-clamping method. The level of UDS in epithelial cells of the skin was detected as an increasing function of radiation dose. Fibroblastic cells, compared with epithelial cells and hair follicle cells at the same depth of the skin, showed a lower level of UDS, indicating a lower DNA repair activity in fibroblasts. Cancer risk of the skin was discussed. (Auth.)

  13. Origin of hemopoietic stromal progenitor cells in chimeras

    International Nuclear Information System (INIS)

    Chertkov, J.L.; Drize, N.J.; Gurevitch, O.A.; Samoylova, R.S.

    1985-01-01

    Intravenously injected bone marrow cells do not participate in the regeneration of hemopoietic stromal progenitors in irradiated mice, nor in the curetted parts of the recipient's marrow. The hemopoietic stromal progenitors in allogeneic chimeras are of recipient origin. The adherent cell layer (ACL) of long-term cultures of allogeneic chimera bone marrow contains only recipient hemopoietic stromal progenitors. However, in ectopic hemopoietic foci produced by marrow implantation under the renal capsule and repopulated by the recipient hemopoietic cells after irradiation and reconstitution by syngeneic hemopoietic cells, the stromal progenitors were of implant donor origin, as were stromal progenitors of the ACL in long-term cultures of hemopoietic cells from ectopic foci. Our results confirm that the stromal and hemopoietic progenitors differ in origin and that hemopoietic stromal progenitors are not transplantable by the intravenous route in mice

  14. Exogenous iron and γ-irradiation induce NO-synthase synthesis in mouse liver

    International Nuclear Information System (INIS)

    Mikoyan, V.D.; Voevodskaya, N.V.; Kubrina, L.N.; Malenkova, I.V.; Vanin, A.F.

    1994-01-01

    Protein synthesis inhibitor (cycloheximide, CHI) and exogenous antioxidant (phenazan) suppress the synthesis of NO in mouse liver in vivo which is induced by administration to the animals of γ-irradiation, bacterial lipopolysaccharide (LPS), or Fe 2+ -citrate together with LPS. Biosynthesis of NO was monitored by the ESR signal of paramagnetic mononitrosyl iron complexes with the exogenous ligand diethyldithiocarbamate (MNIC-DETC) 30 min after addition of the ligand. The complexes arise from NO binding to DETC complexes with exogenous and endogenous Fe 2+ , which act as selective NO traps. The enhancement of NO biosynthesis after γ-irradiation or LPS or LPS + Fe 2+ -citrate is apparently due to the induction of the synthesis of NO-synthase, which is inhibited by cycloheximide. This process is triggered by reactive oxygen species, presumably through the activation of the transcription factor protein NFkB. The accumulation of free radical oxygen species is inhibited by the antioxidant phenazan

  15. Automatic analysis of flow cytometric DNA histograms from irradiated mouse male germ cells

    International Nuclear Information System (INIS)

    Lampariello, F.; Mauro, F.; Uccelli, R.; Spano, M.

    1989-01-01

    An automatic procedure for recovering the DNA content distribution of mouse irradiated testis cells from flow cytometric histograms is presented. First, a suitable mathematical model is developed, to represent the pattern of DNA content and fluorescence distribution in the sample. Then a parameter estimation procedure, based on the maximum likelihood approach, is constructed by means of an optimization technique. This procedure has been applied to a set of DNA histograms relative to different doses of 0.4-MeV neutrons and to different time intervals after irradiation. In each case, a good agreement between the measured histograms and the corresponding fits has been obtained. The results indicate that the proposed method for the quantitative analysis of germ cell DNA histograms can be usefully applied to the study of the cytotoxic and mutagenic action of agents of toxicological interest such as ionizing radiations.18 references

  16. Cell cycle evaluation of granulosa cells in the {gamma}-irradiated mouse ovarian follicles

    Energy Technology Data Exchange (ETDEWEB)

    KIm, Jin Kyu; Lee, Chang Joo; Lee, Young Keun [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of); Song, Kang Won; Yoon, Yong Dal [Hanyang Univ., Seoul (Korea, Republic of)

    1999-03-01

    This study was carried out to evaluate the biochemical and morphological effects of ionizing radiation on mouse ovarian follicles. Immature mice (ICR, 3 week-old) were irradiated with a dose of LD{sub 80(30)} at KAERI. The ovaries were collected after 6 hours, 12 hours, 1 day, and 2 days post irradiation. With the morphological basis of the histological staining with hematoxylin-eosin, immunohistochemical preparation using in situ 3'-end labeling was evaluated. Flow cytometric evaluation of DNA extracted from the whole ovary was performed. The percentage of A{sub 0} (subpopulation of cells with degraded DNA and with lower DNA fluorescence than G{sub 0}/G{sub 1} cells), apoptotic, cells in the cell cycle was significantly higher in the irradiated group than in the control group. The number of in situ 3'-end labeled follicles increased at 6 hours post irradiation. All the analyses represented that the ionizing radiation-induced follicular atresia was taken place via an apoptotic degeneration. Such a degeneration underwent very fast and acutely. Therefore, it is concluded that the radiation-induced follicular degeneration is, like the spontaneous atresia, mediated by an acute apoptosis of follicular granulosa cells. Flow cytometric evaluation of cell cycles can make the role for quantifying the atretic follicles and understanding the mechanism of the radiation-induced cell death.

  17. H-2-incompatible bone marrow chimeras produce donor-H-2-restricted Ly-2 suppressor T-cell factor(s)

    International Nuclear Information System (INIS)

    Noguchi, M.; Onoe, K.; Ogasawara, M.; Iwabuchi, K.; Geng, L.; Ogasawara, K.; Good, R.A.; Morikawa, K.

    1985-01-01

    To study adaptive-differentiation phenomena of T lymphocytes, suppressor T-cell factors (TsF) produced by Ly-2+ splenic T cells from fully allogeneic mouse bone marrow chimeras were analyzed. AKR mice irradiated and reconstituted with B10 marrow cells (B10----AKR chimeras) produced an Ly-2+ TsF after hyperimmunization with sheep erythrocytes. The TsF suppressed primary antibody responses (to sheep erythrocytes) generated with spleen cells of mice of H-2b haplotype but not those of H-2k haplotype. Thus, this suppressor factor was donor-H-2-restricted. The immunoglobulin heavy chain variable region gene (Igh-V)-restricting element was not involved in this form of suppression. Similar results were obtained when TsF from B6----BALB/c and BALB/c----B6 chimeras were analyzed. The TsF from B10----AKR chimeras suppressed responses of B10.A(3R) and B10.A(5R) mice but not those of B10.A(4R). This finding showed that identity between the factor-producing cells and target spleen cells is required on the left-hand side of the E beta locus of the H-2 region and that the putative I-Jb locus is not involved in this form of suppression. The present results support the postulate that post-thymic differentiation in the presence of continued or repeated stimulation with antigen and donor-derived antigen-presenting cells generates donor-H-2-restricted T-cell clones that may predominate within the repertoire of the specific antigen being presented

  18. Petascale supernova simulation with CHIMERA

    Energy Technology Data Exchange (ETDEWEB)

    Messer, O E B [National Center for Computational Sciences, Oak Ridge National Laboratory, Oak Ridge, TN 37831-6008 (United States); Bruenn, S W [Department of Physics, Florida Atlantic University, 777 W Glades Road, Boca Raton, FL 33431-0991 (United States); Blondin, J M [Department of Physics, North Carolina State University, Raleigh, NC 27695-8202 (United States); Hix, W R [Physics Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831-6354 (United States); Mezzacappa, A [Physics Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831-6354 (United States); Dirk, C J [Department of Physics, Florida Atlantic University, 777 W Glades Road, Boca Raton, FL 33431-0991 (United States)

    2007-07-15

    CHIMERA is a multi-dimensional radiation hydrodynamics code designed to study core-collapse supernovae. The code is made up of three essentially independent parts: a hydrodynamics module, a nuclear burning module, and a neutrino transport solver combined within an operator-split approach. We describe some major algorithmic facets of the code and briefly discuss some recent results. The multi-physics nature of the problem, and the specific implementation of that physics in CHIMERA, provide a rather straightforward path to effective use of multi-core platforms in the near future.

  19. Radiobiological research on carnation chimerae Dianthus Caryophyllus L

    International Nuclear Information System (INIS)

    Pereau-Leroy, Pierre.

    1975-01-01

    A radiobiological study of periclinal carnation chimerae is carried out by subjecting whole plants and cuttings at different physiological stages to cobalt 60 gamma radiation under different dose and dose rate conditions. The effects of these treatments are observed during cultivation of the treated plants and by microscopic examination of irradiated meristem sections. The destruction of meristem cells in proportions varying with the irradiation conditions leads to structural changes in the chimerae; the more frequent change is the formation of genetically homogeneous stalks from different genotypes existing in the irradiated plant. Treatment by ionizing radiations is thus a practical means of detecting periclinical chimerae which, as in the case of carnations, are very common in plants grown by vegetative propagation. However since more than two independent meristem cell groups are usually present it is not possible by this method alone to define the distribution of the differentent genotypes in these groups; additional genetic studies or cell labelling such as chlorophyll or genoma mutations are then necessary [fr

  20. Restoring efficiency of hemopoietic cell transplantation in a mouse lethally irradiated by a total exposure to X rays

    International Nuclear Information System (INIS)

    Doria, Gino

    1959-10-01

    This research thesis reports the study of possibility of treatments (or restoration) of a mouse which has been submitted to a lethal dose of X rays. More particularly, the author compared the restoring efficiency of bone marrow and fetal liver injected in a mouse which had been lethally irradiated by a total exposure to X rays. He also studied the functional status of the hemopoietic graft, and the emergence of the secondary disease in mice which had been as well lethally irradiated and then restored by injection of bone marrow and fetal liver. The author then addressed the influence of the induction of immune tolerance of the host with respect to the donor on the survival of a mouse lethally irradiated and restored by homologue bone marrow [fr

  1. Effect of low dose X-ray irradiation on apoptosis in spermatogenic cells of mouse testes

    International Nuclear Information System (INIS)

    Liu Guangwei; Liu Shuchun; Lu Zhe; Gong Shouliang

    2003-01-01

    To study the effects of low dose radiation (LDR) with different doses of X-rays on the apoptosis in spermatogenic cells of male Kunming mouse testes. The time-effect and dose-effect of apoptosis in the different stages of spermatogenic cell cycles of mouse testis after LDR with different doses of X-rays were studied with light microscope using the methods of TdT-mediated dUTP nick end labeling (TUNEL) and HE staining. The apoptosis of spermatogenic cells induced by LDR had a remarkable regularity in cell types. When the dose was 0.025 Gy, spermatogonium apoptosis was taken as main. With the dose increase of irradiation (0.025-0.2 Gy), spermatocytes also showed an apoptotic change, but the apoptotic rate of spermatogonia was significantly higher than that of spermatocytes. Moreover, the apoptosis of spermatids and spermatozoa scarcely occurred after irradiation with low dose. The apoptosis of spermatogenic cells induced by LDR has a regular change, which provides a further experimental evidence for the mechanism study of hormesis by LDR

  2. Novel technique for high-precision stereotactic irradiation of mouse brains

    Energy Technology Data Exchange (ETDEWEB)

    Hartmann, J.; Woelfelschneider, J.; Derer, A.; Fietkau, R.; Gaipl, U.S.; Bert, C.; Frey, B. [Friedrich-Alexander-Universitaet Erlangen-Nuernberg, Department of Radiation Oncology, Universitaetsklinikum Erlangen, Erlangen (Germany); Stache, C.; Buslei, R.; Hoelsken, A. [Friedrich-Alexander-Universitaet Erlangen-Nuernberg, Institute of Neuropathology, Universitaetsklinikum Erlangen, Erlangen (Germany); Schwarz, M.; Baeuerle, T. [Friedrich-Alexander-Universitaet Erlangen-Nuernberg, Institute of Radiology, Preclinical Imaging Platform Erlangen (PIPE), Universitaetsklinikum Erlangen, Erlangen (Germany)

    2016-11-15

    Small animal irradiation systems were developed for preclinical evaluation of tumor therapy closely resembling the clinical situation. Mostly only clinical LINACs are available, so protocols for small animal partial body irradiation using a conventional clinical system are essential. This study defines a protocol for conformal brain tumor irradiations in mice. CT and MRI images were used to demarcate the target volume and organs at risk. Three 6 MV photon beams were planned for a total dose of 10 fractions of 1.8 Gy. The mouse position in a dedicated applicator was verified by an X-ray patient positioning system before each irradiation. Dosimetric verifications (using ionization chambers and films) were performed. Irradiation-induced DNA damage was analyzed to verify the treatment effects on the cellular level. The defined treatment protocol and the applied fractionation scheme were feasible. The in-house developed applicator was suitable for individual positioning at submillimeter accuracy of anesthetized mice during irradiation, altogether performed in less than 10 min. All mice tolerated the treatment well. Measured dose values perfectly matched the nominal values from treatment planning. Cellular response was restricted to the target volume. Clinical LINAC-based irradiations of mice offer the potential to treat orthotopic tumors conformably. Especially with respect to lateral penumbra, dedicated small animal irradiation systems exceed the clinical LINAC solution. (orig.) [German] Kleintierbestrahlungsanlagen wurden entwickelt um praeklinische Studien in der Tumortherapie unter moeglichst klinischen Bedingungen durchzufuehren. Da an den meisten Instituten nur klinische LINACs zur Verfuegung stehen, werden Standardprotokolle zur Kleintierbestrahlung benoetigt, die konventionelle Systeme nutzen. In dieser Studie wird ein solches Protokoll fuer tumorkonforme Hirnbestrahlung von Maeusen definiert. CT- und MRT-Bilder wurden aufgenommen, um Zielvolumen und

  3. Effects of continuous low-dose prenatal irradiation on neuronal migration in mouse cerebral cortex

    International Nuclear Information System (INIS)

    Hyodo-Taguchi, Yasuko; Ishikawa, Yuji; Hirobe, Tomohisa; Fushiki, Shinji; Kinoshita, Chikako.

    1997-01-01

    We investigated the effects of continuous exposure to γ-rays during corticogenesis on the migration of neuronal cells in developing cerebral cortex. Pregnant mice were injected with 0.5 mg of bromodeoxyuridine (BrdU) on day 14 of gestation to label cells in the S phase. The mice were then exposed to 137 Cs γ-rays (dose rates of 0.1, 0.3, and 0.94 Gy/day) continuously for 3 days. Brains from 17-day-old embryos and from offspring at 3 and 8 weeks after birth were processed immunohistochemically to track the movements of BrdU-labeled cells. Comparative analyses of the distribution pattern of BrdU-labeled cells in the cerebral cortex revealed that the migration of neurons was delayed during the embryonic period in mice irradiated at 0.94 Gy/day, in 3-week-old mice, there was a significant difference in the distribution pattern of BrdU-labeled cells in the cerebral cortex between the mice irradiated prenatally and control, and in 8-week-old mice, there were no differences in the distribution pattern of BrdU-labeled cells between control and animals irradiated with 0.1 and 0.3 Gy/day. In contrast, in the animals irradiated with 0.94 Gy/day, the significant difference in the distribution pattern of the labeled cells relative to control was maintained. These results suggest that the migration of neuronal cells in mouse cerebral cortex is disturbed by continuous prenatal irradiation at low-dose and some modificational process occurred during the postnatal period. (author)

  4. STI571 (Gleevec) improves tumor growth delay and survival in irradiated mouse models of glioblastoma

    International Nuclear Information System (INIS)

    Geng Ling; Shinohara, Eric T.; Kim, Dong; Tan Jiahuai; Osusky, Kate; Shyr, Yu; Hallahan, Dennis E.

    2006-01-01

    Purpose: Glioblastoma multiforme (GBM) is a devastating brain neoplasm that is essentially incurable. Although radiation therapy prolongs survival, GBMs progress within areas of irradiation. Recent studies in invertebrates have shown that STI571 (Gleevec; Novartis, East Hanover, NJ) enhances the cytotoxicity of ionizing radiation. In the present study, the effectiveness of STI571 in combination with radiation was studied in mouse models of GBM. Methods and Materials: Murine GL261 and human D54 GBM cell lines formed tumors in brains and hind limbs of C57BL6 and nude mice, respectively. GL261 and D54 cells were treated with 5 μmol/L of STI571 for 1 h and/or irradiated with 3 Gy. Protein was analyzed by Western immunoblots probed with antibodies to caspase 3, cleaved caspase 3, phospho-Akt, Akt, and platelet-derived growth factor receptor (PDGFR) α and β. Tumor volumes were assessed in mice bearing GL261 or D54 tumors treated with 21 Gy administered in seven fractionated doses. Histologic sections from STI571-treated mice were stained with phospho-Akt and phospho-PDGFR β antibodies. Kaplan-Meier survival curves were used to study the response of mice bearing intracranial implants of GL261. Results: STI571 penetrated the blood-brain barrier, which resulted in a reduction in phospho-PDGFR in GBM. STI571-induced apoptosis in GBM was significantly enhanced by irradiation. STI571 combined with irradiation induced caspase 3 cleavage in GBM cells. Glioblastoma multiforme response to therapy correlated with an increase in tumor growth delay and survival when STI571 was administered in conjunction with daily irradiation. Conclusion: These findings suggest that STI571 has the potential to augment radiotherapy and thereby improve median survival

  5. Effect of low dose x irradiation on the succinate dehydrogenase activity of guinea pig, rat and mouse tissues

    Energy Technology Data Exchange (ETDEWEB)

    Shah, V C; Bhatavdekar, J M; Aravinda Babu, K [Gujarat Univ., Ahmedabad (India). Dept. of Zoology

    1976-07-01

    The histochemical changes in succinate dehydrogenase (SDH) were investigated in pectoralis major muscle of guinea pig, rat and mouse after level X-irradiation (72 R and 240 R) and compared with control animals. Biochemical studies were carried out on liver, kidney, muscle (pectoralis major), adrenal and spleen of these animals after low dose local X-irradiation and compared with control animals. Changes in SDH activity were studied up to 72-h post-irradiation, which shows that low dose local X-irradiation leads to increased enzymic activity. The increase in enzymic activity was remarkable in mouse tissues as compared with guinea pig and rat. Adrenals of all the three animals showed significant activation after all the doses of radiation studied. The significance of these results, with special reference to oxidative metabolism, has been discussed.

  6. Recovery of the spermatogenetic epithelium in the mouse after irradiation with 1-MeV fission neutrons

    International Nuclear Information System (INIS)

    Aardweg, G.J.M.J. van den.

    1983-01-01

    In this thesis the recovery of the spermatogenetic epithelium in the mouse is studied after damage with 1-MeV fission neutrons. A severe depletion of A-spermatogonia and radiosensitive stem cells occurs after neutron irradiation. Recovery of the epithelium is initiated by surviving radioresistant stem cells giving rise to colonies, which grow into the empty seminiferous tubules. After discussing properties of normal and irradiated spermatogenetic epithelium, the growth and the differentiation of spermatogenetic colonies in the mouse testis after irradiation, as well as response and kinetics of colony-forming spermatogonial stem cells in CBA mice up to 30 weeks after a first neutron dose and recovery of the epithelium after a second irradiation are investigated. These four subjects are dealt with in separate papers. Finally, a discussion and a summary of these studies is presented. (Auth.)

  7. Lessons from Interspecies Mammalian Chimeras.

    Science.gov (United States)

    Suchy, Fabian; Nakauchi, Hiromitsu

    2017-10-06

    As chimeras transform from beasts of Greek mythology into tools of contemporary bioscience, secrets of developmental biology and evolutionary divergence are being revealed. Recent advances in stem cell biology and interspecies chimerism have generated new models with extensive basic and translational applications, including generation of transplantable, patient-specific organs.

  8. Chimera States in Neural Oscillators

    Science.gov (United States)

    Bahar, Sonya; Glaze, Tera

    2014-03-01

    Chimera states have recently been explored both theoretically and experimentally, in various coupled nonlinear oscillators, ranging from phase-oscillator models to coupled chemical reactions. In a chimera state, both coherent and incoherent (or synchronized and desynchronized) states occur simultaneously in populations of identical oscillators. We investigate chimera behavior in a population of neural oscillators using the Huber-Braun model, a Hodgkin-Huxley-like model originally developed to characterize the temperature-dependent bursting behavior of mammalian cold receptors. One population of neurons is allowed to synchronize, with each neuron receiving input from all the others in its group (global within-group coupling). Subsequently, a second population of identical neurons is placed under an identical global within-group coupling, and the two populations are also coupled to each other (between-group coupling). For certain values of the coupling constants, the neurons in the two populations exhibit radically different synchronization behavior. We will discuss the range of chimera activity in the model, and discuss its implications for actual neural activity, such as unihemispheric sleep.

  9. Combined effects of x-irradiation and bleomycin on the proliferation of isoproterenol-stimulated mouse parotid glands

    International Nuclear Information System (INIS)

    Shoju, Masumi

    1977-01-01

    Effects of x-irradiation and bleomycin (BLM) on DNA synthesis in isoproterenol (IPR)-stimulated mouse parotid glands were investigated. The incorporation of thymidine- 3 H into DNA in parotid glands increased remarkably in 16 hours with a peak at 22 hours after the injection of IPR. When x-irradiation (250 rads) was given at 1 hour after IPR (early G 1 phase), the stimulation of DNA synthesis was inhibited by about 50%, and the beginning of DNA synthesis was delayed nearly 6 hours. BLM injected in the early G 1 phase was also effective in inhibiting DNA synthesis. However, the injection of BLM in the late G 1 or S phase did not interfere with DNA synthesis. Combined x-irradiation and BLM inhibited DNA synthesis and delayed the beginning of the S phase far more strikingly than did x-irradiation alone. When BLM was injected at various intervals before and after x-irradiation, the greatest inhibition was found just after irradiation. Therefore, a longer interval between x-irradiation and BLM injection had a tendency to decrease the rate of inhibiting DNA synthesis. These findings were confirmed by measuring the labeling index and the mitotic index in the acinar cells of the mouse parotid gland. These results suggest that simultaneous application of x-irradiation and BLM has the greatest effect. (Evans, J.)

  10. In vitro and in vivo studies on the cytotoxicity of irradiated silk fibroin against mouse melanoma tumor cell

    International Nuclear Information System (INIS)

    Byun, Eui-Baek; Sung, Nak-Yun; Kwon, Sun-Kyu; Song, Beom-Seok; Kim, Jae-Hun; Choi, Jong-il; Hwang, Han-Joon; Byun, Myung-Woo; Lee, Ju-Woon

    2009-01-01

    The physicochemical properties of proteins can be altered by irradiation. But, it is rarely that the researches on the functional properties of irradiated proteins have been reported. Fibroin is a fibrous protein derived from silkworm Bombyx mori and has been suggested as a biomaterial for biomedical application. Therefore, fibroin was selected as a model protein and was examined with the irradiation effects on the cytotoxicity of fibroin on tumor cell. The cytotoxicity of fibroin against mouse melanoma cell (B16BL6) showed a significant increase dependent upon the increase of irradiation dose. And also, the splenocyte proliferation activities of fibroin were increased by gamma irradiation. In addition, the oral administration of irradiated fibroin significantly increased the inhibition rate of tumor growth in tumor-bearing mouse model. The reason might be due to the change of protein structure by gamma irradiation and is being studied. From these result, it could be concluded that the irradiated fibroin might be a potential candidate as a valuable product in food and medical industry.

  11. In vitro and in vivo studies on the cytotoxicity of irradiated silk fibroin against mouse melanoma tumor cell

    Energy Technology Data Exchange (ETDEWEB)

    Byun, Eui-Baek [Team for Radiation Food Science and Biotechnology, Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup 580-185 (Korea, Republic of); Division of Bioresources and Biosciences, Faculty of Agriculture, Graduate school of Kyushu University, 6-10-1 Hakozaki, Fukuoka 812-8581 (Japan); Sung, Nak-Yun [Team for Radiation Food Science and Biotechnology, Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup 580-185 (Korea, Republic of); Kwon, Sun-Kyu [Team for Radiation Food Science and Biotechnology, Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup 580-185 (Korea, Republic of); Graduate school of Food and Biotechnology, Korea University, Jochiwon 339-800 (Korea, Republic of); Song, Beom-Seok; Kim, Jae-Hun; Choi, Jong-il [Team for Radiation Food Science and Biotechnology, Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup 580-185 (Korea, Republic of); Hwang, Han-Joon [Graduate school of Food and Biotechnology, Korea University, Jochiwon 339-800 (Korea, Republic of); Byun, Myung-Woo [Team for Radiation Food Science and Biotechnology, Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup 580-185 (Korea, Republic of); Lee, Ju-Woon [Team for Radiation Food Science and Biotechnology, Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup 580-185 (Korea, Republic of)], E-mail: sjwlee@kaeri.re.kr

    2009-07-15

    The physicochemical properties of proteins can be altered by irradiation. But, it is rarely that the researches on the functional properties of irradiated proteins have been reported. Fibroin is a fibrous protein derived from silkworm Bombyx mori and has been suggested as a biomaterial for biomedical application. Therefore, fibroin was selected as a model protein and was examined with the irradiation effects on the cytotoxicity of fibroin on tumor cell. The cytotoxicity of fibroin against mouse melanoma cell (B16BL6) showed a significant increase dependent upon the increase of irradiation dose. And also, the splenocyte proliferation activities of fibroin were increased by gamma irradiation. In addition, the oral administration of irradiated fibroin significantly increased the inhibition rate of tumor growth in tumor-bearing mouse model. The reason might be due to the change of protein structure by gamma irradiation and is being studied. From these result, it could be concluded that the irradiated fibroin might be a potential candidate as a valuable product in food and medical industry.

  12. The co-application effects of fullerene and ascorbic acid on UV-B irradiated mouse skin

    International Nuclear Information System (INIS)

    Ito, Shinobu; Itoga, Kazuyoshi; Yamato, Masayuki; Akamatsu, Hirohiko; Okano, Teruo

    2010-01-01

    The role of fullerene as a pro-oxidant or anti-oxidant in Ultraviolet B ray (UV-B)-induced disorders in mouse skin was investigated. Fullerene gave no photo-toxic effect to UV-B-irradiated mouse skin. Since erythema was concentrated at the pore circumference in a UV-B irradiation experiment in mouse skin, the sebaceous gland pairs was strongly implicated as a site for the generation of reactive oxygen species (ROS). In a histological evaluation of the skin stained with CH 3 MDFDA (ROS index) and YO-Pro-1 (apoptosis index), the fluorescence intensity of a sebaceous gland significantly increased with UV-B irradiation. With the application of fullerene to UV-irradiated mouse skin, no toxicity was recognized in comparison with the control, and erythema, the ROS index, and the apoptosis index decrease with the application of fullerene. Ascorbyl radical (AA·) increased with the application of ascorbate (AA) to UV-B-irradiated mouse skin, and AA· decreased with the application of fullerene. The co-application of AA and fullerene, which suppressed AA· in vitro, significantly suppressed erythema, and also suppressed both the ROS index and apoptosis index in mouse skin after UV-B irradiation. In both mouse skin at 48 h after UV-B irradiation and in an attempt to reproduce this phenomenon artificially in vitro, a similar high AA· peak (AA·/H· > 4) was observed in electron spin resonance (ESR) charts. The binding of fullerene with AA impairs the Fenton reaction between AA and Fe-protein based on the observation of ascorbate-specific UV absorption and a linear equation for the calibration curve. Therefore, fullerene may impair the intercalation of AA to a heme pocket by binding with AA. These results suggest that the co-application of AA and fullerene is effective against oxidative skin damage caused by UV-B irradiation, and the development of an AA· inhibitor such as fullerene should be useful for reducing organ damage associated with Fe-protein oxidation.

  13. The proliferative activity of testicular cell types and the effect of postnatal X-irradiation in the developing mouse testis

    International Nuclear Information System (INIS)

    Vergouwen, R.P.F.A.; Huiskamp, R.; Davids, J.A.G.; Rooij, D.G. de

    1991-01-01

    The authors describe the effects of x-irradiation on the developing mouse testis, particularly in relation to A spermatogonia, Sertoli cells, Leydig cells and mesenchymal cells commonly regarded as Leydig precursors. It was concluded that radiosensitivity is highest during the first week after birth and decreases thereafter, with the exception of A spermatogonia which are radiosensitive at all ages. (UK)

  14. Type C virus activation in nontransformed mouse cells by uv-irradiated herpes simplex virus

    International Nuclear Information System (INIS)

    Hampar, B.; Hatanaka, M.; Aulakh, G.; Derge, J.G.; Lee, L.; Showalter, S.

    1977-01-01

    Infection of nontransformed mouse cells with uv-irradiated herpes simplex virus (uv-HSV) resulted in the activation of an endogenous xenotropic (x-tropic) type C virus. Synthesis of type C virus persisted for only a few days, with most of the virus remaining cell associated. The levels of type C virus activated by uv-HSV varied depending on the multiplicity of infection (m.o.i.) and the uv dose. At low uv doses, where cell killing occurred, little or no type C virus synthesis was observed. Maximum levels of type C virus synthesis were observed with the minimum uv dose which eliminated cell killing by HSV. Synthesis of type C virus, albeit at lower levels, was still observed at uv doses beyond those required to prevent cell killing

  15. Type C virus activation in nontransformed mouse cells by uv-irradiated herpes simplex virus

    Energy Technology Data Exchange (ETDEWEB)

    Hampar, B. (National Institutes of Health, Bethesda, MD); Hatanaka, M.; Aulakh, G.; Derge, J.G.; Lee, L.; Showalter, S.

    1977-02-01

    Infection of nontransformed mouse cells with uv-irradiated herpes simplex virus (uv-HSV) resulted in the activation of an endogenous xenotropic (x-tropic) type C virus. Synthesis of type C virus persisted for only a few days, with most of the virus remaining cell associated. The levels of type C virus activated by uv-HSV varied depending on the multiplicity of infection (m.o.i.) and the uv dose. At low uv doses, where cell killing occurred, little or no type C virus synthesis was observed. Maximum levels of type C virus synthesis were observed with the minimum uv dose which eliminated cell killing by HSV. Synthesis of type C virus, albeit at lower levels, was still observed at uv doses beyond those required to prevent cell killing.

  16. Crypt cell population kinetics in mouse jejunum under continuous beta irradiation from tritiated water

    International Nuclear Information System (INIS)

    Bhatia, A.L.; Gupta, M.L.; Saharan, B.R.

    1979-01-01

    The behaviour of crypt cell population in mouse jejunum under continuous beta irradiation from tritiated water (HTO) has been studied. Adult mice were maintained on tritiated drinking water of the activity of 1.25 μCi/ml, after priming injection. The crypts were studied at 1, 5, 7, 15 and 30 days after the initiation of treatment. It is observed that there is a partial recovery in proliferative activity after the first day of the treatment. Again there is a decrease in the crypt cells on the 7th day, after which this population appears to achieve a near-steady-state level at about 8% below normal at the last interval studied. Crypt cell population and mitotic figures showed a simultaneous dip and recovery, while dead cells showed inverse relationship. (orig.) [de

  17. Differentiation of hematopoietic stem cells in irradiated mouse thymic lobes. Kinetics and phenotype of progeny

    International Nuclear Information System (INIS)

    Spangrude, G.J.; Scollay, R.

    1990-01-01

    To define cell populations which participate in the very early stages of T cell development in the mouse thymus, we enriched hematopoietic stem cells from mouse bone marrow and injected them into thymic lobes of irradiated Ly-5 congenic recipients. The progeny of the stem cells were identified and their phenotypes were determined by two-color flow cytometry for the expression of various cell surface differentiation Ag during the course of their subsequent intrathymic development. The majority of the differentiation which occurred in the first 10 days after intrathymic cell transfer was myeloid in nature; hence, this study demonstrates that the irradiated thymus is not strictly selective for T cell development. Further, the maximum rate of T cell development was observed after intrathymic injection of 200 stem cells. Donor-derived cells which did not express Ag characteristic of the myeloid lineage could be detected and their phenotypes could be determined by flow cytometry as early as 7 days after intrathymic injection. At this time, the cells were still very similar phenotypically to the bone marrow hematopoietic stem cells. Exceptions to this were the expression of stem cell Ag 2 and a decrease in the level of MHC class I Ag expression. After 9 days, the donor-derived cells expressed high levels of the Thy-1 Ag and proceeded to change in cell surface phenotype as differentiation continued. These cell phenotypes are described for the time frame ending 18 days after injection, when most donor-derived cells were phenotypically small CD4+ CD8+ (double-positive) thymocytes

  18. Post-irradiation regeneration of early B-lymphocyte precursor cells in mouse bone marrow

    International Nuclear Information System (INIS)

    Park, Y.-H.; Osmond, D.G.

    1989-01-01

    To examine the sequential development of early B-cell precursors in mouse bone marrow, B-lineage cells have been examined during a wave of post-irradiation regeneration. Cell phenotypes have been defined for (i) terminal deoxynucleotidyl transferase (TdT); (ii) B220 glycoprotein, (iii) μ heavy chains in the cytoplasm (cμ) and at the cell surface (sμ). Three populations of μ - cells (TdT + 14.8 - ; TdT + 14.8 + ; TdT - 14.8 + ) have been proposed to be early B-cell precursors which would give rise to cμ + sμ - pre-B cells and to sμ + B lymphocytes. The timing, cell-size shifts and progressive amplification of the waves of regeneration accord with a dynamic model in which the TdT + 14.8 - , TdT + 14.8 + and TdT - 14.8 + cells form three successive stages in B-cell differentiation before the expression of μ chains, presumptively including the stage of μ chain gene rearrangement. In addition, the results provide an experimental system for the enrichment of early B-cell precursors in mouse bone marrow. (author)

  19. Tolerance, immunocompetence, and secondary disease in fully allogeneic radiation chimeras

    International Nuclear Information System (INIS)

    Rayfield, L.S.; Brent, L.

    1983-01-01

    The aim of this study was to ascertain the extent to which secondary disease and mortality in fully allogeneic chimeras (C57BL leads to CBA) is caused (if at all) by a delayed graft-versus-host reaction. Adult CBA males were thymectomized, irradiated, and reconstituted with T-lymphocyte-depleted C57BL or CBA bone marrow cells (BMC), followed three weeks after irradiation by implantation under the kidney capsule of thymic lobes from C57BL or CBA fetal or adult donors. These mice were observed for the development of secondary disease for periods in excess of 250 days, and they were examined at 5 weeks or 4 months for T lymphocyte reactivity and tolerance to alloantigens, using the cell-mediated lympholysis assay (CML). The following results were obtained. First, removal of T lymphocytes with anti-Thy 1 antibody and complement from allogeneic bone marrow did not prevent wasting and eventual death, although it prolonged the lifespan of mice substantially. Second, T lymphocytes generated from bone marrow-derived precursor cells became tolerant of the histocompatibility antigens of the thymus donor strain but remained normally reactive to third-party antigens. Third, allogeneic radiation chimeras did not survive as well as animals reconstituted with syngeneic cells, even when they were demonstrably tolerant in CML. Fourth, C57BL BMC maturing in a CBA host equipped with a C57BL thymus graft did not become tolerant of host antigens, indicating that extra-thymic tolerance does not occur in fully allogeneic--as opposed to semiallogeneic--chimeras. It is argued that the function of B lymphocytes and/or accessory cells is impaired in fully allogeneic radiation chimeras, and that the mortality observed was directly related to the resulting immunodeficiency. The relevance of the results described in this paper to clinical bone marrow transplantation is discussed

  20. The effects of 60Co γ-ray irradiation on cytoplasmic microtubules of mouse macrophages and lymphocytes

    International Nuclear Information System (INIS)

    Li Qianqian; Mao Zijun; Yin Zhiwei; Hu Yumin

    1989-05-01

    The effects of 60 Co γ-ray irradiation on cytoplasmic microtubules of mouse macrophages and lymphocytes were investigated by immunofluorescence microscopy and scanning electron microscope. The results indicated. (1) microtubule organization of the irradiated cells remarkably differed from that of the control since the doses over 4 Gy; (2) 144 hours after irradiation the alterations of microtubules have been shown to be basically r epaired ; (3) the cytoplasmic microtubules and centrioles disappeared under transmission electron microscope, the membranes irradiated and microvilli showed changes under scanning electron microscope too. From these observations and those of other workers who studied the radiation effect on extracted microtubule proteins in vitro, the authors support that 60 Co γ-ray irradiation can inhabits cytoplasmic microtubule assembling

  1. Recent results of CHIMERA activity

    Directory of Open Access Journals (Sweden)

    Pagano A.

    2012-07-01

    Full Text Available The experimental activity of CHIMERA in recent years has been characterized by a steady progress in the detection technique and data analysis. Since 2008 the detector system benefits of new implementations: a new reaction chamber, a new charged particle identification in silicon detector made by an extended pulse shape method and an efficient system for the identification of exotic beams produced by projectile-like fragmentation (In-flight method. These implementations appear to be promising tools in view of further exclusive experiments in the field of isospin physics. The coupling of CHIMERA with other equipments (such as interferometers and highly segmented arrays, magnetic elements, neutron detectors, etc. is also envisaged in order to extend the studies of the reaction mechanism in heavy ion physics.

  2. Mobility-induced persistent chimera states

    Science.gov (United States)

    Petrungaro, Gabriela; Uriu, Koichiro; Morelli, Luis G.

    2017-12-01

    We study the dynamics of mobile, locally coupled identical oscillators in the presence of coupling delays. We find different kinds of chimera states in which coherent in-phase and antiphase domains coexist with incoherent domains. These chimera states are dynamic and can persist for long times for intermediate mobility values. We discuss the mechanisms leading to the formation of these chimera states in different mobility regimes. This finding could be relevant for natural and technological systems composed of mobile communicating agents.

  3. Survival of mouse testicular stem cells after γ or neutron irradiation

    International Nuclear Information System (INIS)

    Lu, C.C.; Meistrich, M.L.; Thames, H.D. Jr.

    1980-01-01

    The survival of mouse testicular stem cells after γ or neutron irradiation was measured by counts of repopulated tubular cross sections and by the numbers of differentiated spermatogenic cells produced. The numbers of such cells were determined either by sperm head counts of the X-isozyme of lactate dehydrogenase enzyme levels. Qualitatively similar results were obtained with all three assays. The results have confirmed that, with C3H mice, stem-cell survival is higher when the γ-radiation dose is fractionated by a 24-h interval. Single-dose γ-radiaton survival curves for the stem cell had large shoulders and also showed the presence of a radioresistant subpopulation which predominated after doses greater than 600 rad. Part of the shoulder must have resulted from repair of sublethal damage since neutron irradiation produced survival curves with smaller shoulders. The relative biological effectiveness for stem-cell killing for these neutrons (mean energy, 22 MeV) varied from about 2.9 at 10 rad of γ radiation to 2.2 at 600 rad

  4. Fragmentation of chromatin DNA in mouse thymus cells after whole body γ-irradiation

    International Nuclear Information System (INIS)

    Wei Kang; Liu Xueying; Zhu Xuefen

    1984-01-01

    The characteristics of soluble chromatin in mouse thymus nuclei after whole body γ-irradiation were investigated by means of polyacrylamide gel electrophoresis. After deproteinization and electrophoresis eight regular DNA bands were revealed. The molecular weights of these bands were estimated by comparing their migration rates with those of the standard fragments obtained from PBR 322 digested completely by restrictive endonuclease Hae III. The molecular weight of the first band was calculated to be 186 base pairs corresponding approximately to the size of DNA fragment from a single nucleosome, and those of other bands appeared to be its multiples. The results suggested that the disintegration of chromatin DNA after γ-irradiation might have occurred at the linkage regions of chromatin. The autolysis product of normal thymus chromatin under sterile condition were also analyzed and its electrophoretic pattern was found to be just the same as that of the postirradiation product. It seems, therefore, that the endonuclease existing in normal tissues might be responsible for the postirradiation chromatin degradation. The mechanism of this kind of enzymatic digestion remains to be elucidated in further investigation. (author)

  5. Accelerated repopulation of mouse tongue epithelium during fractionated irradiations or following single doses

    International Nuclear Information System (INIS)

    Doerr, W.; Kummermehr, J.

    1990-01-01

    Mouse tongue mucosa was established as an animal model to study repopulation after large single doses or during continuous irradiation. A top-up irradiation technique was used employing priming doses or fractionated treatment to the whole snout (300 kV X-rays) followed by local test doses (25 kV X-rays) to elicit denudation in a confined field of the inferior tongue surface. Clearcut quantal dose-response curves of ulcer incidence were obtained to all protocols; animal morbidity, i.e. body weight loss was minimal. Repopulation following priming doses of 10 and 13 Gy started with a delay of at least 3 days and then progressed rapidly to nearly restore original tissue tolerance by day 11. During continuous fractionation over 1 to 3 weeks with 5 fractions/week and doses per fraction of 2.5, 3 and 3.5 Gy, repopulation was small in week one but subsequently increased to fully compensate the weekly dose at all dose levels. Additional measurements of cell density during a 4 weeks course of 5 x 3 Gy or 5 x 4 Gy per week showed only moderate depletion to 67% of the control figures. The fact that rapid repopulation is achieved at relatively moderate damage levels should be taken into account when the timing of a treatment split is considered. (author). 18 refs.; 7 figs.; 1 tab

  6. Validity of reciprocity rule on mouse skin thermal damage due to CO2 laser irradiation

    Science.gov (United States)

    Parvin, P.; Dehghanpour, H. R.; Moghadam, M. S.; Daneshafrooz, V.

    2013-07-01

    CO2 laser (10.6 μm) is a well-known infrared coherent light source as a tool in surgery. At this wavelength there is a high absorbance coefficient (860 cm-1), because of vibration mode resonance of H2O molecules. Therefore, the majority of the irradiation energy is absorbed in the tissue and the temperature of the tissue rises as a function of power density and laser exposure duration. In this work, the tissue damage caused by CO2 laser (1-10 W, ˜40-400 W cm-2, 0.1-6 s) was measured using 30 mouse skin samples. Skin damage assessment was based on measurements of the depth of cut, mean diameter of the crater and the carbonized layer. The results show that tissue damage as assessed above parameters increased with laser fluence and saturated at 1000 J cm-2. Moreover, the damage effect due to high power density at short duration was not equivalent to that with low power density at longer irradiation time even though the energy delivered was identical. These results indicate the lack of validity of reciprocity (Bunsen-Roscoe) rule for the thermal damage.

  7. Allogeneic unresponsiveness to orthotopic cardiac transplants in DL-A-identical radiation chimeras

    International Nuclear Information System (INIS)

    Boyd, A.D.; Spencer, F.C.; Hirose, H.; Engelman, R.M.; Cannon, F.D.; Ferrebee, J.W.; Rapaport, F.T.

    1975-01-01

    Nine Cooperstown beagles of known DL-A genotypes were exposed to supralethal total-body irradiation and received bone-marrow allografts from DL-A-identical donors. Four to 5 months later, the resulting chimeras received orthotopic cardiac allografts from their corresponding donors of marrow. Six chimeras died of operative complications in the immediate postoperative period. The other 3 chimeras survived from 173 to 547 days; 1 dog died at 173 days as a result of right-sided heart failure, secondary to stenosis at the site of the pulmonary artery anastomosis. The other two recipients continue to be active and healthy at 545 and 547 days. The results indicate that dogs can be rendered specifically tolerant to orthotopic cardiac allografts by supralethal total-body irradiation and the transplantation of marrow obtained from the prospective allograft donor

  8. Periclinal chimera technique: new plant breeding approach.

    Science.gov (United States)

    Gakpetor, P M; Mohammed, H; Moreti, D; Nassar, N M A

    2017-09-21

    Plant interspecific periclinal chimeras are a mosaic formed by tissues from two species. They are manipulated here as an efficient plant breeding tool for cassava root yields. In this study, plants synthesized from two chimeras, designated as chimera 2 and chimera 4, were characterized morphologically and cytologically to unravel the origin of their tissue layers (L2 and L3). Root yield of the two chimeras was also evaluated. Chimera 2 that was developed from graft union between Manihot fortalezensis (F) as scion and M. esculenta (E) as rootstock and the same in chimera 4 was developed from grafting triploid cassava cultivar (2n = 54) (C) as scion and M. pohlii (P) (2n = 36) as rootstock. A new method of inducing interspecific chimeras without using hormones was also tested in this study. Five combinations between four cassava cultivars on one side and M. fortalezensis and an interspecific hybrid (M. glaziovii x M. esculenta) on the other side were experimented to determine compatibility between the parents. Wild species always gave L2 and L3, independent of being used as rootstock or scion. L3 is responsible for producing pericycle. Thus, its performance was different in each chimera due to specific epigenetic interaction. Of 48 grafts, it was obtained one chimera giving a percentage of 2.1% that is little lower than using hormones but much efficient to use. Chimera induction efficiency in this investigation was the same when using hormones. Thus, our new, less labor, and more cost-effective technique is as much efficient as hormones and is much potential to employ as an effective plant breeding method boosting cassava root yield.

  9. Radiobiological effects on transcriptome in mouse thyroid after irradiation with AT-211

    International Nuclear Information System (INIS)

    Rudqvist, N.; Parris, T.; Nemes, S.; Helou, K.; Forssell-Aronsson, E.

    2013-01-01

    The full text of the publication follows. At-211 is an alpha particle emitting halogen used in radiation therapy, and is accumulated in the thyroid gland. Knowledge of biological processes that occur after irradiation is of high value in radiation therapy. Also, the behavior of thyrocytes after At-211 irradiation is to a high degree unknown. Female BALB/c nude mice were i.v. injected with At-211; absorbed dose to the thyroid was 0.05-32 Gy. Total RNA was extracted from pooled thyroids that were removed 24 hours after injection and processed in triplicate using Illumina Mouse Ref-8 Whole-Genome Expression Bead-chips. Nexus Expression 2.0 was used for data analysis. Compared with non-irradiated controls, 1225 (887 Down, 338 Up), 1636 (1156 Down, 480 Up), 544 (260 Down, 284 Up), 575 (163 Down, 412 Up) and 425 (132 Down, 293 Up) transcripts were affected for 0.05, 0.5, 1.4, 11 and 32 Gy, respectively. A total of 130 transcripts were altered in all groups (40 Down, 46 Up). For apoptosis, 36, 56, 11, 17 and 10 transcripts were differently regulated for 0.05, 0.5, 1.4, 11 and 32 Gy, respectively. Overall, 20, 23, 26, 21 and 14 biological processes were affected for 0.05, 0.5, 1.4, 11 and 32 Gy, respectively. Of these, only 2 were shared by all irradiated groups. Many similarities were obtained between 0.05 and 0.5 Gy and between 11 and 32 Gy, while the effects at 1.4 Gy deviated more from the other groups. Conclusively, high absorbed doses that mediate larger DNA damages altered genes involved in cytoskeleton reorganization. In contrast, low doses which produce few DNA damages altered more genes involved in cellular maintenance and metabolism. Interestingly, there seemed to be a transition phase around 1.4 Gy in the type of cellular response to DNA damages. Further work is needed in order to gain a complete understanding of the processes involved. (authors)

  10. Transgenerational developmental effects and genomic instability after X-irradiation of preimplantation embryos: Studies on two mouse strains

    International Nuclear Information System (INIS)

    Jacquet, P.; Buset, J.; Neefs, M.; Vankerkom, J.; Benotmane, M.A.; Derradji, H.; Hildebrandt, G.; Baatout, S.

    2010-01-01

    Recent results have shown that irradiation of a single cell, the zygote or 1-cell embryo of various mouse strains, could lead to congenital anomalies in the fetuses. In the Heiligenberger strain, a link between the radiation-induced congenital anomalies and the development of a genomic instability was also suggested. Moreover, further studies showed that in that strain, both congenital anomalies and genomic instability could be transmitted to the next generation. The aim of the experiments described in this paper was to investigate whether such non-targeted transgenerational effects could also be observed in two other radiosensitive mouse strains (CF1 and ICR), using lower radiation doses. Irradiation of the CF1 and ICR female zygotes with 0.2 or 0.4 Gy did not result in a decrease of their fertility after birth, when they had reached sexual maturity. Moreover, females of both strains that had been X-irradiated with 0.2 Gy exhibited higher rates of pregnancy, less resorptions and more living fetuses. Additionally, the mean weight of living fetuses in these groups had significantly increased. Exencephaly and dwarfism were observed in CF1 fetuses issued from control and X-irradiated females. In the control group of that strain, polydactyly and limb deformity were also found. The yields of abnormal fetuses did not differ significantly between the control and X-irradiated groups. Polydactyly, exencephaly and dwarfism were observed in fetuses issued from ICR control females. In addition to these anomalies, gastroschisis, curly tail and open eye were observed at low frequencies in ICR fetuses issued from X-irradiated females. Again, the frequencies of abnormal fetuses found in the different groups did not differ significantly. In both CF1 and ICR mouse strains, irradiation of female zygotes did not result in the development of a genomic instability in the next generation embryos. Overall, our results suggest that, at the moderate doses used, developmental defects

  11. Transgenerational developmental effects and genomic instability after X-irradiation of preimplantation embryos: Studies on two mouse strains

    Energy Technology Data Exchange (ETDEWEB)

    Jacquet, P., E-mail: pjacquet@sckcen.be [Molecular and Cellular Biology, Institute for Environment, Health and Safety, SCK.CEN, Boeretang 200, B-2400 Mol (Belgium); Buset, J.; Neefs, M. [Molecular and Cellular Biology, Institute for Environment, Health and Safety, SCK.CEN, Boeretang 200, B-2400 Mol (Belgium); Vankerkom, J. [Division of Environmental Research, VITO, Boeretang 200, B-2400 Mol (Belgium); Benotmane, M.A.; Derradji, H. [Molecular and Cellular Biology, Institute for Environment, Health and Safety, SCK.CEN, Boeretang 200, B-2400 Mol (Belgium); Hildebrandt, G. [Department of Radiotherapy and Radiation Oncology, University of Leipzig, Stephanstrasse 9a, D-04103 Leipzig (Germany); Department of Radiotherapy, University of Rostock, Suedring 75, D-18059 Rostock (Germany); Baatout, S. [Molecular and Cellular Biology, Institute for Environment, Health and Safety, SCK.CEN, Boeretang 200, B-2400 Mol (Belgium)

    2010-05-01

    Recent results have shown that irradiation of a single cell, the zygote or 1-cell embryo of various mouse strains, could lead to congenital anomalies in the fetuses. In the Heiligenberger strain, a link between the radiation-induced congenital anomalies and the development of a genomic instability was also suggested. Moreover, further studies showed that in that strain, both congenital anomalies and genomic instability could be transmitted to the next generation. The aim of the experiments described in this paper was to investigate whether such non-targeted transgenerational effects could also be observed in two other radiosensitive mouse strains (CF1 and ICR), using lower radiation doses. Irradiation of the CF1 and ICR female zygotes with 0.2 or 0.4 Gy did not result in a decrease of their fertility after birth, when they had reached sexual maturity. Moreover, females of both strains that had been X-irradiated with 0.2 Gy exhibited higher rates of pregnancy, less resorptions and more living fetuses. Additionally, the mean weight of living fetuses in these groups had significantly increased. Exencephaly and dwarfism were observed in CF1 fetuses issued from control and X-irradiated females. In the control group of that strain, polydactyly and limb deformity were also found. The yields of abnormal fetuses did not differ significantly between the control and X-irradiated groups. Polydactyly, exencephaly and dwarfism were observed in fetuses issued from ICR control females. In addition to these anomalies, gastroschisis, curly tail and open eye were observed at low frequencies in ICR fetuses issued from X-irradiated females. Again, the frequencies of abnormal fetuses found in the different groups did not differ significantly. In both CF1 and ICR mouse strains, irradiation of female zygotes did not result in the development of a genomic instability in the next generation embryos. Overall, our results suggest that, at the moderate doses used, developmental defects

  12. Studies of early effects of ultraviolet B irradiation on hairless mouse epidermis

    International Nuclear Information System (INIS)

    Olsen, W.M.

    1990-01-01

    The present study describes various early biochemical and cell kinetic aspects of the acute response of hairless epidermis with irradiation of narrow-banded wavelengths in the ultraviolet B region of the spectrum (280-320 nm), and their possible relationship to ultraviolet carcinogenicity. In vivo exposure of hairless mouse skin to a single dose of various narrow-banded wavelengths of ultraviolet B light demonstrated that 280, 290, 297 and 302 nm had a carcinogenic potency according to the tetrazolium test. No induction of DT-diaphorase was observed, which may signify that the actions of ultraviolet B light and chemical skin carcinogens differ at the cellular level, even though the nuclear effect on DNA may in principle be the same, e.g. mutation events, activation or amplication of oncogens, inhibition of anti-oncogens, etc. The early epidermal cell kinetic after a biologically relevant dose of ultraviolet B irradiation at a wavelength of 297 nm could be divided into two periods: the initial inhibition in the uptake of tritiated thymidine and the mitotic rate were followed by a long-lasting depression in the DNA synthesis rate combined with rapid cell proliferation. This shows that the acute vascular response (erythema and edema) to ultraviolet B lights is also associated with epidermal perturbations similar to the carcinogen-associated delay in cell cycle passage seen after chemical skin carcinogens like 7,12-dimethylbenz(α)anthracene and methylnitrosourea, as well as to the regenerative proliferation observed after chemical skin irritants like cantharidin. 93 refs., 6 figs

  13. Effect of prenatal gamma irradiation on the different gestation days on mouse

    International Nuclear Information System (INIS)

    Baskar, R.; Uma Devi, P.

    1993-01-01

    Pregnant Swiss albino mice were given a single local (abdomen) exposure of 50 cGy gamma radiation on days 1.5 to 17.5 post coitus (p.c.). The animals were sacrificed on 18th day of gestation and the fetuses were dissected out and examined for mortality, growth retardation, sex ratio, changes in body weight and length, head length and width, brain weight and incidence of microphthalmia. Preimplantation exposures (days 1.5 and 3.5 p.c.) resulted in a significant increase in embryonic and fetal mortality, while exposure during the postimplantation period (days 5.5 to 12.5 p.c.) produced a significant increase in the number of growth retarded fetuses. A high incidence of growth retarded fetuses was also observed by irradiation at the late fetal period (17.5 days p.c.). Brain weight was significantly affected by exposure on some days during all the three phases of development, i.e. preimplantation (3.5 days p.c.), mager organogenesis (9.5 to 12.5 days p.c.) and fetal (14.5 and 17.5 days p.c.) periods, though the period of sensitiveness was larger during organogenesis period. Eye development was sensitive to radiation effect mainly during the late organogenesis (9.5 to 12.5 days p.c.). It is concluded that the radiosensitivity of mouse embryos to radiation lethality at low dose is confirmed to the preimplantation period, while growth retardation is a prominent effect of irradiation at the early postimplantation embryos. The late organogenesis, especially from 9.5 to 12.5 days p.c. appears to be a particularly sensitive period in the development of brain and eye, though the sensitivity of brain may continue during the fetal life. (author). 9 refs

  14. Electronmicroscopic study of gamma irradiated mouse spleen during primary immune response

    International Nuclear Information System (INIS)

    Burneva, V.G.; Gitsov, L.G.; Boyadzhieva-Mikhajlova, A.; Kyncheva, L.S.; Viklichka, St.

    1978-01-01

    An electronmicroscopic study of the mouse spleen immunocompetent cells during the productive phase of the primary immune response after sublethal gamma ray irradiation is carried out. For this purpose the animals were immunized with sheep red blood cells 24 hours after irradiation and sacrified on the 5th day after immunization. The number of small lymphocytes is reduced in all zones of the spleen. Only in the periarteriolar area the lymphoid sheaths are well outlines and the ultrastructure of the cells preserved. Three types of reticulohistocytic elements, according to their radiosensitivity are observed. The most radioresistant cells are the fixed ''dark'' reticular cells which do not complete phagocytosis. The ultrastructure of their nucleus and cytoplasm is not damaged. The macrophages are also quite resistant. The ''light'' reticular cells are the most radiosensitive. The chromatine of their nuclei is dispersed. The mitochondria are imbibed, with a reduced number of cristae. The cytoplasm contains many electron light vesicles, different in size. The changes in the processes of the dendridic cells in the spleen lymph follicles are of particular interest. Compared with the control animals the processes of dendritic reticular cells are markedly reduced. The postirradiation ultrastructural changes of the spleen cells indicate that parallel with the basic factor (the death of a considerable part of the small lymphocytes, precursors of the antibody-synthetizing cells) the reduced antibody-formation is due also to the limited capacity for ''traping'' the antigen on the processes of the dendritic follicular cells and to the reduced capacity of the reticulo-histocytic cells for antigen phagocytosis. The later is determined both by the damage of a considerable part of the phagocytes (radiosensitive ''light'' reticulo-histocytic cells) and by the blocking of the functionally undamaged phagocytes from ingested debris. (K.M.)

  15. Acute Radiation Syndrome Severity Score System in Mouse Total-Body Irradiation Model.

    Science.gov (United States)

    Ossetrova, Natalia I; Ney, Patrick H; Condliffe, Donald P; Krasnopolsky, Katya; Hieber, Kevin P

    2016-08-01

    Radiation accidents or terrorist attacks can result in serious consequences for the civilian population and for military personnel responding to such emergencies. The early medical management situation requires quantitative indications for early initiation of cytokine therapy in individuals exposed to life-threatening radiation doses and effective triage tools for first responders in mass-casualty radiological incidents. Previously established animal (Mus musculus, Macaca mulatta) total-body irradiation (γ-exposure) models have evaluated a panel of radiation-responsive proteins that, together with peripheral blood cell counts, create a multiparametic dose-predictive algorithm with a threshold for detection of ~1 Gy from 1 to 7 d after exposure as well as demonstrate the acute radiation syndrome severity score systems created similar to the Medical Treatment Protocols for Radiation Accident Victims developed by Fliedner and colleagues. The authors present a further demonstration of the acute radiation sickness severity score system in a mouse (CD2F1, males) TBI model (1-14 Gy, Co γ-rays at 0.6 Gy min) based on multiple biodosimetric endpoints. This includes the acute radiation sickness severity Observational Grading System, survival rate, weight changes, temperature, peripheral blood cell counts and radiation-responsive protein expression profile: Flt-3 ligand, interleukin 6, granulocyte-colony stimulating factor, thrombopoietin, erythropoietin, and serum amyloid A. Results show that use of the multiple-parameter severity score system facilitates identification of animals requiring enhanced monitoring after irradiation and that proteomics are a complementary approach to conventional biodosimetry for early assessment of radiation exposure, enhancing accuracy and discrimination index for acute radiation sickness response categories and early prediction of outcome.

  16. Chimera states in mechanical oscillator networks

    DEFF Research Database (Denmark)

    Martens, Erik Andreas; Thutupalli, Shashi; Fourrière, Antoine

    2013-01-01

    of identical oscillators, numerous theoretical studies in recent years have revealed the intriguing possibility of "chimera states," in which the symmetry of the oscillator population is broken into a synchronous part and an asynchronous part. However, a striking lack of empirical evidence raises the question...... of whether chimeras are indeed characteristic of natural systems. This calls for a palpable realization of chimera states without any fine-tuning, from which physical mechanisms underlying their emergence can be uncovered. Here, we devise a simple experiment with mechanical oscillators coupled...... in a hierarchical network to show that chimeras emerge naturally from a competition between two antagonistic synchronization patterns. We identify a wide spectrum of complex states, encompassing and extending the set of previously described chimeras. Our mathematical model shows that the self-organization observed...

  17. Technical Note: Immunohistochemical evaluation of mouse brain irradiation targeting accuracy with 3D-printed immobilization device

    Energy Technology Data Exchange (ETDEWEB)

    Zarghami, Niloufar, E-mail: nzargham@uwo.ca; Jensen, Michael D. [Department of Medical Biophysics, The University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 3K7 (Canada); Talluri, Srikanth; Dick, Frederick A. [Department of Biochemistry, The University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 3K7 (Canada); London Regional Cancer Program, London Health Sciences Centre, 800 Commissioners Road East, London, Ontario N6A 5W9 (Canada); Foster, Paula J. [Imaging Research Laboratories, Robarts Research Institute, 100 Perth Drive, London, Ontario N6A 5K8 (Canada); Department of Medical Biophysics, The University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 3K7 (Canada); Chambers, Ann F. [Department of Medical Biophysics, The University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 3K7 (Canada); Department of Oncology, The University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 3K7 (Canada); London Regional Cancer Program, London Health Sciences Centre, 800 Commissioners Road East, London, Ontario N6A 5W9 (Canada); Wong, Eugene [Department of Physics and Astronomy, The University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 3K7 (Canada); Department of Medical Biophysics, The University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 3K7 (Canada); Department of Oncology, The University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 3K7 (Canada); London Regional Cancer Program, London Health Sciences Centre, 800 Commissioners Road East, London, Ontario N6A 5W9 (Canada)

    2015-11-15

    Purpose: Small animal immobilization devices facilitate positioning of animals for reproducible imaging and accurate focal radiation therapy. In this study, the authors demonstrate the use of three-dimensional (3D) printing technology to fabricate a custom-designed mouse head restraint. The authors evaluate the accuracy of this device for the purpose of mouse brain irradiation. Methods: A mouse head holder was designed for a microCT couch using CAD software and printed in an acrylic based material. Ten mice received half-brain radiation while positioned in the 3D-printed head holder. Animal placement was achieved using on-board image guidance and computerized asymmetric collimators. To evaluate the precision of beam localization for half-brain irradiation, mice were sacrificed approximately 30 min after treatment and brain sections were stained for γ-H2AX, a marker for DNA breaks. The distance and angle of the γ-H2AX radiation beam border to longitudinal fissure were measured on histological samples. Animals were monitored for any possible trauma from the device. Results: Visualization of the radiation beam on ex vivo brain sections with γ-H2AX immunohistochemical staining showed a sharp radiation field within the tissue. Measurements showed a mean irradiation targeting error of 0.14 ± 0.09 mm (standard deviation). Rotation between the beam axis and mouse head was 1.2° ± 1.0° (standard deviation). The immobilization device was easily adjusted to accommodate different sizes of mice. No signs of trauma to the mice were observed from the use of tooth block and ear bars. Conclusions: The authors designed and built a novel 3D-printed mouse head holder with many desired features for accurate and reproducible radiation targeting. The 3D printing technology was found to be practical and economical for producing a small animal imaging and radiation restraint device and allows for customization for study specific needs.

  18. Technical Note: Immunohistochemical evaluation of mouse brain irradiation targeting accuracy with 3D-printed immobilization device

    International Nuclear Information System (INIS)

    Zarghami, Niloufar; Jensen, Michael D.; Talluri, Srikanth; Dick, Frederick A.; Foster, Paula J.; Chambers, Ann F.; Wong, Eugene

    2015-01-01

    Purpose: Small animal immobilization devices facilitate positioning of animals for reproducible imaging and accurate focal radiation therapy. In this study, the authors demonstrate the use of three-dimensional (3D) printing technology to fabricate a custom-designed mouse head restraint. The authors evaluate the accuracy of this device for the purpose of mouse brain irradiation. Methods: A mouse head holder was designed for a microCT couch using CAD software and printed in an acrylic based material. Ten mice received half-brain radiation while positioned in the 3D-printed head holder. Animal placement was achieved using on-board image guidance and computerized asymmetric collimators. To evaluate the precision of beam localization for half-brain irradiation, mice were sacrificed approximately 30 min after treatment and brain sections were stained for γ-H2AX, a marker for DNA breaks. The distance and angle of the γ-H2AX radiation beam border to longitudinal fissure were measured on histological samples. Animals were monitored for any possible trauma from the device. Results: Visualization of the radiation beam on ex vivo brain sections with γ-H2AX immunohistochemical staining showed a sharp radiation field within the tissue. Measurements showed a mean irradiation targeting error of 0.14 ± 0.09 mm (standard deviation). Rotation between the beam axis and mouse head was 1.2° ± 1.0° (standard deviation). The immobilization device was easily adjusted to accommodate different sizes of mice. No signs of trauma to the mice were observed from the use of tooth block and ear bars. Conclusions: The authors designed and built a novel 3D-printed mouse head holder with many desired features for accurate and reproducible radiation targeting. The 3D printing technology was found to be practical and economical for producing a small animal imaging and radiation restraint device and allows for customization for study specific needs

  19. Induction of micronuclei in human and mouse lymphocytes irradiated with gamma radiation and effect of panax ginseng C. A. Meyer

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sung Ho; Oh, Heon; Lee, Song Eun [Chonnam National Univ., Kwangju (Korea, Republic of); Lee, Yun Sil; Kim, Tae Hwan [Korea Cancer Center Hospital, Seoul (Korea, Republic of); Jeong, Kyu Sik [Korea Research Institute of Bioscience and Biotechnology, Taejon (Korea, Republic of); Ryu, Si Yun [Chungnam National Univ., Taejon (Korea, Republic of)

    1997-09-01

    The frequencies of {gamma}-ray-induced micronuclei (MN) in Cytokinesis-Blocked (CB) lymphocytes at several doses were measured in three donors of human and C57BL/6 mice. Measurements performed after irradiation showed a dose-related increases in MN frequency in each of the donors studied. The relative sensitivity of mouse in Spleen Lymphocytes (SLs) compared with human Peripheral Blood Lymphocytes (PBLs) was estimated by best fitting linear-quadratic model based on the radiation-induced MN data over the range from 0 cGy to 400 cGy. In the case of MN frequency with 0.2 per CB cell, the relative sensitivity of mouse SLs was 1.67. Compared with the radiation-induced MN formation in the PBLs of human, the SLs of mouse were more radiosensitive. Using this MN assay with human PBLs and mouse SLs, studies were performed to determine whether the water fraction of ginseng (Panax ginseng C.A.Meyer)against radiation-induced MN in human PBLs after in vitro irradiation (3Gy) and in SLs of C57BL/6 mice after in vivo irradiation (3Gy). The frequency of MN in human PBLs was reduced by water fraction of ginseng (0.5mg/ml of medium) both pre-and post treatment (p<0.01) in vitro. In addition, the frequency of MN in mouse SLs was also reduced by pretreatment of ginseng (2mg/ml of drinking water for 7 days) in vivo.

  20. In situ PCR detection and significance of IL-3 gene expression in irradiated hematopoietic cells of mouse bone marrow

    International Nuclear Information System (INIS)

    Peng Ruiyun; Wang Dewen; Xiong Chengqi; Gao Yabing; Li Yanping; Yang Hong; Cui Yufang

    2000-01-01

    Objective: To study the significance of endogenous interleukin 3(IL-3) gene expression in repair of irradiated mouse bone marrow. Methods: Seventy-eight LACA mice were subjected to total body irradiation with 60 Co γ-rays and were sacrificed within 4 weeks after irradiation. The bone marrow histopathological sections were stained with HE, and the expression of endogenous IL-3 gene was detected by means of immunocytochemistry,in situ hybridization(ISH) and in situ reverse transcription PCR(IS RT-PCR). Results: Obvious injury of bone marrow occurred after irradiation and then recovered within 4 weeks. IL-3 protein was obviously increased in the cytoplasm of recovering hematopoietic cells(HCs), especially on day 21 after irradiation, while its mRNA was poorly positive by ISH on days 10-21, especially day 15.IS RT-PCR showed that IL-3 mRNA was strongly positive in recovering HCs cytoplasm, especially on days 10 to 15. Conclusion: In situ RT-PCR can objectively reflect the regulation of IL-3 gene expression in bone marrow after irradiation, and the expression of endogenous IL-3 gene may play an important role in hematopoietic reconstruction of irradiated bone marrow

  1. T cell progenitors in the mouse fetal liver

    International Nuclear Information System (INIS)

    Rabinowich, H.; Umiel, T.; Globerson, A.

    1983-01-01

    Fourteen-day mouse fetal liver was found to contain cells capable of giving rise to T as well as B cell functions. The experimental system consisted of congenic C3H/DiSn and (C3H/DiSn X C3H.SW)F1 lethally irradiated (900 R) mice reconstituted with C3H/DiSn fetal liver or bone marrow cells. Assays included thyroid allograft rejection as well as in vitro measurement of reactivity to phytohemagglutinin (PHA) and concanavalin A (Con A) and in a mixed lymphocyte culture (MLC) system in spleen, lymph node, and thymus cells. The fetal liver chimeras were found to become as capable as the bone marrow chimeras in responding in these various assays. The T cell responses lagged behind the responses to the B cell mitogens dextran sulfate (DXS) and lipopolysaccharide (LPS) (30 days after reconstitution, as compared with 14 days for DXS and 21 for LPS). The reacting cells were of the donor genotype, as revealed after treatment with C3H/DiSn (H-2k) anti-C3H.SW (H-2b) congenic sera. T cell responses were not manifest in thymectomized (TX) chimeras. Hence, the liver seems to contain cells capable of developing into T cell lineages in a thymus-dependent process

  2. Growth promotion of genetically modified hematopoietic progenitors using an antibody/c-Mpl chimera.

    Science.gov (United States)

    Kawahara, Masahiro; Chen, Jianhong; Sogo, Takahiro; Teng, Jinying; Otsu, Makoto; Onodera, Masafumi; Nakauchi, Hiromitsu; Ueda, Hiroshi; Nagamune, Teruyuki

    2011-09-01

    Thrombopoietin is a potent cytokine that exerts proliferation of hematopoietic stem cells (HSCs) through its cognate receptor, c-Mpl. Therefore, mimicry of c-Mpl signaling by a receptor recognizing an artificial ligand would be attractive to attain specific expansion of genetically modified HSCs. Here we propose a system enabling selective expansion of genetically modified cells using an antibody/receptor chimera that can be activated by a specific antigen. We constructed an antibody/c-Mpl chimera, in which single-chain Fv (ScFv) of an anti-fluorescein antibody was tethered to the extracellular D2 domain of the erythropoietin receptor and transmembrane/cytoplasmic domains of c-Mpl. When the chimera was expressed in interleukin (IL)-3-dependent pro-B cell line Ba/F3, genetically modified cells were selectively expanded in the presence of fluorescein-conjugated BSA (BSA-FL) as a specific antigen. Furthermore, highly purified mouse HSCs transduced with the retrovirus carrying antibody/c-Mpl chimera gene proliferated in vitro in response to BSA-FL, and the cells retained in vivo long-term repopulating abilities. These results demonstrate that the antibody/c-Mpl chimera is capable of signal transduction that mimics wild-type c-Mpl signaling. Copyright © 2011 Elsevier Ltd. All rights reserved.

  3. Excision of pyrimidine dimers from epidermal DNA and nonsemiconservative epidermal DNA synthesis following ultraviolet irradiation of mouse skin

    International Nuclear Information System (INIS)

    Bowden, G.T.; Trosko, J.E.; Shapas, B.G.; Boutwell, R.K.

    1975-01-01

    Pyrimidine dimer production and excision in epidermal DNA were studied at five different dose levels of ultraviolet light in the skin of intact mice. Dimer production increased with dose up to 50,400 ergs/sq mm. Approximately 30 percent of the thymine-containing dimers were excised by 24 hr after irradiation at three lower dose levels of ultraviolet light. Nonsemiconservative DNA replication in ultraviolet-irradiated mouse skin was shown to continue for at least 18 hr. The rate of nonsemiconservative replication decreased with time, but did so slowly. The initial rates of nonsemiconservative replication increased with ultraviolet light dose levels up to about 4200 ergs/sq mm, after which the initial rates were decreased. Semiconservative epidermal DNA synthesis was shown to be inhibited by hydroxyurea, but hydroxyurea had no effect on ultraviolet light-induced nonsemiconservative DNA replication. The observed pyrimidine dimer excision and nonsemiconservative DNA replication suggest that in the intact mouse the cells of the epidermis are capable of DNA excision repair after ultraviolet irradiation of mouse skin

  4. In vitro induction of mutation and separation of chimeras in Gerbera jamesonii

    International Nuclear Information System (INIS)

    Jerzy, M.; Zalewska, M.; Garczewska, A.

    1994-01-01

    Using ex vitro leaves as objects to be irradiated and to induce variation in sixteen Gerbera jamesonii cultivars, reproduced from adventitious buds, resulted in obtaining the mutants which inflorescence color was uniformly changed and which newly acquired traits recurred in the second generation of plants reproduced vegetatively from the isolated shoot tips. However, chimeras appeared among the vM 1 plants exposed to various doses of gamma rays (5-25 Gy and they constituted almost half of the mutated plants. A further propagation of chimeras from leaf explants forming adventitious shoots significantly increased the number of solid mutants with uniformly changed inflorescence color in the vM 1 generation. (author)

  5. Secondary Disease in Radiation Chimeras

    Energy Technology Data Exchange (ETDEWEB)

    Congdon, C. C. [Biology Division, Oak Ridge National Laboratory, Oak Ridge, TN (United States)

    1969-07-15

    A review of research dealing directly or indirectly with the development of bidirectional tolerance in radiation chimeras has been made, emphasizing some of the contemporary research on this subject in Oak Ridge and Knoxville. By controlling such factors as cell dose, age of donor animal and day of cell injection, it was possible to achieve bidirectional tolerance. Attempts to reduce bidirectional tolerance in favour of increasing the graft-versus-host reaction were less successful. Hypoxic caging demonstrated a new approach to achieving bidirectional tolerance through physiological competition for growth. Graft-versus-host reactions have a lower growth priority than marrow regeneration or erythropoietic hyperplasia. Study of pathologic processes, immunologic capability and the-biochemical lesions in radiation chimeras all lead to new ideas that involve bidirectional tolerance. The investigations on dose rate in radiation suppression of the immune response and on LD{sub 50} (30- to 90-day)values after injection of different numbers of marrow cells all have a bearing on control of the host-versus-graft response and therefore are important in understanding bidirectional tolerance. (author)

  6. Refining the intrinsic chimera flap: a review.

    Science.gov (United States)

    Agarwal, Jayant P; Agarwal, Shailesh; Adler, Neta; Gottlieb, Lawrence J

    2009-10-01

    Reconstruction of complex tissue deficiencies in which each missing component is in a different spatial relationship to each other can be particularly challenging, especially in patients with limited recipient vessels. The chimera flap design is uniquely suited to reconstruct these deformities. Chimera flaps have been previously defined in many ways with 2 main categories: prefabricated or intrinsic. Herein we attempt to clarify the definition of a true intrinsic chimeric flap and provide examples of how these constructs provide a method for reconstruction of complex defects. The versatility of the intrinsic chimera flap and its procurement from 7 different vascular systems is described. A clarification of the definition of a true intrinsic chimera flap is described. In addition, construction of flaps from the lateral femoral circumflex, deep circumflex iliac, inferior gluteal, peroneal, subscapular, thoracodorsal, and radial arterial systems is described to showcase the versatility of these chimera flaps. A true intrinsic chimera flap must consist of more than a single tissue type. Each of the tissue components receives its blood flow from separate vascular branches or perforators that are connected to a single vascular source. These vascular branches must be of appropriate length to allow for insetting with 3-dimensional spatial freedom. There are a multitude of sites from which true intrinsic chimera flaps may be harvested.

  7. Effects of whole-body and partial-body x irradiation upon epidermal mitotic activity during wound healing in mouse skin

    International Nuclear Information System (INIS)

    Kobayashi, K.

    1977-01-01

    Mitotic activity of normal (unwounded) and wounded skin was measured in the control (nonirradiated) and whole-body or partial-body x-irradiated mouse. Higher mitotic activity in the anterior than in the posterior region of the body was found in both the normal and the wounded skin of the control mouse. Whole-body irradiation (500 R) depressed completely the mitotic activity of normal skin 2 to 4 days after irradiation. In spite of this depression in mitotic activity, a surgical incision made 1 to 3 days after irradiation could induce a burst of proliferation after an inhibition of an initial mitosis increase. When the animals were partially irradiated with 500 R 3 days before wounding, it was shown that mitosis at 24 hr after wounding was inhibited markedly by the local effect of irradiation and that mitosis also could be inhibited diversely by the abscopal effect of irradiation. Because of a close similarity of sequential mitotic patterns between whole-body-irradiated and flapped-skin-only-irradiated groups (direct irradiation), the effect of irradiation upon mitosis was considered to be primarily local. Some discussions were made concerning the possible reasons which made a difference in mitotic patterns between the head-only-irradiated group, the irradiated group including the head and other parts of the body except for the skin flap

  8. Proliferative kinetics of the haematopoietic stem cells of the mouse after several weeks of reconvalescence of an irradiation attack

    International Nuclear Information System (INIS)

    Huebner, G.

    1980-01-01

    The 125 IDU(iodo-deoxyuridine) tracer-technique was applied for investigating proliferative kinetics. The intention was to reveal a possible persistent irradiation damage in the haematopoietic stem-cells of the mouse. The three following methodically differing arrangements were made: 1. 35 days after irradiation with 450 rad no difference is found between the measured turnover of incorporated 125 IUD in the bone marrow and not irradiated mice. However, there is a splenic cell population which unambiguously transfers its activity slowlier. A dose-response relationship exists to a limited extent. 2. By four transplantations at different instants the donors were marked first, and then the turnover of the early haematopoietic precursor cells in the bone marrow was detected. It resulted that 35 days after irradiation with 450 rad the turnover takes place slightly slowlier than in not irradiated early precursor cells. Iodised water, which is administered before the tracer technique is applied, seems to have a stimulating effect, particularly on the turnover of irradiated stem cells; the marking with a specific activity of 2000 Ci/mol seems to have a slightly toxic effect. 3. A test was developed, by which the proliferation velocity of stem cells and their descendants is measured when there is a very high proliferation stimulus. Differing amounts of bone marrow cells are transfused to lethally irradiated receivers. Within the logarithmic phase of the 125 IDU incorporation the relative cellular proliferation, originating in the stem cells being in the spleen, is determined for the interval between day 3 and day 5. It results very clearly that the descendants of those stem cells irradiated with 450 rad after a reconvalescence time of 35 days present a lower degree of rapid proliferative ability than the not irradiated cells. (orig./MG) [de

  9. Solvable model for chimera states of coupled oscillators.

    Science.gov (United States)

    Abrams, Daniel M; Mirollo, Rennie; Strogatz, Steven H; Wiley, Daniel A

    2008-08-22

    Networks of identical, symmetrically coupled oscillators can spontaneously split into synchronized and desynchronized subpopulations. Such chimera states were discovered in 2002, but are not well understood theoretically. Here we obtain the first exact results about the stability, dynamics, and bifurcations of chimera states by analyzing a minimal model consisting of two interacting populations of oscillators. Along with a completely synchronous state, the system displays stable chimeras, breathing chimeras, and saddle-node, Hopf, and homoclinic bifurcations of chimeras.

  10. The Dependence of Chimera States on Initial Conditions

    International Nuclear Information System (INIS)

    Feng Yue-E; Li Hai-Hong

    2015-01-01

    A chimera state consisting of both coherent and incoherent groups is a fascinating spatial pattern in non-locally coupled identical oscillators. It is thought that random initial conditions hardly evolve to chimera states. In this work, we study the dependence of chimera states on initial conditions. We show that random initial conditions may lead to chimera states and the chance of realizing chimera states becomes increasing when the model parameters are moving away from the boundary of their stable regime. (paper)

  11. Stromal damage in the mouse small intestine after Co60 gamma or D-T neutron irradiation

    International Nuclear Information System (INIS)

    Carr, K.E.; Hamlet, R.; Nias, A.H.; Boyle, F.C.; Fife, M.G.

    1985-01-01

    Stromal constituents have been examined in mouse small intestine 3 1/2 days after irradiation with either 18-20 Gy gamma rays or 10 Gy neutrons. These doses were chosen for their equivalent effect on the number of intestinal crypts found after treatment. Despite the fact that the topography of the villi, as imaged by scanning electron microscopy, was altered by treatment, with gamma irradiated villi showing lateral or horizontal collapse while neutron irradiation produced conical villi, few changes were seen in the villous stromal compartments. There were, however, ultrastructural changes observed in the stroma of the pericryptal plate. Changes common to both radiation schedules included disorganisation of the subepithelial stroma and an increase in the number of irregular processes. Some changes after irradiation, however, were not identical in the two groups. Gamma irradiation resulted in pale, foamy cytoplasmic vesicles, the separation of smooth muscle cells and changes in the structure of the luminal aspect of arterial blood vessels while neutron irradiation produced dense cytoplasmic vesicles and electron dense bodies within the substance of peripheral nerve twigs. The fact that the variation in the topography of villi after the two types of radiation is matched by changes in the deep stroma rather than within the villi themselves indicates that the stromal pericryptal plate is of importance in the structure of the villus and the extent to which the villi have varied from the normal finger shaped structure

  12. Decreased weight, DNA, RNA and protein content of the brain after neutron irradiation of the 18-day mouse embryo

    International Nuclear Information System (INIS)

    Antal, S.; Fonagy, A.; Hidvegi, E.J.; Fueloep, Z.; Vogel, H.H. Jr.

    1984-01-01

    Pregnant mice were irradiated with 0.5 Gy fission neutrons on the eighteenth day of gestation. Average litter size at birth was unchanged but mortality increased 5-6 fold in the first 3 days. Irradiated mice were the same weight as control mice at birth but showed a progressively increasing weight deficiency up to at least 36 days compared to controls. Brain weight was 37, 45 and 25% less in 2-, 3- and 52-week old irradiated animals; the ratio of brain weight to body weight was 25, 27 and 13% less. The concentrations of DNA, RNA and protein (mg/g wet tissue) were the same in irradiated and control mice in brain and liver at all three ages. Total DNA, RNA and protein contents of whole brain after irradiation were 56-75% of control levels. No definite decrease was observed in liver. Histological study at 6 hours after irradiation showed nuclear pyknosis in the central nervous system from definite to very severe according to the part examined. It is concluded that damage to the central nervous system of the 18-day mouse foetus is mainly due to killing and/or inhibition of the differentiation of neuroblasts. (author)

  13. Synthesis of periclinal chimera in cassava.

    Science.gov (United States)

    Nassar, N M A; Bomfim, N

    2013-02-27

    We provide the first report on the synthesis of a very productive interspecific periclinal chimera of cassava, with large and edible roots. The epidermal tissue of the chimera was formed by the cultivated species Manihot esculenta (E), and the subepidermis and internal tissue were formed by the wild species, Manihot fortalezensis (F). We used cytogenetics and morphological analyses to determine the origins of all tissues. These results may offer potential for the development of new lines for crop improvement based on the use of chimera composed of different combinations of wild species and cultivars.

  14. Gene Expression Changes in Mouse Intestinal Tissue Following Whole-Body Proton or Gamma-Irradiation

    Science.gov (United States)

    Purgason, Ashley; Zhang, Ye; Mangala, Lingegowda; Nie, Ying; Gridley, Daila; Hamilton, Stanley R.; Seidel, Derek V.; Wu, Honglu

    2014-01-01

    Crew members face potential consequences following exposure to the space radiation environment including acute radiation syndrome and cancer. The space radiation environment is ample with protons, and numerous studies have been devoted to the understanding of the health consequences of proton exposures. In this project, C57BL/6 mice underwent whole-body exposure to 250 MeV of protons at doses of 0, 0.1, 0.5, 2 and 6 Gy and the gastrointestinal (GI) tract of each animal was dissected four hours post-irradiation. Standard H&E staining methods to screen for morphologic changes in the tissue showed an increase in apoptotic lesions for even the lowest dose of 0.1 Gy, and the percentage of apoptotic cells increased with increasing dose. Results of gene expression changes showed consistent up- or down- regulation, up to 10 fold, of a number of genes across exposure doses that may play a role in proton-induced oxidative stress including Gpx2. A separate study in C57BL/6 mice using the same four hour time point but whole-body gamma-irradiation showed damage to the small intestine with lesions appearing at the smallest dose of 0.05 Gy and increasing with increasing absorbed dose. Expressions of genes associated with oxidative stress processes were analyzed at four hours and twenty-four hours after exposure to gamma rays. We saw a much greater number of genes with significant up- or down-regulation twenty-four hours post-exposure as compared to the four hour time point. At both four hours and twenty-four hours post-exposure, Duox1 and Mpo underwent up-regulation for the highest dose of 6 Gy. Both protons and gamma rays lead to significant variation in gene expressions and these changes may provide insight into the mechanism of injury seen in the GI tract following radiation exposure. We have also completed experiments using a BALB/c mouse model undergoing whole-body exposure to protons. Doses of 0, 0.1, 1 and 2 Gy were used and results will be compared to the work mentioned

  15. PyChimera: use UCSF Chimera modules in any Python 2.7 project.

    Science.gov (United States)

    Rodríguez-Guerra Pedregal, Jaime; Maréchal, Jean-Didier

    2018-05-15

    UCSF Chimera is a powerful visualization tool remarkably present in the computational chemistry and structural biology communities. Built on a C++ core wrapped under a Python 2.7 environment, one could expect to easily import UCSF Chimera's arsenal of resources in custom scripts or software projects. Nonetheless, this is not readily possible if the script is not executed within UCSF Chimera due to the isolation of the platform. UCSF ChimeraX, successor to the original Chimera, partially solves the problem but yet major upgrades need to be undergone so that this updated version can offer all UCSF Chimera features. PyChimera has been developed to overcome these limitations and provide access to the UCSF Chimera codebase from any Python 2.7 interpreter, including interactive programming with tools like IPython and Jupyter Notebooks, making it easier to use with additional third-party software. PyChimera is LGPL-licensed and available at https://github.com/insilichem/pychimera. jaime.rodriguezguerra@uab.cat or jeandidier.marechal@uab.cat. Supplementary data are available at Bioinformatics online.

  16. Kinetics and capacity of repair of sublethal damage in mouse lip mucosa during fractionated irradiations

    International Nuclear Information System (INIS)

    Ang, K.K.; Xu, F.X.; Landuyt, W.; van der Schueren, E.

    1985-01-01

    The kinetics and capacity of repair of sublethal damage in mouse lip mucosa have been investigated. To assess the rate of repair 2 and 5 irradiations have been given with intervals ranging from 1 to 24 hours. It was found that the sublethal damage induced by a dose of approximately 10 Gy was fully recovered in approximately 4 hr. After a dose of 5-6 Gy, cellular repair was completed within 3 hr. The half time of repair (T1/2) was estimated to be approximately 72 min for 10 Gy and approximately 54 min for 5-6 Gy. Although these results suggest that the rate of repair is dependent on the fraction size, the possible influence of the amount of repair of sublethal radiation damage with the various fraction sizes used can not be ruled out. To evaluate the capacity of repair, a single dose, 2, 4 and 10 fractions have been given in a maximal overall time of 3 days in order to minimize the influence of repopulation. The slope of the isoeffective curve was 0.32 and the alpha/beta ratio was 8.5 Gy. This indicates that the capacity of cellular repair of lip mucosa is similar to those of other rapidly proliferating tissues but smaller than those of late responding tissues. The results of the present and other studies demonstrate that there are considerable differences in the repair characteristics between acutely and late responding tissues. These features have to be dealt with when fractionation schedules are markedly altered

  17. Chimeras

    OpenAIRE

    Huther, Constanze

    2009-01-01

    What types of human-animal interspecific entities are used in biomedical research? Is creating such entities morally wrong? And what do interspecifics tell us about the moral significance of species? This thesis offers an introduction to the field of human-animal interspecifics from a bioethical perspective, with a special focus on the question of speciesism.

  18. Generation of axolotl hematopoietic chimeras

    Directory of Open Access Journals (Sweden)

    David Lopez

    2015-02-01

    Full Text Available Wound repair is an extremely complex process that requires precise coordination between various cell types including immune cells.  Unfortunately, in mammals this usually results in scar formation instead of restoration of the original fully functional tissue, otherwise known as regeneration.  Various animal models like frogs and salamanders are currently being studied to determine the intracellular and intercellular pathways, controlled by gene expression, that elicit cell proliferation, differentiation, and migration of cells during regenerative healing.  Now, the necessary genetic tools to map regenerative pathways are becoming available for the axolotl salamander, thus allowing comparative studies between scarring and regeneration.  Here, we describe in detail three methods to produce axolotl hematopoietic cell-tagged chimeras for the study of hematopoiesis and regeneration.

  19. Intermittent chaotic chimeras for coupled rotators

    DEFF Research Database (Denmark)

    Olmi, Simona; Martens, Erik Andreas; Thutupalli, Shashi

    2015-01-01

    Two symmetrically coupled populations of N oscillators with inertia m display chaotic solutions with broken symmetry similar to experimental observations with mechanical pendulums. In particular, we report evidence of intermittent chaotic chimeras, where one population is synchronized and the other...

  20. Allogeneic radiation chimeras induced in SPF mice

    International Nuclear Information System (INIS)

    Sado, Toshihiko; Kamisaku, Hitoko

    1977-01-01

    During the past two decades much has been learned concerning the immunobiology of bone marrow chimeras induced in experimental animals as well as in man. However, from the basic as well as clinical points of view, there still remain many unsolved questions yet to be resolved. In this presentation, we discussed some of our recent results on the immunobiology of radiation chimeras induced in specific-pathogen-free (SPF) mice. These included the following: (a) contribution of graft versus host reaction (GVHR) as well non- GVHR mediated immunologic mechanism(s) to the expression of immunologic dysfunctions observed in allogeneic and certain semiallogeneic chimeras, (b) existence of immunoregulatory mechanism as a basis for the apparent lack of immunologic reactivity (tolerance) to the host- as well as to the donor-type alloantigens in situ in successful allogeneic bone marrow chimeras, and (c) the effect of microflora of the environment on the stability of such immunoregulatory mechanisms and its possible mechanism of action. (auth.)

  1. Quantum walk on a chimera graph

    Science.gov (United States)

    Xu, Shu; Sun, Xiangxiang; Wu, Jizhou; Zhang, Wei-Wei; Arshed, Nigum; Sanders, Barry C.

    2018-05-01

    We analyse a continuous-time quantum walk on a chimera graph, which is a graph of choice for designing quantum annealers, and we discover beautiful quantum walk features such as localization that starkly distinguishes classical from quantum behaviour. Motivated by technological thrusts, we study continuous-time quantum walk on enhanced variants of the chimera graph and on diminished chimera graph with a random removal of vertices. We explain the quantum walk by constructing a generating set for a suitable subgroup of graph isomorphisms and corresponding symmetry operators that commute with the quantum walk Hamiltonian; the Hamiltonian and these symmetry operators provide a complete set of labels for the spectrum and the stationary states. Our quantum walk characterization of the chimera graph and its variants yields valuable insights into graphs used for designing quantum-annealers.

  2. Effects of low-dose irradiation of X-rays on IUdR incorporation into mouse tissues

    International Nuclear Information System (INIS)

    Misonoh, J.; Ishii, K.; Yoshida, M.; Okumura, Y.; Kodama, S.

    1992-01-01

    It is well known that biological responses get smaller when a radiation dose gets lower, and it makes it difficult to detect them with significant differences from background levels. Therefore we know little about biological effects arisen from very low-dose radiation in mammals and mammalian cells. Feinendegen et al. detected a significant reduction of 125 I-UdR uptake in bone marrow cells at doses below 0.01 Gy. Using this extremely sensitive biological response, they also indicated that cells of mice irradiated twice with an interval of 4 hours did not show any reaction after the second irradiation. This meant that cells became radio-resistant after whole-body irradiation with low-doses. This phenomenon, an acquired radio-resistance after low-dose irradiation, is explained as an adaptive response to radiation , which is recently well documented in cytogenic studies. In order to confirm that whether it is common in the cell renewal systems, IUdR incorporation into mouse spleen and the other tissues were studied after whole-body irradiation. (author). 7 refs., 1 fig., 2 tabs

  3. Mechanism of donor to host tolerance in rat bone marrow chimeras

    International Nuclear Information System (INIS)

    Tutschka, P.; Schwerdtfeger, R.; Slavin, R.; Santos, G.

    1977-01-01

    Lewis rats were conditioned with cyclophosphamide and grafted with AgB incompatible bone marrow. They were examined 250 days after transplantation and demonstrated to be healthy complete chimeras. Marrow cells from these chimeras were infused into lethally irradiated ACI, Lewis and BN recipients. Graft-versus-host disease occurred only in the BN rats. Other chimeric rats were given no treatment, busulfan, CY, or total body irradiation prior to the infusion of normal ACI BM. GvHD occurred only in animals given CY or TBI. Normal Lewis rats were conditioned with TBI and given ACI BM. In addition, they received whole blood, irradiated blood, or serum from chimeric rats. GvHD developed in all animals except those given unirradiated chimeric blood. These studies suggest that suppressor cell populations, sensitive to immunosuppression, are likely the fundamental mechanism of recovery from GvHD

  4. Non-identical multiplexing promotes chimera states

    Science.gov (United States)

    Ghosh, Saptarshi; Zakharova, Anna; Jalan, Sarika

    2018-01-01

    We present the emergence of chimeras, a state referring to coexistence of partly coherent, partly incoherent dynamics in networks of identical oscillators, in a multiplex network consisting of two non-identical layers which are interconnected. We demonstrate that the parameter range displaying the chimera state in the homogeneous first layer of the multiplex networks can be tuned by changing the link density or connection architecture of the same nodes in the second layer. We focus on the impact of the interconnected second layer on the enlargement or shrinking of the coupling regime for which chimeras are displayed in the homogeneous first layer. We find that a denser homogeneous second layer promotes chimera in a sparse first layer, where chimeras do not occur in isolation. Furthermore, while a dense connection density is required for the second layer if it is homogeneous, this is not true if the second layer is inhomogeneous. We demonstrate that a sparse inhomogeneous second layer which is common in real-world complex systems can promote chimera states in a sparse homogeneous first layer.

  5. Enhancing UCSF Chimera through web services.

    Science.gov (United States)

    Huang, Conrad C; Meng, Elaine C; Morris, John H; Pettersen, Eric F; Ferrin, Thomas E

    2014-07-01

    Integrating access to web services with desktop applications allows for an expanded set of application features, including performing computationally intensive tasks and convenient searches of databases. We describe how we have enhanced UCSF Chimera (http://www.rbvi.ucsf.edu/chimera/), a program for the interactive visualization and analysis of molecular structures and related data, through the addition of several web services (http://www.rbvi.ucsf.edu/chimera/docs/webservices.html). By streamlining access to web services, including the entire job submission, monitoring and retrieval process, Chimera makes it simpler for users to focus on their science projects rather than data manipulation. Chimera uses Opal, a toolkit for wrapping scientific applications as web services, to provide scalable and transparent access to several popular software packages. We illustrate Chimera's use of web services with an example workflow that interleaves use of these services with interactive manipulation of molecular sequences and structures, and we provide an example Python program to demonstrate how easily Opal-based web services can be accessed from within an application. Web server availability: http://webservices.rbvi.ucsf.edu/opal2/dashboard?command=serviceList. © The Author(s) 2014. Published by Oxford University Press on behalf of Nucleic Acids Research.

  6. Organ dose conversion coefficients based on a voxel mouse model and MCNP code for external photon irradiation.

    Science.gov (United States)

    Zhang, Xiaomin; Xie, Xiangdong; Cheng, Jie; Ning, Jing; Yuan, Yong; Pan, Jie; Yang, Guoshan

    2012-01-01

    A set of conversion coefficients from kerma free-in-air to the organ absorbed dose for external photon beams from 10 keV to 10 MeV are presented based on a newly developed voxel mouse model, for the purpose of radiation effect evaluation. The voxel mouse model was developed from colour images of successive cryosections of a normal nude male mouse, in which 14 organs or tissues were segmented manually and filled with different colours, while each colour was tagged by a specific ID number for implementation of mouse model in Monte Carlo N-particle code (MCNP). Monte Carlo simulation with MCNP was carried out to obtain organ dose conversion coefficients for 22 external monoenergetic photon beams between 10 keV and 10 MeV under five different irradiation geometries conditions (left lateral, right lateral, dorsal-ventral, ventral-dorsal, and isotropic). Organ dose conversion coefficients were presented in tables and compared with the published data based on a rat model to investigate the effect of body size and weight on the organ dose. The calculated and comparison results show that the organ dose conversion coefficients varying the photon energy exhibits similar trend for most organs except for the bone and skin, and the organ dose is sensitive to body size and weight at a photon energy approximately <0.1 MeV.

  7. Alkaline phosphatase role in bone marrow and spleen hemopoietic cells recovery after mouse whole-body irradiation

    International Nuclear Information System (INIS)

    Al Mouhamad, K.; Al Sheikh, F.

    2013-04-01

    Hematopoietic tissue is consisted of two distinctly different tissues, the first part is the hematopoietic stem cells and the second tissue is a mixture of many supportive cells which the most important one of them is alkaline phosphatase (ALP)-secreted-fibroblastic cells (FBCs). It was thought that FBCs play an important role in the hematopoiesis through ALP secretion. Our previous studies indicated that the ALP secretion in bone marrow (BM) increased after a whole mouse body irradiation when the BM cellular component is completely destroyed and, then it was decreased when the BM regain its cellular component. We performed some experiences to verify if there is any role to the ALP in the hematopoiesis. We irradiated three groups of mice to non-lethal dose, the first one was injected by Tetramizole (anti-ALP) 24 hours before irradiation, and the second was injected by Lisinopril (anti-hematopoiesis) 24 hours before irradiation and the third left without any injection. The fourth left as control. Many histological sections were taken from BM and spleen on 1, 3, 7 and 30 days after irradiation to perform ALP-histological detection. These experiences were repeated to count BM cells. ALP secretion level in the BM was reached the maximum 3 days after irradiation without any injection when the cell number was in minimum then, the level of ALP start to decrease and the cell number start to increase. ALP secretion delayed when the mice were injected by Tetramizole and BM cell population also delayed to return to its normal position. But, the ALP secretion increased directly after irradiation when the mice were injected by Lisinopril which, the ALP secretion, normally reached the maximum by the third day. These results may indicate a role to the ALP in BM and spleen hematopoietic cell recovery (author).

  8. Effects of hyperthermia and X-irradiation on mouse stromal tissue

    NARCIS (Netherlands)

    Wondergem, J.; Begg, A. C.; Haveman, J.

    1986-01-01

    The sensitivity of normal stroma to heat, irradiation and heat combined with irradiation has been studied using the tumour bed effect (TBE) assay. Irradiation before implantation led to a TBE. This TBE was dose dependent below 15 Gy, the TBE remaining relatively constant above 15 Gy. The interval

  9. Effects of hyperthermia and X-irradiation on mouse stromal tissue

    International Nuclear Information System (INIS)

    Wondergem, J.; Haveman, J.

    1986-01-01

    The sensitivity of normal stroma to heat, irradiation and heat combined with irradiation, was studied using the tumour bed effect (TBE) assay. Irradiation before implantation led to a TBE, dose dependent below 15 Gy, but remaining relatively constant above. The interval (0-90 days) between irradiation and tumour implantation did not influence the magnitude of the TBE. Hyperthermia with large heat doses (45-60 min at 44 0 C) before implantation may lead to a TBE. The interval between hyperthermia and tumour implantation was very important. Results showed that the recovery from heat-induced stromal damage is very rapid. When the interval between hyperthermia and tumour implantation was 10 days or longer, no TBE could be observed. Irradiation combined with large heat doses (30-60 min at 44 0 C) decreased the radiation-induced TBE. The combination of irradiation with mild heat treatments (15 min at 44 0 C) could lead to a larger TBE then after irradiation alone. When hyperthermia was given prior to irradiation, the interval between heat and irradiation proved to be very important. With large intervals (21 days or longer), TBE values were about the same as with irradiation alone. When heat was given after irradiation, irradiation-induced TBE was always reduced. (UK)

  10. H-2 restriction of the T cell response to chemically induced tumors: evidence from F1 → parent chimeras

    International Nuclear Information System (INIS)

    Lannin, D.R.; Yu, S.; McKhann, C.F.

    1982-01-01

    It has been well established that T cells that react to tumor antigen on virus-induced tumors must share H-2D or H-2K specificities with the tumor. It has been impossible to perform similar studies with chemically induced tumors because each chemically induced tumor expresses a unique tumor antigen that cannot be studied in association with other H-2 types. This study provies evidence that H-2 recognition is also necessary for recognition of chemically induced tumors. We have found that F 1 → parent chimeras preferentially recognize chemically induced tumors of parental H-2 type. C3H/HeJ and C57BL/6 mice were lethally irradiated and restored with (C3H x C57BL/6) F 1 hybrid bone marrow. The F 1 → C3H chimera but not the F 1 → C57BL/6 chimera was able to respond to a C3H fibrosarcoma in mixed lymphocyte-tumor cell culture and also to neutralize the tumor in an in vivo tumor neutralization assay. On the other hand, the F 1 → C57BL/6 chimera but not the F 1 → C3H chimera was able to kill the C57BL/6 lymphoma EL4 in an in vitro cytotoxicity assay. Both chimeras were tolerant to C3H and C57BL/6 alloantigens but could respond normally to Con A and to BALB/c spleen cells in mixed lymphocyte cultures and cytotoxicity assay

  11. Effects of high-frequency near-infrared diode laser irradiation on the proliferation and migration of mouse calvarial osteoblasts.

    Science.gov (United States)

    Kunimatsu, Ryo; Gunji, Hidemi; Tsuka, Yuji; Yoshimi, Yuki; Awada, Tetsuya; Sumi, Keisuke; Nakajima, Kengo; Kimura, Aya; Hiraki, Tomoka; Abe, Takaharu; Naoto, Hirose; Yanoshita, Makoto; Tanimoto, Kotaro

    2018-01-04

    Laser irradiation activates a range of cellular processes and can promote tissue repair. Here, we examined the effects of high-frequency near-infrared (NIR) diode laser irradiation on the proliferation and migration of mouse calvarial osteoblastic cells (MC3T3-E1). MC3T3-E1 cells were cultured and exposed to high-frequency (30 kHz) 910-nm diode laser irradiation at a dose of 0, 1.42, 2.85, 5.7, or 17.1 J/cm 2 . Cell proliferation was evaluated with BrdU and ATP concentration assays. Cell migration was analyzed by quantitative assessment of wound healing using the Incucyt ® ZOOM system. In addition, phosphorylation of mitogen-activated protein kinase (MAPK) family members including p38 mitogen-activated protein kinase (p38), stress-activated protein kinase/Jun-amino-terminal kinase (SAPK/JNK), and extracellular signal-regulated protein kinase (ERK)1/2) after laser irradiation was examined with western blotting. Compared to the control, cell proliferation was significantly increased by laser irradiation at a dose of 2.85, 5.7, or 17.1 J/cm 2 . Laser irradiation at a dose of 2.85 J/cm 2 induced MC3T3-E1 cells to migrate more rapidly than non-irradiated control cells. Irradiation with the high-frequency 910-nm diode laser at a dose of 2.85 J/cm 2 induced phosphorylation of MAPK/ERK1/2 15 and 30 min later. However, phosphorylation of p38 MAPK and SAPK/JNK was not changed by NIR diode laser irradiation at a dose of 2.85 J/cm 2 . Irradiation with a high-frequency NIR diode laser increased cell division and migration of MT3T3-E1 cells, possibly via MAPK/ERK signaling. These observations may be important for enhancing proliferation and migration of osteoblasts to improve regeneration of bone tissues.

  12. Repair capacity of mouse lung after total body irradiation alone or combined with cyclophosphamide

    International Nuclear Information System (INIS)

    Safwat, Akmal; Bentzen, Soeren M.; Nielsen, Ole S.; Mahmoud, Hossam K.; Overgaard, Jens

    1996-01-01

    Purpose. Cyclophosphamide (CTX) combined with fractionated total body irradiation (TBI) is frequently used in the conditioning of patients prior to bone marrow transplantation (BMT). This study was performed to investigate the effect of CTX on the repair capacity of lung tissue after TBI in a mouse model for BMT. Materials and methods. TBI was given as a single fraction, 3 fractions in 3 days (Fx 3) or 9 fractions in 3 days (Fx 9) either alone or 24 h after a single dose of CTX. The single fraction TBI was given at either high dose rate (HDR) of 0.71 Gy/min or low dose rate (LDR) of 0.08 Gy/min. All mice were transplanted 4-6 h after the last TBI fraction. Lung damage was assessed using ventilation rate (VR) and lethality between 28 and 180 days. The repair capacity of lung tissue was estimated using the direct analysis method with the probability of reaching the end point described by a logistic formulation of the linear quadratic model. Results. The VR data confirmed the high repair capacity of lung tissue with an α/β ratio of 4.4 Gy though with a wide 95% confidence interval (CI = 0.03-10.5). Giving CTX before fractionated TBI marked reduced the doses needed to cause response in 50% of the animals. The sparing effect of using fractionated TBI was still evident in the combined CTX-TBI schedules. The estimated α/β ratio was 1.6 Gy (CI = 0.01-4.7) which is within the range of values reported after thoracic radiation only. On the other hand, the sparing effect seen in going from single fraction HDR to LDR was completely abolished when CTX was given 24 h before TBI. The same pattern was repeated when lethality between 28-180 days was used. Yet, the use of lethality to estimate lung damage in a TBI model, markedly underestimated the repair capacity. Conclusions. These results confirm the high repair capacity of lung tissue after TBI and emphasize the value of using a specific end point in testing lung damage after TBI. It also shows that there can be a negative

  13. Effects of caffeine on protein phosphorylation and cell cycle progression in X-irradiated two-cell mouse embryos

    International Nuclear Information System (INIS)

    Jung, Th.; Streffer, C.

    1992-01-01

    To understand the mechanism of the caffeine-induced uncoupling of mitosis and the cellular reactions to DNA-damaging agents, the authors studied the effects of caffeine treatment on cell cycle progression and protein phosphorylation in two-cell mouse embryos after X-irradiation. Caffeine alone had no effect on timing of and changes in phosphorylation associated with the embryonic cell cycle. In combination with X-rays, caffeine was able to override the radiation induced G 2 block and restored normal timing of these phosphorylation changes after X-irradiation. New additional changes in protein phosphorylation appeared after the combined treatment. Isobutyl-methylxanthine (IBMX), a substance chemically related to caffeine but a more specific inhibitor of the phosphodiesterase that breaks down cyclic AMP, reduced radiation induced G 2 block from 4 to 5 h to about 1 h and restored the cell cycle associated changes in protein phosphorylation. (author)

  14. Effects of caffeine on protein phosphorylation and cell cycle progression in X-irradiated two-cell mouse embryos

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Th. (AFRC Institute of Animal Physiology and Genetics Research, Babraham (United Kingdom)); Streffer, C. (Essen Univ (Germany). Inst. fuer Medizinische Strahlenbiolgie)

    1992-08-01

    To understand the mechanism of the caffeine-induced uncoupling of mitosis and the cellular reactions to DNA-damaging agents, the authors studied the effects of caffeine treatment on cell cycle progression and protein phosphorylation in two-cell mouse embryos after X-irradiation. Caffeine alone had no effect on timing of and changes in phosphorylation associated with the embryonic cell cycle. In combination with X-rays, caffeine was able to override the radiation induced G[sub 2] block and restored normal timing of these phosphorylation changes after X-irradiation. New additional changes in protein phosphorylation appeared after the combined treatment. Isobutyl-methylxanthine (IBMX), a substance chemically related to caffeine but a more specific inhibitor of the phosphodiesterase that breaks down cyclic AMP, reduced radiation induced G[sub 2] block from 4 to 5 h to about 1 h and restored the cell cycle associated changes in protein phosphorylation. (author).

  15. G/sub 2/ arrest in mouse zygotes after X-irradiation: reversion by caffeine and influence of chromosome abnormalities

    Energy Technology Data Exchange (ETDEWEB)

    Grinfeld, S.; Jacquet, P.

    1988-08-01

    The effect of caffeine was studied on mouse zygotes blocked in the G/sub 2/ phase of the first cell cycle after X-irradiation. Caffeine (2 mM) effectively reversed the G/sub 2/ arrest when zygotes were incubated in its presence at the time when first mitosis normally takes place. This effect of caffeine was inhibited by cycloheximide (5 ..mu..g ml/sup -1/). In embryos escaping the G/sub 2/ arrest the frequencies of chromosome aberrations varied as a function of the time of irradiation, showing a clear relationship with the varying rates of lethality occurring from the morula stage. Blocked zygotes suffered major chromosome damage: however, this did not appear to be the only cause of the G/sub 2/ arrest. Triploid zygotes were preferentially blocked, suggesting that nuclei contain the target for this X-ray effect.

  16. Acute response of mouse kidney clonogens to fractionated irradiation in situ and then assayed in primary culture

    International Nuclear Information System (INIS)

    Yeemin Jen; Hendry, J.H.

    1991-01-01

    The radiosensitivity of mouse kidney cells after in situ single-dose, 2, 8, and 16 fraction X-irradiations was measured in primary culture using a clonogenic assay. The assay was made 12 h after single doses or 12 h after the last dose of the multifraction regimens. When analysed using the linear-quadratic model, as predicted the individual α components for all the different fractionation schedules were not significantly different, and the changes in the β values were consistent with those expected on the basis of the reciprocal fraction numbers. When all four data sets were integrated to derive a common α/β ratio, the result was 4.4±1.3 (1SE) Gy, or 2.8±0.9 Gy (a better fit) if the single-dose data set was excluded. These values fall into the range reported for kidney using assays of tissue function at long times after irradiation. (author)

  17. Migration inhibition of immune mouse spleen cells by serum from x-irradiated tumor-bearing mice

    International Nuclear Information System (INIS)

    Moroson, H.

    1978-01-01

    Tumor-specific antigens of the chemically induced MC 429 mouse fibrosarcoma were detected in a 3 M KCl extract of tumor by the inhibition of migration of specifically immune spleen cells. Using this assay with serum from tumor-bearing mice no tumor antigen was detected in serum of mice bearing small tumors, unless the tumor was exposed to local x irradiation (3000 R) 1 day prior to collection of serum. It was concluded that local x irradiation of tumor caused increased concentration of tumor antigen in the serum. When the tumor was allowed to grow extremely large, with necrosis, then host serum did cause migration inhibition of both nonimmune and immune spleen cells. This migration-inhibition effect was not associated with tumor antigen, but with a nonspecific serum factor

  18. Effects of fast neutron irradiation on the development of the mouse brain

    International Nuclear Information System (INIS)

    Deguchi, Hisao

    1977-01-01

    Mice on the 4th to 11th day of pregnancy were irradiated with 14.1 MeV fast neutron at a dose of 100 rad and their fetuses were examined macroscopically and histologically on the 9th to the 19th day of gestation. Sixty-one cases out of 73 malformed fetuses (20.3%) were arbitrarily chosen and examined. Two cases of exencephaly were observed by irradiation on the 7th day of pregnancy, 2 cases of microcephaly by irradiation on the 9th day, 2 cases of hydrocephaly by irradiation on the 6th day and 3 cases of hydrocephaly by irradiation on the 11th day. Three cases of tumor were observed by irradiation on the 7th day of pregnancy and one case of tumor by irradiation on the 10th day. One case each of abnormal folding of the pallium was detected by irradiation on the 7th day and 10th day of pregnancy. After irradiation, penetration of blood vessels into the developing brain resembles to that of the control group. In some cases, invasion of fibroblast-like cells was observed. In cases with tumor formation, the tumors consisted of homogeneous ventricular cells without any sign of malignancy. Three to four days after irradiation on the 10th or 11th day of pregnancy, rosette formation was observed in the pallium which later disappeared. It appears that slight damages of brain tissue could be repaired without resulting in any external morphological abnormalities. (auth.)

  19. Transition pattern and mechanism of B-lymphocyte precursors in regenerated mouse bone marrow after subtotal body irradiation.

    Directory of Open Access Journals (Sweden)

    Deping Han

    Full Text Available Little is known about the effects of ionizing radiation on the transition and the related signal transduction of progenitor B cells in the bone marrow. Thus, using an NIH Swiss mouse model, we explored the impact of ionizing radiation on the early stage of B-cell development via an examination of the transition of CLP to pro-B to pre-B cells within bone marrow as a function of radiation doses and times. Our results showed that while the total number of bone marrow lymphoid cells at different stages were greatly reduced by subtotal body irradiation (sub-TBI, the surviving cells continued to transition from common lymphoid progenitors to pro-B and then to pre-B in a reproducible temporal pattern. The rearrangement of the immunoglobulin heavy chain increased significantly 1-2 weeks after irradiation, but no change occurred after 3-4 weeks. The rearrangement of the immunoglobulin light chain decreased significantly 1-2 weeks after sub-TBI but increased dramatically after 3-4 weeks. In addition, several key transcription factors and signaling pathways were involved in B-precursor transitions after sub-TBI. The data indicate that week 2 after irradiation is a critical time for the transition from pro-B cells to pre-B cells, reflecting that the functional processes for different B-cell stages are well preserved even after high-dose irradiation.

  20. Embryonic death, dwarfism and fetal malformations after irradiation of embryos at the zygote stage. Studies on two mouse strains

    International Nuclear Information System (INIS)

    Jacquet, P.; Saint-Georges, L. de; Baugnet-Mahieu, L.; Vankerkom, J.

    1995-01-01

    Female mice of the BALB/c and CF1 strains were mated and irradiated with various doses of X-rays 7 h after presumed fertilization. 18 days later, females were killed and their uteri examined for prenatal mortality at the different stages of development. Living fetuses were weighed and examined for the presence of external malformations. A number of them were also examined for skeletal anomalies. Radiation induced mainly a dose-dependent increase of the preimplantation loss in the BALB/c strain and of the early postimplantation loss in the CF1 strain. Embryos of the BALB/c strain were refractory to the induction of teratogenic effects after such preimplantation irradiation. In CF1 mice, the frequency of malformed fetuses increased regularly after irradiation, the difference with controls being significant for the doses of 10, 50 and 100 cGy. Dwarfism occurrence also appeared to be increased by irradiation in this strain, although the importance of this effect varied depending on the criterion chosen for the assessment of dwarfs. With the definition proposed in the present paper, the increase in the frequency of dwarfs paralleled that of malformed fetuses, being significant after doses of 50 and 100 cGy. Irradiation did not increase the frequency of skeletal anomalies. A careful examination of the various data obtained to date led us to conclude that radiation may possibly be teratogenic in several mouse strains, when administered as early as during the one-cell stage and, to a lesser extent, during the following preimplantation stages. However, early prenatal mortality will remain by far the greatest risk associated with an exposure to radiation during this period. Moreover, the relativity of the risk of abnormality due to such irradiation should be considered in the context of the high prevalence of developmental defects spontaneously occurring during human pregnancy

  1. Molecular Understanding of Growth Inhibitory Effect from Irradiated to Bystander Tumor Cells in Mouse Fibrosarcoma Tumor Model

    Science.gov (United States)

    Desai, Sejal; Srambikkal, Nishad; Yadav, Hansa D.; Shetake, Neena; Balla, Murali M. S.; Kumar, Amit; Ray, Pritha; Ghosh, Anu

    2016-01-01

    Even though bystander effects pertaining to radiation risk assessment has been extensively studied, the molecular players of radiation induced bystander effect (RIBE) in the context of cancer radiotherapy are poorly known. In this regard, the present study is aimed to investigate the effect of irradiated tumor cells on the bystander counterparts in mouse fibrosarcoma (WEHI 164 cells) tumor model. Mice co-implanted with WEHI 164 cells γ-irradiated with a lethal dose of 15 Gy and unirradiated (bystander) WEHI 164 cells showed inhibited tumor growth, which was measured in terms of tumor volume and Luc+WEHI 164 cells based bioluminescence in vivo imaging. Histopathological analysis and other assays revealed decreased mitotic index, increased apoptosis and senescence in these tumor tissues. In addition, poor angiogenesis was observed in these tumor tissues, which was further confirmed by fluorescence imaging of tumor vascularisation and CD31 expression by immuno-histochemistry. Interestingly, the growth inhibitory bystander effect was exerted more prominently by soluble factors obtained from the irradiated tumor cells than the cellular fraction. Cytokine profiling of the supernatants obtained from the irradiated tumor cells showed increased levels of VEGF, Rantes, PDGF, GMCSF and IL-2 and decreased levels of IL-6 and SCF. Comparative proteomic analysis of the supernatants from the irradiated tumor cells showed differential expression of total 24 protein spots (21 up- and 3 down-regulated) when compared with the supernatant from the unirradiated control cells. The proteins which showed substantially higher level in the supernatant from the irradiated cells included diphosphate kinase B, heat shock cognate, annexin A1, angiopoietin-2, actin (cytoplasmic 1/2) and stress induced phosphoprotein 1. However, the levels of proteins like annexin A2, protein S100 A4 and cofilin was found to be lower in this supernatant. In conclusion, our results provided deeper insight about

  2. Embryonic death, dwarfism and fetal malformations after irradiation of embryos at the zygote stage. Studies on two mouse strains

    Energy Technology Data Exchange (ETDEWEB)

    Jacquet, P.; Saint-Georges, L. de; Baugnet-Mahieu, L. [Laboratory of Radiobiology, Department of Radioprotection, CEN/SCK, Mol (Belgium); Vankerkom, J. [Division of Environmental Research, VITO, Mol (Belgium)

    1995-11-01

    Female mice of the BALB/c and CF1 strains were mated and irradiated with various doses of X-rays 7 h after presumed fertilization. 18 days later, females were killed and their uteri examined for prenatal mortality at the different stages of development. Living fetuses were weighed and examined for the presence of external malformations. A number of them were also examined for skeletal anomalies. Radiation induced mainly a dose-dependent increase of the preimplantation loss in the BALB/c strain and of the early postimplantation loss in the CF1 strain. Embryos of the BALB/c strain were refractory to the induction of teratogenic effects after such preimplantation irradiation. In CF1 mice, the frequency of malformed fetuses increased regularly after irradiation, the difference with controls being significant for the doses of 10, 50 and 100 cGy. Dwarfism occurrence also appeared to be increased by irradiation in this strain, although the importance of this effect varied depending on the criterion chosen for the assessment of dwarfs. With the definition proposed in the present paper, the increase in the frequency of dwarfs paralleled that of malformed fetuses, being significant after doses of 50 and 100 cGy. Irradiation did not increase the frequency of skeletal anomalies. A careful examination of the various data obtained to date led us to conclude that radiation may possibly be teratogenic in several mouse strains, when administered as early as during the one-cell stage and, to a lesser extent, during the following preimplantation stages. However, early prenatal mortality will remain by far the greatest risk associated with an exposure to radiation during this period. Moreover, the relativity of the risk of abnormality due to such irradiation should be considered in the context of the high prevalence of developmental defects spontaneously occurring during human pregnancy.

  3. Molecular Understanding of Growth Inhibitory Effect from Irradiated to Bystander Tumor Cells in Mouse Fibrosarcoma Tumor Model.

    Directory of Open Access Journals (Sweden)

    Sejal Desai

    Full Text Available Even though bystander effects pertaining to radiation risk assessment has been extensively studied, the molecular players of radiation induced bystander effect (RIBE in the context of cancer radiotherapy are poorly known. In this regard, the present study is aimed to investigate the effect of irradiated tumor cells on the bystander counterparts in mouse fibrosarcoma (WEHI 164 cells tumor model. Mice co-implanted with WEHI 164 cells γ-irradiated with a lethal dose of 15 Gy and unirradiated (bystander WEHI 164 cells showed inhibited tumor growth, which was measured in terms of tumor volume and Luc+WEHI 164 cells based bioluminescence in vivo imaging. Histopathological analysis and other assays revealed decreased mitotic index, increased apoptosis and senescence in these tumor tissues. In addition, poor angiogenesis was observed in these tumor tissues, which was further confirmed by fluorescence imaging of tumor vascularisation and CD31 expression by immuno-histochemistry. Interestingly, the growth inhibitory bystander effect was exerted more prominently by soluble factors obtained from the irradiated tumor cells than the cellular fraction. Cytokine profiling of the supernatants obtained from the irradiated tumor cells showed increased levels of VEGF, Rantes, PDGF, GMCSF and IL-2 and decreased levels of IL-6 and SCF. Comparative proteomic analysis of the supernatants from the irradiated tumor cells showed differential expression of total 24 protein spots (21 up- and 3 down-regulated when compared with the supernatant from the unirradiated control cells. The proteins which showed substantially higher level in the supernatant from the irradiated cells included diphosphate kinase B, heat shock cognate, annexin A1, angiopoietin-2, actin (cytoplasmic 1/2 and stress induced phosphoprotein 1. However, the levels of proteins like annexin A2, protein S100 A4 and cofilin was found to be lower in this supernatant. In conclusion, our results provided deeper

  4. Evaluation of cell regeneration of bone marrow after fractionated irradiation of mouse in toto

    International Nuclear Information System (INIS)

    Maisin, H.; Evercoren, A. van; Anckaert, M.A.; Coster, B.M. de

    1979-01-01

    We have studied the recovery for mice bone marrow cells after fractionated irradiation of the whole body. The additional dose (Dr) to obtain a given biological effect if the irradiation is split in two equal subfractions (2 Di) separated by a short interval of time (i) is 40 rad per day when the interval of time between the two irradiations is lenghtened of one day [fr

  5. Surface damage in the small intestine of the mouse after X - or neutron irradiation

    International Nuclear Information System (INIS)

    Hamlet, R.; Carr, K.E.; Nias, A.H.; Watt, C.

    1981-01-01

    Damage after X-irradiation includes lateral villous collapse, progressing after 3 - 5 days to villi which sometimes show signs of vertical collapse. After neutron irradiation vertical villous collapse is established earlier, with less swelling of villous tips. It seems, therefore, that at radiobiologically equivalent doses, neutron and X-irradiation produce different levels of surface damage, with neutron irradiation being the more destructive. Early villous tip damage may perhaps be due to disruption of susceptible cells already at the extrusion zone, or to stromal damage

  6. Growth control of genetically modified cells using an antibody/c-Kit chimera.

    Science.gov (United States)

    Kaneko, Etsuji; Kawahara, Masahiro; Ueda, Hiroshi; Nagamune, Teruyuki

    2012-05-01

    Gene therapy has been regarded as an innovative potential treatment against serious congenital diseases. However, applications of gene therapy remain limited, partly because its clinical success depends on therapeutic gene-transduced cells acquiring a proliferative advantage. To address this problem, we have developed the antigen-mediated genetically modified cell amplification (AMEGA) system, which uses chimeric receptors to enable the selective proliferation of gene-transduced cells. In this report, we describe mimicry of c-Kit signaling and its application to the AMEGA system. We created an antibody/c-Kit chimera in which the extracellular domain of c-Kit is replaced with an anti-fluorescein single-chain Fv antibody fragment and the extracellular D2 domain of the erythropoietin receptor. A genetically modified mouse pro-B cell line carrying this chimera showed selective expansion in the presence of fluorescein-conjugated BSA (BSA-FL) as a growth inducer. By further engineering the transmembrane domain of the chimera to reduce interchain interaction we attained stricter ligand-dependency. Since c-Kit is an important molecule in the expansion of hematopoietic stem cells (HSCs), this antibody/c-Kit chimera could be a promising tool for gene therapy targeting HSCs. Copyright © 2011 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  7. EPR detection of free radicals in UV-irradiated skin: mouse versus human

    International Nuclear Information System (INIS)

    Jurkiewicz, B.A.; Buettner, G.R.

    1996-01-01

    Ultraviolet radiation produces free radicals in Skh-1 mouse skin, contributing to photoaging and carcinogenesis. If a mouse model is a general indicator of free radical processes in human skin photobiology, then radical production observed in mouse and human skin should be directly comparative. In this work we show that UV radiation (λ > 300 nm, 14 μW/cm 2 UVB; 3.5 mW/cm 2 UVA) increases the ascorbate free radical (Asc) electron paramagnetic resonance (EPR) signal in both Skh-1 mouse skin (45%) and human facial skin biopsies (340%). Visible light (λ > 400 nm; 0.23 mW/cm 2 UVA) also increased the Ascsignal in human skin samples (45%) but did not increase baseline mouse Asc, indicating that human skin is more susceptible to free radical formation and that a chromophore for visible light may be present. Using EPR spin-trapping techniques, UV radiation produced spin adducts consistent with trapping lipid alkyl radicals in mouse skin (α-[4-pyridyl 1-oxide]-N-tert-butyl nitrone/alkyl radical adduct; a N = 15.56 G and a H 2.70 G) and lipid alkoxyl radicals in human skin (5,5-dimethylpyrroline -1-oxide/alkoxyl radical adduct; a N = 14.54 G and a H = 16.0 G). Topical application of the iron chelator Desferal to human skin significantly decreases these radicals (∼50%), indicating a role for iron in lipid peroxidation. (Author)

  8. Antibody responses in allogeneic radiation chimeras

    International Nuclear Information System (INIS)

    Coico, R.F.

    1982-01-01

    The construction of long-lived allogeneic radiation chimeras, free of graft-versus-host disease, has been achieved using serologic elimination of Thy 1 + cells from donor bone marrow. Humoral immune function was not restored in these animals as evidenced by lack of primary antibody responses to a T cell-dependent antigen, namely, sheep erythrocytes (SRBC) both in vivo and in vitro. No evidence for a suppressor cell-mediated mechanism was found. Using separated chimera spleen cell populations and specific helper cell soluble mediators, the functional capabilities of chimera B cells, T cells, and macrophages were assessed. These findings suggested that the failure of chimeras to produce antibody is not the result of impaired B cell, T cell, or macrophage function, but rather, that it is due to ineffective cellular interactions. Physiologic cellular interactions depend upon the sharing of major histocompatibility complex (MHC) determinants between interacting cells. However, the self-recognition repertoire of developing T cells may be influenced by the environment which these cells differentiate such that they learn to recognize host MHC determinants as self. These findings support the interpretation that the immunologic hyporeactivity of allogeneic bone marrow chimeras reflects the role of the host environment in restricting the interactive capabilities of donor-derived cells

  9. Chimera states in mechanical oscillator networks.

    Science.gov (United States)

    Martens, Erik Andreas; Thutupalli, Shashi; Fourrière, Antoine; Hallatschek, Oskar

    2013-06-25

    The synchronization of coupled oscillators is a fascinating manifestation of self-organization that nature uses to orchestrate essential processes of life, such as the beating of the heart. Although it was long thought that synchrony and disorder were mutually exclusive steady states for a network of identical oscillators, numerous theoretical studies in recent years have revealed the intriguing possibility of "chimera states," in which the symmetry of the oscillator population is broken into a synchronous part and an asynchronous part. However, a striking lack of empirical evidence raises the question of whether chimeras are indeed characteristic of natural systems. This calls for a palpable realization of chimera states without any fine-tuning, from which physical mechanisms underlying their emergence can be uncovered. Here, we devise a simple experiment with mechanical oscillators coupled in a hierarchical network to show that chimeras emerge naturally from a competition between two antagonistic synchronization patterns. We identify a wide spectrum of complex states, encompassing and extending the set of previously described chimeras. Our mathematical model shows that the self-organization observed in our experiments is controlled by elementary dynamical equations from mechanics that are ubiquitous in many natural and technological systems. The symmetry-breaking mechanism revealed by our experiments may thus be prevalent in systems exhibiting collective behavior, such as power grids, optomechanical crystals, or cells communicating via quorum sensing in microbial populations.

  10. Detection of irradiation-induced, membrane heat shock protein 70 (Hsp70) in mouse tumors using Hsp70 Fab fragment

    International Nuclear Information System (INIS)

    Stangl, Stefan; Themelis, George; Friedrich, Lars; Ntziachristos, Vasilis; Sarantopoulos, Athanasios; Molls, Michael; Skerra, Arne; Multhoff, Gabriele

    2011-01-01

    Background and purpose: The major stress-inducible heat shock protein 70 (Hsp70) is frequently overexpressed in highly aggressive tumors, and elevated intracellular Hsp70 levels mediate protection against apoptosis. Following therapeutic intervention, such as ionizing irradiation, translocation of cytosolic Hsp70 to the plasma membrane is selectively increased in tumor cells and therefore, membrane Hsp70 might serve as a therapy-inducible, tumor-specific target structure. Materials and methods: Based on the IgG1 mouse monoclonal antibody (mAb) cmHsp70.1, we produced the Hsp70-specific recombinant Fab fragment (Hsp70 Fab), as an imaging tool for the detection of membrane Hsp70 positive tumor cells in vitro and in vivo. Results: The binding characteristics of Hsp70 Fab towards mouse colon (CT26) and pancreatic (1048) carcinoma cells at 4 deg. C were comparable to that of cmHsp70.1 mAb, as determined by flow cytometry. Following a temperature shift to 37 deg. C, Hsp70 Fab rapidly translocates into subcellular vesicles of mouse tumor cells. Furthermore, in tumor-bearing mice Cy5.5-conjugated Hsp70 Fab, but not unrelated IN-1 control Fab fragment (IN-1 ctrl Fab), gradually accumulates in CT26 tumors between 12 and 55 h after i.v. injection. Conclusions: In summary, the Hsp70 Fab provides an innovative, low immunogenic tool for imaging of membrane Hsp70 positive tumors, in vivo.

  11. The proliferative response of mouse intestinal crypts during fractionated irradiation of carbon beams

    International Nuclear Information System (INIS)

    Abo, M.; Abe, Y.; Mariya, Y.; Ando, K.

    2000-01-01

    Clonogenic assay of jejunal crypt during carbon beam and X-ray irradiations was performed. Fractionation with top-up dose assay revealed carbon beam irradiations caused more damage than X-ray did. To clarify this problem is urgent. (author)

  12. Differential proteiomic analysis of mouse intestinal epithelium irradiated by γ-ray

    International Nuclear Information System (INIS)

    Zhang Bo; Su Yongping; Liu Xiaohong; Ai Guoping; Ran Xinze; Wei Yongjiang; Wang Junping; Cheng Tianmin

    2003-01-01

    Objective: For elucidating the molecular mechanism of reconstruction of intestinal epithelium damaged by ionizing radiation, the proteomes of murine intestinal epithelium from normal and irradiated mice were compared by 2-D electrophoresis. Methods: Histopathologic sections of whole small intestine made from BALB/c mice 3 h and 72 h after total-body irradiation were stained with hematoxylin-eosin. Intestinal epithelial cells were isolated from normal and irradiated mice. The total protein samples prepared by one-step method were used in 2-D electrophoresis, the protein maps were compared and the differential spots were detected with PDQuest analysis software. Twenty-eight different spots were cut off from the gels, digested in gel with trypsin, measured with MALDI-TOF-MS and searched in database. Results: Small intestinal epithelium was damaged as early as 3 h after irradiation, and reconstructed 72 h later. After Coomassie-staining, the 2-DE image analysis by PDQuest software detected 638 ± 39 protein spots in normal mice group, 566 ± 32 spots in 3 hours post irradiation group, and 591 ± 29 spots in 3 days post irradiation group. The 2-DE images showed that proteomes of intestinal epithelium were altered with γ-irradiation. The proteins identified by peptide mass fingerprinting involved in cellular events, including signal transduction, metabolism and oxidative stress responses. Conclusions: Gamma-irradiation can induce the protein expression of intestinal epithelium. The technique of 2-D electrophoresis is a useful tool in the study of molecular mechanism of radiation damage

  13. Influence of a sublethal irradiation on the immune response of the mouse against sheep erythrocytes

    International Nuclear Information System (INIS)

    Beaumariage, M.L.; Hiesche, K.; Moeller, E.; Revesz, L.; Haot, J.

    1975-01-01

    In the CBA mice, the immunological response of the spleen cells (RFC and PFC direct and indirect) against the sheep erythrocytes is highly depressed by a 400R dose of X rays. The recovery is not complete at the 30th day after irradiation. The response of the bone marrow cells either irradiated or unirradiated to the antigenic stimulation is very low [fr

  14. Chimera states: Effects of different coupling topologies

    Science.gov (United States)

    Bera, Bidesh K.; Majhi, Soumen; Ghosh, Dibakar; Perc, Matjaž

    2017-04-01

    Collective behavior among coupled dynamical units can emerge in various forms as a result of different coupling topologies as well as different types of coupling functions. Chimera states have recently received ample attention as a fascinating manifestation of collective behavior, in particular describing a symmetry breaking spatiotemporal pattern where synchronized and desynchronized states coexist in a network of coupled oscillators. In this perspective, we review the emergence of different chimera states, focusing on the effects of different coupling topologies that describe the interaction network connecting the oscillators. We cover chimera states that emerge in local, nonlocal and global coupling topologies, as well as in modular, temporal and multilayer networks. We also provide an outline of challenges and directions for future research.

  15. Effects of irradiation on the biology of the infective larvae of Toxocara canis in the mouse

    Energy Technology Data Exchange (ETDEWEB)

    Barriga, O.O.; Myser, W.C.

    1987-02-01

    Mice were infected with either 2000 normal or irradiated embryonated eggs of Toxocara canis and the number of larvae in their livers, lungs, brains, and carcasses investigated at 5, 20, and 33 days of infection. Mortality of mice infected with normal eggs was 33% between day 4 and 8 postinfection but there was no mortality among mice infected with irradiated eggs. Irradiation with 60, 90, or 150 kr of X-rays inhibited the migration of larvae from the livers and lungs and their accumulation in brain and carcass in proportion to the irradiation dose. By day 33 of infection, the ratio of larvae in liver and lungs to larvae in brain and carcass was 0.16 in normal mice, 0.42 in 60-kr mice, 0.98 in 90-kr mice, and 23.3 in 150-kr mice. Irradiated larvae, particularly those migrating through the peritoneal cavity, died faster than normal larvae until day 20. Irradiation favored survival after day 20. By days 20 and 33 postinfection the total parasite load was 29% and 8%, respectively, of the administered dose in control mice, 18% and 12% in 60-kr mice, 8% and 4% in 90-kr mice, and 0.9% and 0.3% in 150-kr mice. Irradiation of infective T. canis larvae, then, reduces their pathogenicity, inhibits their migration from liver and lungs, kills some of the parasites during the first 3 weeks of infection, but favors their late survival in the host.

  16. The electrocorticograms of the aged mouse x-irradiated at juvenile or young adult

    International Nuclear Information System (INIS)

    Minamisawa, Takeru; Sasaki, Shunsaku.

    1984-01-01

    The electrocorticograms (ECoGs) of the (C57BL/6 x C3H)F 1 mice irradiated at juvenile or young adult were studied when they attained the age of 24-26 months. One group of mice was irradiated 35 days post partum (35-DPP) and another 105 days (105-DPP). All the animals were irradiated with 300 R of X-rays to whole body. The ECoGs were recorded from the freely moving animals with the permanently implanted electrodes fixed over the visual cortical surface. The resulted ECoGs were divided into 3 patterns: wakefulness (W), slow wave sleep (SWS), and paradoxical sleep (PS). Six parameters of the 3 patterns were compared among the 2 irradiated groups and the non-irradiated control group. The mean SWS- and PS-cycle times, and mean SWS length were significantly longer in the 35-DPP group than in the control group. Changes in the ECoGs were less profound in the 105-DPP group than those in the 35-DPP group: only a significant change due to irradiation at 105-DPP was a decrease in the ratio of the total PS time to the total sleep time (TST = total SWS time + total PS time). There was no difference in the body weight and brain weight among the 2 irradiated groups and the control group. (author)

  17. Low-dose carbon ion irradiation effects on DNA damage and oxidative stress in the mouse testis

    Science.gov (United States)

    Liu, Yang; Long, Jing; Zhang, Luwei; Zhang, Hong; Liu, Bin; Zhao, Weiping; Wu, Zhehua

    2011-01-01

    To investigate the effects of low-dose carbon ion irradiation on reproductive system of mice, the testes of outbred Kunming strain mice were whole-body irradiated with 0, 0.05, 0.1, 0.5 and 1 Gy, respectively. We measured DNA double-strand breaks (DNA DSBs) and oxidative stress parameters including malondialdehyde (MDA) content, superoxide dismutase (SOD) activity, and testis weight and sperm count at 12 h, 21 d and 35 d after irradiation in mouse testis. At 12 h postirradiation, a significant increase in DNA DSB level but no pronounced alterations in MDA content or SOD activity were observed in 0.5 and 1 Gy groups compared with the control group. At 21 d postirradiation, there was a significant reduction in sperm count and distinct enhancements of DSB level and MDA content in 0.5 and 1 Gy groups in comparison with control. At 35 d postirradiation, the levels of DNA DSBs and MDA, and SOD activity returned to the baseline except for the MDA content in 1 Gy (P sperm count were still observed in 0.5 (P sperm count. Furthermore, these data suggest that the deleterious effects may be chronic or delayed in reproductive system after whole-body exposure to acute high-dose carbon ions.

  18. Development of a new mouse palate organ culture system and effect of X-irradiation on palatogenesis

    International Nuclear Information System (INIS)

    Hiranuma, Hiroko; Jikko, Akitoshi; Maeda, Takashi; Furukawa, Souhei

    1999-01-01

    On the basis of an already established suspension system of organ culture for mouse palate explants, we developed a new culture system, which has several advantages over the previous methods. We used a 48-well culture plate in which the explants can be cultured individually, and only 300 μl of medium is needed for each well. In order to optimize the culture results, we systematically studied the influence of main ''culture conditions'' such as tilt degree of the culturing palate, rotation speed, and addition of ascorbic acid to the medium. This system allows culturing of palates from day 13.5 of gestation to day 16.5 under serum-free conditions using a chemically defined medium, which resulted in 78% of the palates growing fused. Utilizing this culture system, the direct effect of X-irradiation on palataogesis was analyzed. A 4 Gy dose of X-irradiation was administrated at the beginning of culture period. The incidence of palatal fusion was not significantly different from that of the non-irradiated group. (author)

  19. Effect of Thai banana (Musa AA group) in reducing accumulation of oxidation end products in UVB-irradiated mouse skin.

    Science.gov (United States)

    Leerach, Nontaphat; Yakaew, Swanya; Phimnuan, Preeyawass; Soimee, Wichuda; Nakyai, Wongnapa; Luangbudnark, Witoo; Viyoch, Jarupa

    2017-03-01

    Chronic UVB exposure causes skin disorders and cancer through DNA strand breaks and oxidation of numerous functional groups of proteins and lipids in the skin. In this study, we investigated the effects of Thai banana (Musa AA group, "Khai," and Musa ABB group, "Namwa") on the prevention of UVB-induced skin damage when fed to male ICR mice. Mice were orally fed banana (Khai or Namwa) fruit pulps at dose of 1mg/g body weight/day for 12weeks. The shaved backs of the mice were irradiated with UVB for 12weeks. The intensity dose of UVB-exposure was increased from 54mJ/cm 2 /exposure at week 1 to 126mJ/cm 2 /exposure at week 12. A significant increase in skin thickness, lipid peroxidation, protein oxidation end products, and expression of MMP-1 was observed in UVB-irradiated mouse skin. A reduction in the accumulation of oxidation end products was found in the skin of UVB-irradiated mice receiving Khai. This occurred in conjunction with a reduction in MMP-1 expression, inhibition of epidermal thickening, and induction of γ-GCS expression. The dietary intake of Khai prevented skin damage from chronic UVB exposure by increased γ-GCS expression and reduced oxidation end products included carbonyls, malondialdehyde and 4-hydroxynonenal. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Nicotinamide adenosine dinucleotide level in dimethylsulfate-treated or UV-irradiated mouse epidermis

    International Nuclear Information System (INIS)

    Balard, B.; Giacomoni, P.U.

    1989-01-01

    The level of nicotinamide (NAD) has been determined in the epidermis of 30 mice. Its value is 0.63+-0.15 μg/mg protein. Upon treatment with dimethylsulfate (DMS), the level of NAD drops in a dosedependent fashion. This diminution is reversible when low doses of DMS are used. Upon irradiation with ultraviolet light, the level of NAD drops in the irradiated epidermis, the treshold of saturation being below 1200 J/m 2 . There is also a drop in the level of NAD in the epidermis protected against irradiation with a black rubber sheet. (author). 17 refs.; 6 figs.; 1 tab

  1. α-Peptide/ß-Peptoid Chimeras

    DEFF Research Database (Denmark)

    Olsen, Christian Adam; Bonke, Gitte; Vedel, Line

    2007-01-01

    We describe the synthesis and characterization of the first generation of oligomers consisting of alternating repeats of a-amino acids and chiral N-alkyl-ß-alanine (ß-peptoid) residues. These chimeras are stable toward proteolysis, non-hemolytic, and possess antibacterial activity comparable...... to well-known antimicrobial agents. Moreover, the chimeras exhibit length-dependent, concentration-dependent, solvent-dependent, and ion-strength-dependent ellipticity, indicating the presence of a secondary structure in solution. Thus, a-peptide/ß-peptoid oligomers represent a promising novel...

  2. PSK, a biological response modifier, modifies p53 expression, mitosis and apoptosis in X-ray irradiated mouse embryos. Possible cellular mechanism of the anti-teratogenic effect

    International Nuclear Information System (INIS)

    Kagohashi, Yukiko; Naora, Hiroyuki; Otani, Hiroki

    2002-01-01

    We previously showed that PSK, a biological response modifier, suppressed X-ray irradiation induced ocular anomalies in mouse embryos. In the present study, in mouse embryos irradiated at E7.5, PSK, when administered immediately after irradiation, suppressed mitosis and increased apoptosis as compared with embryos not treated with PSK at 12 hrs after irradiation. In the irradiated embryos, p53, which is normally expressed at a high level in early embryos, increased at 6 hrs and decreased at 12 hrs after irradiation. In the irradiated and PSK-treated embryos, the p53 level did not change at 6 hrs, increased at 12 hrs and decreased at 24 hrs after irradiation. This timing of PSK-induced delayed increase of p53 coincided with that of the PSK-induced decrease in mitosis and increase in apoptosis. These results suggested that PSK modified the p53 level and affected cell proliferation and apoptosis, which might contribute to the suppression of teratogenesis. (author)

  3. Preconditioning With Low-Level Laser Irradiation Enhances the Therapeutic Potential of Human Adipose-derived Stem Cells in a Mouse Model of Photoaged Skin.

    Science.gov (United States)

    Liao, Xuan; Li, Sheng-Hong; Xie, Guang-Hui; Xie, Shan; Xiao, Li-Ling; Song, Jian-Xing; Liu, Hong-Wei

    2018-02-19

    This study was conducted to explore the therapeutic potential of human adipose-derived stem cells (ADSCs) irradiated with a low-level laser (LLL). Cultured ADSCs were treated with 650-nm GaAlAs laser irradiation at 2, 4 and 8 J cm -2 . Cell proliferation was quantified by MTT assays, cytokine secretion was determined by enzyme-linked immunosorbent assays, and adipogenic differentiation was examined by oil red O staining. Additionally, the expression profiles of putative ADSC surface markers were analyzed by quantitative real-time PCR. In addition, a mouse photoaged skin model was established by UVB irradiation. Effects of GaAlAs laser-treated ADSCs on the thicknesses of the epidermis and dermis were analyzed by hematoxylin and eosin staining. The results showed that GaAlAs laser treatment of cells at a radiant exposure of 4 J cm -2 enhanced ADSC proliferation and adipogenic differentiation and increased secretion of growth factors. Furthermore, GaAlAs laser irradiation upregulated the expression of putative ADSC surface markers. In the mouse model of photoaged skin, ADSCs treated with GaAlAs laser irradiation had markedly decreased the epidermal thickness and increased the dermal thickness of photoaged mouse skin. Our data indicate that LLL irradiation is an effective biostimulator of ADSCs and might enhance the therapeutic potential of ADSCs for clinical use. © 2018 The American Society of Photobiology.

  4. Gene expression profiles of irradiated lung tissue in three mouse strains

    Data.gov (United States)

    National Aeronautics and Space Administration — The aim of our research is to clarify the mechanisms generating heterogeneity in response to C-ion irradiation that arise from individual genetic variations in...

  5. Effect of whole-body irradiation by fast neutrons on mouse tissues. Pt. 1

    International Nuclear Information System (INIS)

    Kotb, M.A.; Abdel-Mawla, A.; El-Khatib, A.; Ramadan, M.I.A.; El-Bassiouni, E.A.

    1991-01-01

    Groups of male Swiss albino mice were irradiated by single doses of either 7 rem or 14 rem of fast neutrons with 14 MeV average energy, corresponding to fluences of 1.27x10 8 n/cm 2 and 2.54x10 8 n/cm 2 , respectively. The activities of acid phosphatase (ACP) and succinic dehydrogenase (SDH) in kidney, lung and liver were determined at different time point up to seven days after irradiation. Lysosomal affection was represented by statistically significant increase of ACP activity in all cell types of the three tested organs immediately after irradiation with either of the doses used. The effect of SDH was represented by reduction in activity in all three organs. The activities of both enzymes showed tendencies to return to pre-irradiation levels with time in most cell types especially after the 7 rem dose. (orig.) [de

  6. Hepatic catalase activity after whole-body irradiation of the mouse

    International Nuclear Information System (INIS)

    Neveux, Y.; Drouet, J.; Guillouzo, A.; Rault, H.; Picard, G.

    Using biochemical techniques, the effect of irradiation on catalase rate of different tissues is studied. With cytochemistry, the decrease of catalase activity is studied in situ, after exposure to great ionizing radiation doses [fr

  7. Bistable Chimera Attractors on a Triangular Network of Oscillator Populations

    DEFF Research Database (Denmark)

    Martens, Erik Andreas

    2010-01-01

    . This triangular network is the simplest discretization of a continuous ring of oscillators. Yet it displays an unexpectedly different behavior: in contrast to the lone stable chimera observed in continuous rings of oscillators, we find that this system exhibits two coexisting stable chimeras. Both chimeras are......, as usual, born through a saddle-node bifurcation. As the coupling becomes increasingly local in nature they lose stability through a Hopf bifurcation, giving rise to breathing chimeras, which in turn get destroyed through a homoclinic bifurcation. Remarkably, one of the chimeras reemerges by a reversal...

  8. ALK1 heterozygosity delays development of late normal tissue damage in the irradiated mouse kidney

    International Nuclear Information System (INIS)

    Scharpfenecker, Marion; Floot, Ben; Korlaar, Regina; Russell, Nicola S.; Stewart, Fiona A.

    2011-01-01

    Background and Purpose: Activin receptor-like kinase 1 (ALK1) is a transforming growth factor β (TGF-β) receptor, which is mainly expressed in endothelial cells regulating proliferation and migration in vitro and angiogenesis in vivo. Endothelial cells also express the co-receptor endoglin, which modulates ALK1 effects on endothelial cells. Our previous studies showed that mice with reduced endoglin levels develop less irradiation-induced vascular damage and fibrosis, caused by an impaired inflammatory response. This study was aimed at investigating the role of ALK1 in late radiation toxicity. Material and Methods: Kidneys of ALK +/+ and ALK1 +/- mice were irradiated with 14 Gy. Mice were sacrificed at 10, 20, and 30 weeks after irradiation and gene expression and protein levels were analyzed. Results: Compared to wild type littermates, ALK1 +/- mice developed less inflammation and fibrosis at 20 weeks after irradiation, but displayed an increase in pro-inflammatory and pro-fibrotic gene expression at 30 weeks. In addition, ALK1 +/- mice showed superior vascular integrity at 10 and 20 weeks after irradiation which deteriorated at 30 weeks coinciding with changes in the VEGF pathway. Conclusions: ALK1 +/- mice develop a delayed normal tissue response by modulating the inflammatory response and growth factor expression after irradiation.

  9. Function of skeletal muscle tissue formed after myoblast transplantation into irradiated mouse muscles.

    Science.gov (United States)

    Wernig, A; Zweyer, M; Irintchev, A

    2000-01-15

    1. Pretreatment of muscles with ionising radiation enhances tissue formation by transplanted myoblasts but little is known about the effects on muscle function. We implanted myoblasts from an expanded, male-donor-derived, culture (i28) into X-ray irradiated (16 Gy) or irradiated and damaged soleus muscles of female syngeneic mice (Balb/c). Three to 6 months later the isometric contractile properties of the muscles were studied in vitro, and donor nuclei were visualised in muscle sections with a Y chromosome-specific DNA probe. 2. Irradiated sham-injected muscles had smaller masses than untreated solei and produced less twitch and tetanic force (all by about 18 %). Injection of 106 myoblasts abolished these deficiencies and innervation appeared normal. 3. Cryodamage of irradiated solei produced muscle remnants with few (1-50) or no fibres. Additional myoblast implantation led to formation of large muscles (25 % above normal) containing numerous small-diameter fibres. Upon direct electrical stimulation, these muscles produced considerable twitch (53 % of normal) and tetanic forces (35 % of normal) but innervation was insufficient as indicated by weak nerve-evoked contractions and elevated ACh sensitivity. 4. In control experiments on irradiated muscles, reinnervation was found to be less complete after botulinum toxin paralysis than after nerve crush indicating that proliferative arrest of irradiated Schwann cells may account for the observed innervation deficits. 5. Irradiation appears to be an effective pretreatment for improving myoblast transplantation. The injected cells can even produce organised contractile tissue replacing whole muscle. However, impaired nerve regeneration limits the functional performance of the new muscle.

  10. Lethal effect after whole-body irradiation on mouse with various photon radiations

    International Nuclear Information System (INIS)

    Kohda, Shizuo

    1976-01-01

    The dependence of mortality on the quality of radiation was investigated in ICR mice after wholebody irradiation with 200 kV x-ray, 60 Co γ-ray, or 10 MV x-ray. With respect to the 30 day mortality, LD 50 values were estimated as 606 rad for 200 kV x-ray and as 713 rad both for 60 Co γ-ray and for 10 MV x-ray. Hence, the value of relative biological effectiveness (RBE) to that for 200 kV x-ray was 0.850, while the value decreased with increasing the mortality rate. The value extrapolated to 100% mortality was estimated as 0.6. These results were valid for either 7 or 8 week mice, but the life span of 7 week mice after the irradiation was 3 days shorter than that of 8 week mice. These findings resulted in following conclusions: 1) There are no qualitative differences between 10 MV x-ray and 60 Co γ-ray irradiations. 2) The biological effects after 10 MV x-ray and 60 Co γ-ray irradiations are reduced with increased killing rate, compared with that after 200 kV x-ray irradiations. (Evans, J.)

  11. Effects of misonidazole, irradiation and hyperthermia on lysosomal enzyme activity in mouse tumours

    International Nuclear Information System (INIS)

    Barratt, G.M.; Wills, E.D.

    1981-01-01

    Male C3H mice bearing transplanted tumours were treated with hyperthermia, gamma radiation and the radiosensitising drug misonidazole. The activity of tumour lysosomal acid phosphatase and β-glucuronidase was determined using quantitative cytochemical techniques which measure both lysosomal membrane permeability and enzyme activity. Misonidazole had no effect on the membrane permeability or enzyme activity of tumour lysosomes 1 hr after injection; but 25 hr after the drug treatment the permeability of the lysosomal membrane to the substrate was increased to 1.7 times control. Increases in the lysosomal enzyme activity and membrane permeability were observed 1 hr after combined treatment with misonidazole and irradiation, although neither the drug nor irradiation given alone affected the lysosomes 1 hr after treatment. Twenty-five hours after treatment of tumours with misonidazole given 25 minutes before irradiation of tumours, permeability of the lysosomal membrane had increased to 2.3 times the control. The effects of the irradiation and the radio-sensitisers were thus synergistic. Hyperthermic treatment of tumours increased and misonidazole decreased the lysosomal membrane permeability and enzyme activity measured immediately after exposure. Thus misonidazole and irradiation act synergistically to cause increased lysosomal activity but misonidazole depresses the effect of hyperthermia on lysosomes. (author)

  12. Inhibition of polymerases-alpha and -beta completely blocks DNA repair induced by UV irradiation in cultured mouse neuronal cells

    International Nuclear Information System (INIS)

    Licastro, F.; Sarafian, T.; Verity, A.M.; Walford, R.L.

    1985-01-01

    The effects of hydroxyurea, aphidicolin and dideoxythymidine on UV-induced DNA repair of mouse neuronal granular cells were studied. Aphidicolin, which is considered a specific inhibitor of polymerase-alpha, decreased spontaneous DNA synthesis by 93% and totally suppressed DNA repair. Dideoxythymidine, an inhibitor of polymerase-beta, was more potent in decreasing scheduled DNA synthesis than aphidicolin, and also completely blocked the UV-induced DNA repair. Hydroxyurea, a specific inhibitor of ribonucleotide reductase, inhibited scheduled DNA synthesis, but unscheduled DNA synthesis after UV irradiation was always well detectable. Our data suggest that in neuronal cells from 5 to 10 days old mice both polymerases-alpha and -beta are required for both DNA synthesis and repair. These two enzymes may act jointly in filling up the gaps along the DNA molecule and elongating the DNA chain

  13. Chimera states in Gaussian coupled map lattices

    Science.gov (United States)

    Li, Xiao-Wen; Bi, Ran; Sun, Yue-Xiang; Zhang, Shuo; Song, Qian-Qian

    2018-04-01

    We study chimera states in one-dimensional and two-dimensional Gaussian coupled map lattices through simulations and experiments. Similar to the case of global coupling oscillators, individual lattices can be regarded as being controlled by a common mean field. A space-dependent order parameter is derived from a self-consistency condition in order to represent the collective state.

  14. Basins of Attraction for Chimera States

    DEFF Research Database (Denmark)

    Martens, Erik Andreas; Panaggio, Mark; Abrams, Daniel

    2016-01-01

    Chimera states---curious symmetry-broken states in systems of identical coupled oscillators---typically occur only for certain initial conditions. Here we analyze their basins of attraction in a simple system comprised of two populations. Using perturbative analysis and numerical simulation we...

  15. Developmental abnormalities of the optic nerve head in mouse fetuses caused by simultaneous irradiation of x-rays and ultrasound

    International Nuclear Information System (INIS)

    Shirai, Shoichiro; Yuguchi, Shuji; Majima, Akio.

    1981-01-01

    Eye abnormalities in mouse fetuses caused by irradiation of X-rays alone, or simultaneous irradiation of X-rays and ultrasound on day 7 of gestation were histologically studied on day 18 of gestation. Developmental abnormalities of the optic nerve head were examined in the present experiment, and the following results were obtained: 1. Developmental abnormalities of the optic nerve head associated with developmental abnormalities of the vitreous were detected in 4 fetuses (5 eyes). In all cases, excessive mesenchymal tissue of components of the primary vitreous was found from the optic nerve head to the vitreous cavity. It was impossible to distinguish between the neuroectodermal tissue of Bergmeister's papilla and the mesodermal tissue of components of the primary vitreous. 2. In 3 fetuses (4 eyes), the fetal fissure involving the optic nerve head was open. At the peripapillary region, the inner layer of the optic cup was everted and hyperplastic. The inner neuroblastic layer of the everted portion contacted the outer coat of the eyeball, directly. In these cases, the optic nerve entrance was very wide. 3. The relation between the congenital optic nerve head anomalies encountered clinically and those observed experimentally in the mouse fetuses was discussed. It was considered that the pathogenesis of congenital optic nerve head anomalies consists of the malformation of the primitive epithelial papilla, the faulty closure of the proximal end of the fetal fissure, the anomalies of Bergmeister's papilla, the anomalies of the hyaloid system, or the abnormal differentiation and growth of the neuroectodermal cells of the optic cup. (author)

  16. Sequential analysis of the virus-immune responder characteristics of thymocytes from F1→parent radiation chimeras

    International Nuclear Information System (INIS)

    Korngold, R.; Doherty, P.C.

    1982-01-01

    The virus-immune responder characteristics of thymocytes, spleen and lymph node (LN) cells from (P 1 x P 2 )F 1 →P 1 radiation chimeras have been examined sequentially at weekly intervals. Adoptively-transferred thymocytes generate strong cytotoxic thymus-derived lymphocyte (CTL) responses from 28 to 100 days after reconstitution with bone marrow, which are almost invariably restricted to recognition of virus presented in the context of P 1 . This pattern of H-2 restriction is also maintained for spleen and LN cells from the [(H-2sup(kxd)F 1 →H-2sup(k)] and [(H-2sup(kxb)F 1 →H-2sup(k)] combinations but there is random emergence of reactivity to H-2sup(k)+virus for peripheral lymphoid cells from [(H-2sup(kxb)F 1 →H-2sup(b)] chimeras. Treatment of established [(P 1 xP 2 )]F 1 →P 1 ] chimeras with a low dose of cyclophosphamide (Cy) did not lead to the emergence of significant CTL effector function for P2 + virus. Also, administration of a large dose of Cy prior to irradiation of the chimera recipients did not modify the H-2 restriction profile of the chimera, though the level of CTL responsiveness associated with the appropriate H-2 type was apparently enhanced. (Auth.)

  17. Cell Survival in irradiation mouse intestine is increased by DNA-Binding radioprotectors

    International Nuclear Information System (INIS)

    Coultas, P.; Martin, R.

    1996-01-01

    Crypt survival in the mouse intestine has been used to examine effects of bisbenzimide radioprotectors. Intravenous delivery has been used for the present study in which the effects of methyl proamine (MP), a second generation Hoechst 33342 analogue have been examined. Recent results using the lung model suggest that MP is both more potent as a protector and less toxic than H 33342. The rapid nature of the crypt microcolony survival assay in mouse intestine provides an efficient way to examining factors which could impinge on the extent of radioprotection, for example, the interval between protector administration and radiation exposure. The data clearly show that for MP at 100 mg/kg, there is substantially increased crypt survival equivalent to a dose modification of about 1.33. The crypt scoring methods used indicate that protection is throughout the small intestine and preliminary data indicate that colon is also protected to a similar or slightly greater extent

  18. Phenotypic characterization of early events of thymus repopulation in radiation bone marrow chimeras

    International Nuclear Information System (INIS)

    Sharrow, S.O.; Singer, A.; Hammerling, U.; Mathieson, B.J.

    1983-01-01

    The phenotype of murine thymocytes repopulating the thymus of radiation bone marrow chimeras shortly after irradiation and bone marrow reconstitution was analyzed by immunofluorescence and flow microfluorometry. Thymuses in these chimeras, while essentially devoid of lymphoid cells at day 7, were repopulated by days 10 to 12 after irradiation. It was found that this initial repopulation arose from a radioresistant intrathymic precursor that expanded to an almost complete complement of host-type thymocytes. However, these host-derived thymocytes were unusual in that they were relatively deficient in Lyt 1+2- and peanut agglutinin ''dull'' cells as compared with normal thymocytes. Donor bone-marrow-derived cells first appeared in the irradiated chimeric thymuses between days 12 and 15 after irradiation and bone marrow transfer. By day 19, chimeric thymuses contained more than 98% donor cells. This course was identical for three chimeric combinations, each made across different genetic barriers. In contrast to the cells that populate the fetal thymus during normal ontogeny, the first donor bone-marrow-derived cells that can be detected within the irradiated chimeric thymuses already expressed phenotypically normal adult T cell subpopulations in that they contained significant numbers both of Lyt 1+2- and of Lyt 1+2+ thymocytes. Thus, the Lyt phenotype of donor cells that initially repopulate an adult thymus after irradiation is markedly different from the Lyt phenotype of cells that initially populate the fetal thymus. The differences between adult and fetal thymic development that are observed in radiation bone marrow chimeras may be important in our understanding of T cell differentiation in these animals

  19. Age-related effects of X-ray irradiation on mouse hippocampus

    DEFF Research Database (Denmark)

    Casciati, Arianna; Dobos, Katalin; Antonelli, Francesca

    2016-01-01

    Therapeutic irradiation of pediatric and adult patients can profoundly affect adult neurogenesis, and cognitive impairment manifests as a deficit in hippocampal-dependent functions. Age plays a major role in susceptibility to radiation, and younger children are at higher risk of cognitive decay w...

  20. Influence of cysteamine and a mixture of radioprotectors on polynucleates and lymphocytes in irradiated mouse

    International Nuclear Information System (INIS)

    Fatome, M.; Bernard, P.

    The diminution of the number of peripheral blood white elements is one of the consequences of ionizing radiation action on organism, even at sublethal doses. The drop of these white elements and their possible recovery in irradiated animal, which have received before a radioprotective substance, are studied. The results ontained are compared with these found in non-protected animal [fr

  1. Immunological activity of the mouse splencytes at a later period after irradiation

    International Nuclear Information System (INIS)

    Samojlovich, M.P.; Klimovich, V.B.

    1981-01-01

    CBA and A/Sn mice that had lived for 2-20 months after sublethal irradiation and intact species of the same age were immunized intravenously with the male sheep erythrocytes. The quantity of the antibody forming cells (AFC) in the spleen decreased in 2 or 3.5 months after the irradiation; in 5 or 8 months it did not differ from the normal and in 13 months it decreased again advancing against the similar age shift in the intact group. The same dynamics was observed when investigating the immune response of a standard number of the experimental mice spleen cells in the adaptive transfer system. In periods, when the immune response of irradiated (2 and 200 months after exposure) or intact (aged 20 or 24 months) mice diminished, the quantity of the AFC cells generated adaptively by transferred spleen cells did not practically depend on the quantity of the transplant's cells. The transplantation of the spleen cells of old irradiated or intact mice in a mixture with splenocytes of young intact donors led to the suppression of immune reactions of normal cells. On the basis of the data obtained the conclusion was made that the late radiation immunodepression was primarily caused by functional defects of the immunocompetent cells and not by their numeric deficit

  2. Schistosoma mansoni: migration and attrition of irradiated and challenge schistosomula in the mouse

    Energy Technology Data Exchange (ETDEWEB)

    Mastin, A.J.; Wilson, R.A. (York Univ. (UK)); Bickle, Q.D. (Winches Farm Field Station, St. Albans (UK))

    1983-08-01

    The fate of irradiated, immunizing cercariae and challenge schistosomula was investigated in mice using a quantitative, histological technique which would appear to be more efficient in estimating parasite numbers in skin and lungs than does the tissue mincing and incubation recovery technique used previously by other workers. There was evidence for slight retardation of irradiated parasite migration in skin, but death of schistosomula in the skin appeared negligible. The majority of irradiated parasites remained in the lungs until at least day 21 after infection, and that most schistosomula observed at this time were dead. In mice immunized with irradiated cercariae there was no evidence of attrition of the challenge infection in the skin. The migration profile of challenge parasites in the lungs of immunized animals was not significantly different from that of normal parasites in the lungs of naive animals. Dead challenge parasites were observed in the lungs but their numbers were not considered great enough to account for the final attrition measured by perfusion. It is suggested that the remainder of the attrition of challenge schistosomula may occur in the systemic and/or hepatic portal circulation.

  3. Schistosoma mansoni: migration and attrition of irradiated and challenge schistosomula in the mouse

    International Nuclear Information System (INIS)

    Mastin, A.J.; Wilson, R.A.; Bickle, Q.D.

    1983-01-01

    The fate of irradiated, immunizing cercariae and challenge schistosomula was investigated in mice using a quantitative, histological technique which would appear to be more efficient in estimating parasite numbers in skin and lungs than does the tissue mincing and incubation recovery technique used previously by other workers. There was evidence for slight retardation of irradiated parasite migration in skin, but death of schistosomula in the skin appeared negligible. The majority of irradiated parasites remained in the lungs until at least day 21 after infection, and that most schistosomula observed at this time were dead. In mice immunized with irradiated cercariae there was no evidence of attrition of the challenge infection in the skin. The migration profile of challenge parasites in the lungs of immunized animals was not significantly different from that of normal parasites in the lungs of naive animals. Dead challenge parasites were observed in the lungs but their numbers were not considered great enough to account for the final attrition measured by perfusion. It is suggested that the remainder of the attrition of challenge schistosomula may occur in the systemic and/or hepatic portal circulation. (author)

  4. Response of mouse lung to irradiation at different dose-rates

    International Nuclear Information System (INIS)

    Hill, R.P.

    1983-01-01

    Groups of LAF1 mice were given thoracic irradiation using 60 Co γ-rays at dose-rates of 0.05 Gy/min (LDR) or 1.1 Gy/min (HDR) and the death of the animals was monitored as a function of time. It was found that the time pattern of animal deaths was similar for the two different dose-rates. Dose response curves for animals dying at various times up to 500 days after irradiation were calculated and the LD 50 values determined. The curves for the LD 50 values, plotted as a function of the time at analysis for treatment at HDR or LDR, were essentially parallel to each other but separated by a factor (LDR/HDR) of about 1.8. This indicates that the sparing effect of LDR treatment is the same for deaths occurring during the early pneumonitis phase or during the late fibrotic phase of lung damage. The available information on the response of patients to whole thoracic irradiation, given for either palliation or piror to bone marrow transplantation, suggests that for similar dose-rates to those studied here the ratio (LDR/HDR) is only 1.2 to 1.3. This difference between the animal and human data may reflect the modifying effect of the large doses of cytotoxic drugs used in combination with the irradiation of bone marrow transplant patients

  5. Quantitative study of late injury in the irradiated mouse lung using computer graphics

    International Nuclear Information System (INIS)

    Tanabe, Masahiro; Furuse, Takeshi; Rapachietta, D.R.; Kallman, R.F.

    1990-01-01

    It is reported that quantitative histological analysis using current imaging technology and computer graphics is useful in studying late injury in the irradiated lung (with and without added chemotherapy), and that it correlated closely with results of the functional breathing rate test. (author). 7 refs.; 1 fig

  6. Effects of bone marrow or mesenchymal stem cell transplantation on oral mucositis (mouse) induced by fractionated irradiation

    International Nuclear Information System (INIS)

    Schmidt, M.; Haagen, J.; Noack, R.; Siegemund, A.; Gabriel, P.; Doerr, W.

    2014-01-01

    Oral mucositis is a severe and dose limiting early side effect of radiotherapy for head-and-neck tumors. This study was initiated to determine the effect of bone marrow- and mesenchymal stem cell transplantation on oral mucositis (mouse tongue model) induced by fractionated irradiation. Daily fractionated irradiation (5 x 3 Gy/week) was given over 1 (days 0-4) or 3 weeks (days 0-4, 7-11, 14-18). Each protocol was terminated (day 7 or 21) by graded test doses (5 dose groups, 10 animals each) in order to generate complete dose-effect curves. The incidence of mucosal ulceration, corresponding to confluent mucositis grade 3 (RTOG/EORTC), was analyzed as the primary, clinically relevant endpoint. Bone marrow or mesenchymal stem cells were transplanted intravenously at various time points within these fractionation protocols. Transplantation of 6 x 10 6 , but not of 3 x 10 6 bone marrow stem cells on day -1, +4, +8, +11 or +15 significantly increased the ED 50 values (dose, at which an ulcer is expected in 50% of the mice); transplantation on day +2, in contrast, was ineffective. Mesenchymal stem cell transplantation on day -1, 2 or +8 significantly, and on day +4 marginally increased the ED 50 values. Transplantation of bone marrow or mesenchymal stem cells has the potential to modulate radiation-induced oral mucositis during fractionated radiotherapy. The effect is dependent on the timing of the transplantation. The mechanisms require further investigation. (orig.)

  7. Histological examination of the effect of differently fractionated irradiations in rat and mouse organs. Pt. 3

    International Nuclear Information System (INIS)

    Unger, E.

    1984-01-01

    The spleen of rats was irradiated with 50 Gy dose local X-rays in two different fractionation rhythms, i.e. twice a week given high and daily applied lower fractions of radiation. According to the results of 3 H-thymidine autoradiography made after the last irradiation 24 hours later both in the white and the red pulp the labelling index was less on the effect of twice in a week applied high radiation fractions than in case of daily given lower fractions. This indicate in correlation with the results of earlier analogous histological experiments that the damaging effect of rarely given higher fractions of radiation in the spleen is especially obvious. (orig.) [de

  8. Suppressor cells in transplantation tolerance II. Maturation of suppressor cells in the bone marrow chimera

    International Nuclear Information System (INIS)

    Tutschka, P.J.; Ki, P.F.; Beschorner, W.E.; Hess, A.D.; Santos, G.W.

    1981-01-01

    Histoincompatible bone marrow allografts were established in lethally irradiated rats. At various times after transplantation, the spleen cells were harvested, subjected to mixed lymphocyte cultures, and assayed for suppressor cells in vitro and in vivo by adoptive transfer studies. Alloantigen-nonspecific suppressor cells appeared in the chimera at 40 days after grafting, coinciding with the resolution of graft-versus-host disease (GVHD). At 250 days the nonspecific suppressor cells were replaced by suppressor cells specifically suppressing donor-versus-host alloantigen responses. At 720 days suppressor cells could no longer be identified by in vitro methods but were identified by in vivo adoptive transfer of transplantation tolerance. After injection of host-type antigen into chimeras, the suppressor cells could be again demonstrated by in vitro methods

  9. Suppressor cells in transplantation tolerance. II. maturation of suppressor cells in the bone marrow chimera

    International Nuclear Information System (INIS)

    Tutschka, P.J.; Ki, P.F.; Beschorner, W.E.; Hess, A.D.; Santos, G.W.

    1981-01-01

    Histoincompatible bone marrow allografts were established in lethally irradiated rats. At various times after transplantation, the spleen cells were harvested, subjected to mixed lymphocyte cultures, and assayed for suppressor cells in vitro and in vivo by adoptive transfer studies. Alloantigen-nonspecific suppressor cells appeared in the chimera at 40 days after grafting, coinciding with the resolution of graft-versus-host disease (GVHD). At 250 days the nonspecific suppressor cells were replaced by suppressor cells specifically suppressing donor-versus-host alloantigen responses. At 720 days suppressor cells could no longer be identified by in vitro methods but were identified by in vivo adoptive transfer of transplantation tolerance. After injection of host-type antigen into chimeras, the suppressor cells could be again demonstrated by in vitro methods

  10. Late vascular effects of whole brain X-irradiation in the mouse

    Energy Technology Data Exchange (ETDEWEB)

    Yoshii, Y [Tsukuba Univ., Sakma, Ibaraki (Japan). Inst. of Clinical Medicine; Phillips, T L [California Univ., San Francisco (USA). Dept. of Radiation Oncology

    1982-01-01

    The whole brains of mice were irradiated with 250kVp X-rays at 120 rads min/sup -1/ (1.6 mm Cu HVL, TSD 50 cm), and a histological study was carried out. The dose range of X-irradiation was from 1,300 to 2,500 rads, i.e., 1,300, 1,500, 1,750, 2,000, and 2,500 rads. Eighty-six mice were used for histological examination. For microscopic examination, the mice were killed at regular postirradiation intervals between 15 and 20, 31 and 40, 41 and 50, 51 and 60, 61 and 70, 71 and 80, 81 and 90, 139 and 177 weeks. The brains were removed immediately thereafter, fixed in Bouin's solution, and embedded in paraffin. A histological examination was performed by a morphometric estimation of vascular lesions, in which the degree of the damage to the arterial system was scored in whole serial brain section. Necrosis (encephalomalacia), atrophy, cell infiltration, and telangiectactic vascular change of the brain, caused as a result of the fibrinoid necrosis of the large arteries, were observed. Dose-dependent incidence of the fibrinoid necrosis increased between 41 and 87 weeks after irradiation. Mean score of fibrinoid necrosis increased dose dependently approximately 60 weeks after irradiation. It is suggested that scores of large vessel damage do relate to dose at 41 to 87 weeks, and can be used to quantify the vessel injury, and that fibrinoid necrosis of the large vessels may relate to the incidence of radionecrosis.

  11. Late vascular effects of whole brain X-irradiation in the mouse

    International Nuclear Information System (INIS)

    Yoshii, Y.; Phillips, T.L.

    1982-01-01

    The whole brains of mice were irradiated with 250kVp X-rays at 120 rads min -1 (1.6 mm Cu HVL, TSD 50 cm), and a histological study was carried out. The dose range of X-irradiation was from 1,300 to 2,500 rads, i.e., 1,300, 1,500, 1,750, 2,000, and 2,500 rads. Eighty-six mice were used for histological examination. For microscopic examination, the mice were killed at regular postirradiation intervals between 15 and 20, 31 and 40, 41 and 50, 51 and 60, 61 and 70, 71 and 80, 81 and 90, 139 and 177 weeks. The brains were removed immediately thereafter, fixed in Bouin's solution, and embedded in paraffin. A histological examination was performed by a morphometric estimation of vascular lesions, in which the degree of the damage to the arterial system was scored in whole serial brain section. Necrosis (encephalomalacia), atrophy, cell infiltration, and telangiectactic vascular change of the brain, caused as a result of the fibrinoid necrosis of the large arteries, were observed. Dose-dependent incidence of the fibrinoid necrosis increased between 41 and 87 weeks after irradiation. Mean score of fibrinoid necrosis increased dose dependently approximately 60 weeks after irradiation. It is suggested that scores of large vessel damage do relate to dose at 41 to 87 weeks, and can be used to quantify the vessel injury, and that fibrinoid necrosis of the large vessels may relate to the incidence of radionecrosis. (Author)

  12. Effects of follicle stimulationg hormone on {gamma}-ray irradiated immature mouse ovarian follicles

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jin Kyu; Lee, Chang Joo; Lee, Young Keun [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of); Song, Kang Won; Yoon, Yong Dal [Hanyang Univ., Seoul (Korea, Republic of)

    1998-06-01

    To assess the radioprotective effects of Follicle Stimulating Hormone (FSH) on ovarian follicles, 3 week-old female mice were irradiated with 8.33 Gy of {gamma}-ray (group R) and followed by 5 IU ip-injection of FSH (group RF). For control groups, 5 IU of saline (group C) or 5 IU of FSH (group F) was ip-injected. Ovaries were collected 0h, 6h, 12h, 1d, 2d, 4d, and 8d after irradiation or saline/FSH injection, and followed by fixation in neutral buffered formalin for routine histochemistry. Immunohistochemistry was used to assess the status of follicles and DNA fragmentation was analyzed by agarose gel electrophoresis for total DNA. Staining specific for apoptotic follicles showed high intensity at 6h and 12h in group R and RF. On the other hand, staining specific for proliferating follicles showed noticeably high intensity at 8d in group R and RF. DNA fragmentation of 185bp increased with time in all experimental groups. Especially 370bp appeared at 6h in group R, then disappeared after 1d. In case of group RF, it appeared at 12h and disappeared after 1d. From the above results, the irradiated antral follicles become completely disappeared from 4d to 8d, and then new follicles started to grow again at 8d. FSH had delaying or suppressing effects on follicular atresia after irradiation. In addition, it became clear that radiation-induced follicular atresia was mediated by granulosa cell apoptosis.

  13. The re-establishment of hypersensitive cells in the crypts of irradiated mouse intestine

    International Nuclear Information System (INIS)

    Ijiri, K.; Potten, C.S.

    1984-01-01

    Two doses of γ-radiation separated by various time intervals have been used to investigate when after irradiation the cell population susceptible to acute cell death is re-established. Dead cells were scored 3 or 6 h after the second dose. Within 1-2 days of small doses (0.5 Gy) the sensitive cells, recognized histologically as apoptotic cells, are re-established at the base of the crypt (around cell position 6). After higher doses (9.0 Gy) they are not re-established until about the fourth day after irradiation. Even in the enlarged regenerating crypts the sensitive cells are found at the same position at the crypt base. It has been estimated that the crypt contains five or six cells that are susceptible to low doses (0.5 Gy) (hypersensitive cells) and up to a total of only seven or eight susceptible cells that can be induced by any dose to enter the sequence of changes implicit in apoptosis. Between 4 and 10 days after an intitial irradiation of 9.0 Gy the total number of susceptible cells increased from seven to eight to about 10 to 13 per crypt. (author)

  14. Optimization of monoclonal antibody production in mouse ascites by single whole-body irradiation

    International Nuclear Information System (INIS)

    Witt, S.; Ziegler, B.; Kloeting, I.; Ziegler, M.; Nadrowitz, R.; Schmidt, W.

    1987-01-01

    Hybridoma cells injected intraperitoneally into mice induce formation of ascites tumors producing ascites fluid with high levels of monoclonal antibodies. Several parameters affect the growth of the immunoglobulin-producing tumors in vivo. In 10 different hybridomas the average ascites tumor formation rate could be increased from 32% (n = 338 mice) to 77% (n = 112 mice) by only one whole-body irradiation of paraffin-pretreated Balb/c mice. Production of monoclonal antibodies was better in males because of the significantly (p < 0.01) increased volume of ascites fluid. From the increased tumor formation rate in irradiated mice it is suggested that in non-irradiated recipients the tumor growth rate was lowered by immunological reactions against hybridoma cells provoked by cell surface neoantigens revealed by cell fusion and/or tumor-associated antigens of the myeloma parent cells as well as by altered antigen pattern caused by possible mutations in the myeloma cell line and/or Balb/c/K strain. (author)

  15. Differential effects of whole-body {gamma}-irradiation on antinociception induced by morphine and {beta}-endorphin administered intracerebroventricularly in the mouse

    Energy Technology Data Exchange (ETDEWEB)

    Kim, J.K. [Korea Atomic Energy Research Inst., Taejon (Korea, Republic of); Chung, K.M.; Park, T.W.

    2000-05-01

    Two separate lines of evidence suggested the present study. First, intracerebroventricularly (i.c.v.) administered morphine (a {mu}-opioid receptor agonist) and {beta}-endorphin (an {epsilon}-opioid receptor agonist) produce antinociception by activating different descending pain inhibitory systems. Second, {gamma}-irradiation attenuates the acute antinociceptive action of i.c.v. injected morphine, but not DPLPE (a {delta}-opioid receptor agonist), in mice. These findings prompted us to investigate the effect of {gamma}-irradiation on the antinociception produced by i.c.v. injected morphine and {beta}-endorphin in male ICR mice. In one group, mice were exposed to whole-body irradiation at a dose of 5 Gy from a {sup 60}Co {gamma}-source and the antinociceptive effects were tested 5, 30, 60,90 and 180 min after irradiation using the 1% acetic acid-induced writhing test (10 ml/kg). The antinociceptive effect was produced time-dependently and reached its maximum at 90 min after irradiation. Thus, time was fixed in the following studies. In another group, mice were irradiated with 5 Gy and tested 90 minutes later for antinociception produced by i.c.v. administration of morphine (50 and 100 ng/mouse) or {beta}-endorphin (31 ng/mouse). Irradiation significantly potentiated the antinociception produced by {beta}-endorphin. However, the antinociception produced by morphine was not affected by irradiation. These results demonstrate a differential sensitivity of {mu}- and {epsilon}-opioid receptors to {gamma}-irradiation, in addition, support the hypothesis that morphine and {beta}-endorphin administered supraspinally produce antinociception by different neuronal mechanisms. (author)

  16. Differential effects of whole-body γ-irradiation on antinociception induced by morphine and β-endorphin administered intracerebroventricularly in the mouse

    International Nuclear Information System (INIS)

    Kim, J.K.; Chung, K.M.; Park, T.W.

    2000-01-01

    Two separate lines of evidence suggested the present study. First, intracerebroventricularly (i.c.v.) administered morphine (a μ-opioid receptor agonist) and β-endorphin (an ε-opioid receptor agonist) produce antinociception by activating different descending pain inhibitory systems. Second, γ-irradiation attenuates the acute antinociceptive action of i.c.v. injected morphine, but not DPLPE (a δ-opioid receptor agonist), in mice. These findings prompted us to investigate the effect of γ-irradiation on the antinociception produced by i.c.v. injected morphine and β-endorphin in male ICR mice. In one group, mice were exposed to whole-body irradiation at a dose of 5 Gy from a 60 Co γ-source and the antinociceptive effects were tested 5, 30, 60,90 and 180 min after irradiation using the 1% acetic acid-induced writhing test (10 ml/kg). The antinociceptive effect was produced time-dependently and reached its maximum at 90 min after irradiation. Thus, time was fixed in the following studies. In another group, mice were irradiated with 5 Gy and tested 90 minutes later for antinociception produced by i.c.v. administration of morphine (50 and 100 ng/mouse) or β-endorphin (31 ng/mouse). Irradiation significantly potentiated the antinociception produced by β-endorphin. However, the antinociception produced by morphine was not affected by irradiation. These results demonstrate a differential sensitivity of μ- and ε-opioid receptors to γ-irradiation, in addition, support the hypothesis that morphine and β-endorphin administered supraspinally produce antinociception by different neuronal mechanisms. (author)

  17. Chimera states in nonlocally coupled phase oscillators with biharmonic interaction

    Science.gov (United States)

    Cheng, Hongyan; Dai, Qionglin; Wu, Nianping; Feng, Yuee; Li, Haihong; Yang, Junzhong

    2018-03-01

    Chimera states, which consist of coexisting domains of coherent and incoherent parts, have been observed in a variety of systems. Most of previous works on chimera states have taken into account specific form of interaction between oscillators, for example, sinusoidal coupling or diffusive coupling. Here, we investigate chimera dynamics in nonlocally coupled phase oscillators with biharmonic interaction. We find novel chimera states with features such as that oscillators in the same coherent cluster may split into two groups with a phase difference around π/2 and that oscillators in adjacent coherent clusters may have a phase difference close to π/2. The different impacts of the coupling ranges in the first and the second harmonic interactions on chimera dynamics are investigated based on the synchronous dynamics in globally coupled phase oscillators. Our study suggests a new direction in the field of chimera dynamics.

  18. The chimera state in colloidal phase oscillators with hydrodynamic interaction

    Science.gov (United States)

    Hamilton, Evelyn; Bruot, Nicolas; Cicuta, Pietro

    2017-12-01

    The chimera state is the incongruous situation where coherent and incoherent populations coexist in sets of identical oscillators. Using driven non-linear oscillators interacting purely through hydrodynamic forces at low Reynolds number, previously studied as a simple model of motile cilia supporting waves, we find concurrent incoherent and synchronised subsets in small arrays. The chimeras seen in simulation display a "breathing" aspect, reminiscent of uniformly interacting phase oscillators. In contrast to other systems where chimera has been observed, this system has a well-defined interaction metric, and we know that the emergent dynamics inherit the symmetry of the underlying Oseen tensor eigenmodes. The chimera state can thus be connected to a superposition of eigenstates, whilst considering the mean interaction strength within and across subsystems allows us to make a connection to more generic (and abstract) chimeras in populations of Kuramoto phase oscillators. From this work, we expect the chimera state to emerge in experimental observations of oscillators coupled through hydrodynamic forces.

  19. Clustered chimera states in systems of type-I excitability

    International Nuclear Information System (INIS)

    Vüllings, Andrea; Omelchenko, Iryna; Hövel, Philipp; Hizanidis, Johanne

    2014-01-01

    The chimera state is a fascinating phenomenon of coexisting synchronized and desynchronized behaviour that was discovered in networks of nonlocally coupled identical phase oscillators over ten years ago. Since then, chimeras have been found in numerous theoretical and experimental studies and more recently in models of neuronal dynamics as well. In this work, we consider a generic model for a saddle-node bifurcation on a limit cycle representative of neural excitability type I. We obtain chimera states with multiple coherent regions (clustered chimeras/multi-chimeras) depending on the distance from the excitability threshold, the range of nonlocal coupling and the coupling strength. A detailed stability diagram for these chimera states and other interesting coexisting patterns (like traveling waves) is presented. (paper)

  20. Chronic graft-versus-host disease in the rat radiation chimera. III. Immunology and immunopathology in rapidly induced models

    International Nuclear Information System (INIS)

    Beschorner, W.E.; Tutschka, P.J.; Santos, G.W.

    1983-01-01

    Although chronic graft-versus-host disease (GVHD) frequently develops in the long-term rat radiation chimera, we present three additional models in which a histologically similar disease is rapidly induced. These include adoptive transfer of spleen and bone marrow from rats with spontaneous chronic GVHD into lethally irradiated rats of the primary host strain; sublethal irradiation of stable chimeras followed by a booster transplant; and transfer of spleen cells of chimeras recovering from acute GVHD into second-party (primary recipient strain) or third-party hosts. Some immunopathologic and immune abnormalities associated with spontaneous chronic GVHD were not observed in one or more of the induced models. Thus, IgM deposition in the skin, antinuclear antibodies, and vasculitis appear to be paraphenomena. On the other hand, lymphoid hypocellularity of the thymic medulla, immaturity of splenic follicles, and nonspecific suppressor cells were consistently present in the long term chimeras, and in all models. These abnormalities therefore may be pathogenetically important, or closely related to the development of chronic GVHD

  1. Restricted antibody formation to sheep erythrocytes of allogeneic bone marrow chimeras histoincompatible at the K end of the H-2 complex

    International Nuclear Information System (INIS)

    Onoe, K.; Yasumizu, R.; Oh-Ishi, T.; Kakinuma, M.; Good, R.A.; Morikawa, K.

    1981-01-01

    Employing a new method for allogeneic bone marrow transplantation, irradiation chimeras constructed from various combinations of marrow cells from B10 H-2 recombinant mice and AKR recipients were prepared. Though these chimeras had well-developed populations of T and B cells, they showed strikingly different patterns of responses in the primary antibody formation to sheep erythrocytes (SRBC), a T dependent antigen. These are (a) AKR mice treated with C57BL/10 cells, [B10 leads to AKR] fully H-2 incompatible, and AKR mice treated with B10.A (5R) cells, [5R leads to AKR] I-J,E compatible chimeras that were almost completely unresponsive to SRBC; (b) AKR mice treated with B10.BR cells [BR leads to AKR] fully H-2 compatible, and AKR mice treated with B10 AKM cells, [AKM leads to AKR] chimeras where donor and recipient differed only at H-2D, showed the same number of plaque-forming cells (PFC) as B10 control mice; (c) AKR mice treated with B10.A cells, [B10 leads to AKR] chimeras, where donor and recipient were matched at H-2K-I-E region, showed about one-half the number of PFC as the control mice. From these results we conclude that in allogeneic bone marrow chimeras primary antibody response to T-dependent antigen, such as SRBC, is generated when at least the K end of the H-2 complex is compatible between donor and recipient

  2. Persistent chimera states in nonlocally coupled phase oscillators

    OpenAIRE

    Suda, Yusuke; Okuda, Koji

    2015-01-01

    Chimera states in the systems of nonlocally coupled phase oscillators are considered stable in the continuous limit of spatially distributed oscillators. However, it is reported that in the numerical simulations without taking such limit, chimera states are chaotic transient and finally collapse into the completely synchronous solution. In this Rapid Communication, we numerically study chimera states by using the coupling function different from the previous studies and obtain the result that...

  3. Preliminary results of Digital Pulse Shape Acquisition from Chimera

    Energy Technology Data Exchange (ETDEWEB)

    Alderighi, D.M.; Sechi, G. [INFN Milano and IASF, CNR, Milano (France); Anzalone, A.; Cavallaro, S.; Giustolisi, F.; Laguidara, E.; Lanzalone, G.; Porto, F. [Catania Univ., LNS and Dipartimento di Fisica (France); Bassini, R.; Boiano, C.; Guazzoni, P.; Russo, S.; Sassi, M.; Zetta, L. [Milano Univ., INFN and Dipartimento di Fisica (Italy); Cardella, G.; Defilippo, S.E.; Lanzano, G.; Paganod, A.; Papa, M.; Pirrone, S.; Politi, G. [Catania Univ., INFN and Dipartimento di Fisica (Italy); Geraci, E. [Bologna Univ., INFN and Dipartimento di Fisica (Italy)

    2003-07-01

    A 100 MS/s 14-bit Sampling Analog-to-Digital converter has been used to perform digital pulse-shape acquisition of signals collected from CHIMERA telescopes. The signals from a typical CHIMERA detection cell have been collected using both a standard CHIMERA electronic chain up to the amplifier, and a very simple analog front end, basically reduced to the preamplifier. The preliminary on-beam results are presented. (authors)

  4. Breathing chimera in a system of phase oscillators

    Science.gov (United States)

    Bolotov, M. I.; Smirnov, L. A.; Osipov, G. V.; Pikovsky, A. S.

    2017-09-01

    Chimera states consisting of synchronous and asynchronous domains in a medium of nonlinearly coupled phase oscillators have been considered. Stationary inhomogeneous solutions of the Ott-Antonsen equation for a complex order parameter that correspond to fundamental chimeras have been constructed. The direct numerical simulation has shown that these structures under certain conditions are transformed to oscillatory (breathing) chimera regimes because of the development of instability.

  5. Preliminary results of Digital Pulse Shape Acquisition from Chimera

    International Nuclear Information System (INIS)

    Alderighi, D.M.; Sechi, G.; Anzalone, A.; Cavallaro, S.; Giustolisi, F.; Laguidara, E.; Lanzalone, G.; Porto, F.; Bassini, R.; Boiano, C.; Guazzoni, P.; Russo, S.; Sassi, M.; Zetta, L.; Cardella, G.; Defilippo, S.E.; Lanzano, G.; Paganod, A.; Papa, M.; Pirrone, S.; Politi, G.; Geraci, E.

    2003-01-01

    A 100 MS/s 14-bit Sampling Analog-to-Digital converter has been used to perform digital pulse-shape acquisition of signals collected from CHIMERA telescopes. The signals from a typical CHIMERA detection cell have been collected using both a standard CHIMERA electronic chain up to the amplifier, and a very simple analog front end, basically reduced to the preamplifier. The preliminary on-beam results are presented. (authors)

  6. Response of developing mouse liver irradiated in utero and its modification by 2-mercaptopropionylglycine

    International Nuclear Information System (INIS)

    Pareek, B.P.; Mehta, G.; Bhartiya, H.C.; Dev, P.K.

    1983-01-01

    Pregnant Swiss albino mice were exposed at gestation days 14.25, 16.25 and 18.25 to 1.5 Gy gamma radiation from 60 Co in the presence or absence of 2-mercaptopropionylglycine (MPG). Liver was taken from the litters born to these mothers at different post-partum intervals. The maximum sensitivity was found in 4-week-old animals irradiated at gestation day 14.25. In the MPG treated groups, the number of total cells was higher than in the controls but less than in normals. The increase in pyknotic nuclei and necrotic and binucleate cells was significantly lowered by MPG. (Auth.)

  7. Chimera States in Mechanical Oscillator Networks

    OpenAIRE

    Martens, Erik Andreas; Thutupalli, Shashi; Fourrière, Antoine; Hallatschek, Oskar

    2013-01-01

    The synchronization of coupled oscillators is a fascinating manifestation of self-organization that nature uses to orchestrate essential processes of life, such as the beating of the heart. Although it was long thought that synchrony and disorder were mutually exclusive steady states for a network of identical oscillators, numerous theoretical studies in recent years have revealed the intriguing possibility of “chimera states,” in which the symmetry of the oscillator population is broken into...

  8. Photocarcinogenesis and persistent hyperplasia in UV-irradiated SENCAR mouse skin

    International Nuclear Information System (INIS)

    Strickland, P.T.

    1986-01-01

    Susceptibility to photocarcinogenesis has been examined in several mouse strains and stocks including SENCAR, CD-1, BALB/c, C3H, C57Bl, and NZB. SENCAR mice are hypersusceptible to tumorigenesis caused by single high dose exposures to ultraviolet (UV) radiation but not by chronic low-dose exposures. SENCAR mice also exhibit an exaggerated and persistent epidermal hyperplasia in response to UV-induced tissue damage. The persistent hyperplasia is apparently due to a sustained proliferation of the epithelial basal cells, rather than to delayed cell differentiation. SENCAR mice did not exhibit persistent hyperplasia following other forms of tissue damage (surgical or thermal). In related studies, the levels of thymine dimers induced in SENCAR epidermis by UV radiation were comparable to those observed in BALB/c epidermis. In addition, no differences were found in the tissue distribution or persistence of thymine dimers in SENCAR and BALB/c skin

  9. Dominant lethal mutations and histological changes produced in mouse oocytes by gamma irradiation

    International Nuclear Information System (INIS)

    Vyglenov, A.; Baev, I.; Rupova, I.; Kusheva, R.

    1976-01-01

    Mouse female were exposed to a total dose of 500 or 1000 rad 137 Cs gamma rays delivered at 0.01 rad/min. Effects were scored at 1, 5, 7, and 10 weeks after cessation of treatment. Histologically, ovaria in the 500 rad group showed a decrease up to 11% in follicle numbers as compared to controls; with the prolongation of the time after exposure, a further fall in follicle numbers is observed. In the 1000 rad group, depopulation of ovaria was complete. With the 500 rad dose, total dominant lethality was found to be increased for any of the time intervals between radiation exposure and conception; postimplantation dominant lethality was comparatively low, with similar scores between the weeks investigated. (author)

  10. Computing Flows Using Chimera and Unstructured Grids

    Science.gov (United States)

    Liou, Meng-Sing; Zheng, Yao

    2006-01-01

    DRAGONFLOW is a computer program that solves the Navier-Stokes equations of flows in complexly shaped three-dimensional regions discretized by use of a direct replacement of arbitrary grid overlapping by nonstructured (DRAGON) grid. A DRAGON grid (see figure) is a combination of a chimera grid (a composite of structured subgrids) and a collection of unstructured subgrids. DRAGONFLOW incorporates modified versions of two prior Navier-Stokes-equation-solving programs: OVERFLOW, which is designed to solve on chimera grids; and USM3D, which is used to solve on unstructured grids. A master module controls the invocation of individual modules in the libraries. At each time step of a simulated flow, DRAGONFLOW is invoked on the chimera portion of the DRAGON grid in alternation with USM3D, which is invoked on the unstructured subgrids of the DRAGON grid. The USM3D and OVERFLOW modules then immediately exchange their solutions and other data. As a result, USM3D and OVERFLOW are coupled seamlessly.

  11. A New Approximate Chimera Donor Cell Search Algorithm

    Science.gov (United States)

    Holst, Terry L.; Nixon, David (Technical Monitor)

    1998-01-01

    The objectives of this study were to develop chimera-based full potential methodology which is compatible with overflow (Euler/Navier-Stokes) chimera flow solver and to develop a fast donor cell search algorithm that is compatible with the chimera full potential approach. Results of this work included presenting a new donor cell search algorithm suitable for use with a chimera-based full potential solver. This algorithm was found to be extremely fast and simple producing donor cells as fast as 60,000 per second.

  12. Chimera states in networks of logistic maps with hierarchical connectivities

    Science.gov (United States)

    zur Bonsen, Alexander; Omelchenko, Iryna; Zakharova, Anna; Schöll, Eckehard

    2018-04-01

    Chimera states are complex spatiotemporal patterns consisting of coexisting domains of coherence and incoherence. We study networks of nonlocally coupled logistic maps and analyze systematically how the dilution of the network links influences the appearance of chimera patterns. The network connectivities are constructed using an iterative Cantor algorithm to generate fractal (hierarchical) connectivities. Increasing the hierarchical level of iteration, we compare the resulting spatiotemporal patterns. We demonstrate that a high clustering coefficient and symmetry of the base pattern promotes chimera states, and asymmetric connectivities result in complex nested chimera patterns.

  13. Time-delayed feedback control of coherence resonance chimeras

    Science.gov (United States)

    Zakharova, Anna; Semenova, Nadezhda; Anishchenko, Vadim; Schöll, Eckehard

    2017-11-01

    Using the model of a FitzHugh-Nagumo system in the excitable regime, we investigate the influence of time-delayed feedback on noise-induced chimera states in a network with nonlocal coupling, i.e., coherence resonance chimeras. It is shown that time-delayed feedback allows for the control of the range of parameter values where these chimera states occur. Moreover, for the feedback delay close to the intrinsic period of the system, we find a novel regime which we call period-two coherence resonance chimera.

  14. Low-dose ionizing irradiation triggers a 53BP1 response to DNA double strand breaks in mouse spermatogonial stem cells.

    Science.gov (United States)

    Le, Wei; Qi, Lixin; Li, Jiaxuan; Wu, DengIong; Xu, Jun; Zhang, Jinfu

    2016-01-01

    The present study aims to examine the effect of low-dose ionizing irradiation on DNA double strand breaks (DSB) in mouse spermatogonial stem cells (SSCs) and reveal the underlying pathways for the DNA repair for DSB in SSCs. Eighteen one-month-old mice were divided into 6 groups and sacrificed separately at 45 minutes, 2 hours, 24 hours, 48 hours, and 72 hours after 0.1Gy X-ray irradiation (mice without receiving ionizing irradiation served as control). After perfusion fixation, testes were removed, sectioned, and followed by staining of γH2AX, 53BP1, Caspase 3, and promyelocytic leukemia zinc-finger (PLZF) for analysis among the different groups. The staining was observed by immunofluorescence visualized by confocal laser scanning. After low-dose irradiation, only 53BP1, but not Caspase3 or γH2AX was upregulated in PLZF positive SSCs within 45 minutes. The expression level of 53BP1 gradually decreased 24 hours after irradiation. Moreover, low-dose irradiation had no effect on the cell number and apoptotic status of SSCs. However other spermatogenic cells highly expressed γH2AX shortly after irradiation which was dramatically reduced following the events of DNA repair. It appears that low-dose ionizing irradiation may cause the DNA DSB of mouse spermatogenic cells. 53BP1, but not γH2AX, is involved in the DNA repair for DSB in SSCs. Our data indicates that 53BP1 plays an important role in the pathophysiological repair of DNA DSB in SSCs. This may open a new avenue to understanding the mechanisms of DNA repair of SSCs and male infertility.

  15. Proliferation studies of the endothelial and smooth muscle cells of the mouse mesentery after irradiation

    International Nuclear Information System (INIS)

    Hirst, D.G.; Denekamp, J.; Hobson, B.

    1980-01-01

    A continuous tritium labelling technique was employed to study the effects of external β-radiation on the proliferation of endothelial cells and smooth muscle cells in the mesenteric arterioles of mice. Calculations showed very long turnover times for the two cell populations in control animals (> 2 years for endothelium and > 3 years for smooth muscle). After single doses of 20 and 45 Gy, no significant increase in endothelial proliferation was seen except at 3 weeks. No significant increase in labelling was observed in smooth muscle up to 48 weeks after irradiation. These labelling data have been compared with the pattern of cell depletion of the irradiated endothelium. It was concluded that the depletion was much earlier than expected for a slowly proliferating tissue, if all the cells were cycling very slowly. Such an early depletion is, however, consistent with cell death resulting from a small proportion of the cells having a short cell cycle. The recovery of the endothelial cell numbers between 9 and 12 months was not accompanied by a rise in the fraction of labelled cells. It is suggested that repopulation may occur from outside the treated area. (author)

  16. Prenatal death and malformations after irradiation of mouse zygotes with neutrons or X-rays

    International Nuclear Information System (INIS)

    Pampfer, S.; Streffer, C.

    1988-01-01

    Female mice (strain: Heiligenberger Stamm) were irradiated with neutrons (7 MeV) or X-rays when embryos were at the early zygote stage; uterine contents were examined on gestation day 19 for prenatal mortality and malformed fetuses. For both radiation qualities, the dose-dependent survival curve fitted well to a simple exponential equation; the neutron relative biological efficiency (RBE) value was 2.3. The major fraction of deaths induced by exposure to neutrons or X-rays occurred before implantation. Aside from dead embryos, malformed fetuses were observed 19 days p.c. (postconception). The number of malformed fetuses increased with a linear-quadratic function of neutron or X-ray dose. Malformations were mainly gastroschisis, although omphaloceles and anencephalies were also observed. The neutron RBE value for the induction of malformations varied from 2.0 to 2.8 in the dose range tested. Except after 75-cGy neutrons, no significant increase in the proportion of stunted or skeletally malformed fetuses was noted. Our results indicated that the reaction of preimplantation embryos to irradiation could be more complex than the simple all-or-none response considered so far

  17. Focused microwave irradiation-assisted immunohistochemistry to study effects of ketamine on phospho-ERK expression in the mouse brain.

    Science.gov (United States)

    Fernandes, Alda; Li, Yu-Wen

    2017-09-01

    Ketamine produces rapid and long-lasting antidepressant effects in depressive patients. Preclinical studies demonstrate that ketamine stimulates AMPA receptor transmission and activates BDNF/TrkB-Akt/ERK-mTOR signaling cascades, leading to a sustained increase in synaptic protein synthesis and strengthening of synaptic plasticity, a potential mechanism underlying the antidepressant effects. The purpose of this study was to develop an immunohistochemistry (IHC) assay to map the distribution of extracellular signal-regulated kinase (ERK) phosphorylation in the mouse brain in response to systemic ketamine treatment. We established a focused microwave irradiation-assisted IHC assay to detect phosphorylated (phospho) proteins including phospho-ERK, phospho- cAMP-response- element-binding protein (CREB), phospho- glutamate receptor 1 (GluR1) and phospho- calcium/calmodulin-dependent protein kinase II (CaMKII) with greater sensitivity and reproducibility in comparison to conventional IHC methods. A single dose of ketamine produced a robust, dose- and time-dependent increase in phospho-ERK immunoreactive (phospho-ERK-ir) neurons in the medial prefrontal cortex (mPFC) and the central nucleus of the amygdala. Phospho-ERK-ir neurons in the mPFC were primarily located in the prelimbic and anterior cingulate subregions with the morphology resembling pyramidal neurons. An increase in phospho-ERK-ir was also observed in the brainstem dorsal raphe nucleus and locus coeruleus. The NMDA GluN2B subtype receptor antagonist Ro 25-6981 increased phospho-ERK expression in the brain in a similar pattern as ketamine. In summary, we have established a sensitive and reliable focused microwave irradiation-assisted IHC assay, and defined the activation pattern of ERK, in response to systemic ketamine and Ro 25-6981 treatment, in brain regions that are potentially responsible for mediating the antidepressant effects. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. Developmental abnormalities of the vitreous in mouse fetuses caused by simultaneous irradiation of x-rays and ultrasound

    Energy Technology Data Exchange (ETDEWEB)

    Shirai, S; Yuguchi, S; Majima, A [Nagoya City Univ. (Japan). Faculty of Medicine

    1980-10-01

    Eye abnormalities in mouse fetuses caused by irradiation of X-rays alone, or simultaneous irradiation of X-rays and ultrasound on day 7 of gestation were histologically studied on day 18 of gestation. Developmental abnormalities of the vitreous were examined in the present experiment, and the following results were obtained. 1. Developmental abnormalities of the vitreous were observed in 23 fetuses, and unilateral cases were 15 of 23 fetuses. In 31 eyes with these abnormalities, much more abundant mesenchymal tissue of components of primary vitreous was found in the retrolental vitreous cavity than in the normal eyes. 2. The above 31 eyes were also accompanied by a variety of ocular abnormalities such as microphthalmia, faulty closure of the fetal fissure, aplasia and hypoplasia of the optic nerve, goniodysgenesis, and corneolenticular adhesion. Complications observed to be associated with developmental abnormalities of the vitreous were lens abnormalities, retinal traction and fold, fibrovascular anastomosis between mesenchymal tissues of the chamber angle and vitreous cavity, retinal rosette, and anomalies of the optic nerve head. 3. The histological findings of 17 eyes corresponded to anterior persistent hyperplastic primary vitreous (PHPV) encountered clinically, those of 3 eyes to posterior PHPV, those of 6 eyes to mixed type of both anterior and posterior types, and those of 5 eyes to PHPV of the optic nerve head. In 3 bilateral cases, the type was different for either eye. 4. From these results, it was considered that the pathogenesis of PHPV of Reese and congenital retinal fold of Mann consists of the maldevelopment of the components of the primary vitreous, and that the type of defect depends on the portion involved and the degree depends on the time at which the maldevelopment occurs.

  19. Developmental abnormalities of the vitreous in mouse fetuses caused by simultaneous irradiation of x-rays and ultrasound

    International Nuclear Information System (INIS)

    Shirai, Shoichiro; Yuguchi, Shuji; Majima, Akio

    1980-01-01

    Eye abnormalities in mouse fetuses caused by irradiation of X-rays alone, or simultaneous irradiation of X-rays and ultrasound on day 7 of gestation were histologically studied on day 18 of gestation. Developmental abnormalities of the vitreous were examined in the present experiment, and the following results were obtained. 1. Developmental abnormalities of the vitreous were observed in 23 fetused, and unilateral cases were 15 of 23 fetuses. In 31 eyes with these abnormalities, much more abundant mesenchymal tissue of components of primary vitreous was found in the retrolental vitreous cavity than in the normal eyes. 2. The above 31 eyes were also accompanied by a variety of ocular abnormalities such as microphthalmia, faulty closure of the fetal fissure, aplasia and hypoplasia of the optic nerve, goniodysgenesis, and corneolenticular adhesion. Complications observed to be associated with developmental abnormalities of the vitreous were lens abnormalities, retinal traction and fold, fibrovascular anastomosis between mesenchymal tissues of the chamber angle and vitrious cavity, retinal rosette, and anomalies of the optic nerve head. 3. The histological findings of 17 eyes corresponded to anterior persistent hyperplastic primary vitreous (PHPV) encountered clinically, those of 3 eyes to posterior PHPV, those of 6 eyes to mixed type of both anterior and posterior types, and those of 5 eyes to PHPV of the optic nerve head. In 3 bilateral cases, the type was different for either eye. 4. From these results, it was considered that the pathogenesis of PHPV of Reese and congenital retinal fold of Mann consists of the maldevelopment of the components of the primary vitreous, and that the type of defect is depends on the portion involved and the degree depends on the time at which the maldevelopment occurs. (author)

  20. Biosynthesis of collagen in the lung of the mouse after X-irradiation

    International Nuclear Information System (INIS)

    Walklin, C.M.; Law, M.P.

    1986-01-01

    Increases in the activities of both prolyl-4-hydroxylase (P-4-Hase) and protein disulphide isomerase (PDI) were observed as early as 1 month after 5-9 Gy. Maximal increases were observed at 6-7 months after 9 Gy and persisted up to 15 months after exposure. Increases after 5 and 7.5 Gy were more gradual but by 1 year after irradiation they had reached levels similar to those after 9 Gy. Collagen types were analysed at 2, 7.5 and 15 months. Results are shown for 7.5 and 15 months after 9 Gy. Although the total collagen content was increased, the ratio of collagen type I to III was normal. (UK)

  1. The development and characterization of two types of chronic responses in irradiated mouse colon

    International Nuclear Information System (INIS)

    Followill, D.S.

    1991-01-01

    The hypothesis to be tested is that there are two distinct types of chronic responses in irradiated normal tissues, each resulting from damage to different cell populations in the tissue. The first is a sequela of chronic epithelial depletion in which the tissue's integrity cannot be maintained. The other response is due to cell loss in the connective tissue and/or vascular stroma, i.e. a 'primary' chronic response. The purpose of this study was to test the hypothesis in the murine colon by first, establishing a model of each chronic response and then, by determining whether the responses differed in timing of expression, histology, and expression of specific collagen types. The model of late damage used was colonic obstructions/strictures induced by a single dose of 27 Gy ('consequential' response) and two equal doses of 14.75 Gy (t = 10 days) ('primary' response). 'Consequential' lesions appeared as early as 5 weeks after 27 Gy and were characterized by a deep mucosal ulceration and a thickened fibrotic serosa containing excessive accumulations of collagen types I and III. Both types were commingled in the scar at the base of the ulcer. Fibroblasts were synthesizing pro-collagen types I and III mRNA 10 weeks prior to measurable increases in collagen. A significant decrease in the ratio of collagen types I:III was associated with the 'consequential' response at 4-5 months post-irradiation. The 'primary' response, on the other hand, did not appear until 40 weeks after the split dose even though the total dose delivered was approximately the same as that for the 'consequential' response. The 'primary' response was characterized with an intact mucosa and a thickened fibrotic submucosa which contained excessive amounts of only collagen type I. An increased number of fibroblasts were synthesizing pro-collagen type I mRNA nearly 25 weeks before collage type I levels were increased

  2. Scanning electron microscopy of mouse intestinal mucosa after cobalt 60 and D-T neutron irradiation

    International Nuclear Information System (INIS)

    Hamlet, R.; Carr, K.R.; Toner, P.G.; Nias, A.H.W.

    1976-01-01

    The stem-cell population of the intestinal crypt is an important model system in experimental radiobiology. Standardized techniques have been developed to allow quantitation of the response of crypt cells to radiation injury following doses of 0 to 2 krad of D-T neutrons or 60 Co γ rays. These techniques rely on the identification of regenerating crypt cells three-and-a-half days after irradiation. The results were expressed as the number of regenerating crypts per circumference of small intestine, as determined by conventional histological examination; the more profound the injury, the smaller the the crypt count. The practical relevance of crypt-counting techniques to clinical radiotherapy is limited by their relative insensitivity; the dose levels commonly used in fractionated radiotherapy produced no detectable response. Scanning electron microscopy of the mucosal surface provided a more sensitive measure of radiation injury. The earliest detectable changes occurred at the level of 300 rad of γ radiation, well below the threshold of the crypt-counting technique. At around 1,000 rad, where the first drop in crypt counts occurred, there were well-marked morphological changes which became more severe with increasing dose levels. Some differences have been observed between the morphological effects of γ and neutron irradiation at points of radiobiological equivalence in terms of crypt counts (using RBE value of about 2). The changes observed may reflect more than the disruption of epithelial cell kinetics. Mucosal morphology is the total expression of many different biological parameters of which the regenerative ability of the crypt cells is only one. The surface microanatomy of the gut may be the most sensitive indicator of radiation injury which is conveniently available for study. (author)

  3. Scanning electron microscopy of mouse intestinal mucosa after cobalt 60 and D-T neutron irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Hamlet, R [Belvidere Hospital, Glasgow (UK). Institute of Radiotherapeutics and Oncology; Carr, K R; Toner, P G; Nias, A H.W.

    1976-07-01

    The stem-cell population of the intestinal crypt is an important model system in experimental radiobiology. Standardized techniques have been developed to allow quantitation of the response of crypt cells to radiation injury following doses of 0 to 2 krad of D-T neutrons or /sup 60/Co ..gamma.. rays. These techniques rely on the identification of regenerating crypt cells three-and-a-half days after irradiation. The results were expressed as the number of regenerating crypts per circumference of small intestine, as determined by conventional histological examination; the more profound the injury, the smaller the the crypt count. The practical relevance of crypt-counting techniques to clinical radiotherapy is limited by their relative insensitivity; the dose levels commonly used in fractionated radiotherapy produced no detectable response. Scanning electron microscopy of the mucosal surface provided a more sensitive measure of radiation injury. The earliest detectable changes occurred at the level of 300 rad of ..gamma.. radiation, well below the threshold of the crypt-counting technique. At around 1,000 rad, where the first drop in crypt counts occurred, there were well-marked morphological changes which became more severe with increasing dose levels. Some differences have been observed between the morphological effects of ..gamma.. and neutron irradiation at points of radiobiological equivalence in terms ofCrypt counts (using RBE value of about 2). The changes observed may reflect more than the disruption of epithelial cell kinetics. Mucosal morphology is the total expression of many different biological parameters of which the regenerative ability of the crypt cells is only one. The surface microanatomy of the gut may be the most sensitive indicator of radiation injury which is conveniently available for study.

  4. Reduction in sperm count and increase in abnormal sperm in the mouse following x-irradiation or injection of 22Na

    International Nuclear Information System (INIS)

    Harrison, A.; Moore, P.C.

    1980-01-01

    The accumulated reduction in sperm count and increase in the number of aberrant sperm in the mouse were used to compare acute X-irradiation with protracted radiation from an injection of 22 Na. The effects per unit of absorbed dose of acute and protracted radiation were similar on sperm count, but in respect of numbers of abnormal sperm the 22 Na induced a significantly greater maximum than X-rays. (author)

  5. Effect of radiation dose rate and cyclophosphamide on pulmonary toxicity after total body irradiation in a mouse model

    International Nuclear Information System (INIS)

    Safwat, Akmal; Nielsen, Ole S.; El-Badawy, Samy; Overgaard, Jens

    1996-01-01

    Purpose: Interstitial pneumonitis (IP) is still a major complication after total body irradiation (TBI) and bone marrow transplantation (BMT). It is difficult to determine the exact role of radiation in this multifactorial complication, especially because most of the experimental work on lung damage was done using localized lung irradiation and not TBI. We have thus tested the effect of radiation dose rate and combining cyclophosphamide (CTX) with single fraction TBI on lung damage in a mouse model for BMT. Methods and Materials: TBI was given as a single fraction at a high dose rate (HDR, 0.71 Gy/min) or a low dose rate (LDR, 0.08 Gy/min). CTX (250 mg/kg) was given 24 h before TBI. Bone marrow transplantation (BMT) was performed 4-6 h after the last treatment. Lung damage was assessed using ventilation rate (VR) and lethality between 28 and 180 days (LD (50(28))-180 ). Results: The LD 50 for lung damage, ± standard error (SE), increased from 12.0 (± 0.2) Gy using single fraction HDR to 15.8 (± 0.6) Gy using LDR. Adding CTX shifted the dose-response curves towards lower doses. The LD 50 values for the combined treatment were 5.3 (± 0.2) and 3.5 (± 0.2) Gy for HDR and LDR, respectively. This indicates that the combined effect of CTX and LDR was more toxic than that of combined CTX and HDR. Lung damage evaluated by VR demonstrated two waves of VR increase. The first wave of VR increase occurred after 6 weeks using TBI only and after 3 weeks in the combined CTX-TBI treatment, irrespective of total dose or dose rate. The second wave of VR elevation resembled the IP that follows localized thoracic irradiation in its time of occurrence. Conclusions: Lung damage following TBI could be spared using LDR. However, CTX markedly enhances TBI-induced lung damage. The combination of CTX and LDR is more toxic to the lungs than combining CTX and HDR

  6. WE-EF-BRA-10: Prophylactic Cranial Irradiation Reduces the Incidence of Brain Metastasis in a Mouse Model of Metastatic Breast Cancerr

    Energy Technology Data Exchange (ETDEWEB)

    Smith, D; Debeb, B; Larson, R; Diagaradjane, P; Woodward, W [MD Anderson Cancer Center, Houston, TX (United States)

    2015-06-15

    Purpose: Prophylactic cranial irradiation (PCI) is a clinical technique used to reduce the incidence of brain metastasis and improve overall survival in select patients with acute lymphoblastic leukemia and small-cell lung cancer. We examined whether PCI could benefit breast cancer patients at high risk of developing brain metastases. Methods: We utilized our mouse model in which 500k green fluorescent protein (GFP)-labeled breast cancer cells injected into the tail vein of SCID/Beige mice resulted in brain metastases in approximately two-thirds of untreated mice. To test the efficacy of PCI, one set of mice was irradiated five days after cell injection with a single fraction of 4-Gy (two 2-Gy opposing fields) whole-brain irradiation on the XRAD 225Cx small-animal irradiator. Four controls were included: a non-irradiated group, a group irradiated two days prior to cell injection, and two groups irradiated 3 or 6 weeks after cell injection. Mice were sacrificed four and eight weeks post-injection and were evaluated for the presence of brain metastases on a fluorescent stereomicroscope. Results: The incidence of brain metastasis in the non-irradiated group was 77% and 90% at four and eight weeks, respectively. The PCI group had a significantly lower incidence, 20% and 30%, whereas the other three control groups had incidence rates similar to the non-treated control (70% to 100%). Further, the number of metastases and the metastatic burden were also significantly lower in the PCI group compared to all other groups. Conclusion: The timing of irradiation to treat subclinical disease is critical, as a small dose of whole-brain irradiation given five days after cell injection abrogated tumor burden by greater than 90%, but had no effect when administered twenty-one days after cell injection. PCI is likely to benefit breast cancer patients at high risk of developing brain metastases and should be strongly considered in the clinic.

  7. Enzymatic method for the sensitive demonstration of postnatal effects caused by prenatal X-irradiation in mouse brain

    International Nuclear Information System (INIS)

    Weber, L.W.D.; Schmahl, W.G.; Kriegel, H.

    1982-01-01

    We have investigated the activities (per gram of wet tissue) of mouse brain acetylcholinesterase and Na, K-ATPase, with respect to the effects brought about by a prenatal X-ray dose. Pregnant NMRI mice received an X-ray dose of 0.24, 0.49, 0.95 or 1.9 Gy each on the 12th day of gestation. Investigations on the offspring were performed on the day of birth and the postnatal days 2, 5, 8, 12, 16, 23, 34, 48 and 64, respectively. The brain weights were reduced by the X-ray treatment dose - dependently and without recovery. This was well discernible after 0.24 Gy and reached about 40% reduction after 1.9 Gy. There were significant differences between irradiated and control enzyme activities on most of the days examined. On the 48th postnatal day both enzymes' activities were thoroughly elevated after 0.24 and 0.49 Gy. This could be reproduced in another test series with 0.49 Gy, but vanished when enzyme activities were related to the brain protein contents. As a more reliable parameter of the developmental age brain weights were compared to the corresponding enzyme activities. (orig./MG)

  8. Biochemical transformation of deoxythymidine kinase-deficient mouse cells with uv-irradiated equine herpesvirus type 1

    International Nuclear Information System (INIS)

    Allen, G.P.; McGowan, J.J.; Gentry, G.A.; Randall, C.C.

    1978-01-01

    A line of 3T3 mouse cells lacking deoxythymidine kinase (dTK - ) was stably transformed to the dTK + phenotype after exposure to uv-irradiated equine herpesvirus type 1 (EHV-1). Biochemical transformants were isolated in a system selective for the dTK + phenotype (Eagle minimal essential medium containing 10 -4 M hypoxanthine, 6 x 10 -7 M aminopterin, and 2 x 10 -5 M deoxythymidine). Transformation was accompanied by the acquisition of a dTK activity with immunological, electrophoretic, and biochemical characteristics identical to those of the dTK induced by EHV-1 during productive infection. The transformed cells have been maintained in selective culture medium for more than 50 passages and have retained the capacity to express EHV-1-specific antigens. Spontaneous release of infectious virus has not been detected in the transformed lines, and the cells were not oncogenic for athymic nude mice. In contrast to normal dTK + 3T3 cells, EHV-1 transformants were unable to grow in the presence of arabinosylthymine, a drug selectively phosphorylated by herpesvirus-coded dTK's. These results indicate that a portion of the EHV-1 genome is able to persist in the transformed cells for many generations and be expressed as an enzymatically active viral gene product

  9. Studies on induction of apoptosis in mouse Peyer's patches by whole body X-irradiation and its mechanisms

    International Nuclear Information System (INIS)

    Liu Jiamei; Chen Dong; Chen Aijun; Liu Shuzheng

    2001-01-01

    Objective: To study the effect of apoptosis-related genes in mouse Peyer's patches and its molecular mechanism after whole body irradiation (WBI) with different doses of X-rays. Methods: Light microscopy and transmission electron microscopy were used to observe the morphology and structure of Peyer's patches and flow cytometry (FCM) was used to detect the changes of Bcl-x L and Fas-L proteins. Results: The apoptosis in Peyer's patches was increased after 2 Gy X-rays and decreased after 75 mGy X-rays. The expression of Bcl-x L protein was decreased and the expression of Fas-L protein was increased in Peyer's patches after WBI with 2 Gy X-rays, whereas the former increased and the latter decreased after WBI with 75 mGy. Conclusion: Apoptosis-related genes such as Bcl-x L , Fas-L might play an important role in regulation of radiation-induced apoptosis in Peyer's patches

  10. Effect of time between x-irradiation and chemotherapy on the growth of three solid mouse tumors. V. Bleomycin

    International Nuclear Information System (INIS)

    Twentyman, P.R.; Kallman, R.F.; Brown, J.M.

    1979-01-01

    Experiments have been carried out to determine the effect of different time intervals between the administration of x-radiation (1200 rad) and bleomycin (20 mg/kg) on the growth delay produced in three mouse tumors. The tumors used were the EMT6 tumor in BALB/c mice and the KHT and RIF-1 sarcomas in C3H mice. All tumors were grown intramuscularly in the gastrocnemius muscle and treatment was carried out at a mean tumor weight of 450 mg. Time to reach 2X (for KHT) or 4X (for EMT6 and RIF-1) treatment volume was used as the endpoint of response. The drug was administered by the intraperitoneal route either 24, 6, or 2 hr before radiation, immediately before the start of radiation, or 3, 6, or 24 hr after radiation. All irradiations were carried out in unanesthetized mice. For a single administration at this dose level, bleomycin alone did not produce a significant growth delay in any of the tumors. In the RIF-1 tumor, growth delays following combination treatments were equal to the addition of the single agent growth delays. In two experiments with EMT6, contrary results were obtained, one producing longer delays following combination treatments than predicted and the other producing shorter delays. This is apparently due to the variability in the growth delay after treatment with radiation alone for this tumor. For the KHT tumor, only small differences from the addition of single agent delays were seen

  11. Pathologic characteristics of gut-associated lymphoid tissues and lymphocyte apoptosis in mouse intestine after neutron-and γ-irradiation

    International Nuclear Information System (INIS)

    Fu Kaifei; Peng Ruiyun; Gao Yabing; Wang Dewen; Chen Haoyu; Wu Xiaohong; Yang Yi; Hu Wenhua; Ma Junjie

    2004-01-01

    Objective: To compare the pathologic characteristics of gut-associated lymphoid tissues and lymphocyte apoptosis in neutron-irradiated mouse small intestines with those in γ-irradiated ones. Methods: Altogether 350 BALB/c mice were irradiated with different doses of neutrons or γ-rays, and were sacrificed on 6 h,12 h,125 d, 7 d, 14 d, 21 d and 28 d after irradiation and their total intestines were removed. Then the pathologic changes and death mode of lymphocytes in gut-associated lymphoid tissues were studied comparatively with light microscopy, electron microscopy and in situ terminal labeling method. Results: The basic pathologic changes of gut-associated lymphoid tissues after neutron irradiation included degeneration, apoptosis and necrosis of lymphocytes. The number of lymphocytes also decreased. There was no obvious regeneration after 4.0 and 5.5 Gy neutron irradiation, while after 2.5 Gy regeneration and recovery appeared, which were, there fore, dose-dependent. In the 2.5 Gy neutron group, the numbers of lymphocytes of intramucosal and submucous lymphoid tissues decreased, and karyopyknosis and a great quantity of nuclear fragments could also be observed at 6 h-3 d after irradiation. However, on the 3rd day regeneration of crypt epithelial cells appeared. On the 5th day hyperplasia of submucous lymphocytic tissues appeared, but recovery to normal level was not achieved till 14 d after irradiation. The basic pathologic changes after γ-irradiation were similar to that of neutron irradiation. Regeneration and recovery appeared in the 5.5 Gy group while no obvious regeneration in the 12.0 Gy group. The results of in situ terminal labeling indicated that at 6 h after irradiation the number of apoptotic cells in gut-associated lymphoid tissues of each group increased obviously, while in 4.0 Gy neutron group and 12.0 Gy γ-ray group it was more abundant. Conclusion: Both 2.5-5.5 Gy neutron and 5.5-12.0 Gy γ-ray irradiation can induce obvious injuries in gut

  12. Differences in susceptibility among mouse strains to infection with Plasmodium berghei (ANKA clone) sporozoites and its relationship to protection by gamma-irradiated sporozoites

    International Nuclear Information System (INIS)

    Jaffe, R.I.; Lowell, G.H.; Gordon, D.M.

    1990-01-01

    Three inbred mouse strains, C57BL/6 (H-2b), A/J (H-2a), and BALB/c (H-2d), and 1 outbred strain, CD-1, demonstrated differences in susceptibility to iv challenge with the ANKA clone of Plasmodium berghei. Mice were challenged with 100, 1,000, or 10,000 sporozoites, then evaluated daily beginning on day 4 for patency. CD-1 mice were further evaluated at challenge doses of 12,500, 25,000, and 50,000 sporozoites. C57BL/6 mice were the easiest to infect, with 90% becoming infected with 100 sporozoites. The outbred strain CD-1 was the most difficult to infect, requiring a challenge dose of 25,000 sporozoites/mouse in order to achieve a 100% infection rate. Mouse strains also demonstrated differences in their ability to be protected by intravenous immunization with gamma-irradiated sporozoites. A/J mice needed a minimum of 3 doses of irradiated sporozoites for protection against a challenge with 10,000 sporozoites. In contrast, BALB/c mice immunized with a single dose of 1,000 irradiated sporozoites are protected against a 10,000 sporozoite challenge. These data suggest that both infectivity and protection are genetically restricted and that susceptibility to infection may be inversely related to protection

  13. Allogeneic radiation chimeras respond to TNP-modified donor and host targets

    International Nuclear Information System (INIS)

    Lattime, E.C.; Gershon, H.E.; Stutman, O.

    1980-01-01

    Tolerance to major histocompatibility antigens as well as the ability to mount a cytotoxic response to hapten-modified cells of bone marrow donor and host origin was studied in allogeneic radiation chimeras. Lethally irradiated (C57BL/6 x DBA/2)F1 hosts reconstituted with anti-Thy 1.2 + C-treated bone marrow from (C57BL/6 x CBA)F1 mice showed tolerance to the MHC antigens of the three parental strains as measured by MLC and CML assay. The chimeras responded normally to unrelated allogeneic cells. Chimeric animals generated a cytotoxic response to hapten-modified cells of both donor (CBA) and host (DBA/2) haplotypes, as well as to C57BL/6, demonstrating that tolerance to the hapten-presenting host haplotype is sufficient to allow a cytotoxic antihapten response, and that processing through a semiallogeneic host environment does not affect the ability to generate a response to hapten in conjunction with self-determinants. Chimeras failed to mount a cytotoxic response to hapten presented on nontolerated allogeneic spleen cells

  14. A Comparison of Molecular and Histopathological Changes in Mouse Intestinal Tissue Following Whole-Body Proton- or Gamma-Irradiation

    Science.gov (United States)

    Purgason, Ashley; Mangala, Lingegowda; Zhang, Ye; Hamilton, Stanley; Wu, Honglu

    2010-01-01

    There are many consequences following exposure to the space radiation environment which can adversely affect the health of a crew member. Acute radiation syndrome (ARS) involving nausea and vomiting, damage to radio-sensitive tissue such as the blood forming organs and gastrointestinal tract, and cancer are some of these negative effects. The space radiation environment is ample with protons and contains gamma rays as well. Little knowledge exists to this point, however, regarding the effects of protons on mammalian systems; conversely several studies have been performed observing the effects of gamma rays on different animal models. For the research presented here, we wish to compare our previous work looking at whole-body exposure to protons using a mouse model to our studies of mice experiencing whole-body exposure to gamma rays as part of the radio-adaptive response. Radio-adaptation is a well-documented phenomenon in which cells exposed to a priming low dose of radiation prior to a higher dose display a reduction in endpoints like chromosomal aberrations, cell death, micronucleus formation, and more when compared to their counterparts receiving high dose-irradiation only. Our group has recently completed a radio-adaptive experiment with C57BL/6 mice. For both this study and the preceding proton research, the gastrointestinal tract of each animal was dissected four hours post-irradiation and the isolated small intestinal tissue was fixed in formalin for histopathological examination or snap-frozen in liquid nitrogen for RNA isolation. Histopathologic observation of the tissue using standard H&E staining methods to screen for morphologic changes showed an increase in apoptotic lesions for even the lowest doses of 0.1 Gy of protons and 0.05 Gy of gamma rays, and the percentage of apoptotic cells increased with increasing dose. A smaller percentage of crypts showed 3 or more apoptotic lesions in animals that received 6 Gy of gamma-irradiation compared to mice

  15. Lack of correlation between villus and crypt damage in irradiated mouse intestine

    International Nuclear Information System (INIS)

    Carr, K.E.; Hamlet, R.; Nias, A.H.W.; Watt, C.

    1979-01-01

    It has been observed that scanning electron microscopy is a more sensitive indicator of mucosal damage at low radiation dose levels than conventional quantitative crypt counting techniques. Three different fractionation schedules were subjected to investigation by both of these methods to try and elucidate some features of irradiation damage to the whole of the intestinal mucosa, at dose levels commonly used in clinical practice. Despite variations in the qualitative observations, there was a marked difference in two of the schedules between damage expressed as crypt counts and that described by the qualitative techniques. In the first case high crypt numbers were associated with severe mucosal damage, whereas the second schedule produced a reduced crypt count in association with low damage to the surface mucosa. A third schedule produced results in which there was a general agreement between low crypt numbers and considerable surface mucosal damage. However, observations were made of mucosal formations not previously seen on damaged mucosa; surfaces. These resembled the appearance normally associated with the gut of patients suffering from coeliac disease. Variations in the qualitative observations were seen in the schedules so that their interpretation in terms of perturbation of cellular kinetics is difficult. (author)

  16. Dysplasia of the temporo-maxillary joint of mouse embryos due to x-ray irradiation

    International Nuclear Information System (INIS)

    Shibata, Shigeo

    1974-01-01

    On the 9-13 pregnant days of ddN mice 200-300 R of X-ray was daily irradiated, and observations were made on the formation of micro-mandible and changes in the temporo-maxillary joint in the embryos on the 18th pregnant day using skeletal and H-E stain specimens. Gross observation revealed the emergence of observable micro-mandible in groups exposed to 200 R on the 10th and 11th pregnant days and in groups exposed to 300 R on the 11th and 12th pregnant days. By skeletal specimens also, micro-mandible was observed in groups exposed on and after the 10th pregnant day, and anomaly of the malar arch was frequently associated with anomaly of the mandibular branches and growth inhibition of the anterior region of the mandible. Histologically, there were observed embryos totally lacking the temporo-maxillary joint composing elements, resulting in fusion with the temporal bone, or embryos lacking the elements partially or complicated by anomaly of cartilagious tissue of the mandibular head. (Mukohata, S.)

  17. Dominance and persistence of donor marrow in long-lived allogeneic radiation chimeras obtained with unmanipulated bone marrow

    International Nuclear Information System (INIS)

    Pierpaoli, W.; Maestroni, G.J.M.

    1983-01-01

    Allogeneic, H-2-incompatible irradiation chimeras (H-2sup(d) → H-2sup(b)) constructed with normal, unmanipulated bone marrow and with marrow-derived factors live long and do not manifest a GvH disease. Their response to primary immunization is deficient but their alloreactivity is normal. This chimeric allotolerance cannot be passively transferred from chimeric donors to normal irradiated recipients. Passive transfer of both donor- or recipient-type immuno-competent T-cells into the chimeric mice does not lead to syngeneic reconstitution, rejection of the engrafted marrow or GvH disease, and the mice maintain permanently their chimerism. This new model demonstrates that chimerism is not eradicable in long-lived chimeras reconstituted with unmanipulated bone marrow, and that the bone marrow itself plays a dominant role in maintenance of chimerism. (Auth.)

  18. Chimera states in a population of identical oscillators under planar ...

    Indian Academy of Sciences (India)

    finding, observed in both a collection of van der Pol oscillators and chaotic Rössler oscillators, fur- ther simplifies the existence criterion for chimeras, thereby broadens the range of their applicability to real-world situations. Keywords. Synchronization; chimera; Rössler system; van der Pol oscillator. PACS Nos 05.45.

  19. Assessing reprogramming by chimera formation and tetraploid complementation.

    Science.gov (United States)

    Li, Xin; Xia, Bao-long; Li, Wei; Zhou, Qi

    2015-01-01

    Pluripotent stem cells can be evaluated by pluripotent markers expression, embryoid body aggregation, teratoma formation, chimera contribution and even more, tetraploid complementation. Whether iPS cells in general are functionally equivalent to normal ESCs is difficult to establish. Here, we present the detailed procedure for chimera formation and tetraploid complementation, the most stringent criterion, to assessing pluripotency.

  20. Effects of ACNU and cranial irradiation on the mouse immune system

    Energy Technology Data Exchange (ETDEWEB)

    Yamanaka, Ryuya; Tanaka, Ryuichi; Yoshida, Seiichi; Mori, Hiroshi; Takeda, Norio; Satoh, Mitsuya [Niigata Univ. (Japan). Brain Research Inst.

    1993-02-01

    The effects of 1-(4-amino-2-methyl-5-pyrimidinyl)-methyl- 3-(2-chloroethyl)-3-nitrosourea (ACNU) and cranial irradiation on the immune system were studied in three groups of 90 mice: Group A, intraperitoneal injection of ACNU (30 mg/kg); Group B, single exposure of 10 Gy to the head; and Group C, intraperitoneal injection of ACNU (30 mg/kg) and single exposure of 10 Gy to the head. Peripheral white blood cell counts, spleen cell subsets, natural killer (NK) cell activity, lymphocyte blastogenesis, and production of interferon (IFN)-[gamma] were analyzed once a week for 6 weeks after treatment. In Group A, NK cell activity decreased between weeks 4-5, concanavalin A blastogenesis decreased during weeks 1-5, and the levels of L3T4 (CD4) and Lyt2 cells (CD8) and IFN-[gamma] production decreased during weeks 2-5. However, all tested parameters returned to the normal range at 6 weeks. In Group B, all parameters except for the L3T4 cell level and the IFN-[gamma] production decreased during week 1, and returned to the normal range thereafter. The concentration of L3T4 cells decreased during week 2 and between weeks 5-6. The IFN-[gamma] production increased during week 1, decreased during week 2, and returned to the normal range thereafter. In Group C, the suppressive effects were severe and continued for a longer period than in either Group A or B. Concanavalin A blastogenesis, L3T4 cell concentration, and IFN-[gamma] production were still suppressed after 6 weeks. Therefore, intensive radiochemotherapy for brain tumor may suppress the immunological function. (author).

  1. Analysis of structural and numerical chromosomal aberrations at the first and second mitosis after X irradiation of two-cell mouse embryos

    International Nuclear Information System (INIS)

    Weissenborn, U.; Streffer, C.

    1989-01-01

    Two-cell mouse embryos were X-irradiated in the late G2 phase in vivo. The first and second postradiation mitoses were analyzed for chromosomal anomalies. The majority of structural aberrations visible at the first mitosis after irradiation were chromatid breaks and chromatid gaps; only a few interchanges and dicentrics were observed. The aberration frequency resulted in a dose-effect relationship which was well described by a linear model. At the second mitosis 29% of the structural aberrations of the first mitosis were counted; the aberration quality changed only slightly. It is discussed whether these aberrations are to be considered new, derived, or unchanged transmitted aberrations. Contrary to the results obtained after irradiation of one-cell embryos, little chromosome loss was induced by radiation in two-cell embryos

  2. Chimera patterns in the Kuramoto–Battogtokh model

    International Nuclear Information System (INIS)

    Smirnov, Lev; Osipov, Grigory; Pikovsky, Arkady

    2017-01-01

    Kuramoto and Battogtokh (2002 Nonlinear Phenom. Complex Syst . 5 380) discovered chimera states represented by stable coexisting synchrony and asynchrony domains in a lattice of coupled oscillators. After a reformulation in terms of a local order parameter, the problem can be reduced to partial differential equations. We find uniformly rotating, spatially periodic chimera patterns as solutions of a reversible ordinary differential equation, and demonstrate a plethora of such states. In the limit of neutral coupling they reduce to analytical solutions in the form of one- and two-point chimera patterns as well as localized chimera solitons. Patterns at weakly attracting coupling are characterized by virtue of a perturbative approach. Stability analysis reveals that only the simplest chimeras with one synchronous region are stable. (letter)

  3. Implementing real-time robotic systems using CHIMERA II

    Science.gov (United States)

    Stewart, David B.; Schmitz, Donald E.; Khosla, Pradeep K.

    1990-01-01

    A description is given of the CHIMERA II programming environment and operating system, which was developed for implementing real-time robotic systems. Sensor-based robotic systems contain both general- and special-purpose hardware, and thus the development of applications tends to be a time-consuming task. The CHIMERA II environment is designed to reduce the development time by providing a convenient software interface between the hardware and the user. CHIMERA II supports flexible hardware configurations which are based on one or more VME-backplanes. All communication across multiple processors is transparent to the user through an extensive set of interprocessor communication primitives. CHIMERA II also provides a high-performance real-time kernel which supports both deadline and highest-priority-first scheduling. The flexibility of CHIMERA II allows hierarchical models for robot control, such as NASREM, to be implemented with minimal programming time and effort.

  4. Chimera patterns in the Kuramoto-Battogtokh model

    Science.gov (United States)

    Smirnov, Lev; Osipov, Grigory; Pikovsky, Arkady

    2017-02-01

    Kuramoto and Battogtokh (2002 Nonlinear Phenom. Complex Syst. 5 380) discovered chimera states represented by stable coexisting synchrony and asynchrony domains in a lattice of coupled oscillators. After a reformulation in terms of a local order parameter, the problem can be reduced to partial differential equations. We find uniformly rotating, spatially periodic chimera patterns as solutions of a reversible ordinary differential equation, and demonstrate a plethora of such states. In the limit of neutral coupling they reduce to analytical solutions in the form of one- and two-point chimera patterns as well as localized chimera solitons. Patterns at weakly attracting coupling are characterized by virtue of a perturbative approach. Stability analysis reveals that only the simplest chimeras with one synchronous region are stable.

  5. Metaphysical and ethical perspectives on creating animal-human chimeras.

    Science.gov (United States)

    Eberl, Jason T; Ballard, Rebecca A

    2009-10-01

    This paper addresses several questions related to the nature, production, and use of animal-human (a-h) chimeras. At the heart of the issue is whether certain types of a-h chimeras should be brought into existence, and, if they are, how we should treat such creatures. In our current research environment, we recognize a dichotomy between research involving nonhuman animal subjects and research involving human subjects, and the classification of a research protocol into one of these categories will trigger different ethical standards as to the moral permissibility of the research in question. Are a-h chimeras entitled to the more restrictive and protective ethical standards applied to human research subjects? We elucidate an Aristotelian-Thomistic metaphysical framework in which to argue how such chimeras ought to be defined ontologically. We then examine when the creation of, and experimentation upon, certain types of a-h chimeras may be morally permissible.

  6. Solvable model of spiral wave chimeras.

    Science.gov (United States)

    Martens, Erik A; Laing, Carlo R; Strogatz, Steven H

    2010-01-29

    Spiral waves are ubiquitous in two-dimensional systems of chemical or biological oscillators coupled locally by diffusion. At the center of such spirals is a phase singularity, a topological defect where the oscillator amplitude drops to zero. But if the coupling is nonlocal, a new kind of spiral can occur, with a circular core consisting of desynchronized oscillators running at full amplitude. Here, we provide the first analytical description of such a spiral wave chimera and use perturbation theory to calculate its rotation speed and the size of its incoherent core.

  7. A 3-D chimera grid embedding technique

    Science.gov (United States)

    Benek, J. A.; Buning, P. G.; Steger, J. L.

    1985-01-01

    A three-dimensional (3-D) chimera grid-embedding technique is described. The technique simplifies the construction of computational grids about complex geometries. The method subdivides the physical domain into regions which can accommodate easily generated grids. Communication among the grids is accomplished by interpolation of the dependent variables at grid boundaries. The procedures for constructing the composite mesh and the associated data structures are described. The method is demonstrated by solution of the Euler equations for the transonic flow about a wing/body, wing/body/tail, and a configuration of three ellipsoidal bodies.

  8. Solvable Model of Spiral Wave Chimeras

    DEFF Research Database (Denmark)

    Martens, Erik Andreas; Laing, Carlo R.; Strogatz, Steven H.

    2010-01-01

    Spiral waves are ubiquitous in two-dimensional systems of chemical or biological oscillators coupled locally by diffusion. At the center of such spirals is a phase singularity, a topological defect where the oscillator amplitude drops to zero. But if the coupling is nonlocal, a new kind of spiral...... can occur, with a circular core consisting of desynchronized oscillators running at full amplitude. Here, we provide the first analytical description of such a spiral wave chimera and use perturbation theory to calculate its rotation speed and the size of its incoherent core....

  9. Induction of a Radio-Adaptive Response by Low-dose Gamma Irradiation in Mouse Cardiomyocytes

    Science.gov (United States)

    Westby, Christian M.; Seawright, John W.; Wu, Honglu

    2011-01-01

    One of the most significant occupational hazards to an astronaut is the frequent exposure to radiation. Commonly associated with increased risk for cancer related morbidity and mortality, radiation is also known to increase the risk for cardiovascular related disorders including: pericarditis, hypertension, and heart failure. It is believed that these radiation-induced disorders are a result of abnormal tissue remodeling. It is unknown whether radiation exposure promotes remodeling through fibrotic changes alone or in combination with programmed cell death. Furthermore, it is not known whether it is possible to mitigate the hazardous effects of radiation exposure. As such, we assessed the expression and mechanisms of radiation-induced tissue remodeling and potential radio-adaptive responses of p53-mediated apoptosis and fibrosis pathways along with markers for oxidative stress and inflammation in mice myocardium. 7 week old, male, C57Bl/6 mice were exposed to 6Gy (H) or 5cGy followed 24hr later with 6Gy (LH) 137Cs gamma radiation. Mice were sacrificed and their hearts extirpated 4, 24, or 72hr after final irradiation. Real Time - Polymerase Chain Reaction was used to evaluate target genes. Apoptotic genes Bad and Bax, pro-cell survival genes Bcl2 and Bcl2l2, fibrosis gene Vegfa, and oxidative stress genes Sod2 and GPx4 showed a reduced fold regulation change (Bad,-6.18; Bax,-6.94; Bcl2,-5.09; Bcl2l2,-4.03; Vegfa, -11.84; Sod2,-5.97; GPx4*,-28.72; * = Bonferroni adjusted p-value present compared to 24hr control. These data suggest a general reduction in genetic expression 4hrs after a high dose of gamma radiation. However, pre-exposure to 5cGy gamma radiation appears to facilitate a radio-adaptive response that mitigates the reduction in genetic expression associated with single high-dose gamma radiation exposure. This radio-adaptive response may serve as a potential countermeasure to radiation-induced myocardial remodeling and preserve the cardiovascular health of

  10. 77 FR 65602 - Chimera Energy Corporation; Order of Suspension of Trading

    Science.gov (United States)

    2012-10-29

    ... SECURITIES AND EXCHANGE COMMISSION [File No. 500-1] Chimera Energy Corporation; Order of... lack of current and accurate information concerning the securities of Chimera Energy Corporation (``Chimera'') because of questions regarding the accuracy of statements by Chimera in press releases to...

  11. Fatty acids activate a chimera of the clofibric acid-activated receptor and the glucocorticoid receptor.

    Science.gov (United States)

    Göttlicher, M; Widmark, E; Li, Q; Gustafsson, J A

    1992-01-01

    Peroxisome proliferators such as clofibric acid, nafenopin, and WY-14,643 have been shown to activate PPAR (peroxisome proliferator-activated receptor), a member of the steroid nuclear receptor superfamily. We have cloned the cDNA from the rat that is homologous to that from the mouse [Issemann, I. & Green, S. (1990) Nature (London) 347, 645-650], which encodes a 97% similar protein with a particularly well-conserved putative ligand-binding domain. To search for physiologically occurring activators, we established a transcriptional transactivation assay by stably expressing in CHO cells a chimera of rat PPAR and the human glucocorticoid receptor that activates expression of the placental alkaline phosphatase reporter gene under the control of the mouse mammary tumor virus promoter. Testing of compounds related to lipid metabolism or peroxisomal proliferation revealed that 150 microM concentrations of arachidonic or linoleic acid but not of dehydroepiandrosterone, cholesterol, or 25-hydroxy-cholesterol, activate the receptor chimera. In addition, saturated fatty acids induce the reporter gene. Shortening the chain length to n = 6 or introduction of an omega-terminal carboxylic group abolished the activation potential of the fatty acid. In conclusion, the present results indicate that fatty acids can regulate gene expression mediated by a member of the steroid nuclear receptor superfamily. Images PMID:1316614

  12. Radiotherapy-induced anti-tumor immunity contributes to the therapeutic efficacy of irradiation and can be augmented by CTLA-4 blockade in a mouse model.

    Directory of Open Access Journals (Sweden)

    Yuya Yoshimoto

    Full Text Available PURPOSE: There is growing evidence that tumor-specific immune responses play an important role in anti-cancer therapy, including radiotherapy. Using mouse tumor models we demonstrate that irradiation-induced anti-tumor immunity is essential for the therapeutic efficacy of irradiation and can be augmented by modulation of cytotoxic T lymphocyte (CTL activity. METHODS AND MATERIALS: C57BL/6 mice, syngeneic EL4 lymphoma cells, and Lewis lung carcinoma (LL/C cells were used. Cells were injected into the right femurs of mice. Ten days after inoculation, tumors were treated with 30 Gy of local X-ray irradiation and their growth was subsequently measured. The effect of irradiation on tumor growth delay (TGD was defined as the time (in days for tumors to grow to 500 mm3 in the treated group minus that of the untreated group. Cytokine production and serum antibodies were measured by ELISA and flow cytometry. RESULTS: In the EL4 tumor model, tumors were locally controlled by X-ray irradiation and re-introduced EL4 cells were completely rejected. Mouse EL4-specific systemic immunity was confirmed by splenocyte cytokine production and detection of tumor-specific IgG1 antibodies. In the LL/C tumor model, X-ray irradiation also significantly delayed tumor growth (TGD: 15.4 days and prolonged median survival time (MST to 59 days (versus 28 days in the non-irradiated group. CD8(+ cell depletion using an anti-CD8 antibody significantly decreased the therapeutic efficacy of irradiation (TGD, 8.7 days; MST, 49 days. Next, we examined whether T cell modulation affected the efficacy of radiotherapy. An anti-CTLA-4 antibody significantly increased the anti-tumor activity of radiotherapy (TGD was prolonged from 13.1 to 19.5 days, while anti-FR4 and anti-GITR antibodies did not affect efficacy. CONCLUSIONS: Our results indicate that tumor-specific immune responses play an important role in the therapeutic efficacy of irradiation. Immunomodulation, including CTLA-4

  13. Radiotherapy-Induced Anti-Tumor Immunity Contributes to the Therapeutic Efficacy of Irradiation and Can Be Augmented by CTLA-4 Blockade in a Mouse Model

    Science.gov (United States)

    Yoshimoto, Yuya; Suzuki, Yoshiyuki; Mimura, Kousaku; Ando, Ken; Oike, Takahiro; Sato, Hiro; Okonogi, Noriyuki; Maruyama, Takanori; Izawa, Shinichiro; Noda, Shin-ei; Fujii, Hideki; Kono, Koji; Nakano, Takashi

    2014-01-01

    Purpose There is growing evidence that tumor-specific immune responses play an important role in anti-cancer therapy, including radiotherapy. Using mouse tumor models we demonstrate that irradiation-induced anti-tumor immunity is essential for the therapeutic efficacy of irradiation and can be augmented by modulation of cytotoxic T lymphocyte (CTL) activity. Methods and Materials C57BL/6 mice, syngeneic EL4 lymphoma cells, and Lewis lung carcinoma (LL/C) cells were used. Cells were injected into the right femurs of mice. Ten days after inoculation, tumors were treated with 30 Gy of local X-ray irradiation and their growth was subsequently measured. The effect of irradiation on tumor growth delay (TGD) was defined as the time (in days) for tumors to grow to 500 mm3 in the treated group minus that of the untreated group. Cytokine production and serum antibodies were measured by ELISA and flow cytometry. Results In the EL4 tumor model, tumors were locally controlled by X-ray irradiation and re-introduced EL4 cells were completely rejected. Mouse EL4-specific systemic immunity was confirmed by splenocyte cytokine production and detection of tumor-specific IgG1 antibodies. In the LL/C tumor model, X-ray irradiation also significantly delayed tumor growth (TGD: 15.4 days) and prolonged median survival time (MST) to 59 days (versus 28 days in the non-irradiated group). CD8(+) cell depletion using an anti-CD8 antibody significantly decreased the therapeutic efficacy of irradiation (TGD, 8.7 days; MST, 49 days). Next, we examined whether T cell modulation affected the efficacy of radiotherapy. An anti-CTLA-4 antibody significantly increased the anti-tumor activity of radiotherapy (TGD was prolonged from 13.1 to 19.5 days), while anti-FR4 and anti-GITR antibodies did not affect efficacy. Conclusions Our results indicate that tumor-specific immune responses play an important role in the therapeutic efficacy of irradiation. Immunomodulation, including CTLA-4 blockade, may be a

  14. Late division kinetics in relation to modification of protein synthesis in mouse eggs blocked in the G2 phase after X-irradiation; and comment

    International Nuclear Information System (INIS)

    Grinfeld, S.; Gilles, J.; Jacquet, P.; Baugnet-Mahieu, L.; Rowley, R.

    1987-01-01

    Mouse zygotes (BALB/c blocked in the G 2 phase of the first cell cycle after X-irradiation were allowed to develop in culture medium. Delayed cleavage occurred at the same time in embryos exposed to 1 or 2 Gy and late division coincided with the second division in controls. Two dimensional electrophoresis showed that blocked irradiated embryos underwent the same modifications in protein synthesis as control embryos of the same age, except during first mitosis, for three polypeptide sets of 30, 35 and 45 kilodaltons molecular weight. The most remarkable difference between them was the appearance in cleaving controls of three spots at 35 kilodaltons that were absent in blocked irradiated embryos. It is assumed that blocked embryos 'missed' some signal necessary for cell division, but remained ready to cleave when a second signal occurred. Eggs from the BALB/c strain were particularly susceptible to this effect of X-irradiation but it was also found in eggs from other strains, irradiated with much higher doses. The accompanying comment by Rowley discusses the point of interruption of the control mechanism and the nature of the lesions involved. (author)

  15. Anti-bacterial immunity to Listeria monocytogenes in allogeneic bone marrow chimera in mice

    International Nuclear Information System (INIS)

    Onoe, K.; Good, R.A.; Yamamoto, K.

    1986-01-01

    Protection and delayed-type hypersensitivity (DTH) to the facultative intracellular bacterium Listeria monocytogenes (L.m.) were studied in allogeneic and syngeneic bone marrow chimeras. Lethally irradiated AKR (H-2k) mice were successfully reconstituted with marrow cells from C57BL/10 (B10) (H-2b), B10 H-2-recombinant strains or syngeneic mice. Irradiated AKR mice reconstituted with marrow cells from H-2-compatible B10.BR mice, [BR----AKR], as well as syngeneic marrow cells, [AKR----AKR], showed a normal level of responsiveness to the challenge stimulation with the listeria antigens when DTH was evaluated by footpad reactions. These mice also showed vigorous activities in acquired resistance to the L.m. By contrast, chimeric mice that had total or partial histoincompatibility at the H-2 determinants between donor and recipient, [B10----AKR], [B10.AQR----AKR], [B10.A(4R)----AKR], or [B10.A(5R)----AKR], were almost completely unresponsive in DTH and antibacterial immunity. However, when [B10----AKR] H-2-incompatible chimeras had been immunized with killed L.m. before challenge with live L.m., these mice manifested considerable DTH and resistance to L.m. These observations suggest that compatibility at the entire MHC between donor and recipient is required for bone marrow chimeras to be able to manifest DTH and protection against L.m. after a short-term immunization schedule. However, this requirement is overcome by a preceding or more prolonged period of immunization with L.m. antigens. These antigens, together with marrow-derived antigen-presenting cells, can then stimulate and expand cell populations that are restricted to the MHC (H-2) products of the donor type

  16. Connecting the Kuramoto Model and the Chimera State

    Science.gov (United States)

    Kotwal, Tejas; Jiang, Xin; Abrams, Daniel M.

    2017-12-01

    Since its discovery in 2002, the chimera state has frequently been described as a counterintuitive, puzzling phenomenon. The Kuramoto model, in contrast, has become a celebrated paradigm useful for understanding a range of phenomena related to phase transitions, synchronization, and network effects. Here we show that the chimera state can be understood as emerging naturally through a symmetry-breaking bifurcation from the Kuramoto model's partially synchronized state. Our analysis sheds light on recent observations of chimera states in laser arrays, chemical oscillators, and mechanical pendula.

  17. Estimation of dependence between mean of fractionation of photons and neutrons dose and intensity of post-irradiation reaction of mouse large intestine

    International Nuclear Information System (INIS)

    Gasinska, A.

    1995-01-01

    The aim of the work was verification of mouse large intestine tolerance on fractionated 250 kV X-rays and 2.3 MeV neutrons doses. Two cm of large intestine of mouse CBA/HT strain were irradiated with various fraction doses: from 0.25 to 35 Gy of X-rays and 0.05-12 Gy of neutrons. The measure of injury was handicap of intestine function. Early post-irradiation reaction was measured by loss of body weight (2-3 weeks after irradiation) and mouse mortality (till 2 months after irradiation, LD50/2). The late reaction was measured on the base of maximal body weight in 1 year period after irradiation, deformation of excrements (after 10 months) and death of animals (till 12. month after irradiation, LD50/12). Fractionation of X-ray dose influenced on decrease of intensification of late irradiation effects. After fractionation of neutrons this effect has not been observed. α/β coefficient for X-rays was 19.9 Gy [15.2; 27.0] for body weight nadir, 13.4 Gy [9.3; 19.5] for early mortality (LD50/2), 6.4 Gy [3.6;11.0] for maximal body weight and 6.9 [4.2; 10.8] for late mortality (LD50/12). Analysis of influence of low doses of photons 90.25-4 Gy) and neutrons (0.05-0.8 Gy) showed trend to reduction α/β for photons only (LD50/2=5.4 Gy; LD50/12=4.6 Gy). α/β coefficient for neutrons was defined by LQ model only for maximal body weight and was 19.9 Gy [9.5; 61.0]. In application of graphic method α/β for neutrons was 230 Gy for early and 48 Gy for late effects. Lower values of α/β coefficient for late irradiation effects for photon radiation demonstrate the big influence of fractionation of photons dose on large intestine tolerance (decrease intensity in all biological effects). Author did not observe increase of intestine tolerance in fractionation of neutrons dose. Effect of irradiation damages repair in interfraction pauses, measured by percent of regenerated dose (F r ) was much bigger for photons. For X-rays it was 50% for early and 63% for late effects. In case of

  18. Identification of radiation response genes and proteins from mouse pulmonary tissues after high-dose per fraction irradiation of limited lung volumes.

    Science.gov (United States)

    Jin, Hee; Jeon, Seulgi; Kang, Ga-Young; Lee, Hae-June; Cho, Jaeho; Lee, Yun-Sil

    2017-02-01

    The molecular effects of focal exposure of limited lung volumes to high-dose per fraction irradiation (HDFR) such as stereotactic body radiotherapy (SBRT) have not been fully characterized. In this study, we used such an irradiation system and identified the genes and proteins after HDFR to mouse lung, similar to those associated with human therapy. High focal radiation (90 Gy) was applied to a 3-mm volume of the left lung of C57BL6 mice using a small-animal stereotactic irradiator. As well as histological examination for lungs, a cDNA micro array using irradiated lung tissues and a protein array of sera were performed until 4 weeks after irradiation, and radiation-responsive genes and proteins were identified. For comparison, the long-term effects (12 months) of 20 Gy radiation wide-field dose to the left lung were also investigated. The genes ermap, epb4.2, cd200r3 (up regulation) and krt15, hoxc4, gdf2, cst9, cidec, and bnc1 (down-regulation) and the proteins of AIF, laminin, bNOS, HSP27, β-amyloid (upregulation), and calponin (downregulation) were identified as being responsive to 90 Gy HDFR. The gdf2, cst9, and cidec genes also responded to 20 Gy, suggesting that they are universal responsive genes in irradiated lungs. No universal proteins were identified in both 90 Gy and 20 Gy. Calponin, which was downregulated in protein antibody array analysis, showed a similar pattern in microarray data, suggesting a possible HDFR responsive serum biomarker that reflects gene alteration of irradiated lung tissue. These genes and proteins also responded to the lower doses of 20 Gy and 50 Gy HDFR. These results suggest that identified candidate genes and proteins are HDFR-specifically expressed in lung damage induced by HDFR relevant to SBRT in humans.

  19. A study on relation between nitroxyl radical reduction potency and X-ray irradiation on mouse lung using L-band electron spin resonance

    International Nuclear Information System (INIS)

    Taneike, Makoto; Sho, Keizen; Morita, Rikushi

    1999-01-01

    Changes in nitroxy radical reduction potency (''reduction potency''), caused by different doses and different number of fractions of X-ray irradiation were studied using a L-band electron spin resonance system on mouse lungs into which 4-hydroxy-2,2,6,6-tetramethylpiperidine-N-oxyl (hydroxy-TEMPO) was introduced through the trachea. The ''reduction potency'' lineally decreased as the irradiation dose increased from 1.0 to 5.0 Gy, but no further decrease was observed at higher doses of 7.5 and 10 Gy. The reduction potency'' dropped at 20 min after each irradiation, but it recovered to the control levels after 1 week in all 3 groups of single dose of 10 Gy, 3 fractions and 5 fractions in a similar manner. Although the levels of the ''reduction potency'' were kept high in the groups of fractionated irradiation through 1-4 weeks after irradiation, the levels dropped again in the single dose group at 1 week and the levels were kept significantly low until 4 weeks after irradiation. suggesting that the fractionation of X-ray irradiation would also be effective to prevent the deterioration of the ''reduction potency''. Pre-treatment with sufficient ascorbic acid inhibited the lowering effects of radiation on the ''reduction potency'' in a dose dependent manner. Furthermore the levels of the reduction potency'' ever elevated higher than those of controls with the large amount of ascorbic acid of 750 mg/kg or more, suggesting that the large amounts of ascorbic acid could prevent the adverse effects associated with radiation therapy for the lung malignancy. (author)

  20. The influence of mouse vaccination with endogenous retrovirus on the development of tumor incluced by γ-irradiation or 7,12-Dimethylbenz(a)anthrocene

    International Nuclear Information System (INIS)

    Mazurenko, N.P.; Yakovleva, L.S.; Shcherbak, N.P.; Pavlovskaya, A.I.; Zueva, Yu.N.

    1987-01-01

    Mouse vaccination with alive endogenous N-tropic virus OA-3 inhibited and decreased the development of the Rauscher leukemia in C57B1/6 mice (B-type) and SWR mice (N-type) as well as development 7,12-dimethyl benzanthracene (DMBA) induced tumours in mouse hybrides (neither N-, nor B-types). The effect of vaccination was DMBA- or MLV-P-dose-dependent. Vaccination with the same virus did not affect the incidence of γ-irradiaton-induced leukemia in CBA mice (N-type) and C57B1/6 mice while it increased twice the incidence of radiation leukemia in DBA mice (N-type). However, the incidence of thymomas lowered in radiaton leukemia-bearing vaccinated mice of all the 3 strains, which may result from inhibition of murine thymotropic endogenous virus reproduction. The data obtained indicate the participation of murine own endogenous viruses in DMBA- or γ-irradiation induced carcinogenesis

  1. Chimeras and Mirages of the Golden Horde

    Directory of Open Access Journals (Sweden)

    V.A. Ivanov

    2014-01-01

    Full Text Available The article examines the problem of so-called “imperial culture” of the Golden Horde. The author analyzes the archaeological material regarding it as a component of “imperial culture”. The author evaluates the quality of the archaeological material as well as the breadth and intensity of its distribution among the population of the Golden Horde and the neighboring tribal areas, which the author considers a priori as consumers of this “imperial culture”. Based on this analysis, the author concludes that in general, the concept of “imperial culture” of the Golden Horde is a chimera. In turn, the expected powerful effect of “imperial culture” of the Golden Horde in the culture of neighboring peoples of the Urals and the Volga region is a mirage created by the imagination of researchers.

  2. Grid adaptation using chimera composite overlapping meshes

    Science.gov (United States)

    Kao, Kai-Hsiung; Liou, Meng-Sing; Chow, Chuen-Yen

    1994-01-01

    The objective of this paper is to perform grid adaptation using composite overlapping meshes in regions of large gradient to accurately capture the salient features during computation. The chimera grid scheme, a multiple overset mesh technique, is used in combination with a Navier-Stokes solver. The numerical solution is first converged to a steady state based on an initial coarse mesh. Solution-adaptive enhancement is then performed by using a secondary fine grid system which oversets on top of the base grid in the high-gradient region, but without requiring the mesh boundaries to join in any special way. Communications through boundary interfaces between those separated grids are carried out using trilinear interpolation. Application to the Euler equations for shock reflections and to shock wave/boundary layer interaction problem are tested. With the present method, the salient features are well-resolved.

  3. Grid adaption using Chimera composite overlapping meshes

    Science.gov (United States)

    Kao, Kai-Hsiung; Liou, Meng-Sing; Chow, Chuen-Yen

    1993-01-01

    The objective of this paper is to perform grid adaptation using composite over-lapping meshes in regions of large gradient to capture the salient features accurately during computation. The Chimera grid scheme, a multiple overset mesh technique, is used in combination with a Navier-Stokes solver. The numerical solution is first converged to a steady state based on an initial coarse mesh. Solution-adaptive enhancement is then performed by using a secondary fine grid system which oversets on top of the base grid in the high-gradient region, but without requiring the mesh boundaries to join in any special way. Communications through boundary interfaces between those separated grids are carried out using tri-linear interpolation. Applications to the Euler equations for shock reflections and to a shock wave/boundary layer interaction problem are tested. With the present method, the salient features are well resolved.

  4. Stable Chimeras and Independently Synchronizable Clusters

    Science.gov (United States)

    Cho, Young Sul; Nishikawa, Takashi; Motter, Adilson E.

    2017-08-01

    Cluster synchronization is a phenomenon in which a network self-organizes into a pattern of synchronized sets. It has been shown that diverse patterns of stable cluster synchronization can be captured by symmetries of the network. Here, we establish a theoretical basis to divide an arbitrary pattern of symmetry clusters into independently synchronizable cluster sets, in which the synchronization stability of the individual clusters in each set is decoupled from that in all the other sets. Using this framework, we suggest a new approach to find permanently stable chimera states by capturing two or more symmetry clusters—at least one stable and one unstable—that compose the entire fully symmetric network.

  5. Application of Chimera Composite Grid Scheme to Ship Appendages

    National Research Council Canada - National Science Library

    Lin, Cheng-Wen

    1995-01-01

    .... The chimera scheme of grid generation uses a system of relatively simple grids. The grids each define a particular component of the overall geometry, making the initial grid generation much simpler...

  6. Is repulsion good for the health of chimeras?

    Science.gov (United States)

    Jalan, Sarika; Ghosh, Saptarshi; Patra, Bibhabasu

    2017-10-01

    Yes! Very much so. A chimera state refers to the coexistence of a coherent-incoherent dynamical evolution of identically coupled oscillators. We investigate the impact of multiplexing of a layer having repulsively coupled oscillators on the occurrence of chimeras in the layer having attractively coupled identical oscillators. We report that there exists an enhancement in the appearance of the chimera state in one layer of the multiplex network in the presence of repulsive coupling in the other layer. Furthermore, we show that a small amount of inhibition or repulsive coupling in one layer is sufficient to yield the chimera state in another layer by destroying its synchronized behavior. These results can be used to obtain insight into dynamical behaviors of those systems where both attractive and repulsive couplings exist among their constituents.

  7. Navier-Stokes Computations of Sabot Discard Using Chimera Scheme

    National Research Council Canada - National Science Library

    Ferry, E

    1997-01-01

    .... Numerical flow field computations have been made for various orientations and locations of sabots using an unsteady, zonal Navier-Stokes code and the Chimera composite grid discretization technique at M = 4.0 and alpha = 0...

  8. Chimera States in Two Populations with Heterogeneous Phase-lag

    DEFF Research Database (Denmark)

    Martens, Erik Andreas; Bick, Christian; Panaggio, Mark

    2016-01-01

    The simplest network of coupled phase-oscillators exhibiting chimera states is given by two populations with disparate intra- and inter-population coupling strengths. We explore the effects of heterogeneous coupling phase-lags between the two populations. Such heterogeneity arises naturally......-uniform synchronization, including in-phase and anti-phase synchrony, full incoherence (splay state), chimera states with phase separation of 0 or π between populations, and states where both populations remain desynchronized. These desynchronized states exhibit stable, oscillatory, and even chaotic dynamics. Moreover......, we identify the bifurcations through which chimera and desynchronized states emerge. Stable chimera states and desynchronized solutions, which do not arise for homogeneous phase-lag parameters, emerge as a result of competition between synchronized in-phase, anti-phase equilibria, and fully...

  9. Optimal design of tweezer control for chimera states

    Science.gov (United States)

    Omelchenko, Iryna; Omel'chenko, Oleh E.; Zakharova, Anna; Schöll, Eckehard

    2018-01-01

    Chimera states are complex spatio-temporal patterns which consist of coexisting domains of spatially coherent and incoherent dynamics in systems of coupled oscillators. In small networks, chimera states usually exhibit short lifetimes and erratic drifting of the spatial position of the incoherent domain. A tweezer feedback control scheme can stabilize and fix the position of chimera states. We analyze the action of the tweezer control in small nonlocally coupled networks of Van der Pol and FitzHugh-Nagumo oscillators, and determine the ranges of optimal control parameters. We demonstrate that the tweezer control scheme allows for stabilization of chimera states with different shapes, and can be used as an instrument for controlling the coherent domains size, as well as the maximum average frequency difference of the oscillators.

  10. The effect of x-ray irradiation on proliferation and differentiation of epithelial cells in mouse skin

    International Nuclear Information System (INIS)

    Tanabe, Akira

    1980-01-01

    To elucidate radiation injuries and the recovery mechanism of epithelial cells exposed to 150 R or 450 R of x-ray, the epidermal proliferative unit (EPU) in the backs of mice was analysed histologically and dynamically by measuring the labelled index of cells with 3 H-thymidine and measuring differentiation index of cells. EPU was normal for 6 days after irradiation with both 150 R and 450 R. However, partial hyperplasia and EPU disorders in a range consistent with hyperplasia appeared in segmented preparations 7 days after irradiation. Both doses inhibited cell differentiation for 5 days after irradiation. Cell proliferation, which was higher than the normal rate, peaked 7 days after irradiation with 150 R and 9 days after irradiation with 540 R. Cell proliferation returned to normal 10 days after irradiation. DNA synthesis was inhibited one day after irradiation with both 150 R and 450 R, but it returned to normal 3 days after irradiation. There was an overshoot of DNA synthesis, but synthesis returned to normal 9 days after irradiation with 150 R and 12 days after irradiation with 450 R. EPU disorders returned to normal according to normalization of cell differentiation and DNA synthesis. (Tsunoda, M.)

  11. Up-regulation of calreticulin in mouse liver tissues after long-term irradiation with low-dose-rate gamma rays.

    Science.gov (United States)

    Yi, Lan; Hu, Nan; Yin, Jie; Sun, Jing; Mu, Hongxiang; Dai, Keren; Ding, Dexin

    2017-01-01

    The biological effects of low-dose or low-dose-rate ionizing radiation on normal tissues has attracted attention. Based on previous research, we observed the morphology of liver tissues of C57BL/6J mice that received irradiation dose rates increased. Additionally, differential protein expression in liver tissues was analyzed using a proteomics approach. Compared with the matched group in the 2D gel analysis of the irradiated groups, 69 proteins had ≥ 1.5-fold changes in expression. Twenty-three proteins were selected based on ≥2.5-fold change in expression, and 22 of them were meaningful for bioinformatics and protein fingerprinting analysis. These molecules were relevant to cytoskeleton processes, cell metabolism, biological defense, mitochondrial damage, detoxification and tumorigenesis. The results from real-time PCR and western blot (WB) analyses showed that calreticulin (CRT) was up-regulated in the irradiated groups, which indicates that CRT may be relevant to stress reactions when mouse livers are exposed to low-dose irradiation and that low-dose-rate ionizing radiation may pose a cancer risk. The CRT protein can be a potential candidate for low-dose or low-dose-rate ionizing radiation early-warning biomarkers. However, the underlying mechanism requires further investigation.

  12. Chimera states in bipartite networks of FitzHugh-Nagumo oscillators

    Science.gov (United States)

    Wu, Zhi-Min; Cheng, Hong-Yan; Feng, Yuee; Li, Hai-Hong; Dai, Qiong-Lin; Yang, Jun-Zhong

    2018-04-01

    Chimera states consisting of spatially coherent and incoherent domains have been observed in different topologies such as rings, spheres, and complex networks. In this paper, we investigate bipartite networks of nonlocally coupled FitzHugh-Nagumo (FHN) oscillators in which the units are allocated evenly to two layers, and FHN units interact with each other only when they are in different layers. We report the existence of chimera states in bipartite networks. Owing to the interplay between chimera states in the two layers, many types of chimera states such as in-phase chimera states, antiphase chimera states, and out-of-phase chimera states are classified. Stability diagrams of several typical chimera states in the coupling strength-coupling radius plane, which show strong multistability of chimera states, are explored.

  13. The effect of caffeine on p53-dependent radioresponses in undifferentiated mouse embryonal carcinoma cells after X-ray and UV-irradiations

    International Nuclear Information System (INIS)

    Taga, Masataka; Shiraishi, Kazunori; Shimura, Tsutomu; Uematsu, Norio; Kato, Tomohisa; Niwa, Ohtsura; Nishimune, Yoshitake; Aizawa, Shinichi; Oshimura, Mitsuo

    2000-01-01

    The effect of caffeine was studied on the radioresponses of undifferentiated mouse embryonal carcinoma cells (EC cells) with or without the functional p53. The radioresponses studied included radiosensitivity, the activation of p53, apoptosis with characteristic DNA ladder formation and cell cycle progression. An undifferentiated mouse EC cell line, ECA2, and a newly established p53-deficient EC cell line, p53δ, were used in the present study. The status of the p53 gene did not significantly affect the colony survivals of undifferentiated EC cells to X-rays and UV. Although a post-irradiation treatment with caffeine sensitized both lines to X-rays marginally, the sensitization was prominent for UV regardless of the p53 status of the cells. The activation of a p53 responsible lacZ reporter construct was observed in stably transfected ECA2 cells after X-ray and UV irradiations. Caffeine suppressed the X-ray induced activation of the lacZ reporter, while it drastically enhanced the activation after UV irradiation. X-rays and UV readily triggered the apoptosis of ECA2 cells with the characteristic DNA ladder. Although UV-induced DNA ladder formation was enhanced by caffeine, that induced by X-rays was unaffected. Therefore, the effects of caffeine on the p53-dependent radioresponses were found to be agent specific: suppression for the X-ray induced and augmentation for the UV induced. In contrast to p53-proficient ECA2 cells, smear-like DNA degradation was observed for irradiated p53δ cells, suggesting the presence of a mode of cell death without DNA ladder formation. UV induction of the smear-like DNA degradation was enhanced in the presence of caffeine. Regardless of the state of the p53 gene, G1/S arrest was not observed in X-ray and UV irradiated EC cells. X-rays induced G2/M arrest in both lines, which was abrogated by caffeine, while G2/M arrest after UV was unaffected by a caffeine treatment. These results indicate that the radioresponses of undifferentiated

  14. The effect of caffeine on p53-dependent radioresponses in undifferentiated mouse embryonal carcinoma cells after X-ray and UV-irradiations

    Energy Technology Data Exchange (ETDEWEB)

    Taga, Masataka; Shiraishi, Kazunori; Shimura, Tsutomu; Uematsu, Norio; Kato, Tomohisa; Niwa, Ohtsura [Kyoto Univ. (Japan). Radiation Biology Center; Nishimune, Yoshitake; Aizawa, Shinichi; Oshimura, Mitsuo

    2000-09-01

    The effect of caffeine was studied on the radioresponses of undifferentiated mouse embryonal carcinoma cells (EC cells) with or without the functional p53. The radioresponses studied included radiosensitivity, the activation of p53, apoptosis with characteristic DNA ladder formation and cell cycle progression. An undifferentiated mouse EC cell line, ECA2, and a newly established p53-deficient EC cell line, p53{delta}, were used in the present study. The status of the p53 gene did not significantly affect the colony survivals of undifferentiated EC cells to X-rays and UV. Although a post-irradiation treatment with caffeine sensitized both lines to X-rays marginally, the sensitization was prominent for UV regardless of the p53 status of the cells. The activation of a p53 responsible lacZ reporter construct was observed in stably transfected ECA2 cells after X-ray and UV irradiations. Caffeine suppressed the X-ray induced activation of the lacZ reporter, while it drastically enhanced the activation after UV irradiation. X-rays and UV readily triggered the apoptosis of ECA2 cells with the characteristic DNA ladder. Although UV-induced DNA ladder formation was enhanced by caffeine, that induced by X-rays was unaffected. Therefore, the effects of caffeine on the p53-dependent radioresponses were found to be agent specific: suppression for the X-ray induced and augmentation for the UV induced. In contrast to p53-proficient ECA2 cells, smear-like DNA degradation was observed for irradiated p53{delta} cells, suggesting the presence of a mode of cell death without DNA ladder formation. UV induction of the smear-like DNA degradation was enhanced in the presence of caffeine. Regardless of the state of the p53 gene, G1/S arrest was not observed in X-ray and UV irradiated EC cells. X-rays induced G2/M arrest in both lines, which was abrogated by caffeine, while G2/M arrest after UV was unaffected by a caffeine treatment. These results indicate that the radioresponses of

  15. Plant chimeras: The good, the bad, and the 'Bizzaria'.

    Science.gov (United States)

    Frank, Margaret H; Chitwood, Daniel H

    2016-11-01

    Chimeras - organisms that are composed of cells of more than one genotype - captured the human imagination long before they were formally described and used in the laboratory. These organisms owe their namesake to a fire-breathing monster from Greek mythology that has the head of a lion, the body of a goat, and the tail of a serpent. The first description of a non-fictional chimera dates back to the middle of the seventeenth century when the Florentine gardener Pietro Nati discovered an adventitious shoot growing from the graft junction between sour orange (Citrus aurantium) and citron (Citrus medica). This perplexing chimera that grows with sectors phenotypically resembling each of the citrus progenitors inspired discussion and wonder from the scientific community and was fittingly named the 'Bizzaria'. Initially, the 'Bizzaria' was believed to be an asexual hybrid that formed from a cellular fusion between the grafted parents; however, in-depth cellular analyses carried out centuries later demonstrated that the 'Bizzaria', along with other chimeras, owe their unique sectored appearance to a conglomeration of cells from the two donors. Since this pivotal discovery at the turn of the twentieth century, chimeras have served both as tools and as unique biological phenomena that have contributed to our understanding of plant development at the cellular, tissue, and organismal level. Rapid advancements in genome sequencing technologies have enabled the establishment of new model species with novel morphological and developmental features that enable the generation of chimeric organisms. In this review, we show that genetic mosaic and chimera studies provide a technologically simple way to delve into the organismal, genetic, and genomic inner workings underlying the development of diverse model organisms. Moreover, we discuss the unique opportunity that chimeras present to explore universal principles governing intercellular communication and the coordination of

  16. Tools for integrated sequence-structure analysis with UCSF Chimera

    Directory of Open Access Journals (Sweden)

    Huang Conrad C

    2006-07-01

    Full Text Available Abstract Background Comparing related structures and viewing the structures in the context of sequence alignments are important tasks in protein structure-function research. While many programs exist for individual aspects of such work, there is a need for interactive visualization tools that: (a provide a deep integration of sequence and structure, far beyond mapping where a sequence region falls in the structure and vice versa; (b facilitate changing data of one type based on the other (for example, using only sequence-conserved residues to match structures, or adjusting a sequence alignment based on spatial fit; (c can be used with a researcher's own data, including arbitrary sequence alignments and annotations, closely or distantly related sets of proteins, etc.; and (d interoperate with each other and with a full complement of molecular graphics features. We describe enhancements to UCSF Chimera to achieve these goals. Results The molecular graphics program UCSF Chimera includes a suite of tools for interactive analyses of sequences and structures. Structures automatically associate with sequences in imported alignments, allowing many kinds of crosstalk. A novel method is provided to superimpose structures in the absence of a pre-existing sequence alignment. The method uses both sequence and secondary structure, and can match even structures with very low sequence identity. Another tool constructs structure-based sequence alignments from superpositions of two or more proteins. Chimera is designed to be extensible, and mechanisms for incorporating user-specific data without Chimera code development are also provided. Conclusion The tools described here apply to many problems involving comparison and analysis of protein structures and their sequences. Chimera includes complete documentation and is intended for use by a wide range of scientists, not just those in the computational disciplines. UCSF Chimera is free for non-commercial use and is

  17. Effect of vitamin E on preovulatory stage irradiated female mouse expressed as chromosomal abnormalities in generated embryos

    International Nuclear Information System (INIS)

    Salimi, M.; Mozdarani, H.

    2006-01-01

    The present study has been carried out to investigate the effects of preovulatory stage gamma-irradiation of female mice in the absence or presence of vitamin E on numerical chromosome abnormalities in 8-cell embryos after mating with non- irradiated males. Materials and Methods: The 8-11 weeks adult female NMRl mice were whole body irradiated at preovulatory stage (post PMSG injection and about 12-18 hours before Injecting HCG) with 4 Gy gamma-rays generated from a cobalt-60 source alone or in combination with 200 IU/kg vitamin E, intraperitoneally administered one hour prior to irradiation. Soon after HCG injection super ovulated irradiated females were mated with non-irradiated males. About 68-h post coitus (p.c), 8-cell embryos were flushed from the oviducts of pregnant mice and were fixed on slides using standard methods in order to screen for metaphase spreads and numerical chromosome abnormalities. Results: In control embryos, 8% of metaphase plates were aneuploidy whereas in preovulatory stage irradiated female mice, about 50% of metaphase plates of embryos showed numerical chromosome aberrations (P nd meiotic division. Reduction of the frequency of chromosome aberrations in the presence of vitamin E is probably due to antioxidant effects of this vitamin, and scavenging free radicals induced by gamma-rays in mice oocytes' environment

  18. Effect of time between x-irradiation and chemotherapy on the growth of three solid mouse tumors. IV. Actinomycin-d

    International Nuclear Information System (INIS)

    Twentyman, P.R.; Kallman, R.F.; Brown, J.M.

    1979-01-01

    Experiments have been carried out to determine the effect of different intervals between the administration of x-radiation (1200 rad) and actinomycin-D (200 μg/kg) on the growth delay produced in three mouse tumors. The tumors used were the EMT6 tumor in BALB/c mice and the KHT and RIF-1 sarcomas in C3H mice. All tumors were grown intramuscularly in the gastrocnemius muscle, and treatment was carried out at a mean tumor weight of 450 mg. Time to reach 2 x (for KHT) or 4 x (for EMT6 and RIF-1) treatment volume was used as the endpoint of response. The drug was administered intraperitoneally either 24, 6, or 2 hr before radiation, immediately before the start of radiation, or 3, 6, or 24 hr after radiation. All irradiations were carried out in unanesthetized mice. For a single administration at this dose level (close to the maximum tolerated dose) actinomycin-D did not produce a significant delay in the growth of any of the tumors. For the RIF-1 and KHT tumors, the growth delays produced by drug/radiation combinations generally were not significantly greater than that produced by irradiation alone. For the EMT6 tumor, great variability in the growth delays of combined modality groups seen, with mean growth delays significantly longer than predicted by the radiation alone data. No consistent dependence on timing between irradiation and drug administration was seen

  19. Differences in replicon behavior between x-irradiation-sensitive L5178Y mouse lymphoma cells and A-T fibroblasts using DNA fiber autoradiography

    International Nuclear Information System (INIS)

    Ockey, C.H.

    1983-01-01

    Replicon behavior in radiosensitive Ataxia telangiectasia (A-T) fibroblasts and mouse lymphoma L5178Y (LS) cells was studied by DNA fiber autoradiography. LS cells, irradiated at 13 Gy, showed a similar reduction in rate of DNA chain growth and initiation of replicons as did resistant (LR) cells. A progressive increase in the intensity of [ 3 H]TdR labeling of many replicons was observed after irradition in the LS cells, but not in LR cells. This indicated a reduced or absent endogenous dTTP supply after irradiation in the LS cells, implicating a defect in nucleoside precursor production. Irradiated normal human and A-T cells did not show this effect. After 2 Gy, the frequency of initiation of replicons into synthesis was temporarily reduced in the normal human but not in the A-T cells. After 20 Gy, the rate of DNA chain growth was preferentially reduced in the normal human cells, but an increase was observed in the A-T cells. This increased rate could be explained in terms of a normal supply of complexes involved in chain elongation being distributed over a reduced number of initiated replicon clusters in the A-T cells

  20. Contrasting feature in the repopulation of host-type T cells in the spleens of F1----P and P----F1 radiation bone marrow chimeras

    International Nuclear Information System (INIS)

    Hirokawa, K.; Sado, T.; Kubo, S.; Kamisaku, H.; Utsuyama, M.

    1986-01-01

    The regeneration and persistence of host- and donor-derived T cells were examined in the thymus as well as the spleen of mouse radiation bone marrow chimeras of two semiallogeneic combinations (F1----P, P----F1) with different Thy-1 markers on T cells of donor and host origins. An unexpectedly large number of host-type T cells were recovered from the spleens of F1----P chimeras, amounting to as high as 45 and 25% of total T cells at 6 and 14 weeks after bone marrow transplantation (BMT), respectively. To the contrary, the residual host-type T cells in the spleens of P----F1 chimeras disappeared quickly, resulting in less than 0.1% of total T cells at 6 weeks after BMT. It was also revealed that the number of host-type T cells in the spleens of F1----P chimeras decreased in proportion to increase of radiation dose given to the recipients

  1. Double-well chimeras in 2D lattice of chaotic bistable elements

    Science.gov (United States)

    Shepelev, I. A.; Bukh, A. V.; Vadivasova, T. E.; Anishchenko, V. S.; Zakharova, A.

    2018-01-01

    We investigate spatio-temporal dynamics of a 2D ensemble of nonlocally coupled chaotic cubic maps in a bistability regime. In particular, we perform a detailed study on the transition ;coherence - incoherence; for varying coupling strength for a fixed interaction radius. For the 2D ensemble we show the appearance of amplitude and phase chimera states previously reported for 1D ensembles of nonlocally coupled chaotic systems. Moreover, we uncover a novel type of chimera state, double-well chimera, which occurs due to the interplay of the bistability of the local dynamics and the 2D ensemble structure. Additionally, we find double-well chimera behavior for steady states which we call double-well chimera death. A distinguishing feature of chimera patterns observed in the lattice is that they mainly combine clusters of different chimera types: phase, amplitude and double-well chimeras.

  2. Morphological differences in the response of mouse small intestine to radiobiologically equivalent doses of X and neutron irradiation

    International Nuclear Information System (INIS)

    Carr, K.E.; Hamlet, R.; Nias, A.H.; Watt, C.

    1984-01-01

    A scale has been developed to describe the effects of radiation on small intestinal villi. The scale has been used to compare the damage done to the villi in the period 0-5 days after irradiation by X-irradiation or neutron irradiation, using 10 Gy X-rays and 5 Gy neutrons, doses which are radiobiologically equivalent when assessed by the microcolony assay method. Use of the scale indicates that the damage done to the villi by neutrons is greater than that produced by X-rays. This has implications for the interpretation of radiobiological equivalent doses (R.B.E.). Resin light microscopy and transmission electron microscopy (T.E.M.) have also been used to examine small intestinal damage after 10 Gy X-irradiation and 5 Gy neutron irradiation. Differences include variations in crypt shape, mitotic activity and the proportion of crypts which are heavily parasitised. As well as the differences in villous shape which have been reflected in the different values on the scoring system, there are also variations in the response of the constituent cells of the epithelial compartment of the villi. In general, the effect of the neutron irradiation is more severe than that of the X-rays, particularly as would be suggested by a simple quantitation of crypt regeneration

  3. Characterization of hemopoietic stem cell chimerism in antibody-facilitated bone marrow chimeras

    International Nuclear Information System (INIS)

    Francescutti, L.H.; Gambel, P.; Wegmann, T.G.

    1985-01-01

    The authors have previously described a model for bone marrow transplantation that involves preparation of the host with monoclonal antibody against class I or class II antigens instead of irradiation or cytotoxic drugs. This allows engraftment and subsequent repopulation of the host by donor tissue. They have previously reported on chimerism in the peripheral blood of P1----(P1 X P2)F1 animals. In this report, the authors describe the examination of the bone marrow and spleen stem cell chimerism of these antibody-facilitated (AF) chimeras, by determining, with an isozyme assay, the phenotype of methylcellulose colonies grown from stem cells. They have found a correlation between peripheral blood chimerism and the stem cell constitution of both spleen and bone marrow. The peripheral blood chimerism also correlates with the level of chimerism in macrophages derived from peritoneal exudate cells. These findings indicate that assaying the peripheral blood of such chimeras provides an excellent indication of the degree of chimerism at the stem cell level and stands in sharp contrast to the level of chimerism in certain lymphoid compartments

  4. Survival of allografts from bone marrow donors in temporary dog radiation chimeras

    International Nuclear Information System (INIS)

    Vriesendorp, H.M.

    Complete radiation chimeras accept indefinitely a skin or a kidney graft from the bone marrow (BM) donor. The advantages of this method of inducing graft acceptance are that it does not require the use of toxic post-operative immunosuppressive agents and that the immune reactivity against antigens other than the ones carried by the BM donor remains intact. The disadvantages of this approach are that supralethal total body irradiation (TBI) causes toxicity and that allogeneic BM cells can cause lethal Graft versus Host reactions. Attempts were made to diminish the significance of these disadvantages by using lower dose TBI and giving fewer BM cells. It is shown that, in dogs, 7.5 Gy TBI followed by 4 X 10 8 BM cells.kg -1 body weight of a DLA identical sibling leads to the development of complete radiation chimeras. The exclusive presence of donor type haemopoiesis can be demonstrated by determinations of 'informative' genetic markers, i.e., markers that show different genotypes in donor and recipient. (Auth.)

  5. Chimera states in coupled Kuramoto oscillators with inertia

    International Nuclear Information System (INIS)

    Olmi, Simona

    2015-01-01

    The dynamics of two symmetrically coupled populations of rotators is studied for different values of the inertia. The system is characterized by different types of solutions, which all coexist with the fully synchronized state. At small inertia, the system is no more chaotic and one observes mainly quasi-periodic chimeras, while the usual (stationary) chimera state is not anymore observable. At large inertia, one observes two different kind of chaotic solutions with broken symmetry: the intermittent chaotic chimera, characterized by a synchronized population and a population displaying a turbulent behaviour, and a second state where the two populations are both chaotic but whose dynamics adhere to two different macroscopic attractors. The intermittent chaotic chimeras are characterized by a finite life-time, whose duration increases as a power-law with the system size and the inertia value. Moreover, the chaotic population exhibits clear intermittent behavior, displaying a laminar phase where the two populations tend to synchronize, and a turbulent phase where the macroscopic motion of one population is definitely erratic. In the thermodynamic limit, these states survive for infinite time and the laminar regimes tends to disappear, thus giving rise to stationary chaotic solutions with broken symmetry contrary to what observed for chaotic chimeras on a ring geometry

  6. Chimera states in coupled Kuramoto oscillators with inertia

    Energy Technology Data Exchange (ETDEWEB)

    Olmi, Simona, E-mail: simona.olmi@fi.isc.cnr.it [CNR - Consiglio Nazionale delle Ricerche - Istituto dei Sistemi Complessi, via Madonna del Piano 10, I-50019 Sesto Fiorentino (Italy); INFN Sez. Firenze, via Sansone, 1 - I-50019 Sesto Fiorentino (Italy)

    2015-12-15

    The dynamics of two symmetrically coupled populations of rotators is studied for different values of the inertia. The system is characterized by different types of solutions, which all coexist with the fully synchronized state. At small inertia, the system is no more chaotic and one observes mainly quasi-periodic chimeras, while the usual (stationary) chimera state is not anymore observable. At large inertia, one observes two different kind of chaotic solutions with broken symmetry: the intermittent chaotic chimera, characterized by a synchronized population and a population displaying a turbulent behaviour, and a second state where the two populations are both chaotic but whose dynamics adhere to two different macroscopic attractors. The intermittent chaotic chimeras are characterized by a finite life-time, whose duration increases as a power-law with the system size and the inertia value. Moreover, the chaotic population exhibits clear intermittent behavior, displaying a laminar phase where the two populations tend to synchronize, and a turbulent phase where the macroscopic motion of one population is definitely erratic. In the thermodynamic limit, these states survive for infinite time and the laminar regimes tends to disappear, thus giving rise to stationary chaotic solutions with broken symmetry contrary to what observed for chaotic chimeras on a ring geometry.

  7. Chimera states in coupled Kuramoto oscillators with inertia.

    Science.gov (United States)

    Olmi, Simona

    2015-12-01

    The dynamics of two symmetrically coupled populations of rotators is studied for different values of the inertia. The system is characterized by different types of solutions, which all coexist with the fully synchronized state. At small inertia, the system is no more chaotic and one observes mainly quasi-periodic chimeras, while the usual (stationary) chimera state is not anymore observable. At large inertia, one observes two different kind of chaotic solutions with broken symmetry: the intermittent chaotic chimera, characterized by a synchronized population and a population displaying a turbulent behaviour, and a second state where the two populations are both chaotic but whose dynamics adhere to two different macroscopic attractors. The intermittent chaotic chimeras are characterized by a finite life-time, whose duration increases as a power-law with the system size and the inertia value. Moreover, the chaotic population exhibits clear intermittent behavior, displaying a laminar phase where the two populations tend to synchronize, and a turbulent phase where the macroscopic motion of one population is definitely erratic. In the thermodynamic limit, these states survive for infinite time and the laminar regimes tends to disappear, thus giving rise to stationary chaotic solutions with broken symmetry contrary to what observed for chaotic chimeras on a ring geometry.

  8. Deterministic and stochastic control of chimera states in delayed feedback oscillator

    Energy Technology Data Exchange (ETDEWEB)

    Semenov, V. [Department of Physics, Saratov State University, Astrakhanskaya Str. 83, 410012 Saratov (Russian Federation); Zakharova, A.; Schöll, E. [Institut für Theoretische Physik, TU Berlin, Hardenbergstraße 36, 10623 Berlin (Germany); Maistrenko, Y. [Institute of Mathematics and Center for Medical and Biotechnical Research, NAS of Ukraine, Tereschenkivska Str. 3, 01601 Kyiv (Ukraine)

    2016-06-08

    Chimera states, characterized by the coexistence of regular and chaotic dynamics, are found in a nonlinear oscillator model with negative time-delayed feedback. The control of these chimera states by external periodic forcing is demonstrated by numerical simulations. Both deterministic and stochastic external periodic forcing are considered. It is shown that multi-cluster chimeras can be achieved by adjusting the external forcing frequency to appropriate resonance conditions. The constructive role of noise in the formation of a chimera states is shown.

  9. Booster irradiation to the spleen following total body irradiation. A new immunosuppressive approach for allogeneic bone marrow transplantation

    International Nuclear Information System (INIS)

    Lapidot, T.; Singer, T.S.; Salomon, O.; Terenzi, A.; Schwartz, E.; Reisner, Y.

    1988-01-01

    Graft rejection presents a major obstacle for transplantation of T cell-depleted bone marrow in HLA-mismatched patients. In a primate model, after conditioning exactly as for leukemia patients, it was shown that over 99% of the residual host clonable T cells are concentrated in the spleen on day 5 after completion of cytoreduction. We have now corroborated these findings in a mouse model. After 9-Gy total body irradiation (TBI), the total number of Thy-1.2+ cells in the spleen reaches a peak between days 3 and 4 after TBI. The T cell population is composed of both L3T4 (helper) and Lyt-2 (suppressor) T cells, the former being the major subpopulation. Specific booster irradiation to the spleen (5 Gy twice) on days 2 and 4 after TBI greatly enhances production of donor-type chimera after transplantation of T cell-depleted allogeneic bone marrow. Similar enhancement can be achieved by splenectomy on day 3 or 4 after TBI but not if splenectomy is performed 1 day before TBI or 1 day after TBI, strengthening the hypothesis that, after lethal TBI in mice, the remaining host T cells migrate from the periphery to the spleen. These results suggest that a delayed booster irradiation to the spleen may be beneficial as an additional immunosuppressive agent in the conditioning of leukemia patients, in order to reduce the incidence of bone marrow allograft rejection

  10. Cytotoxic effect of x-irradiation of mouse tumor cells in the presence of Korean ginseng extract

    Energy Technology Data Exchange (ETDEWEB)

    Kwon, Hyoung Cheol; Kim, Jin Ki; Kim, Jung Soo [College of Medicine, Chonbuk National Univ., Junju (Korea, Republic of); Choi, Dong Seong [College of Medicine, Woosuck Univ., Wanju (Korea, Republic of)

    2000-09-01

    We already reported the results that aqueous extract of Korean ginseng roots showed a marked cytotoxicity. In this study, we investigated whether combined ginseng product with X-irradiation increase the cytotoxicity of tumor cells than X-irradiation or not. Fifty gram of Korean ginseng powder mixed with 1 L of distilled water was extracted with reflux flask under condition of 100 .deg. C for 5 hrs. This aqueous ginseng extract was filtered, centrifuged and then was freezed under condition of -90 .deg. C for 16-18 hrs. The freezing extract was dried with freeze drier, and then diluted. X-irradiation was given to tumor cells by 6 MeV linear accelerator. The cytotoxicity of ginseng in vitro was evaluated from its ability to reduce the clonogenecity of fibrosarcoma (FSa ll) cells. In X-irradiation alone group, each 2, 4, 6 and 8 Gy was given to tumor cells. In X-irradiation with ginseng group, 0.2 mg/mL or ginseng extract was exposed to tumor cells for 1 hour before X-irradiation. The yield for 50 g of ginseng extract which was treated with freezing drier was 3.13 g(6.3%). Cytotoxicity in vitro was measured as survival fraction which was judged from the curve, at ginseng concentration of 0.001, 0.01, 0.1 and 1 mg/ml were 0.89{+-}0.04, 0.86{+-}0.06, 0.73{+-}0.01 and 0.09{+-}0.02, respectively. Survival fraction at X-irradiation alone of 2, 4, 6 and 8 Gy were 0.81{+-}0.07, 0.42{+-}0.08, 0.15{+-}0.02, 0.03{+-}0.01, respectively. But, survival fraction in combined group of X-irradiation and ginseng (0.2mg/mL) at each same radiation dose were 0.28{+-}0.01, 0.18{+-}0.03, 0.08{+-}0.02, 0.006{+-}0.002, respectively (p<0.05). The yield for ginseng extract which was treated with freezing drier was 6.3%. Cytotoxicity of Fsa II in combined ginseng with X-irradiation group was increased than that at X-irradiation alone group, and its enhancing effect seemed to be added.

  11. Cytotoxic effect of x-irradiation of mouse tumor cells in the presence of Korean ginseng extract

    International Nuclear Information System (INIS)

    Kwon, Hyoung Cheol; Kim, Jin Ki; Kim, Jung Soo; Choi, Dong Seong

    2000-01-01

    We already reported the results that aqueous extract of Korean ginseng roots showed a marked cytotoxicity. In this study, we investigated whether combined ginseng product with X-irradiation increase the cytotoxicity of tumor cells than X-irradiation or not. Fifty gram of Korean ginseng powder mixed with 1 L of distilled water was extracted with reflux flask under condition of 100 .deg. C for 5 hrs. This aqueous ginseng extract was filtered, centrifuged and then was freezed under condition of -90 .deg. C for 16-18 hrs. The freezing extract was dried with freeze drier, and then diluted. X-irradiation was given to tumor cells by 6 MeV linear accelerator. The cytotoxicity of ginseng in vitro was evaluated from its ability to reduce the clonogenecity of fibrosarcoma (FSa ll) cells. In X-irradiation alone group, each 2, 4, 6 and 8 Gy was given to tumor cells. In X-irradiation with ginseng group, 0.2 mg/mL or ginseng extract was exposed to tumor cells for 1 hour before X-irradiation. The yield for 50 g of ginseng extract which was treated with freezing drier was 3.13 g(6.3%). Cytotoxicity in vitro was measured as survival fraction which was judged from the curve, at ginseng concentration of 0.001, 0.01, 0.1 and 1 mg/ml were 0.89±0.04, 0.86±0.06, 0.73±0.01 and 0.09±0.02, respectively. Survival fraction at X-irradiation alone of 2, 4, 6 and 8 Gy were 0.81±0.07, 0.42±0.08, 0.15±0.02, 0.03±0.01, respectively. But, survival fraction in combined group of X-irradiation and ginseng (0.2mg/mL) at each same radiation dose were 0.28±0.01, 0.18±0.03, 0.08±0.02, 0.006±0.002, respectively (p<0.05). The yield for ginseng extract which was treated with freezing drier was 6.3%. Cytotoxicity of Fsa II in combined ginseng with X-irradiation group was increased than that at X-irradiation alone group, and its enhancing effect seemed to be added

  12. Mitigation of Radiation-Induced Epithelial Damage by the TLR5 Agonist Entolimod in a Mouse Model of Fractionated Head and Neck Irradiation.

    Science.gov (United States)

    Toshkov, Ilia A; Gleiberman, Anatoli S; Mett, Vadim L; Hutson, Alan D; Singh, Anurag K; Gudkov, Andrei V; Burdelya, Lyudmila G

    2017-05-01

    Radiation treatment of head and neck cancer frequently causes severe collateral damage to normal tissues including mouth mucosa, salivary glands and skin. This toxicity limits the radiation dose that can be delivered and affects the patient's quality of life. Previous studies in mice and nonhuman primates showed that entolimod, a toll-like receptor 5 (TLR5) agonist derived from bacterial flagellin, effectively reduced radiation damage to hematopoietic and gastrointestinal tissues in both total-body and local irradiation scenarios, with no protection of tumors. Here, using a mouse model, we analyzed the efficacy of entolimod administered before or after irradiation in reducing damage to normal tissues. Animals received local fractionated radiation to the head and neck area, thus modeling radiotherapy of head and neck cancer. Tissue damage was evaluated through histomorphological examination of samples collected at different time points up to four weeks, mice were exposed locally to five daily fractions of 5, 6 or 7 Gy. A semiquantitative scoring system was used to assess the severity of observed pathomorphological changes. In this model, radiation damage was most severe in the lips, tongue and skin, moderate in the upper esophagus and minor in salivary glands. The kinetics of injury appearance and recovery of normal morphology varied among tissues, with maximal damage to the tongue, esophagus and salivary glands developing at earlier times (days 8-11 postirradiation) relative to that of lip and skin mucosa (days 11-15 postirradiation). While both tested regimens of entolimod significantly reduced the extent of radiation damage and accelerated restoration of normal structure in all tissues analyzed, administration of entolimod 1 h after each irradiation was more effective than treatment 30 min before irradiation. These results support the potential clinical use of entolimod as an adjuvant for improving the therapeutic index of head and neck cancer radiotherapy by

  13. Radioprotective Effect of Propolis on the Blood Corpuscle of a Mouse by SEM after X-irradiation on the Whole Body

    International Nuclear Information System (INIS)

    Ji, Tae Jeong

    2008-01-01

    After x-ray 5 Gy radiation on the whole body of a mouse using a linear accelerator, its leucocyte, erythrocyte, and platelet were observed by SEM. Also, after injecting propolis into the abdominal cavity, the radio-protective effect of blood corpuscles was studied. The observation of micromorphology in blood corpuscles revealed that the number of leukocyte, erythrocyte, and thrombocyte decreased in the experimental group and the lump got together in blood corpuscles after 10 and 20 days. In RBC, crack or break on the surface and poikilosperocytes were observed. In the irradiation group, the size of leucocytes was smaller than that in control group and the number of villus at the verge substantially decreased. The blood corpuscles in the propolis group, however, had the similar results to control group.

  14. Radioprotective Effect of Propolis on the Blood Corpuscle of a Mouse by SEM after X-irradiation on the Whole Body

    Energy Technology Data Exchange (ETDEWEB)

    Ji, Tae Jeong [Dept. of Radiological Science, Kaya University, Kimhae (Korea, Republic of)

    2008-03-15

    After x-ray 5 Gy radiation on the whole body of a mouse using a linear accelerator, its leucocyte, erythrocyte, and platelet were observed by SEM. Also, after injecting propolis into the abdominal cavity, the radio-protective effect of blood corpuscles was studied. The observation of micromorphology in blood corpuscles revealed that the number of leukocyte, erythrocyte, and thrombocyte decreased in the experimental group and the lump got together in blood corpuscles after 10 and 20 days. In RBC, crack or break on the surface and poikilosperocytes were observed. In the irradiation group, the size of leucocytes was smaller than that in control group and the number of villus at the verge substantially decreased. The blood corpuscles in the propolis group, however, had the similar results to control group.

  15. Pulse shape method for the Chimera silicon detectors

    Energy Technology Data Exchange (ETDEWEB)

    Pagano, A.; Arena, N.; Cardella, G.; D' Andrea, M.; Filippo, E. de; Fichera, F.; Giudice, N.; Guardone, N.; Grimaldi, A.; Nicotra, D.; Papa, M.; Pirrone, S.; Politi, G.; Rapicavoli, C.; Rizza, G.; Russotto, P.; Sacca, G.; Urso, S.; Lanzano, G. [Catania Univ., INFN Catania and Dipartimento di Fisica e Astronomia (Italy); Alderighi, M.; Sechi, G. [INFN Milano and Istituto di Fisica Cosmica CNR, Milano (Italy); Amorini, F.; Anzalone, A.; Cali, C.; Campagna, V.; Cavallaro, S.; Di Stefano, A.; Giustolisi, F.; La Guidara, E.; Lanzalone, G.; Maiolino, C.; Porto, F.; Rizzo, F.; Salamone, S. [Catania Univ., INFN-LNS and Dipartimento di Fisica e Astronomia (Italy); Auditore, L.; Trifiro, A.; Trimarchi, M. [Messina Univ., INFN and Dipartimento di Fisica (Italy); Bassini, R.; Boiano, C.; Guazzoni, P.; Russo, S.; Sassi, M.; Zetta, L. [Milano Univ., INFN Milano and Dipartimento di Fisica (Italy); Blicharska, J.; Grzeszczuk, A. [Silesia Univ., Institute of Physics, Katowice (Poland); Chatterjee, M.B. [Saha Institute Of Nuclear Physics, Kolkata (India); Geraci, E.; Zipper, W. [Bologna Univ., INFN Bologna and Dipartimento di Fisica (Italy); Rosato, E.; Vigilante, M. [Napoli Univ., INFN and Dipartimento di Fisica (Italy); Schroder, W.U.; T-ke, J. [Rochester Univ., Dept. of Chemistry, Rochester, N.Y. (United States)

    2003-07-01

    Since January 2003, the 4{pi} CHIMERA (Charged Heavy Ions Mass and Energy Resolving Array) detector in its full configuration has successfully been operated at the 'Catania Laboratori Nazionali del Sud' (LNS) accelerator facility. The detector has been used with a variety of beams from the Superconducting Cyclotron in heavy-ion reaction studies at Fermi bombarding energies. Future experiments with a focus on isospin physics at Fermi energies, planned for both primary and less intense secondary particle beams, suggest the development of new and more versatile experimental particle identification methods. Recent achievements in implementing specific pulse shape particle identification methods for CHIMERA silicon detectors are reported. They suggest an upgrade of the present charge and mass identification capability of CHIMERA by a simple extension of the method. (authors)

  16. Chimera States in Continuous Media: Existence and Distinctness

    Science.gov (United States)

    Nicolaou, Zachary G.; Riecke, Hermann; Motter, Adilson E.

    2017-12-01

    The defining property of chimera states is the coexistence of coherent and incoherent domains in systems that are structurally and spatially homogeneous. The recent realization that such states might be common in oscillator networks raises the question of whether an analogous phenomenon can occur in continuous media. Here, we show that chimera states can exist in continuous systems even when the coupling is strictly local, as in many fluid and pattern forming media. Using the complex Ginzburg-Landau equation as a model system, we characterize chimera states consisting of a coherent domain of a frozen spiral structure and an incoherent domain of amplitude turbulence. We show that in this case, in contrast with discrete network systems, fluctuations in the local coupling field play a crucial role in limiting the coherent regions. We suggest these findings shed light on new possible forms of coexisting order and disorder in fluid systems.

  17. Mechanism of chimera formation during the Multiple Displacement Amplification reaction

    Directory of Open Access Journals (Sweden)

    Stockwell Timothy B

    2007-04-01

    Full Text Available Abstract Background Multiple Displacement Amplification (MDA is a method used for amplifying limiting DNA sources. The high molecular weight amplified DNA is ideal for DNA library construction. While this has enabled genomic sequencing from one or a few cells of unculturable microorganisms, the process is complicated by the tendency of MDA to generate chimeric DNA rearrangements in the amplified DNA. Determining the source of the DNA rearrangements would be an important step towards reducing or eliminating them. Results Here, we characterize the major types of chimeras formed by carrying out an MDA whole genome amplification from a single E. coli cell and sequencing by the 454 Life Sciences method. Analysis of 475 chimeras revealed the predominant reaction mechanisms that create the DNA rearrangements. The highly branched DNA synthesized in MDA can assume many alternative secondary structures. DNA strands extended on an initial template can be displaced becoming available to prime on a second template creating the chimeras. Evidence supports a model in which branch migration can displace 3'-ends freeing them to prime on the new templates. More than 85% of the resulting DNA rearrangements were inverted sequences with intervening deletions that the model predicts. Intramolecular rearrangements were favored, with displaced 3'-ends reannealing to single stranded 5'-strands contained within the same branched DNA molecule. In over 70% of the chimeric junctions, the 3' termini had initiated priming at complimentary sequences of 2–21 nucleotides (nts in the new templates. Conclusion Formation of chimeras is an important limitation to the MDA method, particularly for whole genome sequencing. Identification of the mechanism for chimera formation provides new insight into the MDA reaction and suggests methods to reduce chimeras. The 454 sequencing approach used here will provide a rapid method to assess the utility of reaction modifications.

  18. Differentiation and functional maturation of bone marrow-derived intestinal epithelial T cells expressing membrane T cell receptor in athymic radiation chimeras

    International Nuclear Information System (INIS)

    Mosley, R.L.; Styre, D.; Klein, J.R.

    1990-01-01

    The thymus dependency of murine intestinal intraepithelial lymphocytes (IEL) was studied in an athymic F1----parent radiation chimera model. IEL, although not splenic or lymph node lymphocytes, from athymic chimeras displayed normal levels of cells bearing the class-specific T cell Ag, CD4 and CD8; the TCR-associated molecule, CD3; and the Thy-1 Ag. Moreover, two-color flow cytometric analyses of IEL from athymic mice demonstrated regulated expression of T cell Ag characteristic of IEL subset populations from thymus-bearing mice. In immunoprecipitation experiments, surface TCR-alpha beta or TCR-gamma delta were expressed on IEL, although not on splenic lymphocytes, from athymic chimeras. That IEL from athymic chimeras constituted a population of functionally mature effector cells activated in situ, similar to IEL from thymus-bearing mice, was demonstrated by the presence of CD3-mediated lytic activity of athymic lethally irradiated bone marrow reconstituted IEL. These data provide compelling evidence that intestinal T cells do not require thymic influence for maturation and development, and demonstrate that the microenvironment of the intestinal epithelium is uniquely adapted to regulate IEL differentiation

  19. The effects of 60Co γ-ray irradiation on the cytoskeleton of mouse peritoneal macrophages and human peripheral blood monocytes in vitro

    International Nuclear Information System (INIS)

    Chen Xiaomei; Guo Yuhua; Yin Zhiwei; Mao Zijun

    1990-03-01

    The whole mount cell electron microscopy in combination with selective extraction method for preparing cytoskeletal framework was applied. Cy toskeleton prepared by Triton X-100 treatment of mouse peritoneal macrophages and human peripheral blood monocytes appeared in electron microscopy as a highly organized and interconnected three-dimensional matrix of different fibrous elements. Since such cytoskeletons are open membrane-free system, individual fibrous organizations can be identified by specific antibodies. An indirect immunogold procedure using monoclonal anti-tubulin or anti-actin antibodies was applied to visualize tubulin-or actin-containing structures. The three-dimensional visualization of Triton X-100 resistant cytoskeletons had been used to demonstrate that different doses of 60 Co γ-ray caused a distinctive and reproducible alterations of the cytoskeletons of intact mouse peritoneal macrophages and human peripheral blood monocytes in vitro. The results showed that there were some similar alterations with those caused by cytochalasin B and by colchicine. From these observations and other workers' studies, it's likely that 60 Co γ-ray irradiation may inhibit cytoplasmic microtubule and microfilament assembling

  20. Progress in Grid Generation: From Chimera to DRAGON Grids

    Science.gov (United States)

    Liou, Meng-Sing; Kao, Kai-Hsiung

    1994-01-01

    Hybrid grids, composed of structured and unstructured grids, combines the best features of both. The chimera method is a major stepstone toward a hybrid grid from which the present approach is evolved. The chimera grid composes a set of overlapped structured grids which are independently generated and body-fitted, yielding a high quality grid readily accessible for efficient solution schemes. The chimera method has been shown to be efficient to generate a grid about complex geometries and has been demonstrated to deliver accurate aerodynamic prediction of complex flows. While its geometrical flexibility is attractive, interpolation of data in the overlapped regions - which in today's practice in 3D is done in a nonconservative fashion, is not. In the present paper we propose a hybrid grid scheme that maximizes the advantages of the chimera scheme and adapts the strengths of the unstructured grid while at the same time keeps its weaknesses minimal. Like the chimera method, we first divide up the physical domain by a set of structured body-fitted grids which are separately generated and overlaid throughout a complex configuration. To eliminate any pure data manipulation which does not necessarily follow governing equations, we use non-structured grids only to directly replace the region of the arbitrarily overlapped grids. This new adaptation to the chimera thinking is coined the DRAGON grid. The nonstructured grid region sandwiched between the structured grids is limited in size, resulting in only a small increase in memory and computational effort. The DRAGON method has three important advantages: (1) preserving strengths of the chimera grid; (2) eliminating difficulties sometimes encountered in the chimera scheme, such as the orphan points and bad quality of interpolation stencils; and (3) making grid communication in a fully conservative and consistent manner insofar as the governing equations are concerned. To demonstrate its use, the governing equations are

  1. Chimera-like states in structured heterogeneous networks

    Science.gov (United States)

    Li, Bo; Saad, David

    2017-04-01

    Chimera-like states are manifested through the coexistence of synchronous and asynchronous dynamics and have been observed in various systems. To analyze the role of network topology in giving rise to chimera-like states, we study a heterogeneous network model comprising two groups of nodes, of high and low degrees of connectivity. The architecture facilitates the analysis of the system, which separates into a densely connected coherent group of nodes, perturbed by their sparsely connected drifting neighbors. It describes a synchronous behavior of the densely connected group and scaling properties of the induced perturbations.

  2. Protection of mouse hematopoietic stem cells by a preparation of herb mixture (hemoHIM) against whole body irradiation

    International Nuclear Information System (INIS)

    Jung, W. H.; Park, H. R.; Oh, H.; Jung, I. Y.; Cho, S. K.

    2002-01-01

    A preparation of herb mixture (HemoHIM) was designed from three medicinal herbs including Angelica gigantis Radix to protect gastrointestine, hematopoietic organs and immune system against radiation damage. In the present study, we investigated the radioprotective effects of HemoHIM on hematopoietic stem cells in γ-irradiated mice and the underlying mechanisms. The administration of HemoHIM significantly increased the formation of endogenous spleen colony and reduced apoptosis of bone marrow cells in γ-irradiated mice. These results showed that HemoHIM protected hematopoietic stem cells from irradiation. To investigate the mechanism of the protection, the effects of HemoHIM on expression of radioprotective cytokines was examined. HemoHIM increased the mRNA levels of IL-1β, TNF-α, SCF and IL-6 in bone marrow cells and peritoneal macrophages in vitro. In vivo administration of HemoHIM increased the mRNA levels of IL-1β, TNF-α in spleen. The examination of radical scavenging activity of HemoHIM as another mechanism revealed that HemoHIM was effective at scavenging DPPH radicals and hydroxyl radicals. From these results, it is suggested that HemoHIM exerts these radioprotective effects through the induction of radioprotective cytokines and/or through directly scavenging radicals produced by γ-irradiation

  3. Protection of mouse hematopoietic stem cells by a preparation of herb mixture (hemoHIM) against whole body irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Jung, W. H.; Park, H. R.; Oh, H.; Jung, I. Y.; Cho, S. K. [KAERI, Taejon (Korea, Republic of)

    2002-10-01

    A preparation of herb mixture (HemoHIM) was designed from three medicinal herbs including Angelica gigantis Radix to protect gastrointestine, hematopoietic organs and immune system against radiation damage. In the present study, we investigated the radioprotective effects of HemoHIM on hematopoietic stem cells in {gamma}-irradiated mice and the underlying mechanisms. The administration of HemoHIM significantly increased the formation of endogenous spleen colony and reduced apoptosis of bone marrow cells in {gamma}-irradiated mice. These results showed that HemoHIM protected hematopoietic stem cells from irradiation. To investigate the mechanism of the protection, the effects of HemoHIM on expression of radioprotective cytokines was examined. HemoHIM increased the mRNA levels of IL-1{beta}, TNF-{alpha}, SCF and IL-6 in bone marrow cells and peritoneal macrophages in vitro. In vivo administration of HemoHIM increased the mRNA levels of IL-1{beta}, TNF-{alpha} in spleen. The examination of radical scavenging activity of HemoHIM as another mechanism revealed that HemoHIM was effective at scavenging DPPH radicals and hydroxyl radicals. From these results, it is suggested that HemoHIM exerts these radioprotective effects through the induction of radioprotective cytokines and/or through directly scavenging radicals produced by {gamma}-irradiation.

  4. Sequential appearance of thymocyte subpopulations and T cell antigen receptor gene messages in the mouse thymus after sublethal irradiation

    International Nuclear Information System (INIS)

    Tomooka, S.; Matsuzaki, G.; Kishihara, K.; Tanaka, K.; Yoshikai, Y.; Taniguchi, K.; Himeno, K.; Nomoto, K.

    1987-01-01

    The sequential differentiation patterns of thymocyte were observed with cell surface phenotypes and the expression of T cell antigen receptor in 800 rad irradiated adult mice. Thymus was severely reduced in size and cell number by day 5 after whole body irradiation and rapidly recovered from day 7 to day 14. Surface marker analysis on day 5 after irradiation showed thymocytes with Thy-1low L3T4+/Lyt-2- dominantly existed and suggested that these cells were radioresistant-survived cells. On the other hand, thymocytes on day 7 were composed of a large number of Thy-1high L3T4+/Lyt-2+ blast-like cells and a relatively high proportion of Thy-1high L3T4-/Lyt-2- cells which expressed a large amount of gamma-chain gene messages but scarcely any alpha- and beta-chain gene messages similar to the fetal thymocytes. On day 14, thymocytes were composed mostly of Thy-1high H-2low L3T4+/Lyt-2+ subpopulation which expressed a remarkably low level of gamma-chain gene messages, and high levels of alpha- and beta-chain transcripts analogous to those of normal adult thymus. Taken together, intrathymic radioresistent stem cells for T thymocytes seem to proliferate and differentiate after irradiation with the same pattern as was seen in a fetal thymus development

  5. The determination of lymphoid cell chimerism using peripheral blood lymphocytes from murine bone marrow chimeras

    International Nuclear Information System (INIS)

    Skidmore, B.J.; Miller, L.S.

    1978-01-01

    A simple, rapid and accurate method was devised for determining lymphoid cell chimerism in bone marrow-reconstituted mice. Chimeras were produced by reconstituting lethally irradiated mice with semi-allogeneic bone marrow cells. Lymphocytes from the peripheral blood of individual chimeric mice were purified by sedimentation in dextran solution and differential flotation in Ficoll-Hypaque gradients. From 250-500 μl of blood, 1-7 x 10 5 cells were routinely obtained. The extent of chimerism was determined serologically by using peripheral blood lymphocytes as target cells in a dye exclusion microcytotoxicity assay. Using this new technique, approximately 80% of the reconstituted mice were found to be repopulated with lymphocytes of the donor type. (Auth.)

  6. Expression and localization of Smad4 protein in mouse testis after whole-body X-ray irradiation

    International Nuclear Information System (INIS)

    Zhu Huaping; Zhang Yuanqiang; Zhao Jie; Zhao Yong; Ma Jing; Hou Wugang; Qi Yuhong

    2005-01-01

    The work is to determine whether and where Transforming growth factor-betas downstream Signaling molecule Smad4 is expressed in the testes after whole-body X-ray irradiation and shed light on the mechanisms of Transforming growth factor-betas/Smad signal pathway mediates cell fate decisions following X-ray exposure. Five groups of adult BALB/c mice, with ten mice in each group, received whole-body of X-ray at dose levels of 0.1 Gy, 0.5 Gy, 1.0 Gy, 1.5 Gy and 2.0 Gy. They were sacrificed at 16 hour, 1 week, 2 weeks, 3 weeks and 4 weeks after the irradiation. Cellular localization and expression changes were examined by immunohistochemical ABC method. Quantitative analysis of the immunostaining was made by an image analysis system. In the seminiferous tubules, the expression of Smad4 was modulated by irradiation. The immunostaining showed that 16 hour post-irradiation, there was a significant decline in the Leydig cell, and it was dose and time depended. In addition, the immunolocalization showed that Smad4 was not exclusively localized in the cytoplasm of Leydig cells, but also localized in various Stages of spermatogenesis after the exposure, especially in premeiotic spermatogonia and primary spermatocytes. There was just a little expression in the 2.0 Gy group 16 h after the irradiation and the 1.0 Gy and 1.5 Gy groups at 2 weeks after the irradiation. Therefore in the 0.1 Gy to 2.0 Gy groups at 3 weeks after the irradiation, the immunostaining positive cells were significantly increased in spermatogonia and primary spermatocytes. There was no significant change in sertoli cells with different doses and different times after the exposure. The different expression patterns and change by dose and time of Smad4, suggest that TGF-β/Smad signal pathway may affect aspect after X-ray impairment and Smad4 may play an important role during these periods. (authors)

  7. Inhibition of DNA and protein synthesis in UV-irradiated mouse skin by 2-difluoromethylornithine, methylglyoxal bis(guanylhydrazone), and their combination

    Energy Technology Data Exchange (ETDEWEB)

    Kaepyaho, K.; Lauharanta, J.; Jaenne, J.

    1983-08-01

    Exposure of mouse skin to UVB irradiation greatly enhanced the biosynthesis and accumulation of putrescine and spermidine before or concomitantly with stimulation of epidermal macromolecular (DNA and protein) synthesis. Topical treatment of UV-exposed skin with 2 inhibitors of polyamine biosynthesis, 2-difluoromethylornithine (DFMO) and methylglyoxal bis(guanylhydrazone) (MGBG) prevented the enhanced epidermal accumulation of polyamines, especially spermidine, and also inhibited the incorporation of radioactive precursors into DNA and protein. When applied in combination, these 2 antimetabolites of polyamines produced an inhibition of macromolecular synthesis that was at least additive: (/sup 3/H)thymidine incorporation decreased by 80% and (/sup 14/C)leucine incorporation by 44% as compared with the UVB-irradiated control mice. A slight decrease in the ratio of (/sup 3/H)histidine/(/sup 14/C)leucine incorporation indicated that protein synthesis of the differentiating cell layers was also affected by the inhibitors. The effects of the combined DFMO and MGBG treatment were partially reversed by concomitant topical application of spermidine.

  8. Inhibition of DNA and protein synthesis in UV-irradiated mouse skin by 2-difluoromethylornithine, methylglyoxal bis(guanylhydrazone), and their combination

    International Nuclear Information System (INIS)

    Kaepyaho, K.; Lauharanta, J.; Jaenne, J.

    1983-01-01

    Exposure of mouse skin to UVB irradiation greatly enhanced the biosynthesis and accumulation of putrescine and spermidine before or concomitantly with stimulation of epidermal macromolecular (DNA and protein) synthesis. Topical treatment of UV-exposed skin with 2 inhibitors of polyamine biosynthesis, 2-difluoromethylornithine (DFMO) and methylglyoxal bis(guanylhydrazone) (MGBG) prevented the enhanced epidermal accumulation of polyamines, especially spermidine, and also inhibited the incorporation of radioactive precursors into DNA and protein. When applied in combination, these 2 antimetabolites of polyamines produced an inhibition of macromolecular synthesis that was at least additive: [ 3 H]thymidine incorporation decreased by 80% and [ 14 C]leucine incorporation by 44% as compared with the UVB-irradiated control mice. A slight decrease in the ratio of [ 3 H]histidine/[ 14 C]leucine incorporation indicated that protein synthesis of the differentiating cell layers was also affected by the inhibitors. The effects of the combined DFMO and MGBG treatment were partially reversed by concomitant topical application of spermidine

  9. Simultaneous establishment of monoclonal antibodies specific for either cyclobutane pyrimidine dimer or (6-4)photoproduct from the same mouse immunized with ultraviolet irradiated DNA

    International Nuclear Information System (INIS)

    Mori, Toshio; Nakane, Misa; Hattori, Tsuyoshi; Matsunaga, Tsukasa; Nikaido, Osamu; Ihara, Makoto

    1991-01-01

    Six new monoclonal antibodies (TDM-2, TDM-3, 64M-2, 64M-3 64M-4 and 64M-5) specific for ultraviolet (UV) induced DNA damage have been established. In the antibody characterization experiments, two TDM antibodies were found to show a dose-dependent binding to UV-irradiated DNA (UV-DNA), decrease of binding to UV-DNA after cyclobutane pyrimidine dimer photoreactivation, binding to DNA containing cyclobutane thymine dimers, and unchanged binding to UV-DNA after photoisomerization of (6-4)photoproducts to Dewar photoproducts. These results indicated that the epitope of TDM monoclonal antibodies was the cyclobutane pyrimidine dimer in DNA. On the other hand, four 64M antibodies were found to show a dose-dependent binding to UV-DNA, unchanged binding to UV-DNA after cyclobutane pyrimidine dimer photoreactivation, undetectable binding to DNA containing thymine dimers, and decrease of binding to UV-DNA after photoisomerization of (6-4)photoproducts. These results indicated that the epitope of 64M antibodies was the (6-4)photoproduct in DNA. This is the first report of the simultaneous establishment of monoclonal antibodies against the two different types of photolesions from the same mouse. By using these monoclonal antibodies, we have succeeded in measuring both cyclobutane pyrimidine dimers and (6-4)photoproducts in the DNA from human primary cells irradiated with physiological UV doses. (author)

  10. Mechanisms of tolerance in murine radiation bone marrow chimeras. II. Absence of nonspecific suppression in mature chimeras

    International Nuclear Information System (INIS)

    Auchincloss, H. Jr.; Sachs, D.H.

    1983-01-01

    Spleen cells from a series of allogeneic bone marrow chimeras were sensitized in vitro with stimulator cells from major histocompatibility complex recombinant strains of mice. The combinations were chosen such that both tolerated (host or donor) and nontolerated (third-party) antigens were present on the same stimulator cells in order to determine whether the tolerated host antigens might elicit nonspecific suppressor mechanisms affecting the cell-mediated lympholysis (CML) response to the nontolerated antigens. No evidence for such nonspecific suppression was obtained in several types of assays. Therefore, if suppressor mechanisms exist that mediate such tolerance in mature allogeneic chimeras then these mechanisms must be highly antigen-specific

  11. Characterization of host lymphoid cells in antibody-facilitated bone marrow chimeras

    International Nuclear Information System (INIS)

    McCarthy, S.A.; Griffith, I.J.; Gambel, P.; Francescutti, L.H.; Wegmann, T.G.

    1985-01-01

    The authors have produced stable murine antibody-facilitated (AF) chimeras by the simultaneous injection of P1 bone marrow cells and anti-P2 monoclonal antibody into normal (unirradiated) adult (P1 X P2)F1 recipients. These AF chimeras are healthy, long-lived, and exhibit no overt signs of graft-versus-host disease. They are immunocompetent and tolerant of host, P2-encoded alloantigens. Donor cell engraftment and takeover, monitored by glucosephosphate isomerase isozyme patterns, is usually complete (greater than 95%) in the peripheral blood, bone marrow, and hemopoietic stem cell compartments of long-term (greater than 3 months posttransplantation) AF chimeras. The authors report here, however, that splenic, lymph node, and thymic leukocytes of AF chimeras represent donor/host chimeric populations. Spleen cell populations of AF chimeras exhibit substantial chimera-to-chimera variation in the preponderant residual host cell type(s) present. Interpretations of the implications of these findings are discussed

  12. Numerical analysis of the chimera states in the multilayered network model

    Science.gov (United States)

    Goremyko, Mikhail V.; Maksimenko, Vladimir A.; Makarov, Vladimir V.; Ghosh, Dibakar; Bera, Bidesh K.; Dana, Syamal K.; Hramov, Alexander E.

    2017-03-01

    We numerically study the interaction between the ensembles of the Hindmarsh-Rose (HR) neuron systems, arranged in the multilayer network model. We have shown that the fully identical layers, demonstrated individually different chimera due to the initial mismatch, come to the identical chimera state with the increase of inter-layer coupling. Within the multilayer model we also consider the case, when the one layer demonstrates chimera state, while another layer exhibits coherent or incoherent dynamics. It has been shown that the interactions chimera-coherent state and chimera-incoherent state leads to the both excitation of chimera as from the ensemble of fully coherent or incoherent oscillators, and suppression of initially stable chimera state

  13. Scanning microscopic evaluation on the development of the cerebral cortex in embryonic mouse subjected to γ-irradiation

    International Nuclear Information System (INIS)

    Sun Xuezhi; Inouye, Minoru; Hayasaka, Shizu; Takagishi, Yoshiko; Yamamura, Hideki

    1995-01-01

    Morphological events occurring in the developing cerebral hemispheres of mice exposed to a single dose of 60 Co γ-irradiation 1.5 Gy on embryonic day 13 (E13) were evaluated by scanning microscope. Twenty-four hr after the exposure, both cell debris and surviving cells had poured out into the ventricular lumen. Radial glial fibers were more crumpled than in the controls. By day E15, proliferating cells in different stages of the cell cycle appeared in the ventricular zone. The glial fibers formed a network through the brain mantle. By E17 many migrating cells attached to the disorderly glial fibers appeared in the different layers of the thin cerebral mantle. These findings suggest that development of the glial fibers was interrupted as early as 24 hr after the single exposure, implying that irradiation on the developing brain may disrupt neuronal migration. (author)

  14. Use of dexpanthenol and aloe vera to influence the irradiation response of the oral mucous membrane (mouse)

    International Nuclear Information System (INIS)

    Schlichting, S.; Spekl, K.; Doerr, W.

    2004-01-01

    In summarising the outcome of the present study it can be said spraying the agent on the oral mucous membrane once a day had an effect on the incidence of mucous membrane ulceration in the case of both placebo and dexpanthenol treatment. However, there was no significant difference between placebo and dexpanthenol treatment, the only finding being a slight prolongation of latency time through aloe vera. These experimental findings give good reason to critically reconsider the clinical use of dexpanthenol as a supportive treatment for the prevention of radiogenic mucositis enoralis following irradiation of tumours in the head and neck region. However thorough oral lavage is an effective means of moderating the irradiation response of the oral mucous membrane [de

  15. Study on proliferative responses to host Ia antigens in allogeneic bone marrow chimera in mice: sequential analysis of the reactivity and characterization of the cells involved in the responses

    International Nuclear Information System (INIS)

    Iwabuchi, K.; Ogasawara, K.; Ogasawara, M.; Yasumizu, R.; Noguchi, M.; Geng, L.; Fujita, M.; Good, R.A.; Onoe, K.

    1987-01-01

    Irradiation bone marrow chimeras were established by reconstitution of lethally irradiated AKR mice with C57BL/10 marrow cells to permit serial analysis of the developing reactivities of lymphocytes from such chimeras, [B10----AKR], against donor, host, or third party antigens. We found that substantial proliferative responses to Ia antigens of the recipient strain and also to third party antigens were generated by the thymocytes obtained from the irradiation chimeras at an early stage after bone marrow reconstitution. The majority of the responding thymocytes had surfaces lacking demonstrable peanut agglutinin receptors and were donor type Thy-1+, Ly-2-, and L3T4+ in both anti-recipient and anti-third party MLR. In anti-host responses, however, Ly-2+ thymocytes seemed to be at least partially involved. This capacity of thymus cells to mount a response to antigens of the recipient strain declined shortly thereafter, whereas the capacity to mount MLR against third party antigens persisted. The spleen cells of [B10----AKR] chimeras at the same time developed a more durable capability to exhibit anti-host reactivities and a permanent capability of reacting to third party allo-antigens. The stimulator antigens were Ia molecules on the stimulator cells in both anti-recipient and anti-third party MLR. The responding splenocytes were of donor origin and most of them had Thy-1+, Ly-1+2-, and L3T4+ phenotype

  16. Book Review: Evolution's Chimera: Bats and the Marvel of ...

    African Journals Online (AJOL)

    Abstract. Book Title: Evolution's Chimera: Bats and the Marvel of Evolutionary Adaptation. Book Author: David Jacobs. 2016, University of Cape Town Press, Juta and Company (Pty) Ltd, PO Box 14373, Lansdowne 7779, Cape Town, South Africa Softcover, 204 pages. ISBN 978-1-77582-212-7. Price R299 ...

  17. La Chimera di Dino Campana e Altre Chimere

    Directory of Open Access Journals (Sweden)

    Lucia Wataghin

    2008-08-01

    Full Text Available O presente artigo contém considerações sobre resultados e problemáticas da reutilização de materiais da tradição literária em um dos mais celebrados poemas de Dino Campana, La Chimera.

  18. What's Wrong with Human/Nonhuman Chimera Research?

    Science.gov (United States)

    Hyun, Insoo

    2016-08-01

    The National Institutes of Health (NIH) is poised to lift its funding moratorium on research involving chimeric human/nonhuman embryos, pending further consideration by an NIH steering committee. The kinds of ethical concerns that seem to underlie this research and chimera research more generally can be adequately addressed.

  19. Use of fragmentation beams at LNS with CHIMERA detector

    Directory of Open Access Journals (Sweden)

    Gianí R.

    2012-07-01

    Full Text Available The recent intensity upgrade of the LNS fragmentation beam is discussed. The available beams, the tagging procedures and details on the beam quality are reported. The experimental program started with the CHIMERA detector using such beams is also discussed with preliminary results and future perspectives.

  20. Chimera: construction of chimeric sequences for phylogenetic analysis

    NARCIS (Netherlands)

    Leunissen, J.A.M.

    2003-01-01

    Chimera allows the construction of chimeric protein or nucleic acid sequence files by concatenating sequences from two or more sequence files in PHYLIP formats. It allows the user to interactively select genes and species from the input files. The concatenated result is stored to one single output

  1. Development of cassava periclinal chimera may boost production.

    Science.gov (United States)

    Bomfim, N; Nassar, N M A

    2014-02-10

    Plant periclinal chimeras are genotypic mosaics arranged concentrically. Trials to produce them to combine different species have been done, but pratical results have not been achieved. We report for the second time the development of a very productive interspecific periclinal chimera in cassava. It has very large edible roots up to 14 kg per plant at one year old compared to 2-3 kg in common varieties. The epidermal tissue formed was from Manihot esculenta cultivar UnB 032, and the subepidermal and internal tissue from the wild species, Manihot fortalezensis. We determined the origin of tissues by meiotic and mitotic chromosome counts, plant anatomy and morphology. Epidermal features displayed useful traits to deduce tissue origin: cell shape and size, trichome density and stomatal length. Chimera roots had a wholly tuberous and edible constitution with smaller starch granule size and similar distribution compared to cassava. Root size enlargement might have been due to an epigenetic effect. These results suggest a new line of improved crop based on the development of interspecific chimeras composed of different combinations of wild and cultivated species. It promises boosting cassava production through exceptional root enlargement.

  2. Resistance to BN myelogenous leukemia in rat radiation chimeras

    International Nuclear Information System (INIS)

    Singer, D.E.; Haynor, D.R.; Williams, R.M

    1980-01-01

    Lewis → LBNFl rat radiation chimeras showed marked resistance to transplanted BN myelogenous leukemia when compared to naive LBNFl, LBNFl → LBNFl, or BN → LBNFl. This occurred in the absence of overt graft versus host disease or of anti-BN response in mixed lymphocyte culture. Bone marrow specific antigens may serve as the target of the resistance mechanism. (author)

  3. What's Wrong with Human/Nonhuman Chimera Research?

    Directory of Open Access Journals (Sweden)

    Insoo Hyun

    2016-08-01

    Full Text Available The National Institutes of Health (NIH is poised to lift its funding moratorium on research involving chimeric human/nonhuman embryos, pending further consideration by an NIH steering committee. The kinds of ethical concerns that seem to underlie this research and chimera research more generally can be adequately addressed.

  4. Recovery of immune competence following sublethal irradiation: the role of the mouse strains, thymic function and aging

    International Nuclear Information System (INIS)

    Peterson, W.J.

    1976-01-01

    The bone marrow, thymus and lymphohematopoietic microenvironments are determining factors in recovery of immune competence following sublethal irradiation. Because of age-related degenerative changes in all of these parameters it was anticipated that immune competence of irradiated old mice would show an altered pattern of recovery. Therefore, three age groups (3-7, 15, and 23-34-months) of C57BL/6J mice were treated with either 250R, 500R or 600R. At various intervals thereafter their spleen cells were assessed for recovery of humoral and cell-mediated immunologic activity and for thymus derived (T-), bone marrow derived (B-) and stem-cell compartments. Two age groups (3-7 and 23-months) of C3H/Anf Cum mice were also treated with the two highest doses or irradiation and their spleen cells tested only for recovery of T- and B-cell compartments. The results showed that recovery of immune competence following 250R was independent of age

  5. Stage specificity and dose-response relationships for chromosome aberrations induced in mouse primary spermatocytes following X-irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Matsuda, Y.; Tobari, I.; Utsugi, T.

    1986-05-01

    In this study, dose-response relationships were examined for chromosome aberrations observed at diakinesis-metaphase I of spermatocytes with X-irradiation at various stages of meiosis (diplotene, mid-pachytene, zygotene and leptotene). The frequencies of cells with X-ray-induced chromosome aberrations increased with dose at all stages in the applied range of 0.5-3.0 Gy and tended to increase as the irradiated stages descended after leptotene stage. In three stages, the frequencies increased exponentially with dose, but the rates of induction of chromosome breaks were markedly different depending on the stages at which spermatocytes were irradiated with X-rays. The rate of induction was the highest at diplotene and the lowest at leptotene, suggesting that diplotene spermatocytes had the highest radiosensitivity to the induction of chromosome breaks, followed by pachytene, zygotene and leptotene spermatocytes in that order. The dose-response relationships fitted well to linear equations for deletion-type aberrations at each stage, and to linear-quadratic equations for exchange-type aberrations at all stages except for leptotene. At leptotene, the chromatid exchanges were hardly observed, the aberrations being mainly consisted of iso-chromatid fragments. On the contrary, chromatid exchanges and iso-chromatide deletions were mainly observed at later stages (zygotene-diplotene).

  6. Methylation changes of H19 gene in sperms of X-irradiated mouse and maintenance in offspring

    International Nuclear Information System (INIS)

    Zhu Bin; Huang Xinghua; Chen Jindong; Lu Yachao; Chen Ying; Zhao Jingyong

    2006-01-01

    The nature of imprinting is just differential methylation of imprinted genes. Unlike the non-imprinted genes, the methylation pattern of imprinted genes established during the period of gametogenesis remains unchangeable after fertilization and during embryo development. It implies that gametogenesis is the key stage for methylation pattern of imprinted genes. The imprinting interfered by exogenous factors during this stage could be inherited to offspring and cause genetic effect. Now many studies have proved that ionizing irradiation could disturb DNA methylation. Here we choose BALB/c mice as a research model and X-ray as interfering source to further clarify it. We discovered that the whole-body irradiation of X-ray to male BALB/c mice could influence the methylation pattern of H 19 gene in sperms, which resulted in some cytosines of partial CpG islands in the imprinting control region could not transform to methylated cytosines. Furthermore, by copulating the interfered male mice with normal female, we analyzed the promoter methylation pattern of H 19 in offspring fetal liver and compared the same to the pattern of male parent in sperms. We found that the majority of methylation changes in offspring liver were related to the ones in their parent sperms. Our data proved that the changes of the H 19 gene methylation pattern interfered by X-ray irradiation could be transmitted and maintained in First-generation offspring

  7. The effect of low exposure-rate gamma irradiation on T and B lymphocyte function in the mouse

    International Nuclear Information System (INIS)

    McDermott, C.E.; Gengozian, N.

    1980-01-01

    The effect of chronic irradiation on T and B cell numbers and function was studied in mice. Cobalt 60 gamma radiation at 6 R/hour reduced the numbers of anti-SRBC PFC in the spleen, with minimal levels recorded after total exposures of 1000 to 2000 R. Recovery was incomplete after 1000 R, reaching only 40 to 50 per cent of normal in four months and remaining at that level for the animal's lifetime. The long-term deficiency in PFC formation was not due to a quantitative lack of T or B cells since normal cell numbers were observed in the spleen 60 to 144 days after 1000 R. Adoptive transfer studies with combinations of bone marrow and thymus cells, or of splenic T and B cells, from normal and irradiated mice, revealed functional defects in both cell compartments during the first two months. Normal and near normal function of T and B cells occurred 100 days postirradiation, a time when the splenic in vitro response was still only 50 per cent of the controls. The latter observation suggests that the microenvironment of the chronically irradiated spleen alters factors regulating T and B cell interactions in response to a T-dependent antigen. (author)

  8. The leukaemogenic effect of whole-body irradiation of the mouse: Experimental work at the Radiobiological Research Unit, Harwell

    International Nuclear Information System (INIS)

    Mole, R.H.

    1960-01-01

    Mouse 'leukaemia' is a generic term which might well be replaced by the clumsier, but more accurate, 'malignant disease of reticular tissue'. There are a variety of cytologically definable types (reticulosarcoma, 'histiocytoma' or monocytic leukaemia, lymphosarcoma and lymphoid leukaemia, myeloid leukosis) and a variety of morbid anatomical patterns, but there is only an approximate correlation between morbid anatomy and cytological type. True leukaemia where the white blood cell count is raised and morphologically abnormal white cells are found in the blood) occurs but is relatively uncommon; leukaemoid blood pictures are also found. Normally the murine thymus persists for much of the reproductive life-span, atrophying only in middle age, instead of in early childhood as in man. This may be the reason why the anatomical region of the thymus is more often involved in leukaemia in younger than in older animals, and why 'thymic leukaemia' is a characteristically murine disease and does not seem to occur in man. A great deal of the experimental work on mouse leukaemia reported in the literature is concerned with 'thymic leukaemia,' and this is often considered to be synonymous with thymic lymphoma or lymphosarcoma. However, the anatomy of tumour masses in the superior mediastinum. not infrequently suggests that they are not truly thymic in origin and their cell type is often not lymphoid

  9. The leukaemogenic effect of whole-body irradiation of the mouse: Experimental work at the Radiobiological Research Unit, Harwell

    Energy Technology Data Exchange (ETDEWEB)

    Mole, R H

    1960-12-01

    Mouse 'leukaemia' is a generic term which might well be replaced by the clumsier, but more accurate, 'malignant disease of reticular tissue'. There are a variety of cytologically definable types (reticulosarcoma, 'histiocytoma' or monocytic leukaemia, lymphosarcoma and lymphoid leukaemia, myeloid leukosis) and a variety of morbid anatomical patterns, but there is only an approximate correlation between morbid anatomy and cytological type. True leukaemia where the white blood cell count is raised and morphologically abnormal white cells are found in the blood) occurs but is relatively uncommon; leukaemoid blood pictures are also found. Normally the murine thymus persists for much of the reproductive life-span, atrophying only in middle age, instead of in early childhood as in man. This may be the reason why the anatomical region of the thymus is more often involved in leukaemia in younger than in older animals, and why 'thymic leukaemia' is a characteristically murine disease and does not seem to occur in man. A great deal of the experimental work on mouse leukaemia reported in the literature is concerned with 'thymic leukaemia,' and this is often considered to be synonymous with thymic lymphoma or lymphosarcoma. However, the anatomy of tumour masses in the superior mediastinum. not infrequently suggests that they are not truly thymic in origin and their cell type is often not lymphoid.

  10. Recipient micro-environment does not dictate the Igh-V restriction specificity of T cell suppressor inducer factor (TsiF) from allogeneic bone marrow chimera in mice

    International Nuclear Information System (INIS)

    Noguchi, M.; Ogasawara, M.; Iwabuchi, K.; Osgasawara, K.; Ishihara, T.; Good, R.A.; Morikawa, K.; Onoe, K.

    1985-01-01

    The authors have ascertained previously from a study of fully allogeneic irradiation chimeras in mice that the H-2 restriction of the suppressor factor (Ly-2 T suppressor factor) is determined by the post-thymic environment protected by the donor cells, rather than by the thymic environment of the recipient. In the present study, the author analyzed differentiation influences that determine the Igh restriction specificities of the suppressor inducer T cell factor(s) (TsiF) that are produced by Ly-1+ splenic T cells in fully allogeneic bone marrow chimeras in mice. AKR mice that had been lethally irradiated and reconstituted with B10 marrow cells, [B10----AKR] chimeras, produced Ly-1 TsiF after hyper-immunization with sheep erythrocytes (SRBC) which suppressed antigen--specifically the primary antibody responses to SRBC that were generated in cells of the same Igh-Vb haplotype of donor strain and not those generated in cells of the recipient Igh-Va type. Similar results were obtained when Ly-1 TsiF from [B6----BALB/c] and [BALB/c----B6] chimeras were analyzed. Furthermore, the Ly-1 TsiF from [BALB/c----B6] chimeras suppressed the primary antibody responses of both BALB/c [H-2d, Igh-Va, Igh-Ca] and BAB-14 (H-2d, Igh-Va, Igh-Cb), but not those of CAL-20 (H-2d, Igh-Vd, Igh-Cd). These results demonstrate clearly that the Ly-1 TsiF from allogeneic bone marrow chimeras are donor Igh-V-restricted and are not influenced by the recipient micro-environment, presumably that were provided by the thymuses of the recipient mice

  11. Method for the cultivation of dispersed epithelial cells from mouse palatal mucosa and the effects of X-irradiation

    International Nuclear Information System (INIS)

    Malek, K.W.

    1976-01-01

    Cultivation of adult oral epithelium in vitro has been previously reported for limited periods of time. The present research work describes a method for establishing pure cultures of adult palatal epithelial cells which were viable for extended periods of time. In contrast with most published work, we utilized a cell dispersion technique to obtain suspensions consisting of epithelial cells grown in monolayers. Cultures were maintained by subculturing for continuous periods up to 72 days. The fibroblastic overgrowth which has been previously reported by others in their attempts to culture oral epithelium was prevented in the present culture system as shown by phase microscopy and preliminary electron microscopy studies. The cells in vitro mainly displayed the normal morphologic characteristics of cultured epithelial cells. As demonstrated by labelling with tritiated thymidine, the monolayers of palatal epithelial cells possessed a high rate of DNA synthesis. Karyotypes of the cultured cells showed a high percentage of normal displays of chromosomal morphology. The number of spontaneous aberrations observed in our in vitro system were most likely the result of labilities induced by the conditions of cell culture rather than a reflection of the situation in vivo. Another part of the research dealt with the effects of exposure levels of 1R, 5R, and 10R of X-irradiation (within the clinical range for the dental patient) on the palatal epithelial cells grown in vitro over a short period of time. Our studies reveal that higher percentages of heteroploidy occur in comparison to normal non-irradiated cultures. A significant increase in the number of induced chromosomal aberrations as a result of low level exposure to X-rays was also observed in such cultures in comparison to those seen in non-irradiated control samples

  12. Migration of polypotent hemopoietic stem cells from mouse bone marrow shielded during irradiation after hemorrhage and transfusion of syngeneic erythrocytes

    International Nuclear Information System (INIS)

    Kozlov, V.A.; Lozovoj, V.P.; Zhuravkin, I.N.

    1977-01-01

    CBA mice have been X-irradiated with a lethal dose of 850 R. The rate of migration of hemopoietic stem cells has been studied at varying times after hemorrhage and administration of syngeneic erythrocytes. Hemorrhage has been shown to enhance markedly the stem cell migration. Administration of syngeneic erythrocytes decreases considerably the rate of stem cell migaration. It is suggested that the erythropoiesis stimulation is responsible for the increased yield of stem cells from the bone marrow, and that the suppression of erythropoiesis inhibits migration of the stem cells

  13. Clonal deletion: A mechanism of tolerance in mixed bone marrow chimeras

    International Nuclear Information System (INIS)

    Yu, J.C.; Webster, M.; Fox, I.J.

    1990-01-01

    The mechanism of antigen-specific immunologic unresponsiveness which results from lethal irradiation and mixed (syngeneic-allogeneic) bone marrow cell (BMC) reconstitution is unknown. To determine whether clonal deletion is the mechanism of tolerance in this model, monoclonal antibody (Mab) RR-4-4, specific for a T-cell receptor (V beta 6) reactive against the minor alloantigen MLsa, was employed. Six-week-old B10 mice (H-2b, Mlsb, Thyl.2) were tolerized to AKR antigens (H-2k, Mlsa, Thyl.1) by whole body irradiation (950 R) and iv infusion of T-cell-depleted (TCD) B10 BMC + non-TCD AKR BMC. Chimerism and antigen-specific tolerance were documented by flow microfluorometry (FMF), skin grafting, mixed lymphocyte reaction, and cell-mediated lympholysis. When tolerant B10 mice (n = 15) had accepted AKR skin grafts for greater than 100 days, these animals were studied for the presence of host V beta 6+ T cells using Mab RR-4-4. FMF revealed that 0-5% of host (B10) lymph node and spleen cells from chimeras were V beta 6+ while 15-20% of lymph node and spleen cells from control B10 mice expressed V beta 6. These data demonstrate that clonal deletion occurs in the lethal irradiation-mixed reconstitution model as evidenced by the near total elimination of Mlsa-reactive V beta 6+ T cells and suggest that it maybe a mechanism responsible for tolerance in adult mice

  14. In vivo UVA irradiation of mouse is more efficient in promoting pulmonary melanoma metastasis than in vitro

    Science.gov (United States)

    2011-01-01

    Background We have previously shown in vitro that UVA increases the adhesiveness of mouse B16-F1 melanoma cells to endothelium. We have also shown in vivo that UVA exposure of C57BL/6 mice, i.v. injected with B16-F1 cells, increases formation of pulmonary colonies of melanoma. The aim of the present animal study was to confirm the previously observed in vivo UVA effect and to determine whether in vitro UVA-exposure of melanoma cells, prior the i.v. injection, will have an enhancing effect on the pulmonary colonization capacity of melanoma cells. As a second aim, UVA-derived immunosuppression was determined. Methods Mice were i.v. injected with B16-F1 cells into the tail vein and then immediately exposed to UVA. Alternatively, to study the effect of UVA-induced adhesiveness on the colonization capacity of B16-F1 melanoma, cells were in vitro exposed prior to i.v. injection. Fourteen days after injection, lungs were collected and the number of pulmonary nodules was determined under dissecting microscope. The UVA-derived immunosuppression was measured by standard contact hypersensitivity assay. Results and Discussion Obtained results have confirmed that mice, i.v. injected with B16-F1 cells and thereafter exposed to UVA, developed 4-times more of melanoma colonies in lungs as compared with the UVA non-exposed group (p UVA-induced changes in the adhesive properties of melanoma cells do not alone account for the 4-fold increase in the pulmonary tumor formation. Instead, it suggests that some systemic effect in a mouse might be responsible for the increased metastasis formation. Indeed, UVA was found to induce moderate systemic immunosuppression, which effect might contribute to the UVA-induced melanoma metastasis in mice lungs. PMID:21645404

  15. Focal exposure of limited lung volumes to high-dose irradiation down-regulated organ development-related functions and up-regulated the immune response in mouse pulmonary tissues.

    Science.gov (United States)

    Kim, Bu-Yeo; Jin, Hee; Lee, Yoon-Jin; Kang, Ga-Young; Cho, Jaeho; Lee, Yun-Sil

    2016-01-27

    Despite the emergence of stereotactic body radiotherapy (SBRT) for treatment of medically inoperable early-stage non-small-cell lung cancer patients, the molecular effects of focal exposure of limited lung volumes to high-dose radiation have not been fully characterized. This study was designed to identify molecular changes induced by focal high-dose irradiation using a mouse model of SBRT. Central areas of the mouse left lung were focally-irradiated (3 mm in diameter) with a single high-dose of radiation (90 Gy). Temporal changes in gene expression in the irradiated and non-irradiated neighboring lung regions were analyzed by microarray. For comparison, the long-term effect (12 months) of 20 Gy radiation on a diffuse region of lung was also measured. The majority of genes were down-regulated in the focally-irradiated lung areas at 2 to 3 weeks after irradiation. This pattern of gene expression was clearly different than gene expression in the diffuse region of lungs exposed to low-dose radiation. Ontological and pathway analyses indicated these down-regulated genes were mainly associated with organ development. Although the number was small, genes that were up-regulated after focal irradiation were associated with immune-related functions. The temporal patterns of gene expression and the associated biological functions were also similar in non-irradiated neighboring lung regions, although statistical significance was greatly reduced when compared with those from focally-irradiated areas of the lung. From network analysis of temporally regulated genes, we identified inter-related modules associated with diverse functions, including organ development and the immune response, in both the focally-irradiated regions and non-irradiated neighboring lung regions. Focal exposure of lung tissue to high-dose radiation induced expression of genes associated with organ development and the immune response. This pattern of gene expression was also observed in non-irradiated

  16. Stable amplitude chimera states in a network of locally coupled Stuart-Landau oscillators

    Science.gov (United States)

    Premalatha, K.; Chandrasekar, V. K.; Senthilvelan, M.; Lakshmanan, M.

    2018-03-01

    We investigate the occurrence of collective dynamical states such as transient amplitude chimera, stable amplitude chimera, and imperfect breathing chimera states in a locally coupled network of Stuart-Landau oscillators. In an imperfect breathing chimera state, the synchronized group of oscillators exhibits oscillations with large amplitudes, while the desynchronized group of oscillators oscillates with small amplitudes, and this behavior of coexistence of synchronized and desynchronized oscillations fluctuates with time. Then, we analyze the stability of the amplitude chimera states under various circumstances, including variations in system parameters and coupling strength, and perturbations in the initial states of the oscillators. For an increase in the value of the system parameter, namely, the nonisochronicity parameter, the transient chimera state becomes a stable chimera state for a sufficiently large value of coupling strength. In addition, we also analyze the stability of these states by perturbing the initial states of the oscillators. We find that while a small perturbation allows one to perturb a large number of oscillators resulting in a stable amplitude chimera state, a large perturbation allows one to perturb a small number of oscillators to get a stable amplitude chimera state. We also find the stability of the transient and stable amplitude chimera states and traveling wave states for an appropriate number of oscillators using Floquet theory. In addition, we also find the stability of the incoherent oscillation death states.

  17. Effect of dose rate on residual γ-H2AX levels and frequency of micronuclei in X-irradiated mouse lymphocytes.

    Science.gov (United States)

    Turner, H C; Shuryak, I; Taveras, M; Bertucci, A; Perrier, J R; Chen, C; Elliston, C D; Johnson, G W; Smilenov, L B; Amundson, S A; Brenner, D J

    2015-03-01

    The biological risks associated with low-dose-rate (LDR) radiation exposures are not yet well defined. To assess the risk related to DNA damage, we compared the yields of two established biodosimetry end points, γ-H2AX and micronuclei (MNi), in peripheral mouse blood lymphocytes after prolonged in vivo exposure to LDR X rays (0.31 cGy/min) vs. acute high-dose-rate (HDR) exposure (1.03 Gy/min). C57BL/6 mice were total-body irradiated with 320 kVP X rays with doses of 0, 1.1, 2.2 and 4.45 Gy. Residual levels of total γ-H2AX fluorescence in lymphocytes isolated 24 h after the start of irradiation were assessed using indirect immunofluorescence methods. The terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay was used to determine apoptotic cell frequency in lymphocytes sampled at 24 h. Curve fitting analysis suggested that the dose response for γ-H2AX yields after acute exposures could be described by a linear dependence. In contrast, a linear-quadratic dose-response shape was more appropriate for LDR exposure (perhaps reflecting differences in repair time after different LDR doses). Dose-rate sparing effects (P effect across the dose range 24 h or 7 days post exposure. In conclusion, the γ-H2AX biomarker showed higher sensitivity to measure dose-rate effects after low-dose LDR X rays compared to MNi formation; however, confounding factors such as variable repair times post exposure, increased cell killing and cell cycle block likely contributed to the yields of MNi with accumulating doses of ionizing radiation.

  18. Induction of mouse mammary tumor virus RNA in mammary tumors of BALB/c mice treated with urethane, x-irradiation, and hormones

    International Nuclear Information System (INIS)

    Michalides, R.; van Deemter, L.; Nusse, R.; Hageman, P.

    1979-01-01

    The involvement of mouse mammary tumor virus (MTV) in the development of mammary tumors of nonviral etiology in BALB/c mice was studied by measuring the levels of MTV RNA, MTV DNA, and MTV proteins in spontaneously arising and hormally, chemically, and/or physically induced mammary tumors of BALB/c females. The following results were obtained: (1) spontaneous mammary tumors contained very low levels of MTV RNA; 4 x 10 -6 % of the cytoplasmic RNA was MTV RNA. No MTV proteins could be demonstrated by using sensitive radioimmunoassays for MTV proteins p27 and gp52. (2) Mammary tumors induced by treatments with urethane or x-irradiation alone contained higher levels of MTV RNA; these tumors contained 3- and 19-fold more MTV RNA, respectively, compared with spontaneous mammary tumors. (3) Mammary tumors induced by combined treatment with urethane and x-irradiation expressed high levels of MTV RNA in the mammary tumors; a 1,724-fold increase in MTV RNA content compared with spontaneous mammary tumors was observed. However, very low levels of MTV proteins gp52 and p27 were detected, suggesting some kind of impairment at the translation of MTV RNA. MTV RNA was also induced by this treatment in mammary glands and spleens, but not in the livers of tumor-bearing animals. (4) BALB/c females continuously exposed to prolactin contained high levels of MTV RNA and MTV proteins in stimulated mammary glands and in the hormonally induced mammary tumors. These findings suggest that MTV is not responsible for the maintenance and probably also not for the development of all murine mammary cancers

  19. Repair of mouse haemopoiesis at later times after long-term external (137Cs) and internal (3H) irradiation

    International Nuclear Information System (INIS)

    Luzanov, V.M.; Murzina, L.D.; Kirillova, E.N.

    1982-01-01

    In experiments on CBA mice it was shown that the haemopoiesis recovery was incomplete during 18 months after termination of internal exposure to tritium oxide or external γ-irradiation in the equivalent daily and cumulative doses. in mice given the radionuclide, the increment of CFUsub(s) and bone marrow nucleate cells was accompanied by leuko- and thrombocytopenia. In mice externally exposed to γ-rays, cytopenia did not develop at a lower content of CFUsub(s) and myelocaryocytes. It is suggested that the revealed diversions in the pattern of recovery of the haemopoiesis of mice of the compared groups are conditioned by the changes in functional activity of haemopoietic stem cells

  20. Developmental defects and genomic instability after x-irradiation of wild-type and genetically modified mouse pre-implantation and early post-implantation embryos

    International Nuclear Information System (INIS)

    Jacquet, P

    2012-01-01

    Results obtained from the end of the 1950s suggested that ionizing radiation could induce foetal malformations in some mouse strains when administered during early pre-implantation stages. Starting in 1989, data obtained in Germany also showed that radiation exposure during that period could lead to a genomic instability in the surviving foetuses. Furthermore, the same group reported that both malformations and genomic instability could be transmitted to the next generation foetuses after exposure of zygotes to relatively high doses of radiation. As such results were of concern for radiation protection, we investigated this in more detail during recent years, using mice with varying genetic backgrounds including mice heterozygous for mutations involved in important cellular processes like DNA repair, cell cycle regulation or apoptosis. The main parameters which were investigated included morphological development, genomic instability and gene expression in the irradiated embryos or their own progeny. The aim of this review is to critically reassess the results obtained in that field in the different laboratories and to try to draw general conclusions on the risks of developmental defects and genomic instability from an exposure of early embryos to moderate doses of ionizing radiation. Altogether and in the range of doses normally used in diagnostic radiology, the risk of induction of embryonic death and of congenital malformation following the irradiation of a newly fertilised egg is certainly very low when compared to the ‘spontaneous’ risks for such effects. Similarly, the risk of radiation induction of a genomic instability under such circumstances seems to be very small. However, this is not a reason to not apply some precaution principles when possible. One way of doing this is to restrict the use of higher dose examinations on all potentially pregnant women to the first ten days of their menstrual cycle when conception is very unlikely to have occurred

  1. A comparison of the survival (LD/sub 50/30/) of a number of inbred mouse strains after X and 60Co gamma irradiation

    International Nuclear Information System (INIS)

    Vacha, J.; Znojil, V.; Hola, J.; Sikulova, J.

    1984-01-01

    The value of LD/sub 50/30/ for X and 60 Co gamma radiation was ascertained for several inbred mouse strains and the significance of interstrain differences in these parameters determined. The rank order of strains according to LD/sub 50/30/ differs as between the two types of radiation with the exception of the strains BALB/c and B10.LP/Ph, which are the least resistant to radiation-induced lethality with both types of radiation. The strain C57BL/10ScSnPh is highly resistant to X irradiation. The relative biological effectiveness of 60 Co gamma radiation as compared with X-radiation from the point of view of lethality fluctuates between 0.748 and 0.952 in individual strains, with a mean value of 0.866 +- 0.033. The RBE values do not correlate with the radiosensitivity of the strain, but they do correlate with the relative contribution to erythropoiesis of the spleen. (author)

  2. Greater sparing of stromal progenitor cells than of haemopoietic stem cells in γ-irradiated mouse marrow using low dose-rates

    International Nuclear Information System (INIS)

    Hendry, J.H.; Wang, S.B.; Testa, N.G.

    1984-01-01

    The Do value fibroblastoid colony-forming units in mouse bone-marrow increased from 1.7 Gy using γ-rays at 4.2 Gy/minute, to 2.6 Gy at 4.5 cGy/minute. In contrast, the sensitivity of bone-marrow stem cells was very little changed (Do approximately 0.9 Gy). At 7.5 Gy acute single dose, the dose sparing achieved for CFU-F using 4.5 cGy/minute was a factor of 1.4, inbetween the values reported for lung of 1.8 and for haemopoiesis of 1.2. Although the role of CFU-F in the haemopoietic environment has not been established, the content of CFU-F can predict the ability of irradiated marrow to sustain haemopoiesis in the long term. Hence the data imply that the haemopoiesis environment, as well as the dose-limiting lung, benefits from the use of low dose-rates for haemopoietic ablations in the treatment of leukaemia. No significant further sparing of CFU-F was achieved using a lower dose-rate of 1.4 cGy per minute

  3. Comparison of the survival (LD/sub 50/30/) of a number of inbred mouse strains after X and /sup 60/Co gamma irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Vacha, J.; Znojil, V.; Hola, J.; Sikulova, J. (Ceskoslovenska Akademie Ved, Brno. Biofysikalni Ustav)

    1984-01-01

    The value of LD/sub 50/30/ for X and /sup 60/Co gamma radiation was ascertained for several inbred mouse strains and the significance of interstrain differences in these parameters determined. The rank order of strains according to LD/sub 50/30/ differs as between the two types of radiation with the exception of the strains BALB/c and B10.LP/Ph, which are the least resistant to radiation-induced lethality with both types of radiation. The strain C57BL/10ScSnPh is highly resistant to X irradiation. The relative biological effectiveness of /sup 60/Co gamma radiation as compared with X-radiation from the point of view of lethality fluctuates between 0.748 and 0.952 in individual strains, with a mean value of 0.866 +- 0.033. The RBE values do not correlate with the radiosensitivity of the strain, but they do correlate with the relative contribution to erythropoiesis of the spleen.

  4. Chimera regimes in a ring of oscillators with local nonlinear interaction

    Science.gov (United States)

    Shepelev, Igor A.; Zakharova, Anna; Vadivasova, Tatiana E.

    2017-03-01

    One of important problems concerning chimera states is the conditions of their existence and stability. Until now, it was assumed that chimeras could arise only in ensembles with nonlocal character of interactions. However, this assumption is not exactly right. In some special cases chimeras can be realized for local type of coupling [1-3]. We propose a simple model of ensemble with local coupling when chimeras are realized. This model is a ring of linear oscillators with the local nonlinear unidirectional interaction. Chimera structures in the ring are found using computer simulations for wide area of values of parameters. Diagram of the regimes on plane of control parameters is plotted and scenario of chimera destruction are studied when the parameters are changed.

  5. Using CHIMERA detector at LNS for gamma-particle coincidences

    Directory of Open Access Journals (Sweden)

    Cardella G.

    2016-01-01

    Full Text Available We have recently evaluated the quality of γ-ray angular distributions that can be extracted in particle-gamma coincidence measurements using the CHIMERA detector at LNS. γ-rays have been detected using the CsI(Tl detectors of the spherical part of the CHIMERA array. Very clean γ-rays angular distributions were extracted in reactions induced by different stable beams impinging on 12C thin targets. The results evidenced an effect of projectile spin flip on the γ-rays angular distributions. γ-particle coincidence measurements were also performed in reactions induced by neutron rich exotic beams produced through in-flight fragmentation at LNS. In recent experiments also the Farcos array was used to improve energy and angular resolution measurements of the detected charged particles. Results obtained with both stable and radioactive beams are reported.

  6. Targeting nanodisks via a single chain variable antibody - Apolipoprotein chimera

    International Nuclear Information System (INIS)

    Iovannisci, David M.; Beckstead, Jennifer A.; Ryan, Robert O.

    2009-01-01

    Nanodisks (ND) are nanometer scale complexes of phospholipid and apolipoprotein that have been shown to function as drug delivery vehicles. ND harboring significant quantities of the antifungal agent, amphotericin B, or the bioactive isoprenoid, all trans retinoic acid, have been generated and characterized. As currently formulated, ND possess limited targeting capability. In this study, we constructed a single chain variable antibody (scFv).apolipoprotein chimera and assessed the ability of this fusion protein to form ND and recognize the antigen to which the scFv is directed. Data obtained revealed that α-vimentin scFv.apolipoprotein A-I is functional in ND formation and antigen recognition, opening the door to the use of such chimeras in targeting drug-enriched ND to specific tissues.

  7. Icing modelling in NSMB with chimera overset grids

    Energy Technology Data Exchange (ETDEWEB)

    Pena, D. [Ècole Polytechnique de Montréal (Canada); ICUBE, Strasbourg University (France); Deloze, T.; Laurendeau, E. [Ècole Polytechnique de Montréal (Canada); Hoarau, Y. [ICUBE, Strasbourg University (France)

    2015-03-10

    In aerospace Engineering, the accurate simulation of ice accretion is a key element to increase flight safety and avoid accidents related to icing effects. The icing code developed in the NSMB solver is based on an Eulerian formulation for droplets tracking, an iterative Messinger model using a modified water runback scheme for ice thickness calculation and mesh deformation to track the ice/air interface through time. The whole process is parallelized with MPI and applied with chimera grids.

  8. The acute effects of alpha and beta irradiation of mouse skin and the factors affecting the response

    International Nuclear Information System (INIS)

    Needham, S.G.; Coggle, J.E.

    1991-01-01

    Several problems regarding acute effects of alpha and beta irradiation were investigated in order to clarify protection problems of localised doses to the skin. A study into the acute biological effects of different energy beta emitters and the effects of energy and area on the response showed direct relationships between these criteria for a range of different acute responses with different time courses. Three different types of acute response were found and these are described as 'moist desquamation', 'acute ulceration' and 'acute epidermal necrosis'. An unexpected finding was that the lower energy beta emitter 170 Tm was as efficient at inducing scab formation as the higher energy 90 Sr sources for the same area of exposure. Experiments using 2x4 cm 2 exposures to 224 Cm alpha particles showed that the response to this poorly penetrating radiation was minimal after doses as high as 180 Gy measured at 10 μm into the skin. In comparison, large area exposure to 170 Tm produced areas of prolonged scabbing after doses up to 100 Gy. However, the intensity of the reaction varied between strains. (author)

  9. Early changes in blood flow of the mouse skin after irradiation as measured by the 133Xe clearance method

    International Nuclear Information System (INIS)

    Tsujii, Hirohiko; Irie, Goro

    1983-01-01

    The early effects of radiation on the local blood flow in the skin of mice were evaluated by measuring the local clearance rate of 133 Xe after its subcutaneous injection; this was done at four to five weeks after irradiation during the animals' normal resting conditions. The fractionation schedules employed were single fractions, two fractions in 15 days and four fractions in 15 days. The dose effect curves with these schedules showed a two-component pattern. There was a uniform reduction in flood flow after 10 to 30 Gy, and a steady increase in flood flow after doses more than 40 Gy. The blood flow after higher-fractionated doses was always lower than less-fractionated doses. It was considered that radiation doses causing higher severity of acute skin reactions might have predominated a degree of acute vasodilatation over fibrotic changes, thus resulting in increased blood flow. A steady increase in early blood flow was observed with increasing severity of acute skin reactions, but the early blood flow was not a good indicator for predicting late skin reactions, except for a severe leg deformity which was accompanied with a significant increase in early blood flow. (author)

  10. Morphologic changes reflecting early and late effects of irradiation of the distal lung of the mouse: a review

    International Nuclear Information System (INIS)

    Penney, D.P.; Siemann, D.W.; Rubin, P.; Shapiro, D.L.; Finkelstein, J.; Cooper, R.A. Jr.

    1982-01-01

    In radiation of the thorax, the lung has been shown to be a major dose-limiting organ. The early and late responses of the lung to radiation has been reviewed, with primary emphasis on the following cell types: type II pneumocyte, type I pneumocyte, pulmonary endothelial cell and macrophage. The earliest observable and quantifiable cellular response to radiation is exhibited by the type II pneumocytes as a decrease in lamellar bodies and a corresponding increase in surfactant content of the alveolar lavage. By 18-63 weeks following exposure, several type II cells, restored in their lamellar body population, undergo degeneration and sloughing into alveolar spaces. Type I pneumocytes generally exhibit little change, although some investigators describe alveolar denudation due to degenerating type I cells. Macrophages decrease in numbers following irradiation, returning to normal populations by 4 weeks. These changes correspond closely to the changes in alveolar lavage phospholipid phosphorus. Descriptions of radiation-induced damage to endothelial cells are variable. However, blebbing and vacuolation appear to be late developing responses, although altered permeability may be earlier in its expression. Radiation pneumonitis and fibrosis are the two major clinical and experimental responses of the lung to radiation following exposures of greater than 12 Gy. The former appears to involve type II cells, macrophages and pulmonary endothelial cells, and for the latter macrophages, fibroblasts, type II pneumocytes and the pulmonary endothelial cells are involved. The two events are not interdependent, and may not necessarily be interrelated

  11. Anticipatory Governance: Bioethical Expertise for Human/Animal Chimeras

    Science.gov (United States)

    Harvey, Alison; Salter, Brian

    2012-01-01

    The governance demands generated by the use of human/animal chimeras in scientific research offer both a challenge and an opportunity for the development of new forms of anticipatory governance through the novel application of bioethical expertise. Anticipatory governance can be seen to have three stages of development whereby bioethical experts move from a reactive to a proactive stance at the edge of what is scientifically possible. In the process, the ethicists move upstream in their engagement with the science of human-to-animal chimeras. To what extent is the anticipatory coestablishment of the principles and operational rules of governance at this early stage in the development of the human-to-animal research field likely to result in a framework for bioethical decision making that is in support of science? The process of anticipatory governance is characterised by the entwining of the scientific and the philosophical so that judgements against science are also found to be philosophically unfounded, and conversely, those activities that are permissible are deemed so on both scientific and ethical grounds. Through what is presented as an organic process, the emerging bioethical framework for human-to-animal chimera research becomes a legitimating framework within which ‘good’ science can safely progress. Science gives bioethical expertise access to new governance territory; bioethical expertise gives science access to political acceptability. PMID:23576848

  12. Multiclustered chimeras in large semiconductor laser arrays with nonlocal interactions

    Science.gov (United States)

    Shena, J.; Hizanidis, J.; Hövel, P.; Tsironis, G. P.

    2017-09-01

    The dynamics of a large array of coupled semiconductor lasers is studied numerically for a nonlocal coupling scheme. Our focus is on chimera states, a self-organized spatiotemporal pattern of coexisting coherence and incoherence. In laser systems, such states have been previously found for global and nearest-neighbor coupling, mainly in small networks. The technological advantage of large arrays has motivated us to study a system of 200 nonlocally coupled lasers with respect to the emerging collective dynamics. Moreover, the nonlocal nature of the coupling allows us to obtain robust chimera states with multiple (in)coherent domains. The crucial parameters are the coupling strength, the coupling phase and the range of the nonlocal interaction. We find that multiclustered chimera states exist in a wide region of the parameter space and we provide quantitative characterization for the obtained spatiotemporal patterns. By proposing two different experimental setups for the realization of the nonlocal coupling scheme, we are confident that our results can be confirmed in the laboratory.

  13. Chimera states and the interplay between initial conditions and non-local coupling

    Science.gov (United States)

    Kalle, Peter; Sawicki, Jakub; Zakharova, Anna; Schöll, Eckehard

    2017-03-01

    Chimera states are complex spatio-temporal patterns that consist of coexisting domains of coherent and incoherent dynamics. We study chimera states in a network of non-locally coupled Stuart-Landau oscillators. We investigate the impact of initial conditions in combination with non-local coupling. Based on an analytical argument, we show how the coupling phase and the coupling strength are linked to the occurrence of chimera states, flipped profiles of the mean phase velocity, and the transition from a phase- to an amplitude-mediated chimera state.

  14. Simple and complex chimera states in a nonlinearly coupled oscillatory medium

    Science.gov (United States)

    Bolotov, Maxim; Smirnov, Lev; Osipov, Grigory; Pikovsky, Arkady

    2018-04-01

    We consider chimera states in a one-dimensional medium of nonlinear nonlocally coupled phase oscillators. In terms of a local coarse-grained complex order parameter, the problem of finding stationary rotating nonhomogeneous solutions reduces to a third-order ordinary differential equation. This allows finding chimera-type and other inhomogeneous states as periodic orbits of this equation. Stability calculations reveal that only some of these states are stable. We demonstrate that an oscillatory instability leads to a breathing chimera, for which the synchronous domain splits into subdomains with different mean frequencies. Further development of instability leads to turbulent chimeras.

  15. Influence of Radioprotectors on Regeneration of the Mucosa of the Small Intestine of the Mouse after X-Irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Maisin, J. R. [Radiobiological Department, Nuclear Energy Study Centre, Mol (Belgium)

    1968-08-15

    Intestinal death occurs in mice from the third to the fifth day after doses of 1 to 10 krad and is preceded by inhibition of cell division, destruction of the crypts, shortening of the villi and denudation of the intestinal epithelium, BALB/c mice, some of which were protected with 2-{beta}-aminoethylisothiourea (AET) or with one of the following mixtures of chemical protectors: AET+ 5-hydroxytryptamine (5-HT), AET + 5-HT + glutathione (GSH), and AET + 5- HT + GSH + cysteine, were irradiated with doses of 1350 or 2000 R of X-rays (300 kV, 20 m A , dose rate 100 R/min). Mitotic activity, abnormal anaphases, size of nuclei, pyknosis and number of nuclei, migration of nuclei along the villi and incorporation of thymidine were investigated. In all experiments, lesions appeared later and were less pronounced in the protected than in the non-protected mice. Furthermore, AET and the associations of radioprotectors appear to protect the crypt cells of the small intestine during all phases of the mitotic cycle. The best results were obtained with a mixture of AET + 5-HT + GSH + cysteine. After such treatment and a dose of 2000 R of X-rays, a delay of 30 days is nevertheless needed to allow complete recovery of the duodenal mucosa. The diminution of incorporation of thymidine and the prolongation of the regeneration time are symptoms of a 'biochemical shock', and the importance of this in the mechanism of action of sulphydryl compounds and of mixtures of protective drugs is discussed. (author)

  16. Sublethal dose of irradiation enhances invasion of malignant glioma cells through p53-MMP 2 pathway in U87MG mouse brain tumor model

    International Nuclear Information System (INIS)

    Pei, Jian; Park, In-Ho; Ryu, Hyang-Hwa; Li, Song-Yuan; Li, Chun-Hao; Lim, Sa-Hoe; Wen, Min; Jang, Woo-Youl; Jung, Shin

    2015-01-01

    Glioblastoma is a highly lethal neoplasm that frequently recurs locally after radiotherapy, and most of these recurrences originate from near the irradiated target field. In the present study, we identified the effects of radiation on glioma invasion and p53, TIMP-2, and MMP-2 expression through in vitro and in vivo experiments. The U87MG (wt p53) and U251 (mt p53) human malignant glioma cell lines were prepared, and the U2OS (wt 53) and Saos2 (del p53) osteosarcoma cell lines were used as p53 positive and negative controls. The four cell lines and p53 knock-downed U87MG cells received radiation (2–6 Gy) and were analyzed for expression of p53 and TIMP-2 by Western blot, and MMP-2 activity was detected by zymography. In addition, the effects of irradiation on directional invasion of malignant glioma were evaluated by implanting nude mice with bioluminescent u87-Fluc in vivo followed by MMP-2, p53, and TIMP-2 immunohisto-chemistry and in situ zymography. MMP-2 activity and p53 expression increased in proportional to the radiation dose in cell lines with wt p53, but not in the cell lines with del or mt p53. TIMP-2 expression did not increase in U87MG cells. MMP-2 activity decreased in p53 knock-downed U87MG cells but increased in the control group. Furthermore, radiation enhanced MMP-2 activity and increased tumor margin invasiveness in vivo. Tumor cells invaded by radiation overexpressed MMP-2 and p53 and revealed high gelatinolytic activity compared with those of non-radiated tumor cells. Radiation-induced upregulation of p53 modulated MMP-2 activity, and the imbalance between MMP-2 and TIMP-2 may have an important role in glioblastoma invasion by degrading the extracellular matrix. Bioluminescent “U87-Fluc”was useful for observing tumor formation without sacrifice after implanting tumor cells in the mouse brain. These findings suggest that the radiotherapy involved field for malignant glioma needs to be reconsidered, and that future trials should investigate

  17. Leptin deficiency-induced obesity exacerbates ultraviolet B radiation-induced cyclooxygenase-2 expression and cell survival signals in ultraviolet B-irradiated mouse skin

    International Nuclear Information System (INIS)

    Sharma, Som D.; Katiyar, Santosh K.

    2010-01-01

    Obesity has been implicated in several inflammatory diseases and in different types of cancer. Chronic inflammation induced by exposure to ultraviolet (UV) radiation has been implicated in various skin diseases, including melanoma and nonmelanoma skin cancers. As the relationship between obesity and susceptibility to UV radiation-caused inflammation is not clearly understood, we assessed the role of obesity on UVB-induced inflammation, and mediators of this inflammatory response, using the genetically obese (leptin-deficient) mouse model. Leptin-deficient obese (ob/ob) mice and wild-type counterparts (C57/BL6 mice) were exposed to UVB radiation (120 mJ/cm 2 ) on alternate days for 1 month. The mice were then euthanized and skin samples collected for analysis of biomarkers of inflammatory responses using immunohistochemistry, western blotting, ELISA and real-time PCR. Here, we report that the levels of inflammatory responses were higher in the UVB-exposed skin of the ob/ob obese mice than those in the UVB-exposed skin of the wild-type non-obese mice. The levels of UVB-induced cyclooxygenase-2 expression, prostaglandin-E 2 production, proinflammatory cytokines (i.e., tumor necrosis factor-α, interleukin-1β, interleukin-6), and proliferating cell nuclear antigen and cell survival signals (phosphatidylinositol-3-kinase and p-Akt-Ser 473 ) were higher in the skin of the ob/ob obese mice than the those in skin of their wild-type non-obese counterparts. Compared with the wild-type non-obese mice, the leptin-deficient obese mice also exhibited greater activation of NF-κB/p65 and fewer apoptotic cells in the UVB-irradiated skin. Our study suggests for the first time that obesity in mice is associated with greater susceptibility to UVB-induced inflammatory responses and, therefore, obesity may increase susceptibility to UVB-induced inflammation-associated skin diseases, including the risk of skin cancer.

  18. Advances in Chimera Grid Tools for Multi-Body Dynamics Simulations and Script Creation

    Science.gov (United States)

    Chan, William M.

    2004-01-01

    This viewgraph presentation contains information about (1) Framework for multi-body dynamics - Geometry Manipulation Protocol (GMP), (2) Simulation procedure using Chimera Grid Tools (CGT) and OVERFLOW-2 (3) Further recent developments in Chimera Grid Tools OVERGRID, Grid modules, Script library and (4) Future work.

  19. STAT3 Gene Silencing by Aptamer-siRNA Chimera as Selective Therapeutic for Glioblastoma

    Directory of Open Access Journals (Sweden)

    Carla Lucia Esposito

    2018-03-01

    Full Text Available Glioblastoma (GBM is the most frequent and aggressive primary brain tumor in adults, and despite advances in neuro-oncology, the prognosis for patients remains dismal. The signal transducer and activator of transcription-3 (STAT3 has been reported as a key regulator of the highly aggressive mesenchymal GBM subtype, and its direct silencing (by RNAi oligonucleotides has revealed a great potential as an anti-cancer therapy. However, clinical use of oligonucleotide-based therapies is dependent on safer ways for tissue-specific targeting and increased membrane penetration. The objective of this study is to explore the use of nucleic acid aptamers as carriers to specifically drive a STAT3 siRNA to GBM cells in a receptor-dependent manner. Using an aptamer that binds to and antagonizes the oncogenic receptor tyrosine kinase PDGFRβ (Gint4.T, here we describe the design of a novel aptamer-siRNA chimera (Gint4.T-STAT3 to target STAT3. We demonstrate the efficient delivery and silencing of STAT3 in PDGFRβ+ GBM cells. Importantly, the conjugate reduces cell viability and migration in vitro and inhibits tumor growth and angiogenesis in vivo in a subcutaneous xenograft mouse model. Our data reveals Gint4.T-STAT3 conjugate as a novel molecule with great translational potential for GBM therapy.

  20. Photodynamic therapy using a novel irradiation source, LED lamp, is similarly effective to photodynamic therapy using diode laser or metal-halide lamp on DMBA- and TPA-induced mouse skin papillomas.

    Science.gov (United States)

    Takahashi, Hidetoshi; Nakajima, Susumu; Ogasawara, Koji; Asano, Ryuji; Nakae, Yoshinori; Sakata, Isao; Iizuka, Hajime

    2014-08-01

    Photodynamic therapy (PDT) is useful for superficial skin tumors such as actinic keratosis and Bowen disease. Although PDT is non-surgical and easily-performed treatment modality, irradiation apparatus is large and expensive. Using 7, 12-dimethylbenz[a]anthracene (DMBA) and 12-ο-tetradecanoylphorbol-13-acetate (TPA)-induced mouse skin papilloma model, we compared the efficacy of TONS501- and ALA-PDT with a LED lamp, a diode laser lamp or a metal-halide lamp on the skin tumor regression. TONS501-PDT using 660 nm LED lamp showed anti-tumor effect at 1 day following the irradiation and the maximal anti-tumor effect was observed at 3 days following the irradiation. There was no significant difference in the anti-tumor effects among TONS501-PDT using LED, TONS501-PDT using diode laser, and 5-aminolevulinic acid hydrochloride (ALA)-PDT using metal-halide lamp. Potent anti-tumor effect on DMBA- and TPA-induced mouse skin papilloma was observed by TONS501-PDT using 660 nm LED, which might be more useful for clinical applications. © 2014 Japanese Dermatological Association.

  1. Chaotic weak chimeras and their persistence in coupled populations of phase oscillators

    International Nuclear Information System (INIS)

    Bick, Christian; Ashwin, Peter

    2016-01-01

    Nontrivial collective behavior may emerge from the interactive dynamics of many oscillatory units. Chimera states are chaotic patterns of spatially localized coherent and incoherent oscillations. The recently-introduced notion of a weak chimera gives a rigorously testable characterization of chimera states for finite-dimensional phase oscillator networks. In this paper we give some persistence results for dynamically invariant sets under perturbations and apply them to coupled populations of phase oscillators with generalized coupling. In contrast to the weak chimeras with nonpositive maximal Lyapunov exponents constructed so far, we show that weak chimeras that are chaotic can exist in the limit of vanishing coupling between coupled populations of phase oscillators. We present numerical evidence that positive Lyapunov exponents can persist for a positive measure set of this inter-population coupling strength. (paper)

  2. Infusion of donor lymphocytes into stable canine radiation chimeras: implications for mechanism of transplantation tolerance

    International Nuclear Information System (INIS)

    Weiden, P.L.; Storb, R.; Tsoi, M.S.; Graham, T.C.; Lerner, K.G.; Thomas, E.D.

    1976-01-01

    Canine radiation chimeras were used to investigate further mechanism(s) responsible for maintaining the stable chimeric state. In an attempt to elucidate the nature of this postulated active mechanism, the cytotoxicity of donor lymphocytes for fibroblasts of the chimera and the presence or absence of serum-blocking factors were assessed in vitro by using a cellular inhibition (CI) assay. The presence of serum-blocking factors did not protect against the development of significant GVHD in two chimeras (fatal in one). GVHD did not occur in four other chimeras after infusion of cytotoxic donor lymphocytes despite the absence of serum-blocking factors. These and previous results suggest that serum-blocking factors are not the mechanism suppressing the development of GVHD in canine radiation chimeras, and raise the possibility that a suppressor cell population may be responsible for preventing GVHD

  3. Experimental observation of chimera and cluster states in a minimal globally coupled network

    Energy Technology Data Exchange (ETDEWEB)

    Hart, Joseph D. [Institute for Research in Electronics and Applied Physics, University of Maryland, College Park, Maryland 20742 (United States); Department of Physics, University of Maryland, College Park, Maryland 20742 (United States); Bansal, Kanika [Department of Mathematics, University at Buffalo, SUNY Buffalo, New York 14260 (United States); US Army Research Laboratory, Aberdeen Proving Ground, Maryland 21005 (United States); Murphy, Thomas E. [Institute for Research in Electronics and Applied Physics, University of Maryland, College Park, Maryland 20742 (United States); Department of Electrical and Computer Engineering, University of Maryland, College Park, Maryland 20742 (United States); Roy, Rajarshi [Institute for Research in Electronics and Applied Physics, University of Maryland, College Park, Maryland 20742 (United States); Department of Physics, University of Maryland, College Park, Maryland 20742 (United States); Institute for Physical Science and Technology, University of Maryland, College Park, Maryland 20742 (United States)

    2016-09-15

    A “chimera state” is a dynamical pattern that occurs in a network of coupled identical oscillators when the symmetry of the oscillator population is broken into synchronous and asynchronous parts. We report the experimental observation of chimera and cluster states in a network of four globally coupled chaotic opto-electronic oscillators. This is the minimal network that can support chimera states, and our study provides new insight into the fundamental mechanisms underlying their formation. We use a unified approach to determine the stability of all the observed partially synchronous patterns, highlighting the close relationship between chimera and cluster states as belonging to the broader phenomenon of partial synchronization. Our approach is general in terms of network size and connectivity. We also find that chimera states often appear in regions of multistability between global, cluster, and desynchronized states.

  4. Interordinal chimera formation between medaka and zebrafish for analyzing stem cell differentiation.

    Science.gov (United States)

    Hong, Ni; Chen, Songlin; Ge, Ruowen; Song, Jianxing; Yi, Meisheng; Hong, Yunhan

    2012-08-10

    Chimera formation is a standard test for pluripotency of stem cells in vivo. Interspecific chimera formation between distantly related organisms offers also an attractive approach for propagating endangered species. Parameters influencing interspecies chimera formation have remained poorly elucidated. Here, we report interordinal chimera formation between medaka and zebrafish, which separated ∼320 million years ago and exhibit a more than 2-fold difference in developmental speed. We show that, on transplantation into zebrafish blastulae, both noncultivated blastomeres and long-term cultivated embryonic stem (ES) cells of medaka adopted the zebrafish developmental program and differentiated into physiologically functional cell types including pigment cells, blood cells, and cardiomyocytes. We also show that medaka ES cells express differentiation gene markers during chimeric embryogenesis. Therefore, the evolutionary distance and different embryogenesis speeds do not produce donor-host incompatibility to compromise chimera formation between medaka and zebrafish, and molecular markers are valuable for analyzing lineage commitment and cell differentiation in interspecific chimeric embryos.

  5. Targeted chimera delivery to ovarian cancer cells by heterogeneous gold magnetic nanoparticle

    Science.gov (United States)

    Chen, Yao; Xu, Mengjiao; Guo, Yi; Tu, Keyao; Wu, Weimin; Wang, Jianjun; Tong, Xiaowen; Wu, Wenjuan; Qi, Lifeng; Shi, Donglu

    2017-01-01

    Efficient delivery of small interfering RNAs (siRNAs) to the targeted cells has remained a significant challenge in clinical applications. In the present study, we developed a novel aptamer-siRNA chimera delivery system mediated by cationic Au-Fe3O4 nanoparticles (NPs). The chimera constructed by VEGF RNA aptamer and Notch3 siRNA was bonded with heterogeneous Au-Fe3O4 nanoparticles by electrostatic interaction. The obtained complex exhibited much higher silencing efficiency against Notch3 gene compared with chimera alone and lipofectamine-siRNA complex, and improved the antitumor effects of the loaded chimera. Moreover, the efficient delivery of the chimera by Au-Fe3O4 NPs could reverse multi-drug resistance (MDR) of ovarian cancer cells against the chemotherapeutic drug cisplatin, indicating its potential capability for future targeted cancer therapy while overcoming MDR.

  6. Periodic synchronization and chimera in conformist and contrarian oscillators

    Science.gov (United States)

    Hong, Hyunsuk

    2014-06-01

    We consider a system of phase oscillators that couple with both attractive and repulsive interaction under a pinning force and explore collective behavior of the system. The oscillators can be divided into two subpopulations of "conformist" oscillators with attractive interaction and "contrarian" ones with repulsive interaction. We find that the interplay between the pinning force and the opposite relationship of the conformist and contrarian oscillators induce peculiar dynamic states: periodic synchronization, breathing chimera, and fully pinned state depending on the fraction of the conformists. Using the Watanabe-Strogatz transformation, we reduce the dynamics into a low-dimensional one and find that the above dynamic states are generated from the reduced dynamics.

  7. Estimation of dependence between mean of fractionation of photons and neutrons dose and intensity of post-irradiation reaction of mouse large intestine; Ocena zaleznosci pomiedzy sposobem frakcjonowania dawki fotonow i neutronow a nasileniem popromiennego odczynu jelita grubego myszy

    Energy Technology Data Exchange (ETDEWEB)

    Gasinska, A. [Oncology Center, Cracow (Poland)

    1995-12-31

    The aim of the work was verification of mouse large intestine tolerance on fractionated 250 kV X-rays and 2.3 MeV neutrons doses. Two cm of large intestine of mouse CBA/HT strain were irradiated with various fraction doses: from 0.25 to 35 Gy of X-rays and 0.05-12 Gy of neutrons. The measure of injury was handicap of intestine function. Early post-irradiation reaction was measured by loss of body weight (2-3 weeks after irradiation) and mouse mortality (till 2 months after irradiation, LD50/2). The late reaction was measured on the base of maximal body weight in 1 year period after irradiation, deformation of excrements (after 10 months) and death of animals (till 12. month after irradiation, LD50/12). Fractionation of X-ray dose influenced on decrease of intensification of late irradiation effects. After fractionation of neutrons this effect has not been observed. {alpha}/{beta} coefficient for X-rays was 19.9 Gy [15.2; 27.0] for body weight nadir, 13.4 Gy [9.3; 19.5] for early mortality (LD50/2), 6.4 Gy [3.6;11.0] for maximal body weight and 6.9 [4.2; 10.8] for late mortality (LD50/12). Analysis of influence of low doses of photons 90.25-4 Gy) and neutrons (0.05-0.8 Gy) showed trend to reduction {alpha}/{beta} for photons only (LD50/2=5.4 Gy; LD50/12=4.6 Gy). {alpha}/{beta} coefficient for neutrons was defined by LQ model only for maximal body weight and was 19.9 Gy [9.5; 61.0]. In application of graphic method {alpha}/{beta} for neutrons was 230 Gy for early and 48 Gy for late effects. Lower values of {alpha}/{beta} coefficient for late irradiation effects for photon radiation demonstrate the big influence of fractionation of photons dose on large intestine tolerance (decrease intensity in all biological effects). Author did not observe increase of intestine tolerance in fractionation of neutrons dose. Effect of irradiation damages repair in interfraction pauses, measured by percent of regenerated dose (F{sub r}) was much bigger for photons. For X-rays it was 50

  8. The SCID-hu mouse and its application to human radiation biology

    International Nuclear Information System (INIS)

    Kyoizumi, Seishi; Akiyama, Mitoshi; McCune, J.M.; Namikawa, Reiko.

    1993-01-01

    The radiobiological study of humans has been hampered by a lack of suitable in vivo experimental models. Of course, acute and chronic radiation effects in humans have been documented in the studies of atomic bomb (A-bomb) survivors and patients irradiated either by therapeutic intent or by accident. However, the information gained from these studies has been limited by the difficulties in estimating precise radiation doses and in obtaining biological samples for directly analyzing the processes of radiation-induced pathogenesis. With these issues in mind, we propose that the severe combined immunodeficient mouse-human chimera can be used as an in vivo experimental model for human radiation biology. We have developed techniques by which normal human bone marrow can be implanted into immunodeficient C.B-17 scid/scid (SCID) mice (S. Kyoizumi et al, Blood 79, 1704, 1992). We have report that this in vivo model can be used for the analysis of radiation damage to human bone marrow. After whole-body irradiation of the engrafted animals, human progenitor cells within the human marrow were destroyed in a dose-dependent manner (D 0 = 0.7-1.0Gy, n = 1.0). Acute hematotoxicity was reduced when the radioprotective agent (WR-2721) was administered prior to irradiation. After low dose irradiation, the recovery of human progenitor activity was accelerated by treatment with human granulocyte-colony stimulating factor (G-CSF). This small animal model may prove amenable for the risk analysis of human radiation exposure as well as for the development of new modalities for the prevention and treatment of radiotoxic damage to the human hematopoietic system. (author)

  9. Curcuma sparganifolia Improvement Through Gamma Irradiation

    International Nuclear Information System (INIS)

    Krasaechai, A.

    1990-01-01

    The studies of Curcuma sparganifolia improvement through irradiation using gamma rays from 40 Gy to inhibit sprouting of the rhizomes were conducted. Various effects of gamma rays on growth and development were observed in 11 parameters. Colour mutation of flowers and braces were not found except in 1 plant which showed deeper brats colour. Leaf chimera was observed but the characters for commercialization were not achieved

  10. Chimera patterns in two-dimensional networks of coupled neurons

    Science.gov (United States)

    Schmidt, Alexander; Kasimatis, Theodoros; Hizanidis, Johanne; Provata, Astero; Hövel, Philipp

    2017-03-01

    We discuss synchronization patterns in networks of FitzHugh-Nagumo and leaky integrate-and-fire oscillators coupled in a two-dimensional toroidal geometry. A common feature between the two models is the presence of fast and slow dynamics, a typical characteristic of neurons. Earlier studies have demonstrated that both models when coupled nonlocally in one-dimensional ring networks produce chimera states for a large range of parameter values. In this study, we give evidence of a plethora of two-dimensional chimera patterns of various shapes, including spots, rings, stripes, and grids, observed in both models, as well as additional patterns found mainly in the FitzHugh-Nagumo system. Both systems exhibit multistability: For the same parameter values, different initial conditions give rise to different dynamical states. Transitions occur between various patterns when the parameters (coupling range, coupling strength, refractory period, and coupling phase) are varied. Many patterns observed in the two models follow similar rules. For example, the diameter of the rings grows linearly with the coupling radius.

  11. Genetic resistance in experimental autoimmune encephalomyelitis. I. Analysis of the mechanism of LeR resistance using radiation chimeras

    International Nuclear Information System (INIS)

    Pelfrey, C.M.; Waxman, F.J.; Whitacre, C.C.

    1989-01-01

    Experimental autoimmune encephalomyelitis (EAE) is a cell-mediated autoimmune disease of the central nervous system that has been extensively studied in the rat. The Lewis rat is highly susceptible to the induction of EAE, while the Lewis resistant (LeR) rat is known to be resistant. In this paper, we demonstrate that the LeR rat, which was derived from the Lewis strain by inbreeding of fully resistant animals, is histocompatible with the Lewis strain. Radiation chimeras, a tool for distinguishing between immunologic and nonimmunologic resistance mechanisms, were utilized to analyze the cellular mechanisms involved in genetic resistance to EAE. By transplanting bone marrow cells from LeR rats into irradiated Lewis recipients, Lewis rats were rendered resistant to EAE induction. Likewise, transplanting Lewis bone marrow cells into irradiated LeR recipients rendered LeR rats susceptible. Mixed lymphoid cell chimeras using bone marrow, spleen, and thymus cells in Lewis recipient rats revealed individual lymphoid cell types and cell interactions that significantly affected the incidence and severity of EAE. Our results suggest that LeR resistance is mediated by hematopoietic/immune cells, and that cells located in the spleen appear to play a critical role in the resistance/susceptibility to EAE induction. Depletion of splenic adherent cells did not change the patterns of EAE resistance. In vivo cell mixing studies suggested the presence of a suppressor cell population in the LeR spleen preparations which exerted an inhibitory effect on Lewis autoimmune responses. Thus, the mechanism of LeR resistance appears to be different from that in other EAE-resistant animals

  12. Chimera states in a Hodgkin-Huxley model of thermally sensitive neurons

    Science.gov (United States)

    Glaze, Tera A.; Lewis, Scott; Bahar, Sonya

    2016-08-01

    Chimera states occur when identically coupled groups of nonlinear oscillators exhibit radically different dynamics, with one group exhibiting synchronized oscillations and the other desynchronized behavior. This dynamical phenomenon has recently been studied in computational models and demonstrated experimentally in mechanical, optical, and chemical systems. The theoretical basis of these states is currently under active investigation. Chimera behavior is of particular relevance in the context of neural synchronization, given the phenomenon of unihemispheric sleep and the recent observation of asymmetric sleep in human patients with sleep apnea. The similarity of neural chimera states to neural "bump" states, which have been suggested as a model for working memory and visual orientation tuning in the cortex, adds to their interest as objects of study. Chimera states have been demonstrated in the FitzHugh-Nagumo model of excitable cells and in the Hindmarsh-Rose neural model. Here, we demonstrate chimera states and chimera-like behaviors in a Hodgkin-Huxley-type model of thermally sensitive neurons both in a system with Abrams-Strogatz (mean field) coupling and in a system with Kuramoto (distance-dependent) coupling. We map the regions of parameter space for which chimera behavior occurs in each of the two coupling schemes.

  13. Effects of T cell depletion in radiation bone marrow chimeras. II. Requirement for allogeneic T cells in the reconstituting bone marrow inoculum for subsequent resistance to breaking of tolerance

    International Nuclear Information System (INIS)

    Sykes, M.; Sheard, M.A.; Sachs, D.H.

    1988-01-01

    The ability of normal recipient-type lymphocytes to break tolerance in long-term allogenic radiation chimeras has been investigated. Reconstitution of lethally irradiated mice with a mixture of syngeneic and allogeneic T cell-depleted (TCD) bone marrow (BM) has previously been shown to lead to mixed chimerism and permanent, specific tolerance to donor and host alloantigen (3-5). If allogeneic T cells are not depleted from the reconstituting inoculum, complete allogeneic chimerism results; however, no clinical evidence for GVHD is observed, presumably due to the protective effect provided by syngeneic TCD BM. This model has now been used to study the effects of allogenic T cells administered in reconstituting BM inocula on stability of long-term tolerance. We have attempted to break tolerance in long-term chimeras originally reconstituted with TCD or non-TCD BM by challenging them with inocula containing normal, nontolerant recipient strain lymphocytes. tolerance was broken with remarkable ease in recipients of mixed marrow inocula in which both original BM components were TCD. In contrast, tolerance in chimeras originally reconstituted with non-TCD allogeneic BM was not affected by such inocula. Susceptibility to loss of chimerism and tolerance was not related to initial levels of chimerism per se, but rather to T cell depletion of allogeneic BM, since chimeras reconstituted with TCD allogeneic BM alone (mean level of allogeneic chimerism 98%) were as susceptible as mixed chimeras to the tolerance-breaking effects of such inocula. The possible contribution of GVH reactivity to this resistance was investigated using an F1 into parent strain combination. In these animals, the use of non-TCD F1 BM inocula for reconstitution did not lead to resistance to the tolerance-breaking effects of recipient strain splenocytes

  14. Chimera Type Behavior in Nonlocal Coupling System with Two Different Inherent Frequencies

    Science.gov (United States)

    Lin, Larry; Li, Ping-Cheng; Tseng, Hseng-Che

    2014-03-01

    From the research of Kuramoto and Strogatz, arrays of identical oscillators can display a remarkable pattern, named chimera state, in which phase-locked oscillators coexist with drifting ones in nonlocal coupling oscillator system. We consider further in this study, two groups of oscillators with different inherent frequencies and arrange them in a ring. When the difference of the inherent frequencies is within some specific parameter range, oscillators of nonlocal coupling system show two distinct chimera states. When the parameter value exceeds some threshold value, two chimera states disappear. They show different features. The statistical dynamic behavior of the system can be described by Kuramoto theory.

  15. Chimeras in a network of three oscillator populations with varying network topology

    DEFF Research Database (Denmark)

    Martens, Erik Andreas

    2010-01-01

    this system as a model system, we discuss for the first time the influence of network topology on the existence of so-called chimera states. In this context, the network with three populations represents an interesting case because the populations may either be connected as a triangle, or as a chain, thereby......-like. By showing that chimera states only exist for a bounded set of parameter values, we demonstrate that their existence depends strongly on the underlying network structures, and conclude that chimeras exist on networks with a chain-like character....

  16. Robust Weak Chimeras in Oscillator Networks with Delayed Linear and Quadratic Interactions

    Science.gov (United States)

    Bick, Christian; Sebek, Michael; Kiss, István Z.

    2017-10-01

    We present an approach to generate chimera dynamics (localized frequency synchrony) in oscillator networks with two populations of (at least) two elements using a general method based on a delayed interaction with linear and quadratic terms. The coupling design yields robust chimeras through a phase-model-based design of the delay and the ratio of linear and quadratic components of the interactions. We demonstrate the method in the Brusselator model and experiments with electrochemical oscillators. The technique opens the way to directly bridge chimera dynamics in phase models and real-world oscillator networks.

  17. Chimera states in complex networks: interplay of fractal topology and delay

    Science.gov (United States)

    Sawicki, Jakub; Omelchenko, Iryna; Zakharova, Anna; Schöll, Eckehard

    2017-06-01

    Chimera states are an example of intriguing partial synchronization patterns emerging in networks of identical oscillators. They consist of spatially coexisting domains of coherent (synchronized) and incoherent (desynchronized) dynamics. We analyze chimera states in networks of Van der Pol oscillators with hierarchical connectivities, and elaborate the role of time delay introduced in the coupling term. In the parameter plane of coupling strength and delay time we find tongue-like regions of existence of chimera states alternating with regions of existence of coherent travelling waves. We demonstrate that by varying the time delay one can deliberately stabilize desired spatio-temporal patterns in the system.

  18. Immune responsiveness and incidence of reticulum cell sarcoma in long-term syngeneic radiation chimeras

    International Nuclear Information System (INIS)

    Adorini, L.; Gorini, G.; Covelli, V.; Ballardin, E.; di Michele, A.; Bassani, B.; Metalli, P.; Doria, G.

    1976-01-01

    Long-term syngeneic radiation chimeras displayed a very low incidence of reticulum cell sarcoma as compared with control mice. Immune reactivity of these animals was studied in vivo by anti-dinitrophenyl antibody titer and affinity and in vitro by mitotic responsiveness to phytohemagglutinin, concanavalin A and lipopolysaccharide. Antibody titer and affinity as well as the response to T lectins were found to be increased in chimeras. These results were attributed to increased function of mature T2 cells, which could explain the reduced incidence of reticulum cell sarcoma in chimeras

  19. Mechanisms of appearance of amplitude and phase chimera states in ensembles of nonlocally coupled chaotic systems

    Science.gov (United States)

    Bogomolov, Sergey A.; Slepnev, Andrei V.; Strelkova, Galina I.; Schöll, Eckehard; Anishchenko, Vadim S.

    2017-02-01

    We explore the bifurcation transition from coherence to incoherence in ensembles of nonlocally coupled chaotic systems. It is firstly shown that two types of chimera states, namely, amplitude and phase, can be found in a network of coupled logistic maps, while only amplitude chimera states can be observed in a ring of continuous-time chaotic systems. We reveal a bifurcation mechanism by analyzing the evolution of space-time profiles and the coupling function with varying coupling coefficient and formulate the necessary and sufficient conditions for realizing the chimera states in the ensembles.

  20. Construction and characterization of the interdomain chimeras using Cry11Aa and Cry11Ba from Bacillus thuringiensis and identification of a possible novel toxic chimera.

    Science.gov (United States)

    Sun, Yunjun; Zhao, Qiang; Zheng, Dasheng; Ding, Xuezhi; Wang, Jingfang; Hu, Quanfang; Yuan, Zhiming; Park, Hyun-Woo; Xia, Liqiu

    2014-01-01

    Three structural domains of mosquitocidal Cry11Aa and Cry11Ba from Bacillus thuringiensis were exchanged to produce interdomain chimeras [BAA (11Ba/11Aa/11Aa), ABA (11Aa/11Ba/11Aa), AAB (11Aa/11Aa/11Ba), ABB (11Aa/11Ba/11Ba), BAB (11Ba/11Aa/11Ba), BBA (11Ba/11Ba/11Aa]. Chimeras BAB, BAA, BBA, and AAB formed inclusion bodies in the crystal-negative B. thuringiensis host and produced expected protein bands on SDS-PAGE gel. However, no inclusion body or target protein could be found for chimeras ABA and ABB. In bioassays using the fourth-instar larvae of Culex quinquefasciatus and Aedes aegypti, AAB had ~50 % lethal concentrations of 4.8 and 2.2 μg ml(-1), respectively; however, the rest of chimeras were not toxic. This study thus helps to understand the domain-function relationships of the Cry11Aa and Cry11Ba toxins. The toxic chimera, AAB, might be a candidate for mosquito control as its amino acid sequence is different from the two parental toxins.

  1. On applications of chimera grid schemes to store separation

    Science.gov (United States)

    Cougherty, F. C.; Benek, J. A.; Steger, J. L.

    1985-01-01

    A finite difference scheme which uses multiple overset meshes to simulate the aerodynamics of aircraft/store interaction and store separation is described. In this chimera, or multiple mesh, scheme, a complex configuration is mapped using a major grid about the main component of the configuration, and minor overset meshes are used to map each additional component such as a store. As a first step in modeling the aerodynamics of store separation, two dimensional inviscid flow calculations were carried out in which one of the minor meshes is allowed to move with respect to the major grid. Solutions of calibrated two dimensional problems indicate that allowing one mesh to move with respect to another does not adversely affect the time accuracy of an unsteady solution. Steady, inviscid three dimensional computations demonstrate the capability to simulate complex configurations, including closely packed multiple bodies.

  2. Amplitude mediated chimera states with active and inactive oscillators

    Science.gov (United States)

    Mukherjee, Rupak; Sen, Abhijit

    2018-05-01

    The emergence and nature of amplitude mediated chimera states, spatio-temporal patterns of co-existing coherent and incoherent regions, are investigated for a globally coupled system of active and inactive Ginzburg-Landau oscillators. The existence domain of such states is found to shrink and shift in parametric space with the increase in the fraction of inactive oscillators. The role of inactive oscillators is found to be twofold—they get activated to form a separate region of coherent oscillations and, in addition, decrease the common collective frequency of the coherent regions by their presence. The dynamical origin of these effects is delineated through a bifurcation analysis of a reduced model system that is based on a mean field approximation. Our results may have practical implications for the robustness of such states in biological or physical systems where age related deterioration in the functionality of components can occur.

  3. Present status of the Chimera-Isospin experiment

    International Nuclear Information System (INIS)

    Politi, G.; Arena, N.; Cardella, G.; DeFilippo, E.; Lanzano, G.; Nigro, S.L.; Pagano, A.; Papa, M.; Pirrone, S.; Russotto, P.; Alderighi, M.; Sechi, G.; Sperduto, M.L.; Amorini, F.; Anzalone, A.; Baran, V.; Bonasera, A.; Cavallaro, S.L.; Colonna, M.; Di Toro, M.; LaGuidara, E.; Lanzalone, G.; IaconoManno, M.; Giustolisi, F.; Maiolino, C.; Porto, F.; Rizzo, F.; Trifiro, A.; Trimarchi, M.; Auditore, L.; Barna, R.; DePasquale, D.; Berceanu, I.; Petrovici, M.; Pop, A.; Blicharska, J.; Grzeszczuk, A.; Kowalski, S.; Zipper, W.; Borderie, B.; LeNeindre, N.; Rivet, M.F.; Bougault, R.; Briczycnski, J.; Gawlikowicz, W.; Majka, Z.; Planeta, R.; Bruno, M.; D'Agostino, M.; Fuschini, E.; Geraci, E.; Vannini, G.; Chatterjee, M.B.; Chbihi, A.; Wieleczko, J.P.; Cibor, J.; Dayras, R.; Guazzoni, P.; Russo, S.; Sassi, M.; Zetta, L.; Guinet, D.; Li, S.; Wu, H.; Xiao, Z.; Nicolis, N.G.; Piasecki, E.; Swiderski, L.; Rosato, E.; Vigilante, M.; Wilczynski, J.; Siwek-Wilczynska, K.; Skwira, I.

    2003-01-01

    The CHIMERA detector was designed to significantly contribute to multifragmentation studies in the field of heavy ion collisions at intermediate energies. The device has been used at 'Laboratori Nazionali del Sud' (LNS) in Catania (Italy) to study different aspects of the relevant nuclear reaction mechanism, in two different campaigns: the first one in 2000, by using the forward part (1 - 30 degrees) of the device, and the second one in 2003, by using the 4π geometry. The experimental results have confirmed the capability of the apparatus for good isotopic identification of light charged particles and light fragments (3< Z<10) in a wide angular detection range. The data analysis relative to the first 2000 campaign (REVERSE) is presently aimed to disentangle dynamical and equilibrium emission components in multifragmentation reactions and to learn more about the role of the isospin degree of freedom in asymmetric nuclear matter. Reduction of the data of the second campaign is still in progress. (authors)

  4. In vitro neoformation of grape chimeras (Vitis vinifera L.

    Directory of Open Access Journals (Sweden)

    Sandrine Verdisson

    1999-03-01

    Full Text Available Difference in grape sensitivity to Botrytis cinerea attacks between cultivars was explained by differences in the epidermic tissue of the fruit. Therefore, this work was conducted to create a grape periclinal chimera, whose fruits would combine the skin of a Botrytis tolerant cultivar with a pulp of an another cultivar admitted its good organoleptic quality and productivity. In a first time, graftings of two cultivars (Chardonnay and Pinot noir were conducted in vitro on 5 different media supplemented with various plant growth regulators. Adventitious shoots were only observed on medium containing BAP and GA3 from a mixed callus structure after four weeks of darkness followed by a light/dark regime. In a second time, RAPD analysis, conducted on these plants, showed their chimerical characteristics.

  5. Bovine and human lactoferricin peptides: chimeras and new cyclic analogs.

    Science.gov (United States)

    Arias, Mauricio; McDonald, Lindsey J; Haney, Evan F; Nazmi, Kamran; Bolscher, Jan G M; Vogel, Hans J

    2014-10-01

    Lactoferrin (LF) is an important antimicrobial and immune regulatory protein present in neutrophils and most exocrine secretions of mammals. The antimicrobial activity of LF has been related to the presence of an antimicrobial peptide sequence, called lactoferricin (LFcin), located in the N-terminal region of the protein. The antimicrobial activity of bovine LFcin is considerably stronger than the human version. In this work, chimera peptides combining segments of bovine and human LFcin were generated in order to study their antimicrobial activity and mechanism of action. In addition, the relevance of the conserved disulfide bridge and the resulting cyclic structure of both LFcins were analyzed by using "click chemistry" and sortase A-catalyzed cyclization of the peptides. The N-terminal region of bovine LFcin (residues 17-25 of bovine LF) proved to be very important for the antimicrobial activity of the chimera peptides against E. coli, when combined with the C-terminal region of human LFcin. Similarly the cyclic bovine LFcin analogs generated by "click chemistry" and sortase A preserved the antimicrobial activity of the original peptide, showing the significance of these two techniques in the design of cyclic antimicrobial peptides. The mechanism of action of bovine LFcin and its active derived peptides was strongly correlated with membrane leakage in E. coli and up to some extent with the ability to induce vesicle aggregation. This mechanism was also preserved under conditions of high ionic strength (150 mM NaCl) illustrating the importance of these peptides in a more physiologically relevant system.

  6. Studies on the mechanism of stable graft--host tolerance in canine and human radiation chimeras

    International Nuclear Information System (INIS)

    Storb, R.; Tsoi, M.S.; Weiden, P.L.; Graham, T.C.; Thomas, E.D.

    1976-01-01

    In studies with dogs, marrow donors were immunized against their chimeras by repeated skin grafts which they rejected. Lymphocytes from chimeras and donors were tested for cell inhibition by exposure to skin fibroblasts from chimeras and donors. Results were not compatible with the concept that tolerance in radiation chimeras is maintained by serum-blocking factors. They provide circumstantial evidence against the possibility that the stable chimeric state is the result of the deletion of a close or inactivation of donor lymphocytes specifically responsive for host antigens. They are most consistent with the possibility that a suppressor-cell population is responsible for the maintenance of tolerance. Human recipients of marrow transplants were tested with the cell inhibition assay. Although the incidence of positive cell inhibition and blocking was somewhat higher than in the dog, results were not compatible with the concept that serum blocking is the sole mechanism for maintaining the stable chimeric state in human patients

  7. Status of T- and B-cell cooperation in radiation chimeras: evidence for a suppressor effect

    International Nuclear Information System (INIS)

    Gengozian, N.; Urso, P.

    1976-01-01

    Absolute tolerance may not be in operation in the allogeneic bone marrow chimera, but rather a dynamic state involving interaction not only between the donor and host but also among the donor-lymphoid cells themselves may exist. Whether this observation made in one allogeneic chimera, CD2F 1 → C3BF 1 , will be true for other chimeras (different strain combinations, species) remains to be shown. Thus, the tempo, mode, and requirement for the generation of suppressor T cells are factors that may vary for any specific allogeneic bone marrow transplant. Finally, the manner and degree to which the tolerance-inducing mechanism may affect T- and B-cell functions of the chimera with respect to third-party antigens are yet to be determined

  8. Integration of the GET electronics for the CHIMERA and FARCOS devices

    Science.gov (United States)

    De Filippo, E.; Acosta, L.; Auditore, L.; Boiano, C.; Cardella, G.; Castoldi, A.; D’Andrea, M.; De Luca, S.; Favela, F.; Fichera, F.; Giudice, N.; Gnoffo, B.; Grimaldi, A.; Guazzoni, C.; Lanzalone, G.; Librizzi, F.; Litrico, P.; Maiolino, C.; Maffesanti, S.; Martorana, NS; Pagano, A.; Pagano, EV; Papa, M.; Parsani, T.; Passaro, G.; Pirrone, S.; Politi, G.; Previdi, F.; Quattrocchi, L.; Rizzo, F.; Russotto, P.; Saccà, G.; Salemi, G.; Sciliberto, D.; Trifirò, A.; Trimarchi, M.

    2018-05-01

    A new front-end based on digital GET electronics has been adopted for the readout of the CsI(Tl) detectors of the CHIMERA 4π multi-detector and for the new modular Femtoscopy Array for Correlation and Spectroscopy (FARCOS). It is expected that the coupling of CHIMERA with the FARCOS array, featuring high angular and energy resolution, and the adoption of the new digital electronics will be well suited for improving specific future data analysis, with the full shape storage of the signals, in the field of heavy ion reactions with stable and exotic beams around the Fermi energies domain. Integration of the GET electronics with CHIMERA and FARCOS devices and with the local analog data acquisition will be briefly discussed. We present some results from previous experimental tests and from the first in-beam experiment (Hoyle-Gamma) with the coupled GET+CHIMERA data acquisition.

  9. Application of a Chimera Full Potential Algorithm for Solving Aerodynamic Problems

    Science.gov (United States)

    Holst, Terry L.; Kwak, Dochan (Technical Monitor)

    1997-01-01

    A numerical scheme utilizing a chimera zonal grid approach for solving the three dimensional full potential equation is described. Special emphasis is placed on describing the spatial differencing algorithm around the chimera interface. Results from two spatial discretization variations are presented; one using a hybrid first-order/second-order-accurate scheme and the second using a fully second-order-accurate scheme. The presentation is highlighted with a number of transonic wing flow field computations.

  10. Chimera states in two-dimensional networks of locally coupled oscillators

    Science.gov (United States)

    Kundu, Srilena; Majhi, Soumen; Bera, Bidesh K.; Ghosh, Dibakar; Lakshmanan, M.

    2018-02-01

    Chimera state is defined as a mixed type of collective state in which synchronized and desynchronized subpopulations of a network of coupled oscillators coexist and the appearance of such anomalous behavior has strong connection to diverse neuronal developments. Most of the previous studies on chimera states are not extensively done in two-dimensional ensembles of coupled oscillators by taking neuronal systems with nonlinear coupling function into account while such ensembles of oscillators are more realistic from a neurobiological point of view. In this paper, we report the emergence and existence of chimera states by considering locally coupled two-dimensional networks of identical oscillators where each node is interacting through nonlinear coupling function. This is in contrast with the existence of chimera states in two-dimensional nonlocally coupled oscillators with rectangular kernel in the coupling function. We find that the presence of nonlinearity in the coupling function plays a key role to produce chimera states in two-dimensional locally coupled oscillators. We analytically verify explicitly in the case of a network of coupled Stuart-Landau oscillators in two dimensions that the obtained results using Ott-Antonsen approach and our analytical finding very well matches with the numerical results. Next, we consider another type of important nonlinear coupling function which exists in neuronal systems, namely chemical synaptic function, through which the nearest-neighbor (locally coupled) neurons interact with each other. It is shown that such synaptic interacting function promotes the emergence of chimera states in two-dimensional lattices of locally coupled neuronal oscillators. In numerical simulations, we consider two paradigmatic neuronal oscillators, namely Hindmarsh-Rose neuron model and Rulkov map for each node which exhibit bursting dynamics. By associating various spatiotemporal behaviors and snapshots at particular times, we study the chimera

  11. Chimera states in an ensemble of linearly locally coupled bistable oscillators

    Science.gov (United States)

    Shchapin, D. S.; Dmitrichev, A. S.; Nekorkin, V. I.

    2017-11-01

    Chimera states in a system with linear local connections have been studied. The system is a ring ensemble of analog bistable self-excited oscillators with a resistive coupling. It has been shown that the existence of chimera states is not due to the nonidentity of oscillators and noise, which is always present in real experiments, but is due to the nonlinear dynamics of the system on invariant tori with various dimensions.

  12. Temporal intermittency and the lifetime of chimera states in ensembles of nonlocally coupled chaotic oscillators

    Science.gov (United States)

    Semenova, N. I.; Strelkova, G. I.; Anishchenko, V. S.; Zakharova, A.

    2017-06-01

    We describe numerical results for the dynamics of networks of nonlocally coupled chaotic maps. Switchings in time between amplitude and phase chimera states have been first established and studied. It has been shown that in autonomous ensembles, a nonstationary regime of switchings has a finite lifetime and represents a transient process towards a stationary regime of phase chimera. The lifetime of the nonstationary switching regime can be increased to infinity by applying short-term noise perturbations.

  13. Greengenes: Chimera-checked 16S rRNA gene database and workbenchcompatible in ARB

    Energy Technology Data Exchange (ETDEWEB)

    DeSantis, T.Z.; Hugenholtz, P.; Larsen, N.; Rojas, M.; Brodie,E.L; Keller, K.; Huber, T.; Dalevi, D.; Hu, P.; Andersen, G.L.

    2006-02-01

    A 16S rRNA gene database (http://greengenes.lbl.gov) addresses limitations of public repositories by providing chimera-screening, standard alignments and taxonomic classification using multiple published taxonomies. It was revealed that incongruent taxonomic nomenclature exists among curators even at the phylum-level. Putative chimeras were identified in 3% of environmental sequences and 0.2% of records derived from isolates. Environmental sequences were classified into 100 phylum-level lineages within the Archaea and Bacteria.

  14. Cell surface appearance of unexpected host MHC determinants on thymocytes from radiation bone marrow chimeras

    International Nuclear Information System (INIS)

    Sharrow, S.O.; Mathieson, B.J.; Singer, A.

    1981-01-01

    The phenotypic appearance of cell surface antigens on murine thymocytes from long-term radiation bone marrow chimeras was analyzed using indirect immunofluorescence and flow microfluorometry. Cells maturing in the thymi of these mice were typed for MHC (Kk, I-Ak, H-2b, Kb, and Ib) and non-MHC (Lty 1, Ly 9, and TL) determinants. All cells were of donor origin as determined by non-MHC (Ly) phenotype in P1 leads to P2, P1 x P2 leads to P1, and P1 leads to P2 radiation chimeras. In contrast, the MHC phenotypes of these thymocytes were markedly affected by the host environment. Specifically, H-2 and I-A determinants of both parental phenotypes were detected on thymocytes from P1 leads to P1 x P2 chimeras; I-A determinants of host phenotype were present, whereas I-A determinants of donor phenotype were reduced on thymocytes from P1 x P2 leads to P1 chimeras; and thymocytes from P1 leads to P2 chimeras possessed H-2 and I-A determinants of host phenotype but showed reduction of donor I-A phenotype determinants. The appearance of host cell surface H-2 and I-A determinants on thymocytes from chimeras closely parallels the functional recognition of MHC determinants by T cells from chimeric mice and thus may be significantly related to the development of the self-recognition repertoire by maturing T cells

  15. Spiral wave chimera states in large populations of coupled chemical oscillators

    Science.gov (United States)

    Totz, Jan Frederik; Rode, Julian; Tinsley, Mark R.; Showalter, Kenneth; Engel, Harald

    2018-03-01

    The coexistence of coherent and incoherent dynamics in a population of identically coupled oscillators is known as a chimera state1,2. Discovered in 20023, this counterintuitive dynamical behaviour has inspired extensive theoretical and experimental activity4-15. The spiral wave chimera is a particularly remarkable chimera state, in which an ordered spiral wave rotates around a core consisting of asynchronous oscillators. Spiral wave chimeras were theoretically predicted in 200416 and numerically studied in a variety of systems17-23. Here, we report their experimental verification using large populations of nonlocally coupled Belousov-Zhabotinsky chemical oscillators10,18 in a two-dimensional array. We characterize previously unreported spatiotemporal dynamics, including erratic motion of the asynchronous spiral core, growth and splitting of the cores, as well as the transition from the chimera state to disordered behaviour. Spiral wave chimeras are likely to occur in other systems with long-range interactions, such as cortical tissues24, cilia carpets25, SQUID metamaterials26 and arrays of optomechanical oscillators9.

  16. Development of teeth in chick embryos after mouse neural crest transplantations.

    Science.gov (United States)

    Mitsiadis, Thimios A; Chéraud, Yvonnick; Sharpe, Paul; Fontaine-Pérus, Josiane

    2003-05-27

    Teeth were lost in birds 70-80 million years ago. Current thinking holds that it is the avian cranial neural crest-derived mesenchyme that has lost odontogenic capacity, whereas the oral epithelium retains the signaling properties required to induce odontogenesis. To investigate the odontogenic capacity of ectomesenchyme, we have used neural tube transplantations from mice to chick embryos to replace the chick neural crest cell populations with mouse neural crest cells. The mouse/chick chimeras obtained show evidence of tooth formation showing that avian oral epithelium is able to induce a nonavian developmental program in mouse neural crest-derived mesenchymal cells.

  17. Generation of anti-idiotype scFv for pharmacokinetic measurement in lymphoma patients treated with chimera anti-CD22 antibody SM03.

    Directory of Open Access Journals (Sweden)

    Qi Zhao

    Full Text Available Pre-clinical and clinical studies of therapeutic antibodies require highly specific reagents to examine their immune responses, bio-distributions, immunogenicity, and pharmacodynamics in patients. Selective antigen-mimicking anti-idiotype antibody facilitates the assessment of therapeutic antibody in the detection, quantitation and characterization of antibody immune responses. Using mouse specific degenerate primer pairs and splenocytic RNA, we generated an idiotype antibody-immunized phage-displayed scFv library in which an anti-idiotype antibody against the therapeutic chimera anti-CD22 antibody SM03 was isolated. The anti-idiotype scFv recognized the idiotype of anti-CD22 antibody and inhibited binding of SM03 to CD22 on Raji cell surface. The anti-idiotype scFv was subsequently classified as Ab2γ type. Moreover, our results also demonstrated firstly that the anti-idiotype scFv could be used for pharmacokinetic measurement of circulating residual antibody in lymphoma patients treated with chimera anti-CD22 monoclonal antibody SM03. Of important, the present approach could be easily adopted to generate anti-idiotype antibodies for therapeutic antibodies targeting membrane proteins, saving the cost and time for producing a soluble antigen.

  18. Complement factor 5a receptor chimeras reveal the importance of lipid-facing residues in transport competence

    DEFF Research Database (Denmark)

    Klco, Jeffery M; Sen, Saurabh; Hansen, Jakob L

    2009-01-01

    . Despite relatively conservative substitutions, the lipid-facing chimeras (TM1, TM2, TM4, TM5, TM6 or TM7) were retained in the endoplasmic reticulum/cis-Golgi network. With the exception of the TM7 chimera that did not bind ligand, the lipid-facing chimeras bound ligand with low affinity, but similar...... oligomerization studies demonstrated energy transfer between the wild-type complement factor 5a receptor and the lipid-facing chimeras, suggesting that the lipid-facing residues within a single TM segment are not essential for oligomerization. These studies highlight the importance of the lipid-facing residues...

  19. Four-cluster chimera state in non-locally coupled phase oscillator systems with an external potential

    International Nuclear Information System (INIS)

    Zhu Yun; Zheng Zhi-Gang; Yang Jun-Zhong

    2013-01-01

    Dynamics of a one-dimensional array of non-locally coupled Kuramoto phase oscillators with an external potential is studied. A four-cluster chimera state is observed for the moderate strength of the external potential. Different from the clustered chimera states studied before, the instantaneous frequencies of the oscillators in a synchronized cluster are different in the presence of the external potential. As the strength of the external potential increases, a bifurcation from the two-cluster chimera state to the four-cluster chimera states can be found. These phenomena are well predicted analytically with the help of the Ott—Antonsen ansatz. (general)

  20. Recovery of the proliferative and functional integrity of mouse bone marrow in long-term cultures established after whole-body irradiation at different doses and dose rates

    International Nuclear Information System (INIS)

    Bierkens, J.G.; Hendry, J.H.; Testa, N.G.

    1991-01-01

    Injury inflicted upon the bone marrow stroma following whole-body irradiation and its repair over a 1-year period has been assessed in murine long-term bone marrow cultures established at increasing time intervals after irradiation. Different doses at different dose rates (10 Gy at 0.05 cGy/min, 4.5 Gy and 10 Gy at 1.6 cGy/min, and 4 x 4.5 Gy [3 weeks between doses] at 60 cGy/min) were chosen so as to maximize differences in effect in the stroma. The cellularity of the adherent layer in long-term cultures established 1 month after irradiation was reduced by 40%-90% depending on the dose and dose rate. Simultaneous with the poor ability of the marrow to form adherent layers, the cumulative spleen colony-forming unit (CFU-S) and granulocyte-macrophage colony-forming cell (GM-CFC) production over a 7-week period was reduced to 0% and 30% of control cultures, respectively. The slow recovery of the adherent layer was paralleled by an increase in the numbers of CFU-S and GM-CFC in the supernatant. Cultures established from repeatedly irradiated mice performed poorly over the entire 1-year period. Whereas the regeneration of the stroma was near complete 1 year after irradiation, the CFU-S and GM-CFC levels reached only between 50% and 80% of control cultures, respectively. Also, the concentration of CFU-S and GM-CFC in the supernatant remained persistently lower in cultures established from irradiated mice as compared to control cultures. The levels of sulfated glycosaminoglycans, which have been implicated in the establishment of the functional integrity of the microenvironment, were not reduced in the adherent layers at any time after irradiation. These results indicate that the regeneration of the stroma is accompanied by an incomplete recovery of active hemopoiesis in vitro

  1. Germline competence of mouse ES and iPS cell lines: Chimera technologies and genetic background

    OpenAIRE

    Carstea, Ana Claudia; Pirity, Melinda K; Dinnyes, Andras

    2009-01-01

    In mice, gene targeting by homologous recombination continues to play an essential role in the understanding of functional genomics. This strategy allows precise location of the site of transgene integration and is most commonly used to ablate gene expression (“knock-out”), or to introduce mutant or modified alleles at the locus of interest (“knock-in”). The efficacy of producing live, transgenic mice challenges our understanding of this complex process, and of the factors which influence ger...

  2. Quantitative studies of the fate of epidermal Langerhans cells after X-irradiation of guinea-pig and mouse footpad skin

    Energy Technology Data Exchange (ETDEWEB)

    Cole, S.; Fairweather, J.M.; Townsend, K.M.S.

    1987-01-01

    Langerhans cell numbers, morphology and distribution were observed in cross sections of footpad epidermis from 1 to 28 days after exposure of the hind feed of CBA/H mice or albino guinea-pigs to a single absorbed dose of 20 Gy of X-rays. In mice, the number of Langerhans cells reactive with anti-macrophage F4/80 monoclonal antibody steadily declined by approximately 85% within 10 days after irradiation. Remaining Langerhans cells were exceptionally dendritic. Very few Birbeck granule-containing cells were found in murine popliteal lymph nodes before or after irradiation but damaged cells were present in superficial strata of irradiated epidermis. The morphology and number of epidermal F4/80-positive cells approached normal by 15 days after irradiation. In guinea-pigs, gradual suprabasal movement and loss of rounded, ATPase-positive Langerhans cells from the epidermis were detectable from 5 to 20 days after irradiation but the magnitude of the cell loss and redistribution was partially obscured by the simultaneous appearance of clusters of replacement Langerhans cells in the basal layer and by keratinocyte hyperplasia.

  3. Dose-incidence relationships for exencephalia, anophthalmia and prenatal mortality in mouse embryos irradiated with fission neutrons or 250 kV X-rays

    Energy Technology Data Exchange (ETDEWEB)

    Friedberg, W.; Faulkner, D.N.; Neas, B.R.; Hanneman, G.D.; Darden, E.B. Jr.; Deal, R.B. Jr.; Parker, D.E.

    1987-08-01

    Groups of pregnant mice were irradiated at selected times between 10.00 hours on gestation day 7 and 16.00 hours on day 8. Each group received 0.39 Gy of neutrons or 1.60 Gy of X-rays, or was sham irradiated. We identified a period of high susceptibility of the embryos to radiation-induced exencephalia, anophthalmia and prenatal mortality early in gestation day 8. Dose-incidence relationships in this period were investigated with 0.19-0.48 Gy of neutrons and with 0.40-2.00 Gy of X-rays.

  4. Dose-incidence relationships for exencephalia, anophthalmia and prenatal mortality in mouse embryos irradiated with fission neutrons or 250 kV X-rays

    International Nuclear Information System (INIS)

    Friedberg, W.; Faulkner, D.N.; Neas, B.R.; Hanneman, G.D.; Deal, R.B. Jr.; Parker, D.E.

    1987-01-01

    Groups of pregnant mice were irradiated at selected times between 10.00 hours on gestation day 7 and 16.00 hours on day 8. Each group received 0.39 Gy of neutrons or 1.60 Gy of X-rays, or was sham irradiated. We identified a period of high susceptibility of the embryos to radiation-induced exencephalia, anophthalmia and prenatal mortality early in gestation day 8. Dose-incidence relationships in this period were investigated with 0.19-0.48 Gy of neutrons and with 0.40-2.00 Gy of X-rays. (author)

  5. Cellular basis of the immunohematologic defects observed in short-term semiallogeneic B6C3F1→C3H chimeras: evidence for host-versus-graft reaction initiated by radioresistant T cells

    International Nuclear Information System (INIS)

    Aizawa, S.; Sado, T.; Kamisaku, H.; Kubo, E.

    1980-01-01

    Lethally irradiated C3Hf mice reconstituted with a relatively low dose (2 x 10 6 ) of B6C3F 1 bone marrow cells (B6C3F 1 →C3Hf chimeras) frequently manifest immunohematologic deficiencies during the first month following injection of bone marrow cells. They show slow recovery of antibody-forming potential to sheep red blood cells (SRBC) as compared to that observed in syngeneic (C3Hf→C3Hf or B6C3F 1 →B6C3F 1 ) chimeras. They also show a deficiency of B-cell activity as assessed by antibody response to SRBC following further reconstitution with B6C3F 1 -derived thymus cells 1 week after injection of bone marrow cells. A significant fraction of B6C3F 1 →C3Hf chimeras was shown to manifest a sudden loss of cellularity of spleens during the second week following injection of bone marrow cells even though cellularity was restored to the normal level within 1 week. The splenic mononuclear cells recovered from such chimeras almost invariably showed strong cytotoxicity against target cells expressing donor-type specific H-2 antigens (H-2/sup b/) when assesed by 51 Cr-release assay in vitro. The effector cells responsible for the observed anti-donor specific cytotoxicity were shown to be residual host-derived T cells. These results indicate strongly that residual host T cells could develop anti-donor specific cytotoxicity even after exposure to a supralethal dose (1050 R) of radiation and that the immunohematologic disturbances observed in shortterm F 1 to parent bone marrow chimeras (B6C3F 1 →C3Hf) were due to host-versus-graft reaction (HVGR) initiated by residual host T cells. The implication of these findings on the radiobiological nature of the residual T cells and the persistence of potentially anti-donor reactive T-cell clones in long-surviving allogeneic bone marrow chimeras was discussed

  6. Artificial muscle: the human chimera is the future.

    Science.gov (United States)

    Tozzi, P

    2011-12-14

    Severe heart failure and cerebral stroke are broadly associated with the impairment of muscular function that conventional treatments struggle to restore. New technologies enable the construction of "smart" materials that could be of great help in treating diseases where the main problem is muscle weakness. These materials "behave" similarly to biological systems, because the material directly converts energy, for example electrical energy into movement. The extension and contraction occur silently like in natural muscles. The real challenge is to transfer this amazing technology into devices that restore or replace the mechanical function of failing muscle. Cardiac assist devices based on artificial muscle technology could envelope a weak heart and temporarily improve its systolic function, or, if placed on top of the atrium, restore the atrial kick in chronic atrial fibrillation. Artificial sphincters could be used to treat urinary incontinence after prostatectomy or faecal incontinence associated with stomas. Artificial muscles can restore the ability of patients with facial paralysis due to stroke or nerve injury to blink. Smart materials could be used to construct an artificial oesophagus including peristaltic movement and lower oesophageal sphincter function to replace the diseased oesophagus thereby avoiding the need for laparotomy to mobilise stomach or intestine. In conclusion, in the near future, smart devices will integrate with the human body to fill functional gaps due to organ failure, and so create a human chimera.

  7. Present status of the Chimera-Isospin experiment

    Energy Technology Data Exchange (ETDEWEB)

    Politi, G.; Arena, N.; Cardella, G.; DeFilippo, E.; Lanzano, G.; Nigro, S.L.; Pagano, A.; Papa, M.; Pirrone, S.; Russotto, P. [Catania Univ., INFN (Italy); Alderighi, M.; Sechi, G.; Sperduto, M.L. [Milano Univ., INFN, CNR (Italy); Amorini, F.; Anzalone, A.; Baran, V.; Bonasera, A.; Cavallaro, S.L.; Colonna, M.; Di Toro, M.; LaGuidara, E.; Lanzalone, G.; IaconoManno, M.; Giustolisi, F.; Maiolino, C.; Porto, F.; Rizzo, F.; Trifiro, A.; Trimarchi, M. [Catania Univ., INFN, Lab. Nazionali del Sud (Italy); Auditore, L.; Barna, R.; DePasquale, D. [Messina Univ., INFN (Italy); Berceanu, I.; Petrovici, M.; Pop, A. [Inst. for Physics and Nuclear Engineering, Bucharest (Romania); Blicharska, J.; Grzeszczuk, A.; Kowalski, S.; Zipper, W. [Univ. of Silesia, Inst. of Physics, Katowice (Poland); Borderie, B.; LeNeindre, N.; Rivet, M.F. [Paris-11 Univ., IPN-IN2P3-CNRS, 91 - Orsay (France); Bougault, R. [Caen Univ., LPC-ISMRA (France); Briczycnski, J.; Gawlikowicz, W.; Majka, Z.; Planeta, R. [M. Smoluchowski Inst. of Physics, Jagellonian Univ., Cracow (Poland); Bruno, M.; D' Agostino, M.; Fuschini, E.; Geraci, E.; Vannini, G. [Bologna Univ., INFN (Italy); Chatterjee, M.B. [Saha Inst. of Nuclear Physics, NIS Div., Kolkata (India); Chbihi, A.; Wieleczko, J.P. [GANIL -CEA-IN2P3-CNRS, 14 - Caen (France); Cibor, J. [H.Niewodniczanski Inst. of Nuclear Physics, Cracow (Poland); Dayras, R. [CEA Saclay, Dept. d' Astrophysique, de Physique des Particules, de Physique Nucleaire et de l' Instrumentation Associee, SPhN, 91- Gif sur Yvette (France); Guazzoni, P.; Russo, S.; Sassi, M.; Zetta, L. [Milano Univ., INFN (Italy); Guinet, D. [Univ. Claude Bernard, IPN-IN2P3-CNRS, 69 - Lyon (France); Li, S.; Wu, H.; Xiao, Z. [Inst. of Modern Physics, Lanzhou (China); Nicolis, N.G. [Ioannina Univ., Dept. of Physics (Greece); Piasecki, E.; Swiderski, L.; Siwek-Wilczynska, K.; Skwira, I. [Warsaw Univ., Inst. for Experimental Physics (Poland); Rosato, E.; Vigilante, M.; Wilczynski, J.

    2003-07-01

    The CHIMERA detector was designed to significantly contribute to multifragmentation studies in the field of heavy ion collisions at intermediate energies. The device has been used at 'Laboratori Nazionali del Sud' (LNS) in Catania (Italy) to study different aspects of the relevant nuclear reaction mechanism, in two different campaigns: the first one in 2000, by using the forward part (1 - 30 degrees) of the device, and the second one in 2003, by using the 4{pi} geometry. The experimental results have confirmed the capability of the apparatus for good isotopic identification of light charged particles and light fragments (3

  8. Multidimensional simulations of core-collapse supernovae with CHIMERA

    Science.gov (United States)

    Lentz, Eric J.; Bruenn, S. W.; Yakunin, K.; Endeve, E.; Blondin, J. M.; Harris, J. A.; Hix, W. R.; Marronetti, P.; Messer, O. B.; Mezzacappa, A.

    2014-01-01

    Core-collapse supernovae are driven by a multidimensional neutrino radiation hydrodynamic (RHD) engine, and full simulation requires at least axisymmetric (2D) and ultimately symmetry-free 3D RHD simulation. We present recent and ongoing work with our multidimensional RHD supernova code CHIMERA to understand the nature of the core-collapse explosion mechanism and its consequences. Recently completed simulations of 12-25 solar mass progenitors(Woosley & Heger 2007) in well resolved (0.7 degrees in latitude) 2D simulations exhibit robust explosions meeting the observationally expected explosion energy. We examine the role of hydrodynamic instabilities (standing accretion shock instability, neutrino driven convection, etc.) on the explosion dynamics and the development of the explosion energy. Ongoing 3D and 2D simulations examine the role that simulation resolution and the removal of the imposed axisymmetry have in the triggering and development of an explosion from stellar core collapse. Companion posters will explore the gravitational wave signals (Yakunin et al.) and nucleosynthesis (Harris et al.) of our simulations.

  9. Total lymphoid irradiation

    International Nuclear Information System (INIS)

    Anon.

    1980-01-01

    An outline review notes recent work on total lymphoid irradiation (TLI) as a means of preparing patients for grafts and particularly for bone-marrow transplantation. T.L.I. has proved immunosuppressive in rats, mice, dogs, monkeys and baboons; when given before bone-marrow transplantation, engraftment took place without, or with delayed rejection or graft-versus-host disease. Work with mice has indicated that the thymus needs to be included within the irradiation field, since screening of the thymus reduced skin-graft survival from 50 to 18 days, though irradiation of the thymus alone has proved ineffective. A more lasting tolerance has been observed when T.L.I. is followed by an injection of donor bone marrow. 50% of mice treated in this way accepted allogenic skin grafts for more than 100 days, the animals proving to be stable chimeras with 50% of their peripheral blood lymphocytes being of donor origin. Experiments of a similar nature with dogs and baboons were not so successful. (U.K.)

  10. Effects of caffeine on X-irradiated synchronous, asynchronous and plateau phase mouse ascites cells: the importance of progression through the cell cycle for caffeine enhancement of killing

    International Nuclear Information System (INIS)

    Iliakis, G.; Nuesse, M.

    1983-01-01

    Caffeine potentiated the killing effect of X-rays on exponentially growing cells giving rise to exponential curves (D 0 =(0.8+-0.05)Gy) at 4mM and 14 hours treatment. Irradiated plateau phase cells were less sensitive. Exponentially growing cells also became less sensitive to the effects of caffeine when they were incubated in the conditioned medium of plateau phase cells(C-medium) in which cell growth was considerably inhibited. Low caffeine concentrations(2mM) enhanced X-ray induced killing of cells irradiated in G 1 -,G 1 /S- or S-phase, but more effectively G 2 -phase cells. High caffeine concentrations (6mM) enhanced killing of cells in all phases of the cell cycle. Incubation of synchronized populations in C-medium during treatment with caffeine (2mM and 6mM) resulted in less potentiation than in cells treated in fresh medium. The expression of X-ray induced potentially lethal damage caused by 6mM caffeine in cells irradiated in various phases resulted in an exponential survival curve with a mean lethal dose of (0.8+-0.05)Gy, but the time of caffeine treatment necessary to reach this curve was different for cells irradiated in different phases. PLD repair, measured as loss of sensitivity to 6mM caffeine (4 hours treatment) was of 1-2 hours duration. (author)

  11. Streptococcal cell wall-induced arthritis and adjuvant arthritis in F344----Lewis and in Lewis----F344 bone marrow chimeras

    International Nuclear Information System (INIS)

    van Bruggen, M.C.; van den Broek, M.F.; van den Berg, W.B.

    1991-01-01

    Streptococcal cell wall (SCW)-induced arthritis and adjuvant arthritis (AA) are rat models for chronic, erosive polyarthritis. Both models can be induced in susceptible Lewis rats, whereas F344 rats are resistant. In AA as well as in SCW arthritis, antigen-specific T lymphocytes have been demonstrated to be crucial for chronic disease. In this communication the authors describe their studies to probe the cellular mechanism responsible for the difference in susceptibility of Lewis and F344, using bone marrow chimeras. By transplanting bone marrow cells from F344 into lethally irradiated Lewis recipients, Lewis rats were rendered resistant to SCW arthritis induction. F344 rats reconstituted with Lewis bone marrow, i.e., Lewis----F344 chimeras, develop an arthritis upon SCW injection. For AA comparable results were obtained. These data suggest that both resistance and susceptibility to bacterium-induced chronic arthritis are mediated by hemopoietic/immune cells and that the recipiental environment does not influence the susceptibility to chronic joint inflammation

  12. Generation of an adenovirus-parvovirus chimera with enhanced oncolytic potential.

    Science.gov (United States)

    El-Andaloussi, Nazim; Bonifati, Serena; Kaufmann, Johanna K; Mailly, Laurent; Daeffler, Laurent; Deryckère, François; Nettelbeck, Dirk M; Rommelaere, Jean; Marchini, Antonio

    2012-10-01

    In this study, our goal was to generate a chimeric adenovirus-parvovirus (Ad-PV) vector that combines the high-titer and efficient gene transfer of adenovirus with the anticancer potential of rodent parvovirus. To this end, the entire oncolytic PV genome was inserted into a replication-defective E1- and E3-deleted Ad5 vector genome. As we found that parvoviral NS expression inhibited Ad-PV chimera production, we engineered the parvoviral P4 early promoter, which governs NS expression, by inserting into its sequence tetracycline operator elements. As a result of these modifications, P4-driven expression was blocked in the packaging T-REx-293 cells, which constitutively express the tetracycline repressor, allowing high-yield chimera production. The chimera effectively delivered the PV genome into cancer cells, from which fully infectious replication-competent parvovirus particles were generated. Remarkably, the Ad-PV chimera exerted stronger cytotoxic activities against various cancer cell lines, compared with the PV and Ad parental viruses, while being still innocuous to a panel of tested healthy primary human cells. This Ad-PV chimera represents a novel versatile anticancer agent which can be subjected to further genetic manipulations in order to reinforce its enhanced oncolytic capacity through arming with transgenes or retargeting into tumor cells.

  13. Chimera-like states in a neuronal network model of the cat brain

    Science.gov (United States)

    Santos, M. S.; Szezech, J. D.; Borges, F. S.; Iarosz, K. C.; Caldas, I. L.; Batista, A. M.; Viana, R. L.; Kurths, J.

    2017-08-01

    Neuronal systems have been modeled by complex networks in different description levels. Recently, it has been verified that networks can simultaneously exhibit one coherent and other incoherent domain, known as chimera states. In this work, we study the existence of chimera states in a network considering the connectivity matrix based on the cat cerebral cortex. The cerebral cortex of the cat can be separated in 65 cortical areas organised into the four cognitive regions: visual, auditory, somatosensory-motor and frontolimbic. We consider a network where the local dynamics is given by the Hindmarsh-Rose model. The Hindmarsh-Rose equations are a well known model of neuronal activity that has been considered to simulate membrane potential in neuron. Here, we analyse under which conditions chimera states are present, as well as the affects induced by intensity of coupling on them. We observe the existence of chimera states in that incoherent structure can be composed of desynchronised spikes or desynchronised bursts. Moreover, we find that chimera states with desynchronised bursts are more robust to neuronal noise than with desynchronised spikes.

  14. CAPRRESI: Chimera Assembly by Plasmid Recovery and Restriction Enzyme Site Insertion.

    Science.gov (United States)

    Santillán, Orlando; Ramírez-Romero, Miguel A; Dávila, Guillermo

    2017-06-25

    Here, we present chimera assembly by plasmid recovery and restriction enzyme site insertion (CAPRRESI). CAPRRESI benefits from many strengths of the original plasmid recovery method and introduces restriction enzyme digestion to ease DNA ligation reactions (required for chimera assembly). For this protocol, users clone wildtype genes into the same plasmid (pUC18 or pUC19). After the in silico selection of amino acid sequence regions where chimeras should be assembled, users obtain all the synonym DNA sequences that encode them. Ad hoc Perl scripts enable users to determine all synonym DNA sequences. After this step, another Perl script searches for restriction enzyme sites on all synonym DNA sequences. This in silico analysis is also performed using the ampicillin resistance gene (ampR) found on pUC18/19 plasmids. Users design oligonucleotides inside synonym regions to disrupt wildtype and ampR genes by PCR. After obtaining and purifying complementary DNA fragments, restriction enzyme digestion is accomplished. Chimera assembly is achieved by ligating appropriate complementary DNA fragments. pUC18/19 vectors are selected for CAPRRESI because they offer technical advantages, such as small size (2,686 base pairs), high copy number, advantageous sequencing reaction features, and commercial availability. The usage of restriction enzymes for chimera assembly eliminates the need for DNA polymerases yielding blunt-ended products. CAPRRESI is a fast and low-cost method for fusing protein-coding genes.

  15. Engineering human cytochrome P450 enzymes into catalytically self-sufficient chimeras using molecular Lego.

    Science.gov (United States)

    Dodhia, Vikash Rajnikant; Fantuzzi, Andrea; Gilardi, Gianfranco

    2006-10-01

    The membrane-bound human cytochrome P450s have essential roles in the metabolism of endogenous compounds and drugs. Presented here are the results on the construction and characterization of three fusion proteins containing the N-terminally modified human cytochrome P450s CYP2C9, CY2C19 and CYP3A4 fused to the soluble NADPH-dependent oxidoreductase domain of CYP102A1 from Bacillus megaterium. The constructs, CYP2C9/BMR, CYP2C19/BMR and CYP3A4/BMR are well expressed in Escherichia coli as holo proteins. The chimeras can be purified in the absence of detergent and the purified enzymes are both active and correctly folded in the absence of detergent, as demonstrated by circular dichroism and functional studies. Additionally, in comparison with the parent P450 enzyme, these chimeras have greatly improved solubility properties. The chimeras are catalytically self-sufficient and present turnover rates similar to those reported for the native enzymes in reconstituted systems, unlike previously reported mammalian cytochrome P450 fusion proteins. Furthermore the specific activities of these chimeras are not dependent on the enzyme concentration present in the reaction buffer and they do not require the addition of accessory proteins, detergents or phospholipids to be fully active. The solubility, catalytic self-sufficiency and wild-type like activities of these chimeras would greatly simplify the studies of cytochrome P450 mediated drug metabolism in solution.

  16. Restoring efficiency of hemopoietic cell transplantation in a mouse lethally irradiated by a total exposure to X rays; L'efficacite restauratrice de la greffe de cellules hemopoietiques chez la souris letalement irradiee par une exposition totale aux rayons X

    Energy Technology Data Exchange (ETDEWEB)

    Doria, Gino

    1959-10-15

    This research thesis reports the study of possibility of treatments (or restoration) of a mouse which has been submitted to a lethal dose of X rays. More particularly, the author compared the restoring efficiency of bone marrow and fetal liver injected in a mouse which had been lethally irradiated by a total exposure to X rays. He also studied the functional status of the hemopoietic graft, and the emergence of the secondary disease in mice which had been as well lethally irradiated and then restored by injection of bone marrow and fetal liver. The author then addressed the influence of the induction of immune tolerance of the host with respect to the donor on the survival of a mouse lethally irradiated and restored by homologue bone marrow [French] Des resultats des recherches que nous avons conduites permettent, dans les limites de nos conditions experimentales, d'eclaircir certains aspects du probleme de la restauration des animaux irradies par la greffe de cellules hemopoietiques. On peut admettre que la moelle osseuse de 30 jours est 2 fois plus efficace que le foie foetal de 16 jours, pour ce qui concerne la survie 30 jours; ceci aussi bien en cas de restauration isologue que homologue. En outre, le foie foetal de 16 jours permet une survie d'environ 50 pc plus elevee que les foies foetaux de 13 ou 19 jours; ceci en cas de restauration isologue. On a aussi montre que les degres de capacite restauratrice des differents tissus hemopoietiques dependent du nombre de cellules souches, progenitrices des granulocytes polynucleaires. Nous avons mis en evidence, en cas de restauration par la moelle osseuse homologue, que la presence d'un greffon hemopoietique fonctionnel est necessaire et suffisante pour l'apparition de la maladie secondaire et que celle-ci est une cause suffisante et non necessaire de la mortalite tardive. La constatation experimentale que la viabilite du greffon est une cause suffisante et non necessaire de la mortalite tardive en est la preuve

  17. Depletion of Primordial Germ Cells (PGCs) by X-irradiation to Extraembryonic Region of Chicken Embryos and Expression of Xenotransplanted Quail PGCs

    OpenAIRE

    Atsumi, Yusuke; Yazawa, Shigenobu; Usui, Fumitake; Nakamura, Yoshiaki; Yamamoto, Yasuhiro; Tagami, Takahiro; Hiramatsu, Kohzy; Kagami, Hiroshi; Ono, Tamao

    2009-01-01

    The generation of germline chimeras by the transfer of primordial germ cells (PGCs) requires incorporation of the PGCs of the donor into the gonadal tissue of the recipient embryo. We investigated the utility of soft x-irradiation with application of a lead (12-3 x 0.25 mm, similar to 0.1 g) shield to the embryo proper for the production of chicken-quail germline chimeras. Chicken embryos shielded during irradiation for 120 s (similar to 7.2 Gy) at stages 13 to 17 showed a hatchability of 35%...

  18. The radioprotector WR-2721 reduces neutron-induced mutations at the hypoxanthine-guanine phosphoribosyl transferase locus in mouse splenocytes when administered prior to or following irradiation

    International Nuclear Information System (INIS)

    Grdina, D.J.; Basic, I.

    1992-01-01

    An in vitro T-lymphocyte cloning technique has been applied to study the effects of JANUS fission-spectrum neutron irradiation and the radioprotector S-2-(3-aminopropylamino) ethylphosphorothioic acid (WR-2721) on the subsequent development of somatic mutations at the hypoxanthine-guanine phosphoribosyl transferase (hprt) locus in hybrid B6CF1 male mice. In control studies performed to establish an in vitro cloning technique, the mutant frequencies of splenic T-lymphocytes, as a result of exposure to a 100 cGy dose of neutrons, increased with time from a control level of 9 x 10 -7 to a maximum value of 1.7 x 10 -5 at 56 days following irradiation. Between 56 and 150 days after irradiation, mutant frequencies were observed to plateau and remain stable. All subsequent determinations were performed at 56 days following the experimental treatment of animals. WR-2721 at a dose of 400 mg/kg was effective in protecting against the induction of hprt mutants (i.e. a mutant frequency reduction factor, MFRF) following the largest dose of neutrons used (i.e. 150 cGy). The antimutagenic effectiveness of WR-2721 administered 30 min prior to irradiation was unaffected, even when the dose was reduced to 200 mg/kg. These findings confirm our earlier report using the radioprotector N-(2-mercaptoethyl)-1,2-diaminopropane (WR-1065) under in vitro conditions, and demonstrate that these agents can be used as effective antimutagens even when they are administered up to 3 h following radiation exposure. (Author)

  19. The Chimera II Real-Time Operating System for advanced sensor-based control applications

    Science.gov (United States)

    Stewart, David B.; Schmitz, Donald E.; Khosla, Pradeep K.

    1992-01-01

    Attention is given to the Chimera II Real-Time Operating System, which has been developed for advanced sensor-based control applications. The Chimera II provides a high-performance real-time kernel and a variety of IPC features. The hardware platform required to run Chimera II consists of commercially available hardware, and allows custom hardware to be easily integrated. The design allows it to be used with almost any type of VMEbus-based processors and devices. It allows radially differing hardware to be programmed using a common system, thus providing a first and necessary step towards the standardization of reconfigurable systems that results in a reduction of development time and cost.

  20. Chimera and phase-cluster states in populations of coupled chemical oscillators

    Science.gov (United States)

    Tinsley, Mark R.; Nkomo, Simbarashe; Showalter, Kenneth

    2012-09-01

    Populations of coupled oscillators may exhibit two coexisting subpopulations, one with synchronized oscillations and the other with unsynchronized oscillations, even though all of the oscillators are coupled to each other in an equivalent manner. This phenomenon, discovered about ten years ago in theoretical studies, was then further characterized and named the chimera state after the Greek mythological creature made up of different animals. The highly counterintuitive coexistence of coherent and incoherent oscillations in populations of identical oscillators, each with an equivalent coupling structure, inspired great interest and a flurry of theoretical activity. Here we report on experimental studies of chimera states and their relation to other synchronization states in populations of coupled chemical oscillators. Our experiments with coupled Belousov-Zhabotinsky oscillators and corresponding simulations reveal chimera behaviour that differs significantly from the behaviour found in theoretical studies of phase-oscillator models.

  1. Effects of 60Co gamma irradiation on Eimeria falciformis (Eimer 1870) Schneider 1875, a protozoan parasite of the mouse, Mus musculus L

    International Nuclear Information System (INIS)

    Wright, A.C.

    1976-01-01

    Oocysts of an E. falciformis strain first isolated in Wuppertal, Germany were exposed to cobalt-60 gamma radiation under different conditions of oocyst age and development. In order to construct survival curves for oocysts irradiated in the unsporulated state, normalized percent sporulation was plotted as a function of radiation dose. Oocysts irradiated in the sporulated state never caused infection after receiving doses of 50 krads or more. Rarely, oocysts which had received 40 krads produced infection and completed their life cycle in susceptible hosts, but usually the doses beyond which infection did not occur ranged from 30 to 35 krads. Immunity was shown best by hosts which had received unirradiated oocysts in vaccinations prior to challenge. When irradiated sporulated oocysts were used in attempts to immunize susceptible hosts against coccidiosis, the most positive results were obtained from oocysts which had been exposed to 20 krads. Animals receiving vaccinations of oocysts exposed to 20 krads always survived the minimal infections caused by vaccination and also exhibited good immunity to challenge

  2. Follow-up study on histogenesis of microcephaly associated with ectopic gray matter induced by prenatal γ-irradiation in the mouse

    International Nuclear Information System (INIS)

    Sun, Xue-Zhi; Inouye, Monoru; Takagishi, Yoshiko

    1996-01-01

    Brain malformation with ectopic gray matter was visualized with magnetic resonance imaging in small-sized heads of prenatally exposed atomic bomb survivors. The identical brain malformation was reproduced in mice and its histogenesis was studied in the present experiment. Pregnant mice were exposed to 60 Co γ-irradiation at a single dose of 1.5 Gy on embryonic day 13 (E13), and then injected intraperitoneally with 30 mg/kg BrdU on E15. The extensive dead cells appeared throughout the brain mantle at 6 hours (h) after exposure. On E16 cell aggregations formed rosettes. On E18 a high proportion of BrdU-labeled cells reached the superficial layers of the cortical plate with the remaining cells located in the ectopic neuronal masses. The quantitative study showed that labeled cells in layers II to III were fewer and those in layers IV to VI more numerous in the prenatally irradiated adult mice than in controls. The anti-GFAP immunostaining revealed that the glial fibers in the irradiated mice were preserved, but disorganized. These findings suggested that the majority of migrating neurons were able to arrive at their normal layers, but some neurons remained due to the interrupted migratory pathway and eventually formed ectopic neuronal masses beneath the subcortical white matter. 60 refs., 5 figs., 1 tab

  3. Chimera states in a multilayer network of coupled and uncoupled neurons

    Science.gov (United States)

    Majhi, Soumen; Perc, Matjaž; Ghosh, Dibakar

    2017-07-01

    We study the emergence of chimera states in a multilayer neuronal network, where one layer is composed of coupled and the other layer of uncoupled neurons. Through the multilayer structure, the layer with coupled neurons acts as the medium by means of which neurons in the uncoupled layer share information in spite of the absence of physical connections among them. Neurons in the coupled layer are connected with electrical synapses, while across the two layers, neurons are connected through chemical synapses. In both layers, the dynamics of each neuron is described by the Hindmarsh-Rose square wave bursting dynamics. We show that the presence of two different types of connecting synapses within and between the two layers, together with the multilayer network structure, plays a key role in the emergence of between-layer synchronous chimera states and patterns of synchronous clusters. In particular, we find that these chimera states can emerge in the coupled layer regardless of the range of electrical synapses. Even in all-to-all and nearest-neighbor coupling within the coupled layer, we observe qualitatively identical between-layer chimera states. Moreover, we show that the role of information transmission delay between the two layers must not be neglected, and we obtain precise parameter bounds at which chimera states can be observed. The expansion of the chimera region and annihilation of cluster and fully coherent states in the parameter plane for increasing values of inter-layer chemical synaptic time delay are illustrated using effective range measurements. These results are discussed in the light of neuronal evolution, where the coexistence of coherent and incoherent dynamics during the developmental stage is particularly likely.

  4. Application of Chimera Grid Scheme to Combustor Flowfields at all Speeds

    Science.gov (United States)

    Yungster, Shaye; Chen, Kuo-Huey

    1997-01-01

    A CFD method for solving combustor flowfields at all speeds on complex configurations is presented. The approach is based on the ALLSPD-3D code which uses the compressible formulation of the flow equations including real gas effects, nonequilibrium chemistry and spray combustion. To facilitate the analysis of complex geometries, the chimera grid method is utilized. To the best of our knowledge, this is the first application of the chimera scheme to reacting flows. In order to evaluate the effectiveness of this numerical approach, several benchmark calculations of subsonic flows are presented. These include steady and unsteady flows, and bluff-body stabilized spray and premixed combustion flames.

  5. Polariton Chimeras: Bose-Einstein Condensates with Intrinsic Chaoticity and Spontaneous Long-Range Ordering

    Science.gov (United States)

    Gavrilov, S. S.

    2018-01-01

    The system of cavity polaritons driven by a plane electromagnetic wave is found to undergo the spontaneous breaking of spatial symmetry, which results in a lifted phase locking with respect to the driving field and, consequently, in the possibility of internal ordering. In particular, periodic spin and intensity patterns arise in polariton wires; they exhibit strong long-range order and can serve as media for signal transmission. Such patterns have the properties of dynamical chimeras: they are formed spontaneously in perfectly homogeneous media and can be partially chaotic. The reported new mechanism of chimera formation requires neither time-delayed feedback loops nor nonlocal interactions.

  6. Induction of chlorophyll chimeras and chlorophyll mutations in mungbean (Vigna radiata) cv. T44

    International Nuclear Information System (INIS)

    Singh, V.P.; Yadav, R.D.S.

    1993-01-01

    Uniform and healthy seeds of mungbean (Vigna radiata) cv. T44 were exposed to varying doses of gamma rays, ethyl methane sulphonate (EMS) and combination treatment of gamma rays with EMS. The data were recorded for seed germination, plant survival, frequency and spectrum of chlorophyll chimeras in M 1 and chlorophyll mutations in M 2 generation. Among all, the combination treatments were found most effective for inducing chlorophyll chimeras and chlorophyll mutations than the gamma rays or EMS alone. Of the mutants under reference, the albino, xantha and chlorina showed monogenic recessive while viridis exhibited digenic recessive inheritance. (author). 8 refs., 2 tabs

  7. RNA Chimeras as a Gene Signature of Breast Cancer

    Science.gov (United States)

    2014-06-01

    in the human [26,27] and another one in the mouse [28]. Human mtDNA does not contain introns and thus Figure 4. Cis- or trans- spiced mtRNA in ESTs...Therefore, the exact nt numbers and locations might slightly differ from different publications. RT-PCR, T-A cloning and DNA sequencing We cultured HEK293

  8. 2.45-GHz microwave irradiation adversely affects reproductive function in male mouse, Mus musculus by inducing oxidative and nitrosative stress.

    Science.gov (United States)

    Shahin, S; Mishra, V; Singh, S P; Chaturvedi, C M

    2014-05-01

    Electromagnetic radiations are reported to produce long-term and short-term biological effects, which are of great concern to human health due to increasing use of devices emitting EMR especially microwave (MW) radiation in our daily life. In view of the unavoidable use of MW emitting devices (microwaves oven, mobile phones, Wi-Fi, etc.) and their harmful effects on biological system, it was thought worthwhile to investigate the long-term effects of low-level MW irradiation on the reproductive function of male Swiss strain mice and its mechanism of action. Twelve-week-old mice were exposed to non-thermal low-level 2.45-GHz MW radiation (CW for 2 h/day for 30 days, power density = 0.029812 mW/cm(2) and SAR = 0.018 W/Kg). Sperm count and sperm viability test were done as well as vital organs were processed to study different stress parameters. Plasma was used for testosterone and testis for 3β HSD assay. Immunohistochemistry of 3β HSD and nitric oxide synthase (i-NOS) was also performed in testis. We observed that MW irradiation induced a significant decrease in sperm count and sperm viability along with the decrease in seminiferous tubule diameter and degeneration of seminiferous tubules. Reduction in testicular 3β HSD activity and plasma testosterone levels was also noted in the exposed group of mice. Increased expression of testicular i-NOS was observed in the MW-irradiated group of mice. Further, these adverse reproductive effects suggest that chronic exposure to nonionizing MW radiation may lead to infertility via free radical species-mediated pathway.

  9. Evidence for mouse Th1- and Th2-like helper T cells in vivo. Selective reduction of Th1-like cells after total lymphoid irradiation

    International Nuclear Information System (INIS)

    Bass, H.; Mosmann, T.; Strober, S.

    1989-01-01

    Purified CD4+ BALB/c spleen T cells obtained 4-6 wk after total lymphoid irradiation (TLI) helped normal syngeneic B cells to produce a vigorous antibody response to TNP keyhole limpet hemocyanin in adoptive cell transfer experiments. However, the same cells failed to transfer delayed-type hypersensitivity to the adoptive hosts as measured by a foot pad swelling assay. In addition, purified CD4+ cells from TLI-treated mice were unable to induce graft vs. host disease in lethally irradiated allogeneic C57BL/Ka recipient mice. In response to mitogen stimulation, unfractionated spleen cells obtained from TLI mice secreted normal levels of IL-4 and IL-5, but markedly reduced levels of IL-2 and INF-gamma. A total of 229 CD4+ clones from spleen cells of both normal and TLI-treated mice were established, and the cytokine secretion pattern from each clone was analyzed. The results demonstrate that the ratio of Th1- and Th2-like clones in the spleens of normal BALB/c mice is 1:0.6, whereas the ratio in TLI mice is approximately 1:7. These results suggest that Th2-like cells recover rapidly (at approximately 4-6 wk) after TLI treatment and account for the early return of antibody helper activity and secretion of IL-4 and IL-5, but Th1-like cells recover more slowly (in approximately 3 mo) after irradiation, and this accounts for the deficit in cell-mediated immunity and the reduced amount of IL-2 and IFN-gamma secretion

  10. Use of dexpanthenol and aloe vera to influence the irradiation response of the oral mucous membrane (mouse); Beeinflussung der Strahlenreaktion der Mundschleimhaut (Maus) durch Dexpanthenol {+-} Aloe vera

    Energy Technology Data Exchange (ETDEWEB)

    Schlichting, S. [Klinik und Poliklinik fuer Strahlentherapie und Radioonkologie, Dresden Univ. (Germany); Spekl, K.; Doerr, W. [Klinik und Poliklinik fuer Strahlentherapie und Radioonkologie, Dresden Univ. (Germany)]|[Experimentelles Zentrum, Medizinische Fakultaet Carl Gustav Carus, Dresden Univ. (Germany)

    2004-07-01

    In summarising the outcome of the present study it can be said spraying the agent on the oral mucous membrane once a day had an effect on the incidence of mucous membrane ulceration in the case of both placebo and dexpanthenol treatment. However, there was no significant difference between placebo and dexpanthenol treatment, the only finding being a slight prolongation of latency time through aloe vera. These experimental findings give good reason to critically reconsider the clinical use of dexpanthenol as a supportive treatment for the prevention of radiogenic mucositis enoralis following irradiation of tumours in the head and neck region. However thorough oral lavage is an effective means of moderating the irradiation response of the oral mucous membrane. [German] Zusammenfassend ist festzustellen, dass in den vorliegenden Versuchen mit einmal taeglichem Aufspruehen des Praeparates auf die Mundschleimhaut sowohl die Placebo - wie auch die Dexpanthenol-Behandlung die Inzidenz von Schleimhautulzerationen modifiziert hat; zwischen Placebo- und Dexpanthenol-Behandlung ergab sich jedoch kein signifikanter Unterschied. Lediglich eine geringe Verlaengerung der Latenzzeit durch Aloe vera war zu beobachten. Auf der Basis dieser experimentellen Ergebnisse muss der klinische Einsatz von Dexpanthenol im Rahmen der Supportivtherapie zur Prophylaxe der radiogenen Mucositis enoralis bei der Bestrahlung von Kopf-Hals-Tumoren kritisch ueberdacht werden. Regelmaessige, intensive Mundspuelungen sind jedoch ein probates Mittel zur Verminderung der Strahlenreaktion der Mundschleimhaut. (orig.)

  11. Induction and repair of lethal and oncogenic lesions and their relationship to cytogenetic changes in UV-irradiated mouse 10T1/2 cells

    International Nuclear Information System (INIS)

    Chan, G.L.; Nagasawa, H.; Little, J.B.

    1979-01-01

    While bacterial system is valuable for the pragmatic purpose of screening potential environmental carcinogens, the fundamental difference between prokaryotes and mammalian cells warrant caution against the use of bacterial mutagenic mechanisms to explain the oncogenic process in mammalian cells. The 10 T1/2 cells exposed to UV light in the plateau phase and subcultured immediately to low density to assay for clonogenic survival were extremely resistant to the cytotoxic effect of UV light. Purely physical considerations such as the increased thickness of plateau phase cells and the increased cytoplasmic shielding of UV light from the nuclei were insufficient to account for this unusual resistance. The effect of caffeine on the repair processes in UV-irradiated mammalian cells appears to be exerted during the first DNA synthetic phase after the UV exposure. The daughter DNA synthesized on a UV-irradiated template is of reduced molecular weight. 10 T1/2 cells were exposed in the log phase of growth to UV light, and then they were cultured for the next 48 hours in the complete growth medium containing the specific concentration of caffeine. Parallel experiments were performed, in which cells were exposed for 48 hours to caffeine only with no prior exposure to UV light. It was found that caffeine did not potentiate the transformation by UV light. Caffeine alone induced sister chromatid exchange (SCE), whereas the caffeine given after UV light had no effect. The class of UV-induced lesions which induce SCE also leads to malignant transformation. (Yamashita, S.)

  12. Intrathymic T cell differentiation in radiation bone marrow chimeras and its role in T cell emigration to the spleen. An immunohistochemical study

    International Nuclear Information System (INIS)

    Hirokawa, K.; Sado, T.; Kubo, S.; Kamisaku, H.; Hitomi, K.; Utsuyama, M.

    1985-01-01

    Immunohistochemical studies were made on the regeneration of T cells of host- and donor-type in the thymus and spleen of radiation bone marrow chimeras by using B10- and B10.BR-Thy-1 congenic mice. In Thy-1 congenic chimeras, thymocytes of donor bone marrow origin, were first recognized at day 7, when the thymus involuted to the smallest size after the irradiation. The thymocytes of donor-type then proliferated exponentially, showing a slightly faster rate when higher doses of bone marrow cells were used for reconstitution, reaching a level of 100 million by day 17 and completely replacing the cortical thymocytes of host origin by day 21. The replacement of medullary thymocytes from host- to donor-type occurred gradually between days 21 and 35, after the replacement in the cortex was completed. In the spleen, about 1 million survived cells were recovered at day 3 after the irradiation, and approximately 60% of them were shown to be host-type T cells that were observed in the white pulp areas. The host-type T cells in the spleen increased gradually after day 10, due to the influx of host-type T cells from the regenerating thymus. Thus a pronounced increase of T cells of host-type was immunohistochemically observed in the splenic white pulp between days 21 and 28, when thymocytes of host-type were present mainly in the thymic medulla. These host-type T cells were shown to persist in the spleen for a long time, as long as 420 days after the treatment. Phenotypically, they were predominantly Lyt-1+2+ when examined at day 28, but 5 mo later, they were about 50% Lyt-1+2+ and 50% Lyt-1+2-

  13. Diversity of chimera-like patterns from a model of 2D arrays of neurons with nonlocal coupling

    Science.gov (United States)

    Tian, Chang-Hai; Zhang, Xi-Yun; Wang, Zhen-Hua; Liu, Zong-Hua

    2017-06-01

    Chimera states have been studied in 1D arrays, and a variety of different chimera states have been found using different models. Research has recently been extended to 2D arrays but only to phase models of them. Here, we extend it to a nonphase model of 2D arrays of neurons and focus on the influence of nonlocal coupling. Using extensive numerical simulations, we find, surprisingly, that this system can show most types of previously observed chimera states, in contrast to previous models, where only one or a few types of chimera states can be observed in each model. We also find that this model can show some special chimera-like patterns such as gridding and multicolumn patterns, which were previously observed only in phase models. Further, we present an effective approach, i.e., removing some of the coupling links, to generate heterogeneous coupling, which results in diverse chimera-like patterns and even induces transformations from one chimera-like pattern to another.

  14. "American Chimera: The Ever-Present Domination of Whiteness, Patriarchy, and Capitalism…A Parable"

    Science.gov (United States)

    Montoya, Roberto; Matias, Cheryl E.; Nishi, Naomi W. M.; Sarcedo, Geneva L.

    2016-01-01

    In Greek mythology, the Chimera is a fire-breathing monster with three heads: one of a lion, one of a horned goat, and one of a powerful dragon. Of similar construction is the presence of three structures in US society, whiteness, patriarchy, and capitalism, which are overwhelmingly represented, valued, and espoused when examining areas of…

  15. Analysis of the hormone-binding domain of steroid receptors using chimeras generated by homologous recombination

    International Nuclear Information System (INIS)

    Martinez, Elisabeth D.; Pattabiraman, Nagarajan; Danielsen, Mark

    2005-01-01

    The glucocorticoid receptor and the mineralocorticoid receptor are members of the steroid receptor family that exhibit ligand cross-reactivity. Specificity of steroid receptor action is investigated in the present work by the construction and characterization of chimeras between the glucocorticoid receptor and the mineralocorticoid receptor. We used an innovative approach to make novel steroid receptor proteins in vivo that in general, contrary to our expectations, show increased ligand specificity compared to the parental receptors. We describe a receptor that is specific for the potent synthetic glucocorticoid triamcinolone acetonide and does not bind aldosterone. A further set of chimeras has an increased ability to discriminate between ligands, responding potently to mineralocorticoids and only very weakly to synthetic glucocorticoids. A chimera with the fusion site in the hinge highlights the importance of the region between the DNA-binding and the hormone-binding domains since, unlike both the glucocorticoid and mineralocorticoid receptors, it only responds to mineralocorticoids. One chimera has reduced specificity in that it acts as a general corticoid receptor, responding to glucocorticoids and mineralocorticoids with similar potency and efficacy. Our data suggest that regions of the glucocorticoid and mineralocorticoid receptor hormone-binding domains are functionally non-reciprocal. We present transcriptional, hormone-binding, and structure-modeling evidence that suggests that receptor-specific interactions within and across domains mediate aspects of specificity in transcriptional responses to steroids

  16. Studies on the mechanism of the self restriction of T cell responses in radiation chimeras

    International Nuclear Information System (INIS)

    Fink, P.J.; Bevan, M.J.

    1981-01-01

    Recent experiments with murine radiation chimeras have shown that F 1 T cells that mature in an H-2 homozygous thymus, as is the case in [F 1 → Parent 1] chimeras, are restricted to recognizing foreign antigen in the context of Parent 1 H-2 antigens. Conflicting results on the stringency of self H-2 restriction of T cells from normal mice have suggested that the thymic restriction in chimeras may be due to active suppression of parent 2-restricted T cell clones. We have therefore conducted 3 sets of experiments to test for suppression of maturing T cells that could mediate thymic tutoring of H-2-restriction specificity in chimeras. In 2 sets of experiments, we found no evidence that suppressor cells could be exported from 1 thymus and act either intrathymically on thymocytes in a 2nd thymus or extrathymically on recent thymic emigrants. We believe current data support a role for the thymus in positive as well as negative selection of maturing thymocytes on the basis of self recognition, in the absence of any suppression. Our results do not support the concept that suppression is responsible for